JP2009285666A - Servo press arrangement and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for avoiding mechanical interference between servo press equipment and a carrying apparatus in the occurrence of power failure, in the servo press arrangement configured to synchronize the servo press equipment and the carrying apparatus with a maser signal. <P>SOLUTION: In the servo press arrangement 10 configured to synchronize the servo press equipment 100 and the carrying apparatuses 200, 300 with a maser signal 1, mutual supply of regeneration electric power is made possible in a main motor amplifier and a carrying apparatus motor amplifier. If power failure of the external power source 70 is detected by a power failure detector 3, the change rate of the maser signal 1 is lowered to zero. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a servo press facility including a servo press device and a transport device, and a control method thereof.

  A press machine is equipped with a crank mechanism, knuckle mechanism, link mechanism, etc. as a power conversion mechanism that drives a flywheel by a main motor and converts the flywheel drive force into a linear movement of the slide, and a clutch and brake device on the power transmission path Those equipped with are called mechanical presses. When such a mechanical press employs a kind of power conversion mechanism (for example, a crank mechanism), it cannot adopt the same slide motion as other types of power conversion mechanisms (for example, a knuckle mechanism or a link mechanism).

  On the other hand, in recent years, various servo press apparatuses having a configuration in which a drive shaft such as a crank shaft is rotationally driven by a servo motor to raise and lower a slide have been proposed. Since such a servo press can switch various slide motions by servo control, it can expand the adaptability to the press working mode and eliminate the flywheel, clutch & brake device as compared with the conventional mechanical press described above. There are advantages such as being able to.

  By the way, in a press facility, a transport device for carrying a workpiece in and out of the press device is attached to the press device. For this reason, it is necessary to control each operation | movement so that a press apparatus (specifically slide and metal mold | die) and a conveying apparatus do not mutually interfere mechanically.

In a servo press facility equipped with a servo press device and a transport device, as an example of such a control method for avoiding interference, the transport device can be operated in synchronization with the rotation of a crankshaft (main drive shaft) that drives a slide. Is disclosed in Patent Document 1 below.
However, the control method disclosed in Patent Document 1 has the following problems due to the method of operating the transport device in synchronization with the rotation of the main drive shaft (for example, the crankshaft).

(1) For example, the rotation of the main drive shaft fluctuates at the timing when the load changes suddenly, such as the moment when the die to be pressed contacts the workpiece or the moment when the workpiece is cut off by the cut-off processing. Since the fluctuation of the rotation of the main drive shaft affects the operation of the transfer device, the operation of the transfer device will not be smooth, the workpiece will be dropped, the motor torque of the transfer device will momentarily become excessive, and the protection device will be activated. There is a risk.
(2) When the main drive shaft is temporarily reversed in the middle of the process, the angle of the main drive shaft and the position of the transfer device do not correspond one-to-one, so that synchronization cannot be achieved.
(3) Since the motion of the transport device depends on the motion of the press machine, the motion of the press machine and the motion of the transport device cannot be changed independently, and it is difficult to optimize the motion curve.
(4) It is possible to adopt a configuration that does not have a main drive shaft in a servo press, such as a screw press, but in this case, since it does not have a main drive shaft, it is conveyed in synchronization with the rotation of the main drive shaft. The apparatus cannot be operated, or the operation of the press and the operation of the conveying apparatus can be performed only intermittently.

  In order to deal with the above problems, the present applicant has proposed a method of synchronizing the servo press device and the transport device with the master signal in Japanese Patent Application No. 2006-322836 (hereinafter referred to as the prior application) filed earlier. According to the method of this prior application, by synchronizing the servo press device and the transport device with the master signal, the servo press device and the transport device are synchronized indirectly via the master signal. Separated from device operation. As a result, even if the rotation of the main drive shaft of the servo press device fluctuates, the transport device operates smoothly based on the electronically generated master signal, so that problems such as dropping of the workpiece do not occur.

  However, when a power failure occurs, the motor that drives the servo press device and the transport device will not operate at the torque and speed according to the command from the controller, and the position of one or both of the servo press device and the transport device May deviate from the motion curve, and mechanical interference may occur between the servo press device and the transfer device.

The stopping method at the time of a power failure of the servo press apparatus is proposed in the following Patent Documents 2 and 3.
The method of Patent Document 2 uses a regenerative power generated at the time of rotation deceleration of a slide drive motor in a configuration in which the transport device is synchronized with slide movement, in particular, a crank angle. Secure.
In the method of Patent Document 3, electrical energy is stored in a capacitor during a press operation, and the motor is rotated and decelerated using the electrical energy stored in the capacitor during a power failure.

Japanese Patent No. 3340095 JP 2003-260530 A JP 2004-25287 A

However, in Patent Document 2, a power failure stop control method in a configuration in which the conveyance device is synchronized with the crank angle is described, but a power failure stop control method in a configuration in which the servo press device and the conveyance device are synchronized with a master signal. Is not described.
Moreover, in the said patent document 3, only the servo press apparatus is made into object, The stop method in the case of making a servo press apparatus and a conveyance apparatus interlock | cooperate is not described.

  In addition, the energy (that is, electric power) necessary for driving the motor of the servo press device changes every moment in one cycle of press working, and the most energy is required during the period in which the cushion device is pushed down. However, in Patent Documents 2 and 3 described above, no consideration is given, and there is a possibility that the equipment for power failure countermeasures will be enlarged.

  The present invention has been made in view of the above problems, and in a servo press facility configured to synchronize the servo press device and the transport device with the master signal, the power is generated between the servo press device and the transport device when a power failure occurs. It is an object of the present invention to provide means for avoiding mechanical interference.

  In order to solve the above-mentioned problems, the following technical means are employed in the servo press facility and the control method thereof according to the present invention.

(1) A servo press facility according to the present invention is a servo press device that receives power supply from an external power source and drives a slide by driving a slide by a main motor, wherein the main motor is a servo motor. A transfer device that carries in and / or unloads a workpiece from the servo press device in response to power supply from the external power source, a control device that controls the servo press device and the transfer device, and an external power source. A power supply circuit that supplies power to the servo press device and the transport device, the power supply circuit controlling the power supply to the main motor and regenerating power, and driving the transport device Controls the power supply to the transport device motor that is the source and detects the power failure of the external power source and the transport device motor amplifier that can regenerate power A power detector, and the main motor amplifier and the transport device motor amplifier are configured to allow regenerative power to be supplied to each other. The control device is configured to operate the servo press device and the transport device as desired. A master signal that changes with time according to the state is generated, and a command value for the slide position of the servo press device is uniquely output in synchronism with the change in the master signal value and the change in the master signal value. Synchronously output the command value of the operating position of the transfer device, and when a power failure of the external power source is detected by the power failure detector, the change rate of the master signal is reduced to zero. Features.

Here, the “conveying device” may mean either one of the carrying-in conveying device that loads the workpiece into the servo press device and the carrying-out conveying device that unloads the workpiece from the servo press device, or may mean both. .
The “transport device motor” refers to a drive source for causing the transport device to perform a transport operation. In the embodiment of the present invention, the “load-side transport device feed motor 202” and the “load-side transport device lift motor 204” are used. ”,“ Carry-out side conveyance device feed motor 302 ”, and“ carry-out side conveyance device lift motor 304 ”correspond to this.

  According to the configuration of the present invention described above, the servo press device and the transport device are configured to synchronize with the master signal, and regenerative power can be supplied mutually in the main motor amplifier and the motor amplifier for the transport device. When a power failure is detected by the power failure detector, the change rate of the master signal is reduced to zero. When the change rate of the master signal decreases during a power failure, the servo press device and the transport device decelerate and stop while maintaining the positional relationship defined by the motion curve. In addition, regenerative power is generated due to a decrease in the change rate of the master signal, and even during a power failure due to this regenerative power, the power necessary for motor control is ensured until the servo press device and the transport device are completely stopped. . Therefore, according to the present invention, it is possible to avoid mechanical interference between the servo press device and the transport device during a power failure.

(2) In the servo press facility of the above (1), the power supply circuit converts a converter for converting AC external power to DC, and the DC power converted by the converter to the main motor amplifier and the motor amplifier for the conveying device. The main motor amplifier and the transport device motor amplifier can mutually supply regenerative power via the DC bus.

  As in the above configuration, the DC bus may be a common power line in order to allow regenerative power to be mutually supplied in the main motor amplifier and the motor amplifier for the transport device.

(3) In the servo press facility according to (1), the power supply circuit includes a plurality of converters capable of converting AC external power supplied via an AC line into DC and regenerating power, and the plurality of converters. A plurality of DC buses for supplying the converted DC power to the main motor amplifier and the transport device motor amplifier, and the main motor amplifier and the transport device motor amplifier supply regenerative power via the AC line. Mutual supply is possible.

  As in the above configuration, in order to enable mutual supply of regenerative power in the main motor amplifier and the motor amplifier for conveyance device, a converter that can regenerate power is adopted and an AC line connected to an external power supply is shared. It is good also as an electric power line.

(4) In the servo press facility according to (1), the power supply circuit includes a plurality of converters capable of converting AC external power supplied via an AC line into DC and regenerating power, and the plurality of converters. A plurality of DC buses for supplying the converted DC power to the main motor amplifier and the transport device motor amplifier, wherein the main motor amplifier and the transport device motor amplifier are connected to the DC bus and / or the AC line; Mutual supply of regenerative power is possible via

  As in the above configuration, in order to enable mutual supply of regenerative power in the main motor amplifier and the motor amplifier for conveyance device, a converter that can regenerate power is adopted, and a DC bus is shared for some motors. For other motors, the AC line may be a common power line.

(5) In the servo press facility according to any one of (1) to (4), the servo press device includes a cushion device configured to hold a work peripheral portion between a blank holder and an upper mold, A cushion power source that is connected to the cushion device and generates a cushion pressure that is a holding force of the peripheral edge of the workpiece, and when the power failure of the external power source occurs, the cushion pressure is reduced or made zero.

  According to the above configuration, when a power failure occurs, the cushion pressure decreases or becomes zero, so that it is not necessary for the slide to press the cushion. As a result, the regenerative power is not consumed as the power for the slide to press the cushion, so that it is possible to reliably hold the power necessary for the motor control until the servo press device and the transport device are completely stopped. .

(6) In the servo press facility of the above (5), the cushion power source lowers or makes the cushion pressure zero based on a power failure detection signal from the power failure detector.
(7) In the servo press facility of the above (5), the cushion power source is actuated by a spring force or its own weight when a power failure occurs to reduce or reduce the cushion pressure.

  As described above, the means for lowering or reducing the cushion pressure in the cushion device may operate based on detection of a power failure, or may operate based on a spring force or its own weight when a power failure occurs. . According to the latter, it is possible to reduce the cushion pressure during a power failure without providing a path for transmitting a power failure detection signal to the cushion device.

(8) A method for controlling a servo press facility according to the present invention is a method in which a work is pressed by driving a slide by a main motor upon receiving power supply from an external power source, and the main motor is constituted by a servo motor. A servo press facility control method comprising: a press device; and a transport device that receives and supplies power from the external power source and carries workpieces into and / or out of the servo press device, the servo press device Has a main motor amplifier that controls power supply to the servo motor and can regenerate power, and the transport device controls power supply to the drive motor of the transport device and can regenerate power A power supply circuit that includes an amplifier and supplies power from the external power source to the servo press device and the transport device; and the main motor amplifier. The regenerative power can be mutually supplied in the motor amplifier for the transport device, and a master signal that changes over time is generated according to the desired operation state of the servo press device and the transport device, and the master signal Synchronously output the command value of the slide position of the servo press device in synchronization with the change of the value and output the command value of the operating position of the transport device in synchronization with the change of the master signal value, When a power failure of the external power supply is detected, the change rate of the master signal is reduced to zero.

