JP2006256280A - Injection molding machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection molding machine capable of stably operating a drive mechanism and control system of an accumulator device without being thermally affected by a piston and a plasticized resin. <P>SOLUTION: The injection molding machine is equipped with a continuous plasticizing device 11 for plasticizing a synthetic resin material, the accumulator device 12 comprising a cylinder 21, which communicates with an outflow passage of the continuous plastizing device 11, and a piston 23 provided in the cylinder 21 and temporarily storing the plasticized resin supplied from the continuous plastizicing device 11 and an injection device 13 for injecting the plasticized resin supplied from the accumulator device 12. A drive motor 45 for driving the piston 23 so as to allow the same to advance and retreat is provided to the upper part of the accumulator device 12 and a heat insulating material 32 as a heat barrier means is provided between the piston 23 and the drive motor 45. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an injection molding apparatus in which a plasticizing device for plasticizing a synthetic resin material and an injection device are connected via an accumulator device.

  In an injection molding machine that molds a molded product by injecting molten resin into an injection mold, a continuous plasticizer that plasticizes synthetic resin material, and the plasticized resin is weighed and injected into an injection mold An accumulator device is provided between the injection device, the plasticized resin supplied from the continuous plasticizing device is temporarily stored in the accumulator device, and the plastic stored in the cylinder of the accumulator device in accordance with the injection timing of the injection device. 2. Description of the Related Art A continuous plasticizing injection molding apparatus that supplies plasticized resin to an injection device by a piston is known.

  In this continuous plasticizing type injection molding apparatus, when the continuous plasticizing apparatus is continuously operated and the plasticized resin is extruded from the continuous plasticizing apparatus to the accumulator apparatus, the piston in the cylinder of the accumulator apparatus is pushed up by the resin discharge pressure. Thus, the continuous plasticizer supplies the accumulator cylinder. Further, when the piston in the cylinder is pushed down by the driving device and the opening / closing valve of the cylinder is opened, the plasticized resin stored in the cylinder is supplied to the injection cylinder of the injection device.

  When the injection plunger of the injection cylinder moves backward to measure the amount of plasticized resin required for one injection, the cylinder open / close valve closes, the injection plunger moves forward, and when the injection cylinder open / close valve opens, the injection cylinder The plasticizing resin is injected from the injection mold into the injection mold, and one molding cycle is completed.

In the continuous plasticization type injection molding apparatus constructed as described above, the bottom of the cylinder of the accumulator device is directly connected to the side wall of the injection cylinder of the injection device, and when the piston in the cylinder is pushed down by the drive device, Plasticizing resin is supplied to the injection cylinder of the injection device from the opening provided in the bottom (see, for example, Patent Document 1).
Japanese Patent No. 3,007,920

  By the way, in the continuous plasticizing type injection molding apparatus described above, the plasticizing resin is extruded from the continuous plasticizing apparatus to the cylinder of the accumulator apparatus, and the plasticizing resin is extruded from the cylinder of the accumulator apparatus to the injection cylinder of the injection apparatus. . The cylinder of the accumulator device needs to be heated by a heater in order to temporarily store the plasticized resin. Therefore, the piston is heated by the heater and the high temperature plasticizing resin. On the other hand, an upper part of the piston is provided with an electric motor such as a hydraulic cylinder or a servo motor for driving the accumulator device, and a linear scale for position control.

  Therefore, there is a problem that an electric motor such as a hydraulic cylinder or a servo motor that drives the accumulator device, and a linear scale for position control are heated by the heat of the piston and the heat of the plasticizing resin, which adversely affects driving and control.

  The present invention has been made paying attention to the above circumstances, and the purpose thereof is that the drive mechanism and control system of the accumulator device are not affected by the heat of the piston and the heat of the plasticizing resin, and can operate stably. An object of the present invention is to provide an injection molding apparatus capable of performing the above.

