Abstract

Inductive position sensors for sensing relative position (e.g., relative rotary position) between members are provided. In one example implementation, the inductive position sensor includes a transmit aerial having at least one transmit winding. The inductive position sensor can include a receive aerial having one or more receive windings. The inductive position sensor can include a coupling element operable to be disposed on the second member. The inductive position sensor can include processing circuitry configured to provide one or more signals indicative of the position of the first member relative to the second member based on current induced in the one or more receive windings resulting from an oscillating signal provided to the transmit winding. The inductive position sensor includes at least one electrostatic shield. The electrostatic shield can include a plurality of conductive traces arranged so that no current loops are formed in the electrostatic shield.

IPC Classes  ?

• G01D 5/20 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature

Abstract

Position sensing apparatus is provided. In one example implementation, the position sensing apparatus comprises a first member having an excitation conductive winding and a detection conductive winding formed thereon, and a second member having a resonant circuit formed thereon. An integrated circuit comprising excitation signal generation and detection signal processing circuitry is arranged to generate an alternating excitation signal at a resonant frequency of the resonant circuit and to process an alternating detection signal induced in the detection conductive winding as a result of a magnetic field generated by the alternating excitation signal flowing through the detection conductive winding, and the excitation conductive winding and the detection conductive winding are arranged so that the detection signal varies in dependence on the relative position of the first and second member. Phase-shift circuitry is arranged to introduce a phase shift to one of the excitation signal and the detection signal such that the excitation signal output by the integrated circuit and the detection signal input to the detection circuit are in phase or in anti-phase with each other.

IPC Classes  ?

• G01D 5/22 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature differentially influencing two coils
• G01D 5/20 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature

Abstract

Rotary position sensors are provided. In one example implementation, a rotary position sensor can include a first member and a second member, one of the first and second members having a transmit aerial and a receive aerial and the other of the first and second members having an intermediate coupling element. The receive aerial has at least one receive conductive winding arranged to form a first set of current loops and a second set of current loops. The intermediate coupling element comprises a conductive material arranged in a pattern. The pattern of the intermediate coupling element and the layout of the first and second set of current loops are mutually arranged such that any electromotive force induced in the first set of current loops by a background magnetic field is substantially balanced by an electromotive force induced in the second set of current loops by the background magnetic field.

IPC Classes  ?

• G01D 5/22 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature differentially influencing two coils

Abstract

Non-visible objects which differ in their physical properties from their surroundings by association with a variable strength magnetic field may be detected by a suitable array of sensors which can be moved relative to the object in question. By analyzing the signals from the plurality of the sensors in the array, the position of the object can be deduced relative to the array and the array moved to enable a machining guide thereon to be aligned with the non-visible object. The system is of particular value in locating apertures in wing spars when attempting to fix the skin of the wing on to them where it is important to be able to locate the correct point at which to drill a hole through the skin to coincide with the hole in the spar. By defining a magnetic field in the vicinity of the hole to identify the hole magnetically and using an array of magnetic field sensors in a base with an aperture, it is possible to shift the array so that the aperture is precisely aligned with the non-visible hole.

IPC Classes  ?

• G01B 7/14 - Measuring arrangements characterised by the use of electric or magnetic techniques for measuring distance or clearance between spaced objects or spaced apertures
• G01V 3/15 - Electric or magnetic prospecting or detectingMeasuring magnetic field characteristics of the earth, e.g. declination or deviation specially adapted for use during transport, e.g. by a person, vehicle or boat
• B21J 15/28 - Control devices specially adapted to riveting machines not restricted to one of the preceding subgroups
• B21J 15/44 - Rivet hole positioners
• G01D 5/14 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage