Injection molding apparatus and mold

Abstract

To appropriately cool a region of a molding die where hot runners are close to each other.SOLUTION: An injection molding device includes: a stationary die with a first gate opening and a second gate opening different from the first gate opening; a movable die configured to be clamped to the stationary die; a first hot runner that injects a first molding material into a cavity defined by the stationary die and the movable die through the first gate opening; a second hot runner that injects a second molding material into the cavity through the second gate opening; and a cooling part that cools the stationary die. An end face of the stationary die facing the movable die has a first region with a face between the first gate opening and the second gate opening, and a second region different from the first region when viewed along a mold clamping direction. The cooling part is configured such that a cooling capacity for the first region is higher than the cooling capacity for the second region.SELECTED DRAWING: Figure 11

Description

Technical Field

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

Background Art

[0002] Regarding an injection molding apparatus, Patent Document 1 discloses a hot runner mold for injection molding in which a cooling circuit for passing a cooling medium is provided on the outer periphery of a gate bushing having a gate serving as an inlet to a cavity.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above document, the configuration of the cooling circuit when a plurality of hot runners are arranged has not been specifically studied. The inventors of the present application have found that when a plurality of hot runners are arranged in this way, the region where the hot runners are close to each other in the mold tends to become high temperature, which may affect the quality of the molded product. Therefore, a technique capable of appropriately cooling the region where the hot runners are close to each other has been desired.

Means for Solving the Problems

[0005] According to a first embodiment of the present disclosure, an injection molding apparatus is provided. This injection molding apparatus comprises a fixed mold having a first gate opening and a second gate opening different from the first gate opening; a movable mold configured to be clamped to the fixed mold; a first hot runner for injecting a first molding material through the first gate opening into a cavity partitioned by the fixed mold and the movable mold; a second hot runner for injecting a second molding material through the second gate opening into the cavity; and a cooling unit for cooling the fixed mold. The end face of the fixed mold facing the movable mold has, when viewed along the clamping direction, a first region having a surface located between the first gate opening and the second gate opening, and a second region different from the first region. The cooling unit is configured such that the cooling capacity for the first region is higher than the cooling capacity for the second region.

[0006] A second embodiment of the present disclosure provides a mold. The mold includes a fixed mold having a first gate opening and a second gate opening different from the first gate opening; a movable mold; a first opening configured to allow insertion of a first hot runner for injecting a first molding material through the first gate opening into a cavity partitioned by the fixed mold and the movable mold; a second opening configured to allow insertion of a second hot runner for injecting a second molding material through the second gate opening into the cavity; and a cooling section for cooling the fixed mold. The end face of the fixed mold closest to the movable mold has, when viewed along the mold clamping direction, a first region having a surface located between the first gate opening and the second gate opening on the end face, and a second region different from the first region. The cooling section is configured such that the cooling capacity for the first region is higher than the cooling capacity for the second region. [Brief explanation of the drawing]

[0007] [Figure 1] This is a front view showing the schematic configuration of the injection molding apparatus in the first embodiment. [Figure 2] This is a cross-sectional view showing the schematic configuration of the injection unit. [Figure 3] This is a perspective view showing the schematic configuration of a flat screw. [Figure 4] This is a schematic plan view of the barrel. [Figure 5] This is a cross-sectional view showing the schematic configuration of the molding die. [Figure 6] This is a schematic diagram showing the flow path within the mold. [Figure 7] This figure shows a cross-section of the nozzle tip and cooling plate. [Figure 8] This is a perspective view showing the cooling plate. [Figure 9] This is a plan view showing the cavity area screen. [Figure 10] This figure shows a cross-section of XX, as shown in Figure 8. [Figure 11] This diagram illustrates the arrangement of the cooling channels in the first embodiment. [Figure 12] This is an explanatory diagram showing the manufacturing process of a cooling plate. [Figure 13] This diagram illustrates the relationship between the shape of the molded product and the arrangement of the cooling channels. [Figure 14] This diagram illustrates the arrangement of the cooling channels in the second embodiment. [Modes for carrying out the invention]

[0008] A. First Embodiment: Figure 1 is a front view showing the schematic configuration of the injection molding apparatus 100 in the first embodiment. Figure 1 shows arrows indicating the mutually orthogonal X, Y, and Z directions. The X and Y directions are parallel to the horizontal plane, and the Z direction is opposite to the direction of gravity. The X, Y, and Z directions shown in Figure 2 and subsequent figures correspond to the X, Y, and Z directions shown in Figure 1. In the following description, when specifying directions, the positive direction indicated by the arrow will be denoted as "+" and the negative direction opposite to the direction indicated by the arrow will be denoted as "-", and positive and negative signs will be used in conjunction with the direction notation.

[0009] As shown in Figure 1, the injection molding apparatus 100 comprises an injection unit 140 and a clamping device 130. The injection molding apparatus 100 is a horizontal injection molding apparatus, and the injection unit 140 and the clamping device 130 are arranged horizontally. The injection unit 140 and the clamping device 130 are each fixed to a base 20. The base 20 is equipped with a control unit 500. The injection molding apparatus 100 forms a molded product by injecting molding material from the injection unit 140 into a mold 220 mounted on the clamping device 130.

[0010] In this embodiment, a metal mold 220 is mounted on the clamping device 130. The mold 220 mounted on the clamping device 130 is not limited to metal, but may be made of resin or ceramic. A metal mold 220 is referred to as a mold. The mold 220 includes a fixed mold 230 and a movable mold 255. The fixed mold 230 is a mold used in a fixed position on the injection unit 140, and the movable mold 255 is a mold that moves relative to the fixed mold 230 and is configured to be clamped onto the fixed mold 230. The fixed mold 230 is also called the first mold or female mold, and the movable mold 255 is also called the second mold or male mold.

[0011] The clamping device 130 has the function of opening and closing the fixed mold 230 and the movable mold 255. Under the control of the control unit 500, the clamping device 130 rotates a ball screw 132 by driving a mold drive unit 131, which is composed of a motor, and moves the movable mold 255, which is coupled to the ball screw 132, relative to the fixed mold 230 to open and close the molding mold 220. In other words, the fixed mold 230 is stationary in the injection molding apparatus 100, and the molding mold 220 is opened and closed by the relative movement of the movable mold 255 relative to the stationary fixed mold 230. In this embodiment, the movable mold 255 moves in the -Y direction, which is the direction intersecting the vertical direction, to perform clamping. The direction of clamping, that is, the direction in which the movable mold 255 moves relative to the fixed mold 230, is also called the clamping direction. The clamping direction includes both one direction along the same axis and the opposite direction.

[0012] One or more ejector pins 166 are embedded in the movable mold 255. The ejector pin 166 is a rod-shaped member for ejecting the molded product formed in the cavity 221 from the movable mold 255 when moving the movable mold 255. The ejector pin 166 is provided so as to penetrate the movable mold 255 and reach the cavity 221. The rear end of the ejector pin 166 is supported by a support plate 167. A support rod 168 is fixed to the support plate 167, and the support rod 168 is inserted into a through hole formed in the movable mold 255. A spring 169 is inserted into the support rod 168 and is disposed in the space between the movable mold 255 and the support plate 167. The spring 169 biases the support plate 167 so that the head of the ejector pin 166 forms a part of the wall surface of the cavity 221 during molding. An extrusion plate 164 is fixed to the surface of the support plate 167 on the side of the ball screw 132. A thrust bearing 163 is attached to the surface of the extrusion plate 164 on the side of the ball screw 132. The head of the ball screw 132 can contact the thrust bearing 163. Note that, instead of the thrust bearing 163, a thrust sliding bearing or the like may be used.