  In order to achieve the above-mentioned object, the present invention provides a plasticizing device for plasticizing a synthetic resin material, a cylinder communicating with an outflow passage of the plasticizing device, and a piston provided in the cylinder. An injection molding apparatus comprising: an accumulator device that temporarily stores the plasticized resin supplied from the plasticizing device; and an injection device that injects the plasticized resin supplied from the accumulator device. A drive mechanism for driving the piston back and forth is provided at the top of the accumulator device, and a heat shield means is provided between the piston and the drive mechanism.

  A second aspect of the present invention includes a plasticizing device for plasticizing a synthetic resin material, a cylinder communicating with an outflow passage of the plasticizing device, and a piston provided in the cylinder, and the plastic supplied from the plasticizing device. In an injection molding apparatus comprising an accumulator device for temporarily storing a fluorinated resin and an injection device for injecting a plasticized resin supplied from the accumulator device, an electric motor and a rotation of the electric motor are provided above the accumulator device A ball screw mechanism that converts the motion into a linear motion to drive the piston forward and backward is provided, and a heat shield means is provided between the piston and the ball screw mechanism.

  A third aspect of the present invention is characterized in that the heat shield means according to the first or second aspect is a heat insulating material.

  A fourth aspect of the present invention is characterized in that the heat shield means according to the first or second aspect is a water jacket.

  According to a fifth aspect of the present invention, a plasticizing device for plasticizing a synthetic resin material, a cylinder communicating with an outflow passage of the plasticizing device, and a piston provided in the cylinder, the plastic supplied from the plasticizing device is provided. In an injection molding apparatus comprising an accumulator device for temporarily storing a fluorinated resin and an injection device for injecting a plasticized resin supplied from the accumulator device, a drive mechanism for driving the piston forward and backward on the accumulator device And a heat shield means for blocking the rising hot air is provided at the lower part of the drive mechanism.

  According to the present invention, by providing the heat shielding means, the drive mechanism and control system of the accumulator device are not affected by the heat of the piston and the heat of the plasticizing resin, and the stable operation can be performed. is there.

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

  The schematic configuration of the continuous plasticizing injection molding apparatus will be described with reference to FIGS. 1 to 3. The continuous plasticizing apparatus 11 for plasticizing the synthetic resin material and the continuous plasticizing apparatus 11 are provided in communication with each other. The accumulator device 12 temporarily stores the supplied plasticized resin, and the injection device 13 that measures and injects the plasticized resin supplied from the accumulator device 12. The plasticizing resin injected from the injection device 13 is filled in an injection molding die described later provided in the mold clamping device 14.

  The continuous plasticizing device 11 is provided with a horizontal plasticizing cylinder 15 containing a parallel biaxial plasticizing screw, and a driving device 16 is provided on the base end side of the plasticizing cylinder 15. The drive device 16 includes an inverter motor 17 and the like, and rotational force is transmitted from the rotating shaft of the inverter motor 17 to the plasticizing screw via the gear box 18, and the parallel two-axis plasticizing screw rotates at the same speed in the same direction. It is supposed to be. The plasticizing screw is divided into screw elements having different screw shapes so as to function as, for example, a feed unit, a kneading unit, and a compression unit from the base end side in the axial direction to the tip end side. Moreover, the parallel biaxial plasticizing screw is continuously rotated in the same direction while contacting inside the plasticizing cylinder 15, and the synthetic resin material is kneaded while being heated by the heater 19, and flows out from the outflow passage 20 of the plasticizing cylinder 15. It is supposed to be.

  Therefore, the continuous plasticizing apparatus 11 can knead and plasticize the supplied synthetic resin material while heating even powder or pulverized material. Since the conventional general plasticizing apparatus is a single screw plasticizing screw, the kneading ability is low. For this reason, the powdery synthetic resin material is heated and kneaded and granulated into pellets, and the pelletized synthetic resin is supplied to the plasticizing device. Since the powdery synthetic resin material can be plasticized, a granulation step can be omitted, and labor and energy can be saved.

  Next, the accumulator device 12 will be described. A vertical cylinder 21 is provided as shown in FIGS. An opening 15 a is provided in the side wall of the cylinder 21, and the opening 15 a communicates with the outflow path 20 of the plasticizing cylinder 15. Further, a piston 23 is provided in the accumulator chamber 22 inside the cylinder 21 so as to be movable in the vertical direction. A heater 24 is wound around the cylinder 21 to heat the internal plasticizing resin and keep it in a plasticized state.