  The control method of the present invention is an invention of a method corresponding to the servo press facility of (1) above. Therefore, according to the control method of the present invention, it is possible to avoid mechanical interference between the servo press device and the transport device during a power failure.

(9) In the method of controlling a servo press facility according to (8), the servo press device includes a cushion device configured to hold a work peripheral portion between a blank holder and an upper die, and an external power source When the power failure occurs, in the cushion device, the cushion pressure, which is the holding force of the work peripheral portion, is reduced or made zero.

  According to the above method, since the regenerative power is not consumed as the power for the slide to press the cushion, the power necessary for the motor control is surely maintained until the servo press device and the transport device are completely stopped. can do.

  According to the present invention, in the servo press equipment configured to synchronize the servo press device and the transport device with the master signal, mechanical interference between the servo press device and the transport device can be avoided at the time of power failure.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the common part in each figure, and the overlapping description is abbreviate | omitted.

  FIG. 1 is an overall configuration diagram of a servo press facility 10 according to an embodiment of the present invention. The servo press facility 10 includes a servo press device 100 that presses a workpiece (not shown), a loading-side transfer device 200 that loads a workpiece before pressing into the servo press device 100, and a servo press device that transfers the workpiece after pressing. 100, a carry-out side conveyance device 300 that is carried out from 100, and a servo press device 100, a carry-in side conveyance device 200, and a control device 40 that controls the carry-out side conveyance device 300.

First, the configuration of the servo press apparatus 100 will be described.
In the servo press apparatus 100, the main motor 101 is constituted by a servo motor. The rotation of the servo-controlled main motor 101 is converted into the vertical movement of the slide 103 by the slide drive mechanism 102. An upper mold 104 is attached to the slide 103 and moves up and down together with the slide 103. Opposed to the upper mold 104, a lower mold 106 and a blank holder 105 for holding a wrinkle are provided.

  The lower mold 106 is installed on the bolster 107. The blank holder 105 moves up and down together with a cushion device 108 configured to hold the work peripheral edge between the blank holder 105 and the upper mold 104. A cushion power source 109 for generating a wrinkle pressing force (cushion pressure) is connected to the cushion device 108.

  When a work (not shown) is inserted between the upper mold 104 and the lower mold 106 and the main motor 101 is rotated, the slide 103 is lowered to press-mold the work between the upper mold 104 and the lower mold 106. Is done. At this time, the peripheral edge portion of the work is sandwiched between the blank holder 105 that moves up and down together with the upper mold 104 and the cushion device 108, and wrinkle pressing is performed. The force generated during press molding is supported by the frame 110.

Next, the configuration of the carry-in side conveyance device 200 and the carry-out side conveyance device 300 will be described.
The carry-in side conveyance device 200 includes a carry-in side conveyance device work gripping tool 201 that grips a workpiece by sucking or pinching the workpiece in a vacuum. The carry-in side conveyance device work gripping tool 201 is moved in the feed direction (left and right direction in the figure) by the carry-in side conveyance device feed mechanism 203 that converts the rotation of the carry-in side conveyance device feed motor 202 into a linear motion. The loading-side transfer device work gripping tool 201 is moved in the lift direction (vertical direction in the figure) by a loading-side transfer device lift mechanism 205 that converts the rotation of the motor 204 into linear motion.

The carry-out side conveyance device 300 has the same configuration as the carry-in side conveyance device 200, and the carry-out side conveyance device feed mechanism 303 that converts the rotation of the carry-out side conveyance device feed motor 302 into a linear motion grips the carry-out side conveyance device work. When the tool 301 is moved in the feed direction (left-right direction in the figure), the unloading-side transfer device work gripping tool 301 is lifted by the unloading-side transfer device lift mechanism 305 that converts the rotation of the unloading-side transfer device lift motor 304 into linear motion. It is moved in the vertical direction in the figure.
In the following description, one or both of the carry-in side conveyance device 200 and the carry-out side conveyance device 300 may be simply referred to as a “conveyance device”.

  The motor (main motor 101, transport device feed motors 202 and 302, transport device lift motors 204 and 304) can be of any method as long as the torque and rotation speed are variable in combination with an inverter and power regeneration is possible. A motor can be used. For example, a three-phase induction motor, a three-phase synchronous motor, a permanent magnet synchronous motor, a direct current motor, or the like can be used.

  Examples of the slide drive mechanism 102 include an eccentric system, a link system, a crankless system, a toggle system, and a ball screw system. There is also a method in which a linear motor is used as the motor and the slide drive mechanism 102 is omitted.

  Examples of the cushion device 108 include a pneumatic method in which air is enclosed in a cylinder and the piston is moved up and down with air pressure, a hydraulic method in which oil is flowed into and out of the cylinder and the piston is moved up and down with hydraulic pressure, and an electric motor is rotated. There is an electric system that converts the movement into a vertical movement by a mechanism such as a ball screw or a rack and pinion.

  The cushion power source 109 differs depending on the method of the cushion device 108, for example, as follows. When the cushion device 108 is a pneumatic system, the cushion power source 109 is an air tank, an air pipe, an air valve, or the like. When the cushion device 108 is a hydraulic system, the cushion power source 109 is a hydraulic pump, a hydraulic pipe, a hydraulic valve, or the like. When the cushion device 108 is an electric system, the cushion power source 109 is a motor / inverter or the like.

  As the transfer devices 200 and 300, any mechanism can be used as long as it is driven by a motor and can load and unload a workpiece. In addition to the mechanism based on the combination of linear motions as illustrated in FIG. 1, a link mechanism such as a Doppin feeder may be used. An industrial robot may be used. Examples of the feed mechanism / lift mechanism include a ball screw system, a rack and pinion system, and a pantograph system. The mechanism may be different between the carry-in side and the carry-out side. Those having a degree of freedom of movement other than feed and lift, for example, those capable of moving in the front-depth direction (perpendicular to the paper surface) in FIG.

