A method for molding a hollow molded article, which can suppress deformation of a preform and shorten a molding cycle of the hollow molded article, and a stretching rod and an injection stretch blow molding machine used in the method are provided. The method for molding a hollow molded article, includes: an injection molding process of injection molding a preform; and a blow molding process of obtaining a hollow molded article by stretch blow molding the preform in a blow molding section. The blow molding process includes a preform supporting step of inserting a distal end portion of a stretching rod into the preform and bringing the distal end portion into contact with the preform to support the preform, and a preform separation step of supplying blow air into the preform to release the contact between the preform and the distal end portion.
A method for molding a hollow molded article, which can suppress deformation of a preform and shorten a molding cycle of the hollow molded article, and a stretching rod and an injection stretch blow molding machine used in the method are provided. The method for molding a hollow molded article, includes: an injection molding process of injection molding a preform; and a blow molding process of obtaining a hollow molded article by stretch blow molding the preform in a blow molding section. The blow molding process includes a preform supporting step of inserting a distal end portion of a stretching rod into the preform and bringing the distal end portion into contact with the preform to support the preform, and a preform separation step of supplying blow air into the preform to release the contact between the preform and the distal end portion.
Provided are a screw head capable of enhancing agitating performance in the vicinity of an injection position, an injection device, and an injection stretch blow molding machine using the same. The screw head includes a head having a substantially conical shape, a neck portion integrally formed in one axial direction of the head, and a connecting portion integrally formed in one axial direction of the neck portion. In the screw head, the head has a plurality of agitating blades that protrude outward from an axial center of the head in a radial direction and are formed at intervals in a circumferential direction, the agitating blades each have side wall surfaces that extend in the radial direction and a surface that coincides with the circumferential direction, and an acute angle is formed at an intersection of the side wall surface and the surface.
B29C 49/42 - Component parts, details or accessoriesAuxiliary operations
B29C 69/02 - Combinations of shaping techniques not provided for in a single one of main groups , e.g. associations of moulding and joining techniquesApparatus therefor of moulding techniques only
7.
SCREW HEAD, INJECTION DEVICE, AND INJECTION STRETCH BLOW MOLDING MACHINE USING THE SAME
Provided are a screw head capable of enhancing agitating performance in the vicinity of an injection position, an injection device, and an injection stretch blow molding machine using the same. The screw head includes a head having a substantially conical shape, a neck portion integrally formed in one axial direction of the head, and a connecting portion integrally formed in one axial direction of the neck portion. In the screw head, the head has a plurality of agitating blades that protrude outward from an axial center of the head in a radial direction and are formed at intervals in a circumferential direction, the agitating blades each have side wall surfaces that extend in the radial direction and a surface that coincides with the circumferential direction, and an acute angle is formed at an intersection of the side wall surface and the surface.
When a preform having been molded while released from a mold at an earlier timing in an injection stretch blow molding machine is stretched and blow molded, the bottom of the preform is prevented from rupturing and the bottom of a hollow molded article is prevented from being uneven in wall thickness to produce such a hollow molded article without defect bottom by the injection stretch blow molding machine. An injection molding process of injection molding a preform; and a blow molding process of blow molding the preform to obtain a hollow molded article. The blow molding process allows a tip of a stretching rod cooled to a temperature between 50 C and 90 C to be brought into contact with the bottom of the preform in a softened state, and to press down the bottom of the preform while the bottom is cooled.
When a preform having been molded while released from a mold at an earlier timing in an injection stretch blow molding machine is stretched and blow molded, the bottom of the preform is prevented from rupturing and the bottom of a hollow molded article is prevented from being uneven in wall thickness to produce such a hollow molded article without defect bottom by the injection stretch blow molding machine. An injection molding process of injection molding a preform; and a blow molding process of blow molding the preform to obtain a hollow molded article. The blow molding process allows a tip of a stretching rod cooled to a temperature between 50° C. and 90° C. to be brought into contact with the bottom of the preform in a softened state, and to press down the bottom of the preform while the bottom is cooled.
