JP2008260034A - Pressing machine, and method for controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressing machine using servo control where, during the stop of a slide, power consumption can be reduced, and deterioration in a power transferring mechanism caused by repeated tooth surface bearing between gears can be prevented by the fine normal/reverse rotation driving of a servo motor. <P>SOLUTION: The pressing machine comprises: a switching mechanism 13 provided at a power transferring path from a servo motor 7 to a slide 5, and capable of switching a power transferring state of transferring power from the servo motor 7 to the slide 5 and a power non-transferring state not transferring the power from the servo motor 7 to the slide 5; and a slide holding mechanism 15 capable of moving between a non-interfering position not interfering with the movement of the slide 5 and a slide holding position holding the slide 5 to a fixed position. A controller 11 stops the slide 5 by the rotation angle control of the servo motor 7, thereafter allows the slide holding mechanism 15 to operate to the slide holding position, and then switches the switching mechanism 13 to a power non-transferring state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a press machine, and more particularly, to a press machine that performs press by moving a slide up and down and stopping by servo control.

  The press machine includes an upper mold and a lower mold for pressing the workpiece in the vertical direction, a slide on which the upper mold is fixed to the lower surface and moved up and down, a drive motor for moving up and down the slide, And a conversion mechanism that converts the rotational motion of the drive motor into a lifting motion and transmits it to the slide.

  In the operation of the press machine, the press-formed workpiece (panel, etc.) is unloaded from between the upper mold and the lower mold, and the panel before press processing is placed between the upper mold and the lower mold. Carry in. Therefore, every time one panel is formed, the slide is raised and stopped, and when the panel is loaded, the operation of lowering the slide again is repeated. Since such slide lowering / raising / stopping is performed every cycle, it is desirable to be able to switch from stopping to lowering and from raising to stopping in a short time.

For this purpose, servo control can be used. In a press machine using servo control, the slide can be accelerated / decelerated / stopped by servo control of the servo motor rotation angle, so that the slide motion can be switched from ascending to stopping and from stopping to descending in a short time. A press machine using such servo control is described in Patent Document 1 below, for example.
JP 2005-271070 A "Press machine and press line"

  In general, a press machine is provided with a counter balance for supporting a slide against gravity. In this case, the slide is subjected to a force pulled downward by its own weight and a force lifted upward by the counter balance, but both are not normally balanced. Therefore, in a press machine using servo control, it is necessary to generate torque in the servo motor in order to hold the slide at the stop position. Therefore, current flows through the servo motor and heat is generated, so energy is wasted.

  Also, while the slide is stopped, servo control is performed so that the rotation angle of the servo motor matches the constant rotation angle corresponding to the slide stop position, but the servo motor is caused by a small difference between the constant rotation angle and the detected angle value. Repeat minute forward and reverse movements. Thereby, in the power transmission path from the servo motor to the slide, there is a possibility that the power transmission mechanism is deteriorated due to repeated contact between the gears.

  The problems of energy waste and power transmission mechanism degradation become particularly noticeable when the slide stop period is long. For example, when panel loading / unloading between molds is performed manually or by a low-speed transport device, the slide stop period becomes long, and the problems of waste of energy and deterioration of the power transmission mechanism become significant.

  Accordingly, an object of the present invention is a press machine using servo control, which can reduce power consumption when the slide is stopped, and transmit power by repeatedly contacting the tooth surface between gears by minute forward and reverse movements of the servo motor. An object of the present invention is to provide a press machine that can prevent the mechanism from deteriorating.

In order to achieve the above object, according to the present invention, an upper mold and a lower mold for pressing a workpiece in a vertical direction, a slide on which an upper mold is fixed to a lower surface and moved up and down, and the slide A press machine having a servo motor for raising and lowering, and a conversion mechanism for converting the rotary motion of the servo motor into a lift motion and transmitting it to the slide,
A control device that compares a command rotation angle value according to a slide motion pattern that gives a desired slide motion with a detected value of the rotation angle of the servo motor, and controls the rotation angle of the servo motor so as to follow the command rotation angle value; ,
A switching mechanism that is provided in the power transmission path from the servo motor to the slide and can be switched between a power transmission state in which the power from the servo motor is transmitted to the slide and a power non-transmission state in which the power from the servo motor is not transmitted to the slide When,
A slide holding mechanism that can move between a non-interfering position that does not interfere with the movement of the slide and a slide holding position that holds the slide at a fixed position;
Further, the control device stops the slide by controlling the rotation angle of a servo motor, then operates the slide holding mechanism to the slide holding position, and then switches the switching mechanism to a power non-transmission state. A press machine is provided.

