A suspension assembly includes a load beam terminating in a hinge, a gimbal assembly mounted to the load beam, and a base plate connected to the hinge and including an opening. A PZT actuator is disposed in the opening and includes first and second opposing ends. The PZT actuator includes active and inactive regions both extending between the first and second opposing ends, PZT material disposed in both the active and inactive regions, and first and second electrodes configured to cause active expansion and contraction of the PZT material in the active region in response to voltage differentials applied to the first and second electrodes, and configured to not cause active expansion and contraction of the PZT material in the inactive region in response to voltage differentials applied to the first and second electrodes of the PZT actuator.
Examples of a head stack assembly arm are described herein. The head stack assembly arm includes a load beam in an upper nesting configuration including a lift tab with an inner edge. The head stack assembly arm includes a load beam in a lower nesting configuration including a lift tab with an inner edge, the inner edge of the load beam in the lower nesting configuration is a different size from the inner edge of the load beam in the upper nesting configuration.
A suspension assembly includes a load beam terminating in a hinge, a gimbal assembly mounted to the load beam, and a base plate connected to the hinge and including an opening. A PZT actuator is disposed in the opening and includes first and second opposing ends. The PZT actuator includes active and inactive regions both extending between the first and second opposing ends, PZT material disposed in both the active and inactive regions, and first and second electrodes configured to cause active expansion and contraction of the PZT material in the active region in response to voltage differentials applied to the first and second electrodes, and configured to not cause active expansion and contraction of the PZT material in the inactive region in response to voltage differentials applied to the first and second electrodes of the PZT actuator.
G11B 5/56 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of adjusting the position of the head relative to the record carrier, e.g. manual adjustment for azimuth correction or track centering
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
A head gimbal assembly includes a gimbal having a base portion and a tongue that are joined together by a neck portion, a circuit mounted on the gimbal, a slider mounted on the tongue and electrically connected to the circuit, a first PZT actuator having a proximal end mounted on a first bonding site of the circuit and a distal end mounted on a second bonding site of the circuit, and a second PZT actuator having a proximal end mounted on a third bonding site of the circuit and a distal end mounted on a fourth bonding site of the circuit. The first and third bonding sites do not overlap with and are not directly supported by the base portion. The second and fourth bonding sites overlap with and are directly supported by the tongue.
H10N 30/063 - Forming interconnections, e.g. connection electrodes of multilayered piezoelectric or electrostrictive parts
G11B 21/10 - Track finding or aligning by moving the head
H10N 30/057 - Manufacture of multilayered piezoelectric or electrostrictive devices, or parts thereof, e.g. by stacking piezoelectric bodies and electrodes by stacking bulk piezoelectric or electrostrictive bodies and electrodes
H10N 30/50 - Piezoelectric or electrostrictive devices having a stacked or multilayer structure
G11B 5/56 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of adjusting the position of the head relative to the record carrier, e.g. manual adjustment for azimuth correction or track centering
G11B 21/18 - Supporting the headsSupporting the sockets for plug-in heads while the head is moving
G11B 21/20 - Supporting the headsSupporting the sockets for plug-in heads while the head is in operative position but stationary or permitting minor movements to follow irregularities in surface of record carrier
H02N 2/02 - Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuatorsLinear positioners
A head gimbal assembly includes a gimbal having a base portion and a tongue that are joined together by a neck portion, a circuit mounted on the gimbal, a slider mounted on the tongue and electrically connected to the circuit, a first PZT actuator having a proximal end mounted on a first bonding site of the circuit and a distal end mounted on a second bonding site of the circuit, and a second PZT actuator having a proximal end mounted on a third bonding site of the circuit and a distal end mounted on a fourth bonding site of the circuit. The first and third bonding sites do not overlap with and are not directly supported by the base portion. The second and fourth bonding sites overlap with and are directly supported by the tongue.
A dielectric layer configured to overlay a spring metal layer in a suspension assembly is described. The dielectric layer includes a tongue portion including a proximate end and a distal end, trace portions extending from the tongue portion, and an aperture aligned with the void and defined by the tongue portion. The aperture includes an elongated opening with opposing ends partially aligning with the central opening of the void. The aperture further includes slits extending from the opposing ends of the elongated opening and at least partially aligned with slits of the void in the spring metal layer.
A flexure is described herein. The flexure includes a slider tongue with a proximal end and a distal end. The sliding tongue including a leading edge at the proximal end prone to contact an undersurface of a load beam attached to the flexure. The flexure also includes a magnetic read/write head slider attached to the slider tongue at the distal end, at least one PZT microactuator affixed to the slider tongue, between the proximal end and the distal end, and at least one dampening device at the leading edge of the slider tongue configured to reduce an impulse during a non-operational shock event and reduce stress on the at least one PZT microactuator.
A gimbal having a base portion and a tongue joined together by a neck portion. The base portion includes a first proximal edge facing away from the tongue. A circuit is mounted on the gimbal and includes a portion mounted to the base portion having a circuit extension region that extends beyond the first proximal edge. The circuit extension region includes a second proximal edge facing away from the tongue. A slider may be mounted on the tongue and electrically connected to the circuit. First and second PZT actuators are mounted to the head gimbal assembly and electrically connected to the circuit. The circuit extension region has a circuit extension region width W of at least 0.1 mm as measured in a direction extending away from the tongue relative to a furthest extending portion of the first proximal edge and a furthest extending portion of the second proximal edge.
A trace gimbal is described. The trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger. The rear outrigger includes a distal rear outrigger and a proximal rear outrigger. The trace gimbal also includes a middle strut extending from the distal rear outrigger and adjoining the proximal front outrigger to the rear outrigger. The middle strut extends from a slider tongue adjoining the outer gimbal struts to the slider tongue.
A suspension assembly includes a load beam, a base plate connected to the load beam, and a single actuator disposed in an opening of the base plate. The single actuator is formed of a crystal material that expands along a first axis and contracts along a second orthogonal axis, and expands along the second axis and contracts along the first axis in response to respective first and second bias voltages. The single actuator is configured to flex the base plate when expanding along the first axis to rotate the load beam in a first rotational direction about a center of rotation located along the load beam, and flex the base plate when expanding along the second axis to rotate the load beam in a second, opposite rotational direction about the center of rotation.
A gimbal assembly includes a frame having base, tip and mount portions, and a crossbar joined to the tip portion by a neck region. Portions of the crossbar and neck region define transition edge regions each extending from a point of minimum width D of the neck region to where the edge of the crossbar becomes substantially straight. Each of the transition edge regions includes a transition length a and a transition width b. The frame comprises an area of interest that includes the neck region and a portion of the crossbar that has a length of 0.6 mm and is centered to the neck region, and has a total area size A, a centroid C and a centroid distance H between the centroid C and a far side of the neck region. The crossbar and neck region have geometries that satisfy a design metric that is less than 0.05.
A suspension assembly includes a baseplate having an upper surface and a lower surface opposite the upper surface, a load beam mounted to the baseplate, a cylindrical hub extending from the upper surface, wherein the cylindrical hub comprises an inner surface that defines a swage hole extending through the baseplate, and a plurality of dimples protruding from the upper surface of the baseplate, wherein each of the dimples includes a rounded side protruding from the upper surface of the baseplate and terminating in an apex. The apexes of the dimples define a contact plane for engaging with the lower surface of the actuator arm swaged to the cylindrical hub.
