JP2006035667A - Injection blow molding machine and injection blow molding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To mold a preform having a proper temperature distribution corresponding to the material or shape of the preform or the shape or the like of a molded product obtained by blow molding by changing a temperature at every region of the preform when the preform molded in an injection station is cooled and to dispense with a heating station. <P>SOLUTION: This injection blow molding machine 10 is equipped with an injection mold support device to which a fixed mold 13 is attached, a blow mold support device to which a movable mold is attached, an injection core mold 42 and a blowing guide 43 and has the intermediate mold support device arranged between the injection mold support device and the blow mold support device and is constituted so as to subject an intermediate molded product molded by injection molding to blow molding to mold a final molded product. The fixed mold 13 and/or the injection core mold 42 is equipped with a cooler for adjusting the temperature distribution of the intermediate molded product corresponding to blow molding. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to an injection blow molding machine and method.

  2. Description of the Related Art Conventionally, in a molding machine that molds a test tube preform by injection molding, the molding efficiency is improved by controlling the temperature of the molded preform (see, for example, Patent Document 1).

Further, there is provided an injection blow molding machine capable of performing a step of forming a test tubular preform by injection molding and a step of blow molding the preform, that is, a step of blow molding, with a single molding machine. . In this case, when injection molding is performed in a state where the mold is closed at the injection station to form a test tubular preform, the preform is loaded into a female mold for blow molding, and the mold is closed. Blow molding is performed. Therefore, injection molding and blow molding can be performed simultaneously at the injection station and the blow station in a single molding machine, and the throughput of the molded product is improved. Moreover, since injection molding and blow molding are performed by a single molding machine, the entire molding machine becomes compact and installation space can be saved.
JP 2000-351151 A

  However, in the conventional injection blow molding machine, since the temperature distribution of the preform molded by injection molding is not suitable for blow molding, a heating station is arranged between the injection station and the blow station. The preform thus formed is heated at a heating station and then moved to a blow station to perform blow molding. Therefore, it is necessary to provide a heating station, the structure of the injection blow molding machine becomes complicated, the apparatus becomes large, and the cost increases. Moreover, it takes time to heat the preform at the heating station, and the time required for the molding cycle becomes long.

  However, it is also conceivable that the temperature distribution of the preform is made suitable for blow molding by appropriately controlling the temperature when the preform molded at the injection station is cooled, and the heating station is omitted. However, in blow molding, the temperature distribution of the preform is required to be strictly controlled in accordance with the shape of the preform, the shape of the molded product obtained by blow molding, and the like. Depending on the temperature control of the preform in the molding machine, a temperature distribution suitable for blow molding could not be obtained.

  In addition, the thickness of the blow molded product is measured, the preform mold is corrected based on the measurement result, and the thickness distribution in the blow molding is corrected.

  However, there are problems such as an increase in cost for correcting the mold and a long time required for the correction, resulting in poor productivity.

  The present invention solves the problems of the conventional injection blow molding machine so that the temperature can be changed for each part of the preform when the preform molded at the injection station is cooled. An injection blow molding machine and method that can form a preform having an appropriate temperature distribution corresponding to the shape and shape of a preform, the shape of a molded product obtained by blow molding, etc., and does not require a heating station The purpose is to provide.

  Therefore, the injection blow molding machine of the present invention comprises an injection mold support device to which a fixed mold is attached, a blow mold support device to which a movable mold is attached, an injection core mold and a blow guide, An intermediate mold support device disposed between the injection mold support device and the blow mold support device, and blow molding is performed on an intermediate molded product formed by injection molding to form a final molded product In the injection blow molding machine, the fixed mold and / or the injection core mold includes a cooling device that adjusts the temperature distribution of the intermediate molded product corresponding to the blow molding.

  In another injection blow molding machine of the present invention, the cooling device can change a cooling capacity in accordance with a portion of the intermediate molded product.

  In still another injection blow molding machine of the present invention, the cooling device further changes a flow rate of the cooling medium.

  In still another injection blow molding machine of the present invention, the cooling device further circulates cooling media having different temperatures.

  In still another injection blow molding machine of the present invention, the cooling device for the fixed mold further includes a plurality of cooling means, and adjusts the surface temperature of the intermediate molded product.

  The injection blow molding method of the present invention is an injection blow molding method by a molding machine that performs blow molding on an intermediate molded product molded by injection molding to form a final molded product, wherein the temperature distribution of the intermediate molded product is determined. Adjust according to blow molding.

  In another injection blow molding method of the present invention, the temperature distribution is further adjusted by changing the cooling capacity in accordance with the portion of the intermediate molded product.

  In still another injection blow molding method of the present invention, the cooling capacity is further changed by changing the flow rate of the cooling medium.

  In still another injection blow molding method of the present invention, the cooling capacity is further changed by circulating cooling media having different temperatures.

  The mold of the injection blow molding machine of the present invention is a mold of an injection blow molding machine, and includes a male mold part that includes an internal space part and forms an inner peripheral part of a preform, and the male mold part. An inner tube member to be inserted into the inner space, an inside of the inner tube member, and a refrigerant flow path formed between the outer periphery of the inner tube member and the inner periphery of the male part, A pipe member is provided with the uneven part formed in the perimeter.

  In the mold of another injection blow molding machine of the present invention, the uneven portion further changes in the longitudinal direction of the inner tube member.

  In still another injection blow molding machine of the present invention, the uneven portion is formed in consideration of the shape of the final molded product.

  According to the present invention, an injection blow molding machine comprises an injection mold support device to which a fixed mold is attached, a blow mold support device to which a movable mold is attached, an injection core mold and a blow guide, An intermediate mold support device disposed between the injection mold support device and the blow mold support device, and blow molding is performed on the intermediate molded product formed by injection molding to form a final molded product. In the injection blow molding machine, the fixed mold and / or the injection core mold includes a cooling device that adjusts the temperature distribution of the intermediate molded product corresponding to the blow molding.

  Therefore, it is possible to form an intermediate molded product having an appropriate temperature distribution corresponding to the material and shape of the intermediate molded product, the shape of the final molded product obtained by blow molding, and the like, and no heating station is required.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a partial plan sectional view of an injection blow molding machine according to an embodiment of the present invention, and FIG. 2 is a front partial sectional view of the injection blow molding machine according to the embodiment of the present invention, showing a state where the mold is closed. .

  In the figure, reference numeral 10 denotes an injection blow molding machine, a fixed platen 11 as an injection mold support device fixed to a support frame 18, and a blow mold support slidably attached to a guide member 18 a on the support frame 18. A movable platen 12 as an apparatus, and an intermediate mold support frame 21 as an intermediate mold support device slidably attached to a guide member 18a on the support frame 18 between the fixed platen 11 and the movable platen 12. Have. The injection blow molding machine 10 forms a preform 61, which will be described later, as a test tubular intermediate molded product by injection molding, and a final molded product, which will be described later by blow molding, that is, blow molding. The apparatus which performs the process shape | molded in 62. In the injection blow molding machine 10, injection molding is performed at the injection station between the fixed platen 11 and the intermediate mold support frame 21, and the blow is performed at the blow station between the movable platen 12 and the intermediate mold support frame 21. Molding is performed. It is also possible to use a blowing station between the fixed platen 11 and the intermediate mold support frame 21 and an injection station between the movable platen 12 and the intermediate mold support frame 21. The final molded product 62 may have any shape. Here, the final molded product 62 is a bottle-shaped or bottle-shaped bottomed container having a narrow-diameter open mouth, A description will be given assuming that a male screw is formed on the outer periphery.

