Mold device and injection molding system

Abstract

The invention provides a mold device and an injection molding system, and provides a technology capable of reducing cooling unevenness of the mold device in the direction orthogonal to the mold clamping direction and reducing shrinkage unevenness of a molded product in the direction orthogonal to the mold clamping direction. The fixed mold is provided with: a first mold part which is in contact with the movable mold during mold clamping and forms a part of the wall surface of the cavity space; a first cooling part, the temperature of which is adjusted to be lower than the temperature of the first mold part when the molding material is filled; and a first support part that supports one of the first cooling part and the first mold part so as to be capable of moving relative to the other of the first cooling part and the first mold part. The first cooling unit and the first mold unit are relatively movable between a position where the first cooling unit and the first mold unit are separated from each other and a position where the first cooling unit and the first mold unit are in contact with each other in both a mold opening direction and a mold closing direction.

Description

[0001] This application claims priority based on Japanese Patent Application No. 2024-069341 filed on April 22, 2024. The entire contents of this Japanese application are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to a mold device and an injection molding system. BACKGROUND

[0003] The device described in Patent Literature 1 is provided with: a mold composed of a fixed mold and a movable mold; a temperature adjustment block for heating or cooling the mold; and a pressing mechanism of the temperature adjustment block. The temperature adjustment block is provided with a pair of temperature adjustment blocks in a direction orthogonal to a mold clamping direction. The pressing mechanism presses (causes to be in close contact with) the temperature adjustment blocks to the mold in a direction orthogonal to the mold clamping direction. By controlling the pressing force (the close contact force), the temperature of the mold can be controlled.

[0004] Patent Literature 1: Japanese Patent Application Publication No. 10-315292

[0005] The mold device is provided with a fixed mold and a movable mold, and a cavity space is formed between the fixed mold and the movable mold at the time of mold clamping. The cavity space is a space in which a molding material that is heated in advance is filled. By cooling the molding material in the cavity space to solidify it, a molded product can be obtained.

[0006] If the temperature of the mold device is too low, the flowability of the molding material at the time of filling is poor, and it is difficult to transfer the shape and size of the cavity space to the molded product. Therefore, if the temperature of the mold device is too low, the mold device has poor transferability. On the other hand, if the temperature of the mold device is too high, the molding material is difficult to cool in the cavity space. Therefore, the cooling time until the molding material solidifies to the extent that it can be taken out of the mold device is too long, and the production efficiency of the molded product is poor.

[0007] In order to improve the transferability of the mold device and shorten the cooling time, it can be considered to use the technology described in Patent Literature 1. However, in Patent Literature 1, since the temperature adjustment blocks are pressed (caused to be in close contact with) to the mold in a direction orthogonal to the mold clamping direction, uneven cooling of the mold in the direction orthogonal to the mold clamping direction is likely to occur. As a result, uneven shrinkage of the molded product in the direction orthogonal to the mold clamping direction is likely to occur. In addition, the mold clamping direction coincides with the mold opening and closing direction.

[0008] Most molded articles have a dimension in a direction orthogonal to a direction of mold clamping that is larger than a dimension in the direction of mold clamping. For example, lenses, connectors, lids of containers, and the like have a dimension in a direction orthogonal to a direction of mold clamping that is larger than a dimension in the direction of mold clamping. Therefore, uneven shrinkage of a molded article in a direction orthogonal to a direction of mold clamping can cause a decrease in dimensional accuracy of the molded article. SUMMARY

[0009] One embodiment of the present application provides a technology capable of reducing uneven cooling of a mold device in a direction orthogonal to a direction of mold clamping and capable of reducing uneven shrinkage of a molded article in a direction orthogonal to a direction of mold clamping.

[0010] A mold device according to one embodiment of the present application includes a stationary mold and a movable mold. A cavity space is formed between the stationary mold and the movable mold at the time of mold clamping. The cavity space is a space for filling a molded material that is heated in advance. The stationary mold includes a first mold portion that contacts the movable mold at the time of mold clamping and forms part of a wall surface of the cavity space, a first cooling portion whose temperature is adjusted to be lower than a temperature of the first mold portion at the time of filling the molded material, and a first support portion that supports one of the first cooling portion and the first mold portion so as to be relatively movable with respect to the other. The first cooling portion and the first mold portion are relatively movable in two directions, i.e., a mold opening direction and a mold closing direction, between a position at which the first cooling portion and the first mold portion are apart from each other and a position at which the first cooling portion and the first mold portion contact each other. The movable mold includes a second mold portion that contacts the stationary mold at the time of mold clamping and forms part of a wall surface of the cavity space, a second cooling portion whose temperature is adjusted to be lower than a temperature of the second mold portion at the time of filling the molded material, and a second support portion that supports one of the second cooling portion and the second mold portion so as to be relatively movable with respect to the other. The second cooling portion and the second mold portion are relatively movable in the two directions, i.e., the mold opening direction and the mold closing direction, between a position at which the second cooling portion and the second mold portion are apart from each other and a position at which the second cooling portion and the second mold portion contact each other.

[0011] EFFECT OF THE INVENTION

[0012] According to one embodiment of the present application, it is possible to reduce uneven cooling of a mold device in a direction orthogonal to a direction of mold clamping and to reduce uneven shrinkage of a molded article in a direction orthogonal to a direction of mold clamping. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 FIG. 1 is a view that shows a state of an injection molding machine at the time of mold opening according to one embodiment of the present application.

[0014] Figure 2 FIG. 2 is a view that shows a state of the injection molding machine at the time of mold clamping according to one embodiment of the present application.

[0015] Figure 3 (A) is a sectional view showing a state at the start of filling of the mold device according to one embodiment, Figure 3 (B) is a sectional view showing a state at the end of filling of the mold device according to one embodiment, Figure 3 (C) is a sectional view showing a state at the time of cooling of the mold device according to one embodiment.

[0016] Figure 4 (A) is a sectional view showing a state at the start of filling of the mold device according to the first modification, Figure 4 (B) is a sectional view showing a state at the end of filling of the mold device according to the first modification, Figure 4 (C) is a sectional view showing a state at the time of cooling of the mold device according to the first modification.

[0017] Figure 5 (A) is a sectional view showing a state at the end of filling of the mold device according to the second modification, Figure 5 (B) is a sectional view showing a state at the time of cooling of the mold device according to the second modification.

[0018] In the drawing: 800 - mold device, 801 - cavity space, 810 - fixed mold, 811 - first mold portion, 812 - first cooling portion, 813 - first support portion, 820 - movable mold, 821 - second mold portion, 822 - second cooling portion, 823 - second support portion. DETAILED DESCRIPTION

[0019] Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings. In addition, in each drawing, the same or corresponding structures are sometimes denoted by the same symbol, and the description will be omitted.

[0020] (injection molding machine)

[0021] Figure 1 is a view showing a state at the end of mold opening of the injection molding machine according to one embodiment. Figure 2 is a view showing a state at the time of mold closing of the injection molding machine according to one embodiment. In the present specification, the X-axis direction, the Y-axis direction, and the Z-axis direction are directions perpendicular to each other. The X-axis direction and the Y-axis direction represent horizontal directions, and the Z-axis direction represents a vertical direction. When the mold closing device 100 is horizontal, the X-axis direction is a mold opening and closing direction, and the Y-axis direction is a width direction of the injection molding machine 10. The negative side of the Y-axis direction is referred to as an operation side, and the positive side of the Y-axis direction is referred to as the opposite side of the operation side.

[0022] AsFigures 1-2 As shown in the figure, the injection molding machine 10 has a clamp device 100 of an open-close mold device 800, an ejection device 200 that ejects a molded product molded by the mold device 800, an injection device 300 that injects a molding material to the mold device 800, a moving device 400 that advances and retreats the injection device 300 with respect to the mold device 800, a control device 700 that controls each component of the injection molding machine 10, and a frame 900 that supports each component of the injection molding machine 10. The frame 900 includes a clamp device frame 910 that supports the clamp device 100 and an injection device frame 920 that supports the injection device 300. The clamp device frame 910 and the injection device frame 920 are each provided to the floor 2 via horizontal adjustment casters 930. The control device 700 is arranged in an inner space of the injection device frame 920. Hereinafter, each component of the injection molding machine 10 will be described.

[0023] (Clamp device)

[0024] In the description of the clamp device 100, the moving direction of the movable platen 120 at the time of closing the mold (for example, the positive direction of the X axis) is set as the front, and the moving direction of the movable platen 120 at the time of opening the mold (for example, the negative direction of the X axis) is set as the back.

[0025] The clamp device 100 performs closing of the mold, pressure increase, clamping, pressure decrease, and opening of the mold of the mold device 800. The mold device 800 includes a fixed mold 810 and a movable mold 820.

[0026] The clamp device 100 is, for example, a horizontal type, and the mold opening and closing direction is the horizontal direction. The clamp device 100 has a fixed platen 110 that mounts the fixed mold 810, a movable platen 120 that mounts the movable mold 820, and a moving mechanism 102 that moves the movable platen 120 with respect to the fixed platen 110 in the mold opening and closing direction.