[0013] A hopper 30 into which the material for the molded product is charged is connected to the injection unit 140. As the material for the molded product, for example, a thermoplastic resin formed in pellet form is used. As the thermoplastic resin, for example, ABS (acrylonitrile butadiene styrene), PC (polycarbonate), POM (polyacetal), PP (polypropylene), PBT (polybutylene terephthalate), etc. are used. The supply of the material to the injection unit 140 is not limited to the hopper 30, and may be performed, for example, through a tube through which the material is pressure-fed.

[0014] The injection unit 140 plasticizes at least a part of the material supplied from the hopper 30 to generate a molding material, and injects the molding material into the cavity 221 partitioned between the fixed mold 230 and the movable mold 255. "Plasticization" is a concept that includes melting, and it is to change from a solid state to a state with fluidity. Specifically, in the case of a material in which glass transition occurs, plasticization means raising the temperature of the material above the glass transition point. In the case of a material in which glass transition does not occur, plasticization means raising the temperature of the material above the melting point.

[0015] FIG. 2 is a cross-sectional view showing a schematic configuration of the injection unit 140. In FIG. 2, for the sake of illustration, each part is shown such that the +Y direction facing right in FIG. 1 faces downward. The injection unit 140 includes a plasticizing unit 110, an injection control mechanism 120, and a nozzle 114.

[0016] The plasticizing unit 110 has a flat screw 111, a barrel 112, and a heater 113. The flat screw 111 is accommodated in the accommodating portion 101. The flat screw 111 is a rotor or simply called a screw. The flat screw 111 is rotationally driven within the accommodating portion 101 about the rotation axis RX by a drive motor 118. In the present embodiment, the direction of the rotation axis RX is along the Y direction. A communication hole 116 is formed at the center of the barrel 112. An injection cylinder 121 described later is connected to the communication hole 116. A check valve 124 is provided in the communication hole 116 upstream of the injection cylinder 121. The rotation of the flat screw 111 by the drive motor 118 and the heating by the heater 113 are controlled by the control unit 500.

[0017] Figure 3 is a perspective view showing the schematic configuration of the flat screw 111. The flat screw 111 has a substantially cylindrical shape in which the height in the direction along its central axis is smaller than its diameter. On the groove-forming surface 201 of the flat screw 111 facing the barrel 112, a spiral groove 202 is formed, centered on the central part 205. The groove 202 communicates with a material inlet 203 formed on the side of the flat screw 111. The material supplied from the hopper 30 is supplied to the groove 202 through the material inlet 203. The groove 202 is formed by being separated by a protruding ridge 204. Figure 3 shows an example in which three grooves 202 are formed, but the number of grooves 202 may be one or two or more. Note that the groove 202 is not limited to a spiral shape, but may also be helical or involute curved, or may extend in an arc from the central part toward the outer circumference.

[0018] Figure 4 is a schematic plan view of the barrel 112. The barrel 112 has an opposing surface 212 that faces the groove-forming surface 201 of the flat screw 111. A communication hole 116 is formed in the center of the opposing surface 212. Multiple guide grooves 211 are formed on the opposing surface 212, connected to the communication hole 116 and extending in a spiral shape from the communication hole 116 toward the outer circumference. The material supplied to the groove 202 of the flat screw 111 is plasticized between the flat screw 111 and the barrel 112 by the rotation of the flat screw 111 and the heating of the heater 113, and flows along the groove 202 and guide grooves 211 as the flat screw 111 rotates, and is guided to the central part 205 of the flat screw 111. The material that has flowed into the central part 205 flows out to the injection control mechanism 120 from the communication hole 116 provided in the center of the barrel 112. Note that the barrel 112 does not necessarily have to be provided with guide grooves 211. Furthermore, the guide groove 211 does not necessarily have to be connected to the communication hole 116.

[0019] As shown in Figure 2, the injection control mechanism 120 includes an injection cylinder 121, a plunger 122, and a plunger drive unit 123. The injection control mechanism 120 has the function of injecting the molding material in the injection cylinder 121 into the cavity 221. Under the control of the control unit 500, the injection control mechanism 120 controls the amount of molding material injected from the nozzle 114, the injection speed, and the injection pressure. The injection cylinder 121 is a substantially cylindrical member connected to the communication hole 116 of the barrel 112 and has a plunger 122 inside. The plunger 122 slides inside the injection cylinder 121 and pressurizes the molding material in the injection cylinder 121 to the nozzle 114 provided in the injection unit 140. As a result, the molding material is injected from the nozzle 114 to the mold 220. The plunger 122 is driven by a plunger drive unit 123 which is composed of a motor.

[0020] As shown in Figure 1, the fixed type 230 has gate openings 170 formed therein. More specifically, the fixed type 230 in this embodiment has a total of six gate openings, including a first gate opening 171 and a second gate opening 172, as described later. In Figure 1, only the first gate opening 171 and the second gate opening 172 of the six gate openings 170 are schematically shown. Details of the gate openings 170 will be described later.

[0021] The control unit 500 is comprised of a computer that includes one or more processors, main memory, and an input / output interface for inputting and outputting signals to and from the outside. The processor loads a program into the main memory and executes it, thereby controlling the injection unit 140 and the clamping device 130 to manufacture molded products.

[0022] Figure 5 is a cross-sectional view showing the schematic configuration of the mold 220. Figure 6 is a schematic diagram showing the in-mold flow path 161 within the mold 220. The in-mold flow path 161 refers to the flow path of the molding material provided within the fixed mold 230. The material injected into the mold 220 from the nozzle 114 of the injection unit 140 reaches the cavity 221 via this in-mold flow path 161. In this embodiment, the in-mold flow path 161 is formed by spaces such as holes and grooves formed in the components constituting the fixed mold 230. Figure 6 corresponds to a schematic diagram showing such an in-mold flow path 161 extracted from the fixed mold 230.

[0023] The mold 220 is configured as a hot runner type mold. Therefore, the molding material in the internal flow channel 161 is heated by a heater provided in the fixed mold 230 and kept in a fluid state. The internal flow channel 161 is also called the "hot runner." The "hot runner type" is also called the "runnerless type."

[0024] The fixed type 230 in this embodiment includes a sprue bush 235, a manifold section 240, six nozzle tips 245, and a cavity plate 254.

[0025] A sprue 236 extending along the Y direction is formed within the sprue bush 235. The sprue 236 forms the inlet end of the mold channel 161. The -Y direction end of the sprue 236 corresponds to the starting end of the mold channel 161. The +Y direction end of the sprue 236 is connected to the manifold channel 241 in the manifold section 240, which will be described later. The tip of the nozzle 114 of the injection unit 140 contacts the -Y direction end of the sprue 236. A locating ring 237 for positioning the injection unit 140 relative to the fixed mold 230 is fixed to the -Y direction side of the sprue bush 235.

