Molding machine

Abstract

To provide a molding machine that allows reduction of a waiting time before initiation of a subsequent molding cycle.SOLUTION: A molding machine comprises a mold clamping device that opens and closes and clamps a mold, an injection device that injects a molding material into a cavity of the clamped mold, an ejector device that separates a molded product from the opened mold, an input device to which an operator operation is input, and a control device that controls the mold clamping device and the injection device in accordance with the operator operation input to the input device. The ejector device includes an ejector pin movable between a retracted limit at which a tip end is immersed in the mold and an advanced limit at which the tip end protrudes from an inner surface of the mold. The control device executes, with the mold kept opened, an advance process of advancing the ejector pin, and a retreat process of retreating the ejector pin from a current position when a retreat instruction operation instructing retreat of the ejector pin is input to the input device before the advancing ejector pin reaches the advanced limit.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a molding machine equipped with an ejector device. [Background technology]

[0002] Conventionally, molding machines have been known that include a mold clamping device that opens, closes, and clamps a mold, an injection device that injects molding material into the cavity of the clamped mold, and an ejector pin that ejects a molded product from the open mold (see, for example, Patent Documents 1 to 3).

[0003] Furthermore, the molding machines described in Patent Documents 1 and 2 are equipped with a so-called "semi-automatic mode" in which the next molding cycle starts when an operator, after removing the molded product that has been separated from the mold by the ejector pin and confirming its quality, gives an instruction to mold the next molded product. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-074130 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-112752 [Patent Document 3] Japanese Patent Application Laid-Open No. 2009-274356 Summary of the Invention [Problem to be solved by the invention]

[0005] When the molding machine having the above configuration is operated in semi-automatic mode, there is a possibility that an operator will remove the molded product before the ejector pins reach their forward limit. However, even in such a case, if the ejector pins are moved to their forward limit, there is a problem that the waiting time until the start of the next molding cycle will be long.

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a molding machine that can shorten the waiting time until the next molding cycle starts. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides a molding machine comprising a mold clamping device that opens and closes a mold and clamps it, an injection device that injects molding material into a cavity of the clamped mold, an ejector device that separates a molded product from the open mold, an input device into which operations by an operator are input, and a control device that controls the mold clamping device and the injection device in accordance with the operator's operations input to the input device, wherein the ejector device has ejector pins that are movable between a rearward limit where their tips are recessed into the mold and an forward limit where their tips protrude from the inner surface of the mold, and the control device executes an advancement process that advances the ejector pins while the mold is open, and a retraction process that retracts the ejector pins from their current positions when a retraction command operation to retract the ejector pins is input to the input device before the advancing ejector pins reach the forward limit. [Effects of the Invention]

[0008] According to the present invention, the waiting time until the start of the next molding cycle can be reduced. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of an injection molding machine. [Figure 2] 10A and 10B are diagrams for explaining the operation of the ejector device. [Figure 3] FIG. 2 is a hardware configuration diagram of an injection molding machine. [Figure 4] FIG. 3 is a process diagram of an injection control process according to the first embodiment. [Figure 5] 4 is a flowchart of an ejector pin advance / retract process according to the first embodiment. [Figure 6]FIG. 10 is a process diagram of an injection control process according to a second embodiment. [Figure 7] 10 is a flowchart of an ejector pin advance / retract process according to the second embodiment. [Figure 8] FIG. 11 is a process diagram of an injection control process according to the third embodiment. [Figure 9] 11 is a flowchart of an ejector pin advance / retract process according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] An injection molding machine 10 according to the present invention will be described below with reference to the drawings. The injection molding machine 10 is a device that injects a measured amount of plasticized resin (molding material) into a mold to form a molded product M (hereinafter referred to as "injection molding"). However, a specific example of the molding machine is not limited to the injection molding machine 10, and may be a die-casting machine that injects molten metal (molding material) into a mold to form the molded product M.

[0011] [Configuration of injection molding machine 10] Fig. 1 is a side view of the injection molding machine 10. Fig. 2 is a diagram for explaining the operation of the ejector device 40. Fig. 3 is a hardware configuration diagram of the injection molding machine 10. As shown in Figs. 1 to 3, the injection molding machine 10 mainly includes a mold clamping device 20, an injection device 30, an ejector device 40, and a control device 60.