Next, the configuration of the control device 40 will be described.
The control device 40 includes a master signal generator 42, a press controller 44, a conveyance controller 46, and a cushion pressure controller 72. The control device 40 may be a single control device (for example, an NC control device) or a composite control device including one upper control device and a plurality of lower control devices.

The master signal generator 42 generates a master signal 1 having a value M that changes in time between values A and B in accordance with the desired operation state of the servo press device 100 and the conveying devices 200 and 300 (FIG. 2 ( See A)).
Here, the meaning of “according to the desired driving state” means “according to the intention of wanting to drive in this way (want to rotate forward / reverse / want to move fast / move slowly)”.

The time pattern of the master signal is changed according to the desired operation state, and the motion curve does not depend on the desired operation state.
That is, in the present invention, the synchronization relationship between the master signal and the servo press or between the master signal and the transport device is defined by the motion curve, and the time change pattern of the master signal is switched according to a state called “desired operation state”. .

  The press controller 44 stores a motion curve (FIG. 2B) that gives a slide position corresponding to the master signal value M, and the slide position of the servo press device 100 is synchronized with the change of the master signal value M. The command value is uniquely output, and the slide 103 is controlled to move to the position command value corresponding to the change of the master signal value M in synchronization with the change of the master signal value M.

  In this example, the conveyance controller 46 is composed of a carry-in conveyance controller 46A and a carry-out conveyance controller 46B, and each provides a motion curve that gives the operation positions of the conveyance devices 200 and 300 corresponding to the master signal value M (FIG. 2C ) To (F)) are stored, and the command value of the operating position of the transport device 200, 300 is uniquely output in synchronization with the change in the master signal value M, and in synchronization with the change in the master signal value M. Control is performed to move the transport device to the corresponding operating position.

  The motion curve of the transport controller 46 (46A, 46B) includes a feed motion curve that gives the feed position of the transport devices 200 and 300 and a lift motion curve that gives the lift position of the transport device, and changes in the master signal value M, respectively. The command value of the operation position corresponding to it is uniquely output in synchronization with

FIG. 2 is a diagram illustrating a relationship for one cycle when the servo press device 100 and the conveying devices 200 and 300 are operated in a normal direction with a cycle (cycle time) T in synchronization.
FIG. 2A shows the relationship between the elapsed time t within the period T and the master signal. In this example, the master signal generated by the master signal generator 42 is changed from an initial value A (in this example, 0) to a final value B (B is 1 for example) at a certain period T for simplification of explanation. To increase linearly. That is, the value M of the master signal 1 at the elapsed time t within the period T can be given by M = (B−A) × t / T + A. The master signal 1 is reset every period T and is continuously repeated.

  FIG. 2B shows a motion curve of the slide 103. The motion curve of the slide 103 defines the position of the slide 103 corresponding to the value M of the master signal value 1. That is, the position of the slide 103 is not directly determined for a certain time t for each period T, and the position of the slide 103 is determined corresponding to the value M of the master signal value 1 with respect to the time t. The slide 103 is controlled to move to a position command value corresponding to the position command value in synchronization with the control. Therefore, if the relationship between the elapsed time t in the period T and the master signal 1 is changed (for example, change from a straight line to an arbitrary curve), the value M of the master signal value 1 for the same time t changes. Correspondingly, the position of the slide 103 also changes.

  FIG. 2C shows a motion curve of the feed position of the carry-in side conveyance device 200. FIG. 2D shows a motion curve of the lift position of the carry-in side conveyance device 200. In the motion curves of FIGS. 2C and 2D, control is performed so that the conveying device is moved to the corresponding operation position in synchronization with the change of the master signal value M.

  FIG. 2E shows a motion curve of the feed position of the carry-out side conveyance device 300. FIG. 2F shows a motion curve of the lift position of the carry-out side conveyance device 300. In the motion curves of FIGS. 2E and 2F, control is performed so that the conveying device is moved to the corresponding operation position in synchronization with the change of the master signal value M.

  The transport devices 200 and 300 also change the value M of the master signal value 1 for the same time t if the relationship between the elapsed time t in the period T and the master signal 1 is changed (for example, change from a straight line to a curve). Therefore, the operating position changes correspondingly.

  As a method of holding a motion curve, there are a method of storing values sampled at appropriate intervals in a table and interpolating between them with a polynomial or a spline, a method of expressing the whole curve or a function for each appropriately divided section, etc. is there.

  The motion curve is determined so that the press machine and the transport apparatus do not mechanically interfere within the range of the performance of the press machine and the transport apparatus. The method of determining the motion curve can be determined offline using a 3D CAD with interference check function, or the motion curve can be determined online by actually operating the press machine and transport device by changing the motion curve. There are ways to do it.

  As shown in this example, when the master signal 1 is reset every cycle T and is continuously repeated, the movement of the slide 103 and the conveying devices 200 and 300 with respect to time for two cycles of the master signal is shown in FIG. It looks like the curve on the right side of 3. The curve on the left side of FIG. 3 is the same motion curve as FIG.

  FIG. 4 is a diagram illustrating an example of a master signal pattern corresponding to a desired operation state. When it is desired to change the desired operation state of the servo press device 100 and the transfer devices 200 and 300, it can be realized by changing the master signal with respect to time as shown in FIG.

  For example, as shown in (A) and (B), the cycle time can be changed for each cycle by changing the time of one cycle of the master signal for each cycle (T1, T2, T3...). In (A), the change rate of the master signal with respect to time is constant, but as shown in (B), the change rate of the master signal with respect to time may be continuously changed.