  A fixed mold 13 as an injection mold is attached to the mold mounting surface (the left surface in FIGS. 1 and 2) of the fixed platen 11. An injection core mold 42 is disposed on the surface of the core mold frame 41 as an intermediate mold that is non-rotatably attached to the intermediate mold support frame 21 on the fixed platen 11 side. The injection core mold 42 includes a root portion 42a and a male mold portion 42b. When the fixed mold 13 and the injection core mold 42 are in close contact with each other and the mold is closed, the injection core mold 42 is interposed between the fixed mold 13 and the fixed mold 13. A cavity having the shape of the preform 61 is formed. 1 shows a state in which the fixed mold 13 and the injection core mold 42 are opened and the mold is opened, and FIG. 2 shows a state in which the mold is closed.

  An injection device (not shown) is disposed on the back surface (right surface in FIG. 2) of the fixed platen 11. Here, the injection apparatus includes a heating cylinder, and a raw material hopper for charging a raw material resin such as resin pellets into the heating cylinder is attached to the heating cylinder. Further, a screw is disposed in the heating cylinder so as to be able to rotate and to advance and retreat. An injection driving device for rotating the screw in the heating cylinder and moving it forward or backward is disposed behind the heating cylinder.

  In the metering step, the screw is driven to rotate, the screw is rotated, and the resin is accumulated in the front of the screw, whereby the screw is retracted to a predetermined position. At this time, the raw material resin supplied from the raw material hopper is heated and melted in the heating cylinder, and the screw is moved backward by the pressure of the resin stored in front of the screw. Subsequently, in the injection process, the nozzle at the tip of the heating cylinder is pressed against the fixed mold 13 and the injection driving device is driven to advance the screw. As a result, the resin stored in front of the screw is injected from the tip of the nozzle and filled into a cavity formed between the fixed mold 13 and the injection core mold 42.

  Further, a blow mold for blow molding, that is, a movable split mold 14 as a movable mold is attached to the mold mounting surface (the right side surface in FIGS. 1 and 2) of the movable platen 12. The movable split mold 14 includes a drive-side movable part 14a, a driven-side movable part 14b, and a fixed bottom part 14c, and the drive-side movable part 14a and the driven-side movable part are separated by a split-type drive cylinder device 17 as a split-type drive apparatus. 14b is moved in the horizontal direction (vertical direction in FIG. 1). In this case, the drive-side movable portion 14a is connected to the piston rod 17a of the split-type drive cylinder device 17, and is directly moved by the split-type drive cylinder device 17, and the driven-side movable portion 14b is another set of drives. It is connected to the side movable part 14a and is moved in a direction facing the drive side movable part 14a of its own set. A blowing guide 43 is disposed on the surface of the core mold 41 attached to the intermediate mold support frame 21 on the movable platen 12 side. The blowing guide 43 includes a root portion 43a, and is in close contact with an inlet of a blow molding female mold, which will be described later, formed in close contact with the drive side movable portion 14a and the driven side movable portion 14b. In FIG. 5, a blow molding space having the shape of the final molded product 62 is formed. FIG. 1 shows a state where the drive side movable portion 14a and the driven side movable portion 14b of the movable split mold 14 are opened, and the movable split mold 14 and the blowing guide 43 are opened and the mold is opened. FIG. 2 shows a closed state.

  A mold clamping device (not shown) is disposed on the back surface (left surface in FIG. 2) of the movable platen 12. The mold clamping device includes a mold clamping cylinder device for driving the movable platen 12 and a support plate to which the mold clamping cylinder device is attached. The fixed platen 11 and the support plate are connected by a plurality of, for example, four tie bars 15, and the movable platen 12 and the intermediate mold support frame 21 move forward or backward along the tie bar 15 (in FIGS. 1 and 2). (Move rightward or leftward). The fixed platen 11 is fixed to the support frame 18 by a fixing member such as a bolt. The movable platen 12 and the intermediate mold support frame 21 are supported and slid mainly by the guide member 18a from below.

  In the present embodiment, the mold clamping device and the drive source of the mold clamping device may be of any type, and instead of the mold clamping cylinder device, a toggle mechanism type using a toggle link is used. Alternatively, a composite system in which a link mechanism and a cylinder device are combined may be used. Also, the drive source may be a hydraulic cylinder device, or a combination of an electric motor and a ball screw.

  Further, an intermediate drive cylinder device 22 as an intermediate drive device is attached to the fixed platen 11, and an intermediate support frame 21 is attached to a connecting rod 23 connected to the piston rod of the intermediate drive cylinder device 22. ing. Then, by operating the intermediate drive cylinder device 22, the intermediate support frame 21 can be moved forward or backward with respect to the fixed platen 11. Thereby, the intermediate mold support frame 21 can be moved with respect to the stationary platen 11, and the injection molding and blow molding are performed by performing mold closing, mold clamping, and mold opening at separate timings at the injection station and the blowing station. It can be carried out.

  In the present embodiment, the intermediate support frame 21 has a substantially gate shape, and a lower end portion is slidably attached to the guide member 18a, and the left and right leg portions extending in the vertical direction, and the leg portions. And a top plate portion extending in the lateral direction for connecting the upper end portions. The core mold 41 is disposed between the left and right legs. Here, the core mold 41 is fixed to a cylindrical support column 47 attached through the left and right legs. That is, the core mold 41 is non-rotatably attached to the intermediate mold support frame 21.

  A rotating frame 31 as a gripping frame is rotatably attached to the left and right outer sides of the intermediate support frame 21 in the support column 47. In the state shown in FIGS. 1 and 2, columnar guide bars 33 extending forward and rearward are attached to the front and rear sides (right and left sides in FIGS. 1 and 2) of the rotary frame 31. Yes. Although the number of the guide bars 33 can be set arbitrarily, in the example shown in the drawing, two guide bars 33 are attached to the left and right rotating frames 31 in the front-rear direction. A grip frame 32 that supports a molded product gripping device 52 for gripping the outer periphery of the mouth of the preform 61 as an intermediate molded product is slidable on the guide bar 33 in the axial direction of the guide bar 33. And it is attached to the front-end | tip part 33a of the guide bar 33 so that it can lock and open | release. In the state shown in FIG. 1, the grip frame 32 is locked to the distal end portion 33 a of the guide bar 33 by the grip frame engaging portion 32 a and does not slide in the axial direction of the guide bar 33. Note that when the engagement between the gripping frame engaging portion 32 a and the tip end portion 33 a is released, the gripping frame 32 is released and can slide in the axial direction of the guide bar 33.

  The grip frame engaging portion 32a is releasably engaged with the tip end portion of the injection side engaging / disengaging member attached to the fixed platen 11, and is operated by the tip end portion of the injection side engaging / disengaging member, so that the guide bar 33 is engaged with or disengaged from the tip 33a. Further, the grip frame engaging portion 32a is releasably engaged with the tip of the blowing side engaging / disengaging member attached to the movable platen 12, and is operated by the tip of the blowing side engaging / disengaging member. The tip 33a of the guide bar 33 is engaged or disengaged.

  An electric motor 34 is attached to one leg portion of the intermediate support frame 21 as a drive source for rotating the rotary frame 31. Then, by operating the electric motor 34, the rotary frame 31 rotates around the support column 47.

