Injection molding apparatus and injection unit

Abstract

This invention provides a technology that can suppress the decrease in injection pressure in an injection molding apparatus. [Solution] The injection molding apparatus comprises an injection unit and a mold opening / closing unit. The injection unit comprises a material supply port, a material flow path communicating with the material supply port through which the material flows, an injection control unit having a cylinder and a plunger communicating with the material flow path and controlling the injection of the material, and a nozzle section communicating with the cylinder and injecting the material. The material flow path comprises a first flow path communicating with the cylinder and a second flow path extending in a second direction intersecting the first direction in which the first flow path extends and communicating with the first flow path and the material supply port. The nozzle section comprises a nozzle and a shut-off pin that controls the opening and closing of the nozzle by forward and backward movement. The nozzle section communicates with the cylinder such that a third direction in which the plunger extends and a fourth direction in which the shut-off pin extends intersect, and the cylinder and the nozzle section communicate without the use of other components.

Description

Technical Field

[0001] The present disclosure relates to an injection molding apparatus and an injection unit.

Background Art

[0002] Patent Document 1 discloses an injection device for a resin that is injection-molded at a low viscosity and a low injection pressure, such as a liquid curable resin material typified by a liquid silicone resin. In this injection device, a shut-off pin for opening and closing a nozzle hole is disposed inside a nozzle through which the resin is injected.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Depending on the connection configuration between a nozzle portion having a shut-off pin and a supply path for supplying resin into the nozzle portion, various problems such as a decrease in injection pressure may occur, and there has been room for improvement.

Means for Solving the Problems

[0005] According to a first embodiment of the present disclosure, an injection molding apparatus is provided for performing injection molding of a molded product using a mold. The injection molding apparatus comprises an injection unit for injecting material into the mold, and a mold opening / closing unit to which the mold is attached and for opening and closing the mold, wherein the injection unit has a material supply port into which the material is supplied, a material flow path communicating with the material supply port and through which the material flows, a cylinder communicating with the material flow path, and a plunger that moves forward and backward within the cylinder, and an injection control unit for controlling the injection of the material, and a nozzle unit communicating with the cylinder and for injecting the material, wherein the material flow path is The nozzle portion has a first flow path communicating with the cylinder, and a second flow path extending in a second direction intersecting the first direction in which the first flow path extends, and communicating with the first flow path and the material supply port. The nozzle portion has a nozzle and a shut-off pin that controls the opening and closing of the nozzle by forward and backward movement. The nozzle portion communicates with the cylinder such that the third direction in which the plunger extends and the fourth direction in which the shut-off pin extends intersect, and the cylinder and the nozzle portion communicate without the use of other members.

[0006] According to a second embodiment of the present disclosure, an injection unit is provided. The injection unit comprises an injection control unit for controlling the injection of the material, having a material supply port into which a material is supplied; a material flow path communicating with the material supply port and through which the material flows; a cylinder communicating with the material flow path; a plunger moving forward and backward within the cylinder; and a nozzle unit communicating with the cylinder for injecting the material. The material flow path has a first flow path communicating with the cylinder; and a second flow path extending in a second direction intersecting a first direction in which the first flow path extends, and communicating with the first flow path and the material supply port. The nozzle unit comprises a nozzle and a shut-off pin for controlling the opening and closing of the nozzle by forward and backward movement. The nozzle unit communicates with the cylinder such that a third direction in which the plunger extends intersects with a fourth direction in which the shut-off pin extends, and the cylinder and the nozzle unit communicate without the use of other components. [Brief explanation of the drawing]

[0007] [Figure 1] This is a cross-sectional view showing the schematic configuration of an injection molding apparatus. [Figure 2] This is a cross-sectional view showing the schematic configuration of an injection molding apparatus. [Figure 3] This is a perspective view showing the connection between the moving part and the injection part. [Figure 4] This is a perspective view showing how the injection unit is connected to the moving unit. [Figure 5] This is a view from below showing the injection unit fixed to the moving unit. [Figure 6] This is a cross-sectional view showing how the injection unit is fixed to the moving unit. [Figure 7] This is a diagram showing the detailed configuration of the material flow path. [Figure 8] This diagram shows a magnified view of a portion of the material flow path. [Figure 9] This diagram shows the positional relationship between the plug and the material flow path. [Modes for carrying out the invention]

[0008] A. First Embodiment: Figure 1 is a cross-sectional view showing the schematic configuration of the injection molding apparatus 10. Figure 1 shows arrows representing the mutually orthogonal X, Y, and Z directions. The X and Y directions are parallel to the horizontal plane. The Z direction is parallel to the vertical direction. The X, Y, and Z directions in Figure 1 and the X, Y, and Z directions in other figures point to the same directions. When specifying the direction, the positive direction, which is the direction pointed to by the arrow, is denoted as "+", and the negative direction, which is the direction opposite to the direction pointed to by the arrow, is denoted as "-", and both positive and negative signs are used in the direction notation. The +Z direction is also called upward, and the -Z direction is also called downward.

[0009] The injection molding apparatus 10 forms a molded product by injecting material into a mold 900 mounted on the injection molding apparatus 10. In this embodiment, a liquid material with relatively low viscosity is used as the material for the molded product. In this embodiment, a two-component thermosetting material is used as the liquid material, which consists of a first liquid and a second liquid that are pre-mixed. The first liquid contains the main component of the thermosetting material. For example, a silicone polymer is used as the main component. The second liquid contains a polymerization initiator that starts the polymerization reaction of the two-component thermosetting material.

