Injection device and injection molding machine

Abstract

To provide an injection device that enables stable feeding of granular resin into a heating cylinder by activating a vibration generator at an appropriate timing.SOLUTION: The injection device performs injection processing by advancing a screw within the heating cylinder to inject plasticized resin into the cavity, metering processing that meters the plasticized resin to be injected next into the space ahead of the screw in the heated cylinder by rotating and retracting the screw, thereby plasticizing the granular resin supplied to the heating cylinder through a hopper and vibration processing that operates a vibration generator during the metering processing to supply the granular resin in the hopper into the heating cylinder.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an injection device that injects plasticized resin into a mold, and an injection molding machine equipped with the injection device. [Background technology]

[0002] Conventionally, injection molding machines have been known that plasticize granular resin (pellets) supplied from a hopper in a heating cylinder and then inject the plasticized resin into a mold. In such injection molding machines, pellets can sometimes get stuck in the hopper, preventing smooth supply to the heating cylinder.

[0003] To solve this problem, there is a technique for preventing pellets from adhering to the wall surface of a hopper by vibrating the hopper with a vibration generator (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-192526 Summary of the Invention [Problem to be solved by the invention]

[0005] However, if the vibration generator is constantly operated, not only will the power consumption of the injection molding machine increase, but it may also impair stability when the plasticized resin is injected into the mold.

[0006] The present invention has been made in consideration of the above circumstances, and its purpose is to provide an injection device that can stably supply granular resin to a heating cylinder by activating a vibration generating device at an appropriate timing. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides an injection device that injects plasticized resin into the cavity of a clamped mold, comprising a hopper through which granular resin molded into granules is passed, a heating cylinder to which the granular resin that has passed through the hopper is supplied, a screw that retracts inside the heating cylinder to plasticize the granular resin and advances inside the heating cylinder to inject the plasticized resin into the cavity, a vibration generator that vibrates the hopper, and a control device that controls the operation of the injection device, wherein the control device performs an injection process in which the screw advances inside the heating cylinder to inject the plasticized resin into the cavity, a metering process in which the screw retracts while rotating to plasticize the granular resin supplied to the heating cylinder through the hopper and measures the plasticized resin to be subsequently injected into the space ahead of the screw in the heating cylinder, and a vibration process in which the vibration generator is operated while the metering process is being performed to supply the granular resin in the hopper into the heating cylinder. [Effects of the Invention]

[0008] According to the present invention, by operating the vibration generating device during the metering process, the granular resin can be stably supplied to the heating cylinder. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of an injection molding machine according to an embodiment of the present invention. [Figure 2] FIG. 1 is a hardware configuration diagram of an injection molding machine. [Figure 3] 10A and 10B are diagrams illustrating examples of mounting positions of vibration generators. [Figure 4] 10 is a flowchart of an injection control process. [Figure 5] 10 is a timing chart showing the execution timing of a weighing process and a vibration process. [Figure 6] 10A to 10C are diagrams showing variations in the manner of vibration generated by a vibration generator. 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 molding material into a mold to form a molded product (hereinafter referred to as "injection molding").

[0011] [Configuration of injection molding machine 10] Fig. 1 is a side view of an injection molding machine 10 according to this embodiment. Fig. 2 is a hardware configuration diagram of the injection molding machine 10. As shown in Figs. 1 and 2, the injection molding machine 10 mainly includes a mold clamping unit 20, an injection unit 30, and a control unit 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 die 22 and the movable die 24 move apart. On the other hand, when the movable die plate 25 moves rightward, the fixed die 22 and the movable die 24 come into contact with each other, forming a cavity (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 die 22 and the movable die 24 are clamped.

[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 (the cavity 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 (hereinafter referred to as a "spiral 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 left and right (hereinafter referred to as "forward and backward") and rotate in the injection molding machine 10. The screw 32 in the heating cylinder 31 is configured to be replaceable. In other words, screws 32 with different specifications (for example, material, shape of the spiral groove, volume of the spiral groove) can be inserted into the heating cylinder 31.

[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] The hopper 33 has an internal space through which the pellets pass. The internal space of the hopper 33 has a truncated cone shape with a cross-sectional area that gradually decreases downward. The hopper 33 has an upper opening and a lower opening. Pellets (or recycled resin) supplied from a raw material supply device (not shown) enter the internal space of the hopper 33 through the upper opening and are supplied to the hopper block 34 (heating cylinder 31) through the lower opening.

[0022] 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 of the mold 21 through the nozzle 36.

[0023] Resins of different types (e.g., different degrees of plasticization) are supplied to the hopper 33 depending on the molded product. The particle size (size of particles) of the pellets supplied to the hopper 33 varies depending on the raw material supply device that supplies raw material to the hopper 33. In addition to pellets, recycled resin may also be supplied to the hopper 33. Recycled resin refers to unnecessary parts (runners) separated from the molded product, resin discharged (purged) from the heating cylinder 31, etc. The ratio of pellets and recycled resin supplied to the hopper 33 gradually changes during the injection control process, which will be described later with reference to FIG. 3.