[0027] The fixed platen 110 is fixed with respect to the clamp device frame 910. The fixed mold 810 is mounted on the surface of the fixed platen 110 that opposes the movable platen 120.

[0028] The movable platen 120 is arranged to be movable with respect to the clamp device frame 910 in the mold opening and closing direction. A guide 101 that guides the movable platen 120 is laid on the clamp device frame 910. The movable mold 820 is mounted on the surface of the movable platen 120 that opposes the fixed platen 110.

[0029] The moving mechanism 102 performs mold closing, pressure buildup, mold clamping, pressure release, and mold opening of the mold device 800 by advancing and retracting the movable platen 120 with respect to the fixed platen 110. The moving mechanism 102 has a toggle base 130 disposed apart from the fixed platen 110, a connecting rod 140 linking the fixed platen 110 and the toggle base 130, a toggle mechanism 150 that moves the movable platen 120 with respect to the toggle base 130 in the mold opening and closing direction, a mold clamping motor 160 that operates the toggle mechanism 150, a motion conversion mechanism 170 that converts the rotational motion of the mold clamping motor 160 into linear motion, and a mold thickness adjustment mechanism 180 that adjusts the interval between the fixed platen 110 and the toggle base 130.

[0030] The toggle base 130 is disposed apart from the fixed platen 110 and is placed on the mold clamping device frame 910 so as to be movable in the mold opening and closing direction. Alternatively, the toggle base 130 can be disposed so as to be movable along a guide provided on the mold clamping device frame 910. The guide of the toggle base 130 can be common with the guide 101 of the movable platen 120.

[0031] In the present embodiment, the fixed platen 110 is fixed with respect to the mold clamping device frame 910 and the toggle base 130 is disposed so as to be movable in the mold opening and closing direction with respect to the mold clamping device frame 910, but the present application is not limited thereto. The toggle base 130 can be fixed with respect to the mold clamping device frame 910 and the fixed platen 110 can be disposed so as to be movable in the mold opening and closing direction with respect to the mold clamping device frame 910.

[0032] The connecting rod 140 links the fixed platen 110 and the toggle base 130 apart by an interval L in the mold opening and closing direction. A plurality of (for example, four) connecting rods 140 can be used. The plurality of connecting rods 140 are disposed so as to be parallel to the mold opening and closing direction and extend in accordance with the mold clamping force. A connecting rod strain detector 141 that detects the strain of the connecting rod 140 can be provided on at least one of the connecting rods 140. The connecting rod strain detector 141 transmits a signal indicating the detection result thereof to the control device 700. The detection result of the connecting rod strain detector 141 is used for detection of the mold clamping force and the like.

[0033] In the present embodiment, the connecting rod strain detector 141 is used as the mold clamping force detector that detects the mold clamping force, but the present application is not limited thereto. The mold clamping force detector is not limited to the strain gauge type and can be a piezoelectric type, a capacitance type, a hydraulic type, an electromagnetic type, or the like, and the installation position thereof is not limited to the connecting rod 140.

[0034] The toggle mechanism 150 is provided between the movable platen 120 and the toggle base 130, and moves the movable platen 120 with respect to the toggle base 130 in the mold opening and closing direction. The toggle mechanism 150 has a cross head 151 that moves in the mold opening and closing direction, and a pair of link mechanisms that are bent and stretched by the movement of the cross head 151. The pair of link mechanisms each have a first link 152 and a second link 153 that are connected by a pin or the like so as to be freely bent and stretched. The first link 152 is installed so as to be freely swingable with respect to the movable platen 120 by a pin or the like. The second link 153 is installed so as to be freely swingable with respect to the toggle base 130 by a pin or the like. The second link 153 is installed to the cross head 151 via a third link 154. If the cross head 151 is advanced and retracted with respect to the toggle base 130, the first link 152 and the second link 153 are bent and stretched, and thus the movable platen 120 is advanced and retracted with respect to the toggle base 130.

[0035] In addition, the structure of the toggle mechanism 150 is not limited to the structure shown in Figure 1 and Figure 2 For example, in Figure 1 and Figure 2 , the number of nodes of each link mechanism is five, but can be four, and one end of the third link 154 can be joined to the nodes of the first link 152 and the second link 153.

[0036] The clamp motor 160 is installed to the toggle base 130, and operates the toggle mechanism 150. The clamp motor 160 bends and stretches the first link 152 and the second link 153 by advancing and retracting the cross head 151 with respect to the toggle base 130, and thus advances and retracts the movable platen 120 with respect to the toggle base 130. The clamp motor 160 is directly connected to the motion conversion mechanism 170, but can be connected to the motion conversion mechanism 170 via a belt or a pulley or the like.

[0037] The motion conversion mechanism 170 converts the rotational motion of the clamp motor 160 to the linear motion of the cross head 151. The motion conversion mechanism 170 includes a lead screw shaft and a lead screw nut that is screwed to the lead screw shaft. A ball or a roller can be interposed between the lead screw shaft and the lead screw nut.

[0038] The clamp device 100 performs a mold closing process, a pressure increasing process, a mold clamping process, a pressure releasing process, a mold opening process, and the like under the control of the control device 700.

[0039] In the mold closing process, the cross head 151 is advanced to a mold closing end position at a set movement speed by driving the clamp motor 160, and the movable platen 120 is advanced so that the movable mold 820 comes into contact with the fixed mold 810. For example, the position or the movement speed of the cross head 151 is detected using a clamp motor encoder 161 or the like. The clamp motor encoder 161 detects the rotation of the clamp motor 160, and transmits a signal indicating the detection result to the control device 700.

[0040] In addition, the cross head position detector that detects the position of the cross head 151 and the cross head moving speed detector that detects the moving speed of the cross head 151 are not limited to the clamp motor encoder 161, and a general detector can be used. Also, the movable platen position detector that detects the position of the movable platen 120 and the movable platen moving speed detector that detects the moving speed of the movable platen 120 are not limited to the clamp motor encoder 161, and a general detector can be used.

[0041] In the pressure buildup process, the cross head 151 is further advanced from the clamp end position to the clamp position by further driving the clamp motor 160, and thus the clamp force is generated.

[0042] In the clamp process, the position of the cross head 151 is maintained at the clamp position by driving the clamp motor 160. In the clamp process, the clamp force generated in the pressure buildup process is maintained. In the clamp process, the cavity space 801 (refer to FIG. 1) is formed between the movable mold 820 and the fixed mold 810. The injection device 300 fills the cavity space 801 with a liquid molding material. By curing the filled molding material, a molded product can be obtained. Figure 2

[0043] The number of the cavity spaces 801 can be one or a plurality. In the latter case, a plurality of molded products can be obtained at the same time. An insert can be arranged in a part of the cavity space 801, and a molding material can be filled in another part of the cavity space 801. A molded product in which the insert and the molding material are integrated can be obtained.

[0044] In the pressure relief process, the cross head 151 is retreated from the clamp position to the clamp start position by driving the clamp motor 160, and the movable platen 120 is retreated to reduce the clamp force. The clamp start position and the clamp end position can be the same position.

[0045] In the mold opening process, the cross head 151 is retreated from the mold opening start position to the mold opening end position at a set moving speed by driving the clamp motor 160, and the movable platen 120 is retreated to separate the movable mold 820 from the fixed mold 810. Then, the ejection device 200 ejects the molded product from the movable mold 820.

[0046] ​The conditions set in the closing process, the pressure increasing process, and the clamping process are set uniformly as a series of set conditions. For example, the moving speed or position of the cross head 151 (including the closing start position, the moving speed switching position, the closing end position, and the clamping position) in the closing process and the pressure increasing process and the clamping force are set uniformly as a series of set conditions. The closing start position, the moving speed switching position, the closing end position, and the clamping position are arranged in order from the rear side to the front side, indicating the start or end point of the interval in which the moving speed is set. The moving speed is set for each interval. The moving speed switching position can be one or a plurality of positions. The moving speed switching position can not be set. Only one of the clamping position and the clamping force can be set.

[0047] The conditions set in the decompression process and the opening process are also set in the same manner. For example, the moving speed or position of the cross head 151 (the opening start position, the moving speed switching position, and the opening end position) in the decompression process and the opening process are set uniformly as a series of set conditions. The opening start position, the moving speed switching position, and the opening end position are arranged in order from the front side to the rear side, indicating the start or end point of the interval in which the moving speed is set. The moving speed is set for each interval. The moving speed switching position can be one or a plurality of positions. The moving speed switching position can not be set. The opening start position and the closing end position can be the same position. Also, the opening end position and the closing start position can be the same position.

[0048] In addition, instead of the moving speed or position of the cross head 151 or the like, the moving speed or position of the movable platen 120 or the like can be set. Also, instead of the position of the cross head (for example, the clamping position) or the position of the movable platen, the clamping force can be set.

[0049] However, the toggle mechanism 150 amplifies the driving force of the clamping motor 160 and transmits it to the movable platen 120. The amplification ratio thereof is also referred to as the toggle ratio. The toggle ratio changes according to the angle θ (hereinafter, also referred to as "link angle θ") formed by the first link 152 and the second link 153. The link angle θ is found from the position of the cross head 151. When the link angle θ is 180°, the toggle ratio becomes the maximum.