[0012] The mold clamping device 20 opens, closes, and clamps the mold 21. Specifically, the mold clamping device 20 mainly includes a fixed die plate 23 that supports a fixed-side mold 22, and a movable die plate 25 that supports a movable-side mold 24. The fixed-side mold 22 and the movable-side mold 24 are supported so as to face each other in the left-right direction (horizontal direction) of the injection molding machine 10.

[0013] The movable die plate 25 moves left and right along the tie bars 27 as the driving force of the die opening / closing motor 28 is transmitted through the toggle link mechanism 26. When the movable die plate 25 moves leftward, the fixed-side die 22 and the movable-side die 24 move apart. On the other hand, when the movable die plate 25 moves rightward, the fixed-side die 22 and the movable-side die 24 come into contact with each other, forming a cavity C (internal space) inside the die 21. Then, when pressure is further applied in a direction that moves the movable die plate 25 rightward, the fixed-side die 22 and the movable-side die 24 are clamped together.

[0014] The injection unit 30 plasticizes, measures, and injects the molding material. The injection unit 30 according to this embodiment is disposed facing the mold clamping unit 20 in the horizontal direction (to the right of the mold clamping unit 20). The injection unit 30 mainly includes a heating cylinder 31, a screw 32, a hopper 33, and a hopper block 34.

[0015] The heating cylinder 31 is a cylindrical member extending in the left-right direction of the injection molding machine 10. The heating cylinder 31 mainly includes a resin passage 35 and a nozzle 36. A band heater (not shown) for heating the heating cylinder 31 is attached to the outer circumferential surface of the heating cylinder 31.

[0016] The resin passage 35 is a cylindrical space extending in the axial direction (longitudinal direction) inside the heating cylinder 31. The resin passage 35 communicates with the outside of the heating cylinder 31 (cavity C of the mold 21) through a nozzle 36 provided at the tip (front end) of the heating cylinder 31. In other words, the resin passage 35 is a space extending from the nozzle 36 along the axial direction.

[0017] The screw 32 is a cylindrical member. A groove extending spirally along the longitudinal direction of the screw 32 is formed on the outer circumferential surface of the screw 32. The screw 32 is housed in the internal space of the heating cylinder 31 in a state in which it can move in the left-right direction of the injection molding machine 10 (hereinafter referred to as "forward and backward") and rotate. Furthermore, the screw 32 in the heating cylinder 31 is configured to be replaceable.

[0018] The screw 32 advances and retreats when the driving force of the injection motor 37 is transmitted thereto, and rotates when the driving force of the metering motor 38 is transmitted thereto. More specifically, when the injection motor 37 is rotated forward, the screw 32 moves (advances) toward the tip end of the heating cylinder 31 (i.e., the nozzle 36). On the other hand, when the injection motor 37 is rotated reversely, the screw 32 moves (retreats) toward the base end of the heating cylinder 31 (i.e., the side opposite the nozzle 36).

[0019] Hereinafter, within the range that the tip position of the screw 32 can reach within the heating cylinder 31, the position closest to the nozzle 36 will be referred to as the "forward limit," and the position farthest from the nozzle 36 will be referred to as the "rear limit." Furthermore, the terms "forward rotation" and "reverse rotation" of the injection motor 37 do not specify an absolute direction of rotation, but merely specify a relative relationship (i.e., forward rotation and reverse rotation are rotations in opposite directions).

[0020] The hopper 33 is a funnel-shaped member that stores granular resin as a raw material. The hopper block 34 is a member that supports the heating cylinder 31 and the hopper 33. The hopper 33 is connected to a resin passage 35 through the hopper block 34 on the base end side of the tip of the heating cylinder 31. The granular resin stored in the hopper 33 is supplied to the resin passage 35 of the heating cylinder 31 through an opening provided at the bottom end. The granular resin used in this injection molding machine 10 is, for example, so-called "pellets (granular resin)" molded into a cylindrical (granular) shape.