A suspension assembly includes a baseplate having an upper surface and a lower surface opposite the upper surface, a load beam mounted to the baseplate, a cylindrical hub extending from the upper surface, wherein the cylindrical hub comprises an inner surface that defines a swage hole extending through the baseplate, and a plurality of dimples protruding from the upper surface of the baseplate, wherein each of the dimples includes a rounded side protruding from the upper surface of the baseplate and terminating in an apex. The apexes of the dimples define a contact plane for engaging with the lower surface of the actuator arm swaged to the cylindrical hub.
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
15.
LOAD BEAM LIMITER TABS FOR HAMR HEAD SLIDER PROTECTION
Examples of a load beam are provided. The load beam includes a base portion with an opening at a distal end. The opening is configured to receive a heat assisted magnetic recording (HAMR) head slider extending therethrough. The load beam also includes at least one load beam tab such that the load beam tab is further away from the base portion and a top surface of the HAMR head slider.
Examples of a load beam are provided. The load beam includes a base portion with an opening at a distal end. The opening is configured to receive a heat assisted magnetic recording (HAMR) head slider extending therethrough. The load beam also includes at least one load beam tab such that the load beam tab is further away from the base portion and a top surface of the HAMR head slider.
A trace gimbal is described herein. In some embodiments, the trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger, and the rear outrigger includes a distal rear outrigger and a proximal rear outrigger. The trace gimbal further includes a middle strut extending in a width direction of the trace gimbal and adjoining the proximal front outrigger to the rear outrigger, and an inner strut connecting the middle strut to a slider tongue. The inner strut and the middle strut adjoin the outer gimbal struts to the slider tongue.
The present disclosure relates generally to suspension assemblies for supporting read/write heads adjacent rotating disks in disk drives and more particularly, to a baseplate with an etched hub geometry. Examples of a baseplate of a suspension assembly are provided. The baseplate includes a hub region and a flange extending from the hub region. The hub region includes tab features defining a swage hole, each of the tab features are separated by a slot formed by selectively chemically etching a section of material from the baseplate.
A trace gimbal is described herein. In some embodiments, the trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger, and the rear outrigger includes a distal rear outrigger and a proximal rear outrigger. The trace gimbal further includes a middle strut extending in a width direction of the trace gimbal and adjoining the proximal front outrigger to the rear outrigger, and an inner strut connecting the middle strut to a slider tongue. The inner strut includes a slot, and the inner strut and the middle strut adjoin the outer gimbal struts to the slider tongue.
A hard disk drive (HDD) includes a suspension connected to a stack arm. The suspension includes a mount plate, a hinge, a load beam, and a circuit. The mount plate includes a bottom surface facing a disk and an ear portion extending from a side edge of the mount plate. The bottom surface includes a planar region, a first indented region vertically recessed relative to the planar region, and a second indented region located at the ear portion and vertically recessed relative to the planar region. The load beam terminates in a load beam hinge is connected to the first indented region. The circuit extends along the first and second indented regions.
Examples of a suspension are provided. The suspension includes a mount plate attached to a load beam at a suspension assembly attachment point. The suspension may include a first actuator and a second actuator located at the mount plate. The first actuator is shaped as a non-right angle parallelogram spanning across a first opening in the mount plate. The second actuator is shaped as a non-right angle parallelogram spanning across a second opening in the mount plate. The first and second actuators are configured to deflect the distal end of the mount plate, which causes the load beam to rotate with a rotation center located along the load beam.
G11B 5/52 - Disposition or mounting of heads relative to record carriers with simultaneous movement of head and record carrier, e.g. rotation of head
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
Examples of a suspension are provided. The suspension includes a mount plate attached to a load beam at a suspension assembly attachment point. The suspension may include a first actuator and a second actuator located at the mount plate. The first actuator is shaped as a non-right angle parallelogram spanning across a first opening in the mount plate. The second actuator is shaped as a non-right angle parallelogram spanning across a second opening in the mount plate. The first and second actuators are configured to deflect the distal end of the mount plate, which causes the load beam to rotate with a rotation center located along the load beam.
A hard disk drive (HDD) includes a suspension connected to a stack arm. The suspension includes a mount plate, a hinge, a load beam, and a circuit. The mount plate includes a bottom surface facing a disk and an ear portion extending from a side edge of the mount plate. The bottom surface includes a planar region, a first indented region vertically recessed relative to the planar region, and a second indented region located at the ear portion and vertically recessed relative to the planar region. The load beam terminates in a load beam hinge is connected to the first indented region. The circuit extends along the first and second indented regions.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
A baseplate for a disk drive suspension is provided. The baseplate includes a receiving space at a distal end configured to mate with a spring of a load beam. The receiving space partially extends a length of the baseplate. The baseplate also includes a swage hub at a proximal end and an indented surface surrounding the swage hub. The proximal end is opposite the distal end. The indented surface is at least partially defined by a baseplate support section.
Examples of a head stack assembly arm are described herein. The head stack assembly arm includes a load beam in an upper nesting configuration including a lift tab with an inner edge. The head stack assembly arm includes a load beam in a lower nesting configuration including a lift tab with an inner edge, the inner edge of the load beam in the lower nesting configuration is a different size from the inner edge of the load beam in the upper nesting configuration.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 21/21 - Supporting the headsSupporting the sockets for plug-in heads while the head is in operative position but stationary or permitting minor movements to follow irregularities in surface of record carrier with provision for maintaining desired spacing of head from record carrier, e.g. fluid-dynamic spacing, slider
G11B 21/22 - Supporting the headsSupporting the sockets for plug-in heads while the head is out of operative position
A gimbal assembly includes a frame having base, tip and mount portions, and a crossbar joined to the tip portion by a neck region. Portions of the crossbar and neck region define transition edge regions each extending from a point of minimum width D of the neck region to where the edge of the crossbar becomes substantially straight. Each of the transition edge regions includes a transition length a and a transition width b. The frame comprises an area of interest that includes the neck region and a portion of the crossbar that has a length of 0.6 mm and is centered to the neck region, and has a total area size A, a centroid C and a centroid distance H between the centroid C and a far side of the neck region. The crossbar and neck region have geometries that satisfy a design metric that is less than 0.05.
A trace gimbal is described herein. In some embodiments, the trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger. The rear outrigger includes a distal rear outrigger and a proximal rear outrigger. A middle strut extends in a width direction of the trace gimbal, adjoining the proximal front outrigger to the rear outrigger, and connecting to a slider tongue. The front outrigger includes a strut form bent away from a load beam reference plane at an angle θ. In some embodiments, the outer struts include a second strut form disposed on the rear outrigger. The second strut form can be bent toward the load beam reference plane at the angle θ.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/58 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
G11B 5/60 - Fluid-dynamic spacing of heads from record carriers
A trace gimbal is described herein. In some embodiments, the trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger. The rear outrigger includes a distal rear outrigger and a proximal rear outrigger. A middle strut extends in a width direction of the trace gimbal, adjoining the proximal front outrigger to the rear outrigger, and connecting to a slider tongue. The front outrigger includes a strut form bent away from a load beam reference plane at an angle θ. In some embodiments, the outer struts include a second strut form disposed on the rear outrigger. The second strut form can be bent toward the load beam reference plane at the angle θ.