[0050] When the thickness of the mold device 800 has changed due to replacement of the mold device 800 or temperature change of the mold device 800 or the like, mold thickness adjustment is performed to obtain a predetermined clamping force at the time of clamping. In the mold thickness adjustment, for example, the interval L between the fixed platen 110 and the toggle seat 130 is adjusted so that the link angle θ of the toggle mechanism 150 becomes a predetermined angle at the time of mold contact at which the movable mold 820 and the fixed mold 810 come into contact with each other.

[0051] The mold clamping device 100 has a mold thickness adjusting mechanism 180. The mold thickness adjusting mechanism 180 adjusts the interval L between the fixed platen 110 and the toggle base 130, thereby performing mold thickness adjustment. In addition, the timing of the mold thickness adjustment is, for example, during a period from the end of a molding cycle to the start of the next molding cycle. The mold thickness adjusting mechanism 180 has, for example, a screw shaft 181 formed at the rear end portion of the connecting rod 140, a screw nut 182 held so as to be rotatable and non-retractable with respect to the toggle base 130, and a mold thickness adjusting motor 183 that rotates the screw nut 182 screwed with the screw shaft 181.

[0052] The screw shaft 181 and the screw nut 182 are provided for each connecting rod 140. The rotational drive force of the mold thickness adjusting motor 183 can be transmitted to the plurality of screw nuts 182 via a rotational drive force transmission portion 185. The plurality of screw nuts 182 can be rotated synchronously. In addition, by changing the transmission path of the rotational drive force transmission portion 185, the plurality of screw nuts 182 can also be rotated individually.

[0053] The rotational drive force transmission portion 185 is constituted by, for example, a gear. At this time, a driven gear is formed at the outer periphery of each screw nut 182, a drive gear is attached to the output shaft of the mold thickness adjusting motor 183, and an intermediate gear that engages with the plurality of driven gears and the drive gear is held so as to be rotatable at the central portion of the toggle base 130. In addition, the rotational drive force transmission portion 185 can also be constituted by a belt or a pulley instead of a gear.

[0054] The operation of the mold thickness adjusting mechanism 180 is controlled by a control device 700. The control device 700 rotates the screw nut 182 by driving the mold thickness adjusting motor 183. As a result, the position of the toggle base 130 with respect to the connecting rod 140 is adjusted, and the interval L between the fixed platen 110 and the toggle base 130 is adjusted. In addition, a plurality of mold thickness adjusting mechanisms can also be used in combination.

[0055] The interval L is detected using a mold thickness adjusting motor encoder 184. The mold thickness adjusting motor encoder 184 detects the amount of rotation or the direction of rotation of the mold thickness adjusting motor 183, and transmits a signal indicating the detection result to the control device 700. The detection result of the mold thickness adjusting motor encoder 184 is used for monitoring or control of the position of the toggle base 130 or the interval L. In addition, the toggle base position detector that detects the position of the toggle base 130 and the interval detector that detects the interval L are not limited to the mold thickness adjusting motor encoder 184, and a general detector can be used.

[0056] The mold clamping device 100 can have a mold temperature adjuster that adjusts the temperature of the mold device 800. The mold device 800 has a flow path of a temperature adjustment medium inside thereof. The mold temperature adjuster adjusts the temperature of the temperature adjustment medium supplied to the flow path of the mold device 800, thereby adjusting the temperature of the mold device 800.

[0057] In addition, the mold clamping device 100 of the present embodiment is a horizontal type in which the mold opening and closing direction is the horizontal direction, but can be a vertical type in which the mold opening and closing direction is the vertical direction.

[0058] In addition, the mold clamping device 100 of the present embodiment has the mold clamping motor 160 as a drive source, but can have a hydraulic cylinder instead of the mold clamping motor 160. Furthermore, the mold clamping device 100 can have a linear motor for mold opening and closing, and can have an electromagnetic body for mold clamping.

[0059] (Ejection device)

[0060] In the description of the ejection device 200, as with the description of the mold clamping device 100, the moving direction of the movable platen 120 at the time of mold closing (for example, the positive direction of the X axis) is taken as the front, and the moving direction of the movable platen 120 at the time of mold opening (for example, the negative direction of the X axis) is taken as the back.

[0061] The ejection device 200 is attached to the movable platen 120 and advances and retreats together with the movable platen 120. The ejection device 200 has an ejection rod 210 that ejects a molded product from the mold device 800 and a drive mechanism 220 that moves the ejection rod 210 in the moving direction of the movable platen 120 (the X axis direction).

[0062] The ejection rod 210 is disposed so as to be able to advance and retreat in the through hole of the movable platen 120. The front end portion of the ejection rod 210 is in contact with an ejection plate 826 of the movable mold 820. The front end portion of the ejection rod 210 can be joined to the ejection plate 826, or can not be joined thereto.

[0063] The drive mechanism 220 has, for example, an ejection motor and a motion conversion mechanism that converts the rotational motion of the ejection motor into the linear motion of the ejection rod 210. The motion conversion mechanism includes a screw shaft and a screw nut that is screwed with the screw shaft. A ball or a roller can be interposed between the screw shaft and the screw nut.

[0064] The ejection device 200 performs an ejection process under the control of the control device 700. In the ejection process, the ejection plate 826 is advanced by causing the ejection rod 210 to advance from the standby position to the ejection position at a set moving speed, so as to eject the molded product. Then, the ejection rod 210 is caused to retreat at the set moving speed by driving the ejection motor, and the ejection plate 826 is caused to retreat to the original standby position.

[0065] For example, the position or the moving speed of the ejector rod 210 is detected using an ejector motor encoder. The ejector motor encoder detects the rotation of the ejector motor and sends a signal indicating the detection result to the control device 700. In addition, the ejector rod position detector that detects the position of the ejector rod 210 and the ejector rod moving speed detector that detects the moving speed of the ejector rod 210 are not limited to the ejector motor encoder, and a general detector can be used.

[0066] (injection device)

[0067] In the description of the injection device 300, unlike the description of the clamping device 100 and the description of the ejector device 200, the moving direction of the screw 330 at the time of filling (for example, the negative direction of the X axis) is set as the front direction, and the moving direction of the screw 330 at the time of metering (for example, the positive direction of the X axis) is set as the rear direction.

[0068] The injection device 300 is provided on a sliding base 301 configured to be able to advance and retreat with respect to an injection device frame 920. The injection device 300 is configured to be able to advance and retreat with respect to the mold device 800. The injection device 300 is in contact with the mold device 800 and fills the cavity space 801 in the mold device 800 with a molding material. The injection device 300 has, for example, a cylinder 310 that heats the molding material, a nozzle 320 provided at the front end portion of the cylinder 310, a screw 330 configured to be able to advance and retreat and rotate in the cylinder 310, a metering motor 340 that rotates the screw 330, an injection motor 350 that advances and retreats the screw 330, and a load detector 360 that detects the load transmitted between the injection motor 350 and the screw 330.

[0069] The cylinder 310 heats the molding material supplied to the inside from a supply port 311. The molding material includes, for example, resin and the like. The molding material is formed, for example, in a granular shape and is supplied to the supply port 311 in a solid state. The supply port 311 is formed at the rear portion of the cylinder 310. A cooler 312 such as a water-cooled cylinder is provided at the outer periphery of the rear portion of the cylinder 310. A first heater 313 such as a belt heater and a first temperature detector 314 are provided at the outer periphery of the cylinder 310 further forward than the cooler 312.

[0070] The cylinder 310 is divided into a plurality of regions in the axial direction (for example, the X axis direction) of the cylinder 310. The first heater 313 and the first temperature detector 314 are provided at the respective regions. The control device 700 controls the first heater 313 so that the detection temperature of the first temperature detector 314 becomes a set temperature, which is set for each region.

[0071] The nozzle 320 is provided at the front end portion of the cylinder 310, and is pressed against the mold device 800. A second heater 323 and a second temperature detector 324 are provided on the outer periphery of the nozzle 320. The control device 700 controls the second heater 323 so that the detected temperature of the nozzle 320 becomes a set temperature.

[0072] The screw 330 is configured to be rotatable and retractable / extendable within the cylinder 310. If the screw 330 is rotated, the molding material is transported to the front along the helical groove of the screw 330. The molding material is gradually melted by the heat from the cylinder 310 while being transported to the front. As the liquid molding material is transported to the front of the screw 330 and accumulated in the front portion of the cylinder 310, the screw 330 is retracted. Then, if the screw 330 is extended, the liquid molding material accumulated in the front of the screw 330 is injected from the nozzle 320, and filled in the mold device 800.

[0073] A check ring 331 is installed at the front portion of the screw 330 so as to be retractable / extendable, and this check ring 331 functions as a check valve to prevent the backflow of the molding material from the front to the rear of the screw 330 when the screw 330 is pushed forward.