[0010] The injection molding apparatus 10 comprises a mold opening / closing unit 220, an injection unit 250, and a control unit 500. In this embodiment, the injection unit 250 and the mold opening / closing unit 220 are positioned side by side in the direction of gravity, i.e., in the -Z direction. In other words, the injection molding apparatus 10 in this embodiment is configured as a vertical injection molding apparatus 10.

[0011] The control unit 500 is comprised of a computer comprising one or more processors, memory, and an input / output interface for inputting and outputting signals to and from the outside. The control unit 500 performs various functions, such as executing the process of molding a molded product, by having the processor execute programs and instructions loaded into the main memory. Alternatively, instead of being comprised of a computer, the control unit 500 may be implemented by a configuration combining multiple circuits to realize at least some of each function.

[0012] The mold opening / closing unit 220 includes a fixed section 210. A molding die 900 is attached to the fixed section 210. The fixed section 210 includes a fixed platen 211 and a movable platen 212. The fixed platen 211 and the movable platen 212 are plate-shaped members. The fixed platen 211 is fixed to the upper end of a tie bar 213 that extends vertically, such that its plate surface is parallel to the horizontal direction. The movable platen 212 is positioned below the fixed platen 211 and opposite to the fixed platen 211, such that its plate surface is parallel to the horizontal direction. The fixed mold 901 of the molding die 900 is mounted on the fixed platen 211, and the movable mold 902 of the molding die 900 is mounted on the movable platen 212. The fixed mold 901 and the movable mold 902 are attached to the fixed platen 211 and the movable platen 212, respectively, by bolts or clamping mechanisms.

[0013] The mold opening / closing unit 220 opens and closes the mold 900 mounted on the fixed part 210. The mold opening / closing unit 220 rotates a ball screw 221 by driving a motor (not shown) under the control of the control unit 500, and moves a movable platen 212 coupled to the ball screw 221 along the tie bar 213. As the movable platen 212 moves along the tie bar 213, the mold 900 mounted on the fixed part 210 is opened and closed. When the movable platen 212 moves in the +Z direction, the mold 900 is clamped, and when the movable platen 212 moves in the -Z direction, the mold 900 is opened. When the mold 900 is clamped, the cavity Cv is partitioned by the fixed mold 901 and the movable mold 902. The cavity Cv is a space having a shape corresponding to the shape of the molded product.

[0014] In this embodiment, the mold 900 has a heater 903 for heating the mold 900 to cure the material filled in the cavity Cv. The temperature of the heater 903 is controlled by the control unit 500. The mold 900 may be made of metal, resin, or ceramic. A metal mold 900 is also called a mold.

[0015] The fixed mold 901 has a gate opening 904 which is a hole penetrating the fixed mold 901 in the vertical direction. The material is filled into the cavity Cv through the gate opening 904. The fixed mold 901 is mounted on the fixing part 210 such that the gate opening 904 faces the nozzle opening 321 of the nozzle part 320 in the vertical direction.

[0016] The injection unit 250 has an injection part 230 and a moving part 240.

[0017] The injection part 230 injects the material supplied from an external tank through a pump. The injection part 230 is provided above the fixing part 210 and the mold opening / closing unit 220. The injection part 230 is provided so as to be movable in the vertical direction along a guide member 242 described later. The injection part 230 includes a material supply port 319, a material flow path 310, a nozzle part 320, and an injection control part 330.

[0018] The material is supplied to the material supply port 319 from the outside.

[0019] The material flow path 310 communicates with the material supply port 319. The material flows inside the material flow path 310. A valve part 315 configured as a check valve is arranged in the material flow path 310.

[0020] The injection control part 330 controls the injection of the material under the control of the control part 500. The injection control part 330 has a cylinder 313, a plunger 332, and a plunger drive part 333 including a motor. The cylinder 313 communicates with the material flow path 310. The plunger 332 moves forward and backward along the X direction inside the cylinder 313 when the control part 500 controls the drive of the plunger drive part 333. When the plunger 332 retreats in the direction away from the nozzle part 320 inside the injection cylinder 331, the material is sucked and measured into the injection cylinder 331. When the plunger 332 advances in the direction approaching the nozzle part 320 inside the injection cylinder 331, the sucked material is supplied to the nozzle part 320.

[0021] The nozzle section 320 injects the material supplied by the injection control unit 330. The nozzle section 320 has a nozzle passage 322 and a shut-off pin 334. The nozzle passage 322 communicates with the cylinder 313. A nozzle opening 321 is formed at the tip of the nozzle section 320. The shut-off pin 334 controls the opening and closing of the nozzle opening 321 by moving forward and backward within the nozzle passage 322 along the Z direction.

[0022] The shut-off pin 334 is inserted into the nozzle channel 322 from the end of the nozzle channel 322 opposite to the nozzle opening 321. The shut-off pin 334 is a cylindrical member whose diameter is smaller than the diameter of the nozzle channel 322, and is provided to be movable along the Z direction within the nozzle channel 322. The shut-off pin 334 is driven by the shut-off pin drive unit 338 under the control of the control unit 500. In this embodiment, the shut-off pin drive unit 338 is connected to the nozzle section 320 in the X direction, which intersects the Z direction, the direction in which the nozzle section 320 and the retaining plate 260 (described later) are aligned. More specifically, the shut-off pin drive unit 338 is connected to the nozzle section 320 on the opposite side of the injection control unit 330.