[0024] [Configuration of control device 60] 2, 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.

[0025] 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).

[0026] 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 vibration generator 40, and a communication IF (Interface) 68 based on various signals output from a rotary encoder 64, a load cell 65 (pressure sensor), and a display / input device 67.

[0027] The mold opening / closing motor 28, the injection motor 37, and the metering motor 38 are servo motors that generate driving forces to open and close the mold 21, to move the screw 32 back and forth, and to rotate the screw 32, for example, under the control of a servo amplifier (not shown).

[0028] 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.

[0029] The load cell 65 is a pressure sensor that detects the pressure (back pressure) applied to the screw 32. More specifically, the load cell 65 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 65.

[0030] The display input device 67 is a user interface that includes a display (display 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.

[0031] The communication IF 68 is an interface for communicating with an external device via a communication network. The communication network may be, for example, the Internet, a public line, a wired LAN, a wireless LAN, or a combination thereof. The control device 60 may communicate with, for example, a raw material supply device via the communication IF 68. More specifically, the control device 60 may receive the particle size and the proportion of recycled resin of the pellets to be supplied to the hopper 33 from the raw material supply device via the communication IF 68. As another example, the control device 60 may receive an input operation from an operator via the display / input device 67 to input the particle size and the proportion of recycled resin of the pellets to be supplied to the hopper 33.

[0032] The vibration generator 40 is a device that generates vibrations under the control of the control device 60. The vibration generator 40 is a device that vibrates the hopper 33 to supply the pellets in the hopper 33 into the heating cylinder 31. As one example, the vibration generator 40 may be a device that rotates an eccentric shaft when air is supplied to it. As another example, the vibration generator 40 may be an electric vibrator.

[0033] 3A and 3B are diagrams showing examples of the mounting position of the vibration generator 40. As one example, the vibration generator 40 may be mounted on the outer surface of the hopper 33, as shown in FIG. 3A. As another example, the vibration generator 40 may be mounted on the outer surface of the hopper block 34, as shown in FIG. 3B. As yet another example, the vibration generator 40 may be mounted on the outer surface of a connecting pipe 39 that connects the hopper 33 and the hopper block 34 and through which pellets discharged from the lower end opening of the hopper 33 pass, as shown in FIG. 3C.

[0034] The bottom opening of the hopper 33, which has the smallest cross-sectional area, may become a bottleneck, hindering the supply of pellets to the hopper block 34 (heating cylinder 31). In other words, the pellets may become clogged in the bottom opening, which has the smallest cross-sectional area. Therefore, it is desirable to install the vibration generator 40 in a position where the pellets can pass through the bottom opening smoothly. The installation location of the vibration generator 40 can be changed as appropriate depending on, for example, the shape of the hopper 33, the particle size of the pellets supplied to the hopper 33, the proportion of recycled resin, the supply speed of the pellets to the heating cylinder 31, etc.

[0035] As one example, the vibration generator 40 may be disposed upstream of the bottom opening (bottleneck) of the hopper 33 in the flow of pellets, as shown in Figure 3(A). As another example, the vibration generator 40 may be disposed downstream of the bottom opening of the hopper 33 in the flow of pellets, as shown in Figures 3(B) and 3(C). As yet another example, the vibration generator 40 may be disposed in a portion with a relatively thin wall thickness, as shown in Figures 3(A) and 3(C).

[0036] [Injection control processing] 4 is a flowchart of the injection control process. The injection control process is a process for molding a molded product by injecting the plasticized resin filled in the heating cylinder 31 into the cavity of the clamped mold 21. The control device 60 starts the injection control process in response to a molding instruction being input through the display input device 67, for example. The molding instruction includes, for example, the number of molded products to be molded (hereinafter referred to as the "molding number").

[0037] 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, and the spiral groove of the screw 32 on the tip side of the hopper 33 is filled with resin (pellets, resin in the process of being plasticized, plasticized resin).

[0038] First, the control device 60 closes and clamps the mold 21 by rotating the mold opening / closing motor 28 (S11). This forms a cavity in the mold 21. The processing of step S11 is an example of a mold clamping process.

[0039] Next, after the mold clamping process (S11) is completed, the control device 60 rotates the injection motor 37 in the forward direction to move the screw 32 forward (S12). 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. The process of step S12 is an example of an injection process.

[0040] Next, after the injection process (S12) is completed, the control device 60 rotates and retracts the screw 32, thereby plasticizing the granular resin supplied to the heating cylinder 31 through the hopper 33, and measures the plasticized resin to be injected next into the space in front of the screw 32 of the heating cylinder 31. The control device 60 also adjusts the retraction speed of the screw 32 so that the back pressure of the screw 32 (the pressure that moves the screw 32 backward) detected by the load cell 65 approaches a target value. The process of step S13 is an example of a metering process.