In order to achieve the above object, according to the present invention, an upper mold and a lower mold for pressing a workpiece in a vertical direction, a slide on which the upper mold is fixed to the lower surface and moved up and down, A control method for a press machine, comprising: a servomotor for raising and lowering a slide; and a conversion mechanism for converting a rotary motion of the servomotor into a lifting motion and transmitting it to the slide,
A switching mechanism is provided in the power transmission path from the servo motor to the slide to switch between the power transmission state where the power from the servo motor is transmitted to the slide and the power non-transmission state where the power from the servo motor is not transmitted to the slide. ,
A slide holding mechanism is provided that can move between a non-interfering position that does not interfere with the movement of the slide and a slide holding position that holds the slide at a fixed position.
By comparing the command rotation angle value according to the slide motion pattern that gives the desired slide motion with the detection value of the rotation angle of the servo motor, and controlling the rotation angle of the servo motor to follow the command rotation angle value, Performing a press by lowering the slide, and then raising the slide to stop at the target stop position;
Moving the slide holding mechanism to the slide holding position after the slide has stopped at the target stop position;
And a step of switching the switching mechanism to a power non-transmission state.

In the press machine of the present invention and its control method, after the slide is stopped by controlling the rotation angle of the servo motor, the slide holding mechanism is moved to the slide holding position, and then the switching mechanism is in a power non-transmission state. To. Accordingly, since the slide is held by the slide holding mechanism when the slide is stopped, it is not necessary to supply the servo motor with a current for holding the slide at the stop position, and the servo motor and the slide are not transmitted with power. Since they are separated, the torque required for forward and reverse rotation of the servo motor is reduced, and as a result, the current supplied to the servo motor can be reduced. Therefore, power consumption when the slide is stopped can be reduced.
Further, when the slide is stopped, a minute repetitive forward / reverse motion of the servo motor is not transmitted to the power transmission path from the position where the power transmission from the servo motor 7 is disconnected by the switching mechanism to the slide. No repetitive movement occurs in. Therefore, in the power transmission path, it is possible to prevent the power transmission mechanism from being deteriorated due to repeated contact between the gears.
Therefore, the power consumption can be reduced while the slide is stopped, and the power transmission mechanism can be prevented from deteriorating due to repeated tooth contact at the meshing portion between the gears due to the forward / reverse rotation of the servo motor.

Further, the following advantages can be obtained by the press machine and the control method thereof.
(1) While the slide is stopped, the slide can be held at the stop position by the slide holding mechanism even if both are separated so that power is not transmitted from the servo motor to the slide.
(2) Since the slide holding mechanism is operated with respect to the stopped slide, friction and heat generation due to the braking action do not occur between the slide holding mechanism and the power transmission mechanism at the start of the operation. Further, during the slide holding period, the minute forward / reverse motion of the servo motor is not transmitted to the slide, so that friction and heat generation do not occur between the slide holding mechanism and the power transmission mechanism even during this period.
(3) Since the slide motion is controlled by the servo control as in the press machine using the conventional servo control, the slide motion can be shifted from rising to stopping, and the transition from stopping to lowering can be performed in a short time.
(4) Energy can be regenerated by changing the power supplied to the servomotor during slide deceleration, and energy use efficiency is high.

  According to the present invention described above, in a press machine using servo control, power consumption can be reduced while the slide is stopped, and the power transmission mechanism is deteriorated due to repeated tooth surface contact between gears due to minute forward and reverse movements of the servo motor. Can be prevented.