Examples of a load beam are described herein that include a lifter tab extending towards a distal end, a dustpan defined by a dustpan forming line at a proximal end and the lifter tab at a distal end and a first and second plurality of rail sections separated by a longitudinal axis. The first and second plurality rail sections including a rear rail, an intermediate rail, and a front rail. The rear rail extends from a proximal end of the load beam to the first intermediate rail, the intermediate rail extends from the first rear rail to the dustpan forming line, and the front rail extends from the dustpan forming line to a proximal end of the lifter tab.
Examples of a load beam are described herein that include a lifter tab extending towards a distal end, a dustpan defined by a dustpan forming line at a proximal end and the lifter tab at a distal end and a first and second plurality of rail sections separated by a longitudinal axis. The first and second plurality rail sections including a rear rail, an intermediate rail, and a front rail. The rear rail extends from a proximal end of the load beam to the first intermediate rail, the intermediate rail extends from the first rear rail to the dustpan forming line, and the front rail extends from the dustpan forming line to a proximal end of the lifter tab.
A flexure is described, which includes conductive traces extending from a proximal end of the flexure to a distal end of the flexure. The flexure also includes a plurality of outer gimbal struts configured to define an opening at the proximal end of the flexure. The flexure also includes an oblong feature extending into the opening, the oblong feature defines an aperture. The conductive traces include a first semi-circular conductive trace portion overlapping a first section of the oblong feature at a proximal end of the aperture extending to a distal end of the aperture. The conductive traces include a second semi-circular conductive trace portion overlapping a second section of the oblong feature at a proximal end of the aperture extending to the distal end of the aperture. The first and second semi-circular conductive trace portions define the aperture.
A flexure is described, which includes conductive traces extending from a proximal end of the flexure to a distal end of the flexure. The flexure also includes a plurality of outer gimbal struts configured to define an opening at the proximal end of the flexure. The flexure also includes an oblong feature extending into the opening, the oblong feature defines an aperture. The conductive traces include a first semi-circular conductive trace portion overlapping a first section of the oblong feature at a proximal end of the aperture extending to a distal end of the aperture. The conductive traces include a second semi-circular conductive trace portion overlapping a second section of the oblong feature at a proximal end of the aperture extending to the distal end of the aperture. The first and second semi-circular conductive trace portions define the aperture.
An improved load beam is described herein. In some embodiments, the load beam comprises a major surface including a proximal end and a distal end, the distal end including a tip weld, a dustpan, and a lift tab; side rails extending from the major surface and the dustpan; and a slit disposed on the major surface about the tip weld.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 17/028 - Positioning or locking of single discs of discs rotating during transducing operation
G11B 21/21 - Supporting the headsSupporting the sockets for plug-in heads while the head is in operative position but stationary or permitting minor movements to follow irregularities in surface of record carrier with provision for maintaining desired spacing of head from record carrier, e.g. fluid-dynamic spacing, slider
G11B 33/14 - Reducing influence of physical parameters, e.g. temperature change, moisture, dust
G11B 5/60 - Fluid-dynamic spacing of heads from record carriers
An improved load beam is described herein. In some embodiments, the load beam comprises a major surface including a proximal end and a distal end, the distal end including a tip weld, a dustpan, and a lift tab; side rails extending from the major surface and the dustpan; and a slit disposed on the major surface about the tip weld.
A suspension is described. The suspension includes a base plate and a load beam coupled to the base plate. The base plate includes a distal elongated element and a proximal elongated element. The distal elongated element includes at least one non-straight baseplate edge and the proximal elongated element includes at least one non-straight baseplate edge. The load beam includes a first mounting shelf and a second mounting shelf. The load beam is coupled to the base plate such that the first mounting shelf is exposed adjacent to the distal elongated element, and the second mounting shelf is exposed adjacent to the proximal elongated element. The first and second mounting shelves are configured to receive an actuator, such that an edge of the actuator and the at least one non-straight baseplate edge forms a gap.
A gimbal assembly includes a frame having base, tip and mount portions, and a crossbar joined to the tip portion by a neck region. Portions of the crossbar and neck region define transition edge regions each extending from a point of minimum width D of the neck region to where the edge of the crossbar becomes substantially straight. Each of the transition edge regions includes a transition length a and a transition width b. The frame comprises an area of interest that includes the neck region and a portion of the crossbar that has a length of 0.6 mm and is centered to the neck region, and has a total area size A, a centroid C and a centroid distance H between the centroid C and a far side of the neck region. The crossbar and neck region have geometries that satisfy a design metric that is less than 0.05.
A flexure assembly is described. The flexure assembly includes a gimbal portion on configured to receive a slider. The gimbal portion includes a first surface and a second surface which is opposite to the first surface. The slider is mounted on the second surface. The flexure assembly also includes a pair of microactuator elements. The flexure assembly also includes a tongue of the gimbal portion on which the slider is mounted. The tongue includes a dimple point which represents the center of the tongue. The flexure assembly also includes a pair of first supporting portions and a pair of second supporting portions of the gimbal portion. A pair of end portions are individually secured to the tongue and the first supporting portions and the pair of second supporting portions. The flexure assembly also includes a conductive circuit portion unsupported between a first stationary part and the pair of end portions.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
38.
Hard disk drive gimbal design with high torsion frequencies
A trace gimbal is described herein. In some embodiments, the trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger, and the rear outrigger includes a distal rear outrigger and a proximal rear outrigger. The trace gimbal further includes a middle strut extending in a width direction of the trace gimbal and adjoining the proximal front outrigger to the rear outrigger, and an inner strut connecting the middle strut to a slider tongue. The inner strut and the middle strut adjoin the outer gimbal struts to the slider tongue.
A trace gimbal is described herein. In some embodiments, the trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger, and the rear outrigger includes a distal rear outrigger and a proximal rear outrigger. The trace gimbal further includes a middle strut extending in a width direction of the trace gimbal and adjoining the proximal front outrigger to the rear outrigger, and an inner strut connecting the middle strut to a slider tongue. The inner strut and the middle strut adjoin the outer gimbal struts to the slider tongue.
A trace gimbal is described herein. In some embodiments, the trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger, and the rear outrigger includes a distal rear outrigger and a proximal rear outrigger. The trace gimbal further includes a middle strut extending in a width direction of the trace gimbal and adjoining the proximal front outrigger to the rear outrigger, and an inner strut connecting the middle strut to a slider tongue. The inner strut includes a slot, and the inner strut and the middle strut adjoin the outer gimbal struts to the slider tongue.
A trace gimbal is described herein. In some embodiments, the trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger, and the rear outrigger includes a distal rear outrigger and a proximal rear outrigger. The trace gimbal further includes a middle strut extending in a width direction of the trace gimbal and adjoining the proximal front outrigger to the rear outrigger, and an inner strut connecting the middle strut to a slider tongue. The inner strut includes a slot, and the inner strut and the middle strut adjoin the outer gimbal struts to the slider tongue.
