JP6240367B1 - Die cushion control device and die cushion control method - Google Patents

Abstract

A die cushion control device and a die cushion control method for safely and speedily performing adjustment confirmation of a die cushion control device that controls a die cushion device main body. A die cushion control device 200 includes a die cushion simulator 230 that models a die cushion device main body, and can select whether to drive the die cushion device main body (actual machine) or to drive the die cushion simulator 230. To. When the drive of the die cushion apparatus main body is selected, the die cushion pressure controller 200 functions as usual. When the drive of the die cushion simulator 230 is selected, a signal necessary for the simulation is sent to the die cushion simulator 230. The simulation result is obtained using the die cushion simulator 230 instead of the actual die cushion device main body, and the adjustment of the die cushion control device can be confirmed. [Selection] Figure 2

Description

  The present invention relates to a die cushion control device and a die cushion control method, and more particularly, to a technique for performing adjustment confirmation of a die cushion control device that controls a die cushion device main body safely and speedily.

  Conventionally, in a press machine having a die cushion device main body, a servo motor that drives a hydraulic pump connected to the head side hydraulic chamber is used for the hydraulic pressure (die cushion force) of the head side hydraulic chamber of the hydraulic cylinder that supports the cushion pad. There is known a servo die cushion device that is controlled (Patent Document 1).

  On the other hand, Patent Document 2 describes a drive control device for a servo motor provided with simulation means. The simulation means described in Patent Document 2 is for confirming the function of the position control device of a single servo motor without actually driving the servo motor. The simulation means inputs a command signal to the servo motor. The detection output (rotational position signal) of the position detecting means (encoder) for detecting the rotational position of the servo motor is calculated.

  Patent Document 3 describes a molding condition determination system that determines optimal molding conditions without actually repeating trial manufacture of a molded product using a press machine. The molding condition determination system described in Patent Document 3 is for the purpose of pursuing drawability, and the material drawing (plasticity associated with molding) deformation condition is changed to multiple types of molding conditions (slide speed and die cushion pressure of the press machine). To the molding simulation means, and the optimum molding conditions are determined based on the analysis result of the molding simulation means.

JP 2006-315074 A JP-A-5-127750 JP 2008-178889 A

  In general, a die cushion device that functions by being struck by a press machine (that generates a predetermined force in the opposite direction of being struck while being struck) is a fragile machine. In particular, the servo die cushion device described in Patent Document 1 including complicated control elements is more prone to the problem, and there is a problem that the manufacturer tends to fail in the function (control) construction process. In addition, the user has a problem that not only the apparatus but also the mold may be damaged if an incorrect operation is performed on the servo die cushion apparatus or an erroneous setting is performed.

  However, there is no appropriate and reliable method for dealing with the above problem, and there is no method other than checking the function of the die cushion control device alone in advance.

  On the other hand, the servo motor drive control device (simulation means) described in Patent Document 2 relates to position control (simulation) of a servo motor, which is a simple element (not a system composed of a plurality of elements). It is not related to position control (for example, force control), it does not take into account the effect of externally acting force that causes the slide of the press machine to collide, and is self-contained (the motor position controller controls the motor (Move) to operate. According to the simulation means described in Patent Document 2, although there is an advantage that the manufacturer can confirm the basic function of the position controller without actually driving the servo motor, there is no advantage for the user.

  In addition, the molding condition determination system described in Patent Document 3 simulates material drawing (plasticity accompanying molding) deformation by applying a slide speed and die cushion pressure for the purpose of pursuing drawability. It is not intended for the response waveform of the die cushion force, nor is it performed in real time.

  The present invention has been made in view of such circumstances, and provides a die cushion control device and a die cushion control method capable of safely and speedily performing adjustment confirmation of a die cushion control device that controls the die cushion device main body. The purpose is to do.

  In order to achieve the above object, one aspect of the present invention includes a cushion pad, a hydraulic cylinder that supports the cushion pad and generates a die cushion force when the press machine slides down, and drives the hydraulic cylinder. A hydraulic pump / motor for generating pressure fluid to perform, a servo motor connected to the rotary shaft of the hydraulic pump / motor, and a pressure for detecting the pressure in the pressure chamber on the cushion pressure generation side of the hydraulic cylinder A die cushion control device that controls a die cushion device main body having a detector and a drive unit that drives the servo motor based on a first torque command signal that is input, wherein a die cushion pressure set in advance is set. A die cushion pressure command device for outputting a die cushion pressure command signal, and a first drive mode for driving the die cushion device main body. Or a drive mode selector that selects a second drive mode for driving a die cushion simulator that models the die cushion apparatus main body, and the first drive mode is selected by the drive mode selector. Based on the die cushion pressure command signal and a first die cushion pressure signal indicating the pressure detected by the pressure detector, a cushion pressure generation side pressurizing chamber of the hydraulic cylinder detected by the pressure detector. The first torque command signal is set to a pressure corresponding to the die cushion pressure command signal, the generated first torque command signal is output to the die cushion device body, and the drive mode selection is performed. When the second drive mode is selected by the device, the die cushion pressure command signal and the die cushion simulation are selected. On the cushion pressure generation side of the hydraulic cylinder calculated by the die cushion simulator on the basis of the second die cushion pressure signal indicating the pressure in the pressure chamber on the cushion pressure generation side of the hydraulic cylinder calculated by the cylinder Die cushion pressure control for generating a second torque command signal for setting the pressure in the pressurizing chamber to a pressure corresponding to the die cushion pressure command signal, and outputting the generated second torque command signal to the die cushion simulator A die cushion that outputs at least the second die cushion pressure signal from a physical quantity calculated based on a controller, at least the second torque command signal and a slide position signal indicating a slide position of the press machine When the first drive mode is selected by a simulator and the drive mode selector, The first die cushion pressure signal detected by the pressure detector is input to the die cushion pressure controller, and the first torque command signal is output to the die cushion device body, and the drive mode selector When the second drive mode is selected by the above, the second die cushion pressure signal calculated by the die cushion simulator is input to the die cushion pressure controller, and the second torque command signal is input to the die cushion pressure controller. An input / output selector for outputting to the die cushion simulator.

  According to one aspect of the present invention, it is possible to select whether to drive the die cushion device main body (actual machine) or the die cushion simulator, and when the drive of the die cushion device main body is selected, the die cushion is selected. The pressure controller will function normally. That is, the die cushion pressure controller generates a first torque command signal based on the die cushion pressure command signal and the first die cushion pressure signal indicating the pressure detected by the pressure detector, and generates the generated first torque command signal. Torque command signal is output to the die cushion device body, and the die cushion device body is driven. On the other hand, when the drive of the die cushion simulator is selected, the die cushion pressure controller operates in the same manner as when the drive of the die cushion device main body is selected, but the first cushion detected in the die cushion device main body is detected. A second torque command signal is generated using the second die cushion pressure signal calculated by the die cushion simulator instead of the die cushion pressure signal, and the generated second torque command signal is output to the die cushion simulator. Then, the die cushion simulator is driven. Therefore, using the die cushion simulator instead of the actual die cushion device main body, the function confirmation of the die cushion control device (including debugging of the die cushion control device having a control algorithm) can be reliably performed, and safety is ensured. In addition, operation adjustment can be performed speedily. In addition, the die cushion pressure (force) can be accurately predicted using the die cushion simulator, and the die cushion force related setting values (for example, die cushion force, preliminary acceleration level (impact) The degree of die cushion force (rising response, overshoot / undershoot, etc.) that occurs against the degree of acceleration (downward acceleration before) and the degree of control compensation that suppresses surge and stabilizes control) It is possible to adjust (adjust while confirming) safely and speedily without using a mold (without applying an extra load to the mold).

  In the die cushion control device according to another aspect of the present invention, when the second drive mode is selected by the drive mode selector, at least the second die cushion pressure signal calculated by the die cushion simulator or Based on the second die cushion pressure signal calculated from the second die cushion pressure signal, the second die cushion pressure signal or the second die cushion pressure signal corresponding to the second die cushion pressure signal or the second die cushion pressure signal is calculated. It is preferable to include an output unit that displays the die cushion force of 2 on the display unit and / or records it on the recording unit.

  The simulation algorithm (at least the second die cushion pressure or the second die cushion force) by the die cushion simulator is displayed on the display unit and / or recorded in the recording unit, thereby confirming the simulation result and controlling algorithm. , Etc., human error elimination, die cushion force related setting value correction, and the like can be performed.

  In the die cushion control device according to still another aspect of the present invention, when the first drive mode is selected by the drive mode selector, the output unit detects at least a first detected by the pressure detector. Based on the first die cushion pressure signal or the first die cushion pressure signal calculated from the first die cushion pressure signal, the first die cushion pressure signal or the first die cushion force signal corresponding to the first die cushion pressure signal is calculated. It is preferable that the die cushion pressure or the first die cushion force is displayed on the display unit and / or recorded on the recording unit.

  The operation result when driving the actual die cushion device main body (at least the first die cushion pressure or the first die cushion force) is displayed on the display unit and / or recorded in the recording unit, whereby the operation result is displayed. The set value related to the die cushion force can be corrected while confirming.