  The best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a configuration diagram of a press machine according to an embodiment of the present invention. As shown in FIG. 1, a press machine 10 includes an upper mold 3a and a lower mold 3b that press a workpiece 1 in a vertical direction, and a slide 5 on which the upper mold 3a is fixed to the lower surface and moved up and down. And a servo motor 7 for moving the slide 5 up and down, and a conversion mechanism 9 for converting the rotary motion of the servo motor 7 into a lift motion and transmitting it to the slide 5.

  The press machine 10 includes a control device 11, a switching mechanism 13, and a slide holding mechanism 15.

  The control device 11 compares the command rotation angle value according to a preset slide motion pattern with the detected rotation angle value of the servo motor 7 and controls the rotation angle of the servo motor 7 so as to follow the command rotation angle value. To do.

The switching mechanism 13 is provided in a power transmission path from the servo motor 7 to the slide 5, a power transmission state in which power from the servo motor 7 is transmitted to the slide 5, and power that does not transmit power from the servo motor 7 to the slide 5. Switch between non-transmission states. The switching mechanism 13 is switched to the power non-transmission state by the control device 11 after the slide 5 is stopped by controlling the rotation angle of the servo motor 7. As a mechanism for operating the switching mechanism 13 to a position corresponding to the power transmission state and a position corresponding to the power non-transmission state, a mechanism for operating the switching mechanism 13 directly by a solenoid driven by electromagnetic force, or a drive by electromagnetic force It is possible to use a mechanism that controls the hydraulic pressure and the pneumatic pressure by a solenoid that is operated, and operates the switching mechanism 13 by a hydraulic cylinder or a pneumatic cylinder.
In the example of FIG. 1, the switching mechanism 13 is a clutch. As the clutch, it is possible to use a dry or wet structure that transmits power by the frictional force between the friction plates, a structure that transmits power by meshing the mechanism, or the like.

The slide holding mechanism 15 is movable between a non-interference position that does not interfere with the movement of the slide 5 and a slide holding position that holds the slide 5 at a fixed position. The slide holding mechanism 15 is driven to the slide holding position by the control device 11 after the slide motion is stopped and the switching mechanism 13 is switched to the power non-transmission state. As a mechanism for operating the slide holding mechanism 15 between the non-interference position and the slide holding position, a mechanism for directly operating the slide holding mechanism 15 by a solenoid driven by electromagnetic force, or a hydraulic pressure or air pressure by a solenoid driven by electromagnetic force. A mechanism for controlling and operating the slide holding mechanism 15 by a hydraulic cylinder or a pneumatic cylinder can be used.
In the example of FIG. 1, the slide holding mechanism 15 is a mechanical brake. As a mechanical brake, a disc brake that presses a pad against a brake disc, a brake that tightens a drum with a band, or the like can be used.

  The configuration of the control device 11 will be described in detail. The control device 11 includes a press machine controller 11a, a servo controller 11b, and a motor drive amplifier 11c.

The press machine controller 11a outputs a command rotation angle value according to a preset slide motion pattern. The slide motion pattern defines a command rotation angle value (corresponding to a slide position) with respect to time, and the press machine controller 11a determines the servo motor 7 corresponding to the time based on the slide motion pattern at each time. Outputs the command rotation angle value. A detected rotation angle value is input to the press controller from a motor rotation angle encoder 17 that detects the rotation angle of the servo motor 7.
Further, the press machine controller 11a outputs a clutch connection command to the clutch 13, connects the output shaft of the servo motor 7 and an input shaft of the speed reducer 21, which will be described later, to place the clutch 13 in a power transmission state, and issues a clutch disconnection command. It outputs to the clutch 13 and the output shaft of the servo motor 7 and the input shaft of the speed reducer 21 are disconnected, and the clutch 13 is brought into a power non-transmission state.
The press machine controller 11 a outputs a brake operation command to the brake 15, operates the brake 15 to a position where the slide 5 is held at the stop position, outputs a brake non-operation command to the brake 15, and moves the slide 5. The brake 15 is operated to a position where it does not interfere with.
The press machine controller 11a can be configured by a relay circuit, a digital logic circuit, a programmable logic controller PLC, or the like.