[0074] When the screw 330 is extended, the check ring 331 is pushed to the rear by the pressure of the molding material in the front of the screw 330, so as to be relatively retracted to a closed position (see FIG. 2) that closes the flow path of the molding material with respect to the screw 330. Thus, the backflow of the molding material accumulated in the front of the screw 330 to the rear is prevented. Figure 2

[0075] On the other hand, when the screw 330 is rotated, the check ring 331 is pushed to the front by the pressure of the molding material transported to the front along the helical groove of the screw 330, so as to be relatively extended to an open position (see FIG. 1) that opens the flow path of the molding material with respect to the screw 330. Thus, the molding material is transported to the front of the screw 330. Figure 1

[0076] The check ring 331 can be either one of a co-rotating type that rotates together with the screw 330 and a non-co-rotating type that does not rotate together with the screw 330.

[0077] In addition, the injection device 300 can have a drive source that retracts / extends the check ring 331 with respect to the screw 330 between the open position and the closed position.

[0078] The metering motor 340 rotates the screw 330. The drive source that rotates the screw 330 is not limited to the metering motor 340, and can be, for example, a hydraulic pump or the like.

[0079] ​​The injection motor 350 advances and retreats the screw 330. A motion conversion mechanism or the like that converts the rotational motion of the injection motor 350 to the linear motion of the screw 330 is provided between the injection motor 350 and the screw 330. The motion conversion mechanism has, for example, a lead screw shaft and a lead screw nut that is screwed with the lead screw shaft. A ball or a roller or the like can be provided between the lead screw shaft and the lead screw nut. The driving source that advances and retreats the screw 330 is not limited to the injection motor 350, and can be, for example, a hydraulic cylinder or the like.

[0080] The load detector 360 detects the load transmitted between the injection motor 350 and the screw 330. The detected load is converted into pressure by the control device 700. The load detector 360 is provided on the load transmission path between the injection motor 350 and the screw 330, and detects the load acting on the load detector 360.

[0081] The load detector 360 transmits a signal of the detected load to the control device 700. The load detected by the load detector 360 is converted into pressure acting between the screw 330 and the molding material, and is used for controlling or monitoring the pressure that the screw 330 receives from the molding material, the back pressure to the screw 330, and the pressure acting from the screw 330 to the molding material, or the like.

[0082] In addition, the pressure detector that detects the pressure of the molding material is not limited to the load detector 360, and a general detector can be used. For example, a nozzle pressure sensor or a mold internal pressure sensor can be used. The nozzle pressure sensor is provided to the nozzle 320. The mold internal pressure sensor is provided inside the mold device 800.

[0083] The injection device 300 performs a metering process, a filling process, and a holding process, or the like, under the control of the control device 700. The filling process and the holding process can be collectively referred to as an injection process.

[0084] In the metering process, the screw 330 is rotated at a set rotational speed by driving the metering motor 340, to transport the molding material to the front along the helical groove of the screw 330. By this, the molding material is gradually melted. As the liquid molding material is transported to the front of the screw 330 and accumulated in the front portion of the cylinder 310, the screw 330 is retreated. For example, the rotational speed of the screw 330 is detected using the metering motor encoder 341. The metering motor encoder 341 detects the rotation of the metering motor 340, and transmits a signal indicating the detection result to the control device 700. In addition, the rotational speed detector of the screw 330 is not limited to the metering motor encoder 341, and a general detector can be used.

[0085] In the metering process, in order to limit the screw 330 from sharply retreating, the injection motor 350 can be driven to apply a set back pressure to the screw 330. For example, the back pressure to the screw 330 is detected using the load detector 360. If the screw 330 retreats to the metering end position and the prescribed amount of molding material is accumulated in front of the screw 330, the metering process is ended.

[0086] The position and rotational speed of the screw 330 in the metering process are set as a series of set conditions. For example, the metering start position, the rotational speed switching position, and the metering end position are set. These positions are arranged in order from the front side to the rear side, indicating the start or end point of the interval of the set rotational speed. The rotational speed is set for each interval. The rotational speed switching position can be one or a plurality of positions. The rotational speed switching position can not be set. Further, the back pressure is set for each interval.

[0087] In the filling process, the injection motor 350 is driven to advance the screw 330 at a set moving speed, and the liquid molding material accumulated in front of the screw 330 is filled into the cavity space 801 in the mold device 800. For example, the position or moving speed of the screw 330 is detected using the injection motor encoder 351. The injection motor encoder 351 detects the rotation of the injection motor 350 and transmits a signal indicating the detection result to the control device 700. If the position of the screw 330 reaches a set position, switching from the filling process to the holding process (so-called V / P switching) is performed. The position at which the V / P switching is performed is also referred to as the V / P switching position. The set moving speed of the screw 330 can be changed according to the position of the screw 330, time, or the like.

[0088] The position and moving speed of the screw 330 in the filling process are set as a series of set conditions. For example, the filling start position (also referred to as the "injection start position"), the moving speed switching position, and the V / P switching position are set. These positions are arranged in order from the rear side to the front side, indicating the start or end point of the interval of the set moving speed. The moving speed is set for each interval. The moving speed switching position can be one or a plurality of positions. The moving speed switching position can not be set.

[0089] The upper limit value of the pressure of the screw 330 is set for each interval of the set moving speed of the screw 330. The pressure of the screw 330 is detected by the load detector 360. When the pressure of the screw 330 is below the set pressure, the screw 330 advances at the set moving speed. On the other hand, when the pressure of the screw 330 exceeds the set pressure, the screw 330 advances at a moving speed slower than the set moving speed in order to protect the mold, so that the pressure of the screw 330 becomes below the set pressure.

[0090] Further, in the filling step, after the position of the screw 330 reaches the V / P switching position, the screw 330 can be stopped at the V / P switching position, and then the V / P switching can be performed. Instead of stopping the screw 330, a slow forward movement or a slow backward movement of the screw 330 can be performed before the V / P switching is to be performed. Further, the screw position detector that detects the position of the screw 330 and the screw movement speed detector that detects the movement speed of the screw 330 are not limited to the injection motor encoder 351, and a general detector can be used.

[0091] In the holding step, the injection motor 350 is driven to push the screw 330 forward, and the pressure of the molding material at the front end of the screw 330 (hereinafter, also referred to as "holding pressure") is maintained at a set pressure, and the molding material remaining in the cylinder 310 is pushed toward the mold device 800. The molding material that has been insufficient in the mold device 800 due to cooling shrinkage can be supplemented. For example, the holding pressure is detected using the load detector 360. The set value of the holding pressure can be changed according to the elapsed time from the start of the holding step, or the like. The holding pressure in the holding step and the holding time for maintaining the holding pressure can each be set to a plurality of values, or can be uniformly set as a series of set conditions.

[0092] In the holding step, the molding material in the cavity space 801 in the mold device 800 is gradually cooled, and at the end of the holding step, the inlet of the cavity space 801 is closed by the solidified molding material. This state is referred to as gate sealing, and prevents the molding material from flowing backward from the cavity space 801. After the holding step, the cooling step is started. In the cooling step, the solidification of the molding material in the cavity space 801 is performed. To shorten the molding cycle time, the metering step can be performed in the cooling step.

[0093] Further, the injection device 300 of the present embodiment is of the coaxial screw type, but can be of the screw pre-plasticizing type or the like. The injection device of the screw pre-plasticizing type supplies the molding material melted in a plasticizing cylinder to an injection cylinder, and injects the molding material from the injection cylinder into a mold device. In the plasticizing cylinder, the screw is configured to be rotatable and non-retractable, or the screw is configured to be rotatable and retractable. On the other hand, in the injection cylinder, the plunger is configured to be retractable and non-rotatable.

[0094] Further, the injection device 300 of the present embodiment is of the horizontal type in which the axial direction of the cylinder 310 is the horizontal direction, but can be of the vertical type in which the axial direction of the cylinder 310 is the vertical direction. The mold clamping device combined with the injection device 300 of the vertical type can be of the vertical type or of the horizontal type. Similarly, the mold clamping device combined with the injection device 300 of the horizontal type can be of the horizontal type or of the vertical type.

[0095] (Mobile device)

[0096] In the description of the moving device 400, as with the description of the injection device 300, the moving direction of the screw 330 at the time of filling (for example, the negative direction of the X axis) is set as the front direction, and the moving direction of the screw 330 at the time of metering (for example, the positive direction of the X axis) is set as the rear direction.

[0097] The moving device 400 advances and retreats the injection device 300 with respect to the mold device 800. Also, the moving device 400 presses the nozzle 320 with respect to the mold device 800 to generate the nozzle contact pressure. The moving device 400 includes a hydraulic pump 410, a motor 420 as a drive source, a hydraulic cylinder 430 as a hydraulic actuator, and the like.

[0098] The hydraulic pump 410 has a first port 411 and a second port 412. The hydraulic pump 410 is a pump that can rotate in both directions, and by switching the rotating direction of the motor 420, working fluid (for example, oil) is sucked from either one of the first port 411 and the second port 412 and is discharged from the other port to generate hydraulic pressure. In addition, the hydraulic pump 410 can also suck working fluid from a tank and discharge the working fluid from either one of the first port 411 and the second port 412.

[0099] The motor 420 operates the hydraulic pump 410. The motor 420 drives the hydraulic pump 410 by the rotating direction and the rotating torque corresponding to the control signal from the control device 700. The motor 420 can be an electric motor, or can be an electric servo motor.

