JP7190916B2 - Injection molding machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to an injection molding machine that injects a plasticized resin into a mold to manufacture an injection-molded product.

Patent Literature 1 discloses a vertical injection molding machine provided with a heating cylinder that moves up and down between a contact position that contacts a resin injection hole of a mold and a retraction limit position above the contact position. there is Further, Japanese Patent Laid-Open No. 2002-200002 describes that a purge operation is performed to discharge the plasticized resin in the heating cylinder.

Japanese Unexamined Patent Application Publication No. 2012-153110

In the injection molding machine described in Patent Literature 1, the operator sets the tray for receiving the plasticized resin in the locating section immediately below the heating cylinder before executing the purge operation, and removes need to remove. Furthermore, if a large amount of plasticized resin is discharged during the purge operation, the operator needs to remove the plasticized resin in the tray during the purge operation.

Therefore, in the injection molding machine with the above configuration, there is a problem that the operator has a heavy workload when performing the purging operation. This problem may occur not only in vertical injection molding machines but also in horizontal injection molding machines in which the heating cylinder moves horizontally.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and it is an object of the present invention to provide an injection molding machine that reduces the work load on the operator during the purge operation.

In order to solve the above-mentioned problems, the present invention provides an injection molding machine comprising a mold clamping unit that opens and closes a mold and clamps the mold, and an injection unit that injects a plasticized resin, wherein the injection unit comprises a plasticized resin A heating cylinder having a nozzle formed at its tip for injecting the A conveyor is provided on the discharge path of the plasticized resin from the heating cylinder and conveys the plasticized resin discharged from the nozzle to the outside of the injection molding machine, and the conveyor is provided for discharging the plasticized resin from the nozzle. The conveying speed is switched in conjunction with the discharge speed of the injection unit, the injection unit has a screw that can rotate and move forward and backward within the heating cylinder, and the conveyer moves the injection unit to the waiting position while the The plasticized resin is conveyed at a first speed when the screw is moving, and the plasticized resin is conveyed at a second speed slower than the first speed when the screw is stopped. do.

According to the above configuration, the plasticized resin discharged from the heating cylinder when the injection unit is at the standby position is automatically conveyed to the outside of the injection molding machine by the conveyor. As a result, it is possible to reduce the work burden on the operator, such as attaching and detaching the pan when performing the purge operation. Further, if the conveying speed of the conveyor is too slow with respect to the discharge speed of the plasticized resin, the plasticized resin will form lumps on the conveying surface of the conveyor. On the other hand, if the conveying speed of the conveyor is too fast relative to the discharge speed of the plasticized resin, there is a possibility that power will be wasted or the motor that drives the conveyor will overheat. Therefore, it is desirable to switch the conveying speed of the conveyor in conjunction with the discharge speed of the plasticized resin, as in the above configuration. Furthermore, by doing so, it is also possible to remove the resin dripping from the nozzle hole while the screw is stopped.

For example, the conveyer conveys the plasticized resin at the first speed during a purge operation in which the screw is advanced to discharge the plasticized resin in the heating cylinder, and the screw is rotated backward to move the heating cylinder. It may be characterized in that the plasticized resin is conveyed at a third speed slower than the first speed during the metering operation in which the plasticized resin is stored inside.

Further, a lid is provided that moves between a closed position that closes the nozzle hole at the tip of the nozzle and an open position that opens the nozzle hole, and the injection unit disposes the cover at the closed position and performs the metering operation. and placing the lid in the open position to perform the purge operation.

According to the above configuration, it is possible to prevent the plasticized resin from leaking from the heating cylinder when the injection unit is at the standby position. In addition, by placing the lid in the closed position and performing the metering operation, the back pressure in the heating cylinder is increased and the efficiency of the metering operation is improved.

Moreover, it may be characterized by comprising a cooling device for cooling the plasticized resin conveyed on the conveyor.

The melted plasticized resin sticks to the surface of the conveyor and is difficult to peel off. Therefore, according to the above configuration, it is possible to expect the effect of promoting solidification of the plasticized resin and making it easier to separate from the surface of the conveyor.