  A plate-shaped heat insulating material 25 having rigidity such as ceramics is fixed in a horizontal state at the upper end portion of the cylinder 21, and a support member 26 is overlapped and fixed on the upper surface of the heat insulating material 25. Two shaft fixing members 27 are provided symmetrically on the upper side of the support member 26 with the piston 23 in between, and a guide shaft 28 projects in the vertical direction in parallel to the piston 23 on these shaft fixing members 27. . A cylindrical case 30 fixed to the support plate 29 is fitted to the upper end portions of the guide shafts 28 so that the guide shafts 28 are kept in parallel. Further, the support member 26 is provided with a projecting ring 27 a so as to surround the shaft fixing member 27 so as to receive the grease flowing down along the guide shaft 28.

  A plate-like heat insulating material 32 is fixed to the upper end of the piston 23 via a spacer 31 as a heat insulating means having rigidity such as ceramics. A nut constituting the ball screw mechanism 33 is formed on the upper surface of the heat insulating material 32. The member 34 is overlapped and fixed. A screw hole 35 is provided in a central portion of the nut member 34 so as to penetrate in the vertical direction, and a screw shaft 36 constituting a ball screw mechanism 33 is screwed into the screw hole 35. Then, the piston 23 and the nut member 34 constituting the ball screw mechanism 33 are thermally cut off by the two heat insulating materials 25 and 32, and an electric motor 45 as a drive mechanism to be described later is used to drive the ball screw mechanism 33. The structure does not affect the heat of the heater 24 or the heat effect of the plasticizing resin in the accumulator chamber 22.

  Furthermore, fitting holes 37 are provided symmetrically on both ends of the nut member 34 with a screw hole 35 interposed therebetween. The fitting holes 37 are provided with bushes 38 that are slidably fitted to the guide shaft 28. Therefore, the nut member 34 is guided by the guide shaft 28 and moves up and down.

  A load cell 39 such as a strain gauge is provided on the upper portion of the nut member 34 to fit the screw shaft 36 constituting the ball screw mechanism 33 and measure the axial load. A bearing member 41 is provided on the upper portion of the load cell 39 via a guide tube 40 that is fitted to the screw shaft 36. The bearing member 41 is provided with a bearing 42 that rotatably supports the screw shaft 36. Furthermore, a large-diameter driven pulley 43 is fitted to the upper end portion of the screw shaft 36.

  A mounting plate 44 is fixed to the bearing member 41, and an electric motor 45 made of a servo motor is mounted on the mounting plate 44 with its rotating shaft 46 vertically and upward. A small-diameter driving pulley 47 is fitted on the rotating shaft 46 of the electric motor 45, and a belt 48 is stretched between the driving pulley 47 and the driven pulley 43.

  Therefore, the rotation of the electric motor 45 is transmitted in the order of the drive pulley 47 → the belt 48 → the driven pulley 43, and a reduction mechanism 45a is configured in which the rotation of the electric motor 45 is transmitted to the screw shaft 36 at a reduced speed. By providing the speed reduction mechanism 45a, the driving torque of the electric motor 45 can be amplified, and the electric motor 45 can be reduced in size and cost.

  Further, the electric motor 45 is mounted with its rotating shaft 46 in the vertical direction and upward, and is provided adjacent to and parallel to the screw shaft 36 constituting the ball screw mechanism 33, so that the speed reduction mechanism 45a including the electric motor 45 is located upward. The overall height of the device can be reduced, and the overall size of the device can be reduced. Further, by using a servo motor as the electric motor 45, the positioning of the piston 23 can be performed by an encoder or the like, and position measuring means such as a linear scale becomes unnecessary.

  The rotation of the screw shaft 36 that is rotated by the drive of the electric motor 45 is converted into a linear motion by the nut member 34 that is screwed with the screw shaft 36, and the nut member 34 is guided by the guide shaft 28 to move up and down. Yes.