[0100] The hydraulic cylinder 430 has a cylinder main body 431, a piston 432, and a piston rod 433. The cylinder main body 431 is fixed with respect to the injection device 300. The piston 432 divides the inside of the cylinder main body 431 into a front chamber 435 as a first chamber and a rear chamber 436 as a second chamber. The piston rod 433 is fixed with respect to the fixed platen 110.

[0101] The front chamber 435 of the hydraulic cylinder 430 is connected to the first port 411 of the hydraulic pump 410 via a first flow path 401. The working fluid discharged from the first port 411 is supplied to the front chamber 435 via the first flow path 401, whereby the injection device 300 is pushed in the front direction. The injection device 300 advances and the nozzle 320 is pressed against the fixed mold 810. The front chamber 435 functions as a pressure chamber that generates the nozzle contact pressure of the nozzle 320 by the pressure of the working fluid supplied from the hydraulic pump 410.

[0102] On the other hand, the rear chamber 436 of the hydraulic cylinder 430 is connected to the second port 412 of the hydraulic pump 410 via the second flow path 402. The working fluid discharged from the second port 412 is supplied to the rear chamber 436 of the hydraulic cylinder 430 via the second flow path 402, whereby the injection device 300 is pushed rearward. The injection device 300 retreats, and thus the nozzle 320 is separated from the stationary mold 810.

[0103] In addition, in the present embodiment, the moving device 400 includes the hydraulic cylinder 430, but the present application is not limited thereto. For example, an electric motor and a motion conversion mechanism that converts the rotational motion of the electric motor into the linear motion of the injection device 300 can be used instead of the hydraulic cylinder 430.

[0104] (CONTROL DEVICE)

[0105] The control device 700 is constituted by, for example, a computer, and has a CPU (Central Processing Unit) 701, a storage medium 702 such as a memory, an input interface 703, and an output interface 704, as shown in FIG. 7. The control device 700 performs various controls by causing the CPU 701 to execute a program stored in the storage medium 702. Also, the control device 700 receives a signal from the outside through the input interface 703 and transmits a signal to the outside through the output interface 704. Figures 1-2

[0106] The control device 700 repeatedly manufactures a molded product by repeatedly performing the metering process, the mold closing process, the pressure increasing process, the mold clamping process, the filling process, the pressure maintaining process, the cooling process, the pressure releasing process, the mold opening process, and the ejection process. The series of actions for obtaining a molded product, for example, from the start of the metering process until the start of the next metering process, is also referred to as "shot" or "molding cycle". Also, the time required for one shot is also referred to as "molding cycle time" or "cycle time".

[0107] One molding cycle, for example, successively has the metering process, the mold closing process, the pressure increasing process, the mold clamping process, the filling process, the pressure maintaining process, the cooling process, the pressure releasing process, the mold opening process, and the ejection process. The order here is the order in which each process is started. The filling process, the pressure maintaining process, and the cooling process are performed during the mold clamping process. The start of the mold clamping process can coincide with the start of the filling process. The end of the pressure releasing process coincides with the start of the mold opening process.

[0108] ​In addition, in order to shorten the molding cycle time, a plurality of processes can be performed simultaneously. For example, the metering process can be performed during the cooling process of the previous molding cycle, or during the clamping process. In this case, the closing process can be performed at the beginning of the molding cycle. Also, the filling process can be started during the closing process. Also, the ejection process can be started during the opening process. When an opening and closing valve that opens and closes the flow path of the nozzle 320 is provided, the opening process can be started during the metering process. Since the molding material does not leak from the nozzle 320 even if the opening process is started during the metering process, as long as the opening and closing valve closes the flow path of the nozzle 320.

[0109] In addition, the one molding cycle can include a process other than the metering process, the closing process, the pressure increasing process, the clamping process, the filling process, the pressure maintaining process, the cooling process, the pressure decreasing process, the opening process, and the ejection process.

[0110] For example, a pre-metering back suction process in which the screw 330 is retracted to a pre-set metering start position can be performed after the pressure maintaining process is completed and before the metering process is started. The pressure of the molding material accumulated in front of the screw 330 can be reduced before the metering process is started, so that the screw 330 can be prevented from being sharply retracted at the start of the metering process.

[0111] Also, a post-metering back suction process in which the screw 330 is retracted to a pre-set filling start position (also referred to as an "injection start position") can be performed after the metering process is completed and before the filling process is started. The pressure of the molding material accumulated in front of the screw 330 can be reduced before the filling process is started, so that the molding material can be prevented from leaking from the nozzle 320 before the filling process is started.

[0112] The control device 700 is connected to an operation device 750 that accepts an input operation of a user and a display device 760 that displays a screen. The operation device 750 and the display device 760 are constituted by, for example, a touch panel 770, and can be integrated. The touch panel 770 as the display device 760 displays a screen under the control of the control device 700. Information such as a setting of the injection molding machine 10, a current state of the injection molding machine 10, and the like can be displayed on the screen of the touch panel 770. Also, an operation section such as a button, an input field, and the like for accepting an input operation of a user can be displayed on the screen of the touch panel 770. The touch panel 770 as the operation device 750 detects an input operation of a user on the screen and outputs a signal corresponding to the input operation to the control device 700. Thus, for example, a user can confirm information displayed on the screen while operating the operation section provided on the screen, and perform a setting (including input of a setting value) of the injection molding machine 10 and the like. Also, by operating the operation section provided on the screen, a user can perform an operation of the injection molding machine 10 corresponding to the operation section. Note that the operation of the injection molding machine 10 can be, for example, an operation (including stop) of the clamping device 100, the ejection device 200, the injection device 300, the moving device 400, and the like. Also, the operation of the injection molding machine 10 can be, for example, switching of a screen displayed on the touch panel 770 as the display device 760.

[0113] Note that the operation device 750 and the display device 760 according to the present embodiment are integrated into the touch panel 770, but can be provided separately. Also, a plurality of operation devices 750 can be provided. The operation device 750 and the display device 760 are disposed on the operation side (negative direction of the Y axis) of the clamping device 100 (more specifically, the fixed platen 110).

[0114] (Mold Device)

[0115] Next, reference will be made to Figure 3 A mold device 800 according to an embodiment will be described. The mold device 800 includes a fixed mold 810 and a movable mold 820. The fixed mold 810 is attached to the fixed platen 110 of the injection molding machine 10. The movable mold 820 is attached to the movable platen 120 of the injection molding machine 10. The mold device 800 forms a cavity space 801 between the fixed mold 810 and the movable mold 820 at the time of clamping. The cavity space 801 is a space in which a preheated molding material is filled in the cylinder 310 of the injection molding machine 10. An injection molding system is constituted by the mold device 800 and the injection molding machine 10.

[0116] The stationary mold 810 has, for example, a first mold portion 811, a first cooling portion 812, and a first support portion 813. The first mold portion 811 contacts the movable mold 820 at the time of mold clamping, and forms a part of a wall surface of the cavity space 801. The first mold portion 811 is heated by the heat of the molding material filled in the cavity space 801. The temperature of the first cooling portion 812 is adjusted to a temperature lower than the temperature of the first mold portion 811 at the time of filling the molding material. The first support portion 813 supports one of the first cooling portion 812 and the first mold portion 811 so as to be relatively movable with respect to the other. The first support portion 813 functions as a guide. The first cooling portion 812 and the first mold portion 811 are relatively movable in two directions, an opening direction (for example, the negative direction of the X axis) and a closing direction (for example, the positive direction of the X axis), between a position apart from each other and a position contacting each other.

[0117] The first mold portion 811 is fixed with respect to the stationary platen 110, and the first support portion 813 supports the first cooling portion 812 so as to be movable with respect to the stationary platen 110. The first cooling portion 812 is disposed in a space between the first mold portion 811 and the stationary platen 110. In addition, although not shown, the first cooling portion 812 can be fixed with respect to the stationary platen 110, and in this case, the first support portion 813 supports the first mold portion 811 so as to be movable with respect to the stationary platen 110. It is only necessary that the first cooling portion 812 and the first mold portion 811 are relatively movable in the two directions, the opening direction and the closing direction.

[0118] The first mold portion 811 and the first cooling portion 812 can each be a plate shape perpendicular with respect to the mold opening and closing direction. In order to cool the entire first mold portion 811, it is preferable that the first cooling portion 812 has the same size or more than the first mold portion 811, as viewed from the mold opening and closing direction. The first support portion 813 can be a bar shape parallel with respect to the mold opening and closing direction. The first support portion 813 is inserted into a through-hole 812a that penetrates the first cooling portion 812 in the mold opening and closing direction. A plurality of first support portions 813 can be provided. The first support portion 813 is fixed with respect to the stationary platen 110, and the first cooling portion 812 moves along the first support portion 813. The first support portion 813 is compressed in the mold opening and closing direction at the time of mold clamping, and thereby transmits the mold clamping force. A plurality of first support portions 813 can be provided so that the mold clamping force is uniformly applied to the first mold portion 811. The first support portions 813 are provided, for example, at four corners of the first mold portion 811, respectively.