[0041] Furthermore, the control device 60 executes a vibration process while the weighing process is being performed (in other words, in parallel with the weighing process). The vibration process is a process in which the vibration generator 40 is activated to vibrate the hopper 33, thereby stably supplying the pellets in the hopper 33 into the heating cylinder 31. The relationship between the weighing process and the vibration process will be described later with reference to FIGS. 5 and 6.

[0042] Next, after the measurement process (S13) is completed, the control device 60 rotates the mold opening / closing motor 28 to open the mold 21, and causes the robot arm to remove the molded product from the opened mold 21 (S14). The process of step S14 is an example of a removal process.

[0043] Next, after the removal process (S14) is completed, the control device 60 determines whether the number of molded articles molded in the injection control process has reached the molding number specified in the molding instruction (S15). If the number of molded articles has not reached the molding number (S15: No), the control device 60 executes the processes from step S11 onwards again. That is, the control device 60 repeatedly executes the processes from step S11 to S14 until the number of molded articles reaches the molding number.

[0044] Furthermore, the control device 60 ends the injection control process when the number of molded articles reaches the molding quantity (S15: Yes). As another example, the control device 60 may end the injection control process when an operator's operation to instruct the end of the injection control process is received through the display input device 67 (S15: Yes).

[0045] [Relationship between weighing process and vibration process] 5 is a timing chart showing the timing of the weighing process and the vibration process. As shown in FIG. 5, the control device 60 performs the weighing process and the vibration process in parallel, thereby stably supplying the plasticized and weighed pellets into the heating cylinder 31.

[0046] As an example, as shown in FIG. 5(A), the control device 60 may start the vibration treatment (start the operation of the vibration generator 40) simultaneously with the start of the weighing treatment, and may end the vibration treatment (end the operation of the vibration generator) simultaneously with the end of the weighing treatment. This causes the hopper 33 to vibrate constantly during the weighing treatment, so that the pellets in the hopper 33 are smoothly supplied to the heating cylinder 31 without clogging at the lower end opening. The vibration treatment may also be started after a predetermined time has elapsed since the start of the weighing treatment. Furthermore, the vibration treatment may also be ended after a predetermined time has elapsed since the start of vibration. In other words, the start and end of the vibration treatment do not have to be simultaneous with the start and end of the weighing treatment.

[0047] As another example, as shown in FIG. 5(B), after the retreat speed of the screw 32 exceeds the threshold value for the first time after the start of the metering process (in other words, during the period during which the retreat speed of the screw 32 is adjusted so that the back pressure of the screw 32 approaches the target value), the control device 60 may execute vibration processing (activate the vibration generator 40) during the period during which the retreat speed of the screw 32 is below the threshold value, and stop vibration processing (stop the vibration generator 40) during the period during which the retreat speed of the screw 32 is equal to or greater than the threshold value.

[0048] More specifically, in the metering process, the control device 60 adjusts the retraction speed of the screw 32 so that the back pressure of the screw 32 approaches a target value. The back pressure of the screw 32 changes depending on the amount of plasticized resin filled in the space ahead of the screw 32 in the heating cylinder 31. That is, if pellets clog the lower end opening of the hopper 33 and the amount of pellets supplied to the heating cylinder 31 decreases, the back pressure of the screw 32 becomes difficult to increase, and as a result, the retraction speed of the screw 32 also slows. Therefore, as shown in FIG. 5(B), by performing the vibration process only during the period when the retraction speed of the screw 32 is below a threshold, the amount of pellets supplied to the heating cylinder 31 can be restored to its original level.

[0049] 5(B), the start threshold for starting the vibration process and the stop threshold for stopping the vibration process may be different values. More specifically, the stop threshold may be set to a value greater than the start threshold. That is, the control device 60 may start the vibration process when the retraction speed of the screw 32 falls below the start threshold, and may stop the vibration process when the retraction speed of the screw 32 exceeds the stop threshold.

[0050] [Vibration mode] 6 is a diagram showing variations in the manner (for example, amplitude, frequency, rhythm) of vibration generated by vibration generator 40. As shown in FIG. 6, vibration generator 40 may be configured to be able to change the manner of vibration under the control of control device 60. The manner of vibration may include, for example, at least one of amplitude (vibration strength), frequency (number of vibrations per unit time), and rhythm (constant, random).

[0051] As one example, the control device 60 may change the amplitude of the vibration or the frequency of the vibration as shown in Figures 6(A) and 6(B). As another example, the control device 60 may generate vibrations with a constant rhythm as shown in Figures 6(A) and 6(B), or may generate vibrations with a random rhythm as shown in Figure 6(C). As yet another example, the control device 60 may combine changes in amplitude, frequency, and rhythm as shown in Figure 6(C).