  Since the nut member 34 and the screw shaft 36 move up and down relatively, an upper end portion of the piston 23 is provided with a shaft fitting hole 49 that forms a relief portion and a grease reservoir portion of the screw shaft 36 in the axial direction. Yes. When the nut member 34 moves up and down relatively with respect to the screw shaft 36 and the piston 23 rises integrally with the nut member 34, the lower end portion of the screw shaft 36 is immersed in the shaft fitting hole 49, and the piston 23 is moved into the nut member. The lower end of the screw shaft 36 is pulled out from the shaft fitting hole 49 when it is lowered integrally with the shaft 34.

  Moreover, since the shaft fitting hole 49 is sealed, when the lower end portion of the screw shaft 36 is immersed in the shaft fitting hole 49, it is necessary to escape air inside the shaft fitting hole 49. Therefore, the nut member 34 is provided with an air passage 50 that communicates the shaft fitting hole 49 of the piston 23 with the outside to form an air vent. The air passage 50 communicates with a lateral hole 50a penetrating the nut member 34 in the lateral direction, a longitudinal hole 50b communicating with the lateral member 50a in the longitudinal direction and penetrating the nut member 34, the spacer 31, and the heat insulating material 32 with a longitudinal hole 50b. The extended vertical hole 50 c communicates with the inner bottom portion of the shaft fitting hole 49 along the 23 shaft fitting holes 49. Then, when the piston 23 rises integrally with the nut member 34 and the lower end portion of the screw shaft 36 is immersed in the shaft fitting hole 49, the air inside the shaft fitting hole 49 escapes to the outside through the air passage 50. It is like that. At this time, the grease accumulated in the shaft fitting hole 49 can be released to the outside through the air passage 50 at the same time.

  A cylinder head 51 is fixed to the lower end portion of the cylinder 21 with a bolt 52. The cylinder head 51 is provided with a cavity 54 having a tapered concave surface 53 that tapers downward. A tapered convex surface 55 that tapers downward is formed at the lower end of the piston 23 so as to be in close contact with the tapered concave surface 53 of the cylinder head 51.

  The cavity 54 of the cylinder head 51 communicates with a large-diameter hole fitting hole 57 via a small-diameter hole communication hole 56. A connecting cylinder 59 having a resin outlet 58 concentric with the small-diameter communication hole 56 is fitted into the fitting hole 57.

  The connection tube 59 is connected to the cylinder head 51 so as to be movable in the axial direction and the circumferential direction. Further, a tapered taper pipe 61 is integrally provided at the upper end portion of the connection tube 59 so as to have a thin portion 60 in close contact with the inner peripheral surface of the communication hole 56 so as to seal the cylinder head 51 and the connection tube 59. The means 62 is comprised.

  That is, the temperature of the plasticizing resin in the accumulator chamber 22 ranges from 160 ° C. to 230 ° C. Even if the cylinder 21 expands in the axial direction due to the heat of the plasticizing resin, the cylinder 21 is twisted in the circumferential direction due to strain or the like. Even if this occurs, the connecting cylinder 59 is connected to the cylinder head 51 so as to be movable in the axial direction and the circumferential direction, so that the injection cylinder 64 of the injection device 13 connected to the cylinder 21 is affected by deformation and the like. It is comprised so that it may not exert. Further, the thin portion 60 is expanded by the resin pressure of the plasticizing resin in the cylinder 21 and is brought into close contact with the inner peripheral surface of the communication hole 56 of the cylinder head 51 to constitute a sealing means 62 for preventing resin leakage.

  Further, a valve block 63 is fixed to the lower end portion of the connection tube 59. The valve block 63 is fixed to the side wall of the horizontal injection cylinder 64 of the injection device 13 with bolts 65. Therefore, an accumulator device 12 is mounted on the injection device 13. The valve block 63 is provided with a resin outflow path 66 concentrically with the resin outlet 58 of the connecting cylinder 59, and an open / close valve 67 formed of a rotary valve is provided in the resin outflow path 66.