When it is desired to stop at an arbitrary place, as shown in (C), a period in which the value of the master signal is constant (change rate is zero) in one cycle may be provided.
When the servo press device 100 and the conveying device are once stopped from normal rotation and further reverse rotation is desired, the change rate of the master signal with respect to time may be reversed as shown in (D).

  According to the servo press facility 10 configured as described above, the servo press apparatus 100 and the transport apparatuses 200 and 300 are indirectly connected via the master signal by synchronizing the servo press apparatus 100 and the transport apparatus with the master signal. Since the synchronization is performed, the operations of the conveying devices 200 and 300 are separated from the operations of the servo press device 100. As a result, even if the rotation of the main drive shaft of the servo press device 100 fluctuates, the conveying devices 200 and 300 operate smoothly based on the electronically generated master signal, so that problems such as dropping of the workpiece occur. Absent.

  When changing the motions of the transport devices 200 and 300, the motion curve for associating the operation positions of the transport devices may be changed, and the motion curve of the servo press device 100 is not affected thereby. Further, in the servo press device 100 and the conveying devices 200 and 300, the operations can be adjusted and optimized independently. It is also possible to set a motion curve that includes reverse rotation.

  The motion curve can be changed according to conditions such as the shape of the upper mold 104 and the lower mold 106, the workpiece shape, the workpiece material, and the slide 103 motion suitable for workpiece molding. For example, in the case of a press machine that molds various workpieces by exchanging dies, the optimal motion curve is obtained in advance for each die and workpiece, and the motion curve is changed simultaneously when changing the die and workpiece. It is also possible to configure.

  Even in the case of a servo press that does not have a main drive shaft, such as a screw press, the operation of the press and the operation of the conveying device can be interlocked from moment to moment.

  As shown in FIG. 1, the power failure detector 3 is configured to send a power failure detection signal 71 to the master signal generator 42 and the cushion pressure controller 72 when a power failure is detected. This power failure detector 3 is provided in a power supply circuit 80 described later. The cushion pressure controller 72 is configured to send a cushion pressure reduction command 73 to the cushion power source 109 when receiving the power failure detection signal 71. When the cushion power source 109 receives the cushion pressure reduction command 73, the cushion power source 109 is configured to reduce or zero the cushion pressure (wrinkle pressing force).

  For example, when the cushion device 108 is a pneumatic system, a valve that opens the air pressure to atmospheric pressure is opened. When the cushion device 108 is a hydraulic system, a valve that opens the hydraulic pressure is opened. When the cushion device 108 is an electric system, Is configured to open the contactor that cuts off power to the motor, servo-off the inverter, and provide a mechanical clutch on the motor shaft to release the clutch.

  As a means for lowering or reducing the cushion pressure during a power failure, what has been described above has been described based on the detection of a power failure, but instead of such a configuration, it operates by spring force or its own weight when a power failure occurs. You may adopt what to do. For example, if the cushion power source 109 is a pneumatic system, a valve that operates and exhausts by a spring or natural drop when a power failure occurs, a spring or a relief valve that relieves due to a natural fall if a power failure occurs, or a spring or A contactor that is turned off by natural fall can be used. According to such a configuration, the cushion pressure can be reduced during a power failure without providing a path for transmitting the power failure detection signal 71 to the cushion pressure controller 72.

  Here, the following modifications may be added to the servo press facility 10 described above.

  In FIG. 1, the case where there is a conveyance device before and after one servo press device is shown, but when a production line is constituted by a plurality of servo press devices and a plurality of conveyance devices, a master signal is sent to a plurality of servo press devices, This method can be applied to the entire line by inputting to the transfer device. By providing an independent press controller and transport controller for each servo press device and transport device, each servo press device and transport device is suitable for workpiece processing characteristics, work transport distance and avoidance of interference. Therefore, it is possible to set a motion curve so as to reduce the dead time for transferring the workpiece between the adjacent press machine and the conveying device.

  In the above description, the example in which the press machine and the transport device operate in synchronization with the master signal throughout the entire cycle of the operation of the press machine and the transport device has been described. However, the interference conditions between the press machine and the transport device are severe. In other words, the transport device is placing the work inside the press machine. The press machine and the transport device operate in synchronization with the master signal only during the period of taking out the work, and the other time period, that is, the press machine and the transport device. It is also possible to adopt a configuration in which the press machine and the conveying device operate independently during a period in which the interference condition is loose.

In FIG. 1, the servo press device 100 that mechanically converts the rotation of the main motor 101 into the linear motion of the slide 103 is shown, but the present invention can also be applied to a servo press device configured to drive the slide 103 using a linear motor. It is.
The cushion device 108 may be configured to synchronize the movement of the cushion with the master signal.

  As shown in FIG. 1, the servo press facility 10 according to the present invention further includes a power supply circuit 80 that supplies power from an external power source 70 to the servo press apparatus 100 and the transport apparatuses 200 and 300. FIG. 5 is a diagram illustrating a power supply circuit 80A of the first configuration example.

  As shown in FIG. 5, the power supply circuit 80 </ b> A of the first configuration example includes a main motor amplifier 11 </ b> A that is an inverter that controls power supply to the main motor 101 and can regenerate power, and a drive source for the transport apparatuses 200 and 300. The transport device motor amplifiers 11B, 11C, 11D, and 11E are inverters that control power supply to the transport device motors (the transport device feed motors 202 and 302 and the transport device lift motors 204 and 304) and can regenerate power. And the power failure detector 3 for detecting a power failure of the external power source 70, and the main motor amplifier 11A and the motor amplifiers 11B, 11C, 11D, and 11E for the transport device can be configured to mutually supply regenerative power. Yes.

  In the power supply circuit 80 </ b> A, AC power is received from the external power supply 70 via the AC line 2. The external power source 70 is usually a power company or a private power generation facility. As the AC line 2, a three-phase AC is often used as shown in FIG. The AC line 2 is provided with a power failure detector 3 and detects a power failure of the external power source 70. The alternating current of the alternating current line 2 is converted into direct current by the converter 4 and electric power is supplied to the direct current bus 5. The converter 4 may be either regenerative or non-regenerative, and FIG. 5 shows a non-regenerative diode converter 4 as an example.

