Multi-mold system using runners

Abstract

To provide a runner that reduces resin leakage from the hot runner and reduces the possibility of air entering the molded product during continuous molding.SOLUTION: A runner 2 according to the present invention for supplying resin to a cavity includes: a sprue 4 supplied with resin from a nozzle 1 of an injection molding machine 200; a first pathway formed in the runner which flows from the nozzle to the first pathway when the nozzle connects to the sprue; and a first pin which moves to a first position to increase the size of the first pathway before the resin is supplied to the first pathway and moves to a second position to decrease the size of the first pathway before the nozzle separates from the sprue.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 62 / 776,384, filed December 6, 2018, which is incorporated by reference in its entirety.

[0002] TECHNICAL FIELD This application relates generally to reducing resin leakage from hot runners. [Background technology]

[0003] When the nozzle of the injection molding machine is separated from the hot runner, the pressure inside the hot runner decreases. Meanwhile, the resin inside the hot runner flows back from the hot runner. If the resin leaks out of the hot runner and the pressure inside the hot runner decreases, air may enter the hot runner and cause air bubbles in the molded part.

[0004] US Patent Application Publication No. 2006 / 0204610 discloses a spring-loaded sealing element attached inside the hot runner. When the nozzle of the injection molding machine and the hot runner are separated, the spring lengthens due to the pressure difference between the pressure inside the hot runner and the atmospheric pressure. The sealing element closes the opening of the resin supply path of the hot runner to prevent resin leakage.

[0005] When a spring element is used to seal the resin flow path, as in US 2006 / 0204610, the volume of resin in the spring and the volume of the material around the spring leak out of the hot runner. The more resin that leaks, the lower the pressure inside the hot runner. This can facilitate the formation of bubbles. As the leaked resin adheres to the separated nozzle side, the resin becomes long and thread-like between the nozzle and the hot runner. The thread-like resin can move to other places in the injection molding machine depending on the movement of the nozzle. This causes clogging and makes continuous molding impossible.

[0006] If multiple molds repeatedly move between the injection position of the injection molding machine and a position outside the injection molding machine, and the piping associated with the molds protrudes toward the inside of the injection molding machine as viewed from the molds, maintenance becomes difficult and the piping inside the injection molding machine may become easily clogged during movement.

[0007] What is needed is a multi-mold system that addresses and overcomes the problems discussed above. Summary of the Invention

[0008] Aspects of the present disclosure can reduce resin leakage from the hot runner, thereby reducing the possibility of resin being pinched in parts of the injection molding machine, stopping the injection molding machine, or air getting into the molded part during continuous molding.

[0009] According to at least one aspect of the present disclosure, a runner for supplying resin to a cavity includes a sprue configured to be supplied with resin from a nozzle of an injection molding machine, a first passage formed in the runner, the first passage flowing from the nozzle to the first passage when the nozzle contacts the sprue, and a first pin configured to move to a first position to increase a size of the first passage before resin is supplied to the first passage and to move to a second position to decrease a size of the first passage before the nozzle separates from the sprue. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a top view of an injection molding system.

[0011] [Diagram 2] FIG. 2 is a close-up view of the nozzle touch area where the nozzle of the injection molding machine connects to the sprue.

[0012] [Diagram 3] Figure 3 is an enlarged view of the hot runner nozzle and the resin molding parts of the mold.

[0013] [Figure 4A] , [Figure 4B] , [Figure 4C] 4A-4C show a portion of the molding operation process.

[0014] [Figure 5A] , [Figure 5B] , [Figure 5C] , [Figure 5D] 5A-5D show a portion of the molding operation process.

[0015] [Figure 6A] , [Figure 6B] , [Figure 6C] , [Figure 6D] 6A-6D show a portion of the forming operation process.

[0016] [Figure 7] FIG. 7 illustrates a portion of an injection molding machine, showing mold closing and mold opening.

[0017] [Figure 8A] , [Figure 8B] 8A-8B show the process of an injection molding system.

[0018] [Figure 9] FIG. 9 shows the positional relationship between the injection molding machine and the cart.

[0019] [Figure 10] FIG. 10 is a view of the stationary platen from the side of the first movable platen.

[0020] [Figure 11] FIG. 11 shows a partial perspective view of a mold A located inside the injection molding machine and a mold B located outside the injection molding machine.

[0021] [Figure 12A] , [Figure 12B] , [Figure 12C] , [Figure 12D] 12A to 12D show the coolant flow paths inside the mold.

[0022] [Figure 13] FIG. 13 shows the coolant flow paths inside the mold.

[0023] [Figure 14A] , [Figure 14B] , [Figure 14C] 14A-14C show the installation of the connector.

[0024] [Figure 15] FIG. 15 shows the installation of the connector.

[0025] [Figure 16A] , [Figure 16B] 16A-16B show a connecting element.

[0026] [Figure 17] FIG. 17 shows the drive arrangement for moving the valve pin and sprue pin.

[0027] [Figure 18A] , [Figure 18B] 18A-18B show a drive arrangement for moving the sprue pin.

[0028] [Figure 19A] , [Figure 19B] 19A-19B show a drive arrangement for moving the valve pin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. Note that the following embodiments are merely examples for carrying out the present invention, and can be appropriately modified depending on the configuration of the device to which the present invention is applied and various conditions. Therefore, the present disclosure is not limited to the following exemplary embodiments.

[0030] 1 is a top view of an injection molding system according to an exemplary embodiment, more specifically, a multi-mold system in which one mold is cooled while another mold ejects a molded part and injects resin into the other mold.

[0031] Injection molding machine cylinder 11 is an injection cylinder of injection molding machine 200, and enables the injection of resin into a mold through injection molding machine nozzle 1 by melting and injecting resin.

[0032] Injection molding machine nozzle 1 is attached to the end of injection molding machine 200. Resin is injected into hot runner 2 by applying pressure to the injection molding machine nozzle side 1 inside injection molding machine cylinder 11. Injection molding machine nozzle 1 has a pull-back (suck-back) function that can return resin remaining at the tip of injection molding machine nozzle 1 and resin leaking from the tip area of ​​injection molding machine nozzle 1 to the injection molding machine cylinder 11 side of the injection molding machine system.

[0033] The hot runner 2 maintains the resin temperature at a desired temperature. This avoids the cooling and waste of resin inside the runner after each injection into the mold, as occurs with commonly used cold runners, and therefore avoids waste of resin in the runner area. The hot runner 2 includes a sprue 4, a manifold 3, and a hot runner nozzle 5, and forms a flow path through which the resin passes from the injection molding machine cylinder 11 to the mold.

[0034] The sprue 4 includes a heater (not shown), is the contact point between the injection molding machine nozzle 1 and the mold, and is a part of the resin flow path. The manifold 3 includes a heater (not shown), is the contact point between the sprue 4 and the hot runner nozzle 5, and is a part of the resin flow path.

[0035] The hot runner nozzle 5 includes a heater (not shown) and can direct the resin flowing in from the manifold 3 into the cavity 14. The tip of the hot runner nozzle 5 is narrow and is equipped with a valve pin 6 that can open and close the opening at the tip. As such, each element has the function of maintaining the temperature, making it possible to perform continuous injection molding without discarding the resin located inside the runner.

[0036] Resin first passes from injection molding machine cylinder 11 through injection molding machine nozzle 1 and is injected into hot runner 2 by pressure from injection molding machine 200. The resin then passes through sprue 4 located inside hot runner 2, passes through manifold 3 and flows into hot runner nozzle 5. As will be explained below, the inner diameter of hot runner nozzle 5 is narrow, so it can be opened and closed by valve pin 6.

[0037] Resin supplied from the injection molding machine nozzle 1 passes through the resin flow path of the sprue 4, manifold 3, and hot runner nozzle 5 that constitute the hot runner 2, and flows into a cavity 14 that represents the void space inside the fixed side mold 12 and the movable side mold 13. The flow direction F indicates the direction in which the resin flows when it is injected from the injection molding machine cylinder 11 into the mold. As a result, a resin molded part 9 is formed in the cavity 14. The mold parting line 10 indicates the parting line between the fixed side mold 12 and the movable side mold 13. The cart 300 is installed along the X-axis, and a rail or actuator (not shown) for moving the mold is arranged on the cart 300.

[0038] As shown in FIG. 1, two types of resin molded parts are produced by injecting into a mold A and a mold B with a single injection molding machine 200. An opening 210 is formed on each side of the injection molding machine 200. The opening 210 is shown as a dotted line in FIG. 1. The mold A and the mold B are alternately inserted into and ejected from the injection molding machine 200 through the opening 210. Both the mold A and the mold B are composed of a fixed side mold 12 and a movable side mold 13, and resin molding is performed by injecting resin from a hot runner 2 into a cavity 14 between the fixed side mold 12 and the movable side mold 13. The mold A and the mold B are each connected to the hot runner 2.

[0039] The injection molding method of this exemplary embodiment will now be described.

[0040] First, molten resin is injected from injection molding machine nozzle 1 into mold A (or mold B) and held under pressure, and then injection molding machine nozzle 1 is separated from mold A. Mold A is transported outside injection molding machine 200 and cooled. In parallel, mold B is transported into injection molding machine 200, and injection molding machine nozzle 1 advances toward mold B and comes into contact with mold B.

[0041] Next, if there is a resin molded part in the mold B, it is removed, and after the resin molded part is removed, molten resin is injected into the mold B and held under pressure. After the injection molding machine nozzle 1 is separated from the mold B, the mold B is transported outside the injection molding machine 200 and cooled there. In parallel, the mold A is carried into the injection molding machine 200, where the injection molding machine nozzle 1 advances toward the mold A and comes into contact with the mold A. After that, the resin molded part is removed from inside the mold A, and molten resin is injected into the mold A and held under pressure.

[0042] As described above, the injection molding machine 200 repeatedly connects to and disconnects from a mold, and repeatedly carries the mold in and out of the injection molding machine 200 .

[0043] According to this exemplary embodiment, a resin molded product is removed from the injection molding machine 200, and while injecting resin into one mold, the resin injected into the other mold is cooled. This allows multiple molds, i.e., mold A and mold B, to be alternately cooled, and molded parts removed and injected, thereby improving production efficiency.