[0021] In the injection device 30, the screw 32 moves backward while rotating by rotating the injection motor 37 in the reverse direction and rotating the metering motor 38. As a result, pellets supplied through the hopper 33 are plasticized and filled (metered) into the resin passage 35 ahead of the screw 32. In addition, in the injection device 30, the injection motor 37 rotates forward to move the screw 32 forward. As a result, the plasticized resin ahead of the screw 32 is injected into the cavity C of the mold 21 through the nozzle 36.

[0022] The ejector device 40 is a device that separates the molded product M from the open mold 21. The ejector device 40 is supported by, for example, the movable die plate 25 and moves together with the movable die plate 25. The ejector device 40 mainly includes an ejector pin 41 and an ejector motor 42. Although only one ejector pin 41 is shown in FIGS. 1 and 2, there may be multiple ejector pins 41.

[0023] The ejector pins 41 separate the molded article M from the inner surface of the movable mold 24 by appearing and disappearing from the inner surface (surface defining the cavity C) of the movable mold 24. The ejector pins 41 move back and forth between a retraction limit shown in FIGS. 2(A) and 2(B) and an advance limit shown in FIG. 2(C). The retraction limit is the position of the ejector pin 41 where the tip (the end that can come into contact with the molded article M) is retracted into the movable mold 24. The advance limit is the position of the ejector pin 41 where the tip protrudes from the inner surface of the movable mold 24 and separates the molded article M from the movable mold 24.

[0024] The ejector motor 42 generates a driving force that moves the ejector pins 41 forward and backward. When the ejector motor 42 is rotated forward, the ejector pins 41 move from the backward limit side to the forward limit side (hereinafter referred to as "forward"). On the other hand, when the ejector motor 42 is rotated backward, the ejector pins 41 move from the forward limit side to the backward limit side (hereinafter referred to as "rearward"). Note that the "forward rotation" and "reverse rotation" of the ejector motor 42 merely specify a relative relationship, similar to the injection motor 37.

[0025] As shown in Fig. 2(A), when the mold 21 is closed and clamped, the ejector pins 41 are positioned at their rearmost position. This causes the cavity C to assume a shape corresponding to the molded article M. On the other hand, when the molded article M is molded in the cavity C and the mold 21 is opened, the ejector pins 41 become able to advance, as shown in Fig. 2(B). Then, when the ejector pins 41 advance, the molded article M separates from the inner surface of the movable mold 24 (i.e., the cavity C), as shown in Fig. 2(C).

[0026] Furthermore, as shown in FIG. 1, the injection molding machine 10 is equipped with a door 11. The door 11 is disposed at a position facing the mold 21 in the front-to-rear direction. The door 11 is configured to be movable (for example, pivotable or slidable) between a closed position and an open position by an operator. The closed position is a position of the door 11 that closes the position facing the open mold 21 (in other words, makes it impossible to remove the molded article M that has been separated from the mold 21 by the ejector device 40). The open position is a position of the door 11 that opens the position facing the open mold 21 (in other words, makes it possible to remove the molded article M that has been separated from the mold 21 by the ejector device 40).

[0027] [Configuration of control device 60] As shown in Fig. 3, the control device 60 includes a CPU (Central Processing Unit) 61 and a memory 62. The memory 62 is configured, for example, with a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), or a combination of these. The control device 60 realizes the processing described below by having the CPU 61 read and execute program code stored in the ROM or HDD. The RAM is used as a work area when the CPU 61 executes the program.

[0028] However, the specific configuration of the control device 60 is not limited to this, and may be realized by hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array).

[0029] The control device 60 controls the overall operation of the injection molding machine 10. More specifically, the control device 60 controls the mold opening / closing motor 28, the injection motor 37, the metering motor 38, the ejector motor 42, and the locking mechanism 68 based on various signals output from a door sensor 63, rotary encoders 64 and 65, a load cell 66 (pressure sensor), and a display / input device 67.

[0030] The mold opening / closing motor 28, injection motor 37, metering motor 38, and ejector motor 42 are servo motors that generate driving forces to open and close the mold 21, driving forces to move the screw 32 back and forth, driving forces to rotate the screw 32, and driving forces to move the ejector pin 41 back and forth, for example, under the control of a servo amplifier (not shown).