In order to solve the above-mentioned problems, the present invention provides an injection molding machine comprising a mold clamping unit that opens and closes a mold and clamps the mold, and an injection unit that injects a plasticized resin, wherein the injection unit comprises a plasticized resin A heating cylinder having a nozzle formed at its tip for injecting the A conveyor is provided on a discharge path of the plasticized resin from the heating cylinder and conveys the plasticized resin discharged from the nozzle to the outside of the injection molding machine, and the injection molding machine is configured such that the standby position is the It is a vertical conveyor located vertically above the injection position, and after the injection unit moves to the standby position, the conveyor moves to a forward position directly below the heating cylinder, and the injection unit moves to the injection position. Before the heating cylinder is moved, the heating cylinder is moved to a retracted position out of the moving path.

Further, the conveyor may move forward and backward between the forward position and the retracted position along the conveying direction of the plasticized resin.

According to the above configuration, the space required for moving the conveyor can be reduced.

As another example, the injection molding machine is a horizontal type in which the injection position and the standby position are horizontally separated, and the conveyor is fixed directly below the nozzle of the heating cylinder at the standby position. It may be characterized by

Further, a guide plate that moves between a guide position on the moving path of the heating cylinder and a retracted position away from the moving path of the heating cylinder is provided, and the conveyor moves directly below the guide plate at the guide position. The guide plate moves to the guide position after the injection unit moves to the standby position, and moves to the retracted position before the injection unit moves to the injection position. It may be a feature.

According to the above configuration, the plasticized resin vigorously discharged from the heating cylinder by the purge operation collides with the guide plate at the guide position and is guided to the conveyor. As a result, in the horizontal injection molding machine, the plasticized resin discharged by the purge operation can be reliably and efficiently discharged to the outside of the injection molding machine through the conveyor.

According to the present invention, the plasticized resin discharged from the heating cylinder when the injection unit is at the standby position is automatically conveyed to the outside of the injection molding machine by the conveyor. As a result, it is possible to reduce the work burden on the operator, such as attaching and detaching the pan when performing the purge operation.

1 is a front view of a vertical injection molding machine according to a first embodiment; FIG. It is an expansion schematic diagram of an injection unit. It is a hardware block diagram of an injection molding machine. 4 is a flowchart of resin discharge processing; 6 is a flowchart of purge control processing; It is a side view of a horizontal injection molding machine according to a second embodiment. It is the front view which looked at the heating cylinder from the front end side.

An injection molding machine 10 according to the present invention will be described below with reference to the drawings. It should be noted that the embodiments of the present invention described below are merely examples of embodying the present invention, and the scope of the present invention is not limited to the scope of the description of the embodiments. Therefore, the present invention can be implemented by adding various changes to the embodiments.

(First embodiment)
FIG. 1 is a front view of an injection molding machine 10 according to the first embodiment. FIG. 2 is an enlarged schematic diagram of the injection unit 30. As shown in FIG. FIG. 3 is a hardware block diagram of the injection molding machine 10. As shown in FIG. The injection molding machine 10 is a device that injects a plasticized resin into a mold to manufacture an injection-molded product. The injection molding machine 10 according to the first embodiment is a so-called "vertical type". As shown in FIGS. 1 to 3, the injection molding machine 10 mainly includes a mold clamping unit 20, an injection unit 30, an operation panel 40, and a controller 50. FIG.

The mold clamping unit 20 opens and closes the mold 21 and clamps the mold. Specifically, the mold clamping unit 20 includes a fixed die plate 23 that supports the fixed mold 22, a movable die plate 25 that supports the movable mold 24 directly above the fixed mold 22, and the movable die plate 25 with tie bars. 26, and a mold opening/closing motor 61 for vertically moving the mold.

The die opening/closing motor 61 is a servomotor that moves the movable die plate 25 in the vertical direction. The driving force of the mold opening/closing motor 61 is transmitted to the movable die plate 25 through, for example, a toggle link mechanism (not shown). As shown in FIG. 1, when the movable die plate 25 rises, the fixed die 22 and the movable die 24 are separated. On the other hand, when the movable die plate 25 descends, the fixed die 22 and the movable die 24 come into contact with each other, forming a cavity (internal space) inside the die 21 . Further downward pressure is applied to the movable die plate 25, and the fixed mold 22 and the movable mold 24 are clamped.