[0044] 2 shows a close-up view of nozzle contact area 25 where injection molding machine nozzle 1 connects to sprue 4. As previously mentioned, hot runner 2 connects to both mold A and mold B.

[0045] Distances a-c indicate the inner diameters of each of the above elements. Distance a indicates the inner diameter of a first resin flow passage 28 in the sprue 4. Distance b indicates the inner diameter of a second resin flow passage 29 in the sprue 4. Distance c indicates the inner diameter of a resin flow passage 22 in the injection molding machine nozzle 1. The relationship between the various inner diameters is c≦a <bである。

[0046] The cross-sectional area of ​​the second resin flow path 29 in the sprue 4 is larger than that of the first resin flow path 28 in the sprue 4, and is configured so that pressure loss of the resin injected from the injection molding machine nozzle 1 does not occur due to the resin flow path narrowing in the sprue 4. When the resin flows from the injection molding machine nozzle 1 to the hot runner 2, the resin flows in a direction from the first resin flow path 28 in the sprue 4 toward the second resin flow path 29 in the sprue 4. After the injection molding machine nozzle 1 separates from the sprue 4, the resin flows from the second resin flow path 29 in the sprue 4 toward the first resin flow path 28 in the sprue 4, which may cause the resin to leak from the sprue 4.

[0047] As shown in FIG. 2, when the inner diameter of the first resin flow path 28 in the sprue 4 is “a” and the inner diameter of the second resin flow path 29 in the sprue 4 is “b”, the relationship a < b is true. By making “a” smaller than “b”, the pressure for extruding the resin from the second resin flow path 29 in the sprue 4 into the first resin flow path 28 in the sprue 4 increases. As a result, it becomes difficult for the resin to leak from the sprue 4. Note that the shape of the resin flow path in the hot runner 2 is not limited to the above shape. In another exemplary embodiment, the resin flow path can be tapered toward the injection molding machine nozzle 1, where the inner diameter of the resin flow path can be gradually changed.

[0048] Let the outer diameter of the end portion 7a of the sprue pin 7 described later be d, and there is a relationship d = a. The sprue pin 7 closes the outlet of the sprue 4 to prevent the resin from leaking out of the sprue 4 or the resin from entering the sprue 4. When the sprue pin 7 moves toward the injection molding machine nozzle 1 side, since the inner diameters are equal (d = a), the sprue pin 7 can seal the injection molding machine nozzle 1. That is, the size of the resin flow path becomes smaller.

[0049] By making the sprue pin 7 smaller, the amount of resin extruded from the sprue 4 based on the movement of the sprue pin 7 can be reduced. Since the sprue pin 7 has a single rod shape and only moves toward the injection molding machine nozzle 1 side, when the sprue pin 7 is made smaller, only resin leakage occurs. The amount of resin leakage corresponds to the movement amount of the sprue pin 7. If the resin leakage is small, the possibility of the resin stretching into a filament or air entering the sprue 4 is reduced.

[0050] The outer diameter “d” of the end portion 7a of the sprue pin 7 can be made smaller to facilitate the movement of the sprue pin 7 inside the injection molding machine nozzle 1.

[0051] When the injection molding machine nozzle 1 contacts the sprue 4, the end of the sprue pin 7 on the injection molding machine nozzle 1 side is prevented from contacting the injection molding machine nozzle 1. Avoiding the collision with the sprue pin 7 when the injection molding machine nozzle 1 is attached to and detached from the mold can extend the life of the sprue pin 7.

[0052] In the above description, there is a diameter of the flow path, but the cross-sectional shape of the flow path does not necessarily have to be round. The relationship of the cross-sectional area of the flow path is that the cross-sectional area (the first resin flow path 28 inside the sprue) < the cross-sectional area (the second resin flow path 29 inside the sprue).

[0053] Figure 3 is an enlarged view of the hot runner nozzle 5 and the resin molding part 9 of the mold A or the mold B. The distances "e" and "f" indicate the inner diameters of the above elements. The distance "e" indicates the inner diameter of the first resin flow path 30 in the hot runner nozzle 5. The distance "f" indicates the inner diameter of the second resin flow path 31 in the hot runner nozzle 5. The relationship of the inner diameters is f < e. Thereby, due to the tip of the hot runner nozzle 5 becoming narrower, the hot runner nozzle 5 can be more easily closed together with the valve pin 6.

[0054] Figures 4A to 4C show how the sprue pin 7 moves. More specifically, Figures 4A to 4C show the sequence from when resin is injected from the injection molding machine nozzle 1 into the cavity 14 of the mold until the inflow of the resin stops. For the sake of explanation, the mold A is referred to, but the following is applicable to the mold B.

[0055] Figure 4A shows the state during resin supply from the injection molding machine nozzle 1 to the hot runner 2 and the mold A. When pressure is applied from the injection molding machine nozzle 1 to make the resin flow, the resin flows into the cavity 14 of the mold A as a result. This is because the resin flows from the direction with high resin pressure to the direction with low resin pressure inside the resin flow path of the hot runner 2 as indicated by the resin direction F.

[0056] FIG. 4B shows the state where the resin supply from the molding machine nozzle 1 has stopped and the valve pin 6 has closed the flow into the cavity 14. The valve pin 6 is a pin to prevent leakage of resin from the hot runner nozzle 5 and has high abrasion resistance. The valve pin 6 passes through the hot runner nozzle 5 and part of the manifold 3. Because the valve pin 6 moves perpendicular to the mold parting line 10, the valve pin 6 is subjected to pressure associated with the resin inside the hot runner nozzle 5 moving to the mold side where the pressure is lower, allowing the valve pin 6 to more reliably close the hot runner nozzle 5.

[0057] After the resin flows into the cavity 14, which is the empty space located between the molds as described above, the cavity 14 is filled and the flow of resin from the hot runner 2 stops. The flow of resin into the cavity 14 can be stopped by moving the valve pin 6 attached to the hot runner 2 in the direction of the flow of resin from the hot runner 2 to the cavity 14. The timing of stopping the flow of resin can be determined based on a predetermined time. The injection position or injection amount of resin can also be determined. The temperature of the flowing resin is typically between 170 and 400°F, but the temperature can be changed depending on the shape of the molded part. The flow rate of the resin may vary depending on the melt viscosity of the resin, etc. After the flow of the resin stops, cooling of the resin molded part 9 begins.

[0058] The movement of the valve pin 6 can be based on receiving a signal from the injection molding machine 200 or from outside the injection molding machine 200. The movement of the valve pin 6 is driven pneumatically. The movement of the valve pin 6 occurs by applying pressure to a pressure receiving area attached to the top of the valve pin 6. The drive arrangement for moving the valve pin 6 is described in detail below.

[0059] During resin injection, the resin pressure generated in the injection molding machine nozzle 1, hot runner 2, and cavity 14 is in the following order: injection molding machine nozzle 1 > hot runner 2 > cavity 14. Pressure loss may occur due to friction between the resin and the flow path.

[0060] When the valve pin 6 stops the resin flow, the pressure in the injection molding machine nozzle 1, hot runner 2, and cavity 14 becomes such that (injection molding machine nozzle 1 = hot runner 2) > cavity 14.

[0061] 4C shows the state where the sprue pin 7 has moved to the injection molding machine nozzle 1 side to prevent resin from leaking out of the sprue 4 side of the hot runner 2. The sprue pin 7 can close the inlet of the sprue 4 and is positioned to move within the sprue 4 and manifold 3. As described above with respect to the valve pin 6, the sprue pin 7 can create a stronger seal for the outlet of the sprue 4 due to the strength of the resin leaking out of the hot runner 2 where the pressure is lower. The drive configuration for moving the sprue pin 7 will be described in detail below.

[0062] By moving the sprue pin 7 attached to the hot runner 2 toward the injection molding machine nozzle 1, it is possible to prevent the resin present inside the hot runner 2 from flowing back out of the hot runner 2. If the resin leaks out of the hot runner 2, air may enter the hot runner 2, and the resin containing the air that enters the cavity 14 may form a molded resin part 9 containing air. By preventing the outflow of the resin with the sprue pin 7, it is possible to prevent air from entering the molded part.

[0063] As described above, there is a possibility that an amount of resin equivalent to the amount of movement of sprue pin 7 from the state shown in Fig. 4B to the state shown in Fig. 4C will be pushed out from hot runner 2. After sprue pin 7 moves, a pullback (suck back) is performed to draw the resin inside injection molding machine nozzle 1 into hot runner 2, thereby preventing additional resin leakage from injection molding machine 200. The inlet on the sprue 4 side through which resin flows in from injection molding machine nozzle 1 is sealed by sprue pin 7, and hot runner nozzle 5 is sealed by valve pin 6. This makes it possible to maintain a constant pressure inside hot runner 2.

[0064] The timing of the sealing of the valve pin 6 illustrated in FIG. 4B and the timing of the sealing of the sprue pin 7 illustrated in FIG. 4C may be reversed or may occur simultaneously.

[0065] The pressure of the injection molding machine nozzle 1, hot runner 2, and resin in cavity 14 is hot runner 2 > injection molding machine nozzle 1 ≧ cavity 14 when the inside of hot runner 2 is sealed with valve pin 6 and sprue pin 7 (FIG. 4C). The pressure of the injection molding machine nozzle 1 is lower than the pressure of the hot runner 2 because the pressure is reduced by performing pullback. The pressure applied from the hot runner 2 inside cavity 14 is eliminated, and when the resin starts to harden, the pressure is further reduced.

[0066] FIG. 17 shows an outline of a drive configuration for moving the valve pin 6, the valve pin 6, and the sprue pin 7. The injection molding system includes a controller 70, an air compressor 80, an air valve unit 81, and an air pipe 82. The air valve unit 81 is located between the air compressor 80 and the air pipe unit 82. The air compressor 80 generates compressed air for moving the valve pin 6, the valve pin 6, and the sprue pin 7. The air pipe 82 includes a plurality of air pipes, while the air valve unit 81 includes a plurality of air valves corresponding to the plurality of air pipes. The controller 70 controls the air valve unit 81 (i.e., each of the plurality of air valves) regardless of whether the compressed air generated by the air compressor 80 is supplied to each air pipe of the air pipe 82.