The servo controller 11b compares the detected rotation angle of the servo motor 7 from the motor rotation angle encoder 17 with the command rotation angle value from the press machine controller 11a, and sets the rotation angle of the servo motor 7 to the command rotation angle value. The command value to be followed is output.
As a control method of the servo controller 11b, a configuration in which feedback control such as PI, PID, and IPD is combined with feedforward control as necessary can be used.

The motor drive amplifier 11c is electrically connected to the servo motor 7, and can change the current and voltage supplied to the servo motor 7, thereby changing the torque and the rotational speed of the servo motor 7. The motor drive amplifier 11c receives a command value from the servo controller 11b, supplies current and voltage according to the command value to the servo motor 7, and thereby moves the slide 5 according to the slide motion pattern.
As the motor drive amplifier 11c, a PWM inverter using a power MOSFET or IGBT is used when the AC servomotor 7 is used, and a chopper system using thyristor Leonard or IGBT is used when the DC servomotor 7 is used. Can be used. Further, by using a configuration capable of energy regeneration such as a four-quadrant control inverter as the motor drive amplifier 11c, the kinetic energy is converted and recovered into electric energy when the servo motor 7 is decelerated, thereby reducing energy loss. Can do.

As the servo motor 7, an induction motor, a synchronous motor, a direct current motor, or the like can be used.
As the motor rotation angle encoder 17, an optical encoder or a resolver can be used.
In the example of FIG. 1, a crankshaft rotation angle encoder 19 for detecting a rotation angle of a crankshaft 9a, which will be described later, is provided, and the detected crankshaft rotation angle from the crankshaft rotation angle encoder 19 is input to the press machine controller 11a. Is done. Since the dimensions and shapes of the crankshaft 9a and the connecting rod 9b are known, the crankshaft rotation angle and the slide height can be mutually converted by calculation. Therefore, the crankshaft rotation angle input to the press machine controller 11a can be used for operation confirmation. As the crankshaft rotation angle encoder 19, an optical encoder or a resolver can be used.

  The configuration of other parts of the press machine 10 will be described.

  The rotation of the servo motor 7 is transmitted to the speed reducer 21 via the clutch 13. The rotation is decelerated by the speed reducer 21, and the crankshaft 9 a is rotated by the output from the speed reducer 21. The crankshaft 9a and the slide 5 are mechanically connected by a connecting rod 9b. When the crankshaft 9a rotates, the slide 5 moves up and down. As the speed reducer 21, for example, a mechanism for meshing spur teeth or bevel gears having different numbers of teeth can be used.

  The lower mold 3b is attached to the bolster 23. During the press working, the load acting on the upper mold 3a is supported on the upper part of the frame 25 via the slide 5, the connecting rod 9b and the crankshaft 9a, and the load acting on the lower mold 3b is supported via the bolster 23 on the frame 25. Supported at the bottom. The workpiece 1 to be press-molded is inserted between the upper die 3a and the lower die 3b, the slide 5 is lowered, and the workpiece 1 comes into contact with the upper die 3a and the lower die 3b. The press molding force acts on the workpiece 1 from the upper mold 3a and the lower mold 3b.

  A counter balance 27 is provided to support the weight of the slide 5 and the upper mold 3a. As the mechanism of the counter balance 27, as shown in FIG. 1, an air type that pushes up the piston 27a with compressed air in the cylinder can be used.

  Next, a method for controlling the press machine 10 having the above-described configuration will be described. FIG. 2 is a flowchart showing a control method of the press machine 10.

  In step S1, in the state where the slide 5 is stopped, the press start preparation is performed. The press machine controller 11a of the control device 11 outputs a power transmission command to the switching mechanism 13 (the clutch in the example of FIG. 1) in the power non-transmission state / position where the power is not transmitted from the servo motor 7 to the slide 5 and switched. The mechanism 13 is switched and moved to the power transmission state / position. Next, the press machine controller 11a outputs a holding release command to the slide holding mechanism 15 (brake in the example of FIG. 1) at the slide holding position, and moves the slide holding mechanism 15 to the non-interference position. In step S1, the control device 11 continuously performs servo control for maintaining the servo motor 7 at a constant rotation angle.