  In the die cushion control device according to still another aspect of the present invention, the die cushion device main body includes an angular velocity detector for detecting an angular velocity of the servo motor, and the die cushion pressure controller is configured in the drive mode. When the first drive mode is selected by the selector, the die cushion pressure command signal, the first die cushion pressure signal indicating the pressure detected by the pressure detector, and the angular velocity detector detected by the angular velocity detector. Based on the first angular velocity signal indicating the angular velocity of the servo motor, the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder detected by the pressure detector is a pressure corresponding to the die cushion pressure command signal. The first torque command signal is generated, and the generated first torque command signal is output to the die cushion device body. When the second drive mode is selected by the drive mode selector, the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder calculated by the die cushion pressure command signal and the die cushion simulator is calculated. Cushion pressure generation of the hydraulic cylinder calculated by the die cushion simulator based on a second die cushion pressure signal shown and a second angular speed signal showing the angular velocity of the servomotor calculated by the die cushion simulator Generating a second torque command signal for setting the pressure in the side pressurizing chamber to a pressure corresponding to the die cushion pressure command signal, and outputting the generated second torque command signal to the die cushion simulator; The cushion simulator includes at least the second torque command signal and the pre- Among the physical quantities calculated based on the slide position signal indicating the position of the machine slide, at least the second die cushion pressure signal and the second angular velocity signal are output, respectively, and the input / output selector When the first drive mode is selected by the drive mode selector, the first die cushion pressure signal detected by the pressure detector and the first angular velocity signal detected by the angular velocity detector are When the die cushion pressure controller is input and the first torque command signal is output to the die cushion device main body, and the second drive mode is selected by the drive mode selector, the die cushion simulator The calculated second die cushion pressure signal and the second angular velocity signal are used as the die cushion pressure controller. Preferably, the second torque command signal is output to the die cushion simulator.

  According to still another aspect of the present invention, the die cushion pressure controller further uses the first angular velocity signal indicating the angular velocity of the servomotor detected by the angular velocity detector, and uses the first torque command. When the second drive mode is selected by the drive mode selector, the second torque command signal is further generated by using the second angular velocity signal calculated by the die cushion simulator. Therefore, the die cushion pressure (force) of the die cushion apparatus main body can be controlled with high accuracy, and the die cushion pressure (force) can be accurately simulated with the die cushion simulator.

  In the die cushion control device according to still another aspect of the present invention, the die cushion simulator preferably digitally calculates the second die cushion pressure signal and the second angular velocity signal. The die cushion simulator digitally calculates the second die cushion pressure signal and the second angular velocity signal, respectively, and is not limited to linear elements (gain, first-order lag element, integral element), and cannot be calculated by an analog circuit. An operation including a non-linear element is possible.

  In the die cushion control device according to still another aspect of the present invention, the die cushion simulator preferably calculates the second die cushion pressure signal and the second angular velocity signal in real time. The die cushion simulator calculates the second die cushion pressure signal and the second angular velocity signal in real time, and allows the second torque command signal to be input in real time. The die cushion pressure controller can be shared between the case of the die cushion device main body and the case of the die cushion simulator.

  In the die cushion control device according to still another aspect of the present invention, it is preferable that the die cushion simulator includes linear elements and nonlinear elements that are physically equivalent to the die cushion apparatus body. Since the die cushion apparatus main body is an aggregate of a plurality of elements including linear elements and nonlinear elements, the die cushion simulator is also physically equivalent including linear elements and nonlinear elements.

  In the die cushion control device according to still another aspect of the present invention, the die cushion pressure controller is detected by the pressure detector when the first drive mode is selected by the drive mode selector. The first die cushion pressure signal is used as a pressure feedback signal, and the first angular velocity signal detected by the angular velocity detector is used as the dynamic stability of the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder. When the second drive mode is selected by the drive mode selector, the second die cushion pressure signal calculated by the die cushion simulator is used as a pressure feedback. The second angle used as a signal and calculated by the die cushion simulator The degree signal, is preferably used as an angular velocity feedback signal for ensuring the dynamic stability of the pressure cushion pressure generation side pressure chamber of the hydraulic cylinder which is calculated by said die cushion simulator.

  In the die cushion control device according to still another aspect of the present invention, a press simulator that models the press machine, the slide position of the press machine based on a slide position command signal input from a slide position commander, and The press simulator for calculating a slide position signal indicating a speed and a slide speed signal is provided, and the input / output selector calculates by the press simulator when the second drive mode is selected by the drive mode selector. It is preferable to input the slide position signal and the slide speed signal that have been input to the die cushion simulator. When the second drive mode is selected by the drive mode selector, the slide position signal and the slide speed signal calculated by the press simulator can be used in the die cushion simulator. Thus, the die cushion device main body can be simulated without operating the press machine as well as the die cushion device main body.

  In the die cushion control device according to still another aspect of the present invention, the die cushion pressure controller further inputs a slide position signal and a slide speed signal indicating a slide position and a speed of the press machine, and the input slide. It is preferable that the position signal and the slide speed signal are used for generating the first torque command signal and the second torque command signal.

  In the die cushion control device according to still another aspect of the present invention, a press simulator that models the press machine, the slide position of the press machine based on a slide position command signal input from a slide position commander, and The press simulator for calculating a slide position signal and a slide speed signal indicating speed, respectively, and the input / output selector slides the press machine when the first drive mode is selected by the drive mode selector. The slide position signal and the slide speed signal detected by the slide position detector and the slide speed detector, respectively, for detecting the position and speed, are input to the die cushion pressure controller, and the drive mode selector selects the second When the driving mode is selected, the press simulator It is preferable to enter more calculated the slide position signal and the slide speed signal to the die cushion pressure controller.

  The die cushion control apparatus which concerns on the further another aspect of this invention WHEREIN: The die cushion position command device which outputs the die cushion position command signal which shows the position of the said cushion pad, and the die cushion position detector which detects the position of the said cushion pad When the first drive mode is selected by the drive mode selector, the die cushion position command signal and the die cushion position detector are detected when the slide is in the non-molding region. Based on the first die cushion position signal indicating the position of the cushion pad, the position of the cushion pad detected by the die cushion position detector is set to a position corresponding to the die cushion position command signal. 1 torque command signal is generated, and the generated first torque command signal is When the second drive mode is selected by the drive mode selector and the slide is in the non-molding process region, the die cushion position command signal and the die cushion simulator are output to the cushion device body. The position of the cushion pad calculated by the die cushion simulator is set to a position corresponding to the die cushion position command signal based on the second die cushion position signal indicating the position of the cushion pad calculated by A die cushion position controller that generates a second torque command signal and outputs the generated second torque command signal to the die cushion simulator, and the die cushion simulator includes at least the die cushion position controller. Based on the output second torque command signal When the first drive mode is selected by the drive mode selector, the input / output selector outputs at least the second die cushion position signal from the physical quantity to be calculated. A die cushion position signal is input to the die cushion position controller, and the first torque command signal generated by the die cushion position controller is output to the die cushion apparatus body, and the drive mode selector When the second drive mode is selected, the second die cushion position signal is input to the die cushion position controller, and the second torque command signal generated by the die cushion position controller is It is preferable to output to a die cushion simulator.

  According to still another aspect of the present invention, the die cushion position controller further includes a die cushion position controller, and when the first drive mode is selected by the drive mode selector, the die cushion device body A first torque command signal for controlling the position of the cushion pad of the die cushion simulator is generated, and when the second drive mode is selected by the drive mode selector, the position of the cushion pad of the die cushion simulator is controlled. A second torque command signal is generated. Further, the die cushion simulator is configured to at least the second die cushion position based on the second torque command signal output from the die cushion position controller when the slide is in a non-molding process region. Calculate the signal. That is, the position of the cushion pad of the die cushion device body can be controlled, and the position of the cushion pad of the die cushion simulator can be controlled.

  In the die cushion control device according to still another aspect of the present invention, the die cushion device main body includes an angular velocity detector for detecting an angular velocity of the servo motor, and the die cushion position controller is configured in the drive mode. When the first drive mode is selected by the selector, when the slide is in the non-molding step region, the cushion pad command signal and the cushion pad detected by the die cushion position detector are detected. Based on the first die cushion position signal indicating the position and the first angular velocity signal indicating the angular velocity of the servomotor detected by the angular velocity detector, the cushion pad detected by the die cushion position detector. A first torque command signal is generated so that the position corresponds to the die cushion position command signal. When the generated first torque command signal is output to the die cushion device main body and the second drive mode is selected by the drive mode selector, the slide is in the non-molding process region. Is a second die cushion position signal indicating the position of the cushion pad calculated by the die cushion position command signal, the die cushion simulator, and an angular velocity of the servo motor calculated by the die cushion simulator. Based on the angular velocity signal, a second torque command signal is generated for setting the position of the cushion pad calculated by the die cushion simulator to a position corresponding to the die cushion position command signal, and the generated second torque A command signal is output to the die cushion simulator, and the die cushion is The simulator outputs at least the second die cushion position signal and the second angular velocity signal among physical quantities calculated based on at least the second torque command signal output from the die cushion position controller. When the first drive mode is selected by the drive mode selector, the input / output selector sends the first die cushion position signal and the first angular velocity signal to the die cushion position controller. When the first torque command signal generated by the die cushion position controller is output to the die cushion device main body and the second drive mode is selected by the drive mode selector, The second die cushion position signal and the second angular velocity signal are input to the die cushion position controller, and the It is preferable to cause the die cushion simulator to output the second torque command signal generated by the cushion position controller.

  According to still another aspect of the present invention, the die cushion position controller further uses the first angular velocity signal indicating the angular velocity of the servomotor detected by the angular velocity detector, and uses the first torque command. When the second drive mode is selected by the drive mode selector, the second torque command signal is further generated by using the second angular velocity signal calculated by the die cushion simulator. Therefore, the position of the cushion pad of the die cushion device main body can be controlled with high accuracy, and the simulation of the position of the cushion pad by the die cushion simulator can be performed with high accuracy.