[0067] 18A-18B show a drive configuration for moving the sprue pin 7. In FIG. 18, for simplicity of explanation, members other than the manifold 3, sprue 4, and sprue pin 7 are omitted. Air pipes 91 and 92 are installed in the mold A. The air pipe 91 is connected to one side of the space 90, and the air pipe 92 is connected to the other side of the space 90. The space 90 is a space in which the sprue pin 7 moves. The air pipes 91 and 92 are connected to some of the multiple air pipes (air pipe unit 82) at the outlet of the mold A. The same type of air pipe is also installed in the mold B.

[0068] In Fig. 18A, the controller 70 controls the air valve unit 81 so that air is supplied through the air pipe 92 but not through the air pipe 91. In this case, the sprue pin 7 moves to close the inlet of the sprue 4, as shown in Fig. 18A. In Fig. 18B, the controller 70 controls the air valve unit 81 so that air is supplied through the air pipe 91 but not through the air pipe 92. In this case, the sprue pin 7 moves to open the inlet of the sprue 4, as shown in Fig. 18B.

[0069] 19A and 19B show a drive configuration for moving the valve pin 6. In FIG. 19, for simplicity of explanation, members other than the manifold 3, the hot runner nozzle 5, and the valve pin 6 are omitted. Air pipes 94 and 95 are installed in the mold A. The air pipe 94 is connected to one side of the space 93, and the air pipe 95 is connected to the other side of the space 93. The space 93 is a space in which the valve pin 6 moves. The air pipes 94 and 95 are connected to some of the multiple air pipes (air pipe unit 82) at the outlet of the mold A. The same type of air pipe is also installed in the mold B.

[0070] In FIG. 19A, the controller 70 controls the air valve unit 81 so that air is supplied through air pipe 94 but not through air pipe 95. In this case, the valve pin 6 moves to close the outlet of the hot runner nozzle 5, as shown in FIG. 19A. In FIG. 19B, the controller 70 controls the air valve unit 81 so that air is supplied through air pipe 95 but not through air pipe 94. In this case, the valve pin 6 moves to open the outlet of the hot runner nozzle 5, as shown in FIG. 19B. Although FIGS. 19A-19B illustrate a drive arrangement for moving the valve pin 6, the same drive arrangement is applicable for moving the valve pin 6.

[0071] As described above, the injection molding system includes an actuator for moving the valve and the sprue pin. The actuator enables the sprue pin 7 to move before the injection molding machine nozzle 1 separates from the hot runner 2. This allows the injection molding machine nozzle 1 to pull back the resin extruded from the hot runner 2 by the movement of the sprue pin 7.

[0072] The drive arrangement for moving the valve pins and sprue pins is not limited to the above-mentioned manner, in another exemplary embodiment, a servo motor or a hydraulic system can be used to move the valve pins and sprue pins.

[0073] 5A to 5D show the separation and connection of the injection molding machine nozzle 1 and the hot runner 2. Figures 5A and 5B show a method for separating the injection molding machine nozzle 1 and the hot runner 2, and a method for moving the separated hot runner 2 and the mold A connected to the separated hot runner 2 to the outside of the injection molding machine 200.

[0074] 5A shows the separation of the injection molding machine nozzle 1 and the hot runner 2. The direction in which the injection molding machine nozzle 1 separates from the hot runner 2 and moves is the direction shown by the arrow D1.

[0075] 5B shows the direction in which hot runner 2 and mold A move to the outside of injection molding machine 200. More specifically, hot runner 2 and mold A move in the direction of arrow D2. The direction of arrow D1 (see FIG. 5A) and the direction of arrow D2 are perpendicular to each other. The direction in which hot runner 2 and mold A move is different from the direction in which hot runner 2 and mold B move to the outside of injection molding machine 200.

[0076] More specifically, mold A and mold B are positioned along an axis (e.g., the X-axis). If mold A is located in the positive axial direction of mold B, the movement direction outside injection molding machine 200 is the positive direction with respect to mold A and the negative direction with respect to mold B. If the positional relationship between mold A and mold B is reversed, mold A can be moved outside injection molding machine 200 by moving mold A in the negative direction and mold B in the positive direction.

[0077] 5C and 5D show how to reconnect the injection molding machine nozzle 1 and the hot runner 2.

[0078] 5C shows how mold A, which was outside injection molding machine 200, moves inside injection molding machine 200. Because mold A and hot runner 2 moved in the direction of arrow D2 when they moved outside injection molding machine 200, they move in the direction of arrow D3, which is the opposite direction to the direction of arrow D2 when they re-enter injection molding machine 200.

[0079] FIG 5D shows how the injection molding machine nozzle 1, hot runner 2, and mold A are reconnected after the hot runner 2 and mold A move into the injection molding machine nozzle 1. The injection molding machine nozzle 1 moves toward the hot runner 2 and mold A (in the direction of arrow D4). After the injection molding machine nozzle 1 moves as shown in FIG 5D, the injection molding machine nozzle 1 and sprue 4 connect as shown in FIG 4C.

[0080] 6A shows the state after the injection molding machine nozzle 1 and the hot runner 2 are reconnected. After the injection molding machine nozzle 1 and the hot runner 2 are reconnected, the mold parting line 10 is opened and the resin molded part 9 is removed.

[0081] FIG. 6B shows the condition after the mold parting line 10 has been reclosed.

[0082] 6C shows the state where the resin flow path of the sprue 4 is opened by moving the sprue pin 7 in the opposite direction of the injection molding machine nozzle 1. By moving the sprue pin 7 attached to the hot runner 2 in the opposite direction of the injection molding machine nozzle 1, the resin flowing from the injection molding machine nozzle 1 can be made to flow downstream.

[0083] Figure 6D shows the valve pin 6 moving towards the injection molding machine nozzle 1 to open the hot runner nozzle 5 and inject resin into the cavity 14. The timing of the closing of the valve pin 6 shown in Figure 6D and the timing of the sprue pin 7 shown in Figure 6C can be reversed or can be simultaneous.

[0084] The various processes depicted in Figures 4A-4C, 5A-5D, and 6A-6D show the flow of an injection molding operation.

[0085] FIG. 7 shows a portion of an injection molding machine 200 that performs mold closing and opening.

[0086] The injection molding machine cylinder 11 is composed of a screw 51, a heating barrel 56, an injection molding machine nozzle 1, and a material input hopper 52. By retracting and rotating the screw 51, the resin material is sent to the injection molding machine nozzle 1 side. The heating barrel 56 heats the resin that has passed through the injection molding machine nozzle 1. The gap between the screw 51 and the heating barrel 56 narrows toward the injection molding machine nozzle 1. The input of resin to the injection molding machine cylinder 11 and the injection molding machine nozzle 1 is called resin scaling.

[0087] Resin scaling allows resin to be charged into the material charging hopper 52, and resin can be sent to the injection molding machine nozzle 1 side by retracting and rotating the screw 51. At this point, when the resin is sandwiched between the screw 51 and the inner wall of the heated barrel 56, the resin is melted by the heat generated by the heated barrel 56 and the shear heat applied to the resin by the rotation of the screw 51. In the injection molding machine 200, an arbitrarily determined amount of resin material is melted. The arbitrarily determined amount varies for each mold.

[0088] Scaling is complete when resin accumulates between the injection molding machine nozzle 1 and the screw 51. A shutoff screw 49 closes the injection molding machine nozzle 1 to ensure that no resin leaks out of the injection molding machine nozzle 1.

[0089] The fixed platen 53 and the first movable platen 54 are platens for closing the mold. This mold is sandwiched between the fixed platen 53 and the first movable platen 54. As seen from the mold, the fixed platen 53 is on the injection molding machine nozzle 1 side and does not move toward the mold. As seen from the mold, the second movable platen 55 is located on the opposite side of the injection molding machine nozzle 1. By moving the first movable platen 54, the fixed-side mold 12 and the movable-side mold 13 can be closed together with the fixed platen 53.

[0090] Even if the hot runner 2 moves along a direction perpendicular to the plane of the nozzle contact area 25 (see FIG. 2) or along the direction of movement of the injection molding machine nozzle 1, the sprue pin 7 prevents the resin from lengthening between the injection molding machine nozzle 1 and the sprue 4.

[0091] As described above, the installation of the sprue pin 7 can pull back the resin that leaks out of the hot runner 2 during the separation of the injection molding machine nozzle 1, reducing the possibility of the resin forming threads in the injection molding machine 200. Since less resin leaks out of the hot runner 2, it can also reduce the increase in the amount of resin or resin leaking between the internal elements of the injection molding machine 200 and causing clogging. More specifically, it increases the possibility of continuous molding without interruption. It can also reduce the possibility of forming resin molded parts that contain air.

[0092] When the valve pin 6 is closed first and then the sprue pin 7 is closed, the resin under high pressure located in the resin flow path moves to the injection molding machine nozzle 1 before the sprue pin 7 is closed. After the sprue pin 7 is closed, a pullback is performed to pull the resin located inside the hot runner 2 into the injection molding machine nozzle 1, thereby preventing resin leakage from the injection molding machine 200 and the hot runner 2.

[0093] If the sprue pin 7 is closed first and then the valve pin 6 is closed, the resin under high pressure located inside the resin flow path moves to the cavity 14 before the valve pin 6 is closed. In this case, it is possible to reliably prevent resin leakage from the hot runner 2, but since too much resin under high pressure flows into the cavity 14, the resin molded part 9 will contain more than a predetermined amount of resin. This may result in a deterioration in the precision of the molded part.

[0094] Closing the sprue pin 7 and the valve pin 6 simultaneously can reduce resin leakage and deterioration of the molded part. This can be achieved because the resin under high pressure located inside the resin flow path can move to the injection molding machine nozzle 1 and cavity 14.

[0095] In the above embodiment, it has been described that the sprue pin 7 is moved so that the injection molding machine nozzle 1 closes to reduce the resin flow path. By moving the sprue pin 7, it is possible to reduce the cross-sectional area of ​​the flow path, to reduce the supply of resin to other parts of the injection molding machine 200, or to reduce the reception of resin from other parts of the injection molding machine 200. In particular, the cross-sectional area of ​​the flow path of the sprue 4 is reduced, less resin flows into the sprue 4, and / or less resin leaks from the sprue 4. The cross-sectional area of ​​the flow path is the area of ​​the XZ plane in FIG. 1.