[0023] The shut-off pin drive unit 338, for example, has an air cylinder and uses compressed air to move the shut-off pin 334 within the nozzle passage 322. As the shut-off pin 334 moves in the -Z direction within the nozzle passage 322, the nozzle opening 321 is closed by the end of the shut-off pin 334 on the nozzle opening 321 side, stopping the injection of material from the nozzle opening 321. As the shut-off pin 334 moves in the +Z direction within the nozzle passage 322, the nozzle opening 321 opens, and material can be injected from the nozzle opening 321. The shut-off pin drive unit 338 is not limited to an air cylinder; it may also use a motor or gears to drive the shut-off pin 334.

[0024] The movable part 240 is located above the injection unit 230. The movable part 240 moves the injection unit 250 relative to the mold opening / closing unit 220. The movable part 240 comprises a movable member 241, a guide member 242, a base 243, a screw shaft 244, a ball nut 245, and a movable motor 246. The screw shaft 244 and the ball nut 245 constitute a ball screw.

[0025] The injection unit 230 is fixed to the movable member 241. The movable member 241 is attached to the guide member 242, which is a columnar member extending vertically upward from the top of the fixed part 210, so that it can move along the guide member 242. The base 243 is fixed to the upper end of the guide member 242. The screw shaft 244 is fixed to the base 243 so that it protrudes downward from the base 243. The axis direction of the screw shaft 244 is along the vertical direction. The ball nut 245 is attached to the screw shaft 244 and is fixed to the connecting member 247 which is fixed to the movable member 241. The moving motor 246 is driven under the control of the control unit 500 and rotates the screw shaft 244 around its axis. As the screw shaft 244 rotates, the ball nut 245, the connecting member 247, and the movable member 241 move vertically, and the injection unit 230 moves vertically as a result. As the injection unit 230 moves in the -Z direction, the nozzle unit 320 comes into contact with the fixed mold 901 so that the nozzle opening 321 and the gate opening 904 are in communication. As the injection unit 230 moves in the +Z direction, the nozzle unit 320 moves away from the fixed mold 901. Figure 2 shows the state in which the injection unit 230 has been moved to a position where the nozzle unit 320 and the fixed mold 901 are in contact.

[0026] Figure 3 is a perspective view showing the connection between the movable part 240 and the injection part 230 of the injection unit 250. In Figure 3, the guide member 242 and other components are omitted from the illustration. In this embodiment, the injection unit 250 includes a holding plate 260. The holding plate 260 is connected to the injection part 230 of the injection unit 250 and holds the injection part 230. In this embodiment, the nozzle part 320 of the injection part 230 is connected to the holding plate 260. Specifically, the +Z end of the nozzle part 320 of the injection part 230 is connected to the holding plate 260 by a bolt. The injection control unit 330 of the injection part 230 is connected to the nozzle part 320. In other words, the injection control unit 330 is connected to the holding plate 260 via the nozzle part 320. The holding plate 260 has a substantially rectangular flat plate shape. The longitudinal direction of the holding plate 260 is along the X direction. The retaining plate 260 is positioned below the movable member 241 and parallel to the movable member 241.

[0027] The movable part 240 has a support part 270 that supports the holding plate 260. The support part 270 is fixed to the -Z direction side of the movable member 241 of the movable part 240. In this embodiment, the support part 270 is composed of a plurality of L-shaped fasteners. Specifically, the support part 270 includes a pair of first fasteners 271 and a pair of second fasteners 272. Each fastener of the pair of first fasteners 271 is arranged so that its L-shaped bent tip faces the other along the Y direction. Each fastener of the pair of second fasteners 272 is arranged so that its L-shaped bent tip faces the other along the Y direction. The spacing between each fastener in the pair of first fasteners 271 in the Y direction is equal to the spacing between each fastener in the pair of second fasteners 272 in the Y direction. The pair of first fasteners 271 and the pair of second fasteners 272 are arranged side by side in the X direction.

[0028] Figure 4 is a perspective view showing how the injection unit 230 is connected to the movable unit 240. As described above, the support unit 270 is composed of a pair of first fixing devices 271 and a pair of second fixing devices 272, so that an insertion space IS is formed below the movable member 241 for inserting the retaining plate 260 along the -X direction. When the operator fixes the injection unit 230 to the movable unit 240, the operator inserts the retaining plate 260 to which the injection unit 230 is connected into the insertion space IS from the +X direction to the -X direction. When the operator removes the injection unit 230 from the movable unit 240 for maintenance or cleaning, the operator moves the retaining plate 260 to which the injection unit 230 is connected from the -X direction to the +X direction. Thus, in this embodiment, the retaining plate 260 that holds the injection unit 230 is slidably provided with respect to the support unit 270 of the movable unit 240.

[0029] Figure 5 is a view from below of the injection unit 230 fixed to the movable unit 240. The retaining plate 260 has a first groove 261 and a second groove 262 of different shapes on its end face 269 in the direction of sliding relative to the support unit 270. In this embodiment, when the retaining plate 260 is viewed from below, the first groove 261 has a U-shape, and the second groove 262 has a V-shape.

[0030] The movable part 240 has a first restricting part 281 and a second restricting part 282. In this embodiment, the first restricting part 281 and the second restricting part 282 are provided on the lower surface of the movable member 241. The first restricting part 281 and the second restricting part 282 each have a cylindrical shape with the same diameter. The first restricting part 281 and the second restricting part 282 are spaced apart in the Y direction, but their positions are the same in the X direction.

[0031] The first restricting portion 281 contacts the first groove 261 formed in the retaining plate 260 when the retaining plate 260 is supported by the support portion 270. The second restricting portion 282 contacts the second groove 262 formed in the retaining plate 260 when the retaining plate 260 is supported by the support portion 270. The length of the first groove 261 in the direction along the end face 269 is greater than the diameter of the first restricting portion 281. When the second restricting portion 282 contacts the triangular second groove 262 at two points, the first restricting portion 281 contacts the rectangular first groove 261 at one point. The first restricting portion 281 and the second restricting portion 282 function as restricting the movement of the retaining plate 260 in the -X direction relative to the support portion 270. Furthermore, the first restricting section 281 and the second restricting section 282 function as positioning sections that position the holding plate 260 relative to the support section 270 in the X and Y directions.