  On the upper outer surface and lower outer surface of the core mold 41, grip release as a drive source for driving a grip release member (not shown) for operating the molded product gripping device 52 to release the grip state Each drive device 45 is attached. The grip release driving device 45 may be a hydraulic cylinder device or a combination of an electric motor and a ball screw. Here, it is a pneumatic cylinder device, and the pneumatic cylinder A description will be given assuming that the grip release member is attached to the piston rod of the apparatus. When the grip release driving device 45 is actuated, the grip release member is advanced and retracted.

  By the way, the extending rod 44 is attached to the blowing guide 43 so as to protrude from the root portion 43a. And on the outer surface on the upper side and the lower outer surface of the core mold 41, there are respectively a stretching rod driving device 46 as a driving source for operating the stretching rod 44 to protrude from the root portion 43a. Is attached. The drawing rod drive device 46 may be a hydraulic cylinder device or a combination of an electric motor and a ball screw, but here, it will be described as a pneumatic cylinder device. When the drawing rod driving device 46 is operated, the connecting plate 46a connected to the piston rod of the drawing rod driving device 46 moves, and the drawing rod 44 having the root portion attached to the connecting plate 46a is moved. It protrudes and the said preform 61 is extended. That is, in the present embodiment, the stretch rod 44 protrudes into the preform 61, and the preform 61 is finally blown by stretch blow molding in which high pressure air is blown while the preform 61 is stretched. The molded product 62 is molded. In this case, a blowing guide 43, an extending rod 44, or an air flow path (not shown) for supplying high pressure air for blow molding, an air ejection hole (cutting), and the like are formed between them.

  If necessary, the preform 61 can be formed into the final molded product 62 by blow molding in which high-pressure air is blown without projecting the stretching rod 44. In this case, the stretching rod 44, the stretching rod driving device 46, etc. can be omitted. It should be noted that power is supplied to piping for supplying high-pressure air as working fluid to the grip-release driving device 45 and the stretching rod driving device 46, piping for supplying high-pressure air for blow molding, and various devices. A signal line or the like for transmitting a signal from an electric wire, a sensor, or the like can be disposed so as to pass through the hollow support column 47.

  The injection blow molding machine 10 has a control device (not shown). The control device includes operations of the injection device, mold clamping device, intermediate mold drive cylinder device 22, electric motor 34, grip release drive device 45, stretch rod drive device 46, a cooling device described later, and the like. All operations of the blow molding machine 10 are controlled. In addition, the control device may be configured integrally with another control device such as a control device of a molded product take-out device, or among a plurality of control systems constructed in a large computer. There may be one.

  Next, the configuration of each part of the injection blow molding machine 10 will be described in detail.

  FIG. 3 is a cross-sectional view of the main part of the injection blow molding machine in the embodiment of the present invention, and is an enlarged view of part A in FIG. 2, and FIG. 4 is the outside of the preform cooling pipe of the injection blow molding machine in the embodiment of the present invention. It is a figure which shows a shape.

  As shown in FIG. 1, a female mold portion 51 as an injection mold is attached to a mold mating surface of the fixed mold 13, that is, a parting surface, by a cavity plate 13e. There may be a single female mold part 51 or a plurality of female mold parts 51. In the present embodiment, two rows of six rows in the vertical direction (direction perpendicular to the drawing in FIG. 1) are provided. The twelve female mold parts 51 are attached to the fixed mold 13. In this case, the blow molding female mold formed by the movable split mold 14 attached to the mold mounting surface of the movable platen 12 at the blowing station is also arranged in a row of six in the vertical direction, like the female mold portion 51. Are formed in two rows.

  In the fixed mold 13, a nozzle touch portion 13a to which a tip of a nozzle of a heating cylinder (not shown) is pressed, a sprue 13b as a resin flow path extending from the nozzle touch portion 13a, and a branch from the sprue 13b are branched. A runner 13 c serving as a resin flow path and a hot runner nozzle 13 d formed at the tip of the runner 13 c and communicating with the inside of each female mold 51 are formed. Thereby, the resin injected from the tip of the nozzle of the heating cylinder passes through the sprue 13b, the runner 13c, and the hot runner nozzle 13d, and is formed between each female mold part 51 and the corresponding male mold part 42b. Filled in the cavity. The injection core molds 42 are formed in two rows at positions corresponding to the respective rows of the female mold portions 51, and the root portion 42a and the male mold portion 42b are formed at positions corresponding to the respective female mold portions 51 of the respective injection core dies 42. Is arranged. That is, there are twelve root portions 42a and twelve male portions 42b.

  Here, as shown in FIG. 3, a hot nozzle 72 is provided in the hot runner nozzle 13d. The hot nozzle 72 includes a cylindrical main body portion 72a, a tip tip 72b that contacts the back surface (right side surface in FIG. 3) of the female mold portion 51, and a heating unit that includes a heater attached to the outer periphery of the main body portion 72a. 72c, and a center hole 72d as a resin flow path communicating the runner 13c and the cavity. The central hole 72d is formed to have a smaller diameter in the tip end 72b. A rod-like gate valve 71 that is moved forward or backward (moved rightward or leftward in FIG. 3) by a driving device (not shown) is disposed in the center hole 72d. As shown in FIG. 3, the gate valve 71, when advanced, enters the small diameter central hole 72d formed in the distal tip 72b to close the central hole 72d. In the retracted state, the tip end portion is detached rearward from the small diameter center hole 72d formed in the tip tip 72b to open the center hole 72d. FIG. 3 shows a closed state.

  Accordingly, since the cavity can be opened and closed by moving the gate valve 71 forward or backward, the resin can be filled into the cavity at an arbitrary timing, and the resin filled in the cavity can be filled into the runner 13c. Backflow can be prevented. Further, by heating the entire hot nozzle 72 by the heating unit 72c, the cavity can be filled with the temperature of the resin maintained at a high temperature. In the example shown in FIG. 3, resin is already filled in the cavity, and the preform 61 is formed.

  The fixed mold 13 has a cooling device. Specifically, as shown in FIG. 3, the cavity plate 13e and the female mold part 51 have a first cooling means through which a cooling medium such as cooling water flows to adjust the temperature of the cavity from the outside. A first outer refrigerant channel 65a, a second outer refrigerant channel 65b, and a third outer refrigerant channel 65c are formed. In the female mold 51, the first outer refrigerant flow path 65a is disposed at a position closest to the hot runner nozzle 13d in the axial direction of the cavity (lateral direction in FIG. 3), and the second outer refrigerant flow. The flow path 65b is disposed at a position second closest to the hot runner nozzle 13d with respect to the axial direction of the cavity, and the third outer refrigerant flow path 65c is a position farthest from the hot runner nozzle 13d with respect to the axial direction of the cavity. It is arranged. That is, the first outer refrigerant channel 65a adjusts the temperature of a portion near the tip of the preform 61, the second outer refrigerant channel 65b adjusts the temperature of a portion near the middle of the preform 61, and the first The third outer refrigerant flow path 65c adjusts the temperature of the base of the preform 61, that is, the portion near the portion where the male screw is formed.

