JP2002036293A - Automatic injection molding system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable an easy and rapid recovery work when a normal molding operation is interrupted due to occurrence of any malfunction during an automatic operation. SOLUTION: When the any malfunction occurs during the automatic operation and the normal molding operation is interrupted, supply of a molding material from a material supply unit 36 to an injection unit 3 is stopped, a mold 5 is released from the unit 3, and the molding material is then discharged from the unit 3. Thereafter, the unit 3 suitable heat insulates. The mold 5 is cooled as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic injection molding system used for injection molding of a thermoplastic resin or the like, and more particularly to a process when a normal molding operation is interrupted due to some abnormality during automatic operation. About.

[0002]

FIG. 4 shows an outline of an example of an automatic injection molding system. In FIG. 1, reference numeral 1 denotes an injection molding machine. The injection molding machine 1 includes a mold clamping device 2 and an injection device 3. The mold clamping device 2 and the injection device 3 are arranged on a base 4. . Mold clamping device 2
Is for opening and closing the fixed mold 6 and the movable mold 7 which are the molds 5 mutually. A fixed platen 8 to which the fixed mold 6 is detachably attached and a movable platen 9 to which the movable mold 7 is detachably attached. And The movable platen 9 is moved in a direction approaching and separating from the fixed platen 8 by, for example, a hydraulically driven mold clamping cylinder 10, thereby opening and closing the fixed mold 6 and the movable mold 7. .

[0003] The injection device 3 has an injection molding machine base.
The mold 5 is mounted on a rail 17 fixed on the base 4.
Are slidably supported in directions approaching and moving away from. The injection molding machine base 16 moves by, for example, driving a hydraulically driven shift cylinder 18. The injection device 3 is of an in-line screw type, and includes a heating cylinder 22 having a nozzle 21 at a distal end portion which is attached to and detached from the fixed die 6 with movement of the injection molding machine base 16. The heating cylinder 22 is provided with a heater 23 serving as a heating means on an outer periphery and has a screw 24 built therein. Further, a hopper 25 is provided on an end of the heating cylinder 22 opposite to the nozzle 21. The hopper 25 has a sensor that detects the amount of molding material (such as pellets) inside it.
26 are provided. The screw 24 is connected via a rod 28 to, for example, a hydraulically driven injection cylinder 27 that drives the screw 24 in its axial direction, that is, in a direction approaching and separating from the mold 5. A gear 30 is spline-fitted to a spline cylinder 29 fixed to the rod 28 in a state where the gear 30 is slidable in the axial direction of the screw 24 and the rod 28 and is prevented from rotating. A gear 32 fixed to a rotation output shaft of a motor 31 meshes with the gear 30. That is, the screw 24 is rotated by the drive of the motor 31.

Further, the injection molding machine 1 is provided with a control panel 33 having various switches for operation and a display at appropriate positions.

The hopper 25 has the hopper
A material supply device 36 for supplying a molding material such as a thermoplastic resin into the inside 25 is connected by a hose 37. The material supply device 36 includes a control panel 38 having various operation switches and a display unit, and also includes a dryer.

A mold temperature controller 41 is connected to the mold 5 by a hose 42 or the like. The mold temperature controller 41 adjusts the temperature of the mold 5 by supplying a cooling medium such as water to a cooling medium passage formed in the mold 5, for example. The mold temperature controller 41 includes a control panel 43 having various switches for operation and a display unit.

Further, although not shown, a take-out device for taking out the formed product from the mold 5 is also provided.