The injection unit 30 plasticizes, weighs, and injects a resin supplied from a hopper (not shown). The injection unit 30 according to the first embodiment is arranged above the mold clamping unit 20 . The injection unit 30 includes a heating cylinder 31, a screw 32, a conveyor 33, a fan 34, a lid 35, a nozzle touch motor 62, a weighing motor 63, an injection motor 64, a conveyor advancement/retraction motor 65, and a conveyor drive. A motor 66 and a lid advancing/retreating motor 67 are mainly provided.

The heating cylinder 31 is a cylindrical member that extends vertically. In the heating cylinder 31, a nozzle hole 36a of a nozzle 36 for injecting plasticized resin is formed at the tip (lower end), and a supply port (not shown) for receiving resin supply from the hopper is formed at the base end (upper end). ing. A linear internal space is formed inside the heating cylinder 31 from the supply port to the nozzle 36 . A band heater (not shown) for heating the heating cylinder 31 may be attached to the outer peripheral surface of the heating cylinder 31 .

The nozzle touch motor 62 is a servomotor that vertically moves the injection unit 30 . The driving force of the nozzle touch motor 62 is transmitted to the injection unit 30, and the injection unit 30 moves vertically between the injection position (FIG. 2A) and the standby position (FIGS. 2B to 2D). . The injection position is a position where the nozzle 36 at the tip of the heating cylinder 31 enters an opening (not shown) provided in the movable die plate 25 and the internal space of the heating cylinder 31 communicates with the cavity of the mold 21 . The standby position is a position where the nozzle 36 at the tip of the heating cylinder 31 is withdrawn from the opening of the movable die plate 25 and the heating cylinder 31 and the mold 21 are separated. The standby position according to the first embodiment is a position vertically above the ejection position.

The screw 32 is a long rod-shaped member having a spiral groove formed on its outer peripheral surface. The screw 32 is accommodated in the internal space of the heating cylinder 31 so as to be rotatable and forward and backward. The metering motor 63 is a servomotor that rotates the screw 32 within the heating cylinder 31 . The injection motor 64 is a servomotor that moves the screw 32 back and forth within the heating cylinder 31 . The injection unit 30 performs a metering operation, an injection operation, and a purge operation by rotating or moving the screw 32 back and forth within the heating cylinder 31 .

The metering operation is an operation for storing a predetermined amount of plasticized resin on the tip side (nozzle 36 side) of the heating cylinder 31 by rotating the screw 32 . At this time, the resin supplied to the heating cylinder 31 is plasticized by frictional heat and shearing heat generated between the heating cylinder 31 and the screw 32 and heat generated by the band heater. Also, the plasticized resin moves to the tip side of the heating cylinder 31 along the spiral groove of the screw 32 and accumulates on the tip side of the heating cylinder 31 . As a result, the screw 32 retreats while rotating inside the heating cylinder 31 .

The injection operation and the purge operation are operations for injecting (discharging) the plasticized resin stored at the tip side of the heating cylinder 31 from the heating cylinder 31 through the nozzle 36 by advancing the screw 32 . In this specification, the operation of injecting the plasticized resin from the heating cylinder 31 when the injection unit 30 is at the injection position is referred to as "injection operation", and when the injection unit 30 is at the standby position, the injection of the plasticized resin from the heating cylinder 31 is The operation of discharging is referred to as "purge operation".

The conveyor 33 serves to convey the plasticized resin discharged from the heating cylinder 31 to the outside of the injection molding machine 10 when the injection unit 30 is at the standby position. That is, the conveyor 33 is arranged on the discharge path (immediately below the nozzle hole 36a) of the plasticized resin from the heating cylinder 31 at the standby position. The conveyor forward/backward motor 65 is a servomotor that moves the conveyor 33 back and forth. The conveyor drive motor 66 is a servomotor that drives the conveyor 33 to rotate.