[0052] In addition, the control device 60 may change the type of vibration generated by the vibration generating device 40 according to various input parameters (e.g., the retraction speed of the screw 32, the type of resin supplied to the hopper 33, and instructions from the operator via the display input device 67).

[0053] As an example, the control device 60 may change the type of vibration generated by the vibration generator 40 depending on the retraction speed of the screw 32 during the metering process. For example, the control device 60 may increase the amplitude of the vibration generated by the vibration generator 40 as the retraction speed of the screw 32 decreases. This causes the hopper 33 to vibrate more strongly as the amount of pellets supplied to the heating cylinder 31 decreases, allowing the pellet supply amount to be quickly restored.

[0054] As another example, the control device 60 may change the type of vibration generated by the vibration generator 40 depending on the type of granular resin supplied to the hopper 33. The type of granular resin may refer to at least one of the following: the particle size (size of the pellets), the specific gravity (weight) of the pellets, the shape (mainly length) of the pellets, and the proportion of recycled resin. The control device 60 may also obtain the type of granular resin supplied to the hopper 33 from the raw material supply device via the communication IF 68, or from the operator via the display / input device 67.

[0055] As yet another example, the control device 60 may allow the operator to input the type of vibration to be generated by the vibration generator 40 via the display / input device 67. This allows the operator to determine the type of vibration that can stably supply pellets from the hopper 33 to the heating cylinder 31 through trial and error.

[0056] [Effects of the embodiment] According to the above embodiment, by operating the vibration generator 40 during the weighing process, the pellets to be plasticized and weighed can be stably supplied from the hopper 33 to the heating cylinder 31. Furthermore, by stopping the vibration generator 40 during the execution of processes other than the weighing process, it is possible to reduce the power consumption of the injection molding machine 10. Furthermore, by stopping the vibration generator 40 during the execution of the injection process, it is possible to stably inject the plasticized resin.

[0057] 5(A), the vibration generator 40 is always activated during the weighing process, which prevents pellets from clogging the hopper 33. On the other hand, the vibration generator 40 is selectively activated when pellets are clogged (i.e., when the retraction speed of the screw 32 falls below a threshold), which makes it possible to both eliminate pellet clogging and reduce power consumption.

[0058] Furthermore, according to the above embodiment, the amplitude of vibration is increased as the amount of pellets supplied decreases (i.e., the retraction speed of the screw 32 decreases), so that pellet clogging in the hopper 33 can be quickly eliminated.

[0059] Furthermore, according to the above embodiment, by changing the vibration mode depending on the type of granular resin supplied to the hopper 33, the supply of pellets from the hopper 33 to the heating cylinder 31 can be further stabilized.

[0060] 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]

[0061] 10... injection molding machine, 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... vibration generator, 60... control device, 61... CPU, 62... memory, 64... rotary encoder, 65... load cell, 67... display input device, 68... communication IF

Claims

1. In an injection device that injects a plasticized resin into a cavity of a clamped mold, a hopper through which the granular resin formed into granules passes; a heating cylinder to which the granular resin that has passed through the hopper is supplied; a screw that moves backward inside the heating cylinder to plasticize the granular resin and moves forward inside the heating cylinder to inject the plasticized resin into the cavity; a vibration generator that vibrates the hopper; a control device for controlling the operation of the injection device, The control device an injection process injecting the plasticized resin into the cavity by advancing the screw within the heated cylinder; a measuring process in which the screw is rotated and moved backward to plasticize the granular resin supplied to the heating cylinder through the hopper, and the plasticized resin to be subsequently injected into a space in front of the screw in the heating cylinder is measured; and a vibration process for supplying the granular resin in the hopper into the heating cylinder by operating the vibration generating device during the metering process.

2. 2. The injection device according to claim 1, The control device The vibration process is started simultaneously with the start of the weighing process, The injection device is characterized in that the vibration process is completed simultaneously with the completion of the measurement process.

3. 2. The injection device according to claim 1, The control device In the metering process, adjusting the retreat speed of the screw so that the back pressure of the screw approaches a target value; The vibration process is performed during a period in which the retreat speed is less than a threshold value; The injection device is characterized in that the vibration processing is stopped during a period in which the retraction speed is equal to or greater than the threshold value.

4. 4. The injection device according to claim 3, The injection apparatus is characterized in that the control device increases the amplitude of the vibration generated by the vibration generating device as the retraction speed decreases.

5. 2. The injection device according to claim 1, The injection device is characterized in that the control device changes the type of vibration generated by the vibration generating device depending on the type of the granular resin during the vibration treatment.

6. a mold clamping device that opens, closes, and clamps the mold; An injection molding machine comprising the injection device according to claim 1.

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