  The first outer refrigerant channel 65a, the second outer refrigerant channel 65b, and the third outer refrigerant channel 65c will be described as the outer refrigerant channel 65 when described in an integrated manner. Further, in the example shown in FIG. 3, the outer refrigerant flow path 65 is three, but may be two, or may be four or more. The outer refrigerant passage 65 is connected to a medium supply source (not shown) via a pipe such as a hose. The medium supply source is, for example, a water tank, a water pipe, or the like, but may be of any type as long as it can supply a necessary amount of cooling medium to the outer refrigerant flow path 65. It is desirable that the medium supply source can supply the cooling medium with the temperature or flow rate adjusted. In this case, it is desirable that the temperature or flow rate of the cooling medium supplied to each of the first outer refrigerant channel 65a, the second outer refrigerant channel 65b, and the third outer refrigerant channel 65c can be adjusted independently. Thereby, the cooling capacity of the first outer refrigerant channel 65a, the second outer refrigerant channel 65b, and the third outer refrigerant channel 65c can be changed, and the temperature of each part of the preform 61 can be controlled independently. The desired temperature distribution can be obtained.

  A molded product gripping device 52 is attached to the gripping frame 32. The molded product gripping device 52 has a screw split mold 52a and a slide plate 52b to which the screw split mold 52a is attached. In the screw split mold 52a, two rows of six rows in the vertical direction are formed at positions corresponding to the female mold portions 51, and twelve screw split molds 52a are attached to the grip frame 32. ing. Then, the screw split mold 52a is formed with a spiral groove for forming a male screw on the inner peripheral surface, and is fitted into the vicinity of the inlet of the female mold portion 51. A cavity corresponding to the mouth of the preform 61 is formed between the portion 42b. Thereby, a male screw is formed on the outer periphery of the mouth of the preform 61.

  The screw split mold 52a has a configuration that can be divided in the lateral direction (vertical direction in FIG. 1), and the split part of each screw split mold 52a is attached to the split part of the slide plate 52b. It has been. The slide plate 52b extends in the vertical direction (perpendicular to FIG. 1) and is attached to the gripping frame 32. Each of the slide plates 52b has a configuration that can be divided in the horizontal direction. The split portion is attached to the grip frame 32 so as to be slidable in the lateral direction. And the half part of each slide plate 52b is urged | biased by the urging members, such as a spring member, in the center direction, and is mutually couple | bonded. Thereby, the half part of each screw split mold 52a is also urged in the center direction so as to be coupled to each other.

  A grip release driven member 52c is attached to the vicinity of the upper and lower ends of each slide plate 52b. The grip release driven member 52c has a configuration that can be divided in the lateral direction, and a half portion of each grip release follower member 52c is attached to a half portion of the slide plate 52b. When the halved portions of the slide plate 52b are urged in the central direction and coupled to each other, the halved portions of the grip release follower member 52c are also coupled to each other, and a wedge (as shown in FIG. A wedge-shaped notch is formed. The notch is at a position corresponding to the protrusion member of the grip release member. When the grip release member moves forward, the protrusion member enters the notch and the grip release follower member 52c is pushed and spread in the lateral direction. Yes. As a result, the halved portion of each slide plate 52b and the halved portion of each screw split mold 52a are also spread and divided in the lateral direction, so that after the blow molding is completed at the blowing station, the final molded product The 62 mouths can be released.

  The left and right rotating frames 31 that support the guide bar 33 to which the gripping frame 32 is attached are connected to the support column 47 via a bearing member 47a composed of a ball bearing, a roller bearing, and the like as shown in FIG. It is rotatably attached to the outer periphery. An annular driven gear 31a is attached to the side surface of one rotating frame 31, and a drive gear 34b attached to the rotating shaft 34a of the electric motor 34 meshes with the driven gear 31a. Accordingly, the rotary frame 31 can be rotated around the support column 47 by operating the electric motor 34.

  The core mold 41 has a substantially rectangular parallelepiped shape with a part of the wall surface opened, and a connecting plate 46a is disposed inside the core mold frame 41 so as to be able to advance and retract toward the movable split mold 14 side. The connection plate 46 a is attached to the extending rod driving device 46, with a part near the upper and lower ends projecting from the upper outer surface and the lower outer surface of the core mold 41. Moreover, the base part of each extending | stretching rod 44 is attached to the connection board 46a, and each extending | stretching rod 44 can be protruded simultaneously. The extending rods 44 are disposed at positions corresponding to the respective blow mold female dies formed by the movable split mold 14 and form two rows of six rows in the vertical direction.

  In the present embodiment, the drive side movable portion 14a and the driven side movable portion 14b of the movable split mold 14 are attached to the mold attachment surface of the movable platen 12 so as to be slidable in the lateral direction (vertical direction in FIG. 1). . In this case, the left and right sets of drive-side movable parts 14 a are connected to the piston rod 17 a of the split-type drive cylinder device 17, and are moved directly in the lateral direction by the split-type drive cylinder device 17. The left and right sets of driven side movable parts 14b are connected to the other set of drive side movable parts 14a by a connecting member 14d, and are moved in a direction opposite to the own set of drive side movable parts 14a. Then, by operating the left and right split mold drive cylinder devices 17 in synchronism, the drive-side movable part 14a and the driven-side movable part 14b in each set are moved and coupled in opposite directions, and the blow mold female mold Can be formed. A movable bottom member 14e is movably attached to the intermediate mold support frame 21 in the fixed bottom portion 14c. The movable bottom member 14e slightly protrudes from the fixed bottom portion 14c when blow molding is completed and the coupling between the driving side movable portion 14a and the driven side movable portion 14b is released and the mold is cut (see FIG. 1). The final molded product 62 is protruded and released from the mold.

  When the injection blow molding machine 10 is closed at the injection station and the blow station, as shown in FIG. 2, the intermediate mold support frame 21 comes into contact with the fixed platen 11, and the movable platen 12 is brought into contact with the intermediate mold support frame 21. It will be in contact. In this case, the engagement between the gripping frame engaging portion 32a and the tip end portion 33a of the guide bar 33 is released, and the gripping frame 32 in the injection station and the blowing station slides in the axial direction of the guide bar 33, and the core It is in contact with the mold 41.

  In the injection station, as shown in FIG. 3, each male part 42 b enters each female part 51 attached to the fixed mold 13. Further, the screw split mold 52a in which the half parts are coupled to each other is sandwiched between the female mold part 51 and the injection core mold 42 in a state of being fitted in the vicinity of the inlet of the female mold part 51. ing. Thereby, a cavity is formed between the inner surface of the female mold part 51 and the split mold 52a for screw and the outer surface of the male mold part 42b. The preform 61 is a substantially test tube elongated bottomed container, and a male screw is formed on the outer periphery of the opening mouth by the inner surface of the screw split mold 52a, and the screw split mold 52a is formed at the boundary of the mouth. A collar portion is formed by a gap between the female mold portion 51 and the female mold portion 51.

  The injection core mold 42 has a cooling device. Specifically, in the portion of the core mold 41 where the injection core mold 42 is disposed, as shown in FIG. 3, a cooling medium such as cooling water is used to adjust the temperature of the cavity from the inside. A first inner refrigerant channel 66a and a second inner refrigerant channel 66b are formed as cooling means through which the refrigerant flows. The male part 42b has an internal space part, and is a substantially test tube elongated bottomed container whose base side (left side in FIG. 3) is opened and whose distal end side (right side in FIG. 3) is closed. The first inner refrigerant channel 66a and the second inner refrigerant channel 66b are connected to the internal space. The internal space of the male part 42b is a columnar space extending in the axial direction (lateral direction in FIG. 3), and a cylindrical inner tube member 67 extending in the axial direction is inserted therein. Yes. The inner pipe member 67 has an end portion on the distal end side (right side in FIG. 3) opened, and an end portion on the base side (left side in FIG. 3) connected to the first inner refrigerant flow channel 66a. The end of the male part 42b on the base side is connected to the second inner refrigerant channel 66b. Thus, the male part 42b and the inner pipe member 67 form a double pipe as a cooling means, the inner pipe of the double pipe is connected to the first inner refrigerant channel 66a, and the outer pipe is Connected to the second inner refrigerant flow path 66b, the cooling medium flows through the double pipe.