The conveyor 33 is transmitted with the driving force of the conveyor advancing/retreating motor 65, and advances back and forth between the forward position (FIGS. 2(C) and (D)) and the retracted position (FIGS. 2(A) and (B)). do. The forward position is a position where the conveying surface (upper surface) of the conveyor 33 is arranged directly below the nozzle 36 (nozzle hole 36a) at the tip of the heating cylinder 31 at the standby position. The retracted position is a position where the conveyor 33 is out of the moving path of the heating cylinder 31 . The forward position and the retracted position are positions spaced apart in the conveying direction of the plasticized resin by the conveyor 33 (that is, the horizontal direction in FIG. 2). That is, the conveyor 33 moves forward and backward along the conveying direction of the plasticized resin.

When the conveyor 33 is in the forward position, the plasticized resin discharged from the nozzle 36 (nozzle hole 36a) at the tip of the heating cylinder 31 in the standby position lands on the conveying surface of the conveyor 33, and the injection unit 30 (heating cylinder 31) is in standby. Unable to move from position to injection position. On the other hand, when the conveyor 33 is at the retracted position, the plasticized resin discharged from the nozzle 36 (nozzle hole 36a) at the tip of the heating cylinder 31 at the standby position does not land on the conveying surface of the conveyor 33, and the injection unit 30 (heating cylinder 31 ) can move between the injection position and the standby position.

In addition, the conveyor 33 receives the driving force of the conveyor drive motor 66, and rotates in a direction (counterclockwise in FIG. 2) in which the plasticized resin that has landed on the conveying surface is discharged to the outside of the injection molding machine 10. In addition, the conveyor 33 may be configured so that the transport speed can be switched. The conveyor 33 according to the first embodiment is switchable at least between high speed (first speed) and low speed (second speed). The first speed is set, for example, based on the discharge speed of the plasticized resin in the purge operation. The second speed is a speed slower than the first speed.

The fan 34 is a cooling device that serves to cool the plasticized resin conveyed on the conveyor 33 . Specifically, the fan 34 blows air toward the conveying surface of the conveyor 33 . Also, the fan 34 is fixed at a predetermined position on the conveyor 33 . That is, the fan 34 moves back and forth integrally with the conveyor 33 that moves between the forward position and the retracted position. Also, the blowing speed of the fan 34 (air blowing amount per unit time) may be switchable in conjunction with the conveying speed of the conveyor 33 .

The lid 35 abuts on the tip of the heating cylinder 31 to close the nozzle 36 . The lid advancement/retraction motor 67 is a servomotor that moves the lid 35 forward and backward. The lid 35 is transmitted with the driving force of the lid advancing/retreating motor 67, and has a closed position (FIG. 2(D)) where the nozzle 36 is closed and an open position (FIGS. 2(A)-(C)) where the nozzle 36 is opened. move back and forth between

As shown in FIG. 2, the injection unit 30 comprises a box 37 containing a heating cylinder 31, a conveyor 33, and a lid 35. As shown in FIG. The box 37 has slits 37a, 37b, and 37c through which the heating cylinder 31, conveyor 33, and lid 35 are inserted. That is, the heating cylinder 31, the conveyor 33, and the lid 35 advance and retreat with respect to the inner space of the box 37 through the slits 37a, 37b, and 37c.

Note that the nozzle 36 at the tip of the heating cylinder 31 is always positioned in the inner space of the box 37 . This prevents the operator from touching the plasticized resin injected from the nozzle 36 . However, the box 37 may have a door (not shown) that exposes the internal space for maintenance.

The operation panel 40 is a user interface including a display for displaying various information to be notified to the operator, and buttons, switches, dials, and the like for receiving operations by the operator. Further, the operation panel 40 may include a touch panel superimposed on the display. The operation panel 40 receives, for example, an operator's operation to instruct the start of the injection operation and an operator's operation to instruct the start of the purge operation, and outputs an operation signal corresponding to the received operation to the controller 50 .

A controller 50 controls the operation of the entire injection molding machine 10 . The controller 50 acquires an operation signal output from the operation panel 40 and an encoded signal output from an encoder (not shown) of each motor 61-67. The controller 50 then drives the motors 61 to 67 and the fan 34 based on the acquired various signals.

The controller 50 includes, for example, a CPU (Central Processing Unit) 51 as computing means, a ROM (Read Only Memory) 52 for storing various programs, and a RAM (Random Access Memory) 53 as a work area for the computing means. Then, the CPU 51 may read out and execute the programs stored in the ROM 52 to realize each process described later.

