JP2009241535A - Multi-shaft mechanical device and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-shaft mechanical device which makes effective use of a regenerative power by reducing a loss of the regenerative power as much as possible than before. <P>SOLUTION: A connection switching circuit 11 for switching a connection between each of motor control circuits 1 to 3 and a power source 10 so that when at least one drive motor is in a regenerative state, the regenerative power is used as a driving power of at least one power-running drive motor of other drive motors is disposed between the power source 10 and the motor control circuits 1 to 3. An operation timing output part 6 outputs an operation timing constituted so as to include an overlapping period where at least one power-running drive motor of other drive motors is in an acceleration state, when at least one drive motor is in the regenerative state. The connection switching circuit 11 performs the switching operation so as to supply, as a load current, a regenerative current generated by the regenerative drive motor to the power-running drive motor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a multi-axis mechanical device that controls a plurality of drive motors that drive a plurality of shafts according to set operation timings, a control method therefor, and a molded product take-out machine.

Japanese Patent Laid-Open No. 2000-141440 (Patent Document 1) stores regenerative power generated during a deceleration period of a motor as a drive source in a power storage unit, and stores power (charge) stored in the power storage unit during a motor acceleration period. A motor driving device of an injection molding machine that discharges as a part of motor driving power is disclosed.
JP 2000-141440 A

  Conventionally, when a plurality of shafts such as the X-axis, Y-axis, and Z-axis are moved by a plurality of drive motors like a molded product take-out machine, the power stored in the power storage means as part of the drive power of the drive motor It is conceivable to use (charge). However, in both the process of storing power in the power storage means and the process of discharging charges from the power storage means, the regenerative power is lost as a resistance loss. Therefore, when using the energy from the power storage means, it cannot be said that the regenerative power is always effectively utilized.

  An object of the present invention is to provide a multi-axis machine apparatus and a control method thereof that can reduce the loss of regenerative power as much as possible and can effectively use the regenerative power as compared with the conventional art.

  A specific object of the present invention is to provide a molded product take-out machine that can reduce the loss of regenerative power as much as possible and can use the regenerative power more effectively than in the past.

  The present invention is directed to a control method for a multi-axis mechanical device that controls a plurality of drive motors that drive a plurality of axes in accordance with set operation timings. In the method of the present invention, the operation timing is configured to include a superposition period in which at least one of the driving motors is in the acceleration state in the power running state when the at least one driving motor is in the regenerative state. In the polymerization period, the regenerative current generated by the drive motor in the regenerative state is supplied as a load current (effective current) to the drive motor in the power running state. That is, the regenerative current is directly supplied to the other driving motor in the acceleration state, and a part of the regenerative current is used to drive the other driving motor. Therefore, according to the present invention, it is possible to effectively use the regenerative power while minimizing the loss of the regenerative power. In particular, in the present invention, since the regenerative current is used at the time of acceleration, there is no significant influence on the rotational operation of other drive motors that are supplied with the regenerative current.

  Note that the power storage means is charged using regenerative power generated by one or more drive motors in a regenerative state outside the polymerization period. In this way, regenerative power that is not used for driving other drive motors can be effectively used without consuming it as heat.

  A multi-axis mechanical device of the present invention that implements the method of the present invention includes a plurality of drive motors that drive a plurality of axes, a plurality of motor control circuits that respectively control the plurality of drive motors based on operation timing, An operation timing output unit that stores the set operation timing in a storage unit and outputs the operation timing to a plurality of motor control circuits. In the multi-axis mechanical device of the present invention, when at least one drive motor is in the regenerative state between the power source and the plurality of motor control circuits, the drive motor is driven in at least one other power running state. A connection relationship switching circuit is provided for switching the connection relationship between the plurality of motor control circuits and the power source so as to use regenerative power as power. The operation timing is configured to include a superposition period in which at least one other drive motor is in the acceleration state in the power running state when at least one drive motor is in the regenerative state. The connection relation switching circuit performs a switching operation so as to supply a regenerative current generated by the driving motor in the regenerative state as a load current to the driving motor in the power running state during the polymerization period. The connection relationship switching circuit can be configured using a plurality of semiconductor switching elements.