[0032] Figure 6 is a cross-sectional view showing how the injection unit 230 is fixed to the movable unit 240. The injection unit 250 has a fixing mechanism 290 that fixes the holding plate 260 to the movable unit 240. In this embodiment, four fixing mechanisms 290 are arranged at positions corresponding to the four corners of the holding plate 260. Each fixing mechanism 290 has a screw 291 and a spring 292 provided around the threads of the screw 291. The spring 292 constantly biases the screw 291 in the opposite direction to the holding plate 260, i.e., in the +Z direction. After the holding plate 260 is supported by the support part 270, the screw 291 is screwed into the screw hole 264 of the holding plate 260 through a through hole 293 provided in the movable member 241, thereby fixing the injection unit 230 held by the holding plate 260 to the movable unit 240. In this embodiment, a retaining member 294 is placed at the opening of the through hole 293 to prevent the screw 291 from coming out of the through hole 293.

[0033] When the retaining plate 260 is moved in the -X direction and supported by the support part 270, the screw 291 is biased in the opposite direction to the retaining plate 260 by the spring 292, so the screw 291 does not come into contact with the retaining plate 260 through the through hole 293. This allows the retaining plate 260 to be easily moved toward the insertion space IS. When removing the injection unit 230 from the moving unit 240, the screw 291 is loosened and released from the screw hole 264. In this state, the retaining plate 260 is supported by the support part 270 without falling in the -Z direction. Even in this state, the screw 291 is biased in the opposite direction to the retaining plate 260 by the spring 292, so the screw 291 does not come into contact with the retaining plate 260 through the through hole 293. Therefore, the operator can easily remove the injection unit 230 from the moving unit 240.

[0034] Figure 7 shows the detailed configuration of the material flow path 310. The material flow path 310 has a first flow path 311 and a second flow path 312. The first flow path 311 communicates with the cylinder 313. The first flow path 311 extends along a first direction D1. In this embodiment, the first direction D1 is the Z direction. At the -Z end of the first flow path 311, the first flow path 311 communicates with the cylinder 313. In this embodiment, the first flow path 311 is connected to the cylinder 313 near the tip of the plunger 332 when the plunger 332 is in its furthest forward position within the cylinder 313. Furthermore, if the distance from the tip of the plunger 332 when the plunger 332 is furthest forward to the tip of the plunger 332 when the plunger 332 is furthest retracted is divided into a front portion FP and a rear portion RP, the first flow path 311 is connected to the cylinder 313 at a position corresponding to the front portion FP.

[0035] In this embodiment, a valve 315 is provided in the first flow path 311. The valve 315 blocks the flow of material through the material flow path 310 for at least a portion of the time during material injection. More specifically, the valve 315 blocks the flow of material through the material flow path 310 for at least a portion of the time during material injection to prevent backflow of material from the cylinder 313 to the material supply port 319. It is not necessary for the valve 315 to block the flow of material through the material flow path 310 for the entire time during material injection. For example, it is permissible for a small amount of material to pass through the valve 315 at the start of the forward movement of the plunger 332 during material injection and at the end of the forward movement.

[0036] The second channel 312 communicates with the first channel 311 and the material supply port 319. The second channel 312 extends in a second direction D2 that intersects with the first direction D1. In this embodiment, the second direction D2 is the X direction. At the -X end of the second channel 312, the second channel 312 communicates with the first channel 311. At the +X end of the second channel 312, the second channel 312 communicates with the material supply port 319. More specifically, at the +X end of the second channel 312, the second channel 312 communicates with the material supply port 319 through a third channel 323 that extends in the first direction D1. The third channel 323 is part of the material channel 310.

[0037] The nozzle portion 320 communicates with the cylinder 313 such that the third direction D3, to which the plunger 332 extends, and the fourth direction D4, to which the shut-off pin 334 extends, intersect. In this embodiment, the third direction D3 is the X direction. In this embodiment, the fourth direction D4 is the Z direction. That is, in this embodiment, both the first direction D1 and the fourth direction D4 are the Z direction, and both the second direction D2 and the third direction D3 are the X direction. The cylinder 313 and the nozzle portion 320 communicate without any other components in between. In other words, the cylinder 313 and the nozzle portion 320 are connected by the shortest possible distance.

[0038] When the movable part 240, including the movable member 241 and tie bar 213, is viewed along the fourth direction D4 to which the shut-off pin 334 extends, the movable part 240 is positioned in conjunction with the nozzle part 320. In other words, in this embodiment, the movable part 240 and the nozzle part 320 are aligned in the direction of gravity.

[0039] Figure 8 is a magnified view of a portion of the material channel 310. The material channel 310 has an opening 340. The opening 340 is provided on at least one wall surface of the material channel forming member 318 that forms the material channel 310, at a position that overlaps with the first channel 311 in a first direction D1, or at a position that overlaps with the second channel 312 in a second direction D2. In this embodiment, the material channel 310 is provided with a first opening 341, a second opening 342, and a third opening 343 as the opening 340. The first opening 341 is provided at a position that overlaps with the first channel 311 in the first direction D1, and the second opening 342 and the third opening 343 are provided at positions that overlap with the second channel 312 in the second direction D2.

