JP2012135912A - Injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection molding machine capable of restarting molding operation automatically which has been stopped due to the occurrence of a power failure at the recovery of the power failure.SOLUTION: The injection molding machine is provided with a power storage device 23 storing power usable during the power failure and is provided with a restoring operation necessity determination part 212 for determining the necessity of the restoring operation for restarting the molding operation stopped due to the occurrence of the power failure at the recovery of the power failure. The restoring operation necessity determination part 212 controls to automatically restart the molding operation stopped by the occurrence of the power failure without an operation input by an operator when it is determined that the restoring operation is not necessary.

Description

  The present invention relates to an injection molding machine including a power storage device that stores power that can be used when a power failure occurs in an AC power supply.

  Conventionally, an injection molding machine including a storage battery that stores electric power generated by a solar panel is known (see, for example, Patent Document 1).

  This injection molding machine includes a main control device driven by a commercial AC power source and a sub-control device driven by the storage battery, and records control data of the main control device in a memory in the sub-control device in real time. In addition, while maintaining the control data even when a power failure occurs, the contents of the control data recorded in the memory (ie, the situation at the time of the power failure) can be displayed on the CRT when the power failure is resolved. It is possible to assist the operator to restart the injection molding machine stopped due to the occurrence.

  In addition to the contents of the control data recorded in the memory, when the power failure is resolved, the injection molding machine performs a restoration operation according to the contents of the control data (for returning the injection molding machine to a restartable state). The manual operation procedure can be displayed on the CRT.

  Furthermore, in the event that a power failure occurs while the mold with a core insertion / removal device is still clamped, this injection molding machine returns the mold to the home position where mold opening has been completed when the power failure is resolved. Therefore, the core operation after mold opening is completed is automatically executed.

  Also, this injection molding machine loses power when melt plasticized resin remains in the injection cylinder, and when the resin is cooled and solidified by stopping heating by the heater for the injection cylinder, the power failure occurs. At the time of cancellation, turn on the cold start prevention relay of the screw, turn on the power of the injection cylinder heater, remelt the residual resin, turn off the cold start prevention relay of the screw, and perform the injection process by purging By discharging the residual resin inside, a new resin can be filled.

JP 2000-202886 A

  However, Cited Document 1 discloses that a predetermined restoration operation is performed when the power failure is resolved, such as when a power failure occurs while the mold is still clamped, or when a power failure occurs when molten plastic remains in the injection cylinder. It is only disclosed the process when the injection molding machine cannot be restarted without performing the process, and the process when restarting the injection molding machine without performing a restoration operation when the power failure is resolved is disclosed. Absent.

  In view of the above-described points, an object of the present invention is to provide an injection molding machine that can automatically restart a molding operation stopped due to the occurrence of a power failure when the power failure is resolved.

  In order to achieve the above object, an injection molding machine according to an embodiment of the present invention is an injection molding machine including a power storage device that stores electric power that can be used during a power failure. A restoration operation necessity determination unit that determines whether restoration operation for resuming the stopped molding operation is required is provided.

  With the above-described means, the present invention can provide an injection molding machine that can automatically restart a molding operation stopped due to the occurrence of a power failure when the power failure is resolved.

It is the schematic which shows the structural example of the molding control system mounted in the injection molding machine which concerns on the Example of this invention. It is a functional block diagram which shows the structural example of the controller in a control part. It is a flowchart which shows the flow of a control process at the time of a power failure.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic diagram illustrating a configuration example of a molding control system SYS mounted on an injection molding machine according to an embodiment of the present invention, and FIG. 2 is a functional block diagram illustrating a configuration example of a controller 21 in a control unit 20. It is.

  The molding control system SYS is a system for controlling the molding operation of the injection molding machine, and mainly includes an AC power source 10, a control unit 20, a power conversion unit 30, an electric motor 40, a molding machine sensor 50, and a peripheral device sensor 51. , A display device 60, and an audio output device 61.

  The AC power source 10 is a device for supplying AC power to the control unit 20 and the power conversion unit 30, and is, for example, a commercial three-phase AC power source.

  The control unit 20 is a device for controlling the molding operation of the injection molding machine, and mainly includes a controller 21, a switching power supply 22, a power storage device 23, and an AC voltage detection circuit 24.