  In the die cushion control device according to still another aspect of the present invention, the die cushion position controller is detected by the die cushion position detector when the first drive mode is selected by the drive mode selector. Further, the first die cushion position signal is used as a position feedback signal, and the first angular velocity signal detected by the angular velocity detector is used as an angular velocity feedback for ensuring the dynamic stability of the cushion pad position. And when the second drive mode is selected by the drive mode selector, the second die cushion position signal calculated by the die cushion simulator is used as a position feedback signal, and the die The second angular velocity signal calculated by the cushion simulator It is preferred to use as an angular velocity feedback signal for ensuring the dynamic stability of the position of the cushion pad, which is calculated by said die cushion simulator.

  Still another aspect of the present invention includes a cushion pad, a hydraulic cylinder that supports the cushion pad and generates a die cushion force when the slide of the press machine is lowered, and a hydraulic fluid for driving the hydraulic cylinder. A hydraulic pump / motor to be generated, a servo motor connected to the rotary shaft of the hydraulic pump / motor, a pressure detector for detecting the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder, and input A die cushion control method for controlling a die cushion device body having a drive unit for driving the servomotor based on a first torque command signal, wherein the die cushion simulator that models the die cushion device body is driven. Selecting a second driving mode to be performed; and when the second driving mode is selected, the die cushion pressure finger A die cushion pressure command signal indicating the die cushion pressure output from the vessel and a second die cushion pressure signal indicating the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder calculated in real time by the die cushion simulator And generating a second torque command signal that sets the pressure in the cushion pressure generation side pressurizing chamber of the hydraulic cylinder calculated by the die cushion simulator to a pressure corresponding to the die cushion pressure command signal. And outputting the generated second torque command signal to the die cushion simulator and when the second drive mode is selected, the die cushion simulator generates the generated second torque command signal. And slide position signal and slide indicating the position and speed of the slide of the press machine Output at least the second die cushion pressure signal in real time from physical quantities calculated in real time based on the degree signal, and at least the second die cushion pressure calculated by the die cushion simulator. A second die cushion pressure signal corresponding to the second die cushion pressure signal or the second die cushion force signal based on a signal or a second die cushion force signal calculated from the second die cushion pressure signal. Or displaying the second die cushion force on a display unit and / or recording the second die cushion force on the recording unit; and displaying the second die cushion pressure displayed on the display unit and / or recorded on the recording unit or A first drive for driving the die cushion device main body when the second die cushion force is within an allowable range. When the mode is selected and when the first drive mode is selected, the die cushion pressure command signal and the pressure in the pressure chamber on the cushion pressure generating side of the hydraulic cylinder detected by the pressure detector are indicated. The first pressure at the cushion pressure generation side pressurizing chamber of the hydraulic cylinder detected by the pressure detector based on the first die cushion pressure signal is set to a pressure corresponding to the die cushion pressure command signal. And generating the generated first torque command signal to the die cushion device main body.

  According to still another aspect of the present invention, first, a second drive mode for driving a die cushion simulator that models the die cushion apparatus main body is selected. When the second drive mode is selected, a second torque command signal for driving the die cushion simulator is generated, and the generated second torque command signal is output to the die cushion simulator. The die cushion simulator outputs at least the second die cushion pressure signal from physical quantities calculated in real time based on the generated second torque command signal and the like. A simulation result (second die cushion pressure or second die cushion force) by the die cushion simulator is displayed on the display unit and / or recorded on the recording unit. Then, when the simulation result is within an allowable range, a first drive mode for driving the die cushion device main body is selected. When the first drive mode is selected, a first torque command signal for driving the die cushion device main body is generated, and the generated first torque command signal is output to the die cushion device main body. As described above, since the die cushion pressure (force) is simulated in advance by the die cushion simulator, the operation can be adjusted safely and speedily.

  According to the present invention, since the die cushion simulator is provided and the adjustment of the die cushion control device can be confirmed by using the die cushion simulator instead of the actual die cushion device main body, the operation adjustment can be performed safely and speedily. Can do. Also, the die cushion pressure (force) can be accurately predicted using the die cushion simulator, and the die cushion pressure (force) generated for the set value related to the die cushion force by the man-machine controller It can be adjusted while checking without actually using a mold.

FIG. 1 is a configuration diagram showing a die cushion device main body and a press machine to which a die cushion control device according to the present invention is applied. FIG. 2 is a block diagram showing an embodiment of a die cushion control device according to the present invention. FIG. 3 is a block diagram showing a detailed configuration of the die cushion simulator shown in FIG. FIG. 4 is a waveform diagram showing changes in each physical quantity when the die cushion force is applied when the die cushion simulator is driven in the driving mode 2 (shows the result of the first step). FIG. 5 is a waveform diagram showing changes in physical quantities when the die cushion device is actuated when the die cushion device main body is driven under the same conditions as in the first step in the driving mode 1 (showing the result of the second step). FIG. 6 is a waveform diagram showing a die cushion force response waveform or the like when the die cushion simulator is driven with the surge suppression function enabled and the preliminary acceleration function disabled with respect to FIG. Show). FIG. 7 is a waveform diagram showing changes in each physical quantity when the die cushion device is actuated when the die cushion device main body is driven under the same conditions as in the third step (shows the result of the fourth step). FIG. 8 is a flowchart showing an embodiment of a die cushion control method according to the present invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a die cushion control device and a die cushion control method according to the present invention will be described in detail with reference to the accompanying drawings.

[Schematic configuration of press machine and die cushion device body]
FIG. 1 is a configuration diagram showing a die cushion device main body and a press machine to which a die cushion control device according to the present invention is applied.

  A press machine 10 shown in FIG. 1 includes a bed 11, a column 12, and a crown 13, and a slide 14 is guided by a guide portion 15 provided in the column 12 so as to be movable in the vertical direction. The slide 14 is moved up and down in FIG. 1 by a crank mechanism including a crankshaft 17 and a connecting rod 18 to which a rotational driving force is transmitted from the press driving device 16.

  The press drive device 16 includes a servo motor, a servo amplifier, an encoder (not shown), an encoder mounted on the crank shaft or the rotation shaft of the servo motor, and a speed reducer, and an angle command for the crank shaft output from the slide position command device of the press control device 19. Alternatively, the servomotor is driven based on the torque command signal calculated based on the servomotor angle command and the crankshaft angle or the servomotor angle, and as a result, the position (slide position) of the slide 14 is controlled. Further, the press control device 19 outputs a slide position command signal to the die cushion control device 200 (FIG. 2).

  An upper mold 20 is mounted on the slide 14, and a lower mold 22 is mounted on the bolster of the bed 11. Between the upper mold 20 and the lower mold 22, a blank holder (claw presser plate) 102 is disposed, the lower side is supported by a cushion pad 110 via a plurality of cushion pins 104, and the material 30 is set on the upper side. (Contact).

  The press machine 10 presses the material 30 between the upper mold 20 and the lower mold 22 by lowering the slide 14.

  Note that the molds (upper mold 20 and lower mold 22) in this example are used for molding a hollow cup-shaped (drawer-shaped) product closed on top. The crankshaft 17 is provided with a crankshaft encoder 24 for detecting the angular velocity and angle of the crankshaft 17 for controlling the die cushion. The crankshaft encoder 24 sends the crankshaft encoder signal to the die cushion control device. 200 (FIG. 2).

  The die cushion device includes a die cushion device main body 100 and a die cushion control device 200 (FIG. 2).

  The die cushion apparatus main body 100 mainly includes a blank holder 102, a cushion pad 110 that supports the blank holder 102 via a plurality of cushion pins 104, and a hydraulic cylinder that supports the cushion pad 110 and generates a die cushion force on the cushion pad 110. (Hydraulic cylinder) 120 and a hydraulic circuit 150 that drives the hydraulic cylinder 120.

  The hydraulic cylinder 120 and the hydraulic circuit 150 function as a cushion pad elevator that moves the cushion pad 110 up and down, and also functions as a die cushion force generator that causes the cushion pad 110 to generate a die cushion force.

  In addition, a die cushion position detector 124 that detects the position of the piston rod 120a of the hydraulic cylinder 120 in the expansion / contraction direction as the position of the cushion pad 110 in the up-and-down direction is provided for the hydraulic cylinder 120. Note that the die cushion position detector may be provided between the bed 11 and the cushion pad 110.

  Next, the configuration of the hydraulic circuit 150 that drives the hydraulic cylinder 120 will be described.

  The hydraulic circuit 150 includes an accumulator 152, a hydraulic pump / motor (hydraulic pump / motor) 154, a servo motor 156 connected to the rotary shaft of the hydraulic pump / motor 154, and an angular velocity of the drive shaft of the servo motor 156 (servo motor angular velocity ω). ), A relief valve 160, a check valve 162, and a pressure detector 164.

  The accumulator 152 is set with a low gas pressure, serves as a tank, and supplies substantially constant low-pressure oil to the cushion pressure generation side pressurizing chamber 120b of the hydraulic cylinder 120 via the check valve 162, thereby providing a die cushion. It also plays a role of making it easy to increase pressure during pressure control.

  One port (discharge port) of the hydraulic pump / motor 154 is connected to the cushion pressure generation side pressurizing chamber 120 b of the hydraulic cylinder 120, and the other port is connected to the accumulator 152.

  The relief valve 160 operates as a means for preventing damage to the hydraulic equipment by operating when abnormal pressure is generated (when the die cushion force control is impossible and sudden abnormal pressure is generated). Further, the lowering side pressurizing chamber (pad side pressurizing chamber) 120 c of the hydraulic cylinder 120 is connected to the accumulator 152.

  The pressure acting on the cushion pressure generation side pressurizing chamber 120b of the hydraulic cylinder 120 is detected by the pressure detector 164, and the angular velocity of the drive shaft of the servo motor 156 is detected by the angular velocity detector 158.