[0096] To reduce the amount of resin leakage, the sprue pin 7 can be used to move along the boundary between the first resin flow path 28 and the second resin flow path 29. If the height of the first resin flow path 28 in the Y direction is small, the cross-sectional area of ​​the tip of the sprue pin 7 can be designed to be larger than the cross-sectional area of ​​the first resin flow path 28. In this case, the sprue pin 7 moves to the boundary between the first resin flow path 28 and the second resin flow path 29, so that the sprue pin 7 can completely close the flow path of resin in the second resin flow path 29. The sprue pin 7 becomes an obstacle to the resin that passes through the sprue 4 and reaches the cavity 14, thereby reducing the cross-sectional area of ​​the flow path of the resin.

[0097] When the injection process is performed, the sprue pin 7 is in a position where the cross-sectional area of ​​the resin flow path is larger than the cross-sectional area of ​​the resin flow path when the sprue pin 7 moves toward the injection molding machine nozzle 1. For example, the first position of the sprue pin 7 is the position of the sprue pin 7 in FIG. 4A, and the second position of the sprue pin 7 is the position of the sprue pin 7 in FIG. 4C. When the sprue pin 7 moves from the first position to the second position, the amount of resin flowing through the resin flow path decreases. When the sprue pin 7 moves from the second position to the first position, the amount of resin flowing through the resin flow path increases.

[0098] The sprue pin 7 is in a first position from when the injection molding machine nozzle 1 contacts the sprue 4 until injection into the mold is completed.

[0099] The structure for closing the injection molding machine nozzle 1 is not limited to the sprue pin 7. A lid that covers the inlet of the sprue 4 can also be applied. This lid can slide upward from the inlet of the sprue 4 when the injection molding machine nozzle 1 disengages from the sprue 4. This lid can slide out from the inlet of the sprue 4 when the injection molding machine nozzle 1 contacts the sprue 4.

[0100] 2 also enables the reduction of the resin flow path. In this case, the sprue 4 moves along the X direction to reduce the cross-sectional area of ​​the first resin flow path 28 or the second resin flow path 29.

[0101] The shape of the tip of the sprue 4 is not limited to a cylindrical shape, but may be a cone shape, a triangular pyramid shape, etc. Regardless of the shape of the sprue 4, the sprue pin 7 comes into contact with the inside of the sprue 4 and stops at a certain point.

[0102] The sprue pin 7 must keep the sprue 4 closed at least until the resin cools to prevent the molten resin from leaking out. For example, the sprue pin 7 continues to reduce the flow path of the resin until the mold is moved out of the injection molding machine 200.

[0103] The valve pin 6 and shutoff nozzle 49 move to reduce the flow path of the resin. This means that the cross-sectional area of ​​the flow path in the hot runner nozzle 5 is reduced, resulting in less resin flowing into the cavity 14 and / or less resin leaking out of the hot runner nozzle 5. The cross-sectional area of ​​the flow path in the injection molding machine nozzle 1 is reduced, resulting in less resin flowing into the sprue 4 and / or leaking out of the injection molding machine nozzle 1.

[0104] 1-7 show details of a mold according to this exemplary embodiment. We now provide an example of the operation of the injection molding system.

[0105] First, the device configuration of the injection molding system of this embodiment will be described with reference to FIGS. 9 to 11, and the process of the injection molding system of this embodiment will be described with reference to FIG.

[0106] Fig. 9 shows the positional relationship between the injection molding machine 200 and the cart 300 of this embodiment. As shown in Fig. 9, the injection molding machine 200 includes an injection device 201 composed of an injection molding machine nozzle 1 and an injection molding machine cylinder 11, a mold clamping device (mold clamping device) 58, and a removal device that removes molded parts. The injection device 201 and the mold clamping device 58 are attached in the Y direction.

[0107] The mold clamping device 58 performs mold clamping and opens and closes the molds A and B, and is a toggle type mold clamping device in this embodiment. The fixed platen 53, the first movable platen 54, and the second movable platen 55 are arranged in this order in the Y direction inside the clamping device 58. A plurality of tie bars 59 (four in this embodiment) are inserted through the platens 53 to 55. Each tie bar 59 is a shaft extending in the Y direction with one end fixed to the fixed platen 53. Each tie bar 59 is inserted into a respective through hole formed in the first movable platen 54. The other end of each tie bar 59 is fixed to the second movable platen 55 via an adjustment mechanism 55a. The first movable platen 54 and the second movable platen 55 can move in the Y direction perpendicular to the frame 203. The fixed platen 53 is fixed to the frame 203. The frame 203 includes a frame of the cart 300, and supports the actuator 18 and a plurality of rollers 240.

[0108] A toggle mechanism (not shown) is provided between the first movable platen 54 and the second movable platen 55. The toggle mechanism causes the first movable platen 54 to move forward / backward in the Y direction relative to the second movable platen 55, i.e., relative to the fixed platen 53.

[0109] The injection molding machine 200 includes sensors (not shown) for measuring the clamping force. In this embodiment, each sensor is a strain gauge installed on the tie bar 59, and detects the strain of the tie bar 59 to calculate the clamping force.

[0110] The adjustment mechanism 55a is supported by a nut 55b so as to be freely rotatable on the second movable platen 55, and includes a motor 55c as a drive source and a transmission mechanism (a belt transmission mechanism in this embodiment) that transmits the drive force of the motor 55c to the nut 55b. Each tie bar 59 passes through a hole formed in the second movable platen 55 and engages with the nut 55b. By rotating the nut 55b, the engagement position of the nut 55b and the tie bar 59 in the Y direction changes. That is, the position at which the second movable platen 55 is fixed to the tie bar 59 changes. This makes it possible to change the space between the second movable platen 55 and the fixed platen 53, and to adjust the clamping force, etc. The amount of rotation of the motor 55c is detected by a sensor (not shown) such as a rotary encoder. By driving the motor 55c while detecting the amount of rotation of the motor 55c, the position at which the second movable platen 55 is fixed to the tie bar 59 can be changed with high precision to any position relative to the initial position.

[0111] A mold is injected from the injection molding machine 200 by moving to the area (molding operation position) between the fixed platen 53 and the first movable platen 54. Mold A or mold B brought into the area is sandwiched between the fixed platen 53, the first movable platen 54, and the second movable platen 55. Opening and closing are performed based on the movement of the movable mold 13 via the movement of the first movable platen 54.

[0112] Molds A and B are a pair belonging to a fixed mold 12 and a movable mold 13, and are opened and closed relative to the fixed mold 12. A molded part is formed by injecting molten resin into a cavity formed between the fixed mold 12 and the movable mold 13. Fixed plates (clamp plates) 12a and 13a are fixed to the fixed mold 12 and the movable mold 13, respectively. The fixed plates 12a and 13a are used to lock the molds A and B in the area (mold clamping position) between a fixed platen 53 and a first movable platen 54 of the injection molding machine 200.

[0113] In addition, an automatic closing unit 301 for maintaining a closed state between the fixed mold 12 and the movable mold 13 is attached to the mold A and the mold B. The automatic closing unit 301 makes it possible to prevent the molds A and B from opening after they are discharged from the injection molding machine 200. In this embodiment, the automatic closing unit 301 keeps the molds A and B in a closed state by using a magnetic force. The automatic closing unit 301 is installed at a plurality of locations along the opposing surfaces of the fixed mold 12 and the movable mold 13. In this embodiment, the automatic closing unit 301 is a combination of an element on the side of the fixed mold 12 and an element on the side of the movable mold 13. The combination of these elements is, for example, a combination of a permanent magnet and a magnetic material such as iron, or a pair of permanent magnets.

[0114] In another exemplary embodiment, a mechanism using elastic deformation of plastic or the like made of metal and spring, or a mechanical mechanism can be used for the self-closing unit 301. Using magnetic force is advantageous because it allows the mold to return to a closed state when it is opened slightly. In some self-closing units, the closing force is generally small in relation to the clamping force of the mold clamping device, and as a result, the mold opens slightly due to the resin pressure in the mold. With a self-closing unit using magnetic force, even if the mold opens slightly, it is possible to reclose the mold in conjunction with the reduction in the resin pressure in the mold. At this time, the close contact between the mold and the resin in the mold is maintained, and the quality of the molded part is stable.

[0115] As for the self-closing unit 301, two or more pairs, preferably four pairs, can be installed for one of the molds (A and B). A pair of self-closing units can keep a space between about 0.1 mm to several mm open when the molds A and B are in a closed state. This can prevent a sudden change in magnetic force when transitioning from an open state to a closed state, and thus can maintain a balanced closed state.

[0116] An actuator 18, which is a driving source for moving the molds A and B, a link 17 between the actuator and the mold B, a link 15 between the molds B and A, and rollers 240 are attached to a cart 300. Only one actuator 18 is installed on the mold B side. The two molds can be moved together with the actuator 18 via the link 15. The rollers 240 are installed along the X axis and enable the molds A and B to enter and exit the injection molding machine 200. The multiple rollers 240 form two rows, each separated in the Y direction.

[0117] The rollers 240 include two types of rollers, rollers 240Z and rollers 240Y, which rotate on two different axes. The rollers 240Z rotate around an axis in the Z direction, and the rollers 240Y rotate around an axis in the Y direction. The rollers 240Z guide the movement of the molds A and B in the X direction, contact the side surfaces of the molds A and B (side surfaces of the fixed plates 12a and 13a), and support the molds A and B from the side surfaces. The rollers 240Y guide the movement of the molds A and B in the X direction, contact the bottom surfaces of the molds A and B, and support the molds A and B from below.

[0118] The controller 70 controls the injection molding machine 200, the molds A and B, and the cart 300. The control unit 70 includes, for example, a processor such as a CPU, a storage device such as a RAM, a ROM, and a hard disk, and an interface connected to sensors and actuators. The processor executes a program stored in the storage device. An example of a program (control) executed by the controller 70 will be described below.

[0119] 10 is a view of the fixed platen 53 viewed from the side of the first movable platen 54. An opening area 62 through which the injection molding machine nozzle 1 moves back and forth is formed in the central area of ​​the fixed platen 53.