  The controller 21 is a computer including a CPU (Central Processing Unit), a RAM (Random Access Memory), an SRAM (Static RAM), a flash memory, a ROM, and the like. For example, the molding control unit 210, the power failure determination unit 211, and the restoration A program corresponding to each functional element of the operation necessity determination unit 212, the restoration operation support unit 213, and the control continuity determination unit 214 (see FIG. 2) at the time of a power failure is read from the ROM and expanded on the RAM. The CPU is caused to execute processing corresponding to the above.

  Each functional element may be configured by hardware using an analog circuit, a digital circuit, a PLD (Programmable Logic Device), an FPGA (Field Programmable Gate Array), an FPAA (Field Programmable Analog Array), or the like.

  In addition, the controller 21 acquires detection values output from the power storage device 23, the molding machine sensor 50, the peripheral device sensor 51, and the like, executes processing corresponding to each of the functional elements described above, and according to the processing result. The control signal is output to the display device 60 and the audio output device 61.

  Further, the controller 21 monitors the rotation speed value of the electric motor 40 output from an encoder (not shown) attached to the rotation shaft of the electric motor 40 and includes a command value of a desired motor rotation speed. A control signal is generated, and the generated timing control signal is output to the inverter circuit 34 that drives the electric motor 40.

  The switching power supply 22 is a device that converts AC power of the AC power supply 10 into DC power. For example, the switching power supply 22 converts AC power having a predetermined voltage into DC power having a predetermined voltage.

  The power storage device 23 is a device for supplying the DC power to the controller 21 while storing the DC power output from the switching power supply 22. For example, the supply of AC power from the AC power supply 10 is interrupted, and the switching power supply Even when the supply of DC power from 22 is interrupted, DC power of a predetermined voltage can be continuously supplied to the controller 21 over a certain period.

  Further, the power storage device 23 may output information related to a power storage state such as a power storage voltage to the controller 21 so that the controller 21 can monitor and grasp the power storage state of the power storage device 23.

  The AC voltage detection circuit 24 is a device for detecting the AC voltage supplied to the switching power supply 22. For example, by outputting the detection result to the controller 21, whether or not a power failure has occurred in the AC power supply 10 is detected. The controller 21 can be detected. Note that the AC voltage detection circuit 24 may be replaced with a device for detecting a DC voltage supplied to the power storage device 23.

  The power conversion unit 30 is an apparatus for converting AC power into DC power and further converting the DC power into AC power suitable for various loads, for example, an inverter mounted on an injection molding machine, A diode module 31, a capacitor 32, and an inverter circuit 34 are provided.

  The diode module 31 is a device that converts AC power of the AC power supply 10 into DC power. For example, the diode module 31 converts AC power having a predetermined voltage into DC power having a predetermined voltage.

  The capacitor 32 is a device for smoothing the output of the diode module 31, and is, for example, an electrolytic capacitor.

  The inverter circuit 34 is a device for converting DC power into AC power. For example, power switching such as an IGBT (Insulated Gate Bipolar Transistor), an IPM (Intelligent Power Module), or a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The power switching element is turned on / off in accordance with a timing control signal from the controller 21 in the control unit 20 to convert DC power into AC power.

  The electric motor 40 is an electric load that operates by receiving AC power. For example, the electric motor 40 is a closed-loop control servomotor, and an injection motor and mold clamping when the power conversion unit 30 is mounted on an injection molding machine. Motors, resin metering motors, ejector motors, and the like.

  In FIG. 1, the molding control system SYS is illustrated as including only one combination of the power conversion unit 30 and the electric load (electric motor 40), but another combination (for example, the power conversion unit 30). And a combination of an injection cylinder heater and the like.

  The molding machine sensor 50 is a sensor for detecting the operating state of the injection molding machine main body. For example, the molding machine sensor 50 detects the rotational states of the injection motor, mold clamping motor, resin metering motor, and ejector motor. To detect the pressure in the injection cylinder, the encoder attached to the drive shaft of each motor, the strain sensor for detecting the back pressure of the injection screw, the temperature sensor for detecting the temperature in the injection cylinder The detected value is output to the controller 21.

  The peripheral device sensor 51 is a sensor for detecting the operating state of the peripheral device attached to the injection molding machine. For example, a feeder for supplying resin pellets to the injection cylinder or an injection cylinder for heating the injection cylinder It is a sensor that detects the operating state of a heater or the like, and outputs the detected value to the controller 21.

  The display device 60 is a device for displaying various types of information. For example, the display device 60 is a liquid crystal display or an LED (Light Emitting Diode) and the like. ), Information related to the molding operation of the injection molding machine, such as the restart of the molding operation or the content of the restoration operation.