However, the specific configuration of the controller 50 is not limited to this, and may be realized by hardware such as ASIC (Application Specific Integrated Circuit) and FPGA (Field-Programmable Gate Array).

Next, operation of the injection molding machine 10 according to the first embodiment will be described with reference to FIGS. 4 and 5. FIG. FIG. 4 is a flowchart of resin discharge processing. FIG. 5 is a flowchart of purge control processing. The resin discharge process is started, for example, when injection molding is finished. As shown in FIG. 2A, at the start of the resin discharging process, the injection unit 30 (heating cylinder 31) is placed at the injection position, the conveyor 33 is placed at the retracted position, and the lid 35 is placed at the open position. ing.

First, the controller 50 drives the nozzle touch motor 62 to raise the injection unit 30 (heating cylinder 31) from the injection position to the standby position (S11). As a result, as shown in FIG. 2B, the heating cylinder 31 is raised and separated from the mold 21, exposing the nozzle hole 36a of the nozzle 36. Then, as shown in FIG.

Next, the controller 50 drives the conveyor advance/retreat motor 65 and the conveyor drive motor 66 to advance the conveyor 33 from the retracted position to the advanced position and rotate the conveyor 33 at a low speed (S12). As a result, as shown in FIG. 2C, the conveyor 33 is arranged directly below the heating cylinder 31 at the standby position. That is, the controller 50 moves the conveyor 33 to the forward position after moving the injection unit 30 (heating cylinder 31) to the standby position. Also, the controller 50 rotates the fan 34 .

Next, the controller 50 waits for execution of subsequent processes until an instruction is input from the operator through the operation panel 40 (S13). Then, when the operator's operation instructing the execution of the purge operation is received through the operation panel 40 (S13: Purge), the controller 50 executes the purge control process (S14).

As shown in FIG. 5, the controller 50 drives the lid advancement/retraction motor 67 to advance the lid 35 from the open position to the closed position (S21). As a result, as shown in FIG. 2(D), the lid 35 comes into contact with the tip of the heating cylinder 31 and the nozzle 36 is closed. As a result, it is possible to prevent the plasticized resin in the heating cylinder 31 from gradually leaking out of the nozzle 36 (nozzle hole 36a) due to gravity.

Next, the controller 50 rotates the metering motor 63 to rotate and retreat the screw 32 (S22). As a result, the plasticized resin is stored on the tip side of the heating cylinder 31 (measurement operation). Based on the encoded value output from the encoder of the weighing motor 63, the controller 50 waits until the screw 32 reaches a predetermined position (predetermined amount of plasticized resin is stored) before executing subsequent processes. (S23: No).

When the controller 50 determines that the screw 32 has retreated to the predetermined position (S23: Yes), it increases the drive current supplied to the conveyor drive motor 66 to switch the conveyor 33 to high speed rotation (S24). The controller 50 also drives the lid forward/backward motor 67 to retract the lid 35 from the closed position to the open position (S25). As a result, the state shown in FIG. 2(D) returns to the state shown in FIG. 2(C). Note that the processing of steps S24 and S25 may be reversed in processing order, or may be executed in parallel.

Next, the controller 50 drives the injection motor 64 to advance the screw 32 (S26). As a result, the plasticized resin stored on the tip side of the heating cylinder 31 is discharged through the nozzle 36 (purge operation). The plasticized resin discharged from the nozzle 36 lands on the conveying surface of the conveyor 33 and is conveyed to the outside of the injection molding machine 10 by the conveyor 33 rotating at high speed. Furthermore, the plasticized resin is cooled by the air blown from the fan 34 while being conveyed on the conveyor 33 .

Next, the controller 50 determines whether or not the number of times the purge operation has been performed (that is, the number of repetitions of steps S21 to S26) has reached a predetermined number (S27). A predetermined default value may be stored in the RAM 53 or may be specified by the operator through the operation panel 40 for the number of times the purge operation is performed.

Then, when the controller 50 determines that the number of purge operations performed has not reached the predetermined number (S27: No), the controller 50 reduces the drive current supplied to the conveyor drive motor 66 to switch the conveyor 33 to low speed rotation. (S28). Then, the controller 50 returns to step S21 and continues the process.