A method of manufacturing a piezoelectric microactuator assembly can include forming a top electrode layer onto a top face of a PZT element and placing a mask at different locations on the top electrode layer. A conductive epoxy can be added in the space between the at least two portions of the mask, and a constraint layer can be applied to the conductive epoxy smaller than the top electrode layer formed on the PZT element. The mask ca be removed, leaving the constraint layer on the conductive epoxy, creating an exposed shelf of the top electrode uncovered by the constraint layer. A bottom electrode layer can be formed onto a bottom face of the PZT element opposite the top electrode layer and the PZT element can be polarized to form an active piezoelectric layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
H10N 30/045 - Treatments to modify a piezoelectric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning by polarising
H10N 30/063 - Forming interconnections, e.g. connection electrodes of multilayered piezoelectric or electrostrictive parts
H10N 30/067 - Forming single-layered electrodes of multilayered piezoelectric or electrostrictive parts
H10N 30/072 - Forming of piezoelectric or electrostrictive parts or bodies on an electrical element or another base by laminating or bonding of piezoelectric or electrostrictive bodies
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
43.
SINGLE LINE DRIVE CIRCUIT ENABLING IDENTICAL ACTUATOR ORIENTATION
A driving circuit is described. The driving circuit includes: a first piezoelectric actuator including at least one piezoelectric element disposed between a first electrode and a second electrode, the first electrode configured to connected to a first ground at a first terminal and the second electrode configured to connected to an amplifier at a second terminal. The driving circuit includes a second piezoelectric actuator including at least one piezoelectric element disposed between a first electrode and a second electrode, the first electrode configured to connected to a control signal at a first terminal and the second electrode connected to a second ground at a second terminal. And, the first terminal of the first piezoelectric actuator and the first terminal of the second piezoelectric actuator are configured such that the first piezoelectric actuator and the second piezoelectric actuator are symmetrical and have similar polarity.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/58 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
G11B 11/105 - Recording on, or reproducing from, the same record carrier wherein for these two operations the methods or means are covered by different main groups of groups or by different subgroups of group Record carriers therefor using recording by magnetisation or demagnetisation using a beam of light or a magnetic field for recording and a beam of light for reproducing, e.g. light-induced thermomagnetic recording or Kerr effect reproducing
G11B 21/10 - Track finding or aligning by moving the head
H01L 41/04 - SEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR - Details thereof - Details of piezo-electric or electrostrictive elements
44.
Single Line Drive Circuit Enabling Identical Actuator Orientation
A driving circuit is described. The driving circuit includes: a first piezoelectric actuator including at least one piezoelectric element disposed between a first electrode and a second electrode, the first electrode configured to connected to a first ground at a first terminal and the second electrode configured to connected to an amplifier at a second terminal. The driving circuit includes a second piezoelectric actuator including at least one piezoelectric element disposed between a first electrode and a second electrode, the first electrode configured to connected to a control signal at a first terminal and the second electrode connected to a second ground at a second terminal. And, the first terminal of the first piezoelectric actuator and the first terminal of the second piezoelectric actuator are configured such that the first piezoelectric actuator and the second piezoelectric actuator are symmetrical and have similar polarity.
H01L 41/04 - SEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR - Details thereof - Details of piezo-electric or electrostrictive elements
A method of manufacturing a piezoelectric microactuator having a wrap-around electrode includes forming a piezoelectric element having a large central electrode on a top face, and having a wrap-around electrode that includes the bottom face, two opposing ends of the device, and two opposing end portions of the top face. The device is then cut through the middle, separating the device into two separate piezoelectric microactuators each having a wrap-around electrode.
A trace gimbal is described. The trace gimbal includes outer struts including a front outrigger at a distal end of the trace gimbal and a rear outrigger at a proximal end of the trace gimbal. The front outrigger includes a distal front outrigger and a proximal front outrigger. The rear outrigger includes a distal rear outrigger and a proximal rear outrigger. The trace gimbal also includes a middle strut extending from the distal rear outrigger and adjoining the proximal front outrigger to the rear outrigger. The middle strut extends from a slider tongue adjoining the outer gimbal struts to the slider tongue.
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
48.
Contact pad with electrical connection structure for connecting a piezoelectric element and an electrical circuit with a conductive adhesive
An electrical connection structure for connecting a piezoelectric element and an electrical circuit to each other with a conductive adhesive is described. The electrical connection structure includes an epoxy, a conductive component surrounded by the epoxy, and a trace feature implemented on top of the electrical connection structure. At least one depression feature can be implemented on top of the electrical connection structure to constrain the epoxy and the at least one conductive component.
H02N 2/02 - Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuatorsLinear positioners
H10N 30/87 - Electrodes or interconnections, e.g. leads or terminals
49.
NON-OPERATIONAL SHOCK MITIGATION FOR A SUSPENSION DEVICE
A flexure is described herein. The flexure includes a slider tongue with a proximal end and a distal end. The sliding tongue including a leading edge at the proximal end prone to contact an undersurface of a load beam attached to the flexure. The flexure also includes a magnetic read/write head slider attached to the slider tongue at the distal end, at least one PZT microactuator affixed to the slider tongue, between the proximal end and the distal end, and at least one dampening device at the leading edge of the slider tongue configured to reduce an impulse during a non-operational shock event and reduce stress on the at least one PZT microactuator.
F16F 7/10 - Vibration-dampersShock-absorbers using inertia effect
F16F 15/00 - Suppression of vibrations in systemsMeans or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
F16F 15/02 - Suppression of vibrations of non-rotating, e.g. reciprocating, systemsSuppression of vibrations of rotating systems by use of members not moving with the rotating system
F16F 15/04 - Suppression of vibrations of non-rotating, e.g. reciprocating, systemsSuppression of vibrations of rotating systems by use of members not moving with the rotating system using elastic means
F16F 15/10 - Suppression of vibrations in rotating systems by making use of members moving with the system
50.
Non-operational shock mitigation for a suspension device
A flexure is described herein. The flexure includes a slider tongue with a proximal end and a distal end. The sliding tongue including a leading edge at the proximal end prone to contact an undersurface of a load beam attached to the flexure. The flexure also includes a magnetic read/write head slider attached to the slider tongue at the distal end, at least one PZT microactuator affixed to the slider tongue, between the proximal end and the distal end, and at least one dampening device at the leading edge of the slider tongue configured to reduce an impulse during a non-operational shock event and reduce stress on the at least one PZT microactuator.
A suspension is described. The suspension includes a base plate and a load beam coupled to the base plate. The base plate includes a distal elongated element and a proximal elongated element. The distal elongated element includes at least one non-straight baseplate edge and the proximal elongated element includes at least one non-straight baseplate edge. The load beam includes a first mounting shelf and a second mounting shelf. The load beam is coupled to the base plate such that the first mounting shelf is exposed adjacent to the distal elongated element, and the second mounting shelf is exposed adjacent to the proximal elongated element. The first and second mounting shelves are configured to receive an actuator, such that an edge of the actuator and the at least one non-straight baseplate edge forms a gap.
