Abstract: According to the present invention, in order to improve the productivity of an injection stretch blow molding machine, when a core mold is lifted during mold opening at an injection molding part of the injection stretch blow molding machine, stress is dispersed so as not to concentrate at an area where the thickness changes between a preform opening and a preform body so that the preform body is inhibited from being lifted at a skin layer formed in the area where the thickness changes between the preform opening and the preform body.

Abstract: A preform having an inverted truncated conical bottom section is used. The inclined inner surface of a bottle bottom surface-forming portion of the bottom section is formed into a gently curved convex surface that extends from the lower portion of a bottle bottom edge-forming portion of the bottom section to a curved portion in the lower portion of the bottom section so that the thickness of the bottle bottom surface-forming portion is greater than the thickness of the barrel section of the preform and the thickness of the bottle bottom edge-forming portion. The increase in thickness of the bottom section improves the efficiency of stretching the bottom section, and the circumferential wall of the bottom section can thereby be efficiently stretched. This allows a reduction in weight (thickness) of the bottom surface section of a stretch blow molded bottle, and a reduction in weight of the bottle is thereby achieved.

Abstract: An injection/stretch blow mold clamping mechanism comprises mold clamping shafts erected vertically movably on both sides of an injection molding operation section and extending through the lower base platen and upper base platen, hydraulic mold clamping means connected respectively to lower ends positioned within a bed of the clamping shafts, a mold clamping platen having core molds attached thereto and being fitted on the mold clamping shafts, the clamping platen being installed vertically movably between the upper base platen and a top platen, a pair of mold air cylinders connecting on both sides thereof the upper base platen and the clamping platen with each other and causing the clamping platen to move vertically with respect to the upper base platen, a mold clamping rod connected to the mold clamping platen through the top platen, and a pair of clamp members disposed on an upper surface of the top platen.

Abstract: In the hot parison method of stretch blow molding, the temperature distribution of the body wall of the injection molded preform is changed to a gentle gradient slope shape from a mountain shape not by the external application of heat, but by the preform itself, to prepare a bottle with an improved top load value. After the injection-molded preform is released from the mold, cooling of the inner side of the preform is continued by the injection core. Inner side cooling is terminated by release from the injection core. The preform is left in a hollow state for a time, the temperature-averaging time, until the outer surface temperature drops to the stretch blow molding temperature, after passing a peak temperature. While in the molding temperature region, stretch blow molding of the thin-wall hollow molded article is conducted.

Abstract: A preform of injection-molded PET has a body wall thickness of 3.0-4.5 mm. The preform is high-temperature mold-released from an injection cavity mold and an injection core. Pre-blowing of the preform is restricted at 5±0.5 seconds after the mold release, at a temperature of 112-117° C. of the pre-blow mold, and for a pre-blowing time of 0.5-1.0 second. Air blowing is applied to expand only the body of the preform. Stretch blow molding is performed restrictively at 3-4 seconds after the mold release from the pre-blow mold, at a temperature of 103-107° C. of the blow mold, and for an air blowing time of 6-9 seconds, thereby stretch blow molding the preform into a bottle and simultaneously heat setting to impart heat resistance to the bottle.

Abstract: Provided is an injection/stretch blow molding machine, which performs both injection molding of a preform and stretch blow molding of a hollow molded product continuously within single machine.

Abstract: A preform of injection-molded PET has a body wall thickness of 3.0-4.5 mm. The preform is high-temperature mold-released from an injection cavity mold and an injection core. Pre-blowing of the preform is restricted at 5±0.5 seconds after the mold release, at a temperature of 112-117° C. of the pre-blow mold, and for a pre-blowing time of 0.5-1.0 second. Air blowing is applied to expand only the body of the preform. Stretch blow molding is performed restrictively at 3-4 seconds after the mold release from the pre-blow mold, at a temperature of 103-107° C. of the blow mold, and for an air blowing time of 6-9 seconds, thereby stretch blow molding the preform into a bottle and simultaneously heat setting to impart heat resistance to the bottle.

Abstract: A tube-like plastic container and a preform therefor are provided. The preform has a drum part and a mouth part, with a continued portion having a projecting edge in between. The drum part is thicker than the mouth part, has a flat wedge-like form, and tapers toward a thinner bottom end. The drum part is thicker at a lower portion than at an upper portion.