  In addition, you may further provide the electrical storage means and the charging circuit which charges an electrical storage means using regenerative electric power. When using these means, the connection relationship switching circuit uses the regenerative power generated by one or more drive motors in a regenerative state other than during the polymerization period so that the charging circuit charges the power storage means. And a plurality of motor control circuits. If it does in this way, regenerative electric power can be used effectively. For example, the power storage unit may be used as at least a driving power source for the operation timing output unit. Of course, the present invention can be applied to a molded product take-out machine including a plurality of motors for taking out a molded product.

  According to the present invention, it is possible to effectively use the regenerative power while minimizing the loss of the regenerative power. In particular, since the regenerative current is used during acceleration, the operation of the other drive motor that receives the regenerative current is used. The advantage is that there is no significant effect on the system.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram schematically showing a configuration of a main part of an operation control circuit of a molded product take-out machine as a specific example of the multi-axis machine device of the present invention that implements the method of the present invention. FIG. 2 is a diagram showing a part of the operation timing. Before explaining the circuit configuration of FIG. 1, an example of the hardware configuration of a molded product take-out machine A to which the present invention is applied will be described with reference to FIG. 3. FIG. 3 shows a perspective view of a molded product take-out machine A called a “traverse” type. An article take-out machine A called a “traverse” type is generally placed on a molding machine fixing plate (not shown) and is capable of moving forward and backward in the XYZ three-axis directions, an X driving motor Mx, a Y axis driving motor My and Z A shaft driving motor Mz is provided. Further, the molded product take-out machine A includes a molded product gripping part that takes out the molded product from the molding machine (mold) by clamping or suction. The molded product take-out machine A takes out the molded product in conjunction with a predetermined molding operation of the molding machine, then transfers the molded product to a predetermined position, opens it, moves to the standby position, waits at the standby position, and takes out. By repeating the predetermined operation, automatic operation is performed in conjunction with the molding machine. The part names of the devices that enable the X, Y, and Z axes to move forward and backward are called the traversing part, the drawing part, and the lifting part. FIG. 3 shows one having two lifting parts. In this molded product take-out machine A, the X-axis drive is used as a power source for linearly moving the drawing frame C (drawing unit, elevating unit) along the horizontal frame B constituting the horizontal unit of the molded product taking-out machine A. Drive control of the motor Mx is performed. One end portion in the transverse frame B (the end portion on the X-axis drive motor Mx side) is rotated by the X-axis drive motor Mx via a gear mechanism housed in the gear box D. A pulley is installed, and another pulley that enables an endless timing belt E to be stretched is provided at the other end in the transverse frame B. The timing belt E is rotated in the transverse frame B by using the transverse servomotor M as a drive source. The extraction portion of the extraction frame C to which a part of the timing belt E is attached and fixed is configured to be able to reciprocate back and forth (linearly) by the linear motion guide mechanism in the transverse frame B. A servo amplifier (X-axis motor control circuit 1 in FIG. 1) of the X-axis drive motor Mx is arranged in a control box labeled F. The product-side elevator G and the runner-side elevator H are also equipped with a pulling servo motor (Y-axis driving motor My) and a lifting servo motor (Z-axis driving motor Mz), respectively. Servo amplifiers (Y-axis motor control circuit 2 and Z-axis motor control circuit 3 in FIG. 1) for these servo motors (Y-axis drive motor My and Z-axis drive motor Mz in FIG. 1) are provided in control box I. It is stored. Further, although not shown, the molded product take-out machine A is attached with a molded product gripping device, and in this molded product gripping device, air adsorption or air gripping of the molded product is executed by controlling an air valve. .