[0040] Each opening 340 is provided with a plug 350 that can be attached to or removed from the opening 340. In this embodiment, the plug 350 has a screw-like shape with a head 351 and a male threaded portion 352. The opening 340 has a recess 344 that accommodates the head 351 and a female threaded portion 345 into which the male threaded portion 352 of the plug 350 is screwed. The opening 340 is closed when the male threaded portion 352 of the plug 350 is screwed into the female threaded portion 345 of the opening 340. The operator can clean the inside of the material flow path 310 by removing the injection unit 230 from the moving unit 240 and removing the plug 350 from the opening 340.

[0041] Figure 9 shows the positional relationship between the plug 350 and the material flow path 310. Figure 9 shows the arrangement of the plug 350 when viewed along the extending direction of the second flow path 312. When the plug 350 is installed in the opening 340, the end 353 of the plug 350 on the material flow path 310 side forms a part of the inner wall surface 314 of the material flow path 310. At this time, at least a part of the end 353 of the plug 350 on the material flow path 310 side is located on the same plane as the inner wall surface 314 of the material flow path 310. In this embodiment, the end 353 of the plug 350 has a circular end face, and its center lies on the same cylindrical surface as the inner wall surface 314 of the material flow path 310. Note that the end 353 of the plug 350 is not limited to a flat shape; if the end of the plug 350 is formed at an acute angle or is formed on a curved surface, it may have a point-like shape.

[0042] In the injection molding apparatus 10 of the first embodiment described above, the cylinder 313 provided in the injection control unit 330 and the nozzle unit 320 are directly connected. Therefore, the injection pressure generated by the injection control unit 330 can be efficiently transmitted to the nozzle unit 320. As a result, the decrease in injection pressure is suppressed, and the material can be injected appropriately.

[0043] Furthermore, in this embodiment, the material flow path 310 includes a first flow path 311 along a first direction D1 and a second flow path 312 along a second direction D2 intersecting the first direction D1. The second flow path 312 communicates with the material supply port 319 via a third flow path 323 along the first direction D1. By configuring the material flow path 310 in this bent shape, it becomes possible to arrange the material flow path 310 so as to weave between the moving section 240 and the injection control unit 330. As a result, the moving section 240 and the injection control unit 330 can be suitably arranged in the injection molding apparatus 10. For example, if the material flow path 310 extends in only one direction, it may be necessary to lengthen the injection control unit 330 along the second direction D2 or to offset the nozzle section 320 from the moving section 240, but this is not necessary in this embodiment. As a result, the weight balance of the entire injection molding apparatus 10 is suppressed, and the rigidity and strength of the entire apparatus are suppressed.

[0044] Furthermore, in this embodiment, the first channel 311 of the material channel 310 is connected to the cylinder 313 near the tip of the plunger 332 when the plunger 332 is in its furthest forward position within the cylinder 313. Therefore, the material can be suitably drawn from the material channel 310 and metered by the retraction movement of the plunger 332.

[0045] Furthermore, in this embodiment, the material flow path 310 has a valve 315 that blocks the flow of material through the material flow path 310 for at least a portion of the time during material injection. Therefore, the injection pressure generated by the forward movement of the plunger 332 provided in the injection control unit 330 can be transmitted to the nozzle unit 320 more efficiently.

[0046] Furthermore, in this embodiment, the valve 315 is provided in the first flow path 311 connected to the cylinder 313. As a result, the valve 315 is located closer to the injection control unit 330, which allows the injection pressure generated by the injection control unit 330 to be transmitted to the nozzle 320 more efficiently.

[0047] Furthermore, in this embodiment, the material flow path 310 has an opening 340 at at least one of the following locations: one where it overlaps with the first flow path 311 in the first direction D1, or the other where it overlaps with the second flow path 312 in the second direction D2. The opening 340 is provided with a plug 350 that can be attached to or removed from the opening 340. Therefore, by removing the plug 350 provided in the material flow path 310, the inside of the material flow path 310 can be easily cleaned through the opening 340.

[0048] Furthermore, in this embodiment, at least a portion of the end 353 of the plug 350 on the material flow path 310 side and the inner wall surface 314 of the material flow path 310 are located on the same plane. Therefore, the presence of the plug 350 suppresses material retention in the material flow path 310, thereby suppressing a decrease in injection efficiency. In addition, because material retention is suppressed, the cleaning process when cleaning the material flow path 310 can be kept from becoming prolonged.

[0049] Furthermore, in this embodiment, the moving part 240 that moves the injection unit 250 relative to the mold opening / closing unit 220 is positioned overlapping with the nozzle part 320 when viewed along the direction in which the shut-off pin 334 extends. Therefore, the injection control unit 330 can be positioned close to the nozzle part 320. As a result, when the injection unit 250 moves relative to the mold opening / closing unit 220, the load on the moving part 240, such as the tie bar 213, can be reduced compared to when the injection control unit 330 is positioned close to the moving part 240. Consequently, the lifespan of the moving part 240 can be extended.

[0050] Furthermore, in this embodiment, the movable part 240 has a support part 270 for supporting the retaining plate 260 that holds the injection part 230, and the retaining plate 260 is slidably mounted relative to the support part 270. Therefore, when removing the injection part 230 held by the retaining plate 260 from the movable part 240, the retaining plate 260 is supported by the support part 270, and in that state, the retaining plate 260 can be slid away from the support part 270 and moved. Consequently, when cleaning or maintaining the injection part 230, the injection part 230 can be easily removed from the movable part 240.

