Injection molding system and molded product extrusion method

Abstract

To provide an injection molding system that can simplify a control system of an injection molding device.SOLUTION: An injection molding system includes an injection molding device which performs injection molding of a molded product using molds composed of a fixed mold and a movable mold assembled to the fixed mold. The injection molding device comprises: a fixed mold attaching part to which the fixed mold is attached; a platen to which the movable mold is attached so as to face the fixed mold in a predetermined mold clamping direction and which is movable parallel to the mold clamping direction; a toggle-type mold clamping mechanism which clamps the fixed mold and the movable mold by moving the platen in the mold clamping direction, and performs mold opening of the fixed mold and the movable mold by moving the platen in a mold opening direction opposite to the mold clamping direction; and an extrusion member which is provided so that its position relative to the fixed mold attaching part does not change, and extrudes the molded product out of the movable mold in response to the mold opening by the toggle-type mold clamping mechanism.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] This disclosure relates to an injection molding system and a method for extruding a molded article. [Background technology]

[0002] Research and development is being conducted on injection molding using molding materials including resins and metal powders.

[0003] In this regard, a mechanism is known in which an injection molding apparatus using a toggle-type clamping mechanism is provided with an actuator that causes the toggle-type clamping mechanism to clamp and open the fixed and movable molds that make up the mold, as well as a dedicated actuator for protruding an ejector pin that pushes the molded product out of the movable mold after injection molding, and in which the dedicated actuator pushes out the ejector pin to push out the molded product from the movable mold (see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-192651 Summary of the Invention [Problem to be solved by the invention]

[0005] However, since the mechanism described in Patent Document 1 has two actuators as described above, the control system of the mechanism can become complicated, which is undesirable because it increases the manufacturing cost of the mechanism. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, one aspect of the present disclosure is an injection molding system including an injection molding apparatus that performs injection molding of a molded product using a mold composed of a fixed mold and a movable mold assembled to the fixed mold, wherein the injection molding apparatus is an injection molding system comprising: a fixed mold mounting portion to which the fixed mold is attached; a platen to which the movable mold is attached so as to face the fixed mold in a predetermined mold clamping direction and which is movable parallel to the mold clamping direction; a toggle-type mold clamping mechanism that clamps the fixed mold and the movable mold by moving the platen in the mold clamping direction and opens the fixed mold and the movable mold by moving the platen in a mold opening direction opposite the mold clamping direction; and an extrusion member that is arranged so that its position relative to the fixed mold mounting portion does not change and that extrudes the molded product from the movable mold in response to the mold opening by the toggle-type mold clamping mechanism.

[0007] Furthermore, in order to solve the above-mentioned problems, one aspect of the present disclosure is a molded product extrusion method in an injection molding apparatus that performs injection molding of a molded product using a mold composed of a fixed mold and a movable mold assembled to the fixed mold, in which the molded product is extruded from the movable mold, wherein the injection molding apparatus comprises: a fixed mold mounting portion to which the fixed mold is attached; a platen to which the movable mold is attached so as to face the fixed mold in a predetermined mold clamping direction and which is movable parallel to the mold clamping direction; a toggle-type mold clamping mechanism that clamps the fixed mold and the movable mold together by moving the platen in the mold clamping direction and opens the fixed mold and the movable mold together by moving the platen in a mold opening direction opposite the mold clamping direction; and a pusher member that is arranged so that its position relative to the fixed mold mounting portion does not change, and the molded product extrusion method comprises: moving the platen in the mold opening direction by the toggle-type mold clamping mechanism, causing the pusher member to push the molded product out of the movable mold. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a front view showing an example of the configuration of an injection molding system 1. FIG. [Figure 2] FIG. 2 is a perspective view of the injection molding system 1 shown in FIG. [Figure 3] FIG. 2 is a perspective view showing an example of the configuration of an injection molding device 20. [Figure 4] FIG. 2 is a side view of the injection molding apparatus 20 in a clamped state in which the mold 21 is closed. [Figure 5] FIG. 2 is a side view of the injection molding apparatus 20 in a mold open state with the mold 21 open. [Figure 6] 10 is a perspective view showing an example of the state of the periphery of the crosshead XH when the movable mold 21CR is located at the separated position. FIG. [Figure 7] FIG. 7 is a front view of the crosshead XH shown in FIG. 6. [Figure 8] 10 is a diagram showing an example of the state of the periphery of the crosshead XH when the movable mold 21CR is not positioned at the separated position. FIG. [Figure 9] 10 is a diagram for explaining that a movable mold 21CR attached to a platen PL is bent when mold clamping is performed by a toggle-type mold clamping mechanism TG. FIG. [Figure 10] 1 is a side view showing a first modified example of the configuration of the injection molding device 20. FIG. [Figure 11] FIG. 10 is a top view showing an example of an injection molding system 1 in which the drive unit MT of the toggle-type mold clamping mechanism TG overlaps with the toggle mechanism TGM in a direction perpendicular to the center axis of the ball screw PS2. [Figure 12] 2 is a diagram showing an example of the configuration of a first tie bar TB1 among four tie bars provided in an injection molding apparatus 20. FIG. [Figure 13] FIG. 10 is a side view showing an example of an injection molding apparatus 20 in which each of the first tie bar TB1 to the fourth tie bar TB4 is attached to the base B2 of the toggle-type mold clamping mechanism TG by a double nut. [Figure 14] FIG. 14 is a perspective view of the injection molding apparatus 20 shown in FIG. [Figure 15] FIG. 10 is a perspective view showing an example of an injection molding apparatus 20 in which a mold thickness adjustment mechanism is attached to a base B2. [Figure 16]FIG. 16 is a rear view of the injection molding apparatus 20 shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Embodiment> Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0010] <Injection molding system overview> First, an outline of an injection molding system according to an embodiment will be described.

[0011] An injection molding system according to an embodiment includes an injection molding apparatus that performs injection molding of a molded product using a mold consisting of a fixed mold and a movable mold assembled to the fixed mold. The injection molding apparatus includes a fixed mold mounting portion, a platen, a toggle-type clamping mechanism, and an ejector member. The fixed mold is mounted to the fixed mold mounting portion. The movable mold is mounted to the platen so as to face the fixed mold in a predetermined clamping direction and is movable parallel to the clamping direction. The toggle-type clamping mechanism clamps the fixed mold and the movable mold by moving the platen in the clamping direction, and opens the fixed mold and the movable mold by moving the platen in a mold opening direction opposite the clamping direction. The ejector member is arranged so that its position relative to the fixed mold mounting portion does not change, and pushes the molded product out of the movable mold in response to mold opening by the toggle-type clamping mechanism.

[0012] As a result, the injection molding system of the embodiment can simplify the control system of the injection molding device compared to when a molded product is pushed out of a movable mold by moving an ejection member in the mold clamping direction using an actuator or the like.

[0013] The configuration of the injection molding system according to the embodiment will be described in detail below.

[0014] <Injection molding system configuration> The configuration of the injection molding system according to the embodiment will be described below using the injection molding system 1 as an example.

[0015] Fig. 1 is a front view showing an example of the configuration of an injection molding system 1. Fig. 2 is a perspective view of the injection molding system 1 shown in Fig. 1.

[0016] Here, the three-dimensional coordinate system TC is a three-dimensional Cartesian coordinate system that indicates directions in a drawing in which the three-dimensional coordinate system TC is drawn. Hereinafter, for convenience of explanation, the X-axis in the three-dimensional coordinate system TC will be simply referred to as the X-axis. Hereinafter, for convenience of explanation, the Y-axis in the three-dimensional coordinate system TC will be simply referred to as the Y-axis. Hereinafter, for convenience of explanation, the Z-axis in the three-dimensional coordinate system TC will be simply referred to as the Z-axis. Hereinafter, as an example, a case will be described in which the negative direction of the Z-axis coincides with the direction of gravity. Therefore, hereinafter, for convenience of explanation, the positive direction of the Z-axis will be referred to as upward or simply "up," and the negative direction of the Z-axis will be referred to as downward or simply "down."

[0017] As shown in FIGS. 1 and 2, the injection molding system 1 includes a housing 10, an injection molding apparatus 20, a material supplying apparatus 30, a dryer 40, a temperature regulator 50, a controller 60, a robot 70, an inspection apparatus 80, a movement mechanism 90, and a power supply unit 100 that supplies power to each of these devices. FIG. 1 shows the injection molding system 1 with the side cover 11 removed. FIG. 2 shows the injection molding system 1 with the side cover 11 attached to the side of the housing 10. The housing 10 includes an upper cover 13 that covers the top of a first base 12 (described below). In FIGS. 1 and 2, the upper cover 13 is indicated by a dashed line. The upper cover 13 is preferably made of transparent glass or resin so that the internal working status can be visually observed from the outside. Part or all of the upper cover 13 may be configured to be removable from the housing 10. The injection molding system 1 may also be configured without the side cover 11.