  Next, the injection device 13 will be described. As shown in FIGS. 1 and 3, an injection plunger 68 is provided inside the injection cylinder 64 so as to be able to advance and retract. Around the injection cylinder 64, a heater (not shown) that heats the internal plasticizing resin and maintains the molten state is wound. Further, a measuring chamber 69 is formed in the inner cavity of the tip side of the injection cylinder 64. The measuring chamber 69 communicates with a resin outflow passage 66 provided in the cylinder 21 of the accumulator device 12 and is connected to an injection nozzle 70.

  The injection cylinder 64 is mounted on the moving frame 71 together with the continuous plasticizer 11, and the moving frame 71 is mounted on the fixed frame 72. The moving frame 71 is connected to a frame driving device 75 including an electric motor 73 and a ball screw mechanism 74 so that the injection device 13 moves forward and backward together with the continuous plasticizing device 11. As shown in FIGS. 1, 9, and 10, a cylinder support member 76 as a rigid structure is fixed to the front side of the moving frame 71, and the base end portion of the injection cylinder 64 is fixed by the cylinder support member 76. Support. An accumulator support member 77 is provided above the cylinder support member 76, and the cylinder 21 of the accumulator device 12 is fixed to the accumulator support member 77.

  That is, the accumulator device 12 has a side portion fixed to the continuous plasticizing device 11 and a lower portion fixed to the injection cylinder 64. However, since the accumulator device 12 is large in weight, a structure that supports the cylinder support member 76 in order to prevent the injection cylinder 64 from being deformed downward by the weight of the accumulator device 12 is adopted.

  Further, an accumulator support member 77 is supported on the upper surface of the cylinder support member 76 so as to be slidable in the axial direction of the injection cylinder 64. That is, as shown in FIG. 9, the accumulator support member 77 is provided with flange portions 77b and 77c projecting left and right above and below the base portion 77a. The upper flange portion 77b is fixed to a mounting plate 21a attached to the side wall of the cylinder 21 by a bolt 77d. The lower flange portion 77c is slidably supported by a receiving piece 77f attached to the upper surface of the cylinder support member 76 by a bolt 77e. Therefore, when the injection cylinder 64 is heated by the heat of the plastic resin or the heater and expands in the axial direction, the injection cylinder 64 slides between the cylinder support member 76 and the accumulator support member 77, absorbs the thermal expansion, and deforms into the accumulator device 12. It is configured so as not to affect.

  As shown in FIGS. 10 and 11, the moving frame 71 is provided with a guide rail 78 along the moving direction. A moving block 79 is mounted on the guide rail 78. The moving block 79 is formed to extend in the width direction on the moving frame 71, and nut members 81 constituting the ball screw mechanism 80 are respectively provided in parallel at both ends of the moving block 79.

  The cylinder support member 76 facing the moving block 79 is provided with bearings 82 concentrically with the nut member 81, and a screw shaft 83 constituting a ball screw mechanism 80 is rotatably supported by these bearings 82. The pair of screw shafts 83 is screwed into the nut member 81, and the moving block 79 is guided by the guide rail 78 and moves by the rotation of the screw shaft 83.

  Further, a driven pulley 84 is fitted to the pair of screw shafts 83. An electric motor 85 made of a servo motor is fixed to the cylinder support member 76 located above the driven pulley 84, and a drive pulley 86 is fitted on the rotating shaft of the electric motor 85. A belt 87 is stretched between the driving pulley 86 and the driven pulley 84. Then, the rotation of the screw shaft 83 that is rotated by driving the electric motor 85 is converted into a linear motion by the nut member 81 that is screwed with the motor shaft 85, and the moving block 79 is guided by the guide rail 78 and moved together with the nut member 81. It is supposed to be.

  Further, a through hole 88 is provided at the rear end portion of the injection cylinder 64 of the injection device 13, and a plunger rod 89 of the injection plunger 68 projects rearward through the through hole 88. The protruding end of the plunger rod 89 is connected to the moving block 79 via a connecting tool 90. Then, the movement of the moving block 79 causes the injection plunger 68 to advance and retreat inside the injection cylinder 64.

  The injection nozzle 70 of the injection cylinder 64 is joined to a nozzle touch surface 92 of an injection mold 91 provided in the mold clamping device 14 at the time of injection. The injection mold 91 is provided with a cavity (not shown) that communicates with the nozzle touch surface 92 via a resin passage, and a molded product is molded by filling the cavity with a plasticizing resin.