  When the first inner refrigerant channel 66a and the second inner refrigerant channel 66b are described in an integrated manner, the first inner refrigerant channel 66b will be described as the inner refrigerant channel 66. The inner refrigerant channel 66 is connected to a medium supply source (not shown) via a pipe such as a hose. The medium supply source is, for example, a water tank, a water pipe, or the like, but may be of any type as long as it can supply a necessary amount of cooling medium to the outer refrigerant flow path 65. In addition, it is desirable that the medium supply source can supply the cooling medium with the temperature or flow rate adjusted. Note that the medium supply source may be the same as the medium supply source of the outer refrigerant flow path 65. Further, any one of the first inner refrigerant channel 66a and the second inner refrigerant channel 66b may be a cooling medium supply pipe, and any of them may be a cooling medium recovery pipe. That is, the flow direction of the cooling medium in the male part 42b which is a double pipe may be any. Thereby, the temperature adjustment of the preform 61 can be performed from the inside.

  Here, as shown in FIGS. 4A to 4D, the inner pipe member 67 preferably includes an uneven portion formed on the outer periphery. In the example shown in FIG. 4A, the inner tube member 67 includes a convex portion 67a and a concave portion 67b on the outer peripheral surface. The convex portion 67a has a tapered shape with an outer diameter gradually increasing, and has an outer diameter larger than that of other portions. Therefore, the interval with the inner peripheral surface of the male mold portion 42b is narrowed. Therefore, the cross-sectional area of the flow path of the cooling medium formed between the inner peripheral surface of the male part 42b and the outer peripheral surface of the inner tube member 67 decreases at the site of the convex portion 67a. On the other hand, the concave portion 67b has a tapered shape with an outer diameter gradually decreasing, and has an outer diameter smaller than that of the other portion. Therefore, the cross-sectional area of the flow path of the cooling medium increases at the concave portion 67b. The flow rate of the cooling medium is increased at a location where the cross-sectional area of the flow path is small and the cooling capacity is increased, and the flow rate of the cooling medium is reduced at a location where the cross-sectional area of the flow path is large. The degree of cooling, that is, the cooling capacity changes. Therefore, by adjusting the positions of the convex portions 67a and the concave portions 67b, the temperature of a desired portion of the male mold portion 42b can be made higher or lower than other portions. That is, the temperature distribution in the longitudinal direction of the male part 42b can be adjusted. Thereby, the temperature distribution in the longitudinal direction of the preform 61 can be adjusted from the inside.

  Moreover, in the example shown by FIG.4 (b), the inner pipe member 67 equips the outer peripheral surface with the convex part 67a. In this case, since the convex portion 67a has a substantially constant outer diameter and a larger outer diameter than other portions, the cross-sectional area of the flow path of the cooling medium decreases at the portion of the convex portion 67a. The function of the convex portion 67a is the same as the example shown in FIG.

  Further, in the example shown in FIG. 4C, the convex portions 67a provided on the outer peripheral surface of the inner tube member 67 are spiral ridges with gradually increasing pitch, that is, spiral ridges with unequal pitches. In this case, the cooling medium flows between the inner peripheral surface of the male mold portion 42b and the outer peripheral surface of the inner tube member 67 in the longitudinal direction of the male mold portion 42b, and is formed between adjacent spiral ridges. It also circulates along the spiral groove. That is, the flow form of the cooling medium becomes complicated, and the temperature adjustment effect by the cooling medium changes. Note that when the spiral groove is narrowed, the flow rate of the cooling medium is increased. Therefore, the magnitude of the temperature adjustment effect can be adjusted by adjusting the pitch of the convex portions 67a. Further, by adjusting the position of the convex portion 67a, the temperature of a desired portion of the male mold portion 42b can be made higher or lower than other portions. Thereby, the temperature distribution in the longitudinal direction of the preform 61 can be adjusted from the inside.

  Further, in the example shown in FIG. 4 (d), the convex portion 67a provided on the outer peripheral surface of the inner tube member 67 has two spiral ridges having a constant pitch, that is, multiple spiral ridges having an equal pitch. It is. The function of the convex portion 67a is the same as the example shown in FIG.

  By the way, the said convex part 67a may be formed integrally with the inner pipe member 67, and may be formed by attaching another member. For example, the convex portion 67 a shown in FIG. 4B may be a member in which a short cylindrical member is fitted into the outer peripheral surface of the inner tube member 67. Further, for example, the convex portion 67 a shown in FIGS. 4C and 4D may be one in which a spiral linear body such as a coil spring is wound around the outer peripheral surface of the inner tube member 67.

  Furthermore, the convex portion 67a and the concave portion 67b can be disposed not on the outer peripheral surface of the inner tube member 67 but on the inner peripheral surface of the male mold portion 42b. Further, the convex portion 67 a and the concave portion 67 b may be disposed on the inner peripheral surface of the inner tube member 67.

  In the blowing station, the drive side movable portion 14a and the driven side movable portion 14b are combined to form a blow molding female die. In this case, since the driving side movable portion 14a and the driven side movable portion 14b are coupled so as to wrap around the fixed bottom portion 14c from the left and right, the inner surface of the blow molding female mold is composed of the driving side movable portion 14a and the driven side movable portion. 14b, the fixed bottom part 14c, and the movable bottom member 14e, and has the shape of a bottle-shaped or bottle-shaped bottomed container.

  A screw split mold 52a holding the preform 61 is pressed against the opening of the blow molding female mold formed by the drive side movable section 14a and the driven side movable section 14b. For this reason, the flange portion of the preform 61 is pressed against the outer surface of the opening of the blow molding female mold, and the portion ahead of the flange portion enters the blow molding female mold. When the stretching rod driving device 46 is operated in this state, the stretching rod 44 protrudes toward the back side of the blow molding female mold, enters the inside of the preform 61, and blows the preform 61. Extend toward the back of the female mold. At the same time, high pressure air is blown into the preform 61 through an air flow path (not shown), so that the preform 61 is expanded and pressed against the inner surface of the female mold for blow molding. Thereby, the bottle-shaped or bottle-shaped bottomed container which has the shape of the female inner surface for blow molding can be shape | molded.

  Next, the operation of the injection blow molding machine 10 having the above configuration will be described.

  FIG. 5 is a longitudinal sectional view of a preform formed by an injection blow molding machine according to an embodiment of the present invention. FIG. 6 is a longitudinal sectional view of a preform stretched by an injection blow molding machine according to an embodiment of the present invention. FIG. 7 is a side view of the final molded product blow-molded by the injection blow molding machine in the embodiment of the present invention.

  In this case, in one molding cycle, the number of preforms 61 equal to the number of female mold parts 51, for example, 12 preforms 61 are molded by injection molding at the injection station, and the previous molding cycle is performed at the blowing station. The 12 preforms 61 molded at the injection station are blow-molded, and 12 final molded products 62 are molded.