In automatic operation, the mold clamping device 2
, The mold closing and the mold opening are repeated, and the injection device 3 repeats the measuring step, the injection step, and the pressure holding step. In the measuring step, the molding material is supplied into the heating cylinder 22 from the hopper 25, and the heating cylinder 22 is heated by the heater 23 and the shearing force generated by the rotation of the screw 24.
The molding material inside is plasticized, and the plasticized molding material is stored in the heating cylinder 22 on the nozzle 21 side (front side). At this time, the screw 24 retreats away from the mold 5. Then, after the fixed mold 6 and the movable mold 7 are closed, and a predetermined amount of molding material is accumulated in the front part of the heating cylinder 22, the screw 24 advances to the mold 5 side by driving the injection cylinder 27. , Heating cylinders22
The molding material therein is injected from the nozzle 21 into the mold 5 (injection step). After that, screw 24 from injection cylinder 27
The pressure is maintained by the back pressure applied to the pressure (pressure holding step).
Further, the molding material in the mold 5, that is, the molded product is sufficiently cooled and solidified (cooling step), and then the fixed mold 6 and the movable mold 7 are opened, and the molded product is taken out by the take-out device. It is. On the other hand, in the injection device 1, the measuring process is started again, and the above molding cycle is repeated.

When the sensor 26 detects that the molding material in the hopper 25 has decreased below the level of the sensor 26, the molding material is automatically replenished into the hopper 25 from the material supply device 36 and the hopper 25 is refilled. The molding material in the sensor 26
Is reached, the supply of the molding material from the material supply device 36 to the hopper 25 is stopped.

In the automatic operation described above, if any abnormality such as a failure of the apparatus occurs, the injection molding machine 1 stops the molding operation and the unloading apparatus also stops operating. Further, since the molding material in the hopper 25 does not decrease and the molding material in the hopper 25 becomes higher than the level of the sensor 26, the material supply device 36 does not supply the material to the hopper 25. Conventionally, when the molding operation is interrupted due to such an abnormality, the injection molding machine 1 simply issues a warning by a warning means 46 such as a buzzer or a lamp. That is, the molding material remains accumulated in the heating cylinder 22 of the injection molding machine 1, and the heating cylinder 22 has a high temperature during the molding operation (for example, about 100 ° C., depending on the type of the molding material). State will remain. Further, the mold 5 also remains at the high temperature during the molding operation.

When the above-described abnormality occurs and the molding operation is interrupted, the mold 5 is manually removed from the mold clamping device 2 to remove the molding material retained therein, When the shift cylinder 18 is driven, the heating cylinder 22 and the nozzle 21 thereof need to be separated from the mold 5 to perform a recovery operation such as discharging the molding material remaining in the heating cylinder 22.

When the molding material resin is exposed to a high temperature for a long time, the resin is burnt and carbonized. However, in the above-described conventional automatic injection molding system, particularly when the recovery operation is delayed, the resin remaining in the heating cylinder 22 or the mold 5 may be burned and adhere to the heating cylinder 22 or the mold 5. However, once such adhesion occurs, its recovery is very troublesome. At the time of recovery work, the mold 5 is removed from the mold clamping device 2 as described above. At this time, if the temperature of the mold 5 is high, the cooling temperature by the mold temperature control device 41 is lowered to reduce the temperature of the mold 5. However, it had to wait until it cooled down, and the recovery work could not be performed promptly.

The present invention is intended to solve such a problem, and when a normal molding operation is interrupted due to some abnormality during automatic operation, a recovery operation can be easily and promptly performed. It is an object to provide an automatic injection molding system.

[0014]

In order to achieve the above object, an automatic injection molding system according to the first aspect of the present invention plasticizes a molding material and a molding material for opening and closing a mold, and inserts the molded material into the mold. A molding machine having an injection device for injecting, a material supply device for supplying a molding material to the injection device of the molding machine, and an automatic operation for controlling the molding machine and the material supply device to automatically repeat the molding operation. And a control device for performing, when an abnormality occurs during automatic operation and the normal molding operation is interrupted, the control device stops supplying the molding material from the material supply device to the injection device, After separating the injection device from the mold, the molding material is discharged from the injection device.

During molding by automatic operation, a molding material is supplied from a material supply device to an injection device of a molding machine, the injection device plasticizes the molding material, and a mold clamping device of the molding machine closes the mold. The injection device injects the plasticized molding material into the mold. Further, after the molding material in the mold, that is, the molded product is solidified, the mold clamping device opens the mold and the product is taken out. The above molding cycle is repeated. If any abnormality occurs during such automatic operation, the molding operation is interrupted. At this time, the supply of the molding material from the material supply device to the injection device is stopped, and the injection device is moved to the mold. Is released from the injection device. As a result, the molding material does not stay in the injection device.