On the other hand, when the controller 50 determines that the number of purge operations performed has reached the predetermined number (S27: Yes), it reduces the drive current supplied to the conveyor drive motor 66 to switch the conveyor 33 to low speed rotation ( S29). The controller 50 then ends the purge control process. After performing the purge operation a predetermined number of times (S27: Yes), the controller 50 may drive the injection motor 64 to move the screw 32 back and forth within the heating cylinder 31, which is so-called "blank driving". .

Next, returning to FIG. 4, the controller 50 executes the processes after step S13 again. Then, when the controller 50 receives an operator's operation instructing execution of the injection operation through the operation panel 40 (S13: injection), the controller 50 stops the conveyor drive motor 66 and drives the conveyor advancing/retreating motor 65 to cause the conveyor 33 to move. is retracted from the forward position to the retracted position (S15). Further, controller 50 stops fan 34 . As a result, the state shown in FIG. 2(C) returns to the state shown in FIG. 2(B).

Next, the controller 50 drives the nozzle touch motor 62 to lower the injection unit 30 (heating cylinder 31) from the standby position to the injection position (S16). As a result, the state shown in FIG. 2(B) returns to that shown in FIG. 2(A). That is, the controller 50 moves the conveyor 33 to the retracted position before moving the injection unit 30 (heating cylinder 31) to the injection position.

The controller 50 then executes injection molding (S17). Specifically, the controller 50 repeats a mold closing operation, a mold clamping operation, a weighing operation, an injection operation, a mold opening operation, and a molded article discharging operation a predetermined number of times. Since the process of step S17 is already known, detailed description thereof will be omitted. Then, when the injection molding is performed a predetermined number of times, the controller 50 returns to step S11 and continues the processing.

According to the injection molding machine 10 according to the first embodiment, for example, the following effects can be obtained.

According to the first embodiment, the plasticized resin discharged from the heating cylinder 31 at the standby position by the purge operation is automatically conveyed to the outside of the injection molding machine 10 by the conveyor 33 . As a result, it is possible to reduce the work burden on the operator, such as attaching and detaching the pan when performing the purge operation.

Note that if the conveying speed of the conveyor 33 is too slow with respect to the discharge speed of the plasticized resin, the plasticized resin will form lumps on the conveying surface of the conveyor 33 . On the other hand, if the conveying speed of the conveyor 33 is too fast with respect to the discharging speed of the plasticized resin, there is a possibility that power will be wasted or the conveyor drive motor 66 will be overheated. Therefore, it is desirable to switch the conveying speed of the conveyor 33 in conjunction with the discharge speed of the plasticized resin as in the first embodiment.

As a result, the plasticized resin discharged in step S26 is conveyed on the conveying surface of the conveyor 33 in the form of a string. As a result, the slit 37b can be set to the minimum height through which the conveyor 33 can pass, thereby preventing the operator's hand from accidentally entering the inside of the box 37 through the slit 37b.

Further, by closing the nozzle 36 (nozzle hole 36a) with the lid 35 as in the first embodiment, it is possible to prevent the plasticized resin from leaking out of the heating cylinder 31 when the injection unit 30 is at the standby position. Further, by placing the lid 35 in the closed position and performing the weighing operation, the back pressure in the heating cylinder 31 is increased and the efficiency of the weighing operation is improved. The conveyor drive motor 66 may be stopped while the lid 35 is in the closed position (S21 to S25).

On the other hand, lid 35 may be omitted. In this case, the conveying speed of the conveyor 33 during the weighing operation (S22-S23) may be the third speed (medium speed) that is lower than the first speed and higher than the second speed. As a result, the conveying speed of the conveyor 33 can be more accurately linked to the conveying speed of the plasticized resin through the nozzle 36 . However, the relationship between the second speed and the third speed is not limited to the above example, and may be second speed>third speed, or second speed=third speed.

Furthermore, the conveying speed of the conveyor 33 during the weighing operation (S22-S23) may be set to the first speed. That is, the controller 50 causes the conveyor 33 to convey the plasticized resin at the first speed when the screw 32 is moving (rotating, moving forward and backward) (S22 to S26), and when the screw 32 is stopped (S12-S13), the conveyor 33 may be caused to convey the plasticized resin at the second speed.