[0120] Inside the injection molding machine 200, there is no roller installed in series with the roller 240Z, but the roller 63 is installed in series with the roller 240Y. The rollers 63 and 240Y may be the same size or may be different sizes. The roller 63 is arranged on the outside of the injection molding machine 200 and is approximately linear on the X-axis aligned with the roller 240Y. The roller 63 allows the molds A and B to move smoothly from the outside of the injection molding machine 200 to the inside of the injection molding machine 200.

[0121] Typically, when a roller (not shown) that rotates in a circumferential direction in the Z-axis direction on a substantially straight line on the X-axis aligned with roller 240Z is installed, a gap the size of roller 240Z is created between fixed platen 53 and fixed plates 12a, 13a. Therefore, when rotating around the Z-axis installed continuously with roller 240Z, a roller (not shown) cannot be installed inside injection molding machine 200.

[0122] When the molds A and B move inside the injection molding machine 200, if the XZ plane of the fixed platen 53 comes into contact with the XZ plane of the fixed plates 12a and 13a, frictional force may make it difficult for the molds A and B to move in the X direction, or wear may occur due to rubbing. For this reason, the inner surface of the fixed platen 53 has grooves 61 extending in the X-axis direction. Two rows of grooves 61 are provided that are separated from each other in the perpendicular direction. Each groove 61 includes a roller unit 61a.

[0123] The roller unit 61a supports the roller SR so that the roller SR rotates freely. The roller SR rotates around a rotation axis in the Z direction and guides the movement of the dies A and B in the X direction. The roller SR comes into contact with the outer surfaces of the dies A and B (the outer surfaces of the fixed plates 12a and 13a) and supports the dies A and B from the side surfaces. The roller unit 61a is positioned at a position where the roller SR protrudes from the groove 61 by the bias of a spring (not shown). In this embodiment, multiple examples of the roller unit 61a and the roller SR are used.

[0124] During clamping, the roller unit 61a is retracted into the groove 61 and positioned so that the roller SR does not protrude from the groove 61. The roller unit 61a can prevent the inner surfaces of the molds A, B and the fixed platen 53 from coming into contact with and damaging the inner surfaces when switching between the molds A and B. The roller unit 61a does not interfere with the inner surfaces of the fixed platen 53 and the molds A, B that are closed during clamping.

[0125] The roller supports 64 are attached to both sides in the X direction of the fixed platen 53. The rollers SR are supported by the roller supports 64. The roller supports 64 and the rollers SR enable the molds A and B to be transported faster and smoother when being transported between the inside of the injection molding machine 200 and the outside of the injection molding machine 200.

[0126] A plurality of fixing mechanisms 60 (hereinafter referred to as "clamps") for fixing the stationary mold 12 to the stationary platen 53 are disposed on the stationary platen 53. Each clamp 60 has an engagement portion 60a that engages with the stationary plates 12a and 13a, and a built-in actuator (not shown) that moves the engagement portion 60a between an engaged position and a disengaged position. The actuator is a fluid actuator, such as a hydraulic actuator or a pneumatic actuator. A fluid actuator is advantageous in situations where multiple molds are frequently arranged alternately.

[0127] In this embodiment, an electromagnetic clamp is used. The electromagnetic clamp can magnetize or demagnetize the magnetic body (magnetic material) inside the coil that is present in the object to be clamped in a relatively short time by passing a current through the coil. This makes it possible to attach and detach the mold in this embodiment.

[0128] For the first movable platen 54, similar to the fixed platen 53, rollers SR and clamps 60 are used to fix the second movable mold 55.

[0129] Fig. 11 shows a partial perspective view of a mold A located inside the injection molding machine 200 and a mold B located outside the injection molding machine 200. More specifically, Fig. 11 illustrates a view of the molds A and B from the side where the second movable platen 55 (see Fig. 9) is located and from the side where the actuator 18 is located. The molds A and B can be moved from the outside of the injection molding machine 200 to the inside of the injection molding machine 200 based on the rotation of the rollers 240Y and 240Z.

[0130] When replacing mold B, it can be removed and installed from position 310 shown in FIG. 11. Mold B waits at position 310 on cart 300 while being cooled. When replacing mold A, it can be removed and installed from a position on the opposite side of actuator 18 on cart 300. Mold B and actuator 18 are connected by link 17, and mold A and mold B are connected by link 15. This allows mold A and mold B to move together. Note that the mold replacement position is not limited to the one described above, and it may be performed from above, or both molds A and B may be replaced on the actuator 18 side.

[0131] The molds A and B described in this embodiment can be frequently replaced depending on the type of molded parts. In recent years, the number of molds produced in small quantities, as well as the number of molds produced at one time, has increased. Therefore, producing two types of molded parts in one operation of the injection molding machine system has a great advantage in manufacturing work space.

[0132] As described above, the injection molding machine system allows for production with frequent replacement of various molds. To achieve this, the coolant flow passages are used to flow coolant for cooling the resin, and the conduits are used to transmit electrical signals for controlling the valve pins 6 and sprue pins 7 in the molds A and B. The coolant flow passages and conduits pass through the insides of the molds A and B and are connected to a coolant supply device and a controller 70 (see FIG. 9) located outside the molds A and B, respectively. In this embodiment, the coolant is water, but any liquid can be used as long as it provides a similar cooling effect.

[0133] 12A-12D, 13, 14A-14B, and 15, the structure of the coolant channels and conduits for molds A and B of this exemplary embodiment will be described.

[0134] 12A to 12D and 13 show the structures of the cooling liquid flow paths of the molds A and B. FIG.

[0135] FIG. 12A shows a perspective view of mold A or B. Cross section M is parallel to the YZ plane. FIG. 12B-FIG. 12D show views of mold A or mold B from cross section M. As mentioned above, the resin molded part 9 is located in the central region of the mold. Liquid inlet 20i and liquid outlet 20o are associated with cooling liquid flow passage 20, and liquid inlet 21i and liquid outlet 21o are associated with cooling liquid flow passage 21, and are provided in different planes of the mold along the X axis, i.e., the direction in which the mold moves. Liquid inlet 20i, liquid outlet 20o, liquid inlet 21i, and liquid outlet 21o are considered as piping interfaces for the mold.

[0136] Also, the coolant passages 20, 21 follow separate paths within the mold such that liquid flowing through one coolant passage does not exit through the other coolant passage which may have external plumbing attached, but is unused. In another exemplary embodiment, liquid is prevented from leaking from the unused coolant passage, and therefore two separate passages are not required.

[0137] By providing the cooling liquid flow paths 20, 21 in the fixed mold 12, the direction in which the cooling liquid flow paths 20, 21 move is limited to only the X-axis direction, thereby achieving stable cooling. If more than a certain percentage, for example more than half, of the cavity 14 located between the fixed mold 12 and the movable mold 13 is located in the movable mold 13, the cooling efficiency may decrease when two cooling liquid paths are provided in the fixed mold 12.

[0138] 12B-12D show views of mold A or mold B from the YZ plane. When the cavity 14 (not shown in FIG. 12B-12D) is more than a certain percentage in the fixed mold 12, two cooling liquid paths can be installed in the fixed mold 12 as shown in FIG. 12C and FIG. 12D. When the cavity 14 (not shown in FIG. 12C or FIG. 12D) is less than a certain percentage in the fixed mold 12, cooling liquid paths can be installed in the fixed mold 12 and the movable mold 13, respectively, as shown in FIG. 12B.

[0139] Cooling efficiency can be achieved with the size of the cavity 14 as well as the shape of the cavity 14. Depending on the shape of the cavity 14, the location of the two coolant paths can be determined so that the coolant paths can easily pass through the mold. If the shape of the coolant paths in the mold becomes complicated, the cost of the mold will increase proportionally. Therefore, the coolant paths do not pass through a mold that includes a complicated area of ​​the cavity 14, for example.

[0140] 13 shows the coolant paths when the molds A and B are placed on the cart 300, and the external piping attached / connected to the molds via their respective inputs / outputs. More specifically, FIG. 13 shows the XZ plane as seen from the injection molding machine cylinder 11 side. As seen from the mold B, the mold A is located in the positive direction of the X axis, and the actuator 18 is located in the negative direction of the X axis. When the mold A moves from the injection molding machine 200 in the positive direction of the X axis, and the mold B moves from the injection molding machine 200 in the negative direction of the X axis, both molds move to the outside of the injection molding machine 200.

[0141] When the molds are installed, as shown in Fig. 13, mold A uses coolant path 20 and mold B uses coolant path 21. When the positional relationship between mold A and mold B is reversed, mold A uses coolant path 21 and mold B uses coolant path 20.

[0142] For mold A, a pipe 600i that supplies liquid to the coolant channels 20 is connected to a liquid inlet 20i. A pipe 600o that allows liquid to exit the coolant channels 20 is connected to a liquid outlet 20o. For mold B, a pipe 600i is connected to a liquid inlet 21i, and a pipe 600o is connected to a liquid outlet 21o.

[0143] Furthermore, regardless of the positional relationship between mold A and mold B, the piping can be easily connected without the need to enter injection molding machine 200 when installing the molds. Since the piping does not pass between mold A and mold B and does not enter injection molding machine 200, it is possible to reduce the possibility of problems such as clogging or damage to the piping due to the piping being caught between the mold and other structures in injection molding machine 200. In the case of FIG. 13, coolant path 21 of mold A and coolant path 20 of mold B are not used and, as such, are not connected to external piping.

[0144] The use of conduits to supply electrical signals will now be described with reference to Figures 14A-14B and Figure 15. Figure 14A shows a similar perspective view of mould A or mould B as in Figure 12A. As in Figure 12A, the central region of the mould is shown to simplify the illustration of the resin moulded part 9.

[0145] Conduit connectors 22 and 23 facilitate the connection of external electrical wiring inside the mold via conduit 2223. Conduit connectors 22 and 23 may be located in different planes of the mold along the X-axis, each on opposite sides of the mold in the direction of mold movement. More specifically, conduit connectors 22 and 23 allow external electrical wiring to reach connector 24, which is connected to hot runner 2 via conduit 2223. Connector 24 is also connected to conduit 2223.