  In FIG. 1, reference numeral 170 denotes a servo amplifier including a PWM (Pulse Width Modulation) controller. The servo amplifier 170 receives a torque command signal (first torque command signal) input from a die cushion control device 200 described later. Based on the above, the drive power corresponding to the first torque command signal is output to the servo motor 156 and functions as a drive unit for driving the servo motor 156.

  The DC power source 172 with a power regenerator converts AC power from the AC power source 174 into DC and supplies it to the servo amplifier 170, but the slide 14 collides with the material 30 (and the blank holder 102) during die cushion force control. Then, at the time of descent from the bottom dead center (molding), the power (regenerative power) generated by the servo motor 156 acting as a generator is received via the servo amplifier 170 and is supplied to the AC power source 174. Return it.

  That is, at the time of die cushion force control, the torque output direction of the servo motor 156 is opposite to the generated speed, and pressure oil is received from the cushion pressure generating side pressure chamber 120b of the hydraulic cylinder 120 by the power received by the cushion pad 110 from the slide 14. It flows into the hydraulic pump / motor 154, and the hydraulic pump / motor 154 acts as a hydraulic motor. The servo motor 156 is driven by the hydraulic pump / motor 154 to act as a generator. The electric power generated by the servo motor 156 is returned (regenerated) to the AC power source 174 via the servo amplifier 170 and the DC power source 172 with a power regenerator.

[Principle of die cushion force control]
Since the die cushion force can be expressed by the product of the pressure in the cushion pressure generation side pressurizing chamber 120b of the hydraulic cylinder 120 and the cylinder area, controlling the die cushion force is the pressurization on the cushion pressure generation side of the hydraulic cylinder 120. This means that the pressure in the chamber 120b is controlled.

Now, hydraulic cylinder / cushion pressure generation side cross section: A
Hydraulic cylinder / cushion pressure generation side volume: V
Die cushion pressure: P
Electric (servo) motor torque: T
Inertia moment of servo motor: I
Servo motor viscous resistance coefficient: DM
Servo motor friction torque: fM
Hydraulic motor displacement: Q
Force applied to the hydraulic cylinder piston rod from the _slide : F _slide
Pad speed generated when pressed by the press: v
Inertial mass of hydraulic cylinder piston rod + pad: M
Viscous resistance coefficient of hydraulic cylinder: DS
Friction force of hydraulic cylinder: fS
Servo motor speed rotated by pressure oil: ω
Volumetric modulus of hydraulic oil: K
Proportional constant: k1, k2
Then, the static behavior can be expressed by equations (1) and (2).

P = ∫K ((v · A−k1Q · ω) / V) dt (1)
T = k2 · PQ / (2π) (2)
Further, dynamic behavior can be expressed by equations (3) and (4) in addition to equations (1) and (2).

PA-F _slide = M.dv / dt + DS.v + fS (3)
T−k2 · PQ / (2π) = I · dω / dt + DM · ω + fM (4)
What the above formulas (1) to (4) mean, that is, the force transmitted from the slide 14 to the hydraulic cylinder 120 via the cushion pad 110 compresses the cushion pressure generation side pressurizing chamber 120b of the hydraulic cylinder 120, Generate die cushion pressure. At the same time, the hydraulic pump / motor 154 acts as a hydraulic motor by the die cushion pressure. When the rotation shaft torque generated in the hydraulic pump / motor 154 resists the drive torque of the servo motor 156, the servo motor 156 is rotated to Rise is suppressed. Eventually, the die cushion pressure is determined according to the drive torque of the servo motor 156.

[Die cushion control device]
FIG. 2 is a block diagram showing an embodiment of a die cushion control apparatus 200 according to the present invention.

  The die cushion control device 200 controls the die cushion device main body 100 shown in FIG. 1, and includes a die cushion simulator 240 that models the die cushion device main body 100 and a press simulator 250 that models the press machine 10. And. Moreover, it is preferable that the die cushion control device 200 includes a conveyance simulator that models the conveyance device that carries the material 30 into the press machine 10 and carries out the press-molded product from the press machine 10.

  When using (driving) the die cushion simulator 240, simulation can be performed without driving the press machine 10 (actual machine) by using the press simulator 250, and the transport device is driven by using the transport simulator. The simulation can be performed without doing.

  The drive mode of the die cushion control device 200 includes the following drive modes.

(1) Drive mode 1 (die cushion: simulator, press: simulator, transport: simulator)
(2) Drive mode 2 (die cushion: simulator, press: actual machine, transport: actual machine)
(3) Drive mode 3 (die cushion: simulator, press: actual machine data, transport: actual machine data)
(4) Drive mode 4 (die cushion: actual machine, press: actual machine, transport: actual machine)
Note that the “actual machine data” in the drive mode 3 means that the press machine main body and the transport apparatus main body are not driven, but are measured in advance from the press machine main body and the transport apparatus main body and stored in the memory in the press simulator for use (simulation). ), A simulation method in which a slide position signal, a slide speed signal, a transport position signal, and the like are output from a memory in real time.

  The die cushion control device 200 shown in FIG. 2 uses a simulator as an alternative to the actual machine when performing line-linked adjustment of the press machine 10 and the die cushion device main body 100, or the press machine 10, the transport device, and the die cushion device main body 100. By using it, it is possible to adjust the driving safely and speedily. The die cushion control device 200 of this example is not provided with a transfer simulator, and the description of the transfer device is omitted in the following description.

  The die cushion control device 200 controls the die cushion device main body 100 shown in FIG. 1 and mainly includes a die cushion pressure controller 210, a die cushion position controller 220, a command selector 230, a die cushion simulator 240, a press. It comprises a simulator 250, a selector 260, selectors 262a, 262b, 262c that function as input / output selectors, selectors 264a, 264b, signal converters 270, 272, 274, 276, 278, and an output unit 280. .

  To the press simulator 250 of the die cushion control device 200, a slide position command signal can be input from the press control device 19 of the press machine 10 shown in FIG. Further, detection signals of the crankshaft encoder 24, the die cushion position detector 124, the pressure detector 164, and the angular velocity detector 158 can be input to the signal converters 270, 272, 274, and 276, respectively.

  On the other hand, the die cushion control device 200 transmits the torque command signal (first torque command signal) generated by the die cushion pressure controller 210 or the die cushion position controller 220 via the command selector 230 and the selector 260. Output to the cushion device main body 100 (servo amplifier 170) is possible.

  Moreover, the die cushion control apparatus 200 of this example includes a drive mode selector (not shown) that selects any one of the four drive modes 1 to 4 described above.

  When drive mode 1 is selected by the drive mode selector, the selector 260, selectors 262a, 262b, 262c, and selectors 264a, 264b are all switched to the input terminal a side.

  The selector 254 outputs the slide position command calculated by the slide position command unit 252 when switched to a1, and the slide position command output from the press control device 19 when switched to a2, to the press real time calculator. In contrast to the basic form when a1 is selected to complete the press simulator 250 in the die cushion controller, when a2 is selected, the slide position signal and slide speed signal can be approximated to the characteristics of the actual machine. it can.

Further, since the operation of the press control device 19 for controlling the press machine 10 is accompanied, a more realistic simulation is possible. In the third step, which will be described later, which is advantageous to the user, the press machine is driven using an actual machine. In contrast to mode 2, it is effective when the press machine 10 is also replaced with drive mode 1 using a simulator. (It is convenient to adjust the die cushion force in the third step safely without driving the press machine or the die cushion device.)
When the driving mode 2 is selected by the driving mode selector, the selector 260 and the selectors 262a, 262b, 262c are switched to the input terminal a side, and the selectors 264a, 264b are respectively switched to the input terminal b side. It is done.

  When the driving mode 3 is selected by the driving mode selector, the selector 260 and the selectors 262a, 262b, 262c, 264a, 264b are switched to the input terminal a side.

  The slide position signal and slide speed signal are output in real time from the memory in the press real time calculator of the press simulator 250 by switching a selector (not shown).

  When the drive mode 4 is selected by the drive mode selector, the selector 260, the selectors 262a, 262b, 262c, and the selectors 264a, 264b are respectively switched to the input terminal b side.

  FIG. 2 shows the case where the drive mode 1 is selected. In addition, without providing the drive mode selector, the operator may appropriately switch the selector 254, selector 260, selectors 262a, 262b, 262c, and selectors 264a, 264b according to the drive mode. In this case, the selector 254, the selector 260, the selectors 262a, 262b, 262c, and the selectors 264a, 264b function as drive mode selectors.

  However, the selector 260 and the selectors 262a, 262b, and 262c must align the input terminals of the drive mode selector with a or b. That is, it is necessary to unify whether to drive the die cushion simulator 240 or to drive the die cushion device main body 100.

  The press simulator 250 is a model of the press machine 10 shown in FIG. 1, and particularly when the press machine 10 is not driven, a slide position signal and a slide speed signal indicating the position and speed of the slide 14 of the press machine 10 are provided. Each is calculated in real time.

  The press simulator 250 includes a slide position command unit 252, a selector 254 that functions as an input / output selector, and a press real-time calculator 256.

  The slide position command signal from the slide position command device 252 is applied to one input terminal a1 of the selector 254, and the slide position command signal from the press control device 19 of the press machine 10 is applied to the other input terminal a2 of the selector 254. The signal is added, and the selector 254 outputs one of the two slide position command signals to the press real time calculator 256. When the input terminal a2 is selected, it is possible to perform a more realistic simulation with the press machine 10 in front of the user. In particular, it is possible for the user to determine the validity of operations and settings performed on the servo die cushion device. This is effective when performing a simulation to be confirmed in advance.

  The press real time computing unit 256 generates a slide position signal and a slide speed signal indicating the position and speed of the slide 14 of the press machine 10 based on the slide position command signal input via the selector 254 in real time. The calculated slide position signal and slide speed signal are output to one input terminal a of the selectors 264a and 264b, respectively.