Further, the plasticized resin in a melted state sticks to the surface of the conveyor 33 and becomes difficult to peel off. Therefore, by cooling the plasticized resin on the conveyor 33 with the fan 34 as in the first embodiment, the solidification of the plasticized resin is accelerated, and the effect of making it easier to separate from the surface of the conveyor 33 can be expected. A specific example of the cooling device is not limited to the fan 34, and may be a device that uses a refrigerant to generate cool air.

Moreover, in the first embodiment, an example in which the conveyor 33 is moved forward and backward along the direction of transport of the plasticized resin has been described. As a result, the space required for moving the conveyor 33 is reduced, so the slit 37b can be made smaller. However, the movement locus of the conveyor 33 is not limited to the above example, and may swing on a horizontal plane.

(Second embodiment)
Next, an injection molding machine 10A according to a second embodiment will be described with reference to FIGS. 6 and 7. FIG. FIG. 6 is a side view showing a schematic configuration of the injection molding machine 10A. FIG. 7 is a front view of the heating cylinder 31 viewed from the tip side. Components having functions common to those of the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof are omitted.

An injection molding machine 10A according to the second embodiment is a so-called "horizontal type" in which an injection unit 30 (heating cylinder 31) moves horizontally between an injection position and a standby position separated in the horizontal direction. That is, the injection molding machine 10A according to the second embodiment differs from the injection molding machine 10 according to the first embodiment in that the positional relationships of the main components 22 to 26 and 31 to 32 are reversed by 90°. .

Further, the injection molding machine 10A according to the second embodiment includes a guide plate 38 instead of the lid 35. As shown in FIG. However, the injection molding machine 10A may be provided with the lid 35 . The guide plate 38 plays a role of guiding the plasticized resin discharged from the heating cylinder 31 by the purge operation to the conveying surface of the conveyor 33 . The guide plate 38 receives a drive force from a guide plate advancing/retreating motor (not shown), and moves between the retracted position (FIG. 7A) and the guide position (FIG. 7B).

The retracted position is a position away from the movement path of the heating cylinder 31 . The guide position is a position on the moving path of the heating cylinder 31 . That is, when the guide plate 38 is at the retracted position, the plasticized resin discharged from the heating cylinder 31 at the standby position does not land on the guide plate 38, and the injection unit 30 (heating cylinder 31) moves between the standby position and the injection position. can move. On the other hand, when the guide plate 38 is at the guide position, the plasticized resin discharged from the heating cylinder 31 at the standby position lands on the guide plate 38, and the injection unit 30 (heating cylinder 31) cannot move from the standby position to the injection position.

Further, the conveyor 33 according to the second embodiment is fixed directly below the nozzle 36 at the tip of the heating cylinder 31 at the standby position and directly below the guide plate 38 at the guide position. That is, both the plasticized resin leaking little by little from the heating cylinder 31 at the standby position and the plasticized resin discharged vigorously from the heating cylinder 31 at the standby position and landing on the guide plate 38 land on the conveying surface of the conveyor 33. and transported to the outside of the injection molding machine 10A.

The injection molding machine 10A according to the second embodiment executes the processes shown in FIGS. 4 and 5. FIG. However, in the second embodiment, the forward and backward movement of the conveyor in steps S12 and S15 and the processing of steps S21 and S25 are omitted. Further, the controller 50 according to the second embodiment moves the guide plate 38 from the retracted position to the guide position after moving the injection unit 30 (heating cylinder 31) from the injection position to the standby position (that is, immediately after step S11). move to Furthermore, the controller 50 according to the second embodiment moves the guide plate 38 from the guide position to the retracted position before moving the injection unit 30 (heating cylinder 31) from the standby position to the injection position (that is, immediately before step S16). move.

According to the second embodiment, the plasticized resin vigorously discharged from the nozzle 36 at the tip of the heating cylinder 31 by the purge operation collides with the guide plate 38 at the guide position and is guided to the conveying surface of the conveyor 33 . As a result, in the horizontal injection molding machine 10A, the plasticized resin discharged by the purge operation can be reliably and efficiently discharged to the outside of the injection molding machine 10A through the conveyor 33.