[0026] The manifold section 240 is positioned in the +Y direction of the sprue bush 235 and is fixed to the sprue bush 235. A manifold channel 241 is formed within the manifold section 240. The starting end of the manifold channel 241 is connected to the sprue 236, as described above. The manifold channel 241 forms part of the in-mold channel 161 and functions as a channel that distributes the molding material flowing from the nozzle 114 into the mold 220 to each nozzle tip 245. More specifically, the manifold channel 241 extends from the end on the sprue 236 side to the first branching point 242, at which point it branches into three channels extending in different directions. Furthermore, each of the branched channels extends to the second branching point 243, at which point it branches into two channels extending in different directions. A total of six such branched channels are each connected to the tip channel 246 in each nozzle tip 245. The molding material in the manifold passage 241 is heated by a cartridge heater 244 inserted into the manifold section 240.

[0027] Figure 7 shows a cross-section of the nozzle tip 245 and the cooling plate 250. The cross-section shown in Figure 7 is in a different direction from the cross-section shown in Figure 5. As shown in Figures 5 and 7, each nozzle tip 245 is positioned on the +Y direction side of the manifold section 240 and fixed to the manifold section 240. In this embodiment, each nozzle tip 245 is configured as a valve-gate type hot runner nozzle, and the tip flow path 246 within each nozzle tip 245 is opened and closed by the operation of the valve pin 248 shown in Figure 5. The valve pin 248 is operated by the drive of a pin drive unit 249 under the control of the control unit 500. The pin drive unit 249 is configured, for example, by an air-operated, hydraulic, or electric cylinder. In other embodiments, the nozzle tip 245 may be configured, for example, as an open-gate type hot runner nozzle.

[0028] The chip channel 246 forms the end of the in-mold channel 161. Hereinafter, the chip channels 246 formed within each nozzle tip 245 will also be referred to as the first chip channel 246A, the second chip channel 246B, the third chip channel 246C, the fourth chip channel 246D, the fifth chip channel 246E, and the sixth chip channel 246F, respectively.

[0029] As shown in Figures 5 and 7, the cavity plate 254 is positioned in the +Y direction of the manifold section 240. Each nozzle tip 245 is connected to and fixed to the cavity plate 254. The cavity plate 254 forms an end portion of the fixed mold 230, including an end face 233 close to the movable mold 255. The end face 233 includes a cavity section screen 227. The cavity section screen 227 is the portion of the end face 233 that defines the cavity 221, that is, the surface of the end face 233 that defines the cavity 221.

[0030] In this embodiment, the cavity plate 254 has a cooling plate 250. As shown in Figures 5 and 7, the cooling plate 250 is positioned on the +Y side of the nozzle tip 245. In this embodiment, the plate end face 251, which is the -Y side end face of the cooling plate 250, forms the portion of the end face 233 of the fixed mold 230 described above that includes the cavity area screen 227.

[0031] Figure 8 is a perspective view showing the cooling plate 250 in this embodiment. As shown in Figure 8, the cooling plate 250 in this embodiment has a substantially cylindrical shape overall, and is positioned so that its axial direction is along the Y direction.

[0032] Figure 9 is a plan view showing the cavity screen 227. Figure 9 shows the cavity screen 227 as viewed in the -Y direction. As shown in Figure 9, the cavity screen 227 has the following gate openings 170: the first gate opening 171, the second gate opening 172, the third gate opening 173, the fourth gate opening 174, the fifth gate opening 175, and the sixth gate opening 176. More specifically, as shown in Figures 7 and 8, the cooling plate 250 has six cavities 252 that penetrate the cooling plate 250 in the Y direction, corresponding to each nozzle tip 245, and the openings on the +Y direction side of each cavity 252 form each gate opening 170. The +Y direction tip of each nozzle tip 245 is inserted into each cavity 252. In this embodiment, the first gate opening 171 to the sixth gate opening 176 are in communication with the same cavity 221.

[0033] As shown in Figure 9, in this embodiment, each gate opening 170 is arranged such that, when viewed along the -Y direction, each gate opening 170 constitutes one of the vertices of a roughly regular hexagon. The first gate opening 171 is located furthest to the -Z direction among the gate openings 170. The second gate opening 172 is located furthest to the +Z direction among the gate openings 170 and is the furthest from the first gate opening 171. The third gate opening 173 is located adjacent to the first gate opening 171 on the +Z and +X directions. The fourth gate opening 174 is located furthest from the third gate opening 173 among the gate openings 170. The fifth gate opening 175 is located adjacent to the third gate opening 173 on the +Z direction side of the third gate opening 173. The sixth gate opening 176 is located furthest from the fifth gate opening 175 among the gate openings 170.

[0034] In this embodiment, the first chip channel 246A shown in Figure 6 forms the first hot runner 181, and the second chip channel 246B forms the second hot runner 182. The first hot runner 181 injects the first molding material into the cavity 221 as the molding material through the first gate opening 171. The second hot runner 182 injects the second molding material into the cavity 221 as the molding material through the second gate opening 172. Similarly, the third chip channel 246C, the fourth chip channel 246D, the fifth chip channel 246E, and the sixth chip channel 246F form the third hot runner 183, the fourth hot runner 184, the fifth hot runner 185, and the sixth hot runner 186, respectively. The third hot runner 183 to the sixth hot runner 186 inject the third molding material to the sixth molding material into the cavity 221 via the third gate opening 173 to the sixth gate opening 176, respectively. In this embodiment, the first molding material to the sixth molding material are all the same material.

[0035] In this embodiment, each of the cavities 252 described above can also be described as an opening into which the first hot runner 181 to the sixth hot runner 186 can be inserted. Thus, the opening into which the first hot runner 181 can be inserted is also called the first opening, and the opening into which the second hot runner 182 can be inserted is also called the second opening.

[0036] Figure 10 shows a cross-section of XX in Figure 8. As shown in Figures 5, 8, and 10, the mold 220 is equipped with a cooling unit 260 for cooling the fixed mold 230. In this embodiment, the cooling unit 260 has a cooling channel 261 through which a cooling medium flows, and a refrigerant supply unit 269, shown in Figure 5, which supplies the cooling medium to the cooling channel 261. In this embodiment, the cooling channel 261 is formed in the cooling plate 250. More specifically, the cooling channel 261 is formed by spaces such as holes and grooves formed in the cooling plate 250. The refrigerant supply unit 269 is configured as a chiller that cools the cooling medium and circulates it through the cooling channel 261, and is connected to the inlet and outlet of the cooling channel 261. The refrigerant supply unit 269 is controlled by the control unit 500.

[0037] Figure 11 is a diagram illustrating the arrangement of the cooling channel 261 in this embodiment. Figure 11 schematically shows an excerpt of the cooling channel 261 formed within the cooling plate 250. Figure 11 also schematically shows the cavity area screen 227 and the first gate opening 171 to the sixth gate opening 176.