[0051] Furthermore, in this embodiment, the injection unit 250 and the mold opening / closing unit 220 are positioned side by side in the direction of gravity. In other words, the injection molding apparatus 10 of this embodiment is configured as a vertical injection molding apparatus 10. According to this embodiment, in such a vertical injection molding apparatus 10, the injection unit 230 can be easily removed from the moving unit. In particular, in this embodiment, the support unit 270 supports the holding plate 260 from vertically below. Therefore, when removing the injection unit 230 from the moving unit 240, it can be easily removed without dropping the injection unit 230. As a result, there is no need to increase the number of personnel to support the injection unit 230 when removing it. Accordingly, the injection unit 230 can be easily removed without increasing the number of workers or other man-hours. In addition, according to this embodiment, the injection unit 230 can be easily removed and easily installed at the same time. Therefore, it becomes easy to attach another injection unit 230 to the injection molding apparatus 10 while the injection unit 230 is being cleaned, thereby minimizing the downtime of the apparatus and improving the manufacturing efficiency of molded products.

[0052] Furthermore, in this embodiment, the nozzle section 320 is equipped with a shut-off pin 334 that moves forward and backward within the nozzle flow path 322. Therefore, the injection molding apparatus 10 can inject materials with relatively low viscosity. As a result, the injection section 230 can be easily removed from the injection molding apparatus 10 that injects materials with low viscosity.

[0053] Furthermore, in this embodiment, the nozzle section 320 is connected to the retaining plate 260, and the injection control unit 330 is connected to the nozzle section 320. With this configuration, there is no need to connect the injection control unit 330 to the retaining plate 260, so the size of the retaining plate 260 can be reduced. As a result, the injection molding apparatus 10 can be made more compact.

[0054] Furthermore, in this embodiment, the shut-off pin drive unit 338, which drives the shut-off pin 334, is connected to the nozzle unit 320 in a direction intersecting the direction in which the nozzle unit 320 and the retaining plate 260 are aligned. Therefore, the possibility of the shut-off pin drive unit 338 interfering with other parts when the retaining plate 260 is slid and moved is reduced. As a result, the injection unit 230 can be easily removed.

[0055] Furthermore, in this embodiment, the injection unit 250 has a fixing mechanism 290 that fixes the retaining plate 260 to the movable part 240. The fixing mechanism 290 includes a screw 291 and a spring 292 provided around the threads of the screw 291. The screw 291 is screwed into a screw hole 264 formed in the retaining plate 260 through a through hole 293 provided in the movable part 240. With this configuration, when removing the screw 291 from the screw hole 264, the spring 292 can reliably separate the screw 291 from the retaining plate 260. Therefore, the injection unit 230 can be easily removed. In addition, in this embodiment, a retaining member 294 is placed at the opening of the through hole 293 into which the screw 291 is inserted. Therefore, the risk of the screw 291 falling or being lost can be suppressed, and the number of steps required to insert the screw 291 into the through hole 293 can be reduced.

[0056] Furthermore, in this embodiment, the retaining plate 260 has a first groove 261 and a second groove 262 of different shapes on its end face 269 in the direction of sliding relative to the support portion 270, and the moving portion 240 has a first restricting portion 281 that contacts the first groove 261 and a second restricting portion 282 that contacts the second groove 262 when the retaining plate 260 is supported by the support portion 270.Therefore, the retaining plate 260 can be accurately positioned relative to the moving portion 240.In particular, in this embodiment, since the first groove 261 is U-shaped and the second groove 262 is V-shaped, even if there are individual errors in the distance between the first restricting portion 281 and the second restricting portion 282, the retaining plate 260 can be accurately positioned on the moving portion 240.

[0057] B. Other embodiments: (B1) In the above embodiment, the first flow path 311 of the material flow path 310 is connected to the cylinder 313 near the tip of the plunger 332 when the plunger 332 is in its furthest forward position within the cylinder 313. In contrast, the first flow path 311 may be connected to the cylinder 313 behind the tip of the plunger 332 when the plunger 332 is in its furthest forward position within the cylinder 313.

[0058] (B2) In the above embodiment, the material flow path 310 is provided with a valve 315 that blocks the flow of material in the material flow path 310 for at least a portion of the time during material injection. In contrast, the material flow path 310 does not have to be provided with a valve 315. For example, the valve 315 can be provided outside the injection molding apparatus 10. Also, in the above embodiment, the valve 315 is provided in the first flow path 311, but it may also be provided in the second flow path 312.

[0059] (B3) In the above embodiment, an opening 340 is provided in the material flow path 310, and a plug 350 is provided in the opening 340. In contrast, the material flow path 310 does not have to have an opening 340.

[0060] (B4) In the above embodiment, at least a portion of the end 353 of the plug 350 provided in the opening 340 of the material flow path 310 that is on the material flow path 310 side is on the same plane as the inner wall surface 314 of the material flow path 310. In contrast, at least a portion of the end 353 of the plug 350 that is on the material flow path 310 side may be set back from or protrude from the inner wall surface 314 of the material flow path 310.

[0061] (B5) In the above embodiment, when the movable part 240, including the movable member 241 and tie bar 213, is viewed along the fourth direction D4 to which the shut-off pin 334 extends, the movable part 240 is positioned in overlap with the nozzle part 320. In contrast, a configuration is also possible in which the movable part 240 and the nozzle part 320 do not overlap when viewed along the fourth direction.

[0062] (B6) In the above embodiment, the injection unit 250 and the mold opening / closing unit 220 are positioned side by side in the direction of gravity. In contrast, the injection unit 250 and the mold opening / closing unit 220 may be positioned side by side in the horizontal direction. In other words, the injection molding apparatus 10 may be configured as a horizontal injection molding apparatus 10.