Abstract: To solve the limit of wall-thickness adjustment of a preform for a small flat container by a flat core by forming the outer side of a step-up-formed large-wall-thickness shell part with reducing wall thickness. A preform 1 for a small flat container whose inside diameter is completely circular and restricted to a small value is used. A shell part 12 is step-out-formed from the boundary between a neck part 11 and a shell part 12 so that the shell part 12 has a diameter larger than the neck part 11. A difference is provided between wall thickness of forward/backward sides 12a and right/left sides 12b of the shell part 12 by forming the outer side of the shell part into an ellipse form or the like from the underside of step-out at with reducing wall thickness. A stepped out part 14 is left like a disk in the underside of the neck part.

Abstract: Improvement of simplicity and durability of a stretch rod extending device and a bottom mold lifting device, equipped on a stretch blow molding machine, is achieved by applying a combination of a magnetic screw shaft and a magnetic nut member, which is able to convert rotary-linear movement smoothly without contact. The nut member and the screw shaft of the extending device 6 and lifting device 30 comprise a magnetic nut member 65, 116 and a magnetic screw shaft 66, 117, having spiral N magnetic pole and S magnetic pole alternately provided on inner peripheral surface of a cylindrical member and outer peripheral surface of a shaft at a same regular pitch. The magnetic screw shaft is inserted into the plunger 61, 115, having the magnetic nut member equipped inside with keeping required clearance so as to match the magnetic pole to oppose the magnetic nut member at the same poles each other.

Abstract: The present invention relates to a mold device having a combination of molds for stretch blow molding, comprising a main blow mold 5, installed on a pair of platens 2 by being separated into split molds 5a, a pre-blow mold 10, attached to a lifting device 11 under the area between the split molds 5a, and movable in and out from the area between the split mold 5a, a neck mold 7, which is fitted into the pre-blow mold 10 and main blow mold 5 respectively, a blow core 20, which is fitted in to the neck mold 7, and a stretch rod. The pre-blow mold 10 comprises a cylindrical member having an open end on the upper portion, which is fitted into the neck mold 7. A bottom mold 8 of the main blow mold 5 is installed in the bottom portion of the split mold 5a by being separated into split bottom molds 8a. Lifting cylinders 9 are placed under the both of the split bottom molds 8a in order to make the bottom mold 8 movable in and out from the bottom portion of a cavity.

Abstract: The present invention provides a blow molding machine comprising a plurality of pillars 5 set up facing on a seat 4 above a base 3 located above a blow mold 2; a stationary platen 6 provided bridging on the top portions of the pillars 5; a moving cylinder 7 set on both side of the stationary platen 6; and a holding plate 9 of blow-core members, which is connected with a piston rod 7a of the moving cylinder 7, and in which the pillars 5 are inserted vertically movable; and a clamp plate 15 projecting at both ends from the holding plate 9 outwardly, and a clamp block 16, which includes internally a pair of hydraulic cylinders 18 to clamp the clamp plate 15 from both sides with rams when the holding plate 9 is in the lower limit position, which is provided on both sides of the seat 4.

Abstract: The shifting of the parting line between split molds due to mold clamping force is prevented. A blow mold device (11) wherein a pair of split molds forming a blow cavity (12) are a set of molds, and a plurality of such sets are attached in parallel to mold-attaching plates (15, 16) with a clearance defined between adjacent sets. One split mold (13) is attached by bolts (17) inserted in bolt holes (23) in the form of loose holes in the mold-attaching plate (15) in such a manner as to allow relative lateral shifting of the split mold (13) and mold-attaching plate (15). The other split mold (14) is fixedly attached to the mold-attaching plate (16) by locating pins (18) and bolts (17). A joint is installed that integrally connects the two split molds to their parting surface and that is composed of a taper pin (19) and a socket (21) for preventing the shifting of the parting line.

Abstract: An injection blow molding device in which a lip mold is formed in different shapes for an injection mold and a blow mold. Mold clamping surfaces corresponding to the different shapes are formed on the injection mold and the blow mold, respectively, to prevent an air leakage from the blow mold. An upper portion of an outside surface of the lip mold which contacts the mold is formed in a tapered surface whereas a lower end portion of the outside surface is formed in a vertical surface. The upper portion and the lower portion of a surface contacting the lip mold, of each of the injection mold and the blow mold are formed respectively in a tapered surface and a vertical surface that correspond to the tapered surface and the vertical surface of the outside surface of the lip mold. Clamping the lip mold in the injection mold is performed at the tapered surface of the upper portion and clamping the lip mold in the blow mold is performed at the vertical surface of the lower end portion.