[0038] In this embodiment, the cooling unit 260 has a plurality of cooling channels 261. As shown in Figure 11, in this embodiment, the cooling unit 260 has a first cooling channel 262, a second cooling channel 263, and a third cooling channel 264 as cooling channels 261. Each cooling channel 261 has a different inlet and a different outlet, and is independent of each other and does not communicate with each other. More specifically, the first cooling channel 262 has a first inlet In1 and a first outlet Ex1. The second cooling channel 263 has a second inlet In2 and a second outlet Ex2. The third cooling channel 264 has a third inlet In3 and a third outlet Ex3. Furthermore, the inlet and outlet of each cooling channel 261 are connected to different refrigerant supply units 269. Each refrigerant supply unit 269 is individually controlled by the control unit 500.

[0039] Figure 12 is an explanatory diagram showing the manufacturing process of the cooling plate 250 in this embodiment. As shown in Figure 12, in this embodiment, the cooling plate 250 is manufactured by joining together multiple members having grooves and holes for forming cooling channels 261 by metal bonding, followed by the process of forming the aforementioned cavity 252 and grinding off unnecessary parts.

[0040] Figure 12 shows the first to fifth joining members J1 to J5 for forming the cooling plate 250. The first to third joining members J1 to J3 are made of stainless steel. The first joining member J1 has a substantially disc shape, and a groove Gr1 is formed on one of its faces. The second and third joining members J2 and J3 have a substantially cylindrical shape. The second joining member J2 has six holes HL1 for forming the cooling channel 261 and a hole Is1 for passing the fourth joining member J4 through. Holes Is1 and HL1 are through holes that penetrate the second joining member J2 along its axial direction. The third joining member J3 has six holes HL2 and a hole Is2 into which the tip of the fourth joining member J4 is inserted. Hole Is2 has its starting end on one bottom surface of the third joining member J3 and its ending end between the bottom surfaces of the third joining member J3. A groove Gr2 is formed at the end of hole Is2. Hole HL2 is a through hole that penetrates the third joining member J3 along its axial direction. The portion of the third joining member J3 in which the six holes HL2 are formed is removed in a grinding process after the first joining members J1 to the fifth joining members J5 are metal-joined.

[0041] The fourth joining member J4 and the fifth joining member J5 are made of copper. The fourth joining member J4 has a roughly hexagonal prism shape. The fourth joining member J4 has six holes HL3 formed therein for forming the cooling channel 261. The holes HL3 are through holes that penetrate the fourth joining member J4 along its axial direction. When the tip of the fourth joining member J4 is inserted into the hole Is2 of the third joining member J3 described above, two adjacent holes HL3 are connected by the groove Gr2 of the third joining member J3. In addition, a groove Gr3 is formed at the end of the fourth joining member J4 opposite to the tip, communicating with each hole HL3. The groove Gr3, together with the groove Gr1 formed on the first joining member J1, demarcates a part of the cooling channel 261. The fifth joining member J5 is formed in a disc shape with an opening in the center. The fifth joining member J5 has four holes HL4 formed therein for forming the cooling channel 261. Note that only three of the four holes HL4 are shown in Figure 12. Also, grooves not shown are formed on the unshown surface of the fifth joining member J5. The grooves formed in the fifth joining member J5, together with groove Gr1, demarcate a portion of the cooling channel 261.

[0042] As shown in Figure 12, the fourth joining member J4 and the fifth joining member J5 are stacked on the surface of the first joining member J1 where the groove Gr1 is formed. The second joining member J2 is stacked on the first joining member J1 and the fifth joining member J5 with the fourth joining member J4 passing through the hole Is1. The third joining member J3 is stacked on the second joining member J2 with the fourth joining member J4 inserted into the hole Is2. The first to fifth joining members J5 are stacked in this manner and metal-joined. As a result, as shown in Figure 10, the second and third copper members EL2 and EL3 are incorporated into the first stainless steel member EL1, which is formed by integrating the first to third joining members J1 and J3. The second member EL2 corresponds to the fourth joining member J4 incorporated into the first member EL1, and the third member EL3 corresponds to the fifth joining member J5 incorporated into the first member EL1. Furthermore, the grooves and holes formed in the first to fifth joining members J1 to J5 create cooling channels 261 in the cooling plate 250.

[0043] As shown in Figures 9 to 11, the end face 233, when viewed along the -Y direction, has a first region R1 having the portion of the end face 233 between the first gate opening 171 and the second gate opening 172, that is, the surface of the end face 233 between the first gate opening 171 and the second gate opening 172, and a second region R2 different from the first region R1. In this embodiment, the first region R1 has the surface between the first gate opening 171 and the second gate opening 172, as well as the surface between the first gate opening 171 and the third gate openings 173 to the sixth gate openings 176. More specifically, the first region R1 includes each midpoint between the first gate opening 171 and the second gate openings 172 to the sixth gate openings 176. An midpoint refers to the midpoint of a line segment connecting two points on the end face 233. As a result, the first region R1 in this embodiment includes the area inside the region connecting each gate opening 170, that is, the region inside the approximately regular hexagon formed by each gate opening 170. The second region R2 in this embodiment is the region that surrounds the outer perimeter of the first region R1 when viewed along the -Y direction.

[0044] The cooling unit 260 is configured such that its cooling capacity for the first region R1 is higher than its cooling capacity for the second region R2. In this embodiment, when projected onto a plane perpendicular to the Y direction, the portion of the cooling channel 261 that overlaps with the first region R1 is more densely arranged than the portion of the cooling channel 261 that overlaps with the second region R2, thereby achieving a higher cooling capacity for the first region R1 than for the second region R2. More specifically, when projected onto a plane perpendicular to the Y direction, the cooling channel 261 is arranged such that the ratio of the area of ​​the portion of the cooling channel 261 that overlaps with the first region R1 to the area of ​​the first region R1 is higher than the ratio of the area of ​​the portion of the cooling channel 261 that overlaps with the second region R2 to the area of ​​the second region R2. As a result, in this embodiment, when the fixed type 230 is cooled by the cooling unit 260, the maximum temperature in the first region R1 is lower than the maximum temperature in the second region R2. In the following, the degree of density of cooling channels 261 in the first region R1 and the second region R2 will also be referred to as the "density" of cooling channels 261 in that region. The density of cooling channels 261 in a given region can be increased, for example, by increasing the number of cooling channels 261 in the portion of the cavity plate 254 that overlaps with that region, or by increasing the cross-sectional area of ​​the channels.

[0045] In this embodiment, the cooling channels 261 are arranged such that the density of cooling channels 261 in the portion of the cavity plate 254 that overlaps with the first region R1 when viewed along the Y direction is higher than the density of cooling channels 261 in the portion that overlaps with the second region R2. The density of cooling channels 261 in a given portion refers to the ratio of the volume of cooling channels 261 arranged in that portion to the volume of that portion. The density of cooling channels 261 in a given portion can be increased, for example, by increasing the number of cooling channels 261 in that portion or by increasing the cross-sectional area of ​​the channels.