  First, as shown in FIG. 1, from a state where the mold is opened at the injection station and the blowing station, a mold clamping device (not shown) is operated to start the mold closing. Thus, the movable platen 12 moves from the mold open state toward the mold closed state, that is, moves closer to the fixed platen 11. Then, while the movable platen 12 moves from the mold open state toward the mold close state, the intermediate mold drive cylinder device 22 is operated, and the intermediate mold support frame 21 is moved from the mold open state to the mold closed state. Toward the stationary platen 11.

  Further, when the movable platen 12 moves from the mold open state toward the mold closed state, the intermediate mold support frame 21 approaches the fixed platen 11, so that it is attached to the side surface of the rotating frame 31 on the fixed platen 11 side. The holding frame engaging portion 32 a of the holding frame 32 engaged with the leading end portion 33 a of the guide bar 33 is in contact with the leading end portion of the ejection side engaging / disengaging member attached to the fixed platen 11. Thereby, the engagement between the grip frame engaging portion 32a and the tip end portion 33a of the guide bar 33 is released, and the lock between the grip frame 32 and the guide bar 33 is released.

  Similarly, while the movable platen 12 moves from the mold open state toward the mold closed state, the intermediate mold support frame 21 approaches the movable platen 12, so that the side surface of the rotary frame 31 on the movable platen 12 side. The grip frame engaging portion 32 a of the grip frame 32 engaged with the tip portion 33 a of the attached guide bar 33 comes into contact with the tip portion of the blowing side engaging / disengaging member attached to the movable platen 12. Thereby, the engagement between the grip frame engaging portion 32a and the tip end portion 33a of the guide bar 33 is released, and the lock between the grip frame 32 and the guide bar 33 is released. The screw split mold 52a in the gripping frame 32 grips twelve preforms 61 molded at the injection station in the previous molding cycle.

  Further, while the movable platen 12 moves from the mold open state to the mold closed state, the split mold drive cylinder device 17 is operated, and the drive side movable portion 14a and the driven side movable portion 14b are moved in the lateral direction ( It is moved in the up-down direction in FIG. 1 to be joined and closed to form a blow molding female die together with the fixed bottom portion 14c. As a result, the screw split mold 52a in a state of holding the preform 61 is pressed against the opening of the blow molding female mold formed by the drive side movable section 14a and the driven side movable section 14b. Become. For this reason, the flange portion of the preform 61 is pressed against the outer surface of the opening of the blow molding female mold, and the portion ahead of the flange portion enters the blow molding female mold.

  When the movable platen 12 is in the mold closed state, the mold closing is completed at the injection station and the blowing station as shown in FIG. In this case, since the holding frame 32 at the injection station and the blowing station is unlocked from the guide bar 33, the gripping frame 32 is pushed by the injection side engaging / disengaging member and the tip of the blowing side engaging / disengaging member, and the shaft of the guide bar 33 It slides in the direction and is in contact with the core formwork 41.

  In this case, at the injection station, each male part 42 b enters each female part 51 attached to the fixed mold 13. Further, the screw split mold 52a in which the half parts are coupled to each other is sandwiched between the female mold part 51 and the injection core mold 42 in a state of being fitted in the vicinity of the inlet of the female mold part 51. ing. Thereby, a cavity is formed between the inner surface of the female mold part 51 and the split mold 52a for screw and the outer surface of the male mold part 42b. Further, in the blowing station, the flange portion of the preform 61 is pressed against the outer surface of the opening of the blow molding female die, and the portion ahead of the flange portion enters the blow molding female die.

  Subsequently, an injection process is performed at the injection station, the nozzle at the tip of the heating cylinder is pressed against the nozzle touch part 13a of the fixed mold, and the resin is injected from the tip of the nozzle. The injected resin passes through the sprue 13b, the runner 13c, and the hot runner nozzle 13d, and is filled into a cavity formed between the female mold portion 51 and the corresponding male mold portion 42b. In this case, the gate valve 71 is in a retracted state, and its distal end is released rearward from the small-diameter central hole 72d formed in the distal tip 72b to open the central hole 72d. Can be filled. When the filling of the resin is completed, the gate valve 71 moves forward, and the distal end thereof enters the small-diameter central hole 72d formed in the distal tip 72b to close the central hole 72d, as shown in FIG. Therefore, the resin filled in the cavity can be prevented from flowing back to the runner 13c.

  Here, even after the filling of the resin is completed, the closed state is continued and the resin in the cavity is cooled. In this case, a cooling medium is circulated through the first outer refrigerant channel 65a, the second outer refrigerant channel 65b, and the third outer refrigerant channel 65c to adjust the temperature of the cavity from the outside. Further, the cooling medium is circulated from the first inner refrigerant flow channel 66a to the second inner refrigerant flow channel 66b or from the opposite direction, and the temperature of the cavity is adjusted from the inner side.

  The temperature of the cavity is adjusted, for example, so that the temperature distribution of the preform 61 is as shown in FIG. FIG. 5A shows a cross section of the preform 61 molded at the injection station, and FIG. 5B shows a temperature distribution in the longitudinal direction of the preform 61 shown in FIG. In this case, as shown in FIG. 5B, the temperature of the cavity is adjusted so that the temperature of the portion indicated by a and b of the preform 61 is higher than that of the other portions.

  Specifically, a cooling medium having a desired temperature is circulated through the first outer refrigerant channel 65a, the second outer refrigerant channel 65b, and the third outer refrigerant channel 65c. As the cooling medium that circulates in the vicinity of the high temperature portion as shown by A and A of the preform 61, a cooling medium having a relatively high temperature, for example, 15 to 30 [° C.] is used, and the vicinity of other portions. As a cooling medium that circulates, a cooling medium having a relatively low temperature, for example, 5 to 15 [° C.] is used. When the resin constituting the preform 61 is PET (polyethylene terephthalate), if the temperature of the cooling medium exceeds 30 [° C.], the resin may be crystallized, and the temperature of the cooling medium is 5 [° C. ] If it is less than that, condensation may occur.

  Further, by adjusting the position of the convex part 67a or the concave part 67b of the inner pipe member 67, the length of the male part 42b is set so that the temperature of the part indicated by A and A of the preform 61 is higher than the other parts. Adjust the temperature distribution in the direction. In this case, several inner tube members 67 having different positions of the convex portions 67a or the concave portions 67b are prepared in advance, and those having the convex portions 67a or the concave portions 67b arranged at desired positions are selected and used. . The temperature of the cooling medium flowing through the male part 42b takes into consideration the temperature of the cooling medium flowing through the first outer refrigerant channel 65a, the second outer refrigerant channel 65b, and the third outer refrigerant channel 65c. Are appropriately selected. In this case, since the diameter of the preform 61 slightly contracts when cooled, the outer surface is separated from the inner peripheral surface of the female mold portion 51 and the inner surface is in close contact with the outer peripheral surface of the male mold portion 42b. Therefore, the temperature adjustment of the preform 61 is more efficient when performed from the inside than from the outside.