  Further, the memory in the press real time calculator 256 stores slide position data, slide speed data, and transport position data measured in advance from the press machine main body and the transport apparatus main body, and the drive mode 3 is selected. Sometimes, a slide position signal, a slide speed signal, and a transport position signal are output in real time.

  A crankshaft encoder signal is applied to the signal converter 270 from the crankshaft encoder 24 (FIG. 1) of the press machine 10, and the signal converter 270 receives a crankshaft angle signal from the input crankshaft encoder signal. The crank angular velocity signal is generated (converted) and output to the signal converter 278. The signal converter 278 converts the crankshaft angle signal and the crank angular speed signal input from the signal converter 278 into a slide position signal and a slide speed signal, and the converted slide position signal and slide speed signal are selected by the selectors 264a and 264b. To the other input terminal b. In this example, the crankshaft encoder 24 (FIG. 1) and the signal converters 270 and 278 function as a slide position detector and a slide speed detector. 14 may be provided with a slide position detector and a slide speed detector for detecting the position and speed of the slide 14.

  The selectors 264a and 264b selectively output the slide position signal and slide speed signal of the actual machine or the slide position signal and slide speed signal calculated by the press simulator 250 according to the drive mode.

  The die cushion simulator 240, which will be described in detail later, indicates a die cushion position signal (second die cushion position signal) indicating the position of the cushion pad 110, and the pressure of the cushion pressure generation side pressurizing chamber 120 b of the hydraulic cylinder 120. A die cushion pressure signal (second die cushion pressure signal) and an angular velocity signal (second angular velocity signal) indicating the angular velocity of the servo motor 156 are respectively calculated, and the calculated second die cushion position signal and second die cushion are calculated. The cushion pressure signal and the second angular velocity signal are output to one input terminal a of the selectors 262a, 262b, and 262c, respectively.

  The signal converters 272, 274 and 276 are supplied with detection signals from the die cushion position detector 124, the pressure detector 164 and the angular velocity detector 158, respectively. Respectively, a detection signal to be input is a die cushion position signal (first die cushion position signal) indicating the position of the cushion pad 110, and a die cushion pressure signal (a first cushion cushion signal) indicating the pressure of the cushion pressure generation side pressurizing chamber 120b of the hydraulic cylinder 120. The first die cushion pressure signal), and the angular velocity signal (first angular velocity signal) indicating the angular velocity of the servo motor 156, and the converted first die cushion position signal, first die cushion pressure signal, and second 1 angular velocity signal is output to the other input terminal b of the selectors 262a, 262b, 262c.

  The selectors 262a, 262b, 262c are the first die cushion position signal, the first die cushion pressure signal, and the first angular velocity signal of the actual machine, or the second calculated by the die cushion simulator 240 according to the driving mode. The die cushion position signal, the second die cushion pressure signal, and the second angular velocity signal are selectively output.

  The die cushion pressure controller 210 includes a die cushion pressure commander 212. Since the product of the pressure of the cushion pressure generation side pressurizing chamber 120b of the hydraulic cylinder 120 and the cylinder area is a die cushion force, controlling the pressure of the cushion pressure generation side pressurizing chamber 120b of the hydraulic cylinder 120 is not possible with the die cushion. Will control the force. Accordingly, the die cushion pressure controller 210 can include a die cushion force controller, and the die cushion pressure commander 212 can include a die cushion force commander.

  A slide position signal is applied to the die cushion pressure command device 212 in order to output a die cushion pressure command signal corresponding to the position of the slide 14.

  In the case of this example, the die cushion pressure command device 212 outputs, for example, a step-shaped die cushion pressure command signal, and controls the output timing of the die cushion pressure command signal based on the slide position signal.

  The die cushion pressure controller 210 controls the first die cushion pressure signal or the second die cushion pressure signal in order to control the die cushion pressure in accordance with the die cushion pressure command signal applied from the die cushion pressure commander 212. A torque command signal (first torque command signal or second torque command signal) is generated as a feedback signal. Further, the die cushion pressure controller 210 uses a servo motor angular velocity signal (first angular velocity signal or second angular velocity signal) as an angular velocity feedback signal for ensuring dynamic stability of the die cushion pressure.

  When the die cushion pressure controller 210 is switched from the die cushion position control state (die cushion standby position (holding) control state) to the die cushion pressure control state, the die cushion pressure command signal, the die cushion pressure signal (first Torque command signal (first torque command) based on the servomotor angular velocity signal (first angular velocity signal or second angular velocity signal) and slide velocity signal. Signal or second torque command signal). Here, the first torque command signal is a torque command signal generated using the first die cushion pressure signal and the first angular velocity signal of the actual machine, and the second torque command signal is a die cushion simulator. 2 is a torque command signal generated using the second die cushion pressure signal and the second angular velocity signal calculated by 240.

  Further, the die cushion pressure controller 210 has a surge suppression function (a function for adjusting the operation degree of the control compensation for suppressing the surge and stabilizing the control by the user setting), and the operation degree of the control compensation by the surge suppression function. It is possible to generate a torque command signal reflecting the above.

  The die cushion position controller 220 includes a die cushion position commander 222.

  The die cushion position commander 222 is added with a die cushion position signal (first die cushion position signal or second die cushion position signal) for use in generating an initial value in position command generation. The cushion position commander 222 performs a product knockout operation after the slide 14 reaches the bottom dead center and ends the die cushion pressure control, and also makes the cushion pad 110 stand by at the die cushion standby position which is the initial position. In order to perform preliminary acceleration downward immediately before the start of the die cushion pressure control, a die cushion position command signal for controlling the die cushion position (the position of the cushion pad 110) is output.

  The die cushion position controller 220 controls the die cushion position signal (the first die cushion pressure signal or the second die cushion pressure signal) in accordance with the die cushion position command signal applied from the die cushion position commander 222. The torque command signal (first torque command signal or second torque command signal) is generated using the cushion position signal) as a position feedback signal. The die cushion position controller 220 uses a servo motor angular velocity signal (first angular velocity signal or second angular velocity signal) as an angular velocity feedback signal for ensuring dynamic stability of the position of the cushion pad 110. .

  In the die cushion position control state, the die cushion position controller 220 outputs a die cushion position command signal, a die cushion position signal (first die cushion position signal or second die cushion) output from the die cushion position commander 222. A torque command signal (first torque command signal or second torque command signal) is generated based on the position signal) and the servo motor angular velocity signal (first angular velocity signal or second angular velocity signal). Here, the first torque command signal is a torque command signal generated using the first die cushion position signal and the first angular velocity signal of the actual machine, and the second torque command signal is a die cushion simulator. This is a torque command signal generated using the second die cushion position signal and the second angular velocity signal calculated by 240.

  Further, the die cushion control device 200 has a preliminary acceleration function (a function of preliminarily accelerating the cushion pad 110 immediately before impact, reducing impact caused by impact, and suppressing overshoot and undershoot of the die cushion pressure). The die cushion position commander 222 of the cushion position controller 220 outputs a die cushion position command signal according to whether or not the preliminary acceleration function is used according to user settings. When using the pre-acceleration function, the die cushion position commander 222 determines the slide speed and slide position signal at the time of impact (the slide reaches the die cushion force control start position (die cushion standby position in the slide position coordinates)). A pre-acceleration die cushion position command signal calculated based on a strength setting value indicating the degree of pre-acceleration is output.

  The command selector 230 includes a torque command signal (first torque command signal or second torque command signal) generated by the die cushion pressure controller 210 or a torque command signal generated by the die cushion position controller 220. (The first torque command signal or the second torque command signal) is added, and the command selector 230 determines that the slide 14 has a die cushion force control step, mainly a molding step, based on the slide position signal and the die cushion position signal. Or the die cushion position control process, mainly in the non-molding process area, and if the slide 14 is in the molding process area, it is generated by the die cushion pressure controller 210. A torque command signal (a first torque command signal or a second torque command signal) is selectively output, and the slide 14 is brought into the non-molding process region. If that selectively outputs a torque command signal generated by the die cushion position controller 220 (first torque command signal or the second torque command signal).

  The selector 260 switches the torque command signal (first torque command signal or second torque command signal) selected by the command selector 230 to the die cushion simulator 240 or the die cushion device main body 100 according to the drive mode. Output. That is, in the driving mode 4 (first driving mode) for driving the die cushion device main body 100 (actual machine), the input torque command signal (first torque command signal) is output to the die cushion device main body 100. In the driving modes 1 to 3 (second driving mode) in which the die cushion simulator 240 is used (driven), the input torque command signal (second torque command signal) is output to the die cushion simulator 240.

<Outline of Die Cushion Simulator 240>
The die cushion simulator 240 includes discrete elements including linear elements and nonlinear elements based on the equations of motion and mechanical characteristics of each part, including from the torque command signal to the cushion pad position signal, within the NC (Numerical Control) of the die cushion control apparatus 200. In the time system, it is configured to be physically equivalent to the die cushion device itself, and multiple physical quantities derived from the torque command signal to the cushion pad position signal are calculated in real time (in real time) (digitally). The second die cushion position signal indicating the position of the cushion pad 110, the second die cushion pressure signal indicating the pressure in the cushion pressure generating side pressurizing chamber 120b of the hydraulic cylinder 120, and the second speed indicating the angular velocity of the servo motor 156. 2 angular velocity signal is output.

  The model configuration range of the die cushion simulator 240 mainly includes the second torque command signal, the input portion of the slide position signal and the slide speed signal, the servo amplifier 170 of the servo motor 156, the servo motor 156, the angular velocity detector 158, the hydraulic pump / The motor 154, the hydraulic piping section, and the hydraulic cylinder 120 are covered, and the output section of the second die cushion position signal, the second die cushion pressure signal, and the second angular velocity signal is covered.