  The voice output device 61 is a device for outputting various information as voices. For example, the voice output device 61 is a speaker or a buzzer, which generates a power failure, eliminates the power failure (starts power supply by an emergency AC backup power source), and performs a molding operation. Information related to the molding operation of the injection molding machine such as the contents of the restart or restoration operation is notified.

  Next, each functional element included in the controller 21 will be described.

  The molding control unit 210 is a functional element for controlling the molding operation of the injection molding machine. For example, one or a plurality of electric motors 40 (for example, an injection motor) are controlled in accordance with outputs from the molding machine sensor 50 and the peripheral device sensor 51. A timing control signal for each of the inverter circuits 34 corresponding to each of the motor, mold clamping motor, resin metering motor, ejector motor, etc.), and each of the one or a plurality of inverter circuits 34 is generated. The generated timing control signals are output.

  In addition, the molding control unit 210 is configured to output one or a plurality of peripheral devices (for example, an ejector, a resin supply feeder, a mold heater, an injection cylinder heater, etc.) according to the outputs of the molding machine sensor 50 and the peripheral device sensor 51. And may be a device driven by a power source different from that of the injection molding machine, or may be a device driven by the same power source as the injection molding machine). Alternatively, the generated control signals are output to a plurality of peripheral devices.

  The molding control unit 210 records the output of the molding machine sensor 50 and the peripheral device sensor 51 received at a predetermined sampling interval in the RAM in a time series as a part of log information, and changes the molding operation of the injection molding machine. Enable post-mortem analysis.

  The power failure determination unit 211 is a functional element for determining whether or not the supply of AC power to the control unit 20 or the power conversion unit 30 is interrupted. For example, based on the output of the AC voltage detection circuit 24, the AC power supply 10 The presence or absence of the occurrence of a power failure (including instantaneous power failure) and the presence or absence of a power failure in the AC power source 10 (for example, the start of power supply by the emergency AC backup power source) are determined.

  The restoration operation necessity determination unit 212 is a functional element for determining whether or not a restoration operation (manual operation) for resuming the molding operation of the injection molding machine stopped due to the occurrence of the power failure when the power failure is resolved. When incomplete filling of the resin in the mold is detected based on the output of the molding machine sensor 50, it is determined that a restoration operation is necessary.

  When the cavity in the mold is completely filled with resin, the injection molding machine automatically moves the molded product derived from the resin out of the mold (as a defective product) by automatically operating the ejector. Although it can be discharged, if the cavity in the mold is incompletely filled with resin, it may not be possible to discharge an incomplete molded product derived from that resin simply by automatically operating the ejector. Because there is. Note that the restoration operation required in this case is discharge of a molded product derived from the incompletely filled resin out of the mold.

  The restoration operation necessity determination unit 212 determines that the restoration operation is necessary when the elapsed time from the occurrence of the power failure exceeds a predetermined time.

  Due to the stop of the heater for the injection cylinder for a predetermined time due to the occurrence of a power failure, the resin temperature in the injection cylinder decreases and the resin changes in quality, or due to the stop of the heater for the mold for a predetermined time due to the occurrence of a power failure This is because the mold temperature may be lowered and the mold may be deformed. The restoration operation required in this case is heating to the set temperature of the injection cylinder by the heater for the injection cylinder, or heating to the set temperature of the mold by the heater for the mold.

  Further, the restoration operation necessity determination unit 212 detects that one or more peripheral devices are in an inoperable state based on the output of the peripheral device sensor 51, or from the one or more peripheral device sensors 51. When the output cannot be received, it is determined that the restoration operation is necessary.

  This is to prevent the molding operation from being restarted without confirming the normal operating state of the peripheral device. The restoration operation required in this case is to operate the peripheral device normally.

  On the other hand, when it is determined that the restoration operation is unnecessary, the restoration operation necessity determination unit 212 automatically restarts the molding operation without obtaining an operation input by the operator. In this case, the restoration operation necessity determination unit 212 may restart not only the main body of the injection molding machine but also peripheral devices.

  In addition, when the restoration operation necessity determination unit 212 determines that the restoration operation is unnecessary, the restoration operation may be resumed after obtaining confirmation from the operator.

  Specifically, the restoration operation necessity determination unit 212 is a screen for prompting confirmation by the operator (for example, a text message that prompts the user to press a confirmation button (not shown) for confirming resumption of the molding operation). Is displayed on the display device 60, and the molding operation is resumed when the confirmation button is pressed.