A suspension is described. The suspension includes a base plate and a load beam coupled to the base plate. The base plate includes a distal elongated element and a proximal elongated element. The distal elongated element includes at least one non-straight baseplate edge and the proximal elongated element includes at least one non-straight baseplate edge. The load beam includes a first mounting shelf and a second mounting shelf. The load beam is coupled to the base plate such that the first mounting shelf is exposed adjacent to the distal elongated element, and the second mounting shelf is exposed adjacent to the proximal elongated element. The first and second mounting shelves are configured to receive an actuator, such that an edge of the actuator and the at least one non-straight baseplate edge forms a gap.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/00 - Recording by magnetisation or demagnetisation of a record carrierReproducing by magnetic meansRecord carriers therefor
G11B 5/54 - Disposition or mounting of heads relative to record carriers with provision for moving the head into, or out of, its operative position or across tracks
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
53.
MULTI-LAYER PZT MICROACUATOR WITH ACTIVE PZT CONSTRAINING LAYERS FOR A DSA SUSPENSION
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
A baseplate for a disk drive suspension is provided. The baseplate includes a receiving space at a distal end configured to mate with a spring of a load beam. The receiving space partially extends a length of the baseplate. The baseplate also includes a swage hub at a proximal end and an indented surface surrounding the swage hub. The proximal end is opposite the distal end. The indented surface is at least partially defined by a baseplate support section.
A baseplate for a disk drive suspension is provided. The baseplate includes a receiving space at a distal end configured to mate with a spring of a load beam. The receiving space partially extends a length of the baseplate. The baseplate also includes a swage hub at a proximal end and an indented surface surrounding the swage hub. The proximal end is opposite the distal end. The indented surface is at least partially defined by a baseplate support section.
A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer thereby reducing or eliminating bending of the assembly as installed in an environment, thereby increasing the effective stroke length of the assembly. Poling only a single layer would induce stresses into the device; hence, polling both piezoelectric layers even though only one layer will be active in use reduces stresses in the device and therefore increases reliability.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/56 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of adjusting the position of the head relative to the record carrier, e.g. manual adjustment for azimuth correction or track centering
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
H10N 30/03 - Assembling devices that include piezoelectric or electrostrictive parts
H10N 30/045 - Treatments to modify a piezoelectric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning by polarising
H10N 30/063 - Forming interconnections, e.g. connection electrodes of multilayered piezoelectric or electrostrictive parts
H10N 30/067 - Forming single-layered electrodes of multilayered piezoelectric or electrostrictive parts
H10N 30/072 - Forming of piezoelectric or electrostrictive parts or bodies on an electrical element or another base by laminating or bonding of piezoelectric or electrostrictive bodies
57.
Tri-stage design for actuator attachment on flexure
A method of manufacturing a tri-stage assembly is described herein. The method includes attaching a first microactuator and a second microactuator to a trace gimbal to a flexure during a PZT on flexure process (POF). The first microactuator is located at a distal end of the flexure and the second microactuator located at a proximal end of the flexure. The method also includes welding the trace gimbal to a baseplate, and a load beam to secure the trace gimbal including the first microactuator and the second microactuator.
A piezoelectric (PZT) actuator assembly having a fixed-end and a hinged-end is provided. The assembly includes a first side electrode at the hinge-end, and a second side electrode at the fixed-end. The assembly includes a third piezoelectric layer including a top surface and a bottom surface disposed over the top surface of the second PZT layer. A fourth electrode is at least partially disposed on the top surface of the third PZT layer. The fourth electrode is connected to the second side electrode at the fixed-end.
A piezoelectric (PZT) actuator assembly having a fixed-end and a hinged-end is provided. The assembly includes a first side electrode at the hinge-end, and a second side electrode at the fixed-end. The assembly includes a third piezoelectric layer including atop surface and a bottom surface disposed over the top surface of the second PZT layer. A fourth electrode is at least partially disposed on the top surface of the third PZT layer. The fourth electrode is connected to the second side electrode at the fixed-end.
A method of manufacturing a tri-stage assembly is provided. The method includes attaching a first microactuator and a second microactuator to a trace gimbal to a flexure during a PZT on flexure process (POF). The first microactuator is located at a distal end of the flexure and the second microactuator located at a proximal end of the flexure. The method also includes welding the trace gimbal to a baseplate, and a load beam to secure the trace gimbal including the first microactuator and the second microactuator.
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
A dielectric layer configured to overlay a spring metal layer in a suspension assembly is described. The dielectric layer includes a tongue portion including a proximate end and a distal end, trace portions extending from the tongue portion, and an aperture aligned with the void and defined by the tongue portion. The aperture includes an elongated opening with opposing ends partially aligning with the central opening of the void. The aperture further includes slits extending from the opposing ends of the elongated opening and at least partially aligned with slits of the void in the spring metal layer.
A dielectric layer configured to overlay a spring metal layer in a suspension assembly is described. The dielectric layer includes a tongue portion including a proximate end and a distal end, trace portions extending from the tongue portion, and an aperture aligned with the void and defined by the tongue portion. The aperture includes an elongated opening with opposing ends partially aligning with the central opening of the void. The aperture further includes slits extending from the opposing ends of the elongated opening and at least partially aligned with slits of the void in the spring metal layer.
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
A flexure assembly is described. The flexure assembly includes a gimbal portion on configured to receive a slider. The gimbal portion includes a first surface and a second surface which is opposite to the first surface. The slider is mounted on the second surface. The flexure assembly also includes a pair of microactuator elements. The flexure assembly also includes a tongue of the gimbal portion on which the slider is mounted. The tongue includes a dimple point which represents the center of the tongue. The flexure assembly also includes a pair of first supporting portions and a pair of second supporting portions of the gimbal portion. A pair of end portions are individually secured to the tongue and the first supporting portions and the pair of second supporting portions. The flexure assembly also includes a conductive circuit portion unsupported between a first stationary part and the pair of end portions.
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
65.
Multi-layer microactuators for hard disk drive suspensions
A multi-layer microactuator for a hard disk drive suspension includes a piezoelectric (“PZT”) layer, a constraining layer, a lower electrode layer, a middle electrode layer, and an upper electrode layer. The lower electrode layer is on a bottom surface of the PZT layer and includes a first lower electrode island, a second lower electrode island, and a third lower electrode island. The second lower electrode island includes a finger extending from a main body portion towards a first end of the PZT layer. The middle electrode layer is disposed between a top surface of the PZT layer and a bottom surface of the constraining layer. The middle electrode layer including a first middle electrode island and a second middle electrode island, the second middle electrode island including a finger extending from a main body portion towards the first end of the PZT layer.
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
67.
Multi-layer PZT microacuator with active PZT constraining layers for a DSA suspension
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
An electrical connection structure for connecting a piezoelectric element and an electrical circuit to each other with a conductive adhesive is described. The electrical connection structure includes an epoxy, a conductive component surrounded by the epoxy, and a trace feature implemented on top of the electrical connection structure.
H02N 2/02 - Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuatorsLinear positioners
69.