  The die cushion simulator 240 includes a die cushion real time calculator 242. A torque command signal (second torque command signal) is applied to the die cushion real-time calculator 242 via a selector 260, and a slide position signal and a slide speed signal are applied via selectors 264a and 264b. Based on these input signals, the die cushion real time calculator 242 is a second die cushion position signal that indicates at least the position of the cushion pad 110 in real time, and a cushion pressure generation side pressurizing chamber of the hydraulic cylinder 120. The second die cushion pressure signal indicating the pressure of 120b and the second angular velocity signal indicating the angular velocity of the servo motor 156 are digitally calculated, and the calculated second die cushion position signal, second die cushion pressure signal, And the second angular velocity signal are input to one of the selectors 262a, 262b, 262c, respectively. And outputs it to the child a.

  FIG. 3 is a block diagram showing a detailed configuration of the die cushion simulator 240 shown in FIG.

  As shown in FIG. 3, the die cushion simulator 240 covers each element of a servo amplifier, a servo motor, an angular velocity detector, a hydraulic pump / motor, a hydraulic piping unit, a hydraulic cylinder, and a cushion pad. Further, the elements in the block diagram of FIG. 2 are nonlinear elements such as the resolution and frictional force of the PWM controller included in the servo amplifier and the angular velocity detector (Encoder) of the servomotor.

  Moreover, each symbol in FIG. 3 is as follows.

X _S : Slide position (mm)
V _S : Slide speed (mm / s)
ω _M : Servo motor angular velocity (rad / s)
T _r : Servo motor torque command (kgm)
S: Laplace operator ω ₁ : Angular frequency of the first-order lag system [rad / s]
R: Internal resistance of servo motor (Ω)
L: Inductance of the servo motor coil (H)
K _T : Servo motor torque constant (kgm / A)
Ke: Back electromotive force constant of servo motor (Vs / rad)
g: Gravity acceleration 9.806 (m / s ² )
J _M : Total moment of inertia of servo motor and hydraulic pump / motor (kgm ² )
D _M : Total viscous resistance of servo motor and hydraulic pump / motor (kgms / rad)
q: Hydraulic pump / motor displacement (m ³ / s)
K: Volumetric modulus of hydraulic oil (kg / m ² )
A: Cross section of hydraulic cylinder (m ² )
V _O : Hydraulic cylinder and pipe volume (m ³ )
M: Mass connected to the cushion pad (kg)
f: Friction force (kg)
D _C : Viscosity resistance (kgm / s)
X: Die cushion position (mm)
P: Die cushion pressure (kg / m ² )
As shown in FIG. 3, the die cushion simulator 240 receives the servo motor torque command T _r , the slide position X _S , and the slide speed V _S , and the die cushion pressure P.P. The die cushion position X and the servo motor angular velocity ω _M are calculated and output.

  Returning to FIG. 2, the output unit 280 outputs the die cushion position signal (first die cushion position signal or second die cushion position signal) and the die cushion pressure signal (via the selector 262a and the selector 262b). A first die cushion pressure signal or a second die cushion pressure signal), a slide position signal, an elapsed time, and the like. The output unit 280 displays the die cushion pressure (or die cushion force) corresponding to the slide position on the display unit based on the slide position, and / or records it on the recording unit, and also uses the elapsed time as a reference. The die cushion pressure (die cushion force) corresponding to the elapsed time is displayed on the display unit and / or recorded on the recording unit.

  Accordingly, the simulation result by the die cushion simulator 240 is displayed on the display unit and / or recorded in the recording unit, thereby confirming the simulation result, while debugging the control algorithm, eliminating human error, and die cushion force. Relevant set values can be corrected, and the operation results when the actual die cushion device main body 100 is driven are displayed on the display unit and / or recorded in the recording unit, thereby confirming the operation results. However, it is possible to correct the setting value related to the die cushion force.

[Action]
Next, the operation of the die cushion control device 200 will be described by comparing the drive mode 2 and the drive mode 4. The drive mode 2 is a drive mode (second drive) in which the die cushion simulator 240 is driven without using (driving) the die cushion apparatus main body 100 (actual machine) and the press machine 10 (actual machine) is driven. The drive mode 4 is a drive mode (first drive mode) when driving the die cushion apparatus main body 100 (actual machine) and the press machine 10 (actual machine).

<First step>
First, the driving mode 2 is selected, the press machine 10 (actual machine) is driven, and the die cushion simulator 240 is interlocked. The die cushion process speed (molding speed), which is the main condition during operation, is 447.5 mm / s, the preliminary acceleration level for the preliminary acceleration function is set to “standard”, and the surge suppression function is set to “unused”. did.

  The die cushion simulator 240 inputs the second torque command signal generated by the die cushion pressure controller 210 when the slide 14 is in the area of the die cushion force control process, mainly the molding process, When the control process, mainly the slide 14 is in the non-molding process area, the second torque command signal generated by the die cushion position controller 220 is input, and the crankshaft encoder is driven by the press machine 10. The slide position signal and slide speed signal converted from the crankshaft encoder signal output from 24 are input. The die cushion simulator 240 digitally outputs a second die cushion position signal, a second die cushion pressure signal, and a second angular velocity signal in real time from a plurality of physical quantities calculated based on these input signals. Output.

  The calculation result (simulation result) by the die cushion simulator 240 is used to generate the second torque command signal in the die cushion pressure controller 210 and the die cushion position controller 220, and can be confirmed by the output unit 280. .

  4 is a waveform diagram showing changes in physical quantities when the die cushion force is applied in the driving mode 2. FIG. 4A is a waveform diagram showing a slide position and a die cushion position (DC position). (B) is a waveform diagram showing a die cushion pressure (force) command (DC load command) and a die cushion force response (DC load), and FIG. 4 (C) shows a slide speed and a cushion pad speed (pad speed). FIG.

  According to the simulation result shown in FIG. 4, the die cushion force waveform is unstable. However, considering that the slide speed is relatively fast, the surge suppression function is not used, and as a result, the die cushion force peak value is within an allowable range on the device strength, the die cushion control device 200 (die cushion) It can be determined that the pressure (force) control algorithm) is operating normally (no bugs are generated).

  The process up to this confirmation is the most tense as a manufacturer. In this process, if the input / output signal is incorrect, the controller or control program (software) contains one minute problem, or a slight human error occurs, the die cushion device body If 100 (actual machine) is linked, not only will it not function properly, but it may break the machine and mold before completion. Since the die cushion simulator 240 that does not break is linked, it is safe (you can check the operation as many times as you like). This first step is the same as the case of using the actual machine except that the die cushion device main body 100 (actual machine) and the die cushion simulator 240 which are substantially equivalent to each other are exchanged. The parts up to the details of input / output signals between the die cushion control devices 200 and the error processing that occurs are the same as in the actual machine.

  Therefore, if this first step is completed with certainty, the basic interlocking function is completed with confirmation of the actual machine. Thereby, the die cushion control apparatus 200 (die cushion interlocking function) can be completed safely and quickly.

<Second step>
After confirming the basic die cushion interlocking function in the first step, the manufacturer takes the opportunity to switch from the driving mode 2 to the driving mode 4 to drive the die cushion device main body 100 (actual machine).

  In the drive mode 4, when the slide 14 is in the molding process region, the die cushion control device 200 outputs the first torque command signal generated by the die cushion pressure controller 210 to the servo amplifier of the die cushion device main body 100. When the slide 14 is in the non-molding process region, the first torque command signal generated by the die cushion position controller 220 is output to the servo amplifier 170 of the die cushion apparatus main body 100 to obtain the die cushion. The apparatus main body 100 (actual machine) is driven.

  FIG. 5 is a waveform diagram showing changes in physical quantities when the die cushion device main body 100 is driven under the same conditions as in the first step, and FIG. 5A shows the slide position and the DC position. FIG. 5B is a waveform diagram showing a DC load command and a DC load, and FIG. 5C is a waveform diagram showing a slide speed and a pad speed.

  Although the waveform diagram shown in FIG. 4 and the waveform diagram shown in FIG. 5 do not match, the trends are very similar. The die cushion function can be confirmed and the die cushion device can be completed without causing a single mistake (tapping mistake). This is a great advantage for manufacturers.

<Third step>
It has been found that the first step and the second step show substantially the same result (response tendency) when the die cushion simulator 240 is driven and when the die cushion device main body 100 (actual machine) is driven. The die cushion pressure (force) can be adjusted using the die cushion simulator 240 without using an actual machine. This step is particularly effective for users who perform molding using the apparatus.

  That is, FIG. 4 (and FIG. 5) shows a tendency that the die cushion force is unstable (large overshoot), and a more stable (small fluctuation) die cushion force action form is desired for molding. This adjustment from the unstable state to the stable state can be performed safely and promptly by using the die cushion simulator 240 rather than trying by using the actual mold. .

  6 is similar to FIG. 4 (using the die cushion simulator 240 as in FIG. 4 and the basic settings such as the die cushion force, the die cushion stroke, and the slide speed of the press machine 10 are the same). The die cushion force response waveform when the surge suppression function is enabled and the pre-acceleration function (function to lower before impact) is disabled is shown in order to further stabilize the process and speed up the rising response.

  As shown in FIG. 6B, the die cushion force acts stably and with a high response. The user can adjust the die cushion force safely and quickly using the die cushion simulator 240 until the third step.

<4th step>
After the adjustment of the die cushion force in the third step, the user has to switch from drive mode 2 to drive mode 4 to drive the die cushion device main body 100 (actual machine) and press mold the material using a mold. To do. Trial and error are not required, and the die cushion force can be applied as intended with stable and high response from the first molding.