[0119] As Figure 3 in (A) and Figure 3As shown in (B), the first cooling section 812 can be separated from the first mold section 811 at the time of filling the molding material. That is, the first cooling section 812 can be separated from the first mold section 811 in the filling process. A space is formed between the first cooling section 812 and the first mold section 811, and the space restricts the movement of heat. The temperature of the first mold section 811 is higher than that in the case where the first cooling section 812 is in contact with the first mold section 811, and the temperature of the wall surface of the cavity space 801 is higher. As a result, the flowability of the molding material at the time of filling is good, and the shape and size of the cavity space 801 are easily transferred to the molded product. Therefore, the mold device 800 has good transferability. In order to improve the transferability of the mold device 800, it is not necessary to heat the first mold section 811 by the heating device at the time of filling the molding material. However, the first mold section 811 can be heated by the heating device at the time of filling the molding material. Regardless, the temperature of the first mold section 811 is higher than that in the case where the first cooling section 812 is in contact with the first mold section 811, and the temperature of the wall surface of the cavity space 801 is higher.

[0120] It is preferable that the first cooling section 812 be separated from the first mold section 811 at least from the start to the end of the filling process. Further, it is more preferable that the first cooling section 812 be separated from the first mold section 811 at least a part of (preferably, the entire) pressure maintaining process after the filling process. In the pressure maintaining process, if the temperature of the first mold section 811 is high, it is easy to supplement the molding material that is insufficient in the cavity space 801 due to shrinkage by cooling.

[0121] As shown in (A), the first cooling section 812 can be separated from the first mold section 811 at the time of filling the molding material. That is, the first cooling section 812 can be separated from the first mold section 811 in the filling process. A space is formed between the first cooling section 812 and the first mold section 811, and the space restricts the movement of heat. The temperature of the first mold section 811 is higher than that in the case where the first cooling section 812 is in contact with the first mold section 811, and the temperature of the wall surface of the cavity space 801 is higher. As a result, the flowability of the molding material at the time of filling is good, and the shape and size of the cavity space 801 are easily transferred to the molded product. Therefore, the mold device 800 has good transferability. In order to improve the transferability of the mold device 800, it is not necessary to heat the first mold section 811 by the heating device at the time of filling the molding material. However, the first mold section 811 can be heated by the heating device at the time of filling the molding material. Regardless, the temperature of the first mold section 811 is higher than that in the case where the first cooling section 812 is in contact with the first mold section 811, and the temperature of the wall surface of the cavity space 801 is higher. Figure 3 As shown in (C), the first cooling section 812 can be in contact with the first mold section 811 at the time of cooling the molding material. That is, the first cooling section 812 can be in contact with the first mold section 811 in the cooling process. The first cooling section 812 takes heat from the first mold section 811 by being in contact with the first mold section 811. The first mold section 811 can be cooled, and thus the cooling time in which the molding material is solidified to the extent that the molded product can be taken out of the mold device 800 can be shortened. The effect of shortening the cooling time can be significantly obtained particularly in the case where the molded product is a thick-walled product such as a lens.

[0122] For example, the first cooling section 812 and the first mold section 811 are relatively moved from a position where they are separated from each other to a position where they are in contact with each other at the time of switching from the pressure maintaining process to the cooling process. In addition, the first cooling section 812 can be in contact with the first mold section 811 from the middle of the cooling process. Even if the first cooling section 812 is in contact with the first mold section 811 from the middle of the cooling process, the cooling time can be shortened.

[0123] However, many molded articles have a dimension in a direction orthogonal to the direction of clamping that is larger than a dimension in a direction along the direction of clamping. For example, a lens, a connector, a lid of a container, and the like have a dimension in a direction orthogonal to the direction of clamping that is larger than a dimension in a direction along the direction of clamping. This is because the cavity space 801 is formed in a parting surface (a parting surface of the fixed mold 810 and the movable mold 820) of the mold device 800. That is, the cavity space 801 expands in a direction orthogonal to the direction of clamping.

[0124] As described above, many molded articles have a dimension in a direction orthogonal to the direction of clamping that is larger than a dimension in a direction along the direction of clamping. Therefore, in order to improve the dimensional accuracy of the molded article, it is important to suppress uneven cooling of the mold device 800 in a direction orthogonal to the direction of clamping. This is because uneven shrinkage of the molded article can be reduced, and deformation of the molded article can be reduced. That is, the shape and the size of the cavity space 801 of the mold device 800 can be transferred to the molded article with high accuracy.

[0125] In the present embodiment, the first mold portion 811 and the first cooling portion 812 are relatively moved in the mold opening and closing direction. Compared to a case in which the first cooling portion 812 is moved in a direction orthogonal to the mold opening and closing direction as in Patent Literature 1, uneven cooling of the first mold portion 811 in a direction orthogonal to the mold opening and closing direction (that is, the direction of clamping) can be suppressed. As a result, uneven shrinkage of the molded article can be reduced, and deformation of the molded article can be reduced, and thus the transfer accuracy from the first mold portion 811 to the molded article can be improved.

[0126] The first cooling portion 812 has a flow path 812b inside for flowing a refrigerant. The temperature of the refrigerant is previously adjusted to a set temperature by a temperature adjuster not shown. The temperature adjuster and the mold device 800 are connected by a delivery pipe and a return pipe. The refrigerant is supplied to the flow path 812b via the delivery pipe. The refrigerant, after flowing through the flow path 812b, is returned to the temperature adjuster via the return pipe. The set temperature of the temperature adjuster is set to be lower than the temperature of the first mold portion 811 at the time of filling the molding material. The refrigerant is, for example, water or oil.

[0127] In order to suppress uneven cooling of the first mold portion 811 in a direction orthogonal to the direction of clamping, it is preferable that the flow path 812b be disposed so as to surround a central portion of the first mold portion 811 as viewed from the direction of clamping. A part of the sprue 802 is formed to penetrate through the central portion of the first mold portion 811. The sprue 802 is a flow path for flowing the molding material from the nozzle 320 of the injection molding machine 10 to the parting surface of the mold device 800.

[0128] In order to suppress uneven cooling of the first mold part 811 in a direction orthogonal to the mold clamping direction, the flow path 812b is preferably arranged so as to pass through the center of the first mold part 811 in the Z-axis direction as viewed from the mold clamping direction. Also, in order to suppress uneven cooling of the first mold part 811 in a direction orthogonal to the mold clamping direction, the flow path 812b is preferably arranged so as to pass through the center of the first mold part 811 in the Y-axis direction as viewed from the mold clamping direction.

[0129] The stationary mold 810 can have a first cylinder part 814. The first cylinder part 814 is a portion through which a portion of the sprue 802 passes. The first cylinder part 814 is provided at the center of the surface of the first mold part 811 opposite the movable mold 820. The first cylinder part 814 is inserted into a through-hole 812c that passes through the first cooling part 812 in the mold opening and closing direction. The first cooling part 812 moves along the first cylinder part 814. The first cylinder part 814 can function as a guide for the first cooling part 812. Also, at the time of mold clamping, the first cylinder part 814 can be compressed in the mold opening and closing direction, thereby transmitting the mold clamping force.

[0130] The stationary mold 810 can have a first back surface part 815. The first back surface part 815 is provided on the side opposite the movable mold 820 with the first mold part 811 as a reference. The first back surface part 815 can be a plate shape perpendicular to the mold opening and closing direction. The first back surface part 815 and the first mold part 811 are arranged with a space therebetween in the mold opening and closing direction, and the first cooling part 812 is arranged so as to be movable in both the mold opening direction and the mold closing direction in the space between the first back surface part 815 and the first mold part 811. Also, the first support part 813 and the first cylinder part 814 are arranged in the space between the first back surface part 815 and the first mold part 811. The first back surface part 815 is mounted to the stationary platen 110.

[0131] The stationary mold 810 can have a first drive part 819. The first drive part 819 relatively moves the first cooling part 812 and the first mold part 811. The first drive part 819 is, for example, a pneumatic cylinder, a hydraulic cylinder, or an electric motor. Alternatively, the first drive part 819 can not be a part of the stationary mold 810, but can be a part of the injection molding machine 10. Also, as the first drive part 819, the mold clamping motor 160 of the mold clamping device 100 or the drive mechanism 220 of the ejection device 200 shown in Figs. 1 and 2 can be used. Figure 1 and Figure 2 The mold clamping motor 160 of the mold clamping device 100 or the drive mechanism 220 of the ejection device 200 shown in Figs. 1 and 2 can be used.

[0132] In addition, in the present embodiment, the first cooling section 812 and the first support section 813 are provided in the fixed mold 810, but can be provided in the injection molding machine 10. The first cooling section 812 and the first mold section 811 can be provided between the fixed mold 810 and the fixed platen 110. The first cooling section 812 and the first mold section 811 can be relatively moved in the two directions of the opening direction and the closing direction between a position where they are apart from each other and a position where they are in contact with each other. The first mold section 811 is provided in the fixed mold 810.