[0063] (B7) In the above embodiment, the injection molding apparatus 10 is equipped with a shut-off pin 334 and a shut-off pin drive unit 338. However, the injection molding apparatus 10 does not necessarily have to be equipped with a shut-off pin 334 and a shut-off pin drive unit 338. In other words, the injection molding apparatus 10 may be a molding machine that injects a material with relatively high viscosity.

[0064] (B8) In the above embodiment, the nozzle unit 320 is connected to the holding plate 260, and the injection control unit 330 is connected to the nozzle unit 320. Alternatively, both the nozzle unit 320 and the injection control unit 330 may be connected to the holding plate 260.

[0065] (B9) In the above embodiment, the shut-off pin drive unit 338 is connected to the nozzle portion 320 in a direction intersecting the direction in which the nozzle portion 320 and the retaining plate 260 are aligned. Alternatively, the shut-off pin drive unit 338 may be connected to the nozzle portion 320 along the direction in which the nozzle portion 320 and the retaining plate 260 are aligned.

[0066] (B10) In the above embodiment, the injection molding apparatus 10 is provided with a fixing mechanism 290 for fixing the retaining plate 260 to the movable part 240. This fixing mechanism 290 is not limited to a configuration including a screw 291 and a spring 292, but may also be configured without the spring 292. Furthermore, the fixing mechanism 290 may be provided on a support part 270 provided on the movable part 240, rather than on a movable member 241 provided on the movable part 240.

[0067] (B11) In the above embodiment, the retaining plate 260 has a first groove 261 and a second groove 262, and the moving part 240 has a first restricting part 281 and a second restricting part 282. In contrast, the retaining plate 260 does not have to have a first groove 261 and a second groove 262, and the moving part 240 does not have to have a first restricting part 281 and a second restricting part 282.

[0068] (B12) In the above embodiment, the support portion 270 includes a pair of first fasteners 271 and a pair of second fasteners 272. However, the support portion 270 may include only the pair of first fasteners 271, and each fastener included in the pair of first fasteners 271 may have an elongated shape along the X direction. Furthermore, the shape of the first fasteners 271 and the second fasteners 272 is not limited to L-shapes; for example, they may have a configuration in which a slit into which the side end of the retaining plate 260 is inserted is provided on the inner surface.

[0069] C. Other forms: This disclosure is not limited to the embodiments described above, and can be implemented in various configurations without departing from its spirit. For example, the technical features of the embodiments corresponding to the technical features in each of the embodiments described below can be replaced or combined as appropriate in order to solve some or all of the above-described problems, or to achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.

[0070] (1) According to a first embodiment of the present disclosure, an injection molding apparatus is provided for performing injection molding of a molded product using a mold. The injection molding apparatus comprises an injection unit for injecting material into the mold, and a mold opening / closing unit to which the mold is attached and for opening and closing the mold, wherein the injection unit has a material supply port into which the material is supplied, a material flow path communicating with the material supply port and through which the material flows, a cylinder communicating with the material flow path, and a plunger that moves forward and backward within the cylinder, and an injection control unit for controlling the injection of the material, and a nozzle unit communicating with the cylinder and for injecting the material, wherein the material flow path is The nozzle portion has a first flow path communicating with the cylinder, and a second flow path extending in a second direction intersecting the first direction in which the first flow path extends, and communicating with the first flow path and the material supply port. The nozzle portion has a nozzle and a shut-off pin that controls the opening and closing of the nozzle by forward and backward movement. The nozzle portion communicates with the cylinder such that the third direction in which the plunger extends and the fourth direction in which the shut-off pin extends intersect, and the cylinder and the nozzle portion communicate without the use of other members. In this configuration, the cylinder and nozzle section provided in the injection control unit are directly connected, allowing the injection pressure generated in the injection control unit to be efficiently transmitted to the nozzle section. As a result, the decrease in injection pressure is suppressed, and the material can be injected effectively.

[0071] (2) In the above configuration, the first flow path may be connected to the cylinder near the tip of the plunger when the plunger is in its furthest forward position within the cylinder. In this configuration, the material can be suitably drawn from the material flow path and metered by the retraction of the plunger.

[0072] (3) In the above configuration, the material flow path may have a valve that blocks the flow of the material for at least a portion of the time during the injection of the material. With such a configuration, the injection pressure generated by the injection control unit can be transmitted to the nozzle unit more efficiently.

[0073] (4) In the above configuration, the valve portion may be provided in the first flow path. With this configuration, since the valve portion is provided in a position close to the injection control unit, the injection pressure generated by the injection control unit can be transmitted to the nozzle portion more efficiently.

[0074] (5) In the above embodiment, the material flow path has an opening, the opening is provided at least one of the following positions: one in which it overlaps with the first flow path in the first direction, or one in which it overlaps with the second flow path in the second direction, and the opening may be provided with a plug that can be attached to or removed from the opening. With this embodiment, the inside of the material flow path can be easily cleaned from the opening by removing the plug.

[0075] (6) In the above configuration, at least a portion of the end of the plug on the material flow path side may be on the same plane as the inner wall surface of the material flow path. With this configuration, material stagnation in the material flow path is suppressed, and a decrease in injection efficiency can be suppressed. In addition, since material stagnation is suppressed, the cleaning process can be kept from taking a long time.

[0076] (7) In the above embodiment, the injection unit has a moving part that moves the injection unit relative to the mold opening / closing unit, and when the moving part is viewed along the fourth direction, the moving part may be positioned to overlap with the nozzle part. With this embodiment, the injection control unit can be positioned close to the nozzle part, so when the injection unit moves relative to the mold opening / closing unit, the load on the moving part can be reduced compared to when the injection control unit is positioned close to the moving part.