10, 10A... Injection molding machine, 20... Mold clamping unit, 21... Mold, 22... Fixed mold, 23... Fixed die plate, 24... Movable mold, 25... Movable die plate, 26... Tie bar, 30... Injection Unit 31 Heating cylinder 32 Screw 33 Conveyor 34 Fan (cooling device) 35 Lid 36 Nozzle 36a Nozzle hole 37 Box 37a, 37b, 37c Slit 38 Guide plate 40 Operation panel 50 Controller 51 CPU 52 ROM 53 RAM 61 Mold opening/closing motor 62 Nozzle touch motor 63 Weighing motor 64 Injection motor 65 Conveyor Advance/retreat motor 66 Conveyor drive motor 67 Lid advance/retreat motor

Claims (8)

In an injection molding machine equipped with a mold clamping unit that opens and closes the mold and clamps the mold, and an injection unit that injects the plasticized resin,
The injection unit moves between an injection position in which a heating cylinder having a nozzle for injecting plasticized resin formed at its tip is communicated with the cavity of the clamped mold, and a standby position in which the cylinder is separated from the mold. move and
a conveyor arranged on a discharge path of the plasticized resin from the heating cylinder at the standby position and conveying the plasticized resin discharged from the nozzle to the outside of the injection molding machine;
The conveyor switches the conveying speed in conjunction with the discharge speed of the plasticized resin from the nozzle,
The injection unit has a screw that can rotate and move forward and backward within the heating cylinder,
The conveyor, when the injection unit is at the standby position,
conveying the plasticized resin at a first speed while the screw is moving;
An injection molding machine, wherein the plasticized resin is conveyed at a second speed slower than the first speed when the screw is stopped. The conveyor is
conveying the plasticized resin at the first speed during a purge operation for discharging the plasticized resin in the heating cylinder by advancing the screw;
2. The method according to claim 1 , wherein the screw is rotated backward to convey the plasticized resin at a third speed slower than the first speed during the metering operation of storing the plasticized resin in the heating cylinder. Injection molding machine. A lid that moves between a closed position that closes the nozzle hole at the tip of the nozzle and an open position that opens the nozzle hole,
The injection unit is
placing the lid in the closed position to perform the weighing operation;
3. The injection molding machine of claim 2 , wherein the purge operation is performed with the lid positioned in the open position. 4. The injection molding machine according to any one of claims 1 to 3 , further comprising a cooling device for cooling the plasticized resin conveyed on the conveyor. In an injection molding machine equipped with a mold clamping unit that opens and closes the mold and clamps the mold, and an injection unit that injects the plasticized resin,
The injection unit moves between an injection position in which a heating cylinder having a nozzle for injecting plasticized resin formed at its tip is communicated with the cavity of the clamped mold, and a standby position in which the cylinder is separated from the mold. move and
a conveyor arranged on a discharge path of the plasticized resin from the heating cylinder at the standby position and conveying the plasticized resin discharged from the nozzle to the outside of the injection molding machine;
The injection molding machine is a vertical type in which the standby position is positioned vertically above the injection position,
The conveyor is
After the injection unit has moved to the standby position, it moves to the forward position directly below the heating cylinder;
An injection molding machine, wherein the injection unit moves to a retracted position out of the moving path of the heating cylinder before moving to the injection position. 6. The injection molding machine according to claim 5 , wherein the conveyor moves back and forth between the forward position and the retracted position along the conveying direction of the plasticized resin. The injection molding machine is a horizontal type in which the injection position and the standby position are horizontally separated,
5. The injection molding machine according to any one of claims 1 to 4 , wherein the conveyor is fixed directly below the nozzle of the heating cylinder at the standby position. A guide plate that moves between a guide position on the movement path of the heating cylinder and a retracted position away from the movement path of the heating cylinder,
The conveyor is fixed directly below the guide plate at the guide position,
The guide plate is
After the injection unit has moved to the standby position, it moves to the guide position;
8. The injection molding machine according to claim 7 , wherein the injection unit moves to the retracted position before moving to the injection position.

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