[0046] In this embodiment, of the portion of the cooling unit 260 of the fixed type 230 that is cooled, at least a portion of the portion that overlaps with the first region R1 is formed of a material having a higher thermal conductivity than the material forming the portion that overlaps with the second region R2. More specifically, in this embodiment, as shown in Figure 10, the portion P2 of the cooling plate 250 that overlaps with the second region R2 is formed by the first material EL1, that is, stainless steel. The portion P1 of the cooling plate 250 that overlaps with the first region R1 has a portion formed by the first material EL1 and a portion formed by the second material EL2. In other words, portion P1 has a portion formed of stainless steel and a portion formed of copper having a higher thermal conductivity than stainless steel. This makes it easier for portion P1 to be cooled by the cooling medium in the cooling channel 261. In particular, in this embodiment, since the cooling channel 261 is formed in the second material EL2, portion P1 is cooled even more easily.

[0047] As shown in Figure 7, in this embodiment, the cavity screen 227 has a first surface 228 and a second surface 229. The second surface 229 refers to the surface of the cavity screen 227 that is closer to the movable mold 255 when clamped than the first surface 228.

[0048] Figure 13 is a diagram illustrating the relationship between the shape of the molded product Pr and the arrangement of the cooling channel 261 in this embodiment. The upper part of Figure 13 shows the cooling channel 261. The middle part of Figure 13 shows the cooling channel 261p projected onto the cavity area screen 227. The lower part of Figure 13 shows the molded product Pr formed by the mold 220 in this embodiment. As shown in the lower part of Figure 13, the molded product Pr is a disc-shaped part with an opening in the center, and the outer edge portion Eg of the molded product Pr has a smaller thickness compared to the portion inside the outer edge portion Eg. Therefore, as shown in Figure 7 and the middle part of Figure 13, when viewed along the Z direction, the outer edge portion of the cavity area screen 227 corresponds to the second surface 229, and the portion inside the second surface 229 corresponds to the first surface 228.

[0049] The cooling section 260 is configured such that, when viewed along the Z direction, the cooling capacity for the first surface 228 is higher than the cooling capacity for the second surface 229. As shown in the middle section of Figure 13, in this embodiment, when projected onto a plane perpendicular to the Y direction, the cooling channels 261p are arranged more densely on the first surface 228 than on the second surface 229, thereby achieving a higher cooling capacity for the first surface 228 than for the second surface 229.

[0050] According to the injection molding apparatus 100 of the first embodiment described above, the end face 233 of the fixed mold 230 has, when viewed along the Y direction, a first region R1 having the surface between the first gate opening 171 and the second gate opening 172, and a second region R2 different from the first region R1. The cooling unit 260 is configured such that the cooling capacity for the first region R1 is higher than the cooling capacity for the second region R2. As a result, the cooling capacity of the cooling unit 260 for the first region R1 is higher than the cooling capacity for the second region R2, so the surface between the first gate opening 171 and the second gate opening 172 is cooled intensively. Therefore, the area of ​​the end face 233 of the fixed mold 230 where the hot runners are in close proximity can be properly cooled, and the impact on the quality of the molded product can be suppressed. More specifically, for example, whitening and deformation of the molded product due to the molded product not being sufficiently solidified during mold opening or demolding can be suppressed. Furthermore, if the end face 233 of the fixed mold 230, particularly the cavity section screen 227, is cooled uniformly, the temperature of the molding material injected into the cavity 221 may drop excessively, potentially leading to a decrease in molding quality. In this embodiment, the first region R1 and the second region R2 are cooled with different cooling capacities, thereby suppressing such a decrease in molding quality.

[0051] Furthermore, in this embodiment, the cooling unit 260 has cooling channels 261 through which the cooling medium flows, and when projected onto a plane perpendicular to the Y direction, the cooling channels 261 are arranged more densely in the first region R1 than in the second region R2. This makes it easier for the cooling medium to concentrate near the first region R1, thereby promoting heat exchange between the fixed type 230 and the cooling medium near the first region R1. As a result, the cooling capacity for the first region R1 can be made higher than the cooling capacity for the second region R2 by a simple method.

[0052] Furthermore, in this embodiment, the cooling unit 260 has a plurality of cooling channels 261, and each cooling channel 261 has a different inlet and a different outlet. This allows the length from the inlet to the outlet of the cooling channel 261 to be shortened compared to, for example, the case where only a single cooling channel 261 is provided, thereby suppressing the occurrence of a temperature difference between the inlet and outlet of the cooling channel 261. In addition, for example, the flow rate and temperature of the cooling medium in each cooling channel 261 can be controlled individually. Therefore, the possibility of cooling the fixed type 230 more appropriately by the cooling unit 260 is increased.

[0053] Furthermore, in this embodiment, the first gate opening 171 and the second gate opening 172 communicate with the same cavity 221. In this configuration, the distance between the first gate opening 171 and the second gate opening 172 tends to be shorter compared to, for example, the case where the first gate opening 171 and the second gate opening 172 communicate with different cavities. Therefore, the area between the first gate opening 171 and the second gate opening 172 tends to become hotter, but the cooling unit 260 described above can effectively cool this area between the first gate opening 171 and the second gate opening 172. Thus, it is possible to effectively suppress any impact on the quality of the molded product.

[0054] Furthermore, in this embodiment, when viewed along the Y direction, at least a portion of the portion of the fixed type 230 that is cooled by the cooling section 260 that overlaps with the first region R1 is made of a material having a higher thermal conductivity than the material forming the portion that overlaps with the second region R2. Therefore, the first region R1 can be cooled more efficiently by the cooling section 260. In addition, the cooling capacity for the first region R1 can be made higher than the cooling capacity for the second region R2 by a simple method.

[0055] Furthermore, in this embodiment, the cavity screen 227 has a first surface 228 and a second surface 229 which is closer to the movable mold 255 when clamped than the first surface 228, and the cooling unit 260 is configured such that the cooling capacity for the first surface 228 is higher than the cooling capacity for the second surface 229. This makes it possible to suppress a decrease in the temperature of the molding material located in the cavity 221 at locations where the distance in the Y direction between the fixed mold 230 and the movable mold 255 is smaller. Therefore, it is possible to suppress a decrease in the molding quality of molded products having thin-walled portions.

[0056] B. Second Embodiment: Figure 14 is a diagram illustrating the arrangement of the cooling channels 261b of the cooling unit 260b in the second embodiment. Figure 14 shows the cavity screen 227 of the cooling plate 250b as viewed in the -Y direction. Figure 14 schematically shows the positions of the cooling channels 261b in the X and Z directions. In this embodiment, the control unit 500 controls the cooling unit 260b so that the cooling capacity for the first region R1 is higher than the cooling capacity for the second region R2. The configuration of the injection molding apparatus 100 and the mold 220 is the same as in the first embodiment unless otherwise described.

[0057] In this embodiment, the cooling section 260b includes a first cooling section 265 for cooling a first region R1 and a second cooling section 267 for cooling a second region R2. In this embodiment, the first cooling section 265 includes a fourth cooling channel 266 arranged to overlap the first region R1 when viewed along the Y direction, and a chiller (not shown) connected to the inlet and outlet of the fourth cooling channel 266. The second cooling section 267 includes a fifth cooling channel 268 arranged to overlap the second region R2 when viewed along the -Y direction, and a chiller (not shown) connected to the inlet and outlet of the fifth cooling channel 268. The inlet and outlet of the fourth cooling channel 266 and the inlet and outlet of the fifth cooling channel 268 are different. More specifically, the fourth cooling channel 266 has a fourth inlet In4 and a fourth outlet Ex4. The fifth cooling channel 268 has a fifth inlet In5 and a fifth outlet Ex5. Furthermore, the control unit 500 is configured to control the first cooling unit 265 and the second cooling unit 267 individually. In this embodiment, the density of the fourth cooling channel 266 in the first region R1 and the density of the fifth cooling channel 268 in the second region R2 are approximately the same.

[0058] In this embodiment, the control unit 500 sets the output of the chiller of the first cooling unit 265 to be higher than the output of the chiller of the second cooling unit 267, thereby making the cooling capacity for cooling the first region R1 higher than the cooling capacity for cooling the second region R2.

[0059] According to the second embodiment described above, the control unit 500 individually controls the first cooling unit 265, which cools the first region R1, and the second cooling unit 267, which cools the second region R2, so that the cooling capacity for the first region R1 is higher than the cooling capacity for the second region R2. Therefore, the cooling capacity for the first region R1 can be made higher than the cooling capacity for the second region R2 by a simple method.

[0060] In other embodiments, for example, as described in the first embodiment, the density of the cooling channels 261b in the first region R1 may be made higher than the density of the cooling channels 261b in the second region R2, and then, as described above, the first cooling unit 265 and the second cooling unit 267 may be individually controlled so that the cooling capacity for the first region R1 is higher than the cooling capacity for the second region R2.

[0061] Furthermore, in the second embodiment, the control unit 500 controlled the output of the first cooling unit 265 to be higher than the output of the second cooling unit 267, but in other embodiments, it is not necessary to control the outputs of the first cooling unit 265 and the second cooling unit 267 in this way. For example, if the first cooling unit 265 and the second cooling unit 267 have a temperature adjustment unit configured by a heater, and the temperature of the refrigerant supplied to the fourth cooling channel 266 and the fifth cooling channel 268 is adjusted by the temperature adjustment unit, the cooling capacity for cooling the first region R1 may be made higher than the cooling capacity for cooling the second region R2 by lowering the output of the temperature adjustment unit of the first cooling unit 265 to be lower than the output of the temperature adjustment unit of the second cooling unit 267.

[0062] C. Other embodiments: (C-1) In the above embodiment, the cooling channel 261 of the cooling section 260 may be configured to be separable. In this case, the cooling channel 261 may be formed by a plurality of members configured to be removable from one another. More specifically, for example, instead of joining the first joining members J1 to the fifth joining members J5 described in Figure 13 with metal, the cooling channel 261 may be configured to be separable by fixing them to each other with fasteners such as bolts to form a cooling plate 250. In this case, it is preferable that the joints of grooves and holes formed in each member be sealed to be liquid-tight so that the liquid-tightness of the cooling channel 261 is ensured when each member is fixed to each other. By configuring the cooling channel 261 to be separable in this way, the inside of the cooling channel 261 can be cleaned more easily, thereby improving the maintainability of the cooling channel 261.

[0063] (C-2) In the above embodiment, the cooling channel 261 of the cooling section 260 may be formed by three-dimensional molding. In this case, for example, a three-dimensional object with the cooling channel 261 formed on it may be manufactured by a material extrusion (ME) method, and this three-dimensional object may be used as a cooling plate 250. In this case, for example, by molding the three-dimensional object using a metal material or a ceramic material as the main material, a cooling plate 250 with excellent strength and heat resistance can be manufactured. "Main material" means the central material that forms the shape of the three-dimensional object, and means a material that accounts for 50% by weight or more in the three-dimensional object. More specifically, for example, a three-dimensional object can be manufactured by plasticizing a material containing metal powder or ceramic powder and a binder, and then extruding the generated material onto a stage. The manufactured three-dimensional object may be used as a cooling plate 250 after undergoing sintering and polishing. Furthermore, instead of material extrusion, stereolithography or inkjet printing methods may be used as the three-dimensional manufacturing method.

[0064] By forming the cooling channel 261 using three-dimensional fabrication, the cooling channel 261 can be formed more easily, even if it has a complex channel shape. Furthermore, it is possible to form an integrally constructed cooling channel 261 more easily. For example, when forming a cooling channel 261 in a columnar member such as a cylinder, as in the cooling plate 250 of the above embodiment, it is usually difficult to change the direction in which the cooling channel 261 extends within the member multiple times in directions that intersect the axial and planar directions of the member. Moreover, it is even more difficult to form a cooling channel 261 with such a channel shape integrally. Three-dimensional fabrication makes it easier to form such cooling channels 261.

[0065] (C-3) In the above embodiment, each gate opening 170 is arranged such that, when viewed along the -Y direction, each gate opening 170 constitutes a vertex of a substantially regular hexagon. However, the gate openings 170 do not have to be arranged in this way. For example, each gate opening 170 may be arranged so that, when viewed along the -Y direction, each gate opening 170 constitutes a vertex of another polygon, or they may be arranged in a straight line. Also, in the above embodiment, the first region R1 includes the portion between the first gate opening 171 and the second gate opening 172, as well as the portion between the first gate opening 171 and the third gate openings 173 to the sixth gate openings 176, but it does not have to include the portion between the first gate opening 171 and the third gate openings 173 to the sixth gate openings 176. Also, in the above embodiment, the second gate opening 172 is located furthest from the first gate opening 171 among the gate openings 170, but it does not have to be arranged in this way; for example, it may be located adjacent to the first gate opening 171. Furthermore, in the above embodiment, six gate openings 170 are provided in the fixed type 230, but the number of gate openings 170 provided in the fixed type 230 may be two to five, or seven or more.

[0066] (C-4) In the above embodiment, the first molding material and the second molding material are the same material, but they may be different materials. Similarly, the third to sixth molding materials may be the same material as the first and second molding materials, or they may be different materials. In this case, for example, the injection molding apparatus 100 may be equipped with a plurality of different injection units 140 for injecting each molding material into the cavity 221 through each hot runner and each gate opening 170.

[0067] (C-5) In the above embodiment, the cooling unit 260 has a plurality of cooling channels 261, and each cooling channel 261 has a different inlet and a different outlet. In contrast, for example, the inlets and outlets of each cooling channel 261 may be common. Alternatively, the cooling unit 260 may have only a single cooling channel 261.

[0068] (C-6) In the above embodiment, the cooling unit 260 has a cooling channel 261, but it does not have to have a cooling channel 261. In this case, the cooling unit 260 may have, for example, a Peltier element and a power supply that supplies current to the Peltier element. In this case, for example, the Peltier element may be placed in the cooling plate 250, and power may be supplied to the Peltier element from the current supply unit such that the surface close to the end face 233 of the Peltier element absorbs heat and the surface far from the end face 233 of the Peltier element dissipates heat. In this case, to promote heat dissipation from the surface far from the end face 233 of the Peltier element, for example, a heat sink or the like may be provided on the cooling plate 250.