  FIG. 7 is a waveform diagram showing changes in each physical quantity when the die cushion force is applied when the die cushion apparatus main body 100 is driven under the same conditions as in the third step.

  Although the waveform diagram shown in FIG. 6 and the waveform diagram shown in FIG. 7 do not match, the trends are very similar. The actual machine can be driven without making a single mistake. This is a great advantage for the user.

[Die cushion control method]
FIG. 8 is a flowchart showing an embodiment of a die cushion control method according to the present invention. In particular, the die cushion control device 200 shown in FIG. 2 is used to control the die cushion device main body 100 and start manufacturing the product. Shown for control.

  In FIG. 8, first, the second drive mode that is one of the drive modes 1 to 3 for driving the die cushion simulator 240 is selected (step S10).

  When the second drive mode is selected, the die cushion simulator 240 is driven to perform a cycle operation (step S12). In this case, the die cushion pressure controller 210 is also cycled.

  That is, the die cushion pressure controller 210 generates and generates a second torque command signal based on the die cushion pressure command signal and the second die cushion pressure signal calculated in real time by the die cushion simulator 240. The second torque command signal is output to the die cushion simulator 240. Further, the die cushion simulator 240 is based on at least a second torque command signal generated by the die cushion pressure controller 210 and a slide position signal and a slide speed signal indicating the slide position and speed of the press machine. Calculate and output the die cushion pressure signal in real time.

  Subsequently, based on the second die cushion pressure signal calculated from the second die cushion pressure signal or the second die cushion pressure signal calculated by the die cushion simulator 240, the second die cushion pressure signal or the second die cushion pressure signal is calculated. The second die cushion pressure or the second die cushion force corresponding to the die cushion force signal is displayed on the display unit and / or recorded on the recording unit (step S14).

  Next, based on the simulation result (die cushion pressure (force)) displayed on the display unit or the like, it is determined whether or not the die cushion pressure (force) is within the allowable range for molding using the mold (step) S16). In step S16, an error such as no die cushion force can be confirmed.

  When the die cushion pressure (force) is not within the allowable range (in the case of “No”), the operation adjustment including setting of the preliminary acceleration level in the preliminary acceleration function, setting of the surge suppression level in the surge suppression function, etc. is performed. This is performed (step S18). Also, if an error occurs, take measures to eliminate it. On the other hand, when the die cushion pressure (force) is at least within the allowable range for molding (in the case of “Yes”), the process proceeds to step S20.

  In step S20, instead of the second drive mode, the first drive mode, which is the drive mode 4 for driving the die cushion device main body 100 (actual machine), is selected.

  When the first drive mode is selected, the die cushion apparatus main body 100 (actual machine) is driven, and the die cushion apparatus main body 100 (actual machine) and the die cushion pressure controller 210 are cycled (step S22). In step S22, the press machine 10 press-molds the material using a mold ("test hitting" is performed).

  It is determined whether or not the product press-molded by trial strike is a non-defective product (step S24). If the press-molded product is not good (if there are cracks or wrinkles) (if “No”), “Shim adjustment” to adjust the die cushion force for each part of the product, or the actual die cushion pressure While confirming the waveform of (force), operation adjustment is performed including the setting of the die cushion pressure, the voltage setting, the setting of the pre-acceleration level in the pre-acceleration function, the setting of the surge suppression level in the surge suppression function (step S26). .

  On the other hand, when it is determined that the product press-molded by the trial strike is a non-defective product (in the case of “Yes”), this processing is terminated.

[Others]
The die cushion control device of the present embodiment performs die cushion pressure (force) control for controlling the die cushion force generated by the hydraulic cylinder of the die cushion device body and die cushion position control for controlling the position of the cushion pad. The present invention can also be applied to a die cushion control device that performs only die cushion pressure (force) control. In this case, the die cushion simulator only needs to simulate the die cushion pressure (force).

  In addition, the die cushion control device of the present embodiment ensures the dynamic stability of the die cushion pressure during die cushion pressure control by using an angular velocity signal (first angular velocity signal or second angular velocity signal) indicating the angular velocity of the servomotor. Used as an angular velocity feedback signal, and used as an angular velocity feedback signal to ensure the dynamic stability of the cushion pad position during die cushion position control. The die cushion simulator may not output an angular velocity signal (second angular velocity signal).

  Moreover, although this embodiment demonstrated the case where oil was used as a hydraulic fluid of a die-cushion apparatus main body, you may use not only this but water and another liquid. That is, in the present embodiment, the description has been made in the form using the hydraulic cylinder and the hydraulic circuit, but the present invention is not limited to these, and the hydraulic cylinder and hydraulic circuit using water and other liquids are used in the present invention. It goes without saying that it can be used.

  Furthermore, the present invention is not limited to the above examples, and it goes without saying that various improvements and modifications may be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Press machine 11 Bed 12 Column 13 Crown 14 Slide 15 Guide part 16 Press drive device 17 Crankshaft 18 Connecting rod 19 Press control device 20 Upper mold 22 Lower mold 24 Crankshaft encoder 30 Material 100 Die cushion apparatus main body 102 Blank holder 104 Cushion pin 110 Cushion pad 120 Hydraulic cylinder 120a Piston rod 120b Cushion pressure generation side pressurizing chamber 124 Die cushion position detector 150 Hydraulic circuit 152 Accumulator 154 Hydraulic pump / motor 156 Servo motor 158 Angular speed detector 160 Relief valve 162 Check valve 164 Pressure detection 170 Servo amplifier 172 DC power supply 174 with power regenerator AC power supply 200 Die cushion controller 210 Die cushion pressure controller 212 Dyke Pressure commander 220 Die cushion position controller 222 Die cushion position commander 230 Command selector 240 Die cushion simulator 242 Die cushion real time calculator 250 Press simulator 252 Slide position commanders 254, 260, 262a, 262b, 262c, 264a 264b selector 256 press real time calculator 270, 272, 274, 276, 278 signal converter 280 output unit

Claims (15)