  The DC bus 5 is provided with a storage element 6 for charging and discharging for smoothing. The power storage element 6 may not be provided independently, but may be built in the converter 4 or the inverter. The motor amplifier 11A controls the current / voltage to the main motor 101 so that the main motor rotates at a desired torque / rotation speed. Here, if the main motor 101 is powered, power is supplied from the DC bus 5 to the main motor 101 via the motor amplifier 11A. If the main motor 101 is regenerating, the motor amplifier 11A is transferred from the main motor 101. Electric power is supplied to the DC bus 5 via the relay. The same applies to the other motors 202, 204, 302, 304 and motor amplifiers 11B to 11E.

  As an inverter system that can be regenerated, for example, when the motor is an AC motor such as an induction motor or a synchronous motor, a system that performs pulse width modulation (PWM modulation) on a power control element such as an IGBT, a power transistor, or a power MOSFET, or a motor In the case of a DC motor, there is a method for controlling the ignition timing of the thyristor. The systems of the plurality of motors / inverters (5 sets in the example of FIG. 5) may be different. In order to prevent the voltage of the DC bus 5 from becoming excessive, a discharge resistor (not shown) for discharging the DC bus 5 may be provided.

  As the power failure detector 3, for example, one or both of the phase voltage and the phase voltage of the AC line 2 are constantly measured, and the voltage is maintained for a certain period of time (usually a time corresponding to one or several cycles of AC). There is a method of judging a power outage if it is smaller than the specified value. For power failure detection, the voltage change of the DC bus 5 for one turn of the master signal under the same operating conditions and load conditions is recorded as a reference value, and it is determined that a power failure occurs when the DC bus 5 voltage drops below that value. There is also a method.

As the converter 4, in addition to the diode converter, a thyristor converter, a converter that can be regenerated using a power control element such as an IGBT, or the like can be used. A multiple rectification method may be used to improve the waveform.
The storage element 6 may be of any type as long as it can charge and discharge electricity, but an electrolytic capacitor, an electric double layer capacitor, various storage batteries, and the like can be used.

  Next, operations of the control device 40, the servo press device 100, and the transfer devices 200 and 300 when a power failure occurs will be described. When the power failure detector 3 detects a power failure and the power failure detection signal 71 is sent to the master signal generator 42 and the cushion pressure controller 72, the master signal generator 42 operates as follows.

  The master signal generator 42 decelerates the change rate of the master signal to zero, that is, prevents the master signal from changing with time. FIG. 6A shows an example of the master signal when the master signal is rotating forward when the power failure detection signal 71 is received, and FIG. 6B shows an example when the master signal is rotating reversely. While the master signal is decelerated and stopped, as described above, the servo press device 100 (slide 103), the carry-in side transfer device 200, and the carry-out side transfer device 300 follow the target position determined by the master signal and the motion curve. Control is continued to do.

  The movement of the slide 103 will be described as an example. When the master signal changes at a constant rate as shown in FIG. 7A, the motor (main motor 101) that drives the slide 103 follows the motion curve. Assume that the motor operates at the rotation speed shown in FIG. The torque of the motor is as shown in FIG. 7C, and the power supplied from the DC bus 5 to the motor via the inverter is as shown in FIG. 7D. Here, among the torque shown in FIG. 7C, the torque required for pushing the cushion is from 1.6 seconds to 2.2 seconds, and the other torque is torque for acceleration / deceleration.

  As for the electric power shown in FIG. 7D, a positive value is power running (electric power is supplied from the DC bus 5 to the motor via the inverter), and a negative value is regenerated (electric power is DC from the motor via the inverter). To be supplied to the bus 5). Here, if a power failure is detected at time 1 second, the master signal decelerates at 0.4 seconds, and stops at time 1.4 seconds, the master signal waveform is as shown in FIG. Although the motion curves are the same, the master signal changes from the waveform shown in FIG. 7 (a) to the waveform shown in FIG. 7 (e), so that the motor rotation speed, torque, and power are as shown in FIG. As shown in (g) and (h).

  Here, paying attention to the power between 1 second and 1.4 seconds, when the master signal changes at a constant rate, no regeneration occurs as shown in FIG. Is decelerated (the change rate of the master signal decreases), the motor following the motion curve also decelerates, and regeneration occurs as shown in FIG. 7 (h) (the power value becomes negative). I understand). That is, it can be seen that power regeneration can be performed only by decelerating the master signal without changing the normal control method of synchronizing the operations of the servo press device 100 (slide 103) and the conveying device with the master signal. Even in the motors of the transport apparatus other than the slide 103, regeneration is performed based on the same principle by decelerating the master signal.

  In the circuit shown in FIG. 5, since the electric power regenerated from any motor is supplied to the DC bus 5, the external power supply 70 is out of power and no power is supplied from the external power supply 70 via the converter 4. Nevertheless, the voltage of the DC bus 5 is maintained. For example, depending on the setting of the motion curve, such as when the motor is set to stop when a power failure is detected, some of the motors will regenerate even if the master signal is decelerated. Although not performed, since all the motors are connected to the DC bus 5 via inverters, the voltage of the DC bus 5 is maintained if power regeneration is performed by one motor. That is, the control of the motor by the inverter can be continued until the master signal is stopped and the motor is stopped.

  Note that the control device 40 itself operates by receiving power from the external power supply 70 in normal times, but at the time of a power failure, the power supply for operating the control device 40 is secured by switching to the backup power supply 81 as shown in FIG. Is done. Or it is good also as a structure which ensures the electric power required for the control apparatus 40 by converting a part of regenerative electric power from the servo press apparatus 100 mentioned above and the motor of a conveying apparatus into the voltage suitable for the control apparatus 40, and supplying it. . As the backup power source 81, a power generation device independent of the external power source 70, or when the power from the external power source 70 is stored in a storage battery, an electric double layer capacitor, or a flywheel in a normal state, There is a method of supplying power from a capacitor or a flywheel.