In step S2, the slide 5 is moved up and down to perform pressing. The control device 11 performs control of lowering the slide 5 to press the workpiece 1 and then raising the slide 5 again to stop at the target stop position. During this period, as described above, the press machine controller 11a of the control device 11 outputs a command rotation angle value according to a preset slide motion pattern, and the motor rotation angle encoder 17 determines the detected rotation angle of the servo motor 7. Output. The servo controller 11b of the control device 11 compares the command rotation angle value with the detected rotation angle value, and controls the rotation angle of the servo motor 7 via the motor drive amplifier 11c so as to follow the command rotation angle value. To do. During this period, the vertical movement / acceleration / deceleration of the slide 5 is performed by the servo motor 7. Therefore, by using the motor drive amplifier 11c capable of power regeneration, energy regeneration is performed when the servo motor 7 decelerates, and energy loss is reduced. Can be small.
In order to keep the slide 5 at the stop position, the press machine controller 11a outputs a constant command angle value corresponding to the slide stop position, and the servo controller 11b matches the rotation angle of the servo motor 7 with this constant command angle value. To control. Thereby, the slide 5 is held at the target stop position.
The target stop position may be a position where the crankshaft 9a and the connecting rod 9b are highest, that is, the top dead center of the slide 5, or a position other than that.

  In step S3, after the slide 5 is stopped at the target stop position as described above, the press machine controller 11a outputs a slide holding command to the slide holding mechanism 15 to output the slide holding mechanism 15 (brake in the example of FIG. 1). Is moved to the slide holding position. Thereby, the slide 5 is held at the target stop position.

Next, in step S4, the press machine controller 11a outputs a power non-transmission command (clutch disengagement command) to the switching mechanism 13 (a clutch in the example of FIG. 1). Switch to the disconnected state. As a result, the slide 5 is held at the target stop position by the slide holding force of the slide holding mechanism 15 in a state where the driving force of the servo motor 7 is not transmitted to the slide 5. Accordingly, since the servo motor 7 is in a state of driving only the servo motor 7 itself, a minute forward / reverse motion by servo control is repeated due to a minute difference between a constant command rotation angle value and a detected angle value. Only a small torque needs to be generated. As a result, the current flowing through the servomotor 7 and the motor drive amplifier 11c is reduced.
While the slide is stopped in step S4, the workpiece 1 that has been pressed is removed by manual operation or an automatic conveyance device, and a new workpiece 1 is placed on the lower mold 3b. Then, it returns to step S1. In this way, the pressing cycle is repeated.

  In the above press working cycle, the crankshaft rotation angle detected by the crankshaft rotation angle encoder 19 is input to the press machine controller 11a and used for confirming the operation. That is, when the switching mechanism 13 is in the power transmission state, the rotation angle of the servo motor 7 and the rotation angle of the crankshaft 9a should change at the same ratio as the reduction ratio of the reduction gear 21, so that the press machine controller 11a The rotation angle detected by the motor rotation angle encoder 17 and the rotation angle detected by the crankshaft rotation angle encoder 19 are compared, and if it does not change at the same ratio as the reduction ratio of the speed reducer 21, it is determined as abnormal. Since the crankshaft 9a should not rotate when the slide holding mechanism 15 is in the slide holding position, the press machine controller 11a checks whether the crankshaft rotation angle does not change, and if it changes, determines that it is abnormal. As an operation in the case where an abnormality is determined, a slide holding mechanism 15 (brake) that stops the servo motor 7 while maintaining the command rotation angle value at a constant value, puts the switching mechanism 13 (clutch) into a non-power transmission state, and There are operations such as moving to a slide holding position, cutting a circuit (not shown) that supplies power to the motor drive amplifier 11c, and combinations thereof.