Multilayer PZT electrode configuration for suspension stroke increase
A piezoelectric actuator assembly is described. The assembly including a first layer including a top and a bottom surfaces. The assembly including a second layer having a top and a bottom surfaces, the bottom surface of the second layer is disposed over the top surface of the first layer. The assembly including a third layer having a top and a bottom surfaces, the bottom surface of the third layer is disposed over the top surface of the second layer. The assembly includes a first electrode, a second electrode, a third electrode, and a fourth electrode. The third electrode is configured to be shorter than the second electrode such that the active PZT length of the second layer and the third layer is shorter than the active PZT length of the first layer.
A method of manufacturing a piezoelectric microactuator having a wrap-around electrode includes forming a piezoelectric element having a large central electrode on a top face, and having a wrap-around electrode that includes the bottom face, two opposing ends of the device, and two opposing end portions of the top face. The device is then cut through the middle, separating the device into two separate piezoelectric microactuators each having a wrap-around electrode.
A method of assembly a dual stage actuated suspension includes either applying an adhesive to a microactuator motor and then B-staging the adhesive, or applying an adhesive that has already been B-staged such as in film adhesive form to the microactuator then assembling the microactuator into a suspension and then finishing the adhesive cure. The adhesive can be applied to bulk piezoelectric material, with the adhesive being B-staged either before or after it is applied to the bulk piezoelectric material, and the piezoelectric material then singulated into a number of individual piezoelectric microactuators. The method allows greater control over how much adhesive is used, and greater control over spread of that adhesive and control over potential contamination, than traditional liquid epoxy dispense methods.
G11B 5/00 - Recording by magnetisation or demagnetisation of a record carrierReproducing by magnetic meansRecord carriers therefor
H01L 41/00 - SEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR - Details thereof
B32B 38/00 - Ancillary operations in connection with laminating processes
B32B 37/00 - Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
G11B 21/00 - Head arrangements not specific to the method of recording or reproducing
G11B 5/48 - Disposition or mounting of heads relative to record carriers
H01L 41/297 - Individual layer electrodes of multilayered piezo-electric or electrostrictive parts
H01L 41/33 - Shaping or machining of piezo-electric or electrostrictive bodies
G11B 5/56 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of adjusting the position of the head relative to the record carrier, e.g. manual adjustment for azimuth correction or track centering
A suspension assembly is described. The suspension assembly includes a load beam, the load beam includes a first set of spring extensions connecting a rigid region and a mounting region of the load beam. The suspension assembly also includes a base plate coupled to the mounting region of the load beam. The base plate includes two hinge members, each of the hinge members includes a second spring extension connected to the first set of spring extensions and coupling the load beam and the base plate. The base plate also includes a bender on a first side of the load beam connected to one of the two hinge members predisposing the rigid region to move from a first position to a second position.
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
74.
Disk drive suspension tri-stage actuator with single side actuator attach
A tri-stage actuated disk drive suspension is described. The tri-stage actuated disk drive suspension including a beam and a gimbal attached to the beam. The gimbal is configured to receive a first actuator to mount on a first surface of the suspension near a first lateral side of the suspension and is configured to receive a second actuator to mount on the first surface of the gimbal near a second lateral side of the suspension. The gimbal is configured to receive a head slider to mount on the first surface of the suspension. And, the tri-stage actuated disk drive suspension including a baseplate having the beam attached thereto. The baseplate configured to receive a third actuator from the first surface of the suspension to mount on a pair of shelves.
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
75.
Assembly of DSA suspensions using microactuators with partially cured adhesive
A method of assembly a dual stage actuated suspension includes either applying an adhesive to a microactuator motor and then B-staging the adhesive, or applying an adhesive that has already been B-staged such as in film adhesive form to the microactuator then assembling the microactuator into a suspension and then finishing the adhesive cure. The adhesive can be applied to bulk piezoelectric material, with the adhesive being B-staged either before or after it is applied to the bulk piezoelectric material, and the piezoelectric material then singulated into a number of individual piezoelectric microactuators. The method allows greater control over how much adhesive is used, and greater control over spread of that adhesive and control over potential contamination, than traditional liquid epoxy dispense methods.
A multi-layer microactuator for a hard disk drive suspension includes a piezoelectric (“PZT”) layer, a constraining layer, a lower electrode layer, a middle electrode layer, and an upper electrode layer. The lower electrode layer is on a bottom surface of the PZT layer and includes a first lower electrode island, a second lower electrode island, and a third lower electrode island. The second lower electrode island includes a finger extending from a main body portion towards a first end of the PZT layer. The middle electrode layer is disposed between a top surface of the PZT layer and a bottom surface of the constraining layer. The middle electrode layer including a first middle electrode island and a second middle electrode island, the second middle electrode island including a finger extending from a main body portion towards the first end of the PZT layer.
A dual stage actuated suspension has a first piezoelectric microactuator on the trace gimbal assembly (TGA), and a pseudo feature located laterally opposite the microactuator. The pseudo feature is formed integrally with the TGA from at least one of the base metal layer, the insulative layer, and the conductive layer that make up the TGA. The pseudo feature helps to balance the suspension. The suspension can optionally have a second microactuator located proximal of the first microactuator in order to perform coarser positioning than the first microactuator, such that the suspension is a tri-stage actuated suspension.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
78.
Manufacturing method for multi-layer PZT microactuator having a poled but inactive PZT constraining layer
A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
H01L 41/293 - Connection electrodes of multilayered piezo-electric or electrostrictive parts
G11B 5/56 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of adjusting the position of the head relative to the record carrier, e.g. manual adjustment for azimuth correction or track centering
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
H01L 41/25 - Assembling devices that include piezo-electric or electrostrictive parts
H01L 41/257 - Treating devices or parts thereof to modify a piezo-electric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning by polarising
H01L 41/312 - Applying piezo-electric or electrostrictive parts or bodies onto an electrical element or another base by laminating or bonding of piezo-electric or electrostrictive bodies
H01L 41/297 - Individual layer electrodes of multilayered piezo-electric or electrostrictive parts
79.
Partial etched polyimide for non-conductive adhesive containment
Embodiments of an adhesive containment structure are provided herein. The suspension includes a base portion that includes a metal support layer, an insulation layer including an insulating material on the metal support layer, and a signal conductor layer. The suspension includes a gimbaled portion, a microactuator adhered to the support layer. The suspension also includes an adhesive containment structure, the adhesive containment structure includes a first portion of the insulating material, a second portion of the insulating material, and a third portion of the insulating material, the first and second portions of the insulating material being separated by a gap, and the third portion of the insulating material disposed within the gap. Adhesive is disposed within the gap of the adhesive containment structure, the adhesive adhering the microactuator to the third portion of the insulating material.
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
81.
Pseudo feature configured as a damper for a disk-drive suspension
A pseudo feature for a suspension and method of manufacture are described. The pseudo feature for a suspension includes a first constraining layer; a second constraining layer; and a damping layer arranged between the first constraining layer and the second constraining layer.