When the power failure detector 3 detects a power failure and the power failure detection signal 71 is sent to the master signal generator 42 and the cushion pressure controller 72, the cushion pressure controller 72 operates as follows.
The cushion pressure controller 72 sends a cushion pressure reduction command 73 to the cushion power source 109 to reduce the cushion pressure (wrinkle pressing force). Hereinafter, an example in which the cushion pressure is reduced to zero will be described with reference to FIG.

  Assume that a power failure occurs during the time when the slide 103 is pressing the cushion, while operating with the same motion curve as in the case shown in FIG. For example, a power failure occurs at time 1.7 seconds, the master signal is decelerated over 0.4 seconds, and the master signal stops at time 2.1 seconds. If the cushion pressure is not reduced at the time of power failure detection, the master signal, the motor rotation speed, and the motor power change as shown in FIGS. 8A, 8B, and 8C, respectively. Between time 1.7 seconds and 2.1 seconds, the power regenerated by decelerating the master signal exceeds the power required to push the cushion, so the motor as shown in FIG. The power is a positive value, that is, power flows from the DC bus 5 to the motor via the inverter.

  On the other hand, if the cushion pressure is set to zero when a power failure is detected, the slide 103 does not need to press the cushion, so that the motor torque changes as shown in FIG. 8 (e), and the motor power is shown in FIG. 8 (f). To change. After power failure detection (after time 1.7 seconds), the motor power is negative, that is, power is regenerated from the motor to the DC bus 5 via the inverter. Even when the cushion pressure is set to zero when a power failure is detected, changes in the master signal and the motor rotation speed are the same as those in FIGS. 8A and 8B.

The actions and effects of the above-described embodiment of the present invention are summarized as follows.
The servo press device 100 and the transport devices 200 and 300 are configured to synchronize with the master signal, and the main motor amplifier 11A and the transport device motor amplifiers 11B to 11E can mutually supply regenerative power, resulting in a power failure. When the power failure of the external power source 70 is detected by the detector 3, the change rate of the master signal is reduced to zero.

  When the change rate of the master signal is reduced during a power failure, the servo press device 100 and the transport devices 200 and 300 are decelerated and stopped while maintaining the positional relationship defined by the motion curves. In addition, regenerative power is generated due to a decrease in the change rate of the master signal, and even during a power failure due to this regenerative power, power necessary for motor control is ensured until the servo press device 100 and the transport device are completely stopped. The Therefore, it is possible to avoid mechanical interference between the servo press device 100 and the transport device during a power failure.

  In addition, when a power failure occurs, the cushion pressure decreases or becomes zero, so that it is not necessary for the slide 103 to press the cushion. Thereby, since the regenerative power is not consumed as the power for the slide 103 to press the cushion, the power necessary for the motor control until the servo press device 100 and the transport device are completely stopped is surely held. Can do.

  FIG. 9 shows a power supply circuit 80B of the second configuration example. The power supply circuit 80B converts the AC external power supplied via the AC line 2 into DC and converts the DC power converted by the plurality of converters 4A to 4E and the converters 4A to 4E into main power. A motor amplifier 11A and a plurality of DC buses 5A to 5E supplied to the motor amplifiers 11B to 11E for the conveying device are provided. The main motor amplifier 11A and the motor amplifiers 11B to 11E for the conveying device are regenerated via the AC line 2. Mutual supply is possible.

  In the power supply circuit 80A of the first configuration example, all the motors regenerate power to the DC bus 5, but in the second configuration example, the regenerative converters 4A to 4E are used, and all the motors are connected to the AC line 2. By regenerating the power, the operation can be continued by maintaining the voltage of the AC line 2 in the event of a power failure. Since the voltage of the AC line 2 is maintained by the power regeneration, the power failure detector 3 holds that the power failure has been detected when the power failure is detected even for a moment, that is, when the external power source 70 detects a power failure.

  FIG. 10 shows a power supply circuit 80C of the third configuration example. This power supply circuit 80C converts a plurality of converters 4A and 4B capable of converting AC external power supplied via the AC line 2 into DC and regenerating power, and DC power converted by the plurality of converters as a main motor amplifier 11A. And a plurality of DC buses 5A and 5B supplied to the transport apparatus motor amplifiers 11B to 11E. The main motor amplifier 11A and the transport apparatus motor amplifiers 11B to 11E are connected via the DC bus 5 and / or the AC line 2. This enables mutual supply of regenerative power.

  That is, the third configuration example is a combination of the first configuration example and the second configuration example, and in order to enable mutual supply of regenerative power in the main motor amplifier 11A and the motor amplifiers 11B to 11E for the conveyance device, Converters 4A and 4B employ those that can regenerate power. For some motors, the DC bus 5 is a common power line, and for other motors, the AC line 2 is a common power line.

  In the embodiment, the case where there are five motors / inverters is shown, but the present invention can be applied regardless of the number of motors / inverters.

  When a production line is composed of a plurality of servo press devices and a plurality of transport devices, a power supply circuit as shown in FIG. 5 (or FIG. 9 or FIG. 10) is provided for each servo press device and the transport devices before and after the servo press device. It may be provided, or a power supply circuit as shown in FIG. 5 (or FIG. 9 or FIG. 10) may be provided across a plurality of servo press devices / conveyance devices.

  If there is a time delay in detecting a power failure by the power failure detector 3, the capacity of the storage element provided in the DC bus is selected appropriately, and the power necessary to power the motor during the time delay until the power failure is detected. You may supply from an electrical storage element.