[0146] Connector 24 allows external electrical wiring to reach a controller (not shown) associated with hot runner 2. The external electrical wiring outside of the mold is connected to controller 70. Thus, control unit 70 (see FIG. 9 ) can control hot runner 2 via electrical wiring provided through conduit connectors 22, 23, conduits 22, 23, and connector 24.

[0147] The conduit 2223 and conduit connectors 22, 23 facilitate directing or controlling the hot runner 2, so that the conduit 2223, conductor 22, and conduit conductor 23 are disposed above the fixed mold 12 on which the hot runner 2 is disposed. Unlike separate coolant paths 20 and 21, the conduit 2223 is a single path that intersects at connector 24. Unlike the coolant paths, it is not necessary to ensure that the paths of the electrical wiring entering through the conduit connector 22 and the conduit connector 23 do not interfere with each other. Conversely, in some cases, it may be beneficial to share circuits, printed circuit boards (PCBs), or other electronic devices to simplify the paths of the electrical wiring associated with the conduit conductor 22 and the conduit 23, respectively.

[0148] FIG. 14B is a view of mold A or mold B from the YZ plane. The electrical wiring path associated with either conduit connector 22 or conduit connector 23 can be connected to connector 24 via conduit 2223 on the hot runner 2 side, regardless of the shape or size of cavity 14. In another exemplary embodiment, the electrical wiring path associated with conduit connector 22 or conduit connector 23 can be directly connected to a controller (not shown) associated with hot runner 2 via conduit 2223 without using connector 24. Hot runner 2 can be aligned in any direction. While hot runner 2 is aligned along the X-axis in FIG. 14A, hot runner 2 is aligned along the Z-axis in FIG. 14C.

[0149] FIG. 15 shows the structure of the electrical wiring connection when molds A and B are installed on cart 300 (not shown in FIG. 15). Conduit 700 can be arranged on the outside of injection molding machine 200 in two different planes for each mold in any direction. For example, the direction in which the molds exit injection molding machine 200. Connection of conduit 700 when installing additional molds can be easily accomplished regardless of the relative positions of molds A and B. Conduit 700 includes electrical wiring that is connected to control unit 70. In mold A, conduit 700 connects to conduit 2223 via conduit connector 22. In mold B, conduit 700 connects to conduit 2223 via conduit connector 23.

[0150] In another embodiment, two of each of the coolant and electrical wiring paths may be included in one mold. Operator ease of use is enhanced by providing the same layout of coolant and electrical wiring paths on any surface of the mold.

[0151] As described above, by arranging the piping and conduits for the mold and their associated connectors in the direction in which the mold exits the injection molding machine 200, it is possible to reduce potential clogging of the piping and conduits inside the injection molding machine 200 or damage to the piping or conduits. Since it is possible to connect external piping and / or external conduits to each of the two surfaces of the mold arranged in the direction of the mold movement, it is possible to install internal piping and / or internal conduits to exit the injection molding machine 200 regardless of the position of the mold. The above-mentioned liquid inlets (20i, 21i), liquid outlets (20o, 21o), and conduit connectors (22, 23) can be collectively referred to as "external connection parts (units)". The external connection parts allow the connection of equipment, units, etc. outside the injection molding machine and the operation of a predetermined process on the mold.

[0152] When a user wants to replace a mold at any position with another mold, if the mold located at one position has two sets of piping and two sets of conduits with the same function in two different planes, the user can easily replace the mold. Since the user does not need to worry about which mold can be located at any position, the user does not need to select another mold to be located at another position so that the two molds can be properly located. With two inlets / outlets for piping and conduits in different planes of the mold, the user can select any two mold combination, resulting in higher productivity.

[0153] For example, the mold at position A can be replaced from mold 1 to mold 2, the mold at position B can be replaced from mold 3 to mold 4, and then the mold at position A can be replaced from mold 2 to mold 3. Since the molds can be installed regardless of the position, only the work at the replacement position can be performed.

[0154] In the following, two different planes are described in which two sets of piping and conduits have the same function, such as inputting liquid for cooling the mold, outputting liquid used to cool the mold, and controlling the hot runner to communicate with the controller.

[0155] Figures 16A-16B show the connection element of this embodiment. Figure 16A shows the surface E1, which is the YZ plane of the mold A or mold B and is shown in Figures 12A, 14A, and 14C. Figure 16B shows the surface E2, which is the YZ plane of the mold A or B and is also shown in Figures 12A, 14A, and 14C. E1 and E2 are different planes of the YZ plane of the mold A or B, and are planes opposite each other.

[0156] Mold A or B includes a liquid inlet 20 in E1 and a liquid inlet 21i in E2, which are used to connect to external piping for inputting liquid as described above. Mold A or B also includes a liquid outlet 20o in E1 and a liquid outlet 21o in E2, which are used to connect to external piping for outputting liquid as described above. E1 and E2 also include conduit connectors 22 and 23. Thus, depending on the position of the mold, the user can choose to use either the external connection part (unit) on E1 or the external connection part on E2. Figures 16A to 16B show an example of an external connection part, where the external connection part can be located on either the fixed side mold 12 or the moving side mold 13.

[0157] The mechanisms for attaching the links 15 and 17 are also located in both the E1 and E2 planes. E1 includes the liquid flow connecting elements 20i, 20o and the conduit connecting element 22c, a mechanism for attaching the link 15, and a mechanism for attaching the link 17. E2 includes the liquid inlet 21i, the liquid outlet 21o, the conduit connecting element 23c, a mechanism for attaching the link 15, and a mechanism for attaching the link 17. The mechanism for attaching the link 15 and the mechanism for attaching the link 17 can be a single mechanism.

[0158] 18A-18B and 19A-19B, in another exemplary embodiment, two independent air pipes can be installed in the mold like coolant paths. One air inlet connectable to one air pipe can be installed on one side of the mold, and the other air inlet connectable to the other air pipe can be installed on the other side of the mold. The other side of the mold is opposite to the one side of the mold.

[0159] Fig. 8 is a flowchart showing an example of processing executed by the controller 70. Each step of the flowchart in Figs. 8A-8B will be described with reference to the respective states in Figs. 1-7 and 9-11. Note that in the following example, a case will be described in which molding operations are performed by alternating between mold A and mold B, for example, molding using mold A → molding using mold B → molding using mold A.

[0160] In S1, initial settings are performed. Here, for example, the operating conditions of the injection unit 201 and the clamping unit 58 are registered for each of the molds A and B. These include, for example, the amount of resin injected at one time, the temperature, the injection speed, the clamping force, and the initial value of the position of the second movable platen 55 relative to the tie bars 59. Even if the molds A and B are the same, these conditions may be different. When the mold A is used for the first molding operation, the conditions related to the mold A are automatically set as the operating conditions. Furthermore, heating of the injection molding machine cylinder 11, plasticization of the resin, measurement, and the like are started for the first time.

[0161] In S2, the mold A is transported into the injection molding machine 200. The motor 57 that slides the movable platen is driven so that the space between the fixed platen 53 and the first movable platen 54 becomes slightly wider than the thickness (width in the Y direction) of the mold A, thereby allowing the mold A to slide between the fixed platen 53 and the first movable platen 54. Next, the controller 70 controls the loading of the mold A and the driving of the actuator 18 to load the mold A into the injection molding operation position. When the loading is completed, a signal indicating the completion of loading is transmitted to the controller 70. When the signal indicating the completion of loading is received, the motor 57 is driven so that the fixed platen 53 and the first movable platen 54 are brought into close contact with the mold A. At this time, a clamping force is generated during molding, and is therefore unnecessary. Furthermore, the mold A is locked to both the fixed platen 53 and the first movable platen 54 by driving the fixing mechanism 60.

[0162] In S3, the mold A is clamped by the fixed platen 53 and the first movable platen 54 by driving the motor 57 to drive the toggle mechanism. The toggle mechanism is composed of multiple links that are rotatable relative to one another, and can change the distance between the first movable platen 54 and the second movable platen 55. This makes it possible to tightly clamp the mold.

[0163] In S4, preparations for injection into molds A and B are made. Here, actuator 57 is driven to move injection device 201 and bring injection molding machine nozzle 1 into contact with mold A. Actuator 57 is a drive source for moving the movable platen. Preparations for injection include bringing injection molding machine nozzle 1 into contact with the molds and moving valve pin 6 and sprue pin 7 to open the flow path of the resin.

[0164] In S5, the molten resin is injected and dwelled. The injection device 201 is driven to fill the cavity 14 in the mold A with the molten resin from the injection molding machine nozzle 1, and to push the resin in the injection molding machine cylinder 11 into the mold A at high pressure to compensate for the volume reduction caused by the resin solidification. The actual clamping force is measured by the sensor 68 through the process of S5. During molding, the temperature of the mold A gradually increases, so that the mold A thermally expands. In some cases, after a certain period of time has passed, a difference occurs between the initial clamping force and the clamping force. Therefore, the clamping force at the next clamping time can be corrected based on the measurement result by the sensor 68.

[0165] The clamping force is adjusted by adjusting the position of the second movable platen 55 relative to the tie bars 59 by driving the motor 55c. This makes it possible to adjust the clamping force and improve the accuracy of the clamping force by correcting the initial value of the position of the second movable platen 55 relative to the tie bars 59 based on the measurement result by the sensor 68. The adjustment of the position of the second movable platen 55 relative to the tie bars 59 can be performed at any timing.

[0166] In S6, the sprue pin 7 is moved to the injection molding machine nozzle 1 side to prevent resin from leaking from the sprue 4 side of the hot runner 2. The flow in the opening to the cavity 14 is stopped by the valve pin 6.

[0167] In S7, the molten resin present near the outlet of the injection molding machine nozzle 1 is pulled back. The screw 51 is retracted in the opposite direction of the injection molding machine nozzle 1 and sent backward. The resin present near the outlet of the injection molding machine nozzle 1 is returned to the inside of the injection molding machine nozzle 1.

[0168] In S8, the supply of resin to the injection molding machine nozzle 1 is stopped, and the injection molding machine nozzle 1 is closed by the shutoff nozzle 49.