B29C 49/22 - Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mouldApparatus therefor using multilayered preforms or parisons
B29C 49/64 - Heating or cooling preforms, parisons or blown articles
B29C 49/02 - Combined blow-moulding and manufacture of the preform or the parison
A blow mold high-pressure switching step in a blow molding process of an injection stretch blow molding machine is arranged at the first half portion of the blow molding process, to shorten the injection molding process and improve the moldability. The blow mold high-pressure switching step 61B3 of increasing a mold clamping force for blow molds which have been closed in a blow molding process 61B is configured to be performed at a timing within a time from the start of the upper/lower mold opening step 62A1 for opening upper and lower molds in the injection molding process 62A to release a preform 3P to the completion of the injection mold high-pressure switching step 62A3 for increasing the mold clamping force for the closed injection molding mold.
A blow mold high-pressure switching step in a blow molding process of an injection stretch blow molding machine is arranged at the first half portion of the blow molding process, to shorten the injection molding process and improve the moldability. The blow mold high-pressure switching step 61B3 of increasing a mold clamping force for blow molds which have been closed in a blow molding process 61B is configured to be performed at a timing within a time from the start of the upper/lower mold opening step 62A1 for opening upper and lower molds in the injection molding process 62A to release a preform 3P to the completion of the injection mold high-pressure switching step 62A3 for increasing the mold clamping force for the closed injection molding mold.
a) of the preform body portion (14) is a mirror-finished surface (20), and the outer surface of the injection core mold for forming the preform other than the mirror-finished surface is a roughened surface (15).
When a hollow molded body using a preform to be molded with a thin bottom portion is produced while taking advantage of the roughening of the outer surface of an injection core mold, transferred roughening marks are prevented from appearing on the bottom portion of hollow molded bodies, so that the hollow molded body with an aesthetic bottom portion is obtained. An injection core mold (12) has an outer surface of its tip portion corresponding to a preform bottom portion (10) and a lower end portion (14a) of a preform body portion (14) . The outer surface corresponding to the preform bottom portion (10) and the lower end portion (14a) of the preform body portion (14) is a mirror-finished surface (20) , and the outer surface of the injection core mold for forming the preform other than the mirror-finished surface is a roughened surface (15) .
An injection apparatus is configured to feed a molten resin into an injection molding section of an injection stretch blow molding machine. The injection apparatus uniformly melts a resin material while the duration from the time of starting plasticizing and kneading till completion of injection is shortened, thereby allowing the operation of the injection apparatus to fall within the time corresponding to the reduced injection molding process in the injection stretch blow molding machine. Thus, the molding cycle for a hollow body is reduced. In this context, at the start of the filling for each injection cycle, the injection apparatus starts plasticizing and kneading for generating the molten resin for injection in the next injection cycle.
An object is to provide an injection stretch blow molding machine and a method for molding a polyethylene container capable of molding a favorable hollow container even if its preform is released from an injection mold early. The injection stretch blow molding machine and the method for molding a polyethylene container molds a preform by injecting and filling a molten polyethylene resin into an injection mold, which includes a cavity mold and a core mold both cooled to a temperature range of 5° C. to 25° C., transfers the molded preform to a blow molding mold, and molds a hollow container by blowing the preform within a time range of ±2 sec from a point in time when a temperature of the preform reaches a first minimum point after a point in time when the injection mold completes being opened.
An object is to provide an injection stretch blow molding machine and a method for molding a polyethylene container capable of molding a favorable hollow container even if its preform is released from an injection mold early. The injection stretch blow molding machine and the method for molding a polyethylene container molds a preform by injecting and filling a molten polyethylene resin into an injection mold, which includes a cavity mold and a core mold both cooled to a temperature range of 5 C to 25 C, transfers the molded preform to a blow molding mold, and molds a hollow container by blowing the preform within a time range of 2 sec from a point in time when a temperature of the preform reaches a first minimum point after a point in time when the injection mold completes being opened.