[0077] (8) According to a second embodiment of the present disclosure, an injection unit is provided. The injection unit comprises an injection control unit for controlling the injection of the material, having a material supply port for which material is supplied, a material flow path communicating with the material supply port and through which the material flows, a cylinder communicating with the material flow path, and a plunger moving forward and backward within the cylinder, and a nozzle unit communicating with the cylinder for injecting the material, wherein the material flow path has a first flow path communicating with the cylinder and a second flow path extending in a second direction intersecting a first direction in which the first flow path extends and communicating with the first flow path and the material supply port, the nozzle unit having a nozzle and a shut-off pin for controlling the opening and closing of the nozzle by forward and backward movement, the nozzle unit communicating with the cylinder such that a third direction in which the plunger extends and a fourth direction in which the shut-off pin extends intersect, and the cylinder and the nozzle unit are in communication without the use of other members. [Explanation of Symbols]

[0078] 10...Injection molding apparatus, 210...Fixed part, 211...Fixed platen, 212...Movable platen, 213...Tie bar, 220...Mold opening / closing unit, 221...Ball screw, 230...Injection part, 240...Moving part, 241...Movable member, 242...Guide member, 243...Base, 244...Screw shaft, 245...Ball nut, 246...Moving motor, 247...Connecting member, 250...Injection unit, 260...Holding plate, 26 1...First groove, 262...Second groove, 264...Screw hole, 269...End face, 270...Support part, 271...First fastener, 272...Second fastener, 281...First restricting part, 282...Second restricting part, 290...Fixing mechanism, 291...Screw, 292...Spring, 293...Through hole, 294...Retaining member, 310...Material flow path, 311...First flow path, 312...Second flow path, 313...Cylinder, 314...Inner wall surface, 31 5... Valve section, 318... Material flow path forming member, 319... Material supply port, 320... Nozzle section, 321... Nozzle opening, 322... Nozzle flow path, 323... Third flow path, 330... Injection control section, 331... Injection cylinder, 332... Plunger, 333... Plunger drive section, 334... Shut-off pin, 338... Shut-off pin drive section, 340... Opening, 341... First opening, 342... Second opening, 3 43...Third opening, 344...Recess, 345...Female threaded section, 350...Plug, 351...Head, 352...Male threaded section, 353...End, 500...Control unit, 900...Molding mold, 901...Fixed mold, 902...Movable mold, 903...Heater, 904...Gate opening, Cv...Cavity, D1...First direction, D2...Second direction, D3...Third direction, D4...Fourth direction, FP...Front section, IS...Insertion space, RP...Rear section

Claims

1. An injection molding apparatus that performs injection molding of molded products using a mold, An injection unit for injecting material into the mold, The mold to which the mold is attached, and a mold opening / closing unit for opening and closing the mold, Equipped with, The injection unit is, A material supply port into which the aforementioned material is supplied, A material flow path is connected to the material supply port and through which the material flows, An injection control unit having a cylinder communicating with the material flow path and a plunger that moves forward and backward within the cylinder, which controls the injection of the material, A nozzle section that communicates with the cylinder and injects the material, It has, The material flow channel is A first flow path communicating with the cylinder, A second flow channel extends in a second direction intersecting the first direction in which the first flow channel extends, and communicates with the first flow channel and the material supply port, It has, The nozzle portion is Nozzle and A shut-off pin that controls the opening and closing of the nozzle by forward and backward movement, It has, The nozzle portion communicates with the cylinder such that the third direction in which the plunger extends and the fourth direction in which the shut-off pin extends intersect. The cylinder and the nozzle portion are in communication without the need for any other components. Injection molding equipment.

2. An injection molding apparatus according to claim 1, The first flow path is connected to the cylinder near the tip of the plunger when the plunger is in its most advanced position within the cylinder. Injection molding equipment.

3. An injection molding apparatus according to claim 1, The material flow path has a valve that blocks the flow of the material for at least a portion of the time during injection of the material. Injection molding equipment.

4. An injection molding apparatus according to claim 3, The valve portion is provided in the first flow path, Injection molding equipment.

5. An injection molding apparatus according to claim 1, The material flow path has an opening, The opening is provided at least one of the following positions: one that overlaps with the first flow path in the first direction, or one that overlaps with the second flow path in the second direction. The opening is provided with a plug that can be attached to or removed from the opening. Injection molding equipment.

6. An injection molding apparatus according to claim 5, At least a portion of the end of the plug on the material flow path side is located on the same plane as the inner wall surface of the material flow path. Injection molding equipment.

7. An injection molding apparatus according to claim 1, The injection unit has a moving part that moves the injection unit relative to the mold opening / closing unit, When the moving part is viewed along the fourth direction, the moving part is positioned to overlap with the nozzle part. Injection molding equipment.

8. A material supply port from which materials are supplied, A material flow path is connected to the material supply port and through which the material flows, An injection control unit having a cylinder communicating with the material flow path and a plunger that moves forward and backward within the cylinder, which controls the injection of the material, A nozzle section that communicates with the cylinder and injects the material, Equipped with, The material flow channel is A first flow path communicating with the cylinder, A second flow channel extends in a second direction intersecting the first direction in which the first flow channel extends, and communicates with the first flow channel and the material supply port, It has, The nozzle portion is Nozzle and A shut-off pin that controls the opening and closing of the nozzle by forward and backward movement, It has, The nozzle portion communicates with the cylinder such that the third direction in which the plunger extends and the fourth direction in which the shut-off pin extends intersect. The cylinder and the nozzle portion are in communication without the need for any other components. Injection unit.

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