F16F 15/02 - Suppression of vibrations of non-rotating, e.g. reciprocating, systemsSuppression of vibrations of rotating systems by use of members not moving with the rotating system
B32B 3/26 - Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shapeLayered products comprising a layer having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layerLayered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shapeLayered products comprising a layer having particular features of form characterised by a layer with cavities or internal voids
A multi-level piezoelectric actuator is manufactured using wafer level processing. Two PZT wafers are formed and separately metallized for electrodes. The metallization on the second wafer is patterned, and holes that will become electrical vias are formed in the second wafer. The wafers are then stacked and sintered, then the devices are poled as a group and then singulated to form nearly complete individual PZT actuators. Conductive epoxy is added into the holes at the product placement step in order to both adhere the actuator within its environment and to complete the electrical via thus completing the device. Alternatively: the first wafer is metallized; then the second wafer having holes therethrough but no metallization is stacked and sintered to the first wafer; and patterned metallization is applied to the second wafer to both form electrodes and to complete the vias. The devices are then poled as a group, and singulated.
H01L 41/27 - Manufacturing multilayered piezo-electric or electrostrictive devices or parts thereof, e.g. by stacking piezo-electric bodies and electrodes
H01L 41/338 - Shaping or machining of piezo-electric or electrostrictive bodies by machining by cutting or dicing
H01L 41/273 - Manufacturing multilayered piezo-electric or electrostrictive devices or parts thereof, e.g. by stacking piezo-electric bodies and electrodes by integrally sintering piezo-electric or electrostrictive bodies and electrodes
H01L 41/09 - Piezo-electric or electrostrictive elements with electrical input and mechanical output
H01L 41/053 - Mounts, supports, enclosures or casings
H01L 41/277 - Manufacturing multilayered piezo-electric or electrostrictive devices or parts thereof, e.g. by stacking piezo-electric bodies and electrodes by stacking bulk piezo-electric or electrostrictive bodies and electrodes
H03H 3/08 - Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of resonators or networks using surface acoustic waves
H01L 41/312 - Applying piezo-electric or electrostrictive parts or bodies onto an electrical element or another base by laminating or bonding of piezo-electric or electrostrictive bodies
83.
Disk drive suspension tri-stage actuator having pseudo feature integrally constructed on trace gimbal
A dual stage actuated suspension has a first piezoelectric microactuator on the trace gimbal assembly (TGA), and a pseudo feature located laterally opposite the microactuator. The pseudo feature is formed integrally with the TGA from at least one of the base metal layer, the insulative layer, and the conductive layer that make up the TGA. The pseudo feature helps to balance the suspension. The suspension can optionally have a second microactuator located proximal of the first microactuator in order to perform coarser positioning than the first microactuator, such that the suspension is a tri-stage actuated suspension.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
84.
Flexure assembly configured to reduce electrical coupling and maintain a high signal bandwidth
In a disk drive having a flexible circuit tail that is routed within a recess in the actuator arm, a dielectric spacer is added to the top of the tail in order to space the circuit traces within the tail further away from the electrically conductive actuator arm, and to make more repeatable that spacing. The added spacing reduces electrical coupling and thus increases the bandwidth of the circuit. The spacer can be in the form of a section of the same viscoelastic material that is used elsewhere as a vibration dampener on the suspension, the viscoelastic material being adhered to the tail before the tail is inserted within the recess. Alternatively, the spacer can be a thickened region of the flexible circuit covercoat in the area where the tail will reside within the recess.
A multi-level piezoelectric actuator is manufactured using wafer level processing. Two PZT wafers are formed and separately metallized for electrodes. The metallization on the second wafer is patterned, and holes that will become electrical vias are formed in the second wafer. The wafers are then stacked and sintered, then the devices are poled as a group and then singulated to form nearly complete individual PZT actuators. Conductive epoxy is added into the holes at the product placement step in order to both adhere the actuator within its environment and to complete the electrical via thus completing the device. Alternatively: the first wafer is metallized; then the second wafer having holes therethrough but no metallization is stacked and sintered to the first wafer; and patterned metallization is applied to the second wafer to both form electrodes and to complete the vias. The devices are then poled as a group, and singulated.
H01L 41/27 - Manufacturing multilayered piezo-electric or electrostrictive devices or parts thereof, e.g. by stacking piezo-electric bodies and electrodes
H01L 41/338 - Shaping or machining of piezo-electric or electrostrictive bodies by machining by cutting or dicing
H01L 41/273 - Manufacturing multilayered piezo-electric or electrostrictive devices or parts thereof, e.g. by stacking piezo-electric bodies and electrodes by integrally sintering piezo-electric or electrostrictive bodies and electrodes
H01L 41/083 - Piezo-electric or electrostrictive elements having a stacked or multilayer structure
H01L 41/09 - Piezo-electric or electrostrictive elements with electrical input and mechanical output
H01L 41/053 - Mounts, supports, enclosures or casings
H01L 41/277 - Manufacturing multilayered piezo-electric or electrostrictive devices or parts thereof, e.g. by stacking piezo-electric bodies and electrodes by stacking bulk piezo-electric or electrostrictive bodies and electrodes
H03H 3/08 - Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of resonators or networks using surface acoustic waves
86.
Multi-layer PZT microactuator with active PZT constraining layer for a DSA suspension
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.
In a disk drive having a flexible circuit tail that is routed within a recess in the actuator arm, a dielectric spacer is added to the top of the tail in order to space the circuit traces within the tail further away from the electrically conductive actuator arm, and to make more repeatable that spacing. The added spacing reduces electrical coupling and thus increases the bandwidth of the circuit. The spacer can be in the form of a section of the same viscoelastic material that is used elsewhere as a vibration dampener on the suspension, the viscoelastic material being adhered to the tail before the tail is inserted within the recess. Alternatively, the spacer can be a thickened region of the flexible circuit covercoat in the area where the tail will reside within the recess.
A vibration damper for a disk drive suspension includes a viscoelastic damping layer, a substantially stiffer polymer constraining layer, and a metal layer interposed between the viscoelastic layer and the polymer constraining layer, such as a thin layer of aluminum vapor deposited onto the polymer constraining layer. The metal layer hides irregularities in the viscoelastic layer as that viscoelastic layer is adhered to the suspension without introducing potentially contaminating mineral particles into the polymer constraining layer.
B32B 27/08 - Layered products essentially comprising synthetic resin as the main or only constituent of a layer next to another layer of a specific substance of synthetic resin of a different kind
B32B 7/12 - Interconnection of layers using interposed adhesives or interposed materials with bonding properties
B32B 37/26 - Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers with at least one layer which influences the bonding during the laminating process, e.g. release layers or pressure equalising layers
B32B 37/12 - Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by using adhesives
F16F 15/04 - Suppression of vibrations of non-rotating, e.g. reciprocating, systemsSuppression of vibrations of rotating systems by use of members not moving with the rotating system using elastic means
G11B 3/12 - Supporting in balanced, counterbalanced, or loaded operative position, e.g. loading in direction of traverse
89.
Method of manufacturing piezoelectric microactuators having wrap-around electrodes
A method of manufacturing a piezoelectric microactuator having a wrap-around electrode includes forming a piezoelectric element having a large central electrode on a top face, and having a wrap-around electrode that includes the bottom face, two opposing ends of the device, and two opposing end portions of the top face. The device is then cut through the middle, separating the device into two separate piezoelectric microactuators each having a wrap-around electrode.