An injection apparatus is configured to feed a molten resin into an inj ection molding section of an inj ection stretch blowmolding machine. The injection apparatus uniformly melts a resin material while the duration fromthe time of startingplasticizing and kneading till completion of injection is shortened, thereby allowing the operation of the injection apparatus to fall within the time corresponding to the reduced injection molding process in the injection stretch blow molding machine. Thus, the molding cycle for a hollow body is reduced. In this context, at the start of the filling for each injection cycle, the injection apparatus starts plasticizing and kneading for generating the molten resin for injection in the next injection cycle.
When a preform is released at an early stage from an injection molding mold, the injection cooling time is shortened before releasing the preform at an early stage from the injection molding mold to shorten the cycle time of molding the preform while the preform trunk portion is prevented from being deformed. A trunk support portion is formed on an outer end inner surface portion of a support ring molding portion in the lip mold and is configured to support a preform trunk portion at a time of releasing the preform in a non-contact manner.
According to the present invention, while a molten resin can be fed from a hot-runner device such that a high-temperature and low-viscosity resin is not unevenly distributed, a preform in which the high-temperature and low-viscosity resin is not unevenly distributed in the circumferential direction is injection molded into a preform molding portion of an injection molding mold. An introduction runner portion 18 of a hot-runner device 9 is bent toward a transverse runner portion 15 after reaching a vertical plane A that passes through the position of the transverse runner portion 15 in the vertical direction, and the introduction runner portion 18 is connected, in the vertical plane A, to a portion midway along the transverse runner portion 15.
An aim of the present invention is to enable a molten resin to be fed from a hot runner apparatus into preform molding portions of an injection molding mold without a higher temperature and lower viscosity resin being present in a biased manner and to enable preforms having no biased portion of a higher temperature and lower viscosity resin in their circumferential direction.An introducing runner portion (18) of a hot runner apparatus (9) is bent toward a horizontal runner portion (15) after reaching an elevation plane (A) passing through a position of the horizontal runner portion (15) in an up-and-down direction and continuous with an intermediate portion of the horizontal runner portion (15) in the elevation plane (A) .
Fixation of a container shape of a hollow molded body is not completed during a blow molding process but is completed during an ejection process of an ejection section, thereby shortening an operation time in a stretch blow molding section, and improving the production efficiency of hollow molded bodies by shortening the time required for the blow molding process during a molding cycle.
Cooling air is blown into the inside of the hollow molded body disposed in the ejection section in the ejection process C during the blow molding process B in the next molding cycle to cool the hollow molded body disposed in the ejection section to solidify the container shape.
In the present invention, a hollow molded body is manufactured with an injection stretch blow molding machine for which the molding cycle has been shortened, and energy is saved in the manufacturing of the hollow molded body. A blowing device (10) of a stretch blow molding device (11) includes: a compressed air supply source (32) for feeding compressed air at an air pressure that expands a shaping target (e) and shapes the target into the shape of a hollow molded body; an inflow passage (33) where the compressed air flows from the compressed air supply source into an inner space of the shaping target disposed inside a blow mold (8); and a non-closed outflow passage (34) where the compressed air flows out from the inner space into an exhaust space outside the blow mold. In all steps of the blow operation by the blowing device, a compressed air flow passage (36) is formed where the compressed air flows from the compressed air supply source, through the inflow passage and the inner space, and from the outflow passage to the exhaust space, and throughout all steps of the blow operation, the shaping and the cooling are performed simultaneously by blowing in the compressed air that was set at an air pressure to expand the shaping target, which is in a preform shape, and to shape the shaping target into a hollow molded body.