[0018] The injection molding device 20 is a device that molds a molded product by injecting plasticized material into a mold 21. For this purpose, a mold 21 is attached to the injection molding device 20. A hopper 22 that receives a supply of material is also connected to the injection molding device 20. The configuration of the injection molding device 20 will be described in detail below.

[0019] The mold 21 attached to the injection molding apparatus 20 may be made of metal or resin. The mold 21 is composed of a fixed mold 21CV and a movable mold 21CR attached to the fixed mold 21CV. The fixed mold 21CV is fixed so as not to move relative to a mounting base BS of the injection molding apparatus 20. To avoid cluttering the illustrations, the mounting base BS, the fixed mold 21CV, and the movable mold 21CR are not shown in FIGS. 1 and 2 . The movable mold 21CR is movable parallel to a predetermined clamping direction and is attached to the fixed mold 21CV by moving in the clamping direction. The following describes, as an example, a case where the clamping direction coincides with the negative direction of the Y-axis. The mold 21 may also be referred to as a molding die.

[0020] The material supply device 30 is a device that stores the material used in the injection molding apparatus 20 and supplies the stored material to the injection molding apparatus 20. In this embodiment, pellet-shaped resin material is fed into the material supply device 30 from outside. As shown in FIG. 2 , a door 14 is provided on the side cover 11 for feeding the material into the material supply device 30. The material stored in the material supply device 30 is dried by a dryer 40 connected to the material supply device 30. The material supply device 30 and the injection molding apparatus 20 are connected by a pipe 23. The material supply device 30 is equipped with a compressed air pump 31. The material dried by the dryer 40 is pressure-fed from the material supply device 30 through the pipe 23 by compressed air supplied from the compressed air pump 31 and supplied to a hopper 22 provided in the injection molding apparatus 20. Various dryers, such as a hot air dryer, a dehumidifying hot air dryer, or a reduced-pressure heat transfer dryer, can be used as the dryer 40.

[0021] The temperature regulator 50 is a device that regulates the temperature of the mold 21 provided in the injection molding apparatus 20. The temperature regulator 50 and the mold 21 are connected by piping (not shown), and the temperature is regulated by circulating a heat transfer medium such as water or oil through the piping.

[0022] The robot 70 is a device that picks up a molded product extruded from the movable die 21CR of the mold 21 by the injection molding apparatus 20 and places it on an inspection apparatus 80, a tray 91 for transporting molded products, or the like. The robot 70 of this embodiment is configured as a horizontal articulated robot with a built-in robot controller. A vacuum suction device is provided at the end of the robot 70 as an end effector. The robot 70 uses this vacuum suction device to vacuum-suck the molded product extruded from the movable die 21CR in the injection molding apparatus 20. The vacuum suction device is driven by a vacuum generator connected to a compressed air pump 31. The robot 70 is not limited to a horizontal articulated robot, and may also be configured as a vertical articulated robot with multiple axes. The robot controller may not be built into the robot 70, but may be located somewhere in the housing 10, such as the second base 15 described below.

[0023] The inspection device 80 is a device that inspects molded articles removed from the movable mold 21CR by the robot 70. In this embodiment, the inspection device 80 is equipped with one camera 81 and two rows of transport mechanisms 82. The camera 81 is capable of reciprocating parallel to the X axis. Each transport mechanism 82 is capable of reciprocating parallel to the Y axis. The operations of the camera 81 and the transport mechanisms 82 are controlled by the controller 60. Molded articles are alternately placed on each transport mechanism 82 by the robot 70. The molded articles placed on each transport mechanism 82 are alternately transported to a position where the camera 81 can take an image. The camera 81, while reciprocating parallel to the X axis, captures images of the molded articles transported to the photography position by each transport mechanism 82. The inspection device 80 performs an appearance inspection of the molded articles based on the captured images.

[0024] The moving mechanism 90 is a mechanism for moving a tray 91 on which a molded product is placed by the robot 70 to a removal position where the molded product can be removed from the outside. The moving mechanism 90 is controlled by the controller 60. The moving mechanism 90 includes a slide table and a fixed table on which the tray 91 is placed. The slide table is a table that moves on rails parallel to the X-axis. The fixed table is provided adjacent to the slide table and moves the tray 91 between the slide table and the fixed table parallel to the Y-axis. The slide table and the fixed table are equipped with ball rollers throughout the range over which the tray 91 moves. The moving mechanism 90 includes actuators for moving the tray 91 on the slide table and the fixed table, and an actuator for moving the slide table on the rail. In this embodiment, the robot 70 transports molded products removed from the injection molding apparatus 20 to the inspection apparatus 80, and places the molded products inspected by the inspection apparatus 80 on the tray 91 set in the moving mechanism 90. When the molded products are placed on the tray 91, the moving mechanism 90 transports the tray 91 to a position where it can be removed from the outside. Two trays 91 are set in the moving mechanism 90. The moving mechanism 90 moves the trays 91 along a predetermined path on a slide base and a fixed base, thereby moving them alternately to positions where they can be removed. The trays 91 may also be called a pallet. The moving mechanism 90 may also be called a pallet changer.

[0025] The controller 60 is a device that performs overall control of the injection molding apparatus 20, the robot 70, the inspection apparatus 80, and the movement mechanism 90. In this embodiment, the controller 60 is configured as a PLC (programmable logic controller). The controller 60, which is configured as a PLC, is programmed using a language such as ladder logic to control the coordinated operations of each device, such as molding by the injection molding apparatus 20, removal of the molded product by the robot 70, inspection of the molded product by the inspection apparatus 80, and transportation of the molded product by the movement mechanism 90.

[0026] All of the above-mentioned devices, namely, the injection molding device 20, the material supply device 30, the compressed air pump 31, the dryer 40, the temperature regulator 50, the controller 60, the inspection device 80, the moving mechanism 90, and the power supply unit 100, are all contained within the housing 10.

[0027] The housing 10 is provided with casters 16 at the corners of its bottom surface. Therefore, the injection molding system 1 is configured to be freely movable. In this embodiment, the bottom surface of the housing 10 is provided with bolt-type stoppers 17 adjacent to the casters 16. By using the stoppers 17, the user can fix the injection molding system 1 to the installation location.

[0028] The housing 10 includes a first base 12, a second base 15, and a third base 18. The first base 12 is a base located at the top of the housing 10. The second base 15 is a base located lower than the first base 12. The third base 18 is a base located lower than the second base 15.

[0029] In this embodiment, an injection molding device 20, a robot 70, an inspection device 80, and a movement mechanism 90 are arranged on the first base 12. A controller 60 is arranged on the second base 15. In this embodiment, a power supply unit 100 is also arranged on the second base 15. A material supply device 30, a dryer 40, and a temperature regulator 50 are arranged on the third base 18. In this embodiment, a compressed air pump 31 is also arranged on the third base 18.

[0030] In this embodiment, the first base 12 includes an upper stage 12t and a lower stage 12b located below the upper stage 12t. An injection molding device 20, a robot 70, and an inspection device 80 are disposed in the upper stage 12t. A movement mechanism 90 is disposed in the lower stage 12b. In this embodiment, the placement of the robot 70 in the upper stage 12t means that a base portion supporting the arm of the robot 70 is also disposed therein. Also, as shown in FIG. 2, an opening 19 is formed in an area of ​​the upper stage 12t of the first base 12 on the negative side of the X-axis. In the first base 12, the lower stage 12b is exposed through the opening 19.

[0031] <Configuration of injection molding equipment> The configuration of injection molding apparatus 20 will be described below with reference to FIGS. 3 to 5. FIG. 3 is a perspective view showing an example of the configuration of injection molding apparatus 20. FIG. 4 is a side view of injection molding apparatus 20 in a mold-clamped state in which mold 21 is closed. FIG. 5 is a side view of injection molding apparatus 20 in a mold-opened state in which mold 21 is open. Here, the mold-clamped state refers to a state of injection molding apparatus 20 in which movable mold 21CR is assembled to fixed mold 21CV. In other words, the mold-clamped state refers to a state in which molding material is injected into the cavity in mold 21 and a molded product is molded in mold 21. Therefore, when mold 21 is closed, this means that movable mold 21CR is assembled to fixed mold 21CV. The mold-open state refers to a state in which injection molding apparatus 20 in which movable mold 21CR is separated from fixed mold 21CV. In other words, the mold open state is a state in which the movable mold 21CR is located at the farthest position from the fixed mold 21CV among all possible positions for the movable mold 21CR. Therefore, when the mold 21 is open, it means that the movable mold 21CR is separated from the fixed mold 21CV, that is, the movable mold 21CR is located at that position. For convenience of explanation, this position will be referred to as the separated position below. The state of the injection molding apparatus 20 shown in Figure 3 is a mold clamped state.