[0133] The movable mold 820 has, for example, a second mold section 821, a second cooling section 822, and a second support section 823. The second mold section 821 is in contact with the fixed mold 810 at the time of clamping, and forms a part of a wall surface of the cavity space 801. The second mold section 821 is heated by the heat of the molding material filled in the cavity space 801. The temperature of the second cooling section 822 is adjusted to a temperature lower than the temperature of the second mold section 821 at the time of filling the molding material. The second support section 823 supports one of the second cooling section 822 and the second mold section 821 so as to be relatively movable with respect to the other. The second support section 823 functions as a guide. The second cooling section 822 and the second mold section 821 can be relatively moved in the two directions of the opening direction (for example, the negative direction of the X axis) and the closing direction (for example, the positive direction of the X axis) between a position where they are apart from each other and a position where they are in contact with each other.

[0134] The second mold section 821 is fixed with respect to the movable platen 120, and the second support section 823 supports the second cooling section 822 so as to be movable with respect to the movable platen 120. The second cooling section 822 is disposed in a space between the second mold section 821 and the movable platen 120. In addition, as will be described later in detail, as shown in FIG. 8, the second cooling section 822 can be fixed with respect to the movable platen 120, and at this time, the second support section 823 can support the second mold section 821 so as to be movable with respect to the movable platen 120. The second cooling section 822 and the second mold section 821 can be relatively moved in the two directions of the opening direction and the closing direction. Figure 4

[0135] ​The second mold section 821 and the second cooling section 822 can each be a plate shape perpendicular to the mold opening and closing direction. When viewed from the mold opening and closing direction, in order to cool the entire second mold section 821, it is preferable that the second cooling section 822 have a size equal to or greater than that of the second mold section 821. The second support section 823 can be a bar shape parallel to the mold opening and closing direction. The second support section 823 is inserted into a through-hole 822a that penetrates the second cooling section 822 in the mold opening and closing direction. A plurality of second support sections 823 can be provided. The second support section 823 is fixed with respect to the movable platen 120, and the second cooling section 822 moves along the second support section 823. The second support section 823 is compressed in the mold opening and closing direction at the time of mold closing, thereby transmitting the mold closing force. A plurality of second support sections 823 can be provided so that the mold closing force is uniformly applied to the second mold section 821. The second support section 823 is provided, for example, at four corners of the second mold section 821, respectively.

[0136] As shown in Figure 3 (A) and Figure 3 (B), the second cooling section 822 and the second mold section 821 can be separated at the time of filling of the molding material. That is, the second cooling section 822 and the second mold section 821 can be separated in the filling process. A space is formed between the second cooling section 822 and the second mold section 821, and the space restricts the movement of heat. The temperature of the second mold section 821 is higher, and the temperature of the wall surface of the cavity space 801 is higher, compared to the case where the second cooling section 822 and the second mold section 821 are in contact. As a result, the flowability of the molding material at the time of filling is good, and the shape and size of the cavity space 801 are easily transferred to the molded product. Therefore, the mold device 800 has good transferability. In order to improve the transferability of the mold device 800, it is not necessary to heat the second mold section 821 by the heating device at the time of filling of the molding material. However, the second mold section 821 can also be heated by the heating device at the time of filling of the molding material. Regardless, the temperature of the second mold section 821 is higher, and the temperature of the wall surface of the cavity space 801 is higher, compared to the case where the second cooling section 822 and the second mold section 821 are in contact.

[0137] It is preferable that the second cooling section 822 and the second mold section 821 be separated at least from the start to the end of the filling process. Furthermore, it is more preferable that the second cooling section 822 and the second mold section 821 still be separated at least a part of (preferably the entire) pressure maintaining process after the filling process. In the pressure maintaining process, if the temperature of the second mold section 821 is high, it is easy to supplement the molding material that is insufficient in the cavity space 801 due to shrinkage by cooling.

[0138] As shown in Figure 3As illustrated in FIG. C, the second cooling portion 822 can be in contact with the second mold portion 821 when the molding material is cooled. That is, the second cooling portion 822 can be in contact with the second mold portion 821 in the cooling process. The second cooling portion 822 takes heat from the second mold portion 821 by being in contact with the second mold portion 821. The second mold portion 821 can be cooled, and thus the cooling time until the molding material is solidified to the extent that the molding material can be taken out from the mold apparatus 800 can be shortened. The effect of shortening the cooling time can be significantly obtained particularly in the case where the molded product is a thick-walled member such as a lens.

[0139] For example, the second cooling portion 822 and the second mold portion 821 relatively move from a position where the second cooling portion 822 and the second mold portion 821 are apart from each other to a position where the second cooling portion 822 and the second mold portion 821 are in contact with each other when the pressure-holding process is switched to the cooling process. In addition, the second cooling portion 822 can be in contact with the second mold portion 821 from the middle of the cooling process. Even if the second cooling portion 822 is in contact with the second mold portion 821 from the middle of the cooling process, the cooling time can be shortened.

[0140] In the present embodiment, the second mold portion 821 and the second cooling portion 822 relatively move in the mold opening and closing direction. Compared to a case where the second cooling portion 822 moves in a direction orthogonal to the mold opening and closing direction as in Patent Literature 1, uneven cooling of the second mold portion 821 in a direction orthogonal to the mold opening and closing direction (i.e., the mold clamping direction) can be suppressed. As a result, uneven shrinkage of the molded product can be reduced, and deformation of the molded product can be reduced, and thus the transfer precision from the second mold portion 821 to the molded product can be improved.

[0141] The second cooling portion 822 has a flow path 822b inside for a refrigerant to flow. The temperature of the refrigerant is adjusted to a set temperature in advance by a temperature regulator not illustrated. The temperature regulator and the mold apparatus 800 are connected by a delivery pipe and a return pipe. The refrigerant is supplied to the flow path 822b via the delivery pipe. The refrigerant returns to the temperature regulator via the return pipe after flowing through the flow path 822b. The set temperature of the temperature regulator is set to be lower than the temperature of the second mold portion 821 when the molding material is filled. The refrigerant is, for example, water or oil.

[0142] In order to suppress uneven cooling of the second mold portion 821 in a direction orthogonal to the mold clamping direction, it is preferable that the flow path 822b be arranged so as to surround the central portion of the second mold portion 821 when viewed from the mold clamping direction. For example, it is preferable that the flow path 822b be arranged so as to be apart from the central portion of the second mold portion 821 in the Z-axis direction when viewed from the mold clamping direction. Also, it is preferable that the flow path 822b be arranged so as to be apart from the central portion of the second mold portion 821 in the Y-axis direction when viewed from the mold clamping direction.

[0143] The first cooling section 812 and the second cooling section 822 are preferably adjusted to the same temperature. The molded article can be uniformly cooled from both sides of the mold opening and closing direction, uneven cooling of the molded article can be reduced, and deformation of the molded article can be reduced, so that the transfer precision from the first mold section 811 and the second mold section 821 to the molded article can be improved. However, as long as the transfer precision can be improved, the first cooling section 812 and the second cooling section 822 can also be adjusted to different temperatures. The control device 700 acquires information on the shape and size of the molded article, and sets, proposes, or adjusts the temperature of the first cooling section 812 and the second cooling section 822 based on the acquired information.

[0144] The movable mold 820 can have a second back section 825. The second back section 825 is disposed on the side opposite to the fixed mold 810 with the second mold section 821 as a reference. The second back section 825 can be a plate shape perpendicular to the mold opening and closing direction. The second back section 825 and the second mold section 821 are disposed apart from each other in the mold opening and closing direction, and the second cooling section 822 is provided in the space between the second back section 825 and the second mold section 821 so as to be movable in both the mold opening direction and the mold closing direction. Further, the second support section 823 is provided in the space between the second back section 825 and the second mold section 821.

[0145] The movable mold 820 can have a second interval section 827 and a second mounting section 828 between the second back section 825 and the movable platen 120. The second interval section 827 is provided in a frame shape on the side opposite to the fixed mold 810 with the second back section 825 as a reference, and forms a space between the second back section 825 and the second mounting section 828. The ejector plate 826 is provided in the space so as to be movable in both the mold opening direction and the mold closing direction. The second mounting section 828 is mounted to the movable platen 120. The second mounting section 828 can be a plate shape perpendicular to the mold opening and closing direction.

[0146] The movable mold 820 can have a second drive section 829. The second drive section 829 relatively moves the second cooling section 822 and the second mold section 821. The second drive section 829 is, for example, a pneumatic cylinder, a hydraulic cylinder, or an electric motor. In addition, the second drive section 829 can not be a part of the movable mold 820, but can be a part of the injection molding machine 10. Further, as the first drive section 819, an existing device equipped in the injection molding machine 10, such as the clamp motor 160 of the clamp device 100 or the drive mechanism 220 of the ejector device 200 shown in Figs. 1 and 2, can also be used. Figure 1 and Figure 2 The second drive section 829 can be a part of the movable mold 820, or can be a part of the injection molding machine 10. Further, as the first drive section 819, an existing device equipped in the injection molding machine 10, such as the clamp motor 160 of the clamp device 100 or the drive mechanism 220 of the ejector device 200 shown in Figs. 1 and 2, can also be used.