  As shown in FIG. 1, an X-axis motor control circuit 1 that controls the drive of the aforementioned X-axis drive motor Mx, a Y-axis motor control circuit 2 that controls the drive of the Y-axis drive motor My, and a Z-axis drive motor The Z-axis motor control circuit 3 that controls the drive of Mz controls each motor based on the operation timing output from the operation timing output unit 6 constituted by the CPU 5 in the control unit 4. The CPU 5 realizes the operation timing output unit 6 by an operation program stored in the first memory 7. The operation timing output unit 6 outputs the operation timing based on the operation timing data stored in the second memory 8 (storage unit) by the input from the controller 9.

  In the present embodiment, at least one drive motor (Mx, My or Mz) is in a regenerative state between the power supply 10 and the X-axis motor control circuit 1, the Y-axis motor control circuit 2, and the Z-axis motor control circuit 3. The X-axis motor control circuit 1, the Y-axis motor control circuit 2, and the like so that the regenerative power is used as drive power for the drive motor (Mx, My or Mz) in at least one other power running state. A connection relationship switching circuit 11 for switching the connection relationship between the Z-axis motor control circuits 3 is provided. The power conversion circuit included in the power source 10, the X-axis motor control circuit 1, the Y-axis motor control circuit 2, and the Z-axis motor control circuit 3 is configured to regenerate regenerative power.

  The operation timing output from the operation timing output unit 6 is a polymerization period (the regeneration state and the power running) in which the at least one drive motor is in the regenerative state and the other at least one drive motor is in the acceleration state in the power running state. The period in which the acceleration state in the state overlaps) is included. The connection relation switching circuit 11 loads the regenerative current generated by the drive motor in the regenerative state to the drive motor in the power running state during the above-described polymerization period based on the operation timing output from the operation timing output unit 6. The switching operation is performed so that the current (effective current) is supplied. The specific circuit configuration of the connection relationship switching circuit 11 is arbitrary. For example, it can be configured using a plurality of power semiconductor switching elements.

  FIG. 2 shows operation timings of the X-axis drive motor Mx, the Y-axis drive motor My, and the Z-axis drive motor Mz at a certain time during operation. In this example, during a period in which the X-axis drive motor Mx is in a deceleration state (between time t2 and time t3), a period in which the Y-axis drive motor My is in an acceleration state in the power running state (between time t4 and time t5). ) Are overlapping. The period (time t4 to time t3) where both periods overlap is the polymerization period. During this period, the regenerative current generated by the X-axis drive motor Mx is used as a drive current (load current) for accelerating the Y-axis drive motor My. In addition, during the period in which the Y-axis driving motor My is in the decelerating state (between time t6 and time t7), the period in which the Z-axis driving motor Mz is in the acceleration state in the power running state (between time t8 and time t9) overlaps. ing. A period (time t8 to time t7) where both periods overlap is a polymerization period. In this period, the regenerative current generated by the Y-axis drive motor My is used as a drive current (load current) for accelerating the Z-axis drive motor Mz.

  In the present embodiment, power storage means 12 and charging circuit 13 that charges power storage means 12 using regenerative power are further provided. For this reason, the connection switching circuit 11 uses the regenerative power generated by one or more drive motors (Mx, My, or Mz) that are in a regenerative state outside the above-described polymerization period, and the charging circuit 13 charges the power storage unit 12. Thus, the connection relationship between the charging circuit 13, the X-axis motor control circuit 1, the Y-axis motor control circuit 2, and the Z-axis motor control circuit 3 is switched. In the example of FIG. 2, the regenerative current generated by the Z-axis drive motor Mz during the period during which the Z-axis drive motor Mz is decelerating (time t9 to time t10) is caused by the switching operation of the connection relationship switching circuit 11. Then, it is supplied to the power storage means 12 through the charging circuit 13, and the power storage means 12 is charged. The charging circuit 13 is connected to the power source 10 except during regeneration by the switching operation of the connection relationship switching circuit 11. Therefore, according to the present embodiment, regenerative power can be used effectively. In addition, it is arbitrary as what power supply the electrical storage means 12 is utilized, For example, it can be used as a power supply of the control part 4.