  Next, the operation of the continuous plasticizing injection molding apparatus configured as described above will be described. A material in which a synthetic resin material, for example, a powder such as polypropylene and a reinforcing or filling material such as mica is mixed, is supplied to the plasticizing cylinder 15 of the continuous plasticizing device 11. The inverter motor 17 of the continuous plasticizing apparatus 11 is continuously driven, and the rotation of the inverter motor 17 is transmitted to the biaxial plasticizing screw via the gear box 18. The plasticizing screw has a screw that functions as a feed part, a kneading part, and a compression part in the axial direction, continuously rotates in the same direction while contacting inside the plasticizing cylinder 15, and is heated by the heater 19, The powdery synthetic resin material is uniformly heated and melted and kneaded to become a plasticized resin.

  The plasticizing resin is extruded from the outflow passage 20 of the plasticizing cylinder 15 and is extruded into the cylinder 21 of the accumulator device 12, and the plasticizing resin is accumulated therein.

  During this time, the injection plunger 68 of the injection device 13 performs the injection and pressure holding process one cycle before. When this pressure holding step is completed, the injection plunger 68 is retracted and the opening / closing valve 67 of the cylinder 21 of the accumulator device 12 is opened. Accordingly, the plasticized resin in the accumulator chamber 22 flows from the resin outflow passage 66 into the measuring chamber 69 of the injection cylinder 64.

  At this time, the electric motor 45 of the accumulator device 12 rotates, and power is transmitted to the drive pulley 47 → the belt 48 → the driven pulley 43 → the screw shaft 36. As the screw shaft 36 rotates, the nut member 34 is guided by the guide shaft 28 and descends. Since the piston 23 is connected to the nut member 34, the piston 23 is lowered to the push limit position.

  As the piston 23 descends, the lower portion of the accumulator chamber 22, that is, the cavity 54 of the cylinder head 51 is increased by the resin pressure of the plasticizing resin, and the thin wall portion 60 of the connection tube 59 is expanded by the resin pressure. This is in close contact with the inner peripheral surface of the communication hole 56 and prevents resin leakage.

  When a predetermined amount of plasticizing resin necessary for one injection flows out of the accumulator chamber 22 into the measuring chamber 69 of the injection cylinder 64 and is measured in this manner, the on-off valve 67 is closed. Then, the electric motor 45 of the accumulator device 12 rotates in the reverse direction, and power is transmitted to the drive pulley 47 → the belt 48 → the driven pulley 43 → the screw shaft 36. As the screw shaft 36 rotates in the reverse direction, the nut member 34 is guided by the guide shaft 28 and raised. Since the piston 23 is connected to the nut member 34, the piston 23 moves up. As the piston 23 rises, the lower end portion of the screw shaft 36 is immersed in the shaft fitting hole 49, and air and grease inside the shaft fitting hole 49 escape to the outside through the air passage 50.

  On the other hand, the electric motor 85 of the injection device 13 rotates and power is transmitted to the drive pulley 86 → the belt 87 → the driven pulley 84 → the screw shaft 83. The nut member 81 is attracted by the rotation of the screw shaft 83, and the nut member 81 is guided by the guide rail 78 together with the moving block 79 to advance. Since the plunger rod 89 is connected to the moving block 79, the injection plunger 68 moves forward integrally with the plunger rod 89, and the plasticizing resin in the measuring chamber 69 is injected from the injection nozzle 70 into the cavity of the injection mold 91. And molding.

  As described above, the continuous plasticizer 11 operates continuously, whereas the injection device 13 operates intermittently to inject the plasticized resin into the injection mold 91 to perform molding. The plasticized resin continuously delivered from the device 11 can be temporarily stored in the accumulator device 12, and the plasticized resin can flow from the accumulator device 12 into the measuring chamber 69 in accordance with the injection timing of the injection device 13.