In the press machine 10 and the control method thereof according to the above-described embodiment of the present invention, after the slide 5 is stopped by controlling the rotation angle of the servo motor 7, the slide holding mechanism 15 is moved to the slide holding position, and then the switching mechanism. 13 is in a power non-transmission state. Accordingly, since the slide 5 is held by the slide holding mechanism 15 in the stop state of the slide 5, it is not necessary to supply the servo motor 7 with a current for holding the slide 5 in the stop position, and the servo motor 7 and the slide Therefore, the torque required for forward / reverse rotation of the servo motor 7 is reduced, and as a result, the current supplied to the servo motor 7 can be reduced. Therefore, power consumption when the slide is stopped can be reduced.
In addition, during the slide stop, the minute repetitive forward / reverse motion of the servo motor 7 is not transmitted to the power transmission path from the portion where the power transmission from the servo motor 7 is disconnected by the switching mechanism 13 to the slide 5. In the power transmission path, minute repetitive motion does not occur. Therefore, in the power transmission path, it is possible to prevent the power transmission mechanism from being deteriorated due to repeated contact between the gears.
Therefore, the power consumption can be reduced while the slide is stopped, and the power transmission mechanism can be prevented from deteriorating due to repeated tooth contact at the meshing portion between the gears due to the forward / reverse motion of the servo motor 7.

Further, the following advantages can be obtained by the press machine 10 and the control method thereof according to the embodiment of the present invention.
(1) While the slide is stopped, the slide 5 can be held at the stop position by the slide holding mechanism 15 even if they are separated so that power is not transmitted from the servo motor 7 to the slide 5.
(2) Since the slide holding mechanism 15 is operated with respect to the stopped slide 5, friction and heat generation due to a brake action do not occur between the slide holding mechanism 15 and the power transmission mechanism at the start of the operation. Further, during the slide holding period, the minute forward / reverse motion of the servo motor 7 is not transmitted to the slide 5, so that friction and heat generation do not occur between the slide holding mechanism 15 and the power transmission mechanism even during this period.
(3) Since the slide motion is controlled by servo control in the same manner as a press machine using conventional servo control, the slide motion can be shifted from ascending to stopped, and the transition from stopping to descending can be performed in a short time.
(4) It is possible to regenerate energy by changing the power supplied to the servo motor 7 during slide deceleration, and energy use efficiency is high.

  The present invention is not limited to the above-described embodiment, and various changes can be made without departing from the scope of the present invention.

  For example, in the example of FIG. 1, the clutch 13 and the mechanical brake 15 are provided on the high speed shaft side of the speed reducer 21, that is, between the servo motor 7 and the speed reducer 21. Are provided on the low speed shaft side of the speed reducer 21, that is, between the speed reducer 21 and the connecting rod 9b, the clutch 13 is on the high speed shaft side of the speed reducer 21, and the mechanical brake 15 is on the speed reducer 21. A configuration provided on the low-speed shaft side is also possible.

  In addition, the crankshaft 9a and the connecting rod 9b constitute the conversion mechanism 9, but a conversion mechanism that converts the rotational motion into a lifting motion other than the crank type, such as a link type, a knuckle type, or a cranceless type, may be configured.

  In the example of FIG. 1, a mechanism for supporting the slide 5 at one point is shown, but a mechanism for supporting at a plurality of points such as two-point support and four-point support may be used.

  Although the configuration of one servo motor 7 is shown, a plurality of servo motors 7 may be used. In the case where the plurality of servo motors 7 drive one crankshaft 9a, only one set of the clutch 13 and the mechanical brake 15 may be provided between the plurality of servomotors 7 and the crankshaft 9a. A clutch 13 and a mechanical brake 15 may be provided for each servo motor 7 between the servo motor 7 and the crankshaft 9a. In the case where a plurality of servo motors 7 are configured to drive independent crankshafts 9a for each one, a clutch 13 and a mechanical brake 15 may be provided for each servo motor 7.

In the example of FIG. 1, the rotation angle detection means of the servomotor 7 is the motor rotation angle encoder 17, but other detection means may be used.
For example, in the state where the clutch 13 is connected, the servo motor by the servo controller 11b uses the crankshaft rotation angle detected by the crankshaft rotation angle encoder 19 instead of the motor rotation angle detected by the motor rotation angle encoder 17. 7 servo control may be performed.
Further, a sensor for directly detecting the position of the slide 5 such as a linear scale may be provided, and the detected value of the slide position from the sensor may be used for controlling the rotation angle of the servo motor 7 by the servo controller 11b. In this case, the rotation angle of the servo motor 7 may be controlled by converting the slide position into the rotation angle of the servo motor 7 or vice versa. The slide position detection value from the sensor may be used for operation confirmation instead of the crankshaft rotation angle detected by the crankshaft rotation angle encoder 19.