  On the other hand, blow molding is performed at the blowing station, the stretching rod driving device 46 is operated, and the stretching rod 44 projects toward the back side of the blow molding female mold. As a result, the preform 61 enters the inside of the preform 61, and the preform 61 is extended toward the back side of the female mold for blow molding. As a result, the portion having a high temperature extends a lot, so that the preform 61 has a cross section as shown in FIG. 6A, and the thickness at the portions indicated by a and i is thinner than the other portions. FIG. 6B shows the temperature distribution in the longitudinal direction of the preform 61 shown in FIG. 6A, and the thinner the wall, the easier it is to cool. It can be seen that the temperature is lower than other parts. Note that the portions indicated by a and i in FIG. 6A correspond to the portions indicated by a and i in FIG. 5A, respectively.

  From this, in the preform 61 before stretching, the portions indicated by a and a having a high temperature are stretched more and the thickness is reduced, and the portions having a lower temperature are stretched less and the thickness is increased. I understand. The portions indicated by a and b having a reduced thickness have a low heat capacity and cool quickly, so the temperature is low. The thick portions have a large heat capacity and cool slowly, so the temperature is high.

  Then, the preform 61 is expanded by blowing high-pressure air into the preform 61 from the blowing guide 43, the stretching rod 44, or an air flow path, an air blowing hole (not shown) formed therebetween. And press against the inner surface of the female mold for blow molding. In addition, when extending | stretching is complete | finished, the extending | stretching rod 44 will be returned to the original position from the protruded state.

  Accordingly, a bottle-like or bottle-like bottomed container having a shape as shown in FIG. 7 can be formed as the final molded product 62. The final molded product 62 has a diameter smaller than that of the other parts indicated by a and b. Note that the parts indicated by a and i in FIG. 7 correspond to the parts indicated by a and i in FIG. 6A, respectively.

  For this reason, in the preform 61 before blow molding, the portions indicated by a and a having a low thickness and a low temperature are not stretched so much in the radial direction, and a portion having a high thickness and a high temperature is stretched in the radial direction. I understand that And the thickness in the final molded product 62 becomes substantially uniform.

  When blow molding is completed, the mold clamping device is activated and the movable platen 12 moves from the mold closed state to the mold open state. The time from the start to the end of blow molding varies depending on the material, size, wall thickness, and the like of the preform 61 and the final molded product 62, but here is approximately 0.2 [seconds]. It will be explained as a thing. At this time, since the intermediate mold support frame 21 is kept closed with the fixed mold 13 by the intermediate mold drive cylinder device 22, the mold closed state is maintained at the injection station, and the resin in the cavity is cooled. continuing. The force generated by the intermediate mold drive cylinder device 22 is weaker than the force generated by the mold clamping device, but is sufficient to maintain the mold closed state when the resin in the cavity is cooled. Yes.

  Here, since the gripping frame engaging portion 32a of the gripping frame 32 is engaged with the distal end portion of the blowing side engaging / disengaging member, when the movable platen 12 moves toward the mold open state, the axis of the guide bar 33 It slides in the direction and reaches the tip 33a of the guide bar 33. Then, the grip frame engaging portion 32a is disengaged from the distal end portion of the blowing side engagement / disengagement member and is engaged with the distal end portion 33a of the guide bar 33, so that the grip frame 32 and the guide bar 33 are locked. Is done.

  Subsequently, the grip release driving device 45 is operated, and the grip release member moves toward the movable platen 12. As a result, the protruding member of the grip release member enters the notch of the grip release driven member 52c of the molded product gripping device 52 attached to the grip frame 32 and pushes the halved portion of the grip release driven member 52c laterally. . As a result, the halved portion of each slide plate 52b of the molded product gripping device 52 and the halved portion of each screw split mold 52a are also spread and divided in the horizontal direction. The grip can be released.

  Then, the molded product take-out device enters, and the final molded product 62 is taken out from the movable split mold 14 and carried out of the injection blow molding machine 10. The molded product take-out device is a device similar to a manipulator, a robot hand or the like used for taking out a molded product in a normal injection molding machine or the like. The molded product take-out device stands by at the side or upper side of the injection blow molding machine 10 and passes between the upper and lower or left and right tie bars 15 when the final molded product 62 is taken out from the movable split mold 14. Then, it enters between the movable split mold 14 and the gripping frame 32, takes out the final molded product 62 from the movable split mold 14, and exits outside the injection blow molding machine 10. Thereafter, the final molded product 62 is transported and placed on a predetermined placement place (not shown). The time required for the molded product take-out device to enter between the movable platen 12 and the gripping frame 32, take out the final molded product 62 from the movable split mold 14 and carry it out of the injection blow molding machine 10 is as follows. Although it varies depending on the type of the molded product take-out device, the size of the final molded product 62, and the like, here it will be described as being about 2.0 [seconds].

  Subsequently, when the removal of the final molded product 62 is completed, the intermediate mold drive cylinder device 22 is operated, and the intermediate mold support frame 21 moves away from the mold closed state to the mold open state, that is, away from the fixed platen 11. To move. At this time, the resin in the cavity is sufficiently cooled, and the preform 61 is molded. Note that the time from the start of injection molding until the resin is sufficiently cooled varies depending on the material, size, thickness, etc. of the preform 61, but here it is about 6.0 [seconds]. It will be explained as a thing. Since the core mold 41 moves together with the intermediate mold support frame 21, the male mold part 42 b is pulled out from the female mold part 51 attached to the fixed mold 13. In addition, since the gripping frame engaging portion 32a of the gripping frame 32 at the injection station is engaged with the tip of the injection side engaging / disengaging member, even if the intermediate mold support frame 21 moves toward the mold open state, The gripping frame 32 slides in the axial direction of the guide bar 33, and the screw split mold 52 a maintains a state where it is fitted in the vicinity of the inlet of the female mold part 51. When the grip frame 32 reaches the distal end portion 33a of the guide bar 33, the grip frame engaging portion 32a releases the engagement with the distal end portion of the ejection side engaging / disengaging member, and engages with the distal end portion 33a of the guide bar 33. As a result, the grip frame 32 and the guide bar 33 are locked.

  Subsequently, when the intermediate mold support frame 21 further moves away from the fixed platen 11, the gripping frame 32 also moves, so that the screw split mold 52 a is pulled out from the female mold part 51. In this case, the half portion of the screw split mold 52a is urged in the central direction by the urging member and is coupled to each other, so that the mouth portion of the preform 61 is gripped. In this case, the screw split mold 52a includes a spiral groove for forming a male screw on the inner peripheral surface, and a male screw is formed in the mouth portion of the preform 61 by the spiral groove, and the spiral groove and the male screw are associated with each other. Match. Further, even when a force is applied in the axial direction of the preform 61, the grip of the split portion 52a for the screw on the mouth portion of the preform 61 does not come off. Therefore, even if the preform 61 is attached to the inner surface of the female mold part 51, the preform 61 is reliably pulled out from the female mold part 51 by the screw split mold 52a.

  As a result, the gripping frame 32 at the injection station reaches a position away from the fixed mold 13 with the screw split mold 52 a gripping all twelve preforms 61. In this case, the distance from the center of the support column 47 to the fixed mold 13 and the distance from the center of the support column 47 to the movable split mold 14 are substantially equal to each other, and the rotary frame 31 rotates around the support column 47. However, the distance is such that the gripping frame 32 is not in contact with either the fixed mold 13 or the movable split mold 14.

  Subsequently, the electric motor 34 is operated to rotate the rotating frame 31 around the support column 47. As a result, the gripping frame 32 with the screw split mold 52a gripping the preform 61 moves from the injection station to the blowing station, and the other gripping frame 32 moves from the blowing station to the injection station. Note that the core mold 41 is not rotated.