H01L 41/29 - Forming electrodes, leads or terminal arrangements
H01L 41/338 - Shaping or machining of piezo-electric or electrostrictive bodies by machining by cutting or dicing
G11B 5/48 - Disposition or mounting of heads relative to record carriers
B32B 38/00 - Ancillary operations in connection with laminating processes
G11B 5/56 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of adjusting the position of the head relative to the record carrier, e.g. manual adjustment for azimuth correction or track centering
In a gimbal dual stage actuated (GSA) suspension for a disk drive, a viscoelastic damper is disposed between and adhered to the suspension's PZT microactuator and the flexure trace gimbal. The damper is dispensed in fluid form onto the trace gimbal during assembly of the suspension, the PZT is placed onto the damper, and the damper is then hardened leaving it adhered to both the PZT and the trace gimbal. The damper reduces peaks in the frequency response of the PZT actuation, thus allowing higher bandwidth of the servo control loop and increasing the effective read and write speeds for the suspension.
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 33/08 - Insulation or absorption of undesired vibrations or sounds
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
91.
Dual stage actuated suspension having shear-mode PZT actuators for rotating gimbal tongue
A dual stage actuated (DSA) suspension uses two shear-mode PZT microactuators to finely position the head slider. The bottom surfaces of the PZTs are affixed to the flexure, and the PZT top surfaces move forward and backward, respectively, in push-pull fashion when the PZTs are activated. Flexible connector arms attach the tops surfaces of the PZTs to the gimbal tongue such that activating the PZTs causes the gimbal tongue to rotate, with the connector arms acting as levers to magnify the motion such that a relatively small shear movement of the PZTs results in a significantly larger lateral movement of the head slider across the data disk.
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/60 - Fluid-dynamic spacing of heads from record carriers
92.
Disk drive suspension having stamped base plate distal tip
A suspension baseplate is stamped at its distal end to which the load beam is mounted. The stamping operation smoothes out roughness in the edge of the baseplate and lowers its height slightly so that, along the line on the baseplate which last contacts the load beam as the load beam is leaving the baseplate, that line on the baseplate is smooth and free of burrs and similar defects. By eliminating burrs on the surface to which the load beam is mounted, variations in the pitch and twist of the load beam are reduced.
A method of manufacturing a piezoelectric microactuator having a wrap-around electrode includes forming a piezoelectric element having a large central electrode on a top face, and having a wrap-around electrode that includes the bottom face, two opposing ends of the device, and two opposing end portions of the top face. The device is then cut through the middle, separating the device into two separate piezoelectric microactuators each having a wrap-around electrode.
In a gimbal dual stage actuated (GSA) suspension for a disk drive, a viscoelastic damper is disposed between and adhered to the suspension's PZT microactuator and the flexure trace gimbal. The damper is dispensed in fluid form onto the trace gimbal during assembly of the suspension, the PZT is placed onto the damper, and the damper is then hardened leaving it adhered to both the PZT and the trace gimbal. The damper reduces peaks in the frequency response of the PZT actuation, thus allowing higher bandwidth of the servo control loop and increasing the effective read and write speeds for the suspension.
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 33/08 - Insulation or absorption of undesired vibrations or sounds
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
95.
Disk drive suspension tri-stage actuator having pseudo feature integrally constructed on trace gimbal
A dual stage actuated suspension has a first piezoelectric microactuator on the trace gimbal assembly (TGA), and a pseudo feature located laterally opposite the microactuator. The pseudo feature is formed integrally with the TGA from at least one of the base metal layer, the insulative layer, and the conductive layer that make up the TGA. The pseudo feature helps to balance the suspension. The suspension can optionally have a second microactuator located proximal of the first microactuator in order to perform coarser positioning than the first microactuator, such that the suspension is a tri-stage actuated suspension.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
96.
Suspension having a stacked D33 mode PZT actuator with constraint layer
A microactuator for a dual stage actuated suspension for a hard disk drive is constructed as a longitudinal stack of piezoelectric (PZT) elements acting in the d33 mode, expanding or contracting longitudinally when an electric field is applied across them in the longitudinal direction. The microactuator has interlaced electrode fingers that separate and define the individual PZT elements, and apply the electric field. A stiff constraint layer having a high Young's modulus is affixed to the microactuator on the side opposite the suspension to which the microactuator is bonded. The constraint layer may be a layer of substantially inactive PZT material that is formed integrally with the PZT elements but without electrodes in the inactive PZT layer. The presence of the stiff constraint layer increases the effective stroke length of the microactuator.
H02N 2/02 - Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuatorsLinear positioners
97.
Dual stage actuated suspension having shear-mode PZT actuators for rotating gimbal tongue
A dual stage actuated (DSA) suspension uses two shear-mode PZT microactuators to finely position the head slider. The bottom surfaces of the PZTs are affixed to the flexure, and the PZT top surfaces move forward and backward, respectively, in push-pull fashion when the PZTs are activated. Flexible connector arms attach the tops surfaces of the PZTs to the gimbal tongue such that activating the PZTs causes the gimbal tongue to rotate, with the connector arms acting as levers to magnify the motion such that a relatively small shear movement of the PZTs results in a significantly larger lateral movement of the head slider across the data disk.
G11B 5/596 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/60 - Fluid-dynamic spacing of heads from record carriers
98.
Disk drive suspension having stamped base plate distal tip
A suspension baseplate is stamped at its distal end to which the load beam is mounted. The stamping operation smoothes out roughness in the edge of the baseplate and lowers its height slightly so that, along the line on the baseplate which last contacts the load beam as the load beam is leaving the baseplate, that line on the baseplate is smooth and free of burrs and similar defects. By eliminating burrs on the surface to which the load beam is mounted, variations in the pitch and twist of the load beam are reduced.
A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer thereby reducing or eliminating bending of the assembly as installed in an environment, thereby increasing the effective stroke length of the assembly. Poling only a single layer would induce stresses into the device; hence, polling both piezoelectric layers even though only one layer will be active in use reduces stresses in the device and therefore increases reliability.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
G11B 5/56 - Disposition or mounting of heads relative to record carriers with provision for moving the head for the purpose of adjusting the position of the head relative to the record carrier, e.g. manual adjustment for azimuth correction or track centering
G11B 5/55 - Track change, selection, or acquisition by displacement of the head
100.
Multi-layer shear mode PZT microactuator for a disk drive suspension, and method of manufacturing same
A microactuator for a suspension is described. The microactuator includes a multi-layer PZT device having a first face and an opposite second face. Each layer of the multi-layer PZT device is configured to operate in its d15 mode when actuated by an actuation voltage. The layers are configured as a stack such that each layer is configured to act in the same direction when actuated such that the first face moves in shear relative to the second face.
G11B 5/48 - Disposition or mounting of heads relative to record carriers
H01L 41/083 - Piezo-electric or electrostrictive elements having a stacked or multilayer structure
H01L 41/09 - Piezo-electric or electrostrictive elements with electrical input and mechanical output
H01L 41/277 - Manufacturing multilayered piezo-electric or electrostrictive devices or parts thereof, e.g. by stacking piezo-electric bodies and electrodes by stacking bulk piezo-electric or electrostrictive bodies and electrodes
patents