  The restoration operation necessity determination unit 212 displays the screen for prompting confirmation by the operator, and when confirmation by the operator is not obtained even after a predetermined time has elapsed, confirmation by the operator is performed. The molding operation may be resumed without obtaining it. This is in order to avoid the elapsed time from the occurrence of a power failure exceeding a predetermined time and requiring a restoration operation.

  On the other hand, the restoration operation necessity determination unit 212 is a case where confirmation by the operator is not obtained even after displaying a screen for prompting confirmation by the operator, and the elapsed time from the occurrence of the power failure is a predetermined time. If it exceeds the limit, it may be determined that a restoration operation is necessary again, and automatic restart of the molding operation may be prohibited.

  Further, the restoration operation necessity determination unit 212 may cause the display device 60 to display that the molding operation has been automatically resumed, and may cause the audio output device 61 to output the sound. In addition, information indicating that may be added to the log information.

  The restoration operation support unit 213 is a functional element for assisting the execution of the restoration operation by the operator when the restoration operation necessity determination unit 212 determines that the restoration operation is necessary. For example, a molding machine sensor 50 or the output of the peripheral device sensor 51, one or more necessary restoration operations are determined, and the contents and execution order of the determined restoration operations are displayed on the display device 60, or the contents and execution order are determined. The audio output device 61 outputs audio.

  Also, the restoration operation support unit 213 prevents an operation other than the determined restoration operation from being performed, or prevents the determined restoration operation from being performed in an order other than the determined execution order. An interlock may be set.

  Further, the restoration operation support unit 213 may automatically execute the purge process when the elapsed time from the occurrence of the power failure exceeds a predetermined time. Specifically, the restoration operation support unit 213 heats the injection cylinder to the set temperature with the heater for the injection cylinder, supplies new resin pellets into the injection cylinder, and remains in the injection cylinder. Is discharged out of the injection cylinder.

  Also, the restoration operation support unit 213 detects that one or more peripheral devices are in an inoperable state based on the output of the peripheral device sensor 51, or outputs the output from the one or more peripheral device sensors 51. If reception is not possible, the peripheral device may be reset by outputting a reset signal to the one or more peripheral devices.

  The power failure control continuation determination unit 214 is a functional element for determining whether or not the power failure control process of the controller 21 by the power stored in the power storage device 23 can be continued. For example, the power storage device 23 Whether or not the control process during power failure by the controller 21 can be continued is determined based on the stored voltage.

  Specifically, the power failure control continuation determination unit 214 causes the controller 21 to continue the power failure control process when the power storage voltage of the power storage device 23 is equal to or higher than a predetermined voltage. When the voltage falls below a predetermined voltage, the controller 21 performs a shutdown process to stop the power failure control process by the controller 21.

  Note that the “shutdown process” means, for example, that data necessary for various data processing executed by the CPU is saved in a nonvolatile storage medium such as SRAM or flash memory in preparation for the restart of the controller 21, It means a process of completely stopping the power supply to the controller 21 after the data processing is finished.

  Next, the flow of power failure control processing by the molding control system SYS will be described with reference to FIG. FIG. 3 is a flowchart showing the flow of the power failure control process. The molding control system SYS repeatedly executes the power failure control process at a predetermined cycle until the controller 21 is completely stopped by the shutdown process. Shall.

  First, the controller 21 of the control unit 20 determines whether or not a power failure has occurred by the power failure determination unit 211 based on the output of the AC voltage detection circuit 24 (step S1).

  If it is determined that a power failure has not occurred (NO in step S1), the controller 21 ends the current power failure control process.

  When it is determined that a power failure has occurred (YES in step S1), the controller 21 outputs a control signal to the display device 60 and the sound output device 61 to display or sound output that the power failure has occurred. This is notified to the person (step S2).

  When a power failure occurs (when supply of AC power from the AC power supply 10 is interrupted), the injection molding machine automatically changes the operation of the controller 21 by the AC power to the operation of the controller 21 by the power stored in the power storage device 23. The operation of components other than the controller 21 such as the electric motor 40 is stopped.

  Thereafter, the controller 21 uses the power failure determination unit 211 to determine whether or not the power failure has been resolved based on the output of the AC voltage detection circuit 24 (step S3).

  When it is determined that the power failure has been resolved (YES in step S3), the controller 21 determines whether the restoration operation for resuming the molding operation can be omitted by the restoration operation necessity determination unit 212 ( Step S4).

  If it is determined that the restoration operation can be omitted (YES in step S4), the controller 21 automatically restarts the molding operation without requiring an operation input by the operator (step S5), and this time Terminate control processing during power failure.