[0169] In S9, the injection molding machine nozzle 1 starts to retreat. As shown in FIG. 5, the injection molding machine nozzle 1 is separated from the mold. At this time, since the sprue 4 is sealed with the sprue pin 7 in S6, the resin does not easily flow back. The injection molding machine nozzle 1 is sealed with the shutoff nozzle 49 before the injection molding machine nozzle 1 is separated, so that the resin does not easily leak from the injection molding machine nozzle 1. In addition, the pullback reduces the amount of resin present in the resin flow path of the injection molding machine nozzle 1, making it more difficult for the resin to leak from the injection molding machine nozzle 1. As a result, the resin does not accumulate between the injection molding machine nozzle 1 and the sprue 4, so that air does not easily enter the injection molding machine nozzle 1. In addition, even when molding is performed continuously, the possibility that a lump of resin gets caught between the parts of the injection molding machine 200 and the operation of the injection molding machine 200 stops is reduced.

[0170] Since less resin leaks from the injection molding machine nozzle 1, the injection molding machine nozzle 1 can be retracted at the same time as resin scaling, which will be described later in S12. Since no resin leaks from the injection molding machine nozzle 1 even when the injection molding machine nozzle 1 is retracted, resin scaling can be performed in parallel.

[0171] In S10, timing begins for the cooling time of the mold injected into cavity 14 in S5.

[0172] In S11, the injection molding conditions of the injection molding machine 200 change with the change of the mold. Specifically, the preset injection molding conditions are changed to the injection molding conditions of the mold to be injected from this point on. Since it is necessary to perform resin scaling that matches the injection molding conditions of the mold B (or mold A), in S16 described later, the mold A (or mold B) is transported outside the injection molding machine 200, the mold B (or mold A) is carried into the injection molding machine 200, and injection and pressure holding of the mold B (or mold A) are performed.

[0173] The injection molding conditions set in S1 or S11 include all processes from when the mold enters the injection molding machine 200 until when it exits, such as the amount of movement of the mold, the timing of movement, the timing of contact / separation of the injection molding machine nozzle 1, and the timing of pullback. Therefore, by controlling the process from when the injection molding machine nozzle 1 enters the mold until when it exits the mold as one set of processes, management becomes easier when any problem occurs.

[0174] If the nozzle retraction occurs before scaling in S12, which is performed after completion of S11, there is a possibility that resin leakage will occur from the injection molding machine nozzle 1 due to back pressure during scaling. As a result, resin accumulates between the injection molding machine nozzle 1 and the sprue 4. The back pressure refers to the pressure generated in the direction of the resin coming out from the tip side of the injection molding machine nozzle 1 when the injection molding machine nozzle 1 retracts. If the accumulated resin becomes large, it may be pinched between the internal parts of the injection molding machine 200. The resin scaling performed in S12 generally requires several seconds to more than 10 seconds, but this may vary depending on the size of the injection molding machine. Therefore, the injection molding conditions are changed in S11, where scaling is performed after the retraction of the injection molding machine nozzle 1. As a result, it is possible to reduce the possibility of the resin backflow from the sprue 4 due to the residual pressure in the hot runner 2 or resin leakage.

[0175] In S12, scaling of the resin is performed based on the injection molding conditions set in S11.

[0176] In S13, the retraction of the injection molding machine nozzle 1 is completed.

[0177] In S14, the fixing mechanism (clamp) 60 is released. As shown in Fig. 10, the fixing mechanism 60 is a mechanism that fixes the mold to the stationary platen 53 / first movable platen 54. In order to replace the mold, the fixing mechanism 60 that is fixed to the fixed plates 12a, 13a of the stationary platen 53 / first movable platen 54 is removed.

[0178] In S15, the first movable platen 54 moves slightly in a direction separating it from the fixed platen 53. As a result, it becomes possible to move the mold, which could not be moved in the Y-axis direction because it was clamped between the fixed platen 53 and the first movable platen 54. More specifically, it becomes possible for the mold to move in the X-axis direction without coming into contact with the fixed platen 53 and the first movable platen 54 and without generating friction.

[0179] In S16, the molds are exchanged. More specifically, one mold enters the injection molding machine 200, and the other mold exits the injection molding machine 200. Since the two molds are connected via the link unit 15, the molds can enter and exit the injection molding machine 200 simultaneously via the movement of the actuator 18.

[0180] Steps S11-12 and steps S13-16 are performed in parallel, improving manufacturing efficiency.

[0181] In S17, it is determined whether or not this is the first molding operation for the mold present in the injection molding machine 200. It is also possible to determine whether or not there is a molded part in the mold.

[0182] If it is the first molding operation, the process returns to S3, and steps S3 to S16 are executed for another mold. If it is the second or subsequent molding operation, the process proceeds to S18. If it is determined in S17 that the injection and pressure holding of the mold currently inside the injection molding machine 200 is the first molding operation after the current count has started, there is no resin molded part 9 inside the mold. Therefore, the process of removing the molded part, which will be described later, cannot be applied to S18-S22, so the process proceeds to S3.

[0183] In S18, it is determined whether the cooling of the mold inside the injection molding machine 200 is completed based on whether the cooling time started in S10 has reached a predetermined time. If the cooling is completed, the process proceeds to S19. If not, the process remains in S18 until the predetermined time is reached.

[0184] In S19, the stationary platen 53 and the first movable platen 54 are closed. The movement of the first movable platen 54 is as described above for S15.

[0185] In S20, the fixed platen 53 / first movable platen 54 and the fixed plates 12a, 13a of the mold are fixed by the clamps 60. As a result, the mold becomes less likely to move in the X-axis and Y-axis directions.

[0186] In S21, the movable mold 13 and the fixed mold 12 are opened relative to the first movable platen 54 and the fixed platen 53. This makes it possible to remove the resin molded part 9 located between the movable mold 13 and the fixed mold 12. The first movable platen 54 is moved away from the fixed platen 53 by driving the motor 57. The fixed mold 12 is fixed to the fixed platen 53 by the fixing mechanism 60, and the movable mold 13 is fixed to the first movable platen 54 by the fixing mechanism 60. This causes the movable mold 13 to move away from the fixed mold 12 against the magnetic force of the self-closing unit 301, and the molds are opened.

[0187] In S22, the resin molded part 9 that has become removable by opening the mold in S21 is removed. The molded parts remaining on the movable mold 13 side of the mold are removed and transported outside the injection molding machine 200. In one exemplary embodiment, removal of the molded parts can be accomplished using a robot assembly. The resin molded part 9 can be removed by an ejection mechanism (not shown) or by moving a vacuum head (not shown) to the position of the resin molded part 9 and applying a vacuum force.

[0188] In S23, it is determined whether the production of the resin molded parts has been completed. This determination is based on whether a predetermined time has passed or a predetermined number of parts have been produced. The criterion for making the determination may be the amount of resin used instead of the predetermined time or number of parts produced.

[0189] When assembly is performed after the plastic molded parts are manufactured, manufacturing only partial parts in large quantities can take up space in a manufacturing facility. In this scenario, the determination can be based on whether a quantity based on other assembly parts has been manufactured on the production line. If it is determined in S23 that the production quantity of the plastic molded parts is completed, the process of Figures 8A-8B ends. If not, the process proceeds to S24.

[0190] In S24, the first movable platen 54 that was opened in S21 is closed relative to the stationary platen 53. This closes the movable mold 13 and the stationary mold 12. Then, the process returns to S3.

[0191] Injection molding into two molds has been described above. In the above embodiment, blocking is performed by the sprue pin 7 in S7. This prevents air from entering the hot runner 2 even when the injection molding machine nozzle 1 is retracted without waiting for the resin to scale. As a result, the cycle time can be shortened.

[0192] Since the nozzle is blocked as described in S7 and S8, the injection molding machine nozzle 1 can be retracted and scaled at the same time without resin leaking from the injection molding machine nozzle 1 side.

[0193] The setting of the injection molding conditions for each mold described in S11 can be performed before the start of nozzle blocking in S8 and the retraction of the injection molding machine nozzle 1 in S9. In the above embodiment, the setting change of S11 was performed after the start of the retraction of the injection molding machine nozzle 1 in S9. Since the processes of S8 and S9 are processes related to the injection molding machine 200, it is not necessary to perform the process of S11 after the process of S9. However, when a mold having a different position of the nozzle contact area 25 is used, if the injection molding conditions are changed before S9, there is a possibility that the movement of the injection molding machine nozzle 1 in S9 cannot be matched to the mold. In these cases, it is better to change the injection molding conditions in S11 after the start of the retraction of the injection molding machine nozzle 1 in S9.

[0194] The process of S11 can be carried out before the pullback of S7. However, the amount and strength of the pullback differs depending on the mold. For this reason, if the injection molding conditions are changed before S7, the pullback that was in the mold in which injection was performed immediately before in S5 becomes impossible. This problem can be addressed by doing the following. Specifically, if a common pullback amount is set according to the larger pullback amount of two different molds, S11 can be carried out before S7. Also, since it takes time to process the setting change of S11, manufacturing efficiency can be improved by carrying out the setting change of S11 in parallel with other processes.

[0195] As shown in Fig. 8A, S11 is performed after the start of the cooling time timing of S10. Since the cooling time depends on the molding conditions of each mold, if they are set in the same way, the cooling time may be insufficient or the manufacturing efficiency may decrease. In another exemplary embodiment, S11 can be performed before S10 even if the cooling time for the two molds is the same or cooling is performed based on the mold with a longer cooling time.

[0196] In another exemplary embodiment, the process of changing the mold in S16 can occur after scaling of the resin in S12. The mold can be changed after scaling, but this can result in a longer cycle time than the actual cooling time required, since delaying the mold change until scaling can result in the mold change time exceeding the cooling time.

[0197] In the above embodiment, two molds are discussed, but the present invention is not limited thereto, and the above embodiment can be applied to three or more molds. In addition, in the above embodiment, the movement of the mold is in the X-axis direction relative to the injection molding machine 200 installed along the Y-axis direction, but the present invention is not limited thereto. For example, the movement in the Z-axis direction is possible, and the movement corresponding to drawing a circle passing through the injection position of the injection molding machine 200 is also applicable.