According to a second aspect of the present invention, in the automatic injection molding system according to the first aspect of the present invention, the injection device has a plasticizing temperature adjusting means for adjusting the temperature thereof, and the control device operates during the automatic operation. When a normal molding operation is interrupted due to an abnormality, the injection device is kept warm after discharging the molding material from the injection device.

Thus, the molding material slightly remaining in the injection device can be maintained in an appropriate plastic state, and the automatic operation can be restarted immediately after the recovery operation.

According to a third aspect of the present invention, in the automatic injection molding system according to the first or second aspect of the present invention, the automatic injection molding system further includes a mold temperature control device for adjusting the temperature of the mold, and the control device operates abnormally during automatic operation. Occurs and the normal molding operation is interrupted,
This is for cooling the mold.

This makes it possible to remove the mold from the mold clamping device without waiting for the mold to cool down during the recovery work.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the automatic injection molding system according to the present invention will be described below with reference to FIGS. Parts common to the automatic injection molding system shown in FIG. 4 described above are denoted by the same reference numerals, and description thereof is omitted. As shown in FIGS. 1 and 3, the automatic injection molding system includes a mold clamping device 2 for opening and closing a mold 5 and an injection device for plasticizing a molding material such as a thermoplastic resin and injecting the molding material into the mold 5. Injection molding machine 1 which is a molding machine having an injection molding machine 3 and a material supply device for supplying a molding material (eg, pellets) before plasticization to an injection device 3 of the injection molding machine 1
36, a mold temperature controller 41 for adjusting the temperature of the mold 5,
A take-out device 50 for taking out the molded product from the mold 5;
6. A control device 51 is provided for controlling the mold temperature control device 41 and the unloading device 50 and performing an automatic operation for automatically and repeatedly performing a molding operation. The control device 51 may be partially or wholly incorporated in the injection molding machine 1,
It may be provided separately from the injection molding machine 1. However, in order to perform the control described below, particularly when the normal molding operation is interrupted due to occurrence of some abnormality during the automatic operation, at least a signal indicating that the normal molding operation has been interrupted is transmitted to at least the injection molding machine. You need to get from 1. That is, the material supply device 36 and the mold temperature control device 41 are controlled in accordance with the signal from the injection molding machine 1.

Further, the control device 51 controls the injection molding machine 1
, And controls the shift cylinder 18, the injection cylinder 27, and the motor 31 of the injection device 3, respectively. In addition, the injection device 3
Has a plasticizing temperature adjusting means 52 for controlling the power supply to the heater 23 to control the temperature of the heating cylinder 22.The plasticizing temperature adjusting means 52 is also controlled by the controller 51. ing.

When the normal molding operation is interrupted due to some abnormality during the automatic operation, the control device 51 controls the material regardless of the detection state of the sensor 26 provided in the hopper 25 of the injection device 3. The supply of the molding material from the supply device 36 to the hopper 25 is forcibly stopped. Further, the shift cylinder 18 is driven to release the nozzle touch state, that is, the state in which the nozzle 21 of the injection device 3 is pressed against the fixed mold 6 of the mold 5 with a predetermined pressure, and the injection device 3 is moved from the mold 5 Retreat away. Next, the injection cylinder 27 and the motor 31 are driven to discharge the molding material remaining in the heating cylinder 22 of the injection device 3 from the nozzle 21 to a discharge portion 53 such as a tray as shown by an arrow A (automatic purge). ). Further, by controlling the mold temperature control device 41,
The mold 5 is cooled. After the automatic purging, the plasticizing temperature control means 52 of the injection device 3 is controlled to keep the temperature of the heating cylinder 22 warm. The temperature of the heat retention depends on the type of the molding material and the like, but is, for example, about 50 ° C. while the temperature during the molding operation is about 100 ° C.

Next, the operation of the above configuration will be described. At the time of molding by automatic operation, first, the injection device 3 advances to the mold 5 attached to the mold clamping device 2 by driving the shift cylinder 18, and as shown in FIG. Contacts the fixed mold 6. Further, the nozzle 21 is pressed against the fixed mold 6 at a pressure of several tons during the molding operation (nozzle touch).