  On the other hand, when it is determined that the restoration operation cannot be omitted (NO in step S4), the controller 21 causes the restoration operation support unit 213 to display the contents and execution order of the restoration operation necessary for resuming the molding operation. It is displayed on the device 60 (step S6). Note that the controller 21 may display only the content of the restoration operation necessary to restart the molding operation.

  Further, the controller 21 prevents the restoration operation support unit 213 from performing an operation other than the determined restoration operation and prevents the restoration operation from being performed in an order other than the determined execution order. An interlock is set (step S7).

  As described above, the controller 21 ends the current power failure control process after displaying the information related to the restoration operation and setting the interlock. It should be noted that the display of the information related to the restoration operation and the setting of the interlock may be performed simultaneously, or the information related to the restoration operation may be displayed after the setting of the interlock.

  When it is determined in step S3 that the power failure has not been resolved (YES in step S3), the controller 21 controls the controller 21 during power failure by the power stored in the power storage device 23 by the control continuity determination unit 214 during power failure. It is determined whether the process can be continued (step S8).

  When it is determined that the control process during a power failure of the controller 21 by the power stored in the power storage device 23 can be continued because the power storage voltage of the power storage device 23 is equal to or higher than the predetermined voltage (YES in step S8), the controller 21 It returns to step S3 and the presence or absence of a power failure cancellation is determined.

  On the other hand, when it is determined that the power failure control process of the controller 21 by the power stored in the power storage device 23 cannot be continued because the power storage voltage of the power storage device 23 is lower than the predetermined voltage (NO in step S8), the controller 21 Then, the shutdown process is executed (step S9), and the power failure control process is terminated.

  With the above configuration, the injection molding machine equipped with the molding control system SYS has the power storage device 23 that stores power that can be used during a power failure, so that the power stored in the power storage device 23 can be stored even during a power failure. Thus, the controller 21 can execute the control process at the time of power failure, and the molding operation stopped due to the occurrence of the power failure can be automatically restarted when the power failure is resolved.

  Further, the injection molding machine equipped with the molding control system SYS determines whether or not a restoration operation for resuming the molding operation is necessary based on the outputs of the molding machine sensor 50 and the peripheral device sensor 51, and determines that the restoration operation is unnecessary. In this case, the molding operation stopped due to the occurrence of a power failure is automatically restarted without any operation input by the operator, so the burden on the operator when resuming the molding operation (judgment of necessity of restoration operation, proper order) For example, performing a restoration operation according to the above).

  In addition, when it is determined that the restoration operation is unnecessary, the injection molding machine equipped with the molding control system SYS urges confirmation by the operator to resume the molding operation, and performs the molding operation after obtaining confirmation from the operator. Since it is resumed, it is possible to reduce the time required to resume the molding operation while preventing the molding operation from being resumed against the operator's intention.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, even when the molding control system SYS determines that the restoration operation necessity determination unit 212 cannot omit the restoration operation for resuming the molding operation, the restoration operation is performed. Depending on the contents, the restoration operation may be automatically executed without obtaining an operation input by the operator, and the molding operation may be resumed without obtaining the operation input by the operator.

  DESCRIPTION OF SYMBOLS 10 ... AC power supply 20 ... Control part 21 ... Controller 22 ... Switching power supply 23 ... Power storage device 24 ... AC voltage detection circuit 30 ... Power conversion part 31 ... Diode module 32 ... Capacitor 34 ... Inverter circuit 40 ... Electric motor 50 ... Molding machine sensor 51 ... Peripheral device sensor 60 ... Display device 61 ... Audio output device 210 ... Molding control Unit 211 ... Power failure determination unit 212 ... Restoration operation necessity judgment unit 213 ... Restoration operation support unit 214 ... Power failure control continuity judgment unit SYS ... Molding control system

Claims (3)

An injection molding machine equipped with a power storage device that stores power that can be used during a power failure,
When a power failure is eliminated, a restoration operation necessity determination unit for judging whether or not a restoration operation for resuming a molding operation stopped due to the occurrence of a power failure is provided.
An injection molding machine characterized by that. When the restoration operation necessity determination unit determines that the restoration operation is unnecessary, the molding operation stopped due to the occurrence of a power failure is automatically restarted without an operation input by the operator.
The injection molding machine according to claim 1. When it is determined that the restoration operation is unnecessary, the restoration operation necessity determination unit prompts confirmation by the operator for resuming the molding operation, and restarts the molding operation after obtaining confirmation by the operator.
The injection molding machine according to claim 1.

Images