[0032] The injection molding apparatus 20 includes a mounting base BS, a fixed mold attachment portion B1, a toggle-type mold clamping mechanism TG, a platen PL, four tie bars (first tie bar TB1 to fourth tie bar TB4), an ejector plate PS1, N ejector pins EP, and a biasing member SP. N may be any integer equal to or greater than 1. The injection molding apparatus 20 may include other members, devices, etc. in addition to the mounting base BS, the fixed mold attachment portion B1, the toggle-type mold clamping mechanism TG, the platen PL, four tie bars (first tie bar TB1 to fourth tie bar TB4), the ejector plate PS1, N ejector pins EP, and the biasing member SP. The injection molding apparatus 20 may also be configured without the mounting base BS. In this case, the injection molding apparatus 20 is mounted directly on, for example, the upper stage 12t of the first base 12.

[0033] The mounting base BS is fixed immovably on the upper stage 12t of the first base 12. The mounting base BS is a base to which the toggle-type mold clamping mechanism TG and the platen PL are attached together with the fixed mold attachment part B1. The mounting base BS may have any configuration as long as it is capable of attaching the fixed mold attachment part B1, the toggle-type mold clamping mechanism TG, and the platen PL. Below, as an example, a case will be described in which the mounting base BS is configured to include two rails to which the fixed mold attachment part B1, the toggle-type mold clamping mechanism TG, and the platen PL can be attached, as shown in FIGS. 3 to 5. Here, in the example shown in FIGS. 3 to 5, the two rails included in the mounting base BS extend parallel to the Y-axis and face each other in a direction parallel to the X-axis. This is because, in this embodiment, the mold clamping direction coincides with the negative direction of the Y-axis.

[0034] The fixed mold mounting portion B1 is a member to which the fixed mold 21CV is attached. The fixed mold mounting portion B1 is fixed so as not to move relative to two rails included in the mounting base BS and is positioned closer to the mold clamping direction than the platen PL. The fixed mold 21CV is attached to the fixed mold mounting portion B1 so that the fixed mold assembly surface, which is assembled with the movable mold 21CR among the surfaces of the fixed mold 21CV, faces the mold opening direction opposite to the mold clamping direction. That is, in this embodiment, the fixed mold 21CV is attached to the fixed mold mounting portion B1 so that the fixed mold assembly surface faces the positive direction of the Y axis. Here, the fixed mold assembly surface facing the mold opening direction means that, among the surfaces included in the fixed mold assembly surface that are perpendicular to the mold clamping direction, the normal line extending from the surface of the fixed mold 21CV on the mold clamping direction side to the fixed mold assembly surface coincides with the mold opening direction.

[0035] The toggle-type mold clamping mechanism TG clamps the fixed mold 21CV and the movable mold 21CR by moving the platen PL in the mold clamping direction, and opens the fixed mold 21CV and the movable mold 21CR by moving the platen PL in the mold opening direction. The toggle-type mold clamping mechanism TG includes, for example, a base B2, a ball screw PS2, a toggle mechanism TGM, and a drive unit MT. The toggle-type mold clamping mechanism TG may include other members, other devices, etc. in addition to the base B2, the ball screw PS2, the toggle mechanism TGM, and the drive unit MT. The toggle-type mold clamping mechanism TG may also be configured without the drive unit MT. In this case, other members, other devices, etc. having the same function as the drive unit MT are externally attached to the toggle-type mold clamping mechanism TG. In the following, as an example, a five-joint double toggle link mold clamping mechanism will be described. The toggle type mold clamping mechanism TG may be a five-node single toggle link type mold clamping mechanism instead of a five-node double toggle link type mold clamping mechanism.

[0036] The base B2 is a member that supports the ball screw PS1 and the toggle mechanism TGM. The base B2 is also referred to as a pressure platen. The base B2 is fixed so as not to move relative to two rails included in the mounting base BS, so that it is positioned closer to the mold opening direction than the platen PL. A flange to which the toggle mechanism TGM is attached is provided on the surface of the base B2 that faces the mold clamping direction.

[0037] The ball screw PS2 is mounted on the base B2 so that its position relative to the fixed mold mounting part B1 does not change and so that it can rotate about its central axis. The ball screw PS2 is supported by the base B2 so that the central axis of the ball screw PS2 extends parallel to the mold clamping direction. A reducer may or may not be provided between the ball screw PS2 and the drive part MT.

[0038] The toggle mechanism TGM includes a crosshead XH, a first connecting rod CN1, a first link L1, a first crank CK1, a second connecting rod CN2, a second link L2, and a second crank CK2.

[0039] The crosshead XH is a member that can move parallel to the mold clamping direction in response to the rotation of the ball screw PS2. For this reason, the crosshead XH has a through-hole formed parallel to the mold clamping direction, the through-hole having an internal thread that meshes with the threads of the ball screw PS2. In the example shown in FIGS. 3 to 5, the crosshead XH is a member that has an overall rectangular parallelepiped shape, but this is not limited to this. In addition, a flange to which the first link L1 is rotatably attached is provided on the upper surface of the crosshead XH. In addition, a flange to which the second link L2 is rotatably attached is provided on the lower surface of the crosshead XH.

[0040] When viewing the injection molding apparatus 20 in the positive direction of the X-axis, the first connecting rod CN1 is a rod-shaped member rotatably supported by the platen PL above the ball screw PS2. More specifically, the first connecting rod CN1 is supported by a first flange F1 provided on the platen PL so that the rotation axis of the first connecting rod CN1 on the platen PL is parallel to the X-axis. Here, the first flange F1 is a flange provided on the surface of the platen PL facing the mold opening direction, and is a flange located above the ball screw PS2.

[0041] The first link L1 is a rod-shaped member rotatably supported by a flange provided on the upper surface of the crosshead XH. More specifically, the first link L1 is supported by the flange so that the rotation axis of the first link L1 on the flange is parallel to the X-axis.

[0042] The first crank CK1 is a member rotatably connected to the base B2, the first connecting rod CN1, and the first link L1. The first crank CK1 is rotatably supported by a flange provided on the base B2. More specifically, the first crank CK1 is rotatably supported by the flange provided above the ball screw PS2. The first crank CK1 rotatably supports the first connecting rod CN1. The first crank CK1 also rotatably supports the first link L1. The rotation axes of the first connecting rod CN1 and the first link L1 on the first crank CK1 are parallel to the X-axis. The rotation axis of the first crank CK1 on the base B2 is also parallel to the X-axis.

[0043] Here, the first connecting rod CN1 and the first crank CK1 constitute two links in a toggle mechanism. The first link L1 is a member that applies force to the connection point of these two links in response to the movement of the crosshead XH. Therefore, the first connecting rod CN1, the first link L1, and the first crank CK1 each constitute a toggle mechanism. The object to which force is applied by this toggle mechanism is the platen PL.

[0044] When viewing the injection molding apparatus 20 in the positive direction of the X-axis, the second connecting rod CN2 is a rod-shaped member rotatably supported by the platen PL below the ball screw PS2. More specifically, the second connecting rod CN2 is supported by a second flange F2 provided on the platen PL so that the rotation axis of the second connecting rod CN2 on the platen PL is parallel to the X-axis. Here, the second flange F2 is a flange provided on the surface of the platen PL facing the mold opening direction, and is a flange located below the ball screw PS2.

[0045] The second link L2 is a rod-shaped member rotatably supported by a flange provided on the underside of the crosshead XH. More specifically, the second link L2 is supported by the flange so that the rotation axis of the second link L2 on the flange is parallel to the X-axis.

[0046] The second crank CK2 is a member rotatably connected to the base B2, the second connecting rod CN2, and the second link L2. The second crank CK2 is rotatably supported by a flange provided on the base B2. More specifically, the second crank CK2 is rotatably supported by the flange provided below the ball screw PS2. The second crank CK2 rotatably supports the second connecting rod CN2. The second crank CK2 also rotatably supports the second link L2. The rotation axes of the second connecting rod CN2 and the second link L2 on the second crank CK2 are parallel to the X-axis. The rotation axis of the second crank CK2 on the base B2 is also parallel to the X-axis.

[0047] Here, the second connecting rod CN2 and the second crank CK2 constitute two links in a toggle mechanism. The second link L2 is a member that applies force to the connection point of these two links in response to the movement of the crosshead XH. Therefore, the second connecting rod CN2, the second link L2, and the second crank CK2 each constitute a toggle mechanism. The object to which force is applied by this toggle mechanism is the platen PL.