[0069] If the cooling capacity of the cooling unit 260 having a Peltier element for the first region R1 is to be higher than the cooling capacity for the second region R2, for example, when projected onto a plane perpendicular to the clamping direction, the Peltier elements may be arranged more densely in the first region R1 than in the second region R2. Alternatively, Peltier elements may be arranged in the first region R1, but not in the second region R2. Furthermore, as described in the second embodiment, the control unit 500 may individually control the first cooling unit 265 having a Peltier element arranged in the first region R1 and the second cooling unit 267 having a Peltier element arranged in the second region R2, so that the cooling capacity for the first region R1 is higher than the cooling capacity for the second region R2. More specifically, in this case, the control unit 500 may, for example, set the output of the power supply that supplies current to the Peltier element of the first cooling unit 265 to be higher than the output of the power supply that supplies current to the Peltier element of the second cooling unit 267.

[0070] (C-7) In the above embodiment, the first gate opening 171 and the second gate opening 172 communicate with the same cavity 221, but they do not have to communicate with the same cavity 221. For example, if a plurality of cavities 221 are partitioned by a fixed mold 230 and a molding mold 220, the first gate opening 171 and the second gate opening 172 may each communicate with different cavities 221. Similarly, the third gate opening 173 to the sixth gate opening 176 may each communicate with the same cavity 221 as the first gate opening 171 and the second gate opening 172, or they may communicate with different cavities 221.

[0071] (C-8) In the above embodiment, when viewed along the clamping direction, at least a portion of the member cooled by the cooling section 260 of the fixed mold 230 that overlaps with the first region R1 is formed of a member having a higher thermal conductivity than the member forming the portion P2 that overlaps with the second region R2. In contrast, portions P1 and P2 do not necessarily have to be formed of such members; for example, portions P1 and P2 may be formed of members having the same thermal conductivity, or the thermal conductivity of the member forming portion P1 may be lower than that of the member forming portion P2.

[0072] (C-9) In the above embodiment, the cooling unit 260 is configured such that the cooling capacity for the first surface 228 of the cavity screen 227 is higher than the cooling capacity for the second surface 229. In contrast, the cooling unit 260 may be configured such that the cooling capacity for the first surface 228 and the cooling capacity for the second surface 229 are the same, or the cooling capacity for the first surface 228 may be lower than the cooling capacity for the second surface 229.

[0073] (C-10) In the above embodiment, the plasticizing section 110 has a flat screw 111. Alternatively, the plasticizing section 110 may have an inline screw instead of the flat screw 111. In this case, the barrel is formed in a cylindrical shape to house the inline screw and is sometimes called a cylinder.

[0074] (C-11) In the above embodiment, the injection molding apparatus 100 is a horizontal injection molding apparatus, but it may also be a vertical injection molding apparatus. In addition, the injection unit 140 and the clamping device 130 may be arranged vertically.

[0075] D. Other forms: This disclosure is not limited to the embodiments described above, and can be implemented in various forms without departing from its spirit. For example, this disclosure can also be implemented in the following forms. The technical features in the embodiments described below that correspond to the technical features in each of the forms described below can be replaced or combined as appropriate in order to solve some or all of the problems of this disclosure, or to achieve some or all of the effects of this disclosure. Furthermore, if such technical features are not described as essential in this specification, they can be deleted as appropriate.

[0076] (1) According to a first embodiment of the present disclosure, an injection molding apparatus is provided. The injection molding apparatus comprises a fixed mold having a first gate opening and a second gate opening different from the first gate opening; a movable mold configured to be clamped to the fixed mold; a first hot runner for injecting a first molding material through the first gate opening into a cavity partitioned by the fixed mold and the movable mold; a second hot runner for injecting a second molding material through the second gate opening into the cavity; and a cooling unit for cooling the fixed mold. The end face of the fixed mold facing the movable mold has, when viewed along the clamping direction, a first region having a surface located between the first gate opening and the second gate opening, and a second region different from the first region. The cooling unit is configured such that the cooling capacity for the first region is higher than the cooling capacity for the second region. In this configuration, the cooling capacity of the cooling section for the first region is higher than that for the second region, so the surface between the first gate opening and the second gate opening is cooled intensively. As a result, the area of ​​the fixed mold end face where the hot runners are in close proximity can be properly cooled, and the impact on the quality of the molded product can be suppressed.

[0077] (2) In the above configuration, the cooling section has cooling channels through which a cooling medium flows, and when projected onto a plane perpendicular to the mold clamping direction, the cooling channels may be more densely arranged in the first region than in the second region. With this configuration, the cooling medium tends to concentrate near the first region, promoting heat exchange between the fixed mold and the cooling medium near the first region. Therefore, the cooling capacity for the first region can be made higher than the cooling capacity for the second region by a simple method.

[0078] (3) In the above configuration, the cooling unit may have a plurality of cooling channels through which a cooling medium flows, and each of the cooling channels may have different inlets and different outlets. With this configuration, the length from the inlet to the outlet of the cooling channel can be shortened compared to the case where only a single cooling channel is provided, so that a temperature difference between the inlet and outlet of the cooling channel can be suppressed. Also, for example, the flow rate and temperature of the cooling medium in each cooling channel can be controlled individually. Therefore, the possibility of the cooling unit cooling the fixed type more appropriately is increased.

[0079] (4) In the above embodiment, the cooling unit is provided with a control unit for controlling the cooling unit, and the cooling unit has a first cooling unit for cooling the first region and a second cooling unit for cooling the second region, and the control unit may individually control the first cooling unit and the second cooling unit so that the cooling capacity for the first region is higher than the cooling capacity for the second region. With this embodiment, the cooling capacity for the first region can be made higher than the cooling capacity for the second region by a simple method.

[0080] (5) In the above configuration, the first gate opening and the second gate opening may communicate with the same cavity. In such a configuration, for example, the portion between the first gate opening and the second gate opening tends to become hotter compared to the case where the first gate opening and the second gate opening communicate with different cavities, but the cooling unit can effectively cool this portion between the first gate opening and the second gate opening. Therefore, it is possible to effectively suppress any impact on the quality of the molded product.

[0081] (6) In the above embodiment, when viewed along the clamping direction, at least a portion of the portion of the fixed mold that is cooled by the cooling unit and overlaps with the first region may be made of a material having a higher thermal conductivity than the material forming the portion that overlaps with the second region. With this embodiment, the first region can be cooled more efficiently by the cooling unit. In addition, the cooling capacity for the first region can be made higher than the cooling capacity for the second region by a simple method.

[0082] (7) In the above embodiment, the end face that partitions the cavity has a first face and a second face which is closer to the movable mold when clamped than to the first face, and the cooling unit may be configured such that the cooling capacity for the first face is higher than the cooling capacity for the second face. With this embodiment, it is possible to suppress the decrease in temperature of the molding material in the cavity that is located at a point where the distance between the fixed mold and the movable mold in the clamping direction is smaller. As a result, it is possible to suppress a decrease in the molding quality of molded products having thin-walled portions.