[0031] The door sensor 63 detects whether the door 11 is in the closed position and outputs a detection signal indicating the detection result to the control device 60. More specifically, the door sensor 63 outputs a detection signal when the door 11 is in the closed position and stops outputting the detection signal when the door 11 is in a position other than the closed position. As the door sensor 63, for example, a well-known sensor such as an optical sensor, a proximity sensor, or a contact sensor can be used.

[0032] The rotary encoder 64 is a sensor that detects the speed and tip position of the screw 32. More specifically, the rotary encoder 64 outputs pulse signals corresponding to the rotation of the injection motor 37 to the control device 60. The control device 60 then determines the speed of the screw 32 based on the number of pulse signals output per unit time. The control device 60 also determines the tip position of the screw 32 based on the cumulative value of the pulse signals.

[0033] The rotary encoder 65 is a sensor that detects the tip position of the ejector pin 41. More specifically, the rotary encoder 65 outputs a pulse signal corresponding to the rotation of the ejector motor 42 to the control device 60. Then, the control device 60 identifies the tip position of the ejector pin 41 based on the cumulative value of the pulse signal output from the rotary encoder 65.

[0034] The load cell 66 is a pressure sensor that detects the pressure (back pressure) applied to the screw 32. More specifically, the load cell 66 outputs a pressure signal (voltage value) corresponding to the pressure applied to the screw 32 to the control device 60. Then, the control device 60 identifies the pressure applied to the screw 32 based on the pressure signal output from the load cell 66.

[0035] The display input device 67 is a user interface that includes a display (display device, notification device) that displays various information to be notified to the operator, and buttons, switches, dials, etc. (input devices) that accept input operations by the operator. The display input device 67 may include a touch panel superimposed on the display. The display input device 67 accepts input operations by the operator and outputs an input signal corresponding to the accepted input operation to the control device 60.

[0036] The locking mechanism 68 is a mechanism that locks the door 11 in a closed position under the control of the control device 60. When the locking mechanism 68 locks the door 11 (hereinafter referred to as "door lock ON"), the operator cannot move the door 11 from the closed position. On the other hand, when the locking mechanism 68 unlocks the door 11 (hereinafter referred to as "door lock OFF"), the operator can move the door 11 between the closed position and the open position. The specific configuration of the locking mechanism 68 is not particularly limited, but for example, an electromagnetic lock using an electromagnet can be adopted.

[0037] [Injection control process according to the first embodiment] 4 is a process diagram of the injection control process according to the first embodiment. The injection control process is a process in which plasticized resin filled in the heating cylinder 31 is injected into the cavity of the clamped mold 21 to form a molded product M. The injection control process in this specification is a so-called "semi-automatic mode" process in which an operator removes the molded product M separated from the mold 21 by the ejector device 40, checks its quality, and then issues an instruction to mold the next molded product M.

[0038] At the start of the injection control process, the mold 21 is opened, the plasticized resin to be injected next is measured into the space ahead of the screw 32 of the heating cylinder 31, the door 11 is in the closed position, the locking mechanism 68 is in the door lock ON state, and the ejector pin 41 is in the rearmost position.

[0039] First, the control device 60 closes and clamps the mold 21 by rotating the mold opening / closing motor 28. As a result, a cavity is formed in the mold 21. This process is an example of a mold clamping process.

[0040] Next, after the mold clamping process is completed, the control device 60 rotates the injection motor 37 in the forward direction to move the screw 32 forward. As a result, the plasticized resin measured in the region in front of the screw 32 in the heating cylinder 31 is injected into the cavity of the mold 21. This process is an example of an injection process.

[0041] Next, after the injection process is completed, the control device 60 supplies power to the injection motor 37 so that the screw 32 presses the molding material at a predetermined target pressure. This applies pressure to the molded product M in the cavity C. As a result, the plasticized resin is filled into the cavity C without any gaps, preventing molding defects. This process is an example of a pressure holding process.

[0042] Next, after the pressure-holding process is completed, the control device 60 rotates and moves the screw 32 backward, thereby plasticizing the granular resin supplied to the heating cylinder 31 through the hopper 33, and measuring the plasticized resin to be injected next into the space ahead of the screw 32 of the heating cylinder 31. This process is an example of a measuring process.