[0048] In such a toggle mechanism TGM, the first crank CK1 and the second crank CK2 face each other with the ball screw PS2 in between. Furthermore, in the toggle mechanism TGM, the first crank CK1 is located above the ball screw PS2 when the toggle clamping mechanism TG is viewed from a direction parallel to the central axis of the ball screw PS2. Furthermore, in the toggle mechanism TGM, the second crank CK2 is located below the ball screw PS2 when the toggle clamping mechanism TG is viewed from a direction parallel to the central axis of the ball screw PS2. Furthermore, in the toggle mechanism TGM, the rotation axis of the first connecting rod CN1 in the first crank CK1 approaches the ball screw PS2 in response to movement of the crosshead XH in the mold opening direction, and moves away from the ball screw PS2 in response to movement of the crosshead XH in the mold clamping direction. In addition, in the toggle mechanism TGM, the rotation axis of the second connecting rod CN2 in the second crank CK2 approaches the ball screw PS2 as the crosshead XH moves in the mold opening direction, and moves away from the ball screw PS2 as the crosshead XH moves in the mold closing direction.

[0049] The drive unit MT is an actuator that rotates the ball screw PS2. The drive unit MT drives the crosshead XH by rotating the ball screw PS2. For example, the drive unit MT is a servo motor, but is not limited to this.

[0050] As described above, the toggle-type clamping mechanism TG is a double-toggle-type clamping mechanism having the toggle mechanism TGM. Therefore, when the injection molding apparatus 20 is viewed in the positive direction of the X-axis, the shape of the combination of the first connecting rod CN1, first link L1, and first crank CK1 and the shape of the combination of the second connecting rod CN2, second link L2, and second crank CK2 are symmetrical with respect to the ball screw PS1 as the axis of symmetry.

[0051] The platen PL is a member to which the movable mold 21CR is attached so as to face the fixed mold 21CV in the mold clamping direction. The platen PL is attached to two rails included in the mounting base BS so as to be slidable parallel to the mold clamping direction between the fixed mold attachment part B1 and the toggle-type mold clamping mechanism TG. As described above, the platen PL is connected to each of the first connecting rod CN1 and the second connecting rod CN2 of the toggle-type mold clamping mechanism TG, and moves parallel to the mold clamping direction relative to the fixed mold attachment part B1 in accordance with the movement of the crosshead XH of the toggle-type mold clamping mechanism TG. As a result, the toggle-type mold clamping mechanism TG can clamp the fixed mold 21CV and the movable mold 21CR by moving the platen PL in the mold clamping direction, and can open the fixed mold 21CV and the movable mold 21CR by moving the platen PL in the mold opening direction. In other words, this allows the toggle-type clamping mechanism TG to assemble the movable mold 21CR to the fixed mold 21CV to perform injection molding and apply pressure to the molding material injected into the cavity between the movable mold 21CR and the fixed mold 21CV.

[0052] The platen PL has a recess recessed toward the mold opening direction. The movable mold 21CR is fixed to close the recess and not move relative to the platen PL. The movable mold 21CR is fixed to the platen PL so that the surface of the movable mold 21CR facing the fixed mold 21CV faces the mold clamping direction. Therefore, when the platen PL moves in the mold clamping direction in accordance with the movement of the crosshead XH of the toggle-type mold clamping mechanism TG, the movable mold 21CR approaches the fixed mold 21CV together with the platen PL and is assembled to the fixed mold 21CV. When the platen PL moves in the mold opening direction in accordance with the movement of the crosshead XH of the toggle-type mold clamping mechanism TG, the movable mold 21CR moves away from the fixed mold 21CV together with the platen PL to the aforementioned separated position. The position of the platen PL when the movable mold 21CR is in the separated position may be expressed as the position closest to the mold opening direction among the positions to which the platen PL can move.

[0053] Furthermore, a through-hole through which the ball screw PS2 can be inserted is formed on the surface of the platen PL facing the mold opening direction, leading to the recess in the platen PL that is blocked by the movable mold 21CR when the injection molding apparatus 20 changes from the mold clamping state to the mold open state. When the injection molding apparatus 20 is in the mold clamping state, the ball screw PS2 is not inserted through the through-hole. This is because, when the injection molding apparatus 20 changes from the mold open state to the mold clamping state, the platen PL moves further toward the mold clamping direction than the tip of the ball screw PS2. For this reason, in the example shown in FIG. 4, a gap exists between the platen PL and the tip of the ball screw PS2. When the injection molding apparatus 20 is in the mold open state, the ball screw PS2 is inserted through the through-hole and is in contact with the ejector plate PS1 that is attached to the recess in the platen PL.

[0054] The first tie bar TB1 and the second tie bar TB2 are shafts supported parallel to the central axis of the ball screw PS2 by the fixed mold mounting part B1 and the base B2 of the toggle-type mold clamping mechanism TG, respectively, and are located above the ball screw PS2. Furthermore, the first tie bar TB1 overlaps with the second tie bar TB2 when the first tie bar TB1 and the second tie bar TB2 are viewed from a direction parallel to the rotation axis of the first connecting rod CN1 in the first flange F1.

[0055] The third tie bar TB3 and the fourth tie bar TB4 are shafts that are supported parallel to the central axis of the ball screw PS2 by the fixed mold mounting part B1 and the base B2 of the toggle-type mold clamping mechanism TG, respectively, and are located below the ball screw PS2. Furthermore, the third tie bar TB3 overlaps with the fourth tie bar TB4 when the third tie bar TB3 and the fourth tie bar TB4 are viewed from a direction parallel to the rotation axis of the second connecting rod CN2 at the second flange F2.

[0056] Here, the platen PL is supported by four tie bars, namely, a first tie bar TB1, a second tie bar TB2, a third tie bar TB3, and a fourth tie bar TB4, so as to be slidable parallel to the mold clamping direction. In other words, these four tie bars, together with the mounting base BS, are members that support the platen PL. In other words, the mounting base BS and these four tie bars support the platen PL. In the example shown in FIGS. 3 to 5, when the first flange F1 and the second tie bar TB1 and TB2 are viewed from a direction parallel to the rotation axis of the first connecting rod CN1 at the first flange F1, the first flange F1 overlaps with the first tie bar TB1 and the second tie bar TB2, respectively. In addition, in this example, when the second flange F2 and the third tie bar TB3 and the fourth tie bar TB4 are viewed from a direction parallel to the rotation axis of the second connecting rod CN2 at the second flange F2, the second flange F2 overlaps with the third tie bar TB3 and the fourth tie bar TB4, respectively.

[0057] The ejector plate PS1 is a plate-shaped member provided on the platen PL so as to be movable parallel to the mold clamping direction relative to the platen PL within the recess of the platen PL. Note that instead of being provided within the recess of the platen PL, the ejector plate PS1 may be provided outside the recess of the platen PL. The ejector plate PS1 supports N ejector pins EP.

[0058] Here, each of the N ejector pins EP is a rod-shaped member slidably inserted into one of N through holes formed in the movable mold 21CR parallel to the mold clamping direction. That is, the movable mold 21CR has a through hole through which each of the N ejector pins EP passes. Each of the N through holes formed in the movable mold 21CR is formed in the movable mold 21CR so as to connect to the surface of the movable mold 21CR on the mold clamping direction side. As a result, each of the N ejector pins EP moves in the mold clamping direction relative to the movable mold 21CR, thereby being able to push a molded product molded in a cavity between the fixed mold 21CV and the movable mold 21CR out of the movable mold 21CR when the injection molding apparatus 20 is in the mold open state.

[0059] As shown in FIG. 4, when the ejector plate PS1 is positioned furthest in the mold opening direction within the recess of the platen PL, i.e., when the injection molding apparatus 20 is in the mold clamping state, the tips of the N ejector pins EP are positioned within the movable mold 21CR so as to block the through-holes formed in the movable mold 21CR. This allows the injection molding apparatus 20 to prevent the molding material injected into the cavity between the fixed mold 21CV and the movable mold 21CR from leaking out through the N through-holes formed in the movable mold 21CR. On the other hand, as shown in FIG. 5, when the ejector plate PS1 is positioned furthest in the mold opening direction within the recess of the platen PL, i.e., when the injection molding apparatus 20 is in the mold open state, the tips of the N ejector pins EP protrude in the mold clamping direction from the surface of the movable mold 21CR facing the mold clamping direction. This allows each of the multiple ejector pins EP to push the molded product out of the movable mold 21CR after injection molding.

[0060] Here, in the recess of the platen PL, a biasing member SP is provided between the ejector plate PS1 and the movable mold 21CR to bias the ejector plate PS1 in the mold opening direction so as to move the ejector plate PS1 away from the movable mold 21CR. The biasing member SP is, for example, a spring, but is not limited to this. In the example shown in FIGS. 4 and 5, multiple biasing members SP are provided between the ejector plate PS1 and the movable mold 21CR. This allows the injection molding apparatus 20 to position the tips of the N ejector pins EP within the through-holes formed in the movable mold 21CR as long as the ejector plate PS1 is not moved in the mold clamping direction relative to the platen PL by being pushed in the mold clamping direction.

[0061] As mentioned above, a through-hole through which the ball screw PS2 is inserted is formed in the surface of the platen PL facing the mold opening direction. Therefore, as the state of the injection molding apparatus 20 changes from the mold clamping state to the mold opening state, the ejector plate PS1 in the recess of the platen PL approaches the ball screw PS2 and is consequently pushed in the mold clamping direction by the ball screw PS2. That is, in the example shown in FIGS. 3 to 5 , the ball screw PS2 functions as an ejector member that pushes a molded product out of the movable mold 21CR in response to movement of the movable mold 21CR in the mold opening direction after injection molding is performed between the fixed mold 21CV and the movable mold 21CR. This means that the injection molding apparatus 20 can eject a molded product from the movable mold 21CR without having to include an actuator for moving each of the N ejector pins EP back and forth in the mold clamping direction. That is, the injection molding apparatus 20 can simplify its control system. Furthermore, because the injection molding apparatus 20 pushes a molded product out of the movable mold 21CR while the toggle-type mold clamping mechanism TG is opening the molds, the cycle time for molding the molded product can be shortened compared to when the toggle-type mold clamping mechanism TG opens the molds and then pushes the molded product out of the movable mold 21CR. The length of the ball screw PS2 in the mold clamping direction is adjusted so that each of the N ejector pins EP can push the molded product out of the movable mold 21CR, while the ejector plate PS1 does not push the movable mold 21CR out of the platen PL. In the example shown in FIG. 5, when the injection molding apparatus 20 is in the mold open state, the ejector plate PS1 is in contact with the movable mold 21CR. However, this is merely an example, and the ejector plate PS1 may be separated from the movable mold 21CR even when the injection molding apparatus 20 is in the mold open state. The N ejector pins EP may also be integral with the ball screw PS2. In this case, there is no need to provide the ejector plate PS1 in the injection molding device 20. Also, the injection molding device 20 may be configured so that the molded product is pushed out of the movable mold 21CR by the ball screw PS2 itself.In this case, instead of the through holes through which the N ejector pins EP are inserted, the movable mold 21CR is formed with a through hole through which the ball screw PS2 is inserted. In this case, the injection molding apparatus 20 does not need to be equipped with the N ejector pins EP together with the ejector plate PS1. The injection molding apparatus 20 may also be configured with a push-out member separate from the ball screw PS2. In this case, the push-out member is provided so that its position relative to the fixed mold attachment portion B1 does not change, like the ball screw PS2, and moves the ejector plate PS1 in the mold clamping direction in response to mold opening by the toggle-type mold clamping mechanism TG, thereby pushing the molded product out of the movable mold 21CR. When the injection molding apparatus 20 is equipped with the push-out member, the push-out member is supported by the base B2, for example, like the ball screw PS2, but this is not limited to this.

[0062] Here, the injection molding apparatus 20 described above may be configured such that when the platen PL is located at the position furthest in the mold opening direction among the positions to which the platen PL can be moved, i.e., when the movable mold 21CR is located at the separated position, a part of the toggle mechanism TGM overlaps with the crosshead XH when viewed from a direction parallel to the central axis of the ball screw PS2. FIG. 6 is a perspective view showing an example of the state around the crosshead XH when the movable mold 21CR is located at the separated position. FIG. 7 is a front view of the crosshead XH shown in FIG. 6. The position furthest in the mold opening direction among the positions to which the platen PL can be moved may be a position determined structurally or may be a position determined by control.

[0063] When the platen PL moves in the mold opening direction, the rotation axis of the first connecting rod CN1 of the first crank CK1 moves downward to approach the ball screw PS2. Therefore, when the platen PL moves in the mold opening direction, the lower end of the first crank CK1 also moves downward to approach the ball screw PS2. In the example shown in FIGS. 6 and 7, the lower end of the first crank CK1, which approaches the ball screw PS2 in this manner, overlaps with the crosshead XH when the movable mold 21CR is positioned at the separated position, when the crosshead XH is viewed from a direction parallel to the center axis of the ball screw PS2. Therefore, in this example, the position of the lower end of the first crank CK1 in the direction of gravity is located at a distance h lower than the position of the upper surface of the crosshead XH in the direction of gravity. However, even in this case, the first crank CK1 is separated from the ball screw PS2. This is to prevent the first crank CK1 from deforming the ball screw PS2 or causing wear on the ball screw PS2.

[0064] Furthermore, when the platen PL moves in the mold opening direction, the rotation axis of the second connecting rod CN2 of the second crank CK2 moves upward to approach the ball screw PS2. Therefore, when the platen PL moves in the mold opening direction, the upper end of the second crank CK2 also moves upward to approach the ball screw PS2. In the example shown in FIGS. 6 and 7, the upper end of the second crank CK2, which approaches the ball screw PS2 in this manner, overlaps with the crosshead XH when the movable mold 21CR is positioned at the separated position, when the crosshead XH is viewed from a direction parallel to the center axis of the ball screw PS2. Therefore, in this example, the position of the upper end of the second crank CK2 in the direction of gravity is located at a distance h higher than the position of the lower surface of the crosshead XH in the direction of gravity. However, even in this case, the second crank CK2 is separated from the ball screw PS2. This is to prevent the second crank CK2 from deforming the ball screw PS2 or causing wear on the ball screw PS2.

[0065] When the movable mold 21CR is positioned at the separated position, the lower end of the first crank CK1 and the upper end of the second crank CK2 overlap the crosshead XH when viewed from a direction parallel to the central axis of the ball screw PS2. This means that the platen PL can be moved closer to the base B2 of the toggle-type mold clamping mechanism TG than when the lower and upper ends do not overlap the crosshead XH. This means that the movable mold 21CR attached to the platen PL can move a longer distance without changing the distance between the fixed mold mounting portion B1 and the base B2. This allows the injection molding apparatus 20 to be shorter in the direction of the central axis of the ball screw PS2, i.e., in the mold clamping direction. This is useful because it leads to a more compact injection molding apparatus 20.

[0066] When the movable die 21CR is located at the separated position, the lower end of the first crank CK1 and the upper end of the second crank CK2 overlap with the crosshead XH when viewed from a direction parallel to the center axis of the ball screw PS2. This may be replaced with the lower end of the first connecting rod CN1 and the upper end of the second connecting rod CN2 overlapping with the crosshead XH when viewed from that direction. Also, when the movable die 21CR is located at the separated position, the lower end of the first crank CK1 and the upper end of the second crank CK2 overlap with the crosshead XH when viewed from a direction parallel to the center axis of the ball screw PS2. This may be replaced with the lower end of the first link L1 and the upper end of the second link L2 overlapping with the crosshead XH when viewed from that direction.

[0067] 6 and 7, when the movable die 21CR is not positioned at the separated position, the lower end of the first crank CK1 and the upper end of the second crank CK2 do not need to overlap with the crosshead XH in the direction parallel to the central axis of the ball screw PS2, as shown in Fig. 8. Fig. 8 is a diagram showing an example of the state around the crosshead XH when the movable die 21CR is not positioned at the separated position.

[0068] In the example shown in FIGS. 6 to 8, the crosshead XH is supported by two shafts, shaft AX1 and shaft AX2. That is, in this example, the toggle-type clamping mechanism TG includes shaft AX1 and shaft AX2 for supporting the crosshead XH. These two shafts are supported by a base B2. These two shafts face each other across the ball screw PS2. Therefore, by including these two shafts in the toggle-type clamping mechanism TG, the injection molding apparatus 20 can prevent the crosshead XH from rotating around the ball screw PS2 in response to the rotation of the ball screw PS2 by the drive unit MT. The injection molding apparatus 20 may be configured without either shaft AX1 or shaft AX2. Even in this case, the injection molding apparatus 20 can prevent the crosshead XH from rotating around the ball screw PS2 in response to the rotation of the ball screw PS2 by the drive unit MT. The shaft AX1 and the shaft AX2 are examples of two shafts included in the rotation suppressing unit. Furthermore, if there is no need to suppress rotation of the crosshead XH around the ball screw PS2, the injection molding apparatus 20 may not include these two shafts. Furthermore, instead of the shaft AX1 and the shaft AX2, the injection molding apparatus 20 may include another member that suppresses rotation of the crosshead XH in response to rotation of the ball screw PS2. This other member may be, for example, a jig that holds down at least one of the upper surface and the lower surface of the crosshead XH to prevent the crosshead XH from rotating. The jig is supported, for example, by the base B2. This jig is also an example of a rotation suppressing unit.

[0069] In the injection molding apparatus 20 described above, the first flange F1 of the platen PL overlaps with the first tie bar TB1 and the second tie bar TB2 when viewed from a direction parallel to the rotation axis of the first connecting rod CN1 of the first flange F1. Furthermore, in the injection molding apparatus 20 described above, the second flange F2 of the platen PL overlaps with the third tie bar TB3 when viewed from a direction parallel to the rotation axis of the second connecting rod CN2 of the second flange F2. In this case, in the injection molding apparatus 20, the movable mold 21CR attached to the platen PL may bend when clamping is performed using the toggle-type clamping mechanism TG, as shown in FIG. 9 . FIG. 9 is a diagram illustrating the bending of the movable mold 21CR attached to the platen PL when clamping is performed using the toggle-type clamping mechanism TG. When clamping the mold, the toggle-type mold clamping mechanism TG applies a force to the platen PL in the directions indicated by arrows A1 and A2 in FIG. 9 . Specifically, the first connecting rod CN1 of the toggle-type mold clamping mechanism TG applies a force to the upper part of the platen PL in the direction indicated by arrow A1. Here, the direction indicated by arrow A1 is approximately parallel to the mold clamping direction. Therefore, the force applied to the platen PL by the first connecting rod CN1 in this case is applied to the upper part of the movable mold 21CR attached to the platen PL. On the other hand, the second connecting rod CN2 of the toggle-type mold clamping mechanism TG applies a force to the lower part of the platen PL in the direction indicated by arrow A2. Here, the direction indicated by arrow A2 is approximately parallel to the mold clamping direction. Therefore, the force applied to the platen PL by the second connecting rod CN2 in this case is applied to the lower part of the movable mold 21CR attached to the platen PL. Furthermore, when the molds are being clamped, a force is applied to the center of the movable mold 21CR in the direction indicated by arrow A3 due to the pressure of the molding material injected into the cavity between the fixed mold 21CV and the movable mold 21CR, which is roughly parallel to the mold opening direction.When these three forces are applied to the movable mold 21CR, the movable mold 21CR may bend in a shape such that the center of the movable mold 21CR is recessed toward the mold opening direction, i.e., in a shape like the arc CL shown in FIG. 9, depending on the positional relationship of the force application points. This bending may be visible to the naked eye, but may also be so slight that it is not visible to the naked eye. When such bending occurs, the toggle-type clamping mechanism TG may not clamp the fixed mold 21CV and the movable mold 21CR uniformly. This undesirably leads to a decrease in the molding accuracy of the molded product formed by injection molding using the mold 21.

[0070] Therefore, in the injection molding apparatus 20, the first flange F1 and the second flange F2 may each be configured to be closer to the ball screw PS2 than in the example shown in FIG. 9, as shown in FIG. 10. FIG. 10 is a side view showing a first modified example of the configuration of the injection molding apparatus 20. In the example shown in FIG. 10, when the first flange F1 is viewed from a direction parallel to the rotation axis of the first connecting rod CN1 of the first flange F1, the first flange F1 does not overlap with the first tie bar TB1 or the second tie bar TB2 and is located below the first tie bar TB1 and the second tie bar TB2. In this case, when the toggle-type mold clamping mechanism TG clamps the mold, the first connecting rod CN1 applies force to the platen PL in the direction indicated by arrow A4 in FIG. 10. Here, the direction indicated by arrow A4 is inclined with respect to the mold clamping direction so as to approach the central axis of the ball screw PS2 from above the ball screw PS2. That is, in this case, when mold clamping is performed by the toggle-type mold clamping mechanism TG, the first connecting rod CN1 applies force toward a position closer to the center of the platen PL than the position of the first flange F1 shown in FIG. 9. Meanwhile, in this example, when the second flange F2 is viewed from a direction parallel to the rotation axis of the second connecting rod CN2 at the second flange F2, the second flange F2 does not overlap with the third tie bar TB3 or the fourth tie bar TB4 and is located above the third tie bar TB3 and the fourth tie bar TB4. In this case, when mold clamping is performed by the toggle-type mold clamping mechanism TG, the second connecting rod CN2 applies force to the platen PL in the direction indicated by arrow A5 shown in FIG. 10. Here, the direction indicated by arrow A5 is a direction inclined with respect to the mold clamping direction so as to approach the central axis of the ball screw PS2 from below the ball screw PS2. That is, in this case, when mold clamping is performed by the toggle-type mold clamping mechanism TG, the second connecting rod CN2 applies force toward a position closer to the center of the platen PL than the position of the second flange F2 shown in Fig. 9. As a result, the forces applied to the platen PL by the first connecting rod CN1 and the second connecting rod CN2 respectively suppress the bending of the vicinity of the center of the movable mold 21CR toward the mold opening direction relative to the upper and lower parts of the movable mold 21CR.That is, by positioning the first flange F1 and the second flange F2 close to the ball screw PS2, the injection molding apparatus 20 can uniformly clamp the fixed mold 21CV and the movable mold 21CR using the toggle-type clamping mechanism TG. In other words, by positioning the first flange F1 and the second flange F2 close to the ball screw PS2, the injection molding apparatus 20 can prevent a decrease in the molding accuracy of the molded product formed by injection molding using the mold 21. In yet other words, by positioning the first flange F1 and the second flange F2 close to the ball screw PS2, the injection molding apparatus 20 can increase the pressure at the center of the mold 21 when clamping, thereby preventing deformation of the mold 21 when resin filling pressure is applied. This is useful because it leads to maintenance of the mold 21 and improved molding quality.

[0071] Furthermore, in the injection molding apparatus 20 described above, the drive unit MT of the toggle clamping mechanism TG is provided adjacent to the toggle mechanism TGM on the mold opening direction side. However, as shown in FIG. 11 , the drive unit MT may be configured to overlap with the toggle mechanism TGM in a direction perpendicular to the center axis of the ball screw PS2. FIG. 11 is a top view showing an example of an injection molding system 1 in which the drive unit MT of the toggle clamping mechanism TG overlaps with the toggle mechanism TGM in a direction perpendicular to the center axis of the ball screw PS2. In the example shown in FIG. 11 , the drive unit MT is provided adjacent to the toggle mechanism TGM on the positive side of the Y-axis. In this case, the drive unit MT overlaps with the toggle mechanism TGM in a direction perpendicular to the center axis of the ball screw PS2. That is, in this example, the positive direction is an example of a direction perpendicular to the center axis of the ball screw PS2. This allows the injection molding apparatus 20 to have a shorter length in the mold clamping direction than when the drive unit MT is provided on the mold opening direction side of the toggle mechanism TGM. This is useful because it leads to a more compact injection molding apparatus 20. It is also useful because it leads to more effective use of dead space. The drive unit MT may be provided adjacent to the toggle mechanism TGM on the negative side of the Y-axis, adjacent to the toggle mechanism TGM on the positive side of the Z-axis, adjacent to the toggle mechanism TGM on the negative side of the Z-axis, or adjacent to the toggle mechanism TGM on another side perpendicular to the central axis of the ball screw PS2. Furthermore, when the drive unit MT overlaps with the toggle mechanism TGM in the direction perpendicular to the central axis of the ball screw PS2, the drive unit MT rotates the ball screw PS2 via, for example, a belt mechanism or the like.

[0072] In the injection molding apparatus 20 described above, the four tie bars, the first tie bar TB1, the second tie bar TB2, the third tie bar TB3, and the fourth tie bar TB4, all have the same diameter. As shown in FIG. 12 , the mold opening direction end of each of these four tie bars is externally threaded with a thread diameter equal to the diameter of the four tie bars. FIG. 12 is a diagram showing an example of the configuration of the first tie bar TB1, one of the four tie bars included in the injection molding apparatus 20. In the example shown in FIG. 12 , one of the two ends of the first tie bar TB1 is externally threaded with a thread diameter equal to the diameter of the first tie bar TB1. This improves the ease of processing the first tie bar TB1. This is useful because it reduces the time required to manufacture the entire injection molding apparatus 20. Furthermore, this eliminates the need to provide a straight portion in the externally threaded portion of the first tie bar TB1, thereby improving the ease of assembly when assembling a nut to the first tie bar TB1. The same applies to each of the second tie bar TB2 to the fourth tie bar TB4. Note that Fig. 13 is a side view showing an example of injection molding apparatus 20 in which each of the first tie bar TB1 to the fourth tie bar TB4 is attached to base B2 of the toggle-type mold clamping mechanism TG with double nuts. Fig. 14 is a perspective view of injection molding apparatus 20 shown in Fig. 13.