  In the example of FIG. 1, the slide holding mechanism 15 is a mechanical brake, but may be another appropriate mechanism that holds the slide 5 at the stop position. For example, as shown in FIG. 3, the slide holding mechanism 15 is engaged with gear teeth provided in the middle of a power transmission path for transmitting power from the servo motor 7 to the slide 5 to hold the slide 5 in the stop position. It may be a mechanism that can move between a position where it engages and a position where it does not engage.

  In the example of FIG. 1, the slide motion pattern set in advance is a “slide motion pattern that gives a desired slide motion” that is used for controlling the rotation angle of the servomotor 7, but the present invention is not limited to this. That is, the slide motion pattern may be changed according to various conditions such as the progress of the press working of the work material and the movement of the work material carrying-in / out device. For example, the deformation state of the panel may be measured momentarily during press molding, and the slide motion pattern may be changed accordingly. In such a case, the changed slide motion pattern may be a “slide motion pattern that gives a desired slide motion”.

It is a block diagram of the press machine by embodiment of this invention. It is a flowchart which shows the control method of the press machine by embodiment of this invention. It is a figure which shows the other structural example of a slide holding mechanism.

Explanation of symbols

1 Work material 3a Upper mold
3b Lower mold 5 Slide 7 Servo motor 9 Conversion mechanism 9a Crankshaft 9b Connecting rod 10 Press machine 11 Controller 11a Press machine controller 11b Servo controller 11c Motor drive amplifier 13 Switching mechanism (clutch)
15 Slide holding mechanism (mechanical brake)
17 Motor rotation angle encoder 19 Crankshaft rotation angle encoder 21 Reducer 23 Bolster 25 Frame 27 Counter balance 27a Piston

Claims (2)

Upper mold and lower mold for pressing the workpiece in the vertical direction, a slide on which the upper mold is fixed to the lower surface and moved up and down, a servo motor for moving the slide up and down, and rotation of the servo motor A press mechanism having a conversion mechanism that converts the motion into a lifting motion and transmits it to the slide,
A control device that compares a command rotation angle value according to a slide motion pattern that gives a desired slide motion with a detected value of the rotation angle of the servo motor, and controls the rotation angle of the servo motor so as to follow the command rotation angle value; ,
A switching mechanism that is provided in the power transmission path from the servo motor to the slide and can be switched between a power transmission state in which the power from the servo motor is transmitted to the slide and a power non-transmission state in which the power from the servo motor is not transmitted to the slide When,
A slide holding mechanism that can move between a non-interfering position that does not interfere with the movement of the slide and a slide holding position that holds the slide at a fixed position;
Further, the control device stops the slide by controlling the rotation angle of a servo motor, then operates the slide holding mechanism to the slide holding position, and then switches the switching mechanism to a power non-transmission state. Press machine. Upper mold and lower mold for pressing the workpiece in the vertical direction, a slide on which the upper mold is fixed to the lower surface and moved up and down, a servo motor for moving the slide up and down, and rotation of the servo motor A control mechanism for converting a movement into a lifting movement and transmitting it to the slide,
A switching mechanism is provided in the power transmission path from the servo motor to the slide to switch between the power transmission state where the power from the servo motor is transmitted to the slide and the power non-transmission state where the power from the servo motor is not transmitted to the slide. ,
A slide holding mechanism is provided that can move between a non-interfering position that does not interfere with the movement of the slide and a slide holding position that holds the slide at a fixed position.
By comparing the command rotation angle value according to the slide motion pattern that gives the desired slide motion with the detection value of the rotation angle of the servo motor, and controlling the rotation angle of the servo motor to follow the command rotation angle value, Performing a press by lowering the slide, and then raising the slide to stop at the target stop position;
Moving the slide holding mechanism to the slide holding position after the slide has stopped at the target stop position;
And a step of switching the switching mechanism to a power non-transmission state.

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