  FIG. 12 shows a second embodiment of the present invention, and the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. A plate-like first heat insulating material 101 as a heat shield means having rigidity such as ceramics is provided at the upper end of the piston 23 of the present embodiment. The first heat insulating material 101 includes a cylindrical portion 102 and a flange portion 103 formed integrally with the cylindrical portion 102, and the cylindrical portion 102 is inside an axis fitting hole 49 provided at the upper end portion of the piston 23. The flange 103 is fixed to the upper end surface of the piston 23 with a bolt 104. A plate-like second heat insulating material 105 as a heat insulating means having rigidity such as ceramics is fixed on the upper surface of the first heat insulating material 101, and a ball screw mechanism 33 is fixed on the upper surface of the second heat insulating material 105. Are stacked and fixed. A screw hole 35 is provided in a central portion of the nut member 34 so as to penetrate in the vertical direction, and a screw shaft 36 constituting a ball screw mechanism 33 is screwed into the screw hole 35. The piston 23 and the nut member 34 constituting the ball screw mechanism 33 are thermally shut off by the two heat insulating materials 101 and 105, and the heater 24 is added to the electric motor 45 as a drive mechanism that drives the ball screw mechanism 33. The structure is such that the heat does not affect the heat of the plasticizing resin in the accumulator chamber 22.

  FIG. 13 shows a third embodiment of the present invention, and the same components as those in the first and second embodiments are denoted by the same reference numerals and description thereof is omitted. At the upper end of the piston 23 of the present embodiment, a plate-like heat insulating material 106 is provided as heat shielding means having rigidity such as ceramics. The heat insulating material 106 includes a cylindrical portion 102 and a flange portion 103 formed integrally with the cylindrical portion 102, and the cylindrical portion 102 is formed on an inner peripheral surface of a shaft fitting hole 49 provided in the upper end portion of the piston 23. The hook 103 is fixed to the upper end surface of the piston 23 by a bolt 104.

  A water jacket 107 as heat shielding means is fixed to the upper surface of the heat insulating material 106, and a nut member 34 constituting the ball screw mechanism 33 is fixed to the upper surface of the water jacket 107 in an overlapping manner. The water jacket 107 is provided with a cooling water passage 108 for passing cooling water through a metal block having excellent thermal conductivity, and forcibly cools between the heat insulating material 106 and the nut member 34. The piston 23 and the nut member 34 constituting the ball screw mechanism 33 are thermally cut off by the heat insulating material 106 and the water jacket 107, and the electric motor 45 serving as a drive mechanism for driving the ball screw mechanism 33 is connected to the heater 24. The structure does not affect heat or the heat effect of the plasticizing resin in the accumulator chamber 22.

  FIG. 14 shows a fourth embodiment of the present invention. The same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. In the outer peripheral wall at the upper end portion of the piston 23 of the present embodiment, a plurality of heat radiation holes 109 communicating the inside and the outside of the shaft fitting hole 49 are provided radially. On the other hand, a plurality of blades 110 facing the inside of the shaft fitting hole 49 are provided radially at the lower end portion of the screw shaft 36 constituting the ball screw mechanism 33.

  Accordingly, when the screw shaft 36 of the ball screw mechanism 33 rotates, the air inside the shaft fitting hole 49 is agitated by the blades 110 and is discharged to the outside through the plurality of heat radiation holes 109. Thus, even if the piston 23 is heated by the heater 24 or plasticizing resin, the electric motor 45 as a drive mechanism that drives the ball screw mechanism 33 by the heat radiation action causes the heat of the heater 24 or plasticization in the accumulator chamber 22. The structure does not affect the heat of the resin.

  FIG. 15 shows a fifth embodiment of the present invention. The same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. In this embodiment, a nut member 112 of a ball screw mechanism 111 that drives the piston 23 of the accumulator device 12 to advance and retreat is provided on the support member 114 via a bearing 113. On the other hand, a drive motor 116 is attached to the frame 115 with the rotating shaft 117 facing downward. A pulley 118 is provided on the rotating shaft 117, and the pulley 118 is linked to a pulley 119 of the nut member 112 of the ball screw mechanism 111 via a belt 120.