[0073] Here, when the injection molding apparatus 20 is equipped with four tie bars as shown in FIG. 12, mold thickness adjustment can be performed smoothly. FIG. 15 is a perspective view showing an example of the injection molding apparatus 20 when a mold thickness adjustment mechanism is attached to the base B2. FIG. 16 is a rear view of the injection molding apparatus 20 shown in FIG. 15. The gear trains shown in FIGS. 15 and 16 are gear trains included in the mold pressure adjustment mechanism. In the example shown in FIGS. 15 and 16, nuts formed integrally with gears included in the gear trains are attached to each of the first tie bar TB1 to the fourth tie bar TB4. These nuts are threadedly engaged with male threads formed on each of the first tie bar TB1 to the fourth tie bar TB4. The mold pressure adjustment mechanism attached to the base B2 in FIGS. 15 and 16 is a well-known mechanism, so further detailed description will be omitted.

[0074] 12, an operator operating the injection molding apparatus 20 can adjust the mold pressure while maintaining the parallelism of the platens PL. This allows the operator to generate a stable clamping pressure using the toggle-type clamping mechanism TG in the injection molding apparatus 20. As a result, the injection molding apparatus 20 can increase both the clamping duration and the clamping pressure.

[0075] The above-described contents may be combined in any manner.

[0076] <Additional Notes> [1] an injection molding system including an injection molding apparatus that performs injection molding of a molded product using a mold consisting of a fixed mold and a movable mold assembled to the fixed mold, wherein the injection molding apparatus comprises: a fixed mold mounting portion to which the fixed mold is attached; a platen to which the movable mold is attached so as to face the fixed mold in a predetermined mold clamping direction and which is movable parallel to the mold clamping direction; a toggle-type mold clamping mechanism that clamps the fixed mold and the movable mold together by moving the platen toward the mold clamping direction and opens the fixed mold and the movable mold together by moving the platen toward a mold opening direction opposite the mold clamping direction; and an extrusion member that is arranged so that its position relative to the fixed mold mounting portion does not change and that extrudes the molded product from the movable mold in response to the mold opening by the toggle-type mold clamping mechanism. [2] 1. The injection molding system according to claim 1, further comprising: N ejector pins slidably inserted into N through holes formed in the movable mold parallel to the mold clamping direction, where N is an integer greater than or equal to 1; the toggle-type mold clamping mechanism includes a base, a ball screw supported on the base so as to be rotatable about a central axis so that its position relative to the fixed mold mounting portion does not change, and a crosshead movable parallel to the mold clamping direction in accordance with rotation of the ball screw; a toggle mechanism that moves the platen parallel to the mold clamping direction in accordance with movement of the crosshead; and a drive unit that rotates the ball screw; and the ejection member is the ball screw, and the molded product is pushed out of the movable mold by pushing the N ejector pins in the mold clamping direction relative to the movable mold in accordance with mold opening by the toggle-type mold clamping mechanism. [3] [2] The injection molding system according to [2], comprising: an ejector plate that faces the movable mold in the mold clamping direction, is movable parallel to the mold clamping direction relative to the platen, and supports the N ejector pins; and a biasing member that biases the ejector plate in the mold opening direction so as to move the ejector plate away from the movable mold, wherein the ejection member pushes the N ejector pins in the mold clamping direction via the ejector plate in response to mold opening by the toggle-type mold clamping mechanism, thereby pushing the molded product out of the movable mold. [4] The toggle mechanism includes a first connecting rod rotatably supported by the platen, a first link rotatably supported by the crosshead, a first crank rotatably connected to each of the base, the first connecting rod, and the first link, a second connecting rod rotatably supported by the platen, a second link rotatably supported by the crosshead, and a second crank rotatably connected to each of the base, the second connecting rod, and the second link, the first crank and the second crank facing each other with the ball screw interposed therebetween, and the first crank is configured to rotate relative to the toggle mechanism when viewed from a direction parallel to the central axis. the second crank is located above the ball screw when the toggle-type mold clamping mechanism is viewed from a direction parallel to the central axis, the second crank is located below the ball screw when the toggle-type mold clamping mechanism is viewed from a direction parallel to the central axis, the rotation axis of the first connecting rod in the first crank approaches the ball screw as the crosshead moves in the mold opening direction and moves away from the ball screw as the crosshead moves in the mold clamping direction, and the rotation axis of the second connecting rod in the second crank approaches the ball screw as the crosshead moves in the mold opening direction and moves away from the ball screw as the crosshead moves in the mold clamping direction. [5] [4] The injection molding system described in [4], wherein when the platen is positioned at the position furthest to the mold opening direction among the positions to which the platen can move, when the crosshead is viewed from a direction parallel to the central axis, a portion of the toggle mechanism overlaps with the crosshead. [6] [5] The injection molding system described in [5], wherein when the crosshead is viewed from a direction parallel to the central axis when the platen is positioned at the position furthest to the mold opening direction among the positions to which the platen can be moved, the lower end of the first crank overlaps with the crosshead and is spaced apart from the ball screw, and when the crosshead is viewed from a direction parallel to the central axis when the platen is positioned at the position furthest to the mold opening direction among the positions to which the platen can be moved, the upper end of the second crank overlaps with the crosshead and is spaced apart from the ball screw. [7] The injection molding system according to any one of [4] to [6], comprising: a first tie bar and a second tie bar that are supported by the fixed mold mounting portion and the base, respectively, parallel to the central axis and positioned above the ball screw; and a third tie bar and a fourth tie bar that are supported by the fixed mold mounting portion and the base, respectively, parallel to the central axis and positioned below the ball screw. [8] The platen is supported by four tie bars, namely the first tie bar, the second tie bar, the third tie bar, and the fourth tie bar, so as to be slidable in parallel to the mold clamping direction, and the platen includes a first flange that rotatably supports the first connecting rod and a second flange that rotatably supports the second connecting rod, and the first tie bar overlaps with the second tie bar when the first tie bar and the second tie bar are viewed from a direction parallel to a rotation axis of the first connecting rod at the first flange, and the first flange is viewed from a direction parallel to the rotation axis of the first connecting rod at the first flange. the third tie bar does not overlap with the first tie bar or the second tie bar and is located below the first tie bar or the second tie bar when viewed from a direction parallel to the rotation axis of the second connecting rod at the second flange, the third tie bar overlaps with the fourth tie bar when viewed from a direction parallel to the rotation axis of the second connecting rod at the second flange, and the second flange does not overlap with the third tie bar or the fourth tie bar and is located above the third tie bar or the fourth tie bar when viewed from a direction parallel to the rotation axis of the second connecting rod at the second flange. [9] [7] or [8], wherein the diameters of the four tie bars, the first tie bar, the second tie bar, the third tie bar, and the fourth tie bar, are the same, and the end of each of the four tie bars on the mold opening direction side is provided with a male screw thread having the same diameter as the diameter of each of the four tie bars.

[10] An injection molding system according to any one of [2] to [9], comprising a rotation suppression unit that suppresses the crosshead from rotating in response to the rotation of the ball screw.

[11]

[10] An injection molding system as described in

[10] , wherein the rotation suppression unit has two shafts extending parallel to the axial direction of the ball screw, the two shafts are supported by the base and face each other across the ball screw, and the crosshead penetrates the crosshead and is supported by the two shafts when the crosshead is viewed from a direction parallel to the central axis.

[12] The injection molding system according to any one of [2] to

[11] , wherein the drive unit overlaps with the toggle mechanism in a direction perpendicular to the central axis.

[13] a toggle-type clamping mechanism that clamps the fixed mold and the movable mold together by moving the platen in a mold opening direction opposite the clamping direction, and opens the fixed mold and the movable mold together by moving the platen in a mold opening direction opposite the clamping direction; and a pusher member that is arranged so that its position relative to the fixed mold attaching part does not change. The method for extruding a molded product comprises: an injection molding apparatus that performs injection molding of a molded product using a mold consisting of a fixed mold and a movable mold assembled to the fixed mold; a fixed mold mounting part to which the fixed mold is attached; a platen to which the movable mold is attached so as to face the fixed mold in a predetermined mold clamping direction and that is movable parallel to the mold clamping direction; a toggle-type clamping mechanism that clamps the fixed mold and the movable mold together by moving the platen in the mold clamping direction, and opens the fixed mold and the movable mold together by moving the platen in a mold opening direction opposite the mold clamping direction; and a pusher member that is arranged so that its position relative to the fixed mold attaching part does not change.