  When the rotation of the rotary frame 31 is completed, the mold is opened at the injection station and the blowing station as in the beginning. Thereby, one molding cycle is completed. Thereafter, the above-described operation is repeatedly executed, and a predetermined number of molding cycles are repeated.

  Thus, in the present embodiment, when the preform 61 molded at the injection station is cooled, the temperature can be changed for each part of the preform 61. In this case, a plurality of outer refrigerant channels 65 that pass through a plurality of locations in the axial direction of the cavity are formed in the female mold 51, and cooling media having different temperatures can be circulated through the respective outer refrigerant channels 65. it can. Therefore, the preform 61 in the cavity can be cooled from the outside, and the temperature can be adjusted for each part of the preform 61. Further, the inner pipe member 67 is inserted into the internal space of the male part 42b to form a double pipe, and the cooling medium is circulated inside the double pipe. In this case, the flow rate of the cooling medium flowing between the male part 42b and the inner tube member 67 can be changed with respect to the axial direction of the cavity. Therefore, the preform 61 in the cavity can be cooled from the inside, and the temperature can be adjusted for each part of the preform 61. That is, the outer surface and inner surface of the preform 61 can be cooled and the temperature can be adjusted for each part.

  Therefore, it is possible to form the preform 61 having an appropriate temperature distribution corresponding to the material and shape of the preform 61, the shape of the final molded product 62 formed by blow molding, and the like, without requiring a heating station. Therefore, the injection blow molding machine 10 with a small and simple configuration can be obtained. Further, the time for heating the preform 61 is not required, and the time required for the molding cycle can be shortened.

  And since the temperature distribution of the preform 61 can be made appropriate, a high-quality final molded product 62 can be molded. For example, by cooling the preform 61 as shown in FIG. 5A so as to have a temperature distribution as shown in FIG. 5B, a final molded product having a shape as shown in FIG. The thickness at 62 can be made uniform. In this case, the temperature of the part of the preform 61 corresponding to the part having a smaller diameter than the other part in the final molded product 62 is set to be higher than that of the other part. Thereby, first, when the said preform 61 is extended | stretched to a longitudinal direction, a high temperature site | part will extend | stretch and become thin. And since the site | part which became thin becomes easy to cool, temperature falls from other site | parts. The other parts are thicker and higher in temperature. Therefore, when the preform 61 is subsequently stretched in the radial direction, the thinned portion has a small diameter because it is difficult to stretch because the temperature is low, and the rate of change in thickness is small. On the other hand, since the other portions are high in temperature, they are easy to stretch and have a large diameter, and the rate of change in thickness is large and thin. As a result, it is possible to obtain a final molded product 62 having a uniform wall thickness regardless of whether the diameter is small or large.

  Further, in the present embodiment, a plurality of outer refrigerant channels 65 are formed inside the female mold portion 51 that forms the outside of the cavity, and the outer refrigerant channels 65 corresponding to the respective portions in the longitudinal direction of the preform 61 are formed. It is possible to circulate cooling media having different temperatures. Therefore, with respect to the longitudinal direction of the preform 61, the cooling ratio can be changed for each part, and the preform 61 having a desired temperature distribution can be formed. Furthermore, the cooling medium is circulated inside the male mold part 42b constituting the inside of the cavity, and the inner pipe member 67 having the convex part 67a on the outer peripheral surface is inserted into the internal space of the male mold part 42b, thereby With respect to the longitudinal direction of the portion 42b, the flow rate of the cooling medium at a predetermined portion can be changed. Therefore, with respect to the longitudinal direction of the preform 61, the cooling ratio can be changed for each part, and the preform 61 having a desired temperature distribution can be formed.

  In the present embodiment, the operation when the preform 61 is stretched by the stretching rod 44 when performing blow molding has been described. However, the stretching of the preform 61 by the stretching rod 44 may be omitted.

  The present invention is not limited to the above-described embodiment, and various modifications can be made based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

It is a partial plane sectional view of the injection blow molding machine in an embodiment of the invention. It is a front fragmentary sectional view of the injection blow molding machine in an embodiment of the invention, and is a figure showing the state where a mold was closed. It is principal part sectional drawing of the injection blow molding machine in embodiment of this invention, and is the A section enlarged view of FIG. It is a figure which shows the outer side shape of the preform cooling pipe of the injection blow molding machine in embodiment of this invention. It is a longitudinal cross-sectional view of the preform shape | molded by the injection blow molding machine in embodiment of this invention. It is a longitudinal cross-sectional view of the preform extended | stretched with the injection blow molding machine in embodiment of this invention. It is a side view of the final molded product blow-molded by the injection blow molding machine in the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Injection blow molding machine 11 Fixed platen 12 Movable platen 13 Fixed mold 14 Movable split mold 21 Intermediate mold support frame 42 Injection core mold 43 Blow guide 61 Preform 62 Final molded product 65 Outer refrigerant flow path 65a First outer refrigerant Channel 65b Second outer refrigerant channel 65c Third outer refrigerant channel 66 Inner refrigerant channel 66a First inner refrigerant channel 66b Second inner refrigerant channel

Claims (12)

(A) an injection mold support device to which a fixed mold is attached;
(B) a blow mold support device to which a movable mold is attached;
(C) comprising an injection core mold and a blowing guide, and having an intermediate mold supporting apparatus disposed between the injection mold supporting apparatus and the blowing mold supporting apparatus;
(D) An injection blow molding machine that blow-molds an intermediate molded product formed by injection molding to form a final molded product,
(E) An injection blow molding machine, wherein the fixed mold and / or the injection core mold includes a cooling device that adjusts the temperature distribution of the intermediate molded product corresponding to the blow molding. The injection blow molding machine according to claim 1, wherein the cooling device can change a cooling capacity in accordance with a portion of the intermediate molded product. The injection blow molding machine according to claim 2, wherein the cooling device changes a flow rate of the cooling medium. The injection blow molding machine according to claim 2, wherein the cooling device distributes cooling media having different temperatures. The injection blow molding machine according to any one of claims 1 to 4, wherein the fixed mold cooling device includes a plurality of cooling means and adjusts a surface temperature of the intermediate molded product. (A) An injection blow molding method using a molding machine that blow molds an intermediate molded product molded by injection molding to mold a final molded product,
(B) An injection blow molding method, wherein the temperature distribution of the intermediate molded product is adjusted corresponding to blow molding. The injection blow molding method according to claim 6, wherein the temperature distribution is adjusted by changing a cooling capacity in accordance with a portion of the intermediate molded product. The injection blow molding method according to claim 7, wherein the cooling capacity is changed by changing a flow rate of the cooling medium. The injection blow molding method according to claim 7, wherein the cooling capacity is changed by circulating cooling media having different temperatures. (A) a mold for an injection blow molding machine,
(B) a male part comprising an internal space and forming the inner periphery of the preform;
(C) an inner tube member inserted into the internal space of the male mold part;
(D) having a refrigerant flow path formed between the inside of the inner pipe member, and the outer circumference of the inner pipe member and the inner circumference of the male part,
(E) The mold of the injection blow molding machine, wherein the inner tube member includes an uneven portion formed on the outer periphery. The mold of the injection blow molding machine according to claim 10, wherein the uneven portion changes in the longitudinal direction of the inner tube member. The mold of the injection blow molding machine according to claim 11, wherein the uneven portion is formed in consideration of the shape of a final molded product.

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