[0147] In addition, in the present embodiment, the second cooling section 822 and the second support section 823 are provided in the movable mold 820, but can be provided in the injection molding machine 10. The second cooling section 822 and the second mold section 821 can be provided between the movable mold 820 and the movable platen 120. As long as the second cooling section 822 and the second mold section 821 are relatively movable in the two directions of the mold opening direction and the mold closing direction between the position where they are apart from each other and the position where they are in contact with each other. The second mold section 821 is provided in the movable mold 820.

[0148] Next, the operation of the mold device 800 will be described with reference to Figure 4 The mold device 800 according to the first modified example will be described. Hereinafter, the points different from the above-described embodiment will be mainly described. In the present modified example, the second cooling section 822 and the second mold section 821 are provided in the movable mold 820. Figure 1 and Figure 2 The mold clamping motor 160 of the mold clamping device 100 relatively moves the second cooling section 822 and the second mold section 821. The movable mold 820 of the present modified example has a second force applying section 824. The second force applying section 824 applies a force to the second mold section 821 in the mold closing direction (X-axis positive direction) with respect to the second cooling section 822 at the time of mold clamping. The second force applying section 824 is, for example, a coil spring, which is compressed at the time of mold clamping, and applies a force to the second mold section 821 in the mold closing direction (X-axis positive direction) with respect to the second cooling section 822 by the elastic restoring force thereof.

[0149] The second cooling section 822 is fixed with respect to the movable platen 120, and the second support section 823 supports the second mold section 821 so as to be movable with respect to the movable platen 120. The second force applying section 824 is fixed to the second support section 823 at one end thereof, and is fixed to the second mold section 821 at the other end thereof, for example. The second mold section 821 has a guide hole 821a into which the second support section 823 is inserted. The second force applying section 824 is also inserted into the guide hole 821a. In addition, the second force applying section 824 can be fixed to the second cooling section 822 at one end thereof, and be fixed to the second mold section 821 at the other end thereof.

[0150] At the time of mold clamping, the mold clamping motor 160 of the mold clamping device 100 advances the movable platen 120 against the elastic restoring force of the second force applying section 824 to a desired position. As shown in (A) of FIG. 12 and (B) of FIG. 13, the second cooling section 822 and the second mold section 821 can be apart from each other at the time of filling of the molding material. Then, if the mold clamping motor 160 further advances the movable platen 120, the second cooling section 822 and the second mold section 821 come into contact with each other. As shown in (C) of FIG. 12, the first cooling section 812 and the first mold section 811 can be in contact with each other at the time of cooling of the molding material. Figure 4 Figure 4 At the time of mold clamping, the mold clamping motor 160 of the mold clamping device 100 advances the movable platen 120 against the elastic restoring force of the second force applying section 824 to a desired position. As shown in (A) of FIG. 12 and (B) of FIG. 13, the second cooling section 822 and the second mold section 821 can be apart from each other at the time of filling of the molding material. Then, if the mold clamping motor 160 further advances the movable platen 120, the second cooling section 822 and the second mold section 821 come into contact with each other. As shown in (C) of FIG. 12, the first cooling section 812 and the first mold section 811 can be in contact with each other at the time of cooling of the molding material. Figure 4

[0151] ​​Although not shown, the fixed mold 810 may also include a first force-applying portion. During mold clamping, the first force-applying portion applies force to the first mold section 811 in the mold opening direction (negative X-axis direction) relative to the first cooling portion 812. The first cooling portion 812 is fixed relative to the fixed platen 110, while the first support portion 813 supports the first mold section 811 so that it can move relative to the fixed platen 110. In this case, the mold clamping motor 160 of the mold clamping device 100 can also move the first cooling portion 812 and the first mold section 811 relative to each other.

[0152] Next, refer to Figure 5 The mold device 800 involved in the second modification is described. The following mainly describes the differences from the above embodiment and the above first modification. In this modification, Figure 5 As shown in (A), when the first cooling portion 812 is separated from the first mold portion 811, the first cooling portion 812 is separated from the first cylinder portion 814, as shown in FIG. Figure 5 As shown in (B) , when the first cooling portion 812 is in contact with the first mold portion 811 , the first cooling portion 812 is in contact with the first cylindrical portion 814 .

[0153] The first barrel 814 is inserted into a through-hole 812c extending through the first cooling section 812 in the mold opening and closing direction. The through-hole 812c of the first cooling section 812 has a diameter that increases toward the mold opening direction (negative X-axis direction). Meanwhile, the first barrel 814 has an outer diameter that increases toward the mold opening direction. When the first cooling section 812 moves in the mold opening direction, the first cooling section 812 and the first barrel 814 come into contact. Furthermore, when the first cooling section 812 moves in the mold closing direction, the first cooling section 812 and the first barrel 814 separate.

[0154] like Figure 5 As shown in Figure (A), when filling the molding material, not only is the first cooling section 812 separated from the first mold section 811, but the first cooling section 812 is also separated from the first barrel section 814. This creates a space between the first cooling section 812 and the first barrel section 814, which limits heat transfer. Compared to a situation where the first cooling section 812 and the first barrel section 814 are in contact, the temperature of the first barrel section 814 is higher, and the flowability of the molding material in the gate 802 is improved. Furthermore, when filling the molding material, a thermal insulator can be placed in the space between the first cooling section 812 and the first barrel section 814.

[0155] like Figure 5As shown in (B), when the molding material is cooled, not only the first cooling portion 812 is in contact with the first mold portion 811, but also the first cooling portion 812 is in contact with the first cylinder portion 814. The first cooling portion 812 takes heat from the first cylinder portion 814 by being in contact with the first cylinder portion 814. The first cylinder portion 814 can be cooled, and thus the cooling time for which the molding material is solidified to the extent that the molding material can be removed from the mold device 800 can be shortened.

[0156] The above describes the embodiments of the mold device and the injection molding system according to the present application, but the present application is not limited to the above-described embodiments. Various modifications, corrections, replacements, additions, deletions, and combinations can be made within the scope of the technical solutions. These certainly belong to the technical scope of the present application.

Claims

1. A mold device provided with a fixed mold and a movable mold, a cavity space being formed between the fixed mold and the movable mold at the time of mold clamping, wherein the cavity space is a space filled with a preheated molding material, the fixed mold has a first mold portion that contacts the movable mold at the time of mold clamping and forms a part of a wall surface of the cavity space, a first cooling portion whose temperature is adjusted to a lower temperature than the temperature of the first mold portion at the time of filling the molding material, and a first support portion that supports one of the first cooling portion and the first mold portion so as to be relatively movable with respect to the other, the first cooling portion and the first mold portion are relatively movable in two directions of a mold opening direction and a mold closing direction between a position where they are apart from each other and a position where they contact each other, the movable mold has a second mold portion that contacts the fixed mold at the time of mold clamping and forms a part of a wall surface of the cavity space, a second cooling portion whose temperature is adjusted to a lower temperature than the temperature of the second mold portion at the time of filling the molding material, and a second support portion that supports one of the second cooling portion and the second mold portion so as to be relatively movable with respect to the other, and the second cooling portion and the second mold portion are relatively movable in the two directions of the mold opening direction and the mold closing direction between a position where they are apart from each other and a position where they contact each other.

2. The mold device according to claim 1, wherein the movable mold has a second drive portion that relatively moves the second cooling portion and the second mold portion.

3. The mold device according to claim 1, wherein the movable mold has a second force applying portion that applies a force to the second mold portion in the mold closing direction with respect to the second cooling portion at the time of mold clamping.

4. The mold device according to any one of claims 1 to 3, wherein the first support portion and the second support portion transmit a mold clamping force.

5. The mold device according to any one of claims 1 to 3, wherein the fixed mold has a first cylinder portion through which a part of a gate that supplies the molding material to the cavity space is inserted, the first cooling portion is apart from the first cylinder portion when the first cooling portion is apart from the first mold portion, and the first cooling portion contacts the first cylinder portion when the first cooling portion contacts the first mold portion.

6. An injection molding system provided with a mold device provided with a fixed mold and a movable mold, a cavity space being formed between the fixed mold and the movable mold at the time of mold clamping, and an injection molding machine that fills a preheated molding material in the cavity space of the mold device, wherein the fixed mold has a first mold portion that contacts the movable mold at the time of mold clamping and forms a part of a wall surface of the cavity space, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The fixed mold or the injection molding machine has a first cooling section whose temperature is adjusted to a temperature lower than that of the first mold section at the time of filling the molding material, and a first support section that supports one of the first cooling section and the first mold section so as to be relatively movable with respect to the other, The first cooling section and the first mold section are relatively movable in both the opening direction and the closing direction between a position where they are in contact with each other and a position where they are separated from each other, The movable mold has a second mold section that contacts the fixed mold at the time of the mold clamping and forms a part of a wall surface of the cavity space, The fixed mold or the injection molding machine has a second cooling section whose temperature is adjusted to a temperature lower than that of the second mold section at the time of filling the molding material, and a second support section that supports one of the second cooling section and the second mold section so as to be relatively movable with respect to the other, The second cooling section and the second mold section are relatively movable in both the opening direction and the closing direction between a position where they are separated from each other and a position where they are in contact with each other.

Images