  Although the embodiments of the present invention have been described above, the embodiments of the present invention disclosed above are merely examples, and the scope of the present invention is not limited to these embodiments. . The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

1 is an overall configuration diagram of a servo press facility according to an embodiment of the present invention. It is a figure which shows the relationship for one period in the case of making a servo press apparatus and a conveying apparatus synchronize and drive | work normally by the period (cycle time) T. FIG. It is a figure which shows the motion of the slide and conveyance apparatus with respect to time about 2 periods of a master signal. It is a figure which shows the example of the pattern of the master signal corresponding to a desired driving | running state. It is a figure which shows the power supply circuit of a 1st structural example. It is a figure which shows the example of a master signal when decelerating the change rate of a master signal, and making it zero. It is a figure which shows the mode of the motor rotation speed of the main motor with respect to the change of a master signal, a motor torque, and the change of electric power. It is another figure which shows the mode of the change of the motor rotation speed of the main motor, the motor torque, and electric power with respect to the change of a master signal. It is a figure which shows the electric power supply circuit of the 2nd structural example. It is a figure which shows the electric power supply circuit of the 3rd structural example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Master signal 3 Power failure detector 11A-11E Motor amplifier 40 Control apparatus 42 Master signal generator 44 Press controller 46A Carry-in side conveyance controller 46B Carry-out side conveyance controller 70 External power supply 71 Power failure detection signal 72 Cushion pressure controller 73 Cushion Pressure drop commands 80, 80A, 80B, 80C Power supply circuit 100 Servo press device 101 Main motor 108 Cushion device 109 Cushion power source 200 Carry-in side transport device 202 Carry-in side transport device feed motor 204 Carry-in side transport device lift motor 300 Carry-out side transport Device 302 Unloading-side transfer device feed motor 304 Unloading-side transfer device lift motor

Claims (9)

A servo press device that receives power supply from an external power source and drives a slide by driving a slide with a main motor, and the main motor is a servo motor;
A transport device that carries in and / or unloads a workpiece with respect to the servo press device in response to power supply from the external power source;
A control device for controlling the servo press device and the transport device;
A power supply circuit for supplying power from the external power source to the servo press device and the conveying device,
The power supply circuit controls the power supply to the main motor and can regenerate power, and the power supply circuit to control the power supply to the transport device motor that is a drive source of the transport device and can perform power regeneration It has a motor amplifier for the device and a power failure detector for detecting a power failure of the external power supply, and is configured so that regenerative power can be mutually supplied in the main motor amplifier and the motor amplifier for the transport device,
The control device generates a master signal that changes over time according to a desired operation state of the servo press device and the transport device, and commands the slide position of the servo press device in synchronization with the change of the master signal value. A value is uniquely output and a command value of the operation position of the transfer device is uniquely output in synchronization with a change in the master signal value, and when a power failure of the external power source is detected by the power failure detector, Servo press equipment characterized by reducing the change rate of the master signal to zero. The power supply circuit includes a converter that converts AC external power to DC, and a DC bus that supplies the DC power converted by the converter to the main motor amplifier and the motor amplifier for the conveyance device,
The servo press facility according to claim 1, wherein the main motor amplifier and the conveying apparatus motor amplifier are capable of mutually supplying regenerative power via the DC bus. The power supply circuit includes a plurality of converters capable of converting AC external power supplied via an AC line into direct current and regenerating power, the DC power converted by the plurality of converters, the main motor amplifier, and the transport device. A plurality of DC buses to be supplied to the motor amplifier
The servo press facility according to claim 1, wherein the main motor amplifier and the transport device motor amplifier are capable of mutually supplying regenerative power via the AC line. The power supply circuit includes a plurality of converters capable of converting AC external power supplied via an AC line into direct current and regenerating power, the DC power converted by the plurality of converters, the main motor amplifier, and the transport device. A plurality of DC buses to be supplied to the motor amplifier
The servo press facility according to claim 1, wherein the main motor amplifier and the motor amplifier for the conveying device can mutually supply regenerative power via the DC bus and / or the AC line.   The servo press device generates a cushion pressure that is connected to the cushion device and is a holding force of the workpiece peripheral portion, and is configured to hold the workpiece peripheral portion between the blank holder and the upper mold. The servo press facility according to claim 1, further comprising a cushion power source, wherein the cushion pressure is reduced or zeroed when a power failure occurs in an external power source.   The servo press facility according to claim 5, wherein the cushion power source lowers or makes the cushion pressure zero based on a power failure detection signal from the power failure detector.   The servo press facility according to claim 5, wherein the cushion power source is operated by a spring force or its own weight to reduce or reduce the cushion pressure when a power failure occurs. It receives power supply from an external power source and drives the slide by driving a slide with a main motor. The main motor receives a power supply from the external power source and a servo press device in which the main motor is composed of a servo motor. A control method of a servo press facility comprising a conveying device for carrying in and / or carrying out a workpiece with respect to the servo press device,
The servo press device has a main motor amplifier that controls power supply to the servo motor and can regenerate power,
The transport device has a motor amplifier for a transport device that controls power supply to a drive motor of the transport device and can regenerate power,
A power supply circuit that supplies power from the external power source to the servo press device and the transport device is configured so that regenerative power can be mutually supplied in the main motor amplifier and the transport device motor amplifier,
A master signal that changes with time is generated according to a desired operation state of the servo press device and the transport device, and a command value for the slide position of the servo press device is uniquely defined in synchronization with the change of the master signal value. In addition, the command value of the operating position of the transfer device is uniquely output in synchronization with the change of the master signal value, and when the power failure of the external power supply is detected, the change rate of the master signal is reduced. A method of controlling a servo press facility, characterized in that it is zero. The servo press device includes a cushion device configured to hold a work peripheral portion between a blank holder and an upper die,
The method of controlling a servo press facility according to claim 8, wherein, when a power failure of an external power source occurs, the cushion pressure, which is a holding force of a work peripheral portion, is reduced or zeroed in the cushion device.

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