A cushion pad; a hydraulic cylinder that supports the cushion pad and generates a die cushion force when the slide of the press machine is lowered; and a hydraulic pump / motor that generates hydraulic fluid for driving the hydraulic cylinder; Based on a servo motor connected to the rotary shaft of the hydraulic pump / motor, a pressure detector for detecting the pressure of the cushion pressure generating side pressurizing chamber of the hydraulic cylinder, and an input first torque command signal A die cushion control device for controlling a die cushion device main body having a drive unit for driving the servo motor,
A die cushion pressure commander that outputs a die cushion pressure command signal indicating a preset die cushion pressure;
A drive mode selector for selecting a first drive mode for driving the die cushion device body, or a second drive mode for driving a die cushion simulator that models the die cushion device body;
When the first drive mode is selected by the drive mode selector, the pressure is determined based on the die cushion pressure command signal and the first die cushion pressure signal indicating the pressure detected by the pressure detector. The first torque command signal is generated by setting the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder detected by the detector to a pressure corresponding to the die cushion pressure command signal. When the second drive mode is selected by the drive mode selector, the hydraulic pressure calculated by the die cushion pressure command signal and the die cushion simulator is output. Based on the second die cushion pressure signal indicating the pressure in the pressure chamber on the cylinder cushion pressure generation side, the die cushion A second torque command signal is generated to set the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder calculated by the emulator to a pressure corresponding to the die cushion pressure command signal, and the generated second torque A die cushion pressure controller that outputs a command signal to the die cushion simulator;
The die cushion simulator that outputs at least the second die cushion pressure signal from among physical quantities calculated based on at least the second torque command signal and a slide position signal indicating a slide position of the press machine;
When the first drive mode is selected by the drive mode selector, the first die cushion pressure signal detected by the pressure detector is input to the die cushion pressure controller, and the first When the torque command signal is output to the die cushion device main body and the second drive mode is selected by the drive mode selector, the second die cushion pressure signal calculated by the die cushion simulator is output to the die cushion device. An input / output selector that inputs to the cushion pressure controller and outputs the second torque command signal to the die cushion simulator;
A die cushion control device.   When the second drive mode is selected by the drive mode selector, a second value calculated from at least the second die cushion pressure signal or the second die cushion pressure signal calculated by the die cushion simulator. Based on the die cushion force signal, the second die cushion pressure signal or the second die cushion pressure signal corresponding to the second die cushion force signal or the second die cushion force signal is displayed on the display, and / or Or the die cushion control apparatus of Claim 1 provided with the output part recorded on a recording part.   The output unit is calculated from at least the first die cushion pressure signal or the first die cushion pressure signal detected by the pressure detector when the first driving mode is selected by the driving mode selector. Based on the first die cushion force signal, the first die cushion pressure signal or the first die cushion pressure signal corresponding to the first die cushion pressure signal is displayed on the display. The die cushion control device according to claim 2, wherein the die cushion is recorded on the recording unit. The die cushion device main body has an angular velocity detector for detecting the angular velocity of the servo motor,
When the first drive mode is selected by the drive mode selector, the die cushion pressure controller includes a first die cushion pressure indicating a pressure detected by the die cushion pressure command signal and the pressure detector. Based on the signal and the first angular velocity signal indicating the angular velocity of the servo motor detected by the angular velocity detector, the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder detected by the pressure detector is determined. , Generating the first torque command signal to a pressure corresponding to the die cushion pressure command signal, outputting the generated first torque command signal to the die cushion device main body, and by the drive mode selector When the second drive mode is selected, the value calculated by the die cushion pressure command signal and the die cushion simulator Based on a second die cushion pressure signal indicating the pressure of the pressure cylinder on the cushion pressure generation side of the hydraulic cylinder and a second angular velocity signal indicating the angular velocity of the servomotor calculated by the die cushion simulator, the die A second torque command signal is generated to set the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder calculated by a cushion simulator to a pressure corresponding to the die cushion pressure command signal, and the generated second torque command signal is generated. Output torque command signal to the die cushion simulator,
The die cushion simulator includes at least the second die cushion pressure signal and the first quantity among physical quantities calculated based on at least the second torque command signal and a slide position signal indicating a slide position of the press machine. 2 angular velocity signals are output,
The input / output selector is detected by the first die cushion pressure signal detected by the pressure detector and the angular velocity detector when the first driving mode is selected by the driving mode selector. The first angular velocity signal is input to the die cushion pressure controller, and the first torque command signal is output to the die cushion apparatus body, and the second driving mode is selected by the driving mode selector. Then, the second die cushion pressure signal and the second angular velocity signal calculated by the die cushion simulator are input to the die cushion pressure controller, and the second torque command signal is input to the die cushion simulator. The die cushion control device according to any one of claims 1 to 3, wherein the die cushion control device is configured to output to the die cushion.   The die cushion control apparatus according to claim 4, wherein the die cushion simulator digitally calculates the second die cushion pressure signal and the second angular velocity signal.   The die cushion control apparatus according to claim 4, wherein the die cushion simulator calculates the second die cushion pressure signal and the second angular velocity signal in real time.   The die cushion control device according to any one of claims 4 to 6, wherein the die cushion simulator includes linear elements and nonlinear elements that are physically equivalent to the die cushion apparatus main body.   The die cushion pressure controller uses the first die cushion pressure signal detected by the pressure detector as a pressure feedback signal when the first drive mode is selected by the drive mode selector. And using the first angular velocity signal detected by the angular velocity detector as an angular velocity feedback signal for ensuring dynamic stability of the pressure in the cushion pressure generating side pressurizing chamber of the hydraulic cylinder, When the second driving mode is selected by the selector, the second die cushion pressure signal calculated by the die cushion simulator is used as a pressure feedback signal, and the second cushion mode calculated by the die cushion simulator is used. Before the angular velocity signal of 2 is calculated by the die cushion simulator Die cushion control apparatus according to any one of claims 4 to be used as an angular velocity feedback signal for ensuring the dynamic stability of the pressure cushion pressure generation side pressure chamber of the hydraulic cylinder 7. A press simulator that models the press machine, which calculates a slide position signal and a slide speed signal respectively indicating a slide position and a speed of the press machine based on a slide position command signal input from a slide position commander Equipped with a press simulator,
The input / output selector causes the die cushion simulator to input the slide position signal and the slide speed signal calculated by the press simulator when the second drive mode is selected by the drive mode selector. Item 9. The die cushion control device according to any one of Items 1 to 8.   The die cushion pressure controller further receives a slide position signal and a slide speed signal indicating the slide position and speed of the press machine, and inputs the slide position signal and slide speed signal to the first torque command signal and The die cushion control device according to claim 1, wherein the die cushion control device is used to generate the second torque command signal. A press simulator that models the press machine, which calculates a slide position signal and a slide speed signal respectively indicating a slide position and a speed of the press machine based on a slide position command signal input from a slide position commander Equipped with a press simulator,
When the first drive mode is selected by the drive mode selector, the input / output selector is detected by a slide position detector and a slide speed detector that detect the slide position and speed of the press machine, respectively. When the slide position signal and the slide speed signal are input to the die cushion pressure controller and the second drive mode is selected by the drive mode selector, the slide position signal calculated by the press simulator The die cushion control device according to claim 10, wherein the slide speed signal is input to the die cushion pressure controller. A die cushion position command device that outputs a die cushion position command signal indicating the position of the cushion pad;
A die cushion position detector for detecting the position of the cushion pad;
When the first drive mode is selected by the drive mode selector, the die cushion position command signal and the die cushion position detector detected when the slide is in a non-molding process region. Based on the first die cushion position signal indicating the position of the cushion pad, the position of the cushion pad detected by the die cushion position detector is set to a position corresponding to the die cushion position command signal. A torque command signal is generated, and the generated first torque command signal is output to the die cushion device body. When the second drive mode is selected by the drive mode selector, the slide is in a non-molding step. If it is in the area, the value calculated by the die cushion position command signal and the die cushion simulator Based on a second die cushion position signal indicating the position of the cushion pad, a second torque command for setting the position of the cushion pad calculated by the die cushion simulator to a position corresponding to the die cushion position command signal A die cushion position controller that generates a signal and outputs the generated second torque command signal to the die cushion simulator;
The die cushion simulator outputs at least the second die cushion position signal from among physical quantities calculated based on the second torque command signal output from at least the die cushion position controller,
The input / output selector is configured to input the first die cushion position signal to the die cushion position controller and to control the die cushion position when the first driving mode is selected by the driving mode selector. The first torque command signal generated by the device is output to the die cushion device body, and when the second drive mode is selected by the drive mode selector, the second die cushion position signal is The die cushion according to any one of claims 1 to 11, wherein the die cushion position controller inputs the second torque command signal generated by the die cushion position controller and causes the die cushion simulator to output the second torque command signal. Control device. The die cushion device main body has an angular velocity detector for detecting the angular velocity of the servo motor,
When the first drive mode is selected by the drive mode selector, the die cushion position controller, when the slide is in a non-molding process region, the die cushion position command signal and the die cushion Based on the first die cushion position signal indicating the position of the cushion pad detected by the position detector and the first angular velocity signal indicating the angular velocity of the servomotor detected by the angular velocity detector, the die cushion A first torque command signal is generated for setting the position of the cushion pad detected by the position detector to a position corresponding to the die cushion position command signal, and the generated first torque command signal is used as the die cushion device main body. When the second drive mode is selected by the drive mode selector, the slide is When in the molding process region, the die cushion position command signal, the second die cushion position signal indicating the position of the cushion pad calculated by the die cushion simulator, and the servo calculated by the die cushion simulator. Based on the second angular velocity signal indicating the angular velocity of the motor, a second torque command signal is generated for setting the position of the cushion pad calculated by the die cushion simulator to a position corresponding to the die cushion position command signal. And outputting the generated second torque command signal to the die cushion simulator,
The die cushion simulator includes at least the second die cushion position signal and the second angular velocity signal among physical quantities calculated based on at least the second torque command signal output from the die cushion position controller. Output
The input / output selector causes the die cushion position controller to input the first die cushion position signal and the first angular velocity signal when the first driving mode is selected by the driving mode selector. And when the first torque command signal generated by the die cushion position controller is output to the die cushion device body and the second drive mode is selected by the drive mode selector, the second The die cushion position signal and the second angular velocity signal are input to the die cushion position controller, and the second torque command signal generated by the die cushion position controller is output to the die cushion simulator. Item 15. A die cushion control device according to Item 12.   When the first drive mode is selected by the drive mode selector, the die cushion position controller uses the first die cushion position signal detected by the die cushion position detector as a position feedback signal. And the first angular velocity signal detected by the angular velocity detector is used as an angular velocity feedback signal for ensuring the dynamic stability of the position of the cushion pad, and the driving mode selector selects the second angular velocity signal. When the drive mode is selected, the second die cushion position signal calculated by the die cushion simulator is used as a position feedback signal, and the second angular velocity signal calculated by the die cushion simulator is The cushion calculated by the die cushion simulator Die cushion control apparatus according to claim 13 for use as an angular velocity feedback signal for ensuring the dynamic stability of the position of Npaddo. A cushion pad; a hydraulic cylinder that supports the cushion pad and generates a die cushion force when the slide of the press machine is lowered; and a hydraulic pump / motor that generates hydraulic fluid for driving the hydraulic cylinder; Based on a servo motor connected to the rotary shaft of the hydraulic pump / motor, a pressure detector for detecting the pressure of the cushion pressure generating side pressurizing chamber of the hydraulic cylinder, and an input first torque command signal A die cushion control method for controlling a die cushion device main body having a drive unit for driving the servo motor,
Selecting a second drive mode for driving a die cushion simulator that models the die cushion device main body;
When the second drive mode is selected, the die cushion pressure command signal indicating the die cushion pressure output from the die cushion pressure command device and the cushion pressure of the hydraulic cylinder calculated in real time by the die cushion simulator Based on the second die cushion pressure signal indicating the pressure in the generation side pressurization chamber, the pressure in the cushion pressure generation side pressurization chamber of the hydraulic cylinder calculated by the die cushion simulator is determined as the die cushion pressure command. Generating a second torque command signal having a pressure corresponding to the signal, and outputting the generated second torque command signal to the die cushion simulator;
When the second drive mode is selected, the die cushion simulator generates the generated second torque command signal, a slide position signal and a slide speed signal indicating the slide position and speed of the press machine. A step of outputting at least the second die cushion pressure signal in real time from physical quantities calculated in real time based on;
Based on at least the second die cushion pressure signal calculated from the second die cushion pressure signal or the second die cushion pressure signal calculated by the die cushion simulator, the second die cushion pressure signal or the Displaying the second die cushion pressure or the second die cushion force corresponding to the second die cushion force signal on the display unit and / or recording it on the recording unit;
The first die cushion device main body is driven when the second die cushion pressure or the second die cushion force displayed on the display and / or recorded on the recording unit is within an allowable range. Selecting a driving mode of
When the first drive mode is selected, a first die cushion pressure signal indicating the pressure in the cushion pressure generation side pressure chamber of the hydraulic cylinder detected by the die cushion pressure command signal and the pressure detector. Based on the above, the first torque command signal is generated so that the pressure in the pressurizing chamber on the cushion pressure generation side of the hydraulic cylinder detected by the pressure detector is a pressure corresponding to the die cushion pressure command signal. Outputting the generated first torque command signal to the die cushion device main body;
A die cushion control method including:

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