[0198] The position where cooling is performed is not limited to being located outside the injection molding machine 200. For example, in the case of a small mold that requires time for cooling but allows for faster resin injection, cooling can be performed at multiple positions. When three or more molds are injection molded, the molds can be moved outside the injection molding machine 200 based on the cooling time, so that it is possible to prioritize the movement of molds that have passed the cooling time to the injection molding machine 200.

[0199] When the platens are opened and closed, the mold must avoid contacting the platens to the extent that it creates frictional forces that can impede movement during mold movement. Thus, the amount of actual movement of the mold in the Y-axis is very small. However, the rollers can be installed to move in the Y-axis. Allowing the rollers to move in the Y-axis provides additional clamping force to the mold.

[0200] Opening and closing of the platen is performed with the mold on rollers 63. At this time, the mold moves slightly in the Y direction with the platen open or closed. If the size of rollers 63 in the Y direction is too short, the mold may fall off rollers 63 when the platen is in the open position, so the size of the rollers must be such that the mold remains on rollers 63 regardless of whether the platen is in the open or closed position.

[0201] In the above embodiment, rollers on the cart 300 are described, but in another exemplary embodiment, rollers can be added to the mold instead of the cart 300. By adding rollers to the mold, vibrations to the mold caused by steps between the rollers can be reduced. This can prevent the mold from shifting due to vibrations when manufacturing high-precision parts, and can increase the probability of producing molded parts with high precision. Also, damage to the rollers can be reduced.

[0202] As shown in Figure 10, clamps 60 are tightened with a strong force to achieve clamping when they enter their hole areas on fixed plates 12a and 13a. Repeated clamping will likely result in scraping and wear of the hole areas. In an exemplary embodiment, the hole portions of fixed plates 12a and 13a are designed to be replaceable to ensure that the entire mold does not have to be replaced if any portion of any hole becomes worn.

[0203] 10 of the above-described embodiment shows that the roller unit 61a is installed on the fixed platen 53 or the first movable platen 54, and the mold is moved within the XZ plane. At this time, if there is a hole on the mold side at a position where it contacts the roller unit 61a, the roller unit 61a may enter the hole and be damaged. In another exemplary embodiment, a hole is not provided at a position on the XZ plane of the mold, and the roller unit 61a is brought into contact with the roller unit 61a of the platen inside the injection molding machine 200, allowing the mold to move smoothly.

[0204] The part of the mold that contacts the roller unit 61a may be deformed by multiple mold movements. To address this, the hardness of the material of the part of the mold that contacts the rollers of the roller unit 61a can be lower than the hardness of the rollers, while the hardness of the reaming section of the mold is higher. The wear on the roller side is higher when the hardness of the mold is higher than the hardness of the rollers, so the hardness of the rollers needs to be higher. In another exemplary embodiment, the part of the mold that contacts the rollers is replaceable.

[0205] If the time required for all processes from the start of the mold change process to the other mold ejection process, injection process, and pressure holding process, and until the mold change process is completed again, is within the time required for cooling one of the molds, productivity will be doubled compared to normal molding. In other words, high productivity can be achieved while suppressing cost increases. This double productivity improvement can be achieved for a wide range of molded parts.

[0206] To achieve a two-fold increase in productivity, the cooling time of the mold can occupy more than 50% of the entire molding process (the time for one molding cycle), which depends on the time for the mold exchange process. Molded parts used in exterior parts and electromechanical parts of automobiles, home appliances, office equipment, etc. often have a thickness of several millimeters to ensure strength. Therefore, during the entire molding process, the cooling process takes the longest time, and it is not uncommon for the time to cool the mold to reach 50% to 70% in relation to the time of one molding cycle. Therefore, the above embodiment is particularly effective in improving the productivity of this type of molded part. In particular, if the time of the injection molding cycle of mold A and the time of the injection molding cycle of mold B are approximately the same, and the cooling time of the mold relative to the time of one molding cycle is 50% or more, the productivity can be improved.

[0207] Even if the time required to cool the mold is less than 50% of the time for one molding cycle, by effectively using the time for cooling, it is possible to achieve productivity that is 1.5 to 1.8 times higher than normal molding. According to the above embodiment, one injection molding machine 200 can achieve the productivity of two injection molding machines using conventional manufacturing methods, thereby reducing installation space and power consumption.

[0208] Moreover, in the above embodiment, a resin is used, but the material is not limited to this, and any material such as wax or metal can be used.

[0209] In another exemplary embodiment, the runners may be used without a heater or insulation for the mold.

Claims

1. In a mold in which a cavity for obtaining a molded product is formed, an injection port configured to inject molding material from a nozzle of an injection molding machine; a moving member that is provided in a flow path that guides the molding material injected from the injection port to the cavity, and that is configured to increase a flow rate of the molding material in the flow path by moving in a first direction along the flow path and to decrease a flow rate of the molding material in the flow path by moving in a second direction opposite to the first direction, The mold, wherein the movable member is configured to move by receiving a driving force from an actuator provided outside the mold.

2. The mold according to claim 1, characterized in that it has at least one of a first transmission path configured to transmit the driving force that moves the movable member in the first direction and a second transmission path configured to transmit the driving force that moves the movable member in the second direction.

3. The mold according to claim 1 or 2, characterized in that the flow path comprises a first flow path connected to the injection port and a second flow path having an inner diameter larger than that of the first flow path, and the size of the tip of the movable member in the second direction is the same as or smaller than the inner diameter of the first flow path and smaller than the inner diameter of the second flow path.

4. The mold according to claim 3, characterized in that when the movable member moves in the second direction, the movable member is stopped at a position where the tip portion enters the first flow path and the tip portion does not contact the nozzle.

5. The mold according to claim 4, characterized in that when the movable member moves in the second direction, the rear end of the movable member in the second direction is restricted, thereby stopping the movable member at the position.

6. an injection port configured to inject the molding material from the flow path into the cavity; a second moving member provided in the flow path and configured to open the ejection port by moving in the second direction and to close the ejection port by moving in the first direction, The mold according to claim 1 , wherein the second moving member is configured to move by receiving a driving force from the actuator provided outside the mold.

7. The mold according to claim 6, characterized in that it has at least one of a third transmission path configured to transmit the driving force that moves the second movable member in the first direction and a fourth transmission path configured to transmit the driving force that moves the movable member in the second direction.

8. The mold of claim 1 , further comprising a hot runner including a heater.

9. The mold according to claim 1 , wherein the molding material is a resin.

10. The mold according to any one of claims 1 to 9, wherein the mold is divided into a first mold and a second mold, the molding material is injected into the cavity when the first mold and the second mold are in contact, and the molded product is removed from the cavity when the first mold and the second mold are separated.

11. A mold having a cavity for obtaining a molded product; an injection molding machine for injecting a molding material into the mold; a conveying device configured to move the mold between a first position where the injection molding machine injects the molding material into the mold and a second position different from the first position; In an injection molding system having The mold includes an injection port configured to inject the molding material from a nozzle of the injection molding machine, and a moving member provided in a flow path that guides the molding material injected from the injection port to the cavity, the moving member being configured to increase a flow rate of the molding material in the flow path by moving in a first direction along the flow path and to decrease a flow rate of the molding material in the flow path by moving in a second direction opposite to the first direction, 11. An injection molding system comprising: an actuator configured to move the moving member in at least one of the first direction and the second direction.

12. 12. The injection molding system according to claim 11, wherein the mold includes at least one of a first transmission path configured to transmit a driving force from the actuator that moves the movable member in the first direction and a second transmission path configured to transmit a driving force from the actuator that moves the movable member in the second direction.

13. 13. The injection molding system according to claim 11 or 12, characterized in that the flow path comprises a first flow path connected to the injection port and a second flow path having an inner diameter larger than that of the first flow path, and the size of the tip of the moving member in the second direction is the same as or smaller than the inner diameter of the first flow path and smaller than the inner diameter of the second flow path.

14. 14. The injection molding system according to claim 13, wherein when the moving member moves in the second direction, the moving member is configured to stop at a position where the tip enters the first flow path and the tip does not contact the nozzle.

15. The injection molding system according to claim 14, characterized in that, when the movable member moves in the second direction, a rear end portion of the movable member in the second direction is restricted, so that the movable member is stopped at the position.

16. 16. The injection molding system according to claim 11, wherein the actuator moves the movable member in the first direction before injecting the molding material from the nozzle to the injection port, and moves the movable member in the second direction after injecting the molding material from the nozzle to the injection port and before the nozzle moves away from the injection port.

17. 17. The injection molding system according to claim 16, wherein the nozzle performs a suck-back to pull back the molding material after the actuator moves the moving member in the second direction and before the nozzle moves away from the injection port.

18. the mold has an injection port configured to inject the molding material from the flow path into the cavity, and a second movable member provided in the flow path and configured to open the injection port by moving in the second direction and close the injection port by moving in the first direction, 18. The injection molding system of claim 11, wherein the actuator is configured to move the second moving member in at least one of the first direction and the second direction.

19. 19. The injection molding system according to claim 18, wherein the actuator moves the second moving member in the second direction after moving the moving member in the first direction and before injecting the molding material from a nozzle of the injection molding machine to the injection port.

20. 20. The injection molding system of claim 11, wherein the actuator moves the moving member in the first direction after the transport device moves the mold from the second position to the first position, and moves the moving member in the second direction before the transport device moves the mold from the first position to the second position.

21. 21. The injection molding system of claim 11, wherein the first location is internal to the injection molding machine and the second location is external to the injection molding machine.

22. 22. The injection molding system according to claim 11, wherein the transport device is configured to move the two molds and transport the two molds alternately to the first position.

23. 23. The injection molding system of any one of claims 11 to 22, wherein the actuator is an air compressor, a servo motor or a hydraulic system.

24. 24. The injection molding system of claim 11, wherein the mold comprises a hot runner including a heater.

25. 25. The injection molding system according to claim 11, wherein the molding material is a resin.

26. The injection molding system according to any one of claims 11 to 25, wherein the mold is divided into a first mold and a second mold, the molding material is injected into the cavity when the first mold and the second mold are in contact, and the molded product formed in the cavity can be removed when the first mold and the second mold are separated.

27. A method for producing a molded product using the injection molding system according to any one of claims 11 to 26.

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