[0083] (8) A second embodiment of the present disclosure provides a mold. The mold includes a fixed mold having a first gate opening and a second gate opening different from the first gate opening; a movable mold; a first opening configured to allow insertion of a first hot runner for injecting a first molding material through the first gate opening into a cavity partitioned by the fixed mold and the movable mold; a second opening configured to allow insertion of a second hot runner for injecting a second molding material through the second gate opening into the cavity; and a cooling section for cooling the fixed mold. The end face of the fixed mold closest to the movable mold has, when viewed along the mold clamping direction, a first region having a surface of the end face located between the first gate opening and the second gate opening, and a second region different from the first region. The cooling section is configured such that the cooling capacity for the first region is higher than the cooling capacity for the second region. [Explanation of Symbols]

[0084] 20...Base, 30...Hopper, 100...Injection molding machine, 101...Housing section, 110...Plasticizing section, 111...Flat screw, 112...Barrel, 113...Heater, 114...Nozzle, 116...Communication hole, 118...Drive motor, 120...Injection control mechanism, 121...Injection cylinder, 122...Plunger, 123...Plunger drive unit, 124...Check valve, 130...Clamping device, 131...Mold drive unit, 132...Ball screw, 140...Injection unit, 161...Internal flow path, 163...Thrust bearing, 164...Extruder plate, 166...Ejector 167...Support plate, 168...Support rod, 169...Spring, 170...Gate opening, 171...First gate opening, 172...Second gate opening, 173...Third gate opening, 174...Fourth gate opening, 175...Fifth gate opening, 176...Sixth gate opening, 181...First hot runner, 182...Second hot runner, 183...Third hot runner, 184...Fourth hot runner, 185...Fifth hot runner, 186...Sixth hot runner, 201...Groove forming surface, 202...Groove, 203...Material input port, 204...Protruding ridge, 205...Center Section, 211... Guide groove, 212... Opposing surface, 220... Molding die, 221... Cavity, 227... Cavity section screen, 228... First surface, 229... Second surface, 230... Fixed die, 233... End face, 235... Sprue bush, 236... Sprue, 237... Locating ring, 240... Manifold section, 241... Manifold flow path, 242... First branching point, 243... Second branching point, 244... Cartridge heater, 245... Nozzle tip, 246... Tip flow path, 246A... First tip flow path, 246B... Second tip flow path, 246C... Third tip flow path Pathway, 246D...4th chip channel, 246E...5th chip channel, 246F...6th chip channel, 248...valve pin, 249...pin drive unit, 250...cooling plate, 251...plate end face, 252...cavity, 255...movable type, 260, 260b...cooling unit, 261, 261b...cooling channel, 262...1st cooling channel, 263...2nd cooling channel, 264...3rd cooling channel, 265...1st cooling unit, 266...4th cooling channel, 267...2nd cooling unit, 268...5th cooling channel, 269...refrigerant supply unit, 500...control unit, R1...1st region, R2...2nd region

Claims

1. A fixed type having a first gate opening and a second gate opening different from the first gate opening, A movable mold configured to be clamped to the aforementioned fixed mold, Within the cavity partitioned by the fixed mold and the movable mold, a first hot runner for injecting the first molding material through the first gate opening is provided. Within the cavity, a second hot runner is provided for injecting the second molding material through the second gate opening, The unit comprises a cooling section for cooling the aforementioned fixed type, The end face of the fixed mold facing the movable mold has, when viewed along the mold clamping direction, a first region including the center of the end face and a second region surrounding the outer periphery of the first region, and the first region includes the surface of the end face located between the first gate opening and the second gate opening. The cooling unit is configured such that its cooling capacity for the first region is higher than its cooling capacity for the second region. When viewed along the clamping direction, at least a portion of the portion of the fixed mold that is cooled by the cooling unit that overlaps with the first region is formed of a material having a higher thermal conductivity than the material forming the portion that overlaps with the second region. Injection molding equipment.

2. An injection molding apparatus according to claim 1, The cooling unit has a cooling channel through which a cooling medium flows, An injection molding apparatus in which, when projected onto a plane perpendicular to the clamping direction, the cooling channels are arranged more densely in the first region than in the second region.

3. An injection molding apparatus according to claim 1, The cooling unit has a plurality of cooling channels through which a cooling medium flows, An injection molding apparatus, wherein each of the cooling channels has a different inlet and a different outlet.

4. An injection molding apparatus according to claim 1, The cooling unit is equipped with a control unit that controls the cooling unit, The cooling unit comprises a first cooling unit for cooling the first region and a second cooling unit for cooling the second region. The control unit individually controls the first cooling unit and the second cooling unit so that the cooling capacity for the first region is higher than the cooling capacity for the second region, in an injection molding apparatus.

5. An injection molding apparatus according to claim 1, An injection molding apparatus in which the first gate opening and the second gate opening communicate with the same cavity.

6. A fixed mold having a first gate opening and a second gate opening different from the first gate opening, A movable mold configured to be clamped to the aforementioned fixed mold, Within the cavity partitioned by the fixed mold and the movable mold, a first hot runner for injecting the first molding material through the first gate opening is provided. Within the cavity, a second hot runner is provided for injecting the second molding material through the second gate opening, The unit comprises a cooling section for cooling the aforementioned fixed type, The end face of the fixed mold facing the movable mold has, when viewed along the mold clamping direction, a first region including the center of the end face and a second region surrounding the outer periphery of the first region, and the first region includes the surface of the end face located between the first gate opening and the second gate opening. The cooling unit is configured such that its cooling capacity for the first region is higher than its cooling capacity for the second region. Of the end faces, the face that demarcates the cavity has a first face and a second face whose distance from the movable mold when clamped is shorter than that from the first face. An injection molding apparatus in which the cooling unit is configured such that the cooling capacity for the first surface is higher than the cooling capacity for the second surface.

7. A fixed type having a first gate opening and a second gate opening different from the first gate opening, Movable type, A first opening is configured to allow insertion of a first hot runner into which a first molding material is injected through the first gate opening, within a cavity partitioned by the fixed mold and the movable mold, A second opening is provided within the cavity, into which a second hot runner for injecting a second molding material through the second gate opening can be inserted. The unit comprises a cooling section for cooling the aforementioned fixed type, The end face of the fixed mold closest to the movable mold has, when viewed along the clamping direction, a first region including the center of the end face and a second region surrounding the outer periphery of the first region, and the first region includes the end face located between the first gate opening and the second gate opening. The cooling unit is configured such that its cooling capacity for the first region is higher than its cooling capacity for the second region. When viewed along the clamping direction, at least a portion of the portion of the fixed mold that is cooled by the cooling unit that overlaps with the first region is formed of a material having a higher thermal conductivity than the material forming the portion that overlaps with the second region. Molding mold.

8. A fixed mold having a first gate opening and a second gate opening different from the first gate opening, Movable type, A first opening is configured to allow insertion of a first hot runner into which a first molding material is injected through the first gate opening, within a cavity partitioned by the fixed mold and the movable mold, A second opening is provided within the cavity, into which a second hot runner for injecting a second molding material through the second gate opening can be inserted. The unit comprises a cooling section for cooling the aforementioned fixed type, The end face of the fixed mold closest to the movable mold has, when viewed along the clamping direction, a first region including the center of the end face and a second region surrounding the outer periphery of the first region, and the first region includes the end face located between the first gate opening and the second gate opening. The cooling unit is configured such that its cooling capacity for the first region is higher than its cooling capacity for the second region. Of the end faces, the face that demarcates the cavity has a first face and a second face whose distance from the movable mold when clamped is shorter than that from the first face. The cooling unit is configured such that its cooling capacity for the first surface is higher than its cooling capacity for the second surface. Molding mold.

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