[0043] Furthermore, after the dwelling process is completed, the control device 60 cools the plasticized resin in the cavity C in parallel with the weighing process. As a result, the plasticized resin is cooled in the mold 21, and the molded product M is formed. At this time, the control device 60 may circulate cooling water through a cooling water channel provided in the mold 21. This process is an example of a cooling process. The weighing process and the cooling process may be completed simultaneously, or one of them (the weighing process in the example of FIG. 4) may be completed first.

[0044] Next, after both the measurement process and the cooling process are completed, the control device 60 rotates the mold opening / closing motor 28 to open the mold 21. This allows the ejector pins 41 to move forward, as shown in FIG. 2(B). At this point, the molded product is assumed to be supported by the movable mold 24. This process is an example of a mold opening process.

[0045] Next, after the mold opening process is completed, the control device 60 rotates the ejector motor 42 in the forward direction to move the ejector pins 41 forward. As a result, as shown in FIG. 2(C), the molded article M pushed out at the tip of the ejector pins 41 moves away from the inner surface of the movable mold 24. This process is an example of an advance process (EJ advance). In addition, the control device 60 causes the locking mechanism 68 to unlock the door 11 at the same time as the advance process starts. This allows the operator to move the door 11 to the open position and remove the molded article M pushed out by the ejector pins 41.

[0046] Next, after the forward movement process is completed, the control device 60 reversely rotates the ejector motor 42 to move the ejector pins 41 backward. This makes it possible to close and clamp the mold 21. This process is an example of a backward movement process (EJ backward movement). Furthermore, the control device 60 causes the locking mechanism 68 to lock the door 11 in the closed position at the start of the backward movement process. That is, in the first embodiment, the door 11 needs to be in the closed position at the start of the backward movement process.

[0047] The series of processes including the mold clamping process, injection process, pressure holding process, metering process, cooling process, mold opening process, forward movement process, and backward movement process described above is a set of processes required to mold the molded product M, and will be referred to as a "molding cycle" hereinafter. The time required to execute one molding cycle will be referred to as a "cycle time." The starting position of the molding cycle can be any position, such as the mold clamping process or backward movement process.

[0048] After removing the molded product M and checking its quality, the operator changes the molding conditions as necessary and presses the "next cycle start key" on the display / input device 67. This starts the molding of the next molded product M (i.e., the next molding cycle). The next cycle start key may take any form, such as a push button or an icon displayed on a display. The same applies to the other keys described below. Pressing the next cycle start key is an example of a retraction instruction operation that instructs the ejector pins 41 to retract, and is also an example of a molding instruction operation that instructs the molding of the next molded product M.

[0049] [Ejector pin advance / retract process according to the first embodiment] Here, the operator can move the door 11 to the open position at any timing during the forward movement process to remove the molded article M. In other words, the operator can remove the molded article M before the ejector pins 41 reach their forward limit. However, as shown in Fig. 4(A), if the backward movement process cannot be started until the ejector pins 41 reach their forward limit, there is a problem that the waiting time (≒ cycle time) until the start of the next molding cycle becomes long.

[0050] Therefore, the control device 60 according to the first embodiment executes the ejector pin advance / retract process shown in Fig. 5. Fig. 5 is a flowchart of the ejector pin advance / retract process according to the first embodiment. The ejector pin advance / retract process is a process from the start of the forward movement process to the start of the backward movement process.

[0051] First, the control device 60 rotates the ejector motor 42 in the forward direction and causes the locking mechanism 68 to unlock the door 11 (S11). This causes the ejector pin 41 to start moving forward, and the door 11 becomes openable. The control device 60 then continues to rotate the ejector motor 42 in the forward direction until the ejector pin 41 reaches its forward limit (S12: No) or until the next cycle start key is pressed with the door 11 closed (S17: No / S18: No).

[0052] Next, the control device 60 stops the ejector motor 42 (S13) in response to the ejector pin 41 reaching its forward limit (S12: Yes). However, at this point, the door 11 remains unlocked by the locking mechanism 68. That is, the operator opens the door 11 and removes the molded product M at any time after the forward movement process has started. The operator also checks the quality of the molded product M and changes the molding conditions as necessary. The operator then closes the door 11 and presses the next cycle start key.