When an injection stretch blow molding machine in which the molding cycle is tried to be shortened manufactures hollow molded bodies, blow molding in which shaping and cooling are simultaneously performed by blowing compressed air from a single compressed air supply source while discharging compressed air is performed to achieve energy saving for manufacturing hollow molded bodies.A blowing apparatus 10 of a stretch blow molding apparatus 11 includes a compressed air supply source 32 configured to send out compressed air adjusted to have an air pressure at which an object to be shaped e is inflated to be shaped into a hollow molded body, an inflow passage 33 through which the compressed air from the compressed air supply source 32 flows to the internal space of the object to be shaped e disposed in a blow mold 8, and a non-closed outflow passage 34 through which the compressed air flows out from the internal space of the object to be shaped e to a discharging space outside the blow mold. In the entire process of the blowing operation by the blowing apparatus 10, a compressed air flow passage 36 is formed through which the compressed air from the compressed air supply source 32 flows through the inflow passage 33 and the internal space of the object to be shaped e and through the outflow passage 34 into the discharging space. Shaping and cooling are simultaneously performed by blowing49the compressed air adjusted to have an air pressure at which the object to be shaped e being in the form of a preform is inflated to be shaped into the hollow molded body throughout the entire process of the blowing operation.
The purpose of the present invention is to manufacture a hollow molded body in which whitening does not occur in a gate part and which is free from stringiness in such a manner that a preform capable of being blow-molded is properly divided between a resin portion of the gate part and a resin portion on a heat insulation sheet side of the preform to allow mold release by a preform molding device in which a disc-shaped heat insulation sheet having a simple shape is held between a circular-hole-shaped concave part on a cavity mold side and a tip end of a hot runner nozzle that is inserted into the circular-hole-shaped concave part. The thickness of a heat insulation sheet 13 is set at a thickness at which a resin melting layer 20 and a resin heat insulation layer 21 are formed in an opening 16 of the heat insulation sheet 13, and the circular opening of the opening 16 is set at a width at which a resin in the resin heat insulation layer 21 that performs heat exchange with the resin melting layer 20 is allowed to come in contact with an inter-concave part top surface 10 of a circular-hole-shaped concave part 6 of a cavity mold 5 and perform heat exchange to maintain a solidified state.
The purpose of the present invention is to improve the manufacturing efficiency of a hollow molded body through a reduction of the time required for a blow molding step in a molding cycle by making fixation of the container shape of the hollow molded body completed not during the blow molding step but during an ejection step in an extraction section, thereby shortening the operation time in a stretch blow molding section. The inside of the hollow molded body arranged in the extraction section in the ejection step C is sprayed with cooling air during the blow molding step B in a next molding cycle, thereby cooling the hollow molded body arranged in the extraction section and completing fixation of the container shape.
The purpose of the present invention is to improve the manufacturing efficiency of a hollow molded body through a reduction of the time required for a blow molding step in a molding cycle by making fixation of the container shape of the hollow molded body completed not during the blow molding step but during an ejection step in an extraction section, thereby shortening the operation time in a stretch blow molding section. The inside of the hollow molded body arranged in the extraction section in the ejection step C is sprayed with cooling air during the blow molding step B in a next molding cycle, thereby cooling the hollow molded body arranged in the extraction section and completing fixation of the container shape.
A plastic bottle is provided with a mouth, a main unit, for example, a flexible, cylindrical main unit, connecting the interior of the bottle with the mouth, a base structured to close the bottom portion of the main unit and have a greater rigidity compared to the main unit. The main unit includes a lower body section extending upward from the base, a central body section extending upward from the lower body section, and a crease between the lower and central body sections. The central body section can be configured to deform into a substantially flat shape through the action of external force F so as to bend outward.
B65D 81/32 - Containers, packaging elements, or packages, for contents presenting particular transport or storage problems, or adapted to be used for non-packaging purposes after removal of contents for packaging two or more different materials which must be maintained separate prior to use in admixture
B65D 35/28 - Pliable tubular containers adapted to be permanently deformed to expel contents, e.g. collapsible tubes for toothpaste or other plastic or semi-liquid materialHolders therefor with auxiliary devices for expelling contents
plastics moulding and processing machines, plastic stretch blow moulding machines, injection, extrusion, blow, compression and vacuum moulding machines, and parts therefor; metal working machines
(1) Plastic moulding and processing machines, injecting stretch-blow moulder, injection, extrusion, blow, compression and vacuum moulding machines, their parts and fittings; metal working machinery and implements.