During the automatic operation, the mold closing device 2 repeats the mold closing and the mold opening, and the injection device 3 repeats the measuring process, the injection process, and the pressure-holding process. In the measuring step, a thermoplastic resin (eg, pellets before plasticization) as a molding material is supplied from the hopper 25 into the heating cylinder 22, and the heating cylinder is heated by the heater 23 and sheared by the rotation of the screw 24. The molding material in 22 is plasticized, and the plasticized molding material is stored in the heating cylinder 22 on the nozzle 21 side (front side). At this time, the screw 24 retreats away from the mold 5. Then, after the fixed mold 6 and the movable mold 7 are closed, and a predetermined amount of molding material is accumulated in the front portion in the heating cylinder 22, the injection cylinder 27 is driven to rotate the screw.
24 advances to the mold 5 side, and the molding material in the heating cylinder 22 is injected from the nozzle 21 into the mold 5 (injection step). Thereafter, the pressure is held by the back pressure applied from the injection cylinder 27 to the screw 24 (pressure holding step). Further, the molding material in the mold 5, that is, the molded product is sufficiently cooled and solidified (cooling step). Thereafter, the fixed mold 6 and the movable mold 7 are opened, and the molded product is taken out by the unloading device 50. Taken out. On the other hand, in the injection device 1, the measuring process is started again, and the above molding cycle is repeated.

When the sensor 26 detects that the molding material in the hopper 25 has decreased below the level of the sensor 26, the molding material is automatically replenished from the material supply device 36 into the hopper 25, and the hopper 25 is refilled. The molding material in the sensor 26
Is reached, the supply of the molding material from the material supply device 36 to the hopper 25 is stopped.

In the automatic operation as described above, if any abnormality such as a failure of the apparatus occurs, the injection molding machine 1 interrupts the normal molding operation (step 61 in FIG. 2), and at the same time, operates the buzzer and lamp. An alarm is issued by the alarm means 46. At this time, the control device 51 receives a signal from the injection molding machine 1 and the control device 51 also stops the operation of the unloading device 50. Before the stop, a product molded in the mold 5 remains. If this product can be removed,
Causes the take-out device 50 to take out the product. Therefore,
If the normal molding operation is interrupted due to the occurrence of an abnormality,
Basically, the fixed mold 6 and the movable mold 7 of the mold 5 are opened.

Then, the control device 51 forcibly stops the supply of the molding material from the material supply device 36 to the hopper 25 irrespective of the detection state of the sensor 26 (step 62 in FIG. 2). Further, the shift cylinder 18 is driven to release the nozzle touch state, that is, the state in which the nozzle 21 of the injection device 3 is pressed against the fixed mold 6 of the mold 5 with a predetermined pressure, and the injection device 3 is moved from the mold 5 It is retracted in the direction away (step 63 in FIG. 2). Then, injection cylinder 27 and motor 31
To discharge the molding material remaining in the heating cylinder 22 of the injection device 3 from the nozzle 21 to the discharge portion 53 (step 64 in FIG. 2). Thus, the molding material hardly stays in the heating cylinder 22 of the injection device 3. Further, thereafter, the heating cylinder 22 is kept warm by the plasticizing temperature adjusting means 52 (step 65 in FIG. 2). The temperature of the heat retention depends on the type of the molding material and the like, but is, for example, about 50 ° C. while the temperature during the molding operation is about 100 ° C. Further, the mold 5 is cooled by the mold temperature adjusting device 41 (Step 66 in FIG. 2). Although the cooling temperature depends on the type of molding material, for example, the temperature during the molding operation is 100 ° C.
About 50 ° C.