[0053] Next, in response to the next cycle start key being pressed after the ejector pin 41 has reached its forward limit (S12: Yes & S14: Yes), the control device 60 determines whether the door 11 is in the closed position (S15). Then, in response to the determination that the door 11 is not in the closed position at the time the next cycle start key is pressed (S14: Yes & S15: No), the control device 60 waits without proceeding to the processing of step S16 and subsequent steps.

[0054] On the other hand, when the control device 60 determines that the door 11 is in the closed position at the time the next cycle start key is pressed (S14: Yes & S15: Yes), it causes the ejector motor 42 to rotate in reverse and causes the locking mechanism 68 to lock the door 11 in the closed position (S16). This causes the ejector pins 41 to move backward from their forward limit (i.e., transition to backward processing). On the other hand, the operator cannot open the door 11 while the ejector pins 41 are moving backward.

[0055] 4(A), the control device 60 sequentially executes mold clamping processing, injection processing, ..., and forward movement processing in response to the ejector pin 41 reaching its backward movement limit. The processing after the next cycle start key is pressed (in the first embodiment, the backward movement processing to the forward movement processing) is an example of the next molding cycle.

[0056] In response to this, the control device 60 determines whether the door 11 is in the closed position (S18) in response to the next cycle start key being pressed before the ejector pin 41 reaches its forward limit (S12: No & S17: Yes). Then, in response to the determination that the door 11 is not in the closed position at the time the next cycle start key is pressed (S17: Yes & S18: No), the control device 60 does not proceed to the processing of step S16 and onward, and continues the forward rotation of the ejector motor 42.

[0057] On the other hand, when the control device 60 determines that the door 11 is in the closed position at the time the next cycle start key is pressed (S17: Yes & S18: Yes), it executes the process of step S16 (i.e., proceeds to the retraction process). That is, the control device 60 retracts the ejector pin 41 from the current position (a position between the retraction limit and the forward limit) as shown in FIG. 4(B). The other processes of step S16 and the subsequent processes are the same as those described above.

[0058] [Effects of the first embodiment] According to the first embodiment, the retraction process is started without waiting for the ejector pins 41 to reach their forward limit, thereby reducing the time required for the ejector pins 41 to advance from their current positions to their forward limit and for the ejector pins 41 to retract from their forward limit to their current positions. As a result, the waiting time until the start of the next molding cycle can be reduced.

[0059] Furthermore, according to the first embodiment, by unlocking the door 11 by the locking mechanism 68 at the start of the forward movement process, the operator can remove the molded article M at any timing while the ejector pins 41 are moving forward. As a result, the earlier the operator removes the molded article M, the shorter the waiting time until the start of the next molding cycle.

[0060] Furthermore, according to the first embodiment, the process automatically shifts to mold clamping processing in response to the ejector pin 41 reaching its retreat limit, thereby reducing the operational burden on the operator.

[0061] [Second embodiment] The injection control process and the ejector pin advance / retract process according to the second embodiment will be described with reference to Figures 6 and 7. Figure 6 is a process chart of the injection control process according to the second embodiment. Figure 7 is a flowchart of the ejector pin advance / retract process according to the second embodiment. Note that a detailed description of the points in common with the first embodiment will be omitted, and the description will focus on the points of difference.

[0062] The second embodiment differs from the first embodiment in that it is assumed that the operator inserts an insert part into the open mold 21 before starting the next molding cycle (in the second embodiment, the mold clamping process). Therefore, the control device 60 has the operator press the "automatic retraction key" and the "next cycle start key" of the display input device 67 at different times during the molding cycle. Pressing the automatic retraction key is an example of a retraction instruction operation that instructs the ejector pins 41 to retract. Pressing the next cycle start key is an example of a molding instruction operation that instructs the molding of the next molded product M.

[0063] As shown in Fig. 6(A), after the ejector pins 41 reach their forward limit (S12: Yes), the control device 60 according to the second embodiment transitions to a retreat process (S16) in response to the automatic retreat key being pressed with the door 11 in the closed position (S24: Yes & S15: Yes). Similarly, as shown in Fig. 6(B), before the ejector pins 41 reach their forward limit (S12: No), the control device 60 according to the second embodiment transitions to a retreat process (S16) in response to the automatic retreat key being pressed with the door 11 in the closed position (S27: Yes & S18: Yes). That is, the operator may open the door 11 at any timing after the forward movement process (Fig. 6(A)) or during the forward movement process (Fig. 6(B)), remove the molded product M, close the door 11 again, and press the automatic retreat key.

[0064] 6, the control device 60 according to the second embodiment stops the ejector motor 42 and causes the locking mechanism 68 to unlock the door 11 in response to the ejector pins 41 reaching their rearward limit. This allows the operator to open the door 11 and insert an insert part into the mold 21. Furthermore, after the ejector pins 41 reach their rearward limit (i.e., after the rearward movement process is completed), the control device 60 according to the second embodiment starts the next molding cycle (mold clamping process in the second embodiment) and causes the locking mechanism 68 to lock the door 11 in the closed position in response to the next cycle start key being pressed with the door 11 in the closed position.

[0065] [Effects of the second embodiment] According to the second embodiment, it is possible to obtain the same effects as in the first embodiment, and by assigning the retraction instruction operation and the molding instruction operation to different keys, it is also possible to accommodate the insertion of insert parts.

[0066] [Third embodiment] The injection control process and the ejector pin advance / retract process according to the third embodiment will be described with reference to Figures 8 and 9. Figure 8 is a process chart of the injection control process according to the third embodiment. Figure 9 is a flowchart of the ejector pin advance / retract process according to the third embodiment. Note that a detailed description of the points in common with the first and second embodiments will be omitted, and the description will focus on the points of difference.

[0067] The third embodiment differs from the first embodiment in that it is assumed that the operator inserts an insert part into the open mold 21 before starting the next molding cycle (in the third embodiment, the mold clamping process). Therefore, the control device 60 has the operator press the "manual retract key" and the "next cycle start key" of the display input device 67 at different times during the molding cycle. Pressing the manual retract key is an example of a retract instruction operation that instructs the ejector pins 41 to retract. Pressing the next cycle start key is an example of a molding instruction operation that instructs the molding of the next molded product M.

[0068] The manual reverse key of the third embodiment is common to the automatic reverse key of the second embodiment in that it is a reverse instruction operation. On the other hand, the manual reverse key differs from the automatic reverse key, which automatically retracts the ejector pins 41 to the reverse limit when pressed (operated) once, in that the ejector motor 42 rotates in reverse (i.e., the ejector pins 41 retract) only while the manual reverse key is continuously pressed (operated), and the ejector motor 42 stops (i.e., the ejector pins 41 stop) when the manual reverse key is stopped (operated).

[0069] The manual reverse keys are disposed in two locations separated by a predetermined distance on the display / input device 67. The control device 60 retracts the ejector pin 41 only while the manual reverse keys disposed in two locations are pressed simultaneously (simultaneous operation). The "predetermined distance" at which the manual reverse keys are disposed is set to a distance at which the operator cannot operate them with one hand (in other words, both hands are required to operate them simultaneously).

[0070] As shown in Fig. 8(A), the control device 60 according to the third embodiment transitions to a retreat process (S16) after the ejector pins 41 reach their forward limit (S12: Yes) and in response to pressing of the manual retreat key (S34: Yes), regardless of the position of the door 11. Similarly, as shown in Fig. 8(B), the control device 60 according to the third embodiment transitions to a retreat process (S16) in response to pressing of the automatic retreat key (S37: Yes), regardless of the position of the door 11, before the ejector pins 41 reach their forward limit (S12: No). That is, the operator may open the door 11 at any timing after the forward movement process (Fig. 6(A)) or during the forward movement process (Fig. 6(B)), remove the molded product M, and then press the manual retreat key without closing the door 11.

[0071] 6, when the ejector pins 41 reach their rearward limit, the operator can release the manual rearward key and insert the insert part into the mold 21. Furthermore, after the ejector pins 41 reach their rearward limit (i.e., after the rearward process is completed), when the next cycle start key is pressed with the door 11 in the closed position, the control device 60 according to the third embodiment starts the next molding cycle (mold clamping process in the third embodiment) and causes the locking mechanism 68 to lock the door 11 in the closed position.

[0072] [Effects of the third embodiment] According to the third embodiment, the same effects as those of the second embodiment can be obtained, and by retracting the ejector pins 41 with the manual retraction key, it is no longer necessary to close the door 11 between the operation of removing the molded product M and the operation of inserting the insert part, which further reduces the waiting time until the start of the next molding cycle.

[0073] Furthermore, according to the third embodiment, by pressing the manual retraction key with both hands, it is possible to prevent the operator from accidentally inserting his / her hands between the molds 21 while the ejector pins 41 are retracting.

[0074] The above-described embodiments are merely illustrative examples of the present invention, and are not intended to limit the scope of the present invention to these embodiments. Those skilled in the art can implement the present invention in various other forms without departing from the spirit of the present invention. [Explanation of symbols]

[0075] 10... injection molding machine, 11... door, 20... mold clamping device, 21... mold, 22... fixed side mold, 23... fixed die plate, 24... movable side mold, 25... movable die plate, 26... toggle link mechanism, 27... tie bar, 28... mold opening / closing motor, 30... injection device, 31... heating cylinder, 32... screw, 33... hopper, 34... hopper block, 35... resin passage, 36... nozzle, 37... injection motor, 38... metering motor, 39... connecting pipe, 40... ejector device, 41... ejector pin, 42... ejector motor, 60... control device, 61... CPU, 62... memory, 63... door sensor, 64, 65... rotary encoder, 66... ​​load cell, 67... display input device, 68... locking mechanism

Claims

1. a mold clamping device that opens, closes, and clamps the mold; an injection device that injects a molding material into the cavity of the clamped mold; an ejector device that separates a molded product from the mold that has been opened; an input device into which an operation by an operator is input; a control device that controls the mold clamping device and the injection device in accordance with an operation of an operator input to the input device, the ejector device includes an ejector pin that is movable between a retreat limit where a tip thereof is retracted into the mold and an advance limit where a tip thereof protrudes from an inner surface of the mold, The control device an advancement process of advancing the ejector pin while the mold is open; and when a retraction instruction operation to retract the ejector pin is input to the input device before the advancing ejector pin reaches the advance limit, a retraction process is executed to retract the ejector pin from its current position.

2. The molding machine according to claim 1, a door that is movable between a closing position that closes a position facing the opened mold and an opening position that opens the position; a locking mechanism for locking the door in the closed position; a door sensor that detects when the door is in the closed position, The control device In the forward movement process, the locking mechanism is caused to unlock the door; a molding machine that transitions to the retraction process when the door sensor detects that the door is in the closed position and the retraction instruction operation is input.

3. The molding machine according to claim 2, The control device In the reverse process, the locking mechanism locks the door in the closed position, a molding machine that causes the mold clamping device and the injection device to mold the next molded product in response to the ejector pin reaching the retraction limit.

4. The molding machine according to claim 2, The control device In the reverse process, the locking mechanism locks the door in the closed position, causing the locking mechanism to unlock the door in response to the ejector pin reaching the rearward limit; a molding machine that, when the door sensor detects that the door is in the closed position and a molding instruction operation to mold the next molded product is input to the input device, causes the mold clamping device and the injection device to mold the next molded product.

5. The molding machine according to claim 1, a door that is movable between a closing position that closes a position facing the opened mold and an opening position that opens the position; a locking mechanism for locking the door in the closed position; a door sensor that detects when the door is in the closed position, The control device during the forward movement process and the reverse movement process, the locking mechanism is caused to unlock the door; a molding machine that causes the mold clamping device and the injection device to mold the next molded product when a molding instruction operation to mold the next molded product is input to the input device while the door sensor detects that the ejector pin is at the rearmost position and the door is at the closed position.

6. The molding machine according to claim 5, The molding machine is characterized in that the retreat instruction operation is a simultaneous operation on two locations on the input device that are separated by a predetermined distance.

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