[0077] The embodiments of this disclosure have been described in detail above with reference to the drawings, but the specific configuration is not limited to this embodiment, and may be changed, substituted, deleted, etc. as long as it does not deviate from the gist of this disclosure. [Explanation of symbols]

[0078] 1...injection molding system, 10...casing, 11...side cover, 12...first base, 12b...lower section, 12t...upper section, 13...upper cover, 14...door, 15...second base, 16...caster, 17...stopper, 18...third base, 19...opening, 20...injection molding device, 21...mold, 21CR...movable mold, 21CV...fixed mold, 22...hopper, 23...piping, 30...material supply device, 31...compressed air pump, 40...dryer, 50...temperature controller, 60...controller, 70...robot, 80...inspection device, 81...camera, 82...conveyor mechanism, 90...moving mechanism, 91...tray, 100...power supply unit, AX1, AX2... Shaft, B1...Fixed mold mounting part, B2...Base, BS...Mounting base, CK1...1st crank, CK2...2nd crank, CL...Arc, CN1...1st connecting rod, CN2...2nd connecting rod, EP...Ejector pin, F1...1st flange, F2...2nd flange, L1...1st link, L2...2nd link, MT...Driver, PL...Platen, PS1...Ejector plate, SP...Biasing member, TB1...1st tie bar, TB2...2nd tie bar, TB3...3rd tie bar, TB4...4th tie bar, TC...3D coordinate system, TG...Toggle clamping mechanism, TGM...Toggle mechanism, XH...Crosshead

Claims

1. An injection molding system including an injection molding apparatus that performs injection molding of a molded product using a mold that is composed of a fixed mold and a movable mold that is assembled to the fixed mold, The injection molding apparatus a fixed mold mounting portion to which the fixed mold is attached; a platen to which the movable mold is attached so as to face the fixed mold in a predetermined mold clamping direction and which is movable in parallel with the mold clamping direction; a toggle-type mold clamping mechanism that clamps the fixed mold and the movable mold together by moving the platen in the mold clamping direction, and opens the fixed mold and the movable mold together by moving the platen in a mold opening direction opposite to the mold clamping direction; an extrusion member that is provided so that its position relative to the fixed mold attachment portion does not change and that extrudes the molded product from the movable mold in response to the mold opening by the toggle-type mold clamping mechanism; An injection molding system comprising:

2. the N ejector pins being slidably inserted into N through holes formed in the movable mold in parallel with the mold clamping direction, N is an integer of 1 or more, The toggle-type mold clamping mechanism includes: The base and a ball screw supported by the base so as to be rotatable about a central axis and so as not to change its position relative to the fixed mounting portion; a toggle mechanism including a crosshead movable parallel to the mold clamping direction in response to rotation of the ball screw, the toggle mechanism moving the platen parallel to the mold clamping direction in response to movement of the crosshead; a drive unit that rotates the ball screw; Equipped with the ejection member is the ball screw, and pushes the N ejector pins in the mold clamping direction relative to the movable mold in response to the mold opening by the toggle-type mold clamping mechanism, thereby pushing the molded product out of the movable mold. The injection molding system of claim 1 .

3. an ejector plate that faces the movable mold in the mold clamping direction, is movable parallel to the mold clamping direction relative to the platen, and supports the N ejector pins; an urging member that urges the ejector plate in the mold opening direction so that the ejector plate moves away from the movable mold; Equipped with the ejection member pushes the N ejector pins in the mold clamping direction via the ejector plate in response to the mold opening by the toggle-type mold clamping mechanism, thereby pushing the molded product out of the movable mold. The injection molding system of claim 2 .

4. The toggle mechanism includes: a first connecting rod rotatably supported by the platen; a first link rotatably supported by the crosshead; a first crank rotatably connected to the base, the first connecting rod, and the first link; a second connecting rod rotatably supported by the platen; a second link rotatably supported by the crosshead; a second crank rotatably connected to the base, the second connecting rod, and the second link; Equipped with the first crank and the second crank face each other with the ball screw interposed therebetween, the first crank is located above the ball screw when the toggle-type mold clamping mechanism is viewed from a direction parallel to the central axis, the second crank is located below the ball screw when the toggle-type mold clamping mechanism is viewed from a direction parallel to the central axis, a rotation axis of the first connecting rod in the first crank approaches the ball screw in response to movement of the crosshead in the mold opening direction and moves away from the ball screw in response to movement of the crosshead in the mold clamping direction, a rotation axis of the second connecting rod in the second crank approaches the ball screw in response to movement of the crosshead in the mold opening direction and moves away from the ball screw in response to movement of the crosshead in the mold clamping direction; The injection molding system of claim 2 .

5. When the platen is positioned at a position furthest to the mold opening direction among the positions to which the platen can be moved, a part of the toggle mechanism overlaps with the crosshead when the crosshead is viewed from a direction parallel to the central axis.

5. The injection molding system of claim 4.

6. when the crosshead is viewed in a direction parallel to the central axis when the platen is positioned at a position furthest to the mold opening direction among positions to which the platen can be moved, a lower end of the first crank overlaps with the crosshead and is spaced apart from the ball screw; when the platen is positioned at a position furthest to the mold opening direction among the positions to which the platen can be moved, an upper end of the second crank overlaps with the crosshead and is spaced apart from the ball screw when the crosshead is viewed from a direction parallel to the central axis.

6. The injection molding system of claim 5.

7. a first tie bar and a second tie bar supported by the fixed mounting portion and the base, respectively, in parallel with the central axis and positioned above the ball screw; a third tie bar and a fourth tie bar supported by the fixed mounting portion and the base, respectively, in parallel with the central axis and positioned below the ball screw; The injection molding system of claim 4 , comprising:

8. the platen is supported by four tie bars, i.e., the first tie bar, the second tie bar, the third tie bar, and the fourth tie bar, so as to be slidable parallel to the mold clamping direction, The platen is a first flange that rotatably supports the first connecting rod; a second flange that rotatably supports the second connecting rod; Equipped with the first tie bar overlaps with the second tie bar when the first tie bar and the second tie bar are viewed from a direction parallel to a rotation axis of the first connecting rod at the first flange, the first flange does not overlap with either the first tie bar or the second tie bar when viewed from a direction parallel to a rotation axis of the first connecting rod at the first flange, and is located below the first tie bar and the second tie bar, the third tie bar overlaps with the fourth tie bar when the third tie bar and the fourth tie bar are viewed from a direction parallel to a rotation axis of the second connecting rod at the second flange, When the second flange is viewed from a direction parallel to a rotation axis of the second connecting rod at the second flange, the second flange does not overlap with the third tie bar and the fourth tie bar, and is located above the third tie bar and the fourth tie bar.

8. The injection molding system of claim 7.

9. The diameters of the four tie bars, i.e., the first tie bar, the second tie bar, the third tie bar, and the fourth tie bar, are the same, An end portion of each of the four tie bars in the mold opening direction is provided with a male screw thread having the same diameter as the diameter of each of the four tie bars.

8. The injection molding system of claim 7.

10. a rotation suppression portion that suppresses the crosshead from rotating in response to the rotation of the ball screw; The injection molding system of claim 2 .

11. the rotation suppressing portion has two shaft bodies extending parallel to an axial direction of the ball screw, the two shaft bodies are supported by the base and face each other across the ball screw, The crosshead is supported by the two shaft bodies when viewed from a direction parallel to the central axis, the crosshead penetrating the crosshead.

11. The injection molding system of claim 10.

12. The drive unit overlaps with the toggle mechanism in a direction perpendicular to the central axis. The injection molding system of claim 2 .

13. 1. A method for extruding a molded product from a movable die in an injection molding apparatus that performs injection molding of a molded product using a mold that is composed of a fixed die and a movable die assembled to the fixed die, comprising: The injection molding apparatus a fixed mold mounting portion to which the fixed mold is attached; a platen to which the movable mold is attached so as to face the fixed mold in a predetermined mold clamping direction and which is movable in parallel with the mold clamping direction; a toggle-type mold clamping mechanism that clamps the fixed mold and the movable mold together by moving the platen in the mold clamping direction, and opens the fixed mold and the movable mold together by moving the platen in a mold opening direction opposite to the mold clamping direction; a push-out member provided so that its position relative to the fixed mounting portion does not change; Equipped with the toggle-type mold clamping mechanism moves the platen in the mold opening direction, causing the ejection member to eject the molded product from the movable mold; Molded product extrusion method.

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