  In addition, a heat shield plate 121 is fixed to the support member 114 below the drive motor 116 by a fixing screw 122, and a heat shield means for blocking hot air rising from the cylinder 21 and the piston 23 by the heat shield plate 121 is configured. is doing. That is, the electric motor 116 as a drive mechanism for driving the ball screw mechanism 111 is configured not to be affected by the heat of the heater 24 or the heat of the plasticizing resin in the accumulator chamber 22. The heat shield 121 also serves to receive grease or the like dripping from a power transmission system including the electric motor 116.

  According to the above-described embodiment, an electric motor is used as a drive source for the accumulator device and the injection device, and the ball screw mechanism is driven to move the piston in the cylinder forward and backward, thereby making it possible to make the device all electric, saving energy, It has the effect of contributing to environmental protection. However, the present invention has the same effect even when it is driven by hydraulic pressure or an air cylinder as a drive source of the accumulator device and the injection device.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

The side view of the injection molding apparatus which shows 1st Embodiment of this invention. The top view of the injection molding apparatus of the embodiment. The side view of the injection molding apparatus of the embodiment. The top view of the accumulator apparatus of the embodiment. Sectional drawing which shows the accumulator apparatus of the embodiment and follows the AA line of FIG. The longitudinal section side view of the accumulator device of the embodiment. The accumulator apparatus of the embodiment is shown, (a) is a longitudinal side view, (b) is a cross-sectional view along the line CC. The vertical side view which expanded a part of accumulator apparatus of the embodiment. The figure which shows the accumulator apparatus of the embodiment and was seen from the arrow B direction of FIG. The front view of the injection device of the embodiment. Sectional drawing which shows the injection apparatus of the embodiment, and follows the DD line | wire of FIG. The vertical side view which shows the accumulator apparatus of 2nd Embodiment of this invention. The vertical side view which shows the accumulator apparatus of 3rd Embodiment of this invention. The vertical side view which shows the accumulator apparatus of 4th Embodiment of this invention. The schematic block diagram of the injection molding apparatus of 5th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Plasticizing apparatus, 12 ... Accumulator apparatus, 13 ... Injection apparatus, 21 ... Cylinder, 23 ... Piston, 32 ... Thermal insulation (heat insulation means), 33 ... Ball screw mechanism, 34 ... Nut member, 36 ... Screw shaft, 45 ... Drive motor

Claims (5)

A plasticizing device for plasticizing a synthetic resin material;
An accumulator device comprising a cylinder communicating with the outflow passage of the plasticizing device and a piston provided in the cylinder, and temporarily storing the plasticized resin supplied from the plasticizing device;
An injection device for injecting the plasticized resin supplied from the accumulator device;
In an injection molding apparatus comprising:
An injection molding apparatus, wherein a drive mechanism for driving the piston forward and backward is provided at an upper part of the accumulator device, and a heat shield means is provided between the piston and the drive mechanism. A plasticizing device for plasticizing a synthetic resin material;
An accumulator device comprising a cylinder communicating with the outflow passage of the plasticizing device and a piston provided in the cylinder, and temporarily storing the plasticized resin supplied from the plasticizing device;
An injection device for injecting the plasticized resin supplied from the accumulator device;
In an injection molding apparatus comprising:
An electric motor and a ball screw mechanism for converting the rotation of the electric motor into a linear motion to drive the piston forward and backward are provided at the upper part of the accumulator device, and a heat shield means is provided between the piston and the ball screw mechanism. An injection molding apparatus characterized by that.   The injection molding apparatus according to claim 1 or 2, wherein the heat shield means is a heat insulating material.   The injection molding apparatus according to claim 1 or 2, wherein the heat shield means is a water jacket. A plasticizing device for plasticizing a synthetic resin material;
An accumulator device comprising a cylinder communicating with the outflow passage of the plasticizing device and a piston provided in the cylinder, and temporarily storing the plasticized resin supplied from the plasticizing device;
An injection device for injecting the plasticized resin supplied from the accumulator device;
In an injection molding apparatus comprising:
An injection molding apparatus, wherein a driving mechanism for driving the piston back and forth is provided at an upper portion of the accumulator device, and a heat shield means for blocking hot air rising at the lower portion of the driving mechanism is provided.

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