  In the above embodiment, the present invention is applied to a molded product take-out machine, but the present invention can naturally be applied to other multi-axis machine devices.

  The constituent requirements of various inventions disclosed in this specification and the drawings will be listed below.

(1) A plurality of drive motors that drive a plurality of shafts that operate when taking out a molded product, a plurality of motor control circuits that respectively control the plurality of drive motors based on operation timing, and the set An operation timing output unit that stores an operation timing in a storage unit and outputs the operation timing to the plurality of motor control circuits;
Provided between a power source and the plurality of motor control circuits, when at least one of the drive motors is in a regenerative state, regenerative power is used as drive power for the drive motor in at least one other power running state. A connection relationship switching circuit for switching a connection relationship between the plurality of motor control circuits and the power source so as to use electric power;
The operation timing is configured to include a polymerization period in which at least one other driving motor is in an acceleration state in a power running state when at least one of the driving motors is in a regenerative state,
The connection relationship switching circuit performs a switching operation so as to supply a regenerative current generated by the driving motor in the regenerative state as a load current to the driving motor in the power running state during the polymerization period. The featured product take-out machine.

  (2) The battery further includes a power storage unit and a charging circuit that charges the power storage unit using the regenerative power, and the connection relationship switching circuit includes one or more driving motors in a regenerative state other than the polymerization period. The regenerative power generated is used to switch the connection relationship between the charging circuit and the plurality of motor control circuits so that the charging circuit charges the power storage means (1). ) Molded product take-out machine as described in).

  (3) The molded article take-out machine according to (1), wherein the power storage means is charged using regenerative electric power generated by one or more of the driving motors in a regenerative state outside the polymerization period.

It is a figure which shows roughly the structure of the principal part of the operation control circuit of the molded article take-out machine as a specific example of the multi-axis machine apparatus of this invention which implements the method of invention. It is a figure which shows a part of operation timing. It is a perspective view when it sees from the molding machine injection nozzle side in the case of installing an example of a molded article extraction machine in an injection molding machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 X-axis motor control circuit 2 Y-axis motor control circuit 3 Z-axis motor control circuit 4 Control part 5 CPU
6 Operation Timing Output Unit 7 First Memory 8 Second Memory 9 Controller 10 Power Supply 11 Connection Relationship Switching Circuit 12 Power Storage Unit 13 Charging Circuit

Claims (2)

A control method for a multi-axis mechanical device for controlling a plurality of drive motors for driving a plurality of axes according to set operation timings,
The operation timing is configured to include a polymerization period in which at least one other driving motor is in an acceleration state in a power running state when at least one of the driving motors is in a regenerative state,
A control method for a multi-axis machine apparatus, wherein a regenerative current generated by the drive motor in the regenerative state is supplied as a load current to the drive motor in the power running state during the polymerization period. A plurality of drive motors for driving a plurality of shafts; a plurality of motor control circuits for controlling the plurality of drive motors based on operation timings; respectively, the set operation timings stored in a storage unit; A multi-axis mechanical device comprising an operation timing output unit for outputting the operation timing to the motor control circuit of
Provided between a power source and the plurality of motor control circuits, when at least one of the drive motors is in a regenerative state, regenerative power is used as drive power for the drive motor in at least one other power running state. A connection relationship switching circuit for switching a connection relationship between the plurality of motor control circuits and the power source so as to use electric power;
The operation timing is configured to include a polymerization period in which at least one other driving motor is in an acceleration state in a power running state when at least one of the driving motors is in a regenerative state,
The connection relation switching circuit performs a switching operation so as to supply a regenerative current generated by the driving motor in the regenerative state as a load current to the driving motor in the power running state during the polymerization period. Features multi-axis machinery.

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