Abstract: The mold opening speed is increase by upward moving a movable plate of a vertical clamping device for an injection blow molding machine by hydraulic cylinders at the both sides instead of a booster ram. The following are used: a lower base plate with an injection cavity mold set on its upper surface, a cylinder block for clamping connected to upper ends of tie bars vertically disposed at both sides of the lower base plate, an upper base plate vertically movably set above the lower base plate guided by the tie bars to rotatably hold a turntable of a neck mold below the upper base plate, a movable plate vertically movably set on the upper base plate guided by the tie bars and connected with a clamping ram at the center of the upper surface, and an injection core inserted into a cavity of an injection cavity mold through the upper base plate, turntable, and neck mold and attached to the under face of the movable plate.

Abstract: To realize direct and intermittent rotation of a transfer member by directly coupling the rotary part of a servo motor with a rotary shaft. A supporting board is arranged side by side with working space 3 made vacant above a machine base. The center part of a transfer member arranged on the undersurface of a supporting board 4 is coupled with a rotary shaft 7 of a relatively large diameter inserted through the center of the supporting board and mounted on a bearing. The servo motor 8 provided with the fixing part 8b inside of the rotary part 8a of the large diameter in the center of the supporting board 4 is attached to a supporting base 15 erected on the supporting board 4 via a joint 18 on the side of the fixing part 8b. The rotary part 8a is mounted on the top of the rotary shaft 7, and thereby the transfer member 6 is constructed so as to be directly rotated with the rotary shaft 7 by the servo motor 8.

Abstract: Improve the strength of the stretch blow receptacle and make the heat resistant treatment easier, by making the receptacle wall cross-section multi-layered in view of crystalline density, and the crystalline density of the surface layer high density. The inventions concerns a thin plastic receptacle 2 molded by stretch blowing of a bottomed preform 1 in the longitudinal and transversal directions. The wall cross-section is composed of inside and outside surface layers 2a whose crystalline density is high by stretching, a core layer 2b presenting a lower density than the surface layers 2a, and an intermediate layer 2c presenting a graduated density between both layers 2a, 2b.

Abstract: The present invention relates to an injection stretch blow molding method of forming a cylindrical narrow mouth container comprising the following steps; injection molding a preform having a body portion integrally molded with a neck portion wherein the body is formed thicker-wall and larger outside diameter than the neck portion from a closing surface between a neck mold and an injection cavity mold, and having a step-out portion, wherein an upper surface of the step-out portion is formed by the closing surface of the neck mold between the neck portion and the body portion and the step-out portion has a smaller outside diameter than the body of the container, and stretch blow molding the preform to the container in a blow cavity mold, wherein a body portion of the container is formed thin-wall from around the upper surface of the step-out portion, and the step-out portion and an expanded portion around the upper surface of the step-out portion form a shoulder portion of the container flat, and also the outsi

Abstract: A method for stretch blow molding a wide-mouthed container, employing a preliminary stretching before stretch blowing without making an upper body portion thickened so as to thin the wall thickness from the connecting portion between the mouth portion and the body portion, thereby preventing the thickening phenomenon at the subjected portion. A preform having a large diameter mouth portion, a body portion and a bottom portion is injection molded within an injection mold. The preform is released from the injection mold in a state where the inside thereof is still in a high temperature while holding the mouth portion of the preform with a lip mold. Then, the preform is transferred to a blow mold as it is. Before the stretch blow molding step of the preform, a stretching rod is descended in a predetermined length to preliminary stretch the body portion in some extent.

Abstract: A required preform 2 is molded by rapidly cooling molten resin which has been injected and filled into an injection mold. The preform 2 is held by its neck portion with a neck mold and is mold-released in a high temperature state. A bottle 1 having a thin body portion 1a is molded by stretch blowing laterally and longitudinally within a blow mold. Among the thickness 2a and length 2b of a stretched portion of the preform 2 which are set according to the volume and weight and body portion thickness 1a of the bottle 1, the thickness 2a is set to be thinner than the usually set thickness. The length 2b is set to be long inversely proportional to the thickness setting. The preform 2 is mold-released at a higher temperature than usual and is stretch-blow molded before its outer surface temperature reaches its peak.