According to the configuration of the above embodiment, when any abnormality occurs during the automatic operation and the normal molding operation is interrupted, the supply of the molding material from the material supply device 36 to the injection device 3 is stopped. After the injection device 3 is separated from the mold 5, the molding material is discharged from the injection device 3 (automatic purge).
Therefore, it is possible to prevent the resin which is the molding material staying in the heating cylinder 22 of the injection device 3 from burning or carbonizing and adhering to the inside of the heating cylinder 22. Therefore, there is no need to treat the resin seized in the heating cylinder 22, so that the recovery operation can be easily and promptly performed. Note that the automatic purging itself could be performed by a conventional injection molding machine, but conventionally, it had to be performed by operating the control panel 33. On the other hand, in the automatic injection molding system, automatic purging is automatically performed when the normal molding operation is interrupted due to occurrence of an abnormality.

Further, since the heating cylinder 22 of the injection device 3 is kept warm after the automatic purging, the molding material slightly remaining in the heating cylinder 22 can be maintained in an appropriate plastic state that does not cause burning. Automatic operation can be promptly restarted.

Further, since the mold 5 is cooled, the mold 5 can be fixed to the mold clamping device 2 without waiting for cooling of the mold 5 during recovery work.
, So that the restoration work can be performed more quickly.

The present invention is not limited to the above-described embodiment, and various modifications can be made. For example,
In the above-described embodiment, when an abnormality occurs during the automatic operation and the normal molding operation is interrupted, then the heating cylinder 22 is kept warm and the mold 5 is cooled, but this is not essential. For example, in the case of a temporary interruption due to a slight failure, a considerable effect can be obtained even if only the automatic purging is performed. Further, in the above embodiment, the in-line screw type injection molding machine 1 has been described as an example.
Such as plunger or pre-plastic injection molding machines
Applicable to various molding machines. Further, the present invention is applicable not only to injection molding of a thermoplastic resin but also to injection molding of other molding materials.

[0032]

According to the automatic injection molding system of the first aspect of the present invention, when an abnormality occurs during the automatic operation and the normal molding operation is interrupted, the supply of the molding material from the material supply device to the injection device is performed. The injection material is ejected from the injection device after the injection device is released from the mold, and when the normal molding operation is interrupted due to any abnormality during automatic operation, the recovery operation can be easily and promptly performed. It can be carried out.

According to the automatic injection molding system of the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, when an abnormality occurs during the automatic operation and the normal molding operation is interrupted, the injection device performs the molding operation. Since the injection device is kept warm after discharging the material, it is possible to resume the automatic operation promptly after the recovery operation by keeping the molding material slightly remaining in the injection device in an appropriate plastic state.

According to the automatic injection molding system of the third aspect, in addition to the effects of the first or second aspect, when an abnormal condition occurs during automatic operation and normal molding operation is interrupted, the die Is cooled, the mold can be removed from the mold clamping device without waiting for the mold to cool down during the recovery work, and the recovery work can be performed more quickly.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of an automatic injection molding system of the present invention.

FIG. 2 is a process diagram of the same.

FIG. 3 is a schematic side view in which a part of the above is sectioned, and shows a state when an abnormality occurs.

FIG. 4 is a schematic side view in which a part of the above is sectioned, and shows a state during normal molding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Injection molding machine (molding machine) 2 Mold clamping device 3 Injection device 5 Mold 36 Material supply device 41 Mold temperature control device 51 Control device 52 Plasticization temperature control means

Claims (3)

[Claims] 1. A molding machine having a mold clamping device for opening and closing a mold, an injection device for plasticizing the molding material and injecting the molding material into the mold, and a material supply for supplying the molding material to the injection device of the molding machine. And a control device for controlling the molding machine and the material supply device to perform an automatic operation for automatically and repeatedly performing the molding operation. When the operation is interrupted, the supply of the molding material from the material supply device to the injection device is stopped, and after the injection device is separated from the mold, the molding material is discharged from the injection device. Automatic injection molding system. 2. The injection device has a plasticizing temperature adjusting means for adjusting a temperature of the injection device, and the control device is configured to control the injection device when a normal molding operation is interrupted due to an abnormality during automatic operation. 2. The automatic injection molding system according to claim 1, wherein the injection device is kept warm after the molding material is discharged from the mold. 3. A mold temperature control device for adjusting a temperature of the mold, wherein the control device cools the mold when an abnormality occurs during automatic operation and normal molding operation is interrupted. 3. The automatic injection molding system according to claim 1, wherein: