JPH10277798A - Servo press motion control device and control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the machining cycle time of a servo press by providing a servo motor control operating means to operate the speed command value of the servo motor and output the operated value to a servo motor command outputting means. SOLUTION: A position specification signal detector 23 detects the motion change of a slide as the torque change of a servo motor 11, and inputs the detected signal of the torque change in a specified position judging means 25. The specified position judging means 25 judges the motion change of the slide based on the size or the rate of change of the actual work torque. A servo motor control operating means 28 operates the speed command value of the servo motor 11 so that the position and the speed of the slide are the motion setting data stored in a motion storing means 24 and outputs the operated value. The maximum acceleration command or the maximum deceleration command of the servo motor 11 is outputted to a servo motor command outputting means 29 by the acceleration command or the deceleration command from a speed command operating means 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motion control device and a control method thereof capable of shortening a cycle time in machining a servo press in which a slide is driven directly by an electric servomotor.

[0002]

2. Description of the Related Art In recent years, as represented by electronic products, high-tech technology has been remarkable, and accordingly, its components have been required to have high-precision quality. In press working, various technical improvements have been made to meet such demands.For example, high-precision working that cannot be done with conventional hydraulic presses is performed by servo presses driven by servo motors. Is being done. For example, Japanese Patent Application Laid-Open No. 2-224898 discloses a technique relating to a press machine in which a stroke driven by a servomotor is stroke-controlled by a set control pattern. As shown in FIG. 8, the press machine includes a slide 15 that moves up and down on a frame 10. The slide 15 is connected to a servomotor 11 via a ball screw 14 (in the present invention, referred to as a power conversion device) and a speed reducer 12 (same as a rotation transmitting member), and is driven by the servomotor 11. The servo motor 1
Reference numeral 1 denotes a controller 20 (servo control device) via a servo amplifier 29 (servo motor command output means).
It is connected to the. The slide 15 driven by the servomotor 11 is subjected to motion control based on a control pattern input to the controller or a control pattern automatically set based on input processing conditions. As an example of this control pattern, an example of punching as shown in FIG. 9 is given. In this control, the slide 15 is driven from a rising end Z1 (in the present invention, indicated as an upper limit position) to a lowering end Z2 (same as the lower limit position) to perform punching. The rising end Z1 and the lowering end Z2 are performed.
The intermediate point Z3 is set between the two points, and another speed is set from the intermediate point Z3 to the descending end Z2, thereby performing more precise machining.

[0003]

However, it is very important to improve the processing accuracy and the product quality as a progress of production technology, but on the other hand, to shorten the processing time and improve the productivity. Improvement can be said to be very important in terms of production technology. In the prior art,
Although the slide control pattern for improving the processing accuracy is shown, from the viewpoint of shortening the processing time, the slide speed, which is a parameter for determining the control pattern, and the speed switching position or pressurizing time, etc. The conditions,
The slide needs to be set so as to perform machining at a shorter path and at a higher speed.

[0004] The present invention has been made in view of the above problems,
It is an object of the present invention to provide a servo press motion control device and a control method thereof for shortening a processing cycle time.

[0005]

Means for Solving the Problems, Functions and Effects In order to achieve the above object, the invention according to claim 1 comprises a slide 15 that moves up and down, a servomotor 11 that drives the slide 15 up and down, Slide position detecting means 17 and speed detecting means 11a for detecting the position and speed of the slide 15, setting / display means 18 for setting the position and speed conditions of the slide 15, and a speed command for the servo motor 11 based on the set conditions. Means for outputting a value, and servomotor command output means 29 for receiving the speed command value and controlling the servomotor 11. The motion control of the slide 15 is performed based on the predetermined position and speed data. In a motion control device of a servo press for processing a workpiece, when a die 2 starts pressurizing a workpiece during punching. A position specifying signal detector 23 for detecting a signal for specifying a pressing start position of the ride 15, and the pressurizing based on the rate of change or level of the signal detected by the position specifying signal detector 23. A specific position judging means 25 for detecting a start position and inputting position data from the slide position detecting means 17 at this time, and this position is determined based on the pressurization start position data input to the specific position judging means 25. Slide 1 above the specified distance
5, a position setting means 27 for setting a processing start position at which the descending speed is switched from the maximum speed to the processing speed, and processing start position data newly set by the position setting means 27 and input by the setting / display means 18. The motion storage means 24 for storing the position and speed conditions as slide control data, and the position and speed of the slide 15 detected during processing at the time of the next punching processing are stored in the slide control data stored in the motion storage means 24. And a servo motor control calculating means 28 for calculating a speed command value of the servo motor 11 and outputting the calculated speed command value to the servo motor command output means 29 so that a motion based on the servo motor 11 is obtained.

According to the first aspect of the present invention, the starting position of pressing the slide when the mold starts processing the workpiece is detected by a signal (for example, output torque, vibration acceleration, etc.) specifying the position. can do. Then, a new machining start position is set a predetermined distance above the pressurization start position, and the punching process is performed by lowering the slide at the maximum speed from the upper limit position to the newly set machining start position. In addition, the processing cycle time can be shortened, and the productivity can be improved.

[0007] The invention described in claim 2 is the first invention.
In the motion control device for a servo press described above, the specific position determining means 25 is provided with the position specifying signal detector 2.
Further, based on the temporal change rate or the level of the level of the signal detected by the step 3, the mold touch position of the slide 15 is detected, and the position data at this time is input from the slide position detecting means 17, The position setting means 2
Reference numeral 7 denotes a configuration of a servo press motion control device that sets a position that is a predetermined distance above the position as a new upper limit position for the second time or later based on the mold touch position data.

According to the second aspect of the present invention, the die touch position at which the slide contacts the die can be detected by a signal (for example, output torque, vibration acceleration, etc.) specifying this position. Then, a new upper limit position is set a predetermined distance above the detected die touch position, and the slide is lowered at the maximum speed to perform the punching process to the set new processing start position. ,
The slide can be moved down at a higher speed to a position closer to the pressing start position than before, while the process is shortened. As a result, the processing cycle time is shortened, and the productivity can be improved.

[0009] The invention described in claim 3 is the first invention.
In the motion control device for a servo press described above, the specific position determining means 25 is provided with the position specifying signal detector 2.
3. Based on the temporal change rate or level of the signal detected by the step 3, the punching of the slide 15 is further detected, and the servo motor control calculating means 28
Immediately after the punching, a command for reversely rotating the servomotor 11 is output to the servomotor command output means 29, so that the motion control device of the servo press raises the slide 15 from the punching position.

According to the third aspect of the present invention, the punching position where the slide completes the punching can be detected by a signal (for example, output torque, vibration acceleration, etc.) specifying this position. Then, when the punching is detected, the slide is immediately lifted, so that the process of the slide reaching the lower limit position after the punching is shortened. As a result, the processing cycle time is shortened, and the productivity can be improved.

Further, the invention according to claim 4 is a slide 15 which moves up and down, a servo motor 11 which drives the slide 15 up and down, a slide position detecting means 17 which detects the position and speed of the slide 15, and a speed detecting means. Means 1
1a, setting / display means 18 for setting the position and speed conditions of the slide 15, means for outputting a speed command value of the servomotor 11 based on the set conditions, and receiving the speed command value to control the servomotor 11 A servo motor command output means 29 for controlling the motion of the slide 15 based on the predetermined position and speed data to form a workpiece by the servo press motion control device. A motion storage means 24 for storing the position and speed conditions input by the display means 18 as slide control data, and a maximum speed after the slide 15 starts lowering from the upper limit position based on the slide control data of the motion storage means 24. Outputs an acceleration command to accelerate with the maximum torque until the maximum speed is reached. Speed command computation unit 26 outputs a deceleration command for decelerating at the maximum torque from the predetermined position of 置上 side
And the servo motor 1 such that the position and speed of the slide 15 detected during processing are a motion based on the slide control data stored in the motion storage means 24.
And a servo motor control calculating means 28 which calculates and outputs a speed command value of 1 and outputs a maximum acceleration command or a maximum deceleration command of the servo motor 11 in response to an acceleration command or a deceleration command from the speed command calculating means 26. Controlling the speed of the servo motor 11 based on the speed command value from the servo motor control calculating means 28, or changing the current value of the servo motor 11 to the maximum acceleration current or The servo motor command output means 29 for controlling the maximum deceleration current is provided.

According to the fourth aspect of the present invention, the slide descends while being accelerated with the maximum torque until reaching the maximum speed after the start of descending from the upper limit position and reaches the maximum speed. When the slide reaches the maximum speed, the slide is maintained at this speed and descends. Then, the slide descends from a predetermined position above the lower limit position while being decelerated with the maximum torque, and stops at the lower limit position. As a result, the acceleration and deceleration times of the slide in the descending step are shortened, so that the machining cycle time is shortened and the productivity can be improved.

The invention according to claim 5 is characterized in that the slide 15 which moves up and down, the servomotor 11 which drives the slide 15 up and down, the slide position detecting means 17 which detects the position and speed of the slide 15 and the speed detection Means 1
1a, setting / display means 18 for setting the position and speed conditions of the slide 15, means for outputting a speed command value of the servomotor 11 based on the set conditions, and receiving the speed command value to control the servomotor 11 A servo motor command output means 29 for controlling the motion of the slide 15 based on the predetermined position and speed data to form a workpiece by the servo press motion control device. A motion storage means 24 for storing the position and speed conditions input by the display means 18 as slide control data, and a maximum speed after the slide 15 starts ascending from the lower limit position based on the slide control data of the motion storage means 24. Outputs an acceleration command that accelerates with the maximum torque until the maximum speed is reached. Speed command computation unit 26 outputs a deceleration command for decelerating at the maximum torque from the predetermined position of 置下 side
And the servo motor 1 such that the position and speed of the slide 15 detected during processing are a motion based on the slide control data stored in the motion storage means 24.
And a servo motor control calculating means 28 which calculates and outputs a speed command value of 1 and outputs a maximum acceleration command or a maximum deceleration command of the servo motor 11 in response to an acceleration command or a deceleration command from the speed command calculating means 26. Controlling the speed of the servo motor 11 based on the speed command value from the servo motor control calculating means 28, or changing the current value of the servo motor 11 to the maximum acceleration current or The servo motor command output means 29 for controlling the maximum deceleration current is provided.

According to the fifth aspect of the present invention, in the ascending step after the slide reaches the lower limit position, the slide rises while being accelerated with the maximum torque until the maximum speed is reached after the start of the ascent, and when the slide reaches the maximum speed, the slide speed is increased. Rising maintained. Then, the slide rises from a predetermined position below the upper limit position while being decelerated with the maximum torque, and stops at the upper limit position. As a result, the acceleration and deceleration times of the slide in the ascending step are shortened, so that the machining cycle time is shortened and the productivity can be improved.

[0015] The invention described in claim 6 is the first invention.
In the motion control device for a servo press according to any one of (1) to (5), the position identification signal detector 23 detects an output torque based on a load current of the servomotor 11, and the vibration of the slide 15. Of the servo press motion control device, which is either an acceleration sensor for detecting the pressure or a sound pressure sensor for detecting the sound pressure at the time of contact between the slide 15 and the mold 2 or between the mold 2 and the workpiece. I have.

According to the invention described in claim 6, at least one of the mold touch position, the pressing start position and the punching position is determined by the specific signal detector, the rate of change of the actual working torque of the servomotor, and the slide. Or the magnitude of the sound pressure level at the time of contact between the slide and the mold or between the mold and the workpiece. Then, a predetermined distance above the detected die touch position is set as an upper limit position of the slide, a position above a predetermined distance from the pressing start position is set as a processing start position, or immediately after punching is detected, the slide is raised and the processing is performed. Do it. As a result, in the slide, the process from the upper limit position to the die touch position is shortened, the area of high speed descent is expanded in the section from the die touch to the start of pressing, or the process from the punching position to the lower limit position is omitted. Time can be shortened, and productivity can be improved.

According to a seventh aspect of the present invention, there is provided a servo for performing punching of a workpiece by controlling the position and speed of a slide 15 driven directly by a servomotor 11 based on a preset slide motion. In the press motion control method, the temporal change rate of the actual working torque of the servo motor 11 required to generate the pressing force of the slide 15, the vibration acceleration of the slide 15, or the distance between the slide 15 and the mold 2, Based on the magnitude of the sound pressure level at the time of contact or punching between the die 2 and the workpiece, at least one of the die touch position, the pressing start position, or the punching position of the slide 15 is detected. At the time of the punching process, a new upper limit position is set a predetermined distance above the detected die touch position, and descending from the upper limit position is started, or A new processing start position is set a predetermined distance above the pressure start position, and after the descent from the upper limit position to the processing start position at the maximum speed, the speed is reduced to the processing speed at the processing start position, or after the punching position is detected. This is a motion control method of a servo press in which the slide 15 is immediately raised to perform processing.

According to the seventh aspect of the present invention, at least the die touch position at which the slide contacts the die or the pressing start position at which the die starts processing of the workpiece is a signal specifying each position ( (For example, output torque, vibration acceleration, etc.). Then, the slide is lowered at the maximum speed from the newly set upper limit position that is a predetermined distance above the detected die touch position to a newly set processing start position that is a predetermined distance above the pressing start position. Since the punching is performed and the slide is raised immediately after the punching, the processing cycle time can be shortened, and the productivity can be improved.

According to an eighth aspect of the present invention, the workpiece is formed by controlling the position and speed of the slide 15 driven directly by the servomotor 11 based on a preset slide motion. In the motion control method of the servo press, the temporal change rate of the actual working torque of the servo motor 11 required to generate the pressing force of the slide 15, the vibration acceleration of the slide 15, or the distance between the slide 15 and the mold 2 The die touch position of the slide 15 is detected based on the magnitude of the sound pressure level at the time of contact, and a new upper limit position is set at a position above the detected die touch position by a predetermined distance during the second and subsequent forming operations. When the slide 15 is lowered from the upper limit position and / or when the slide 15 is raised from the lower limit position to the upper limit position, the highest speed Until reaching accelerated at the maximum torque, and a motion control method of a servo press for machining is decelerated at a maximum torque when reaches the maximum speed to maintain this rate and to stop from maximum speed.

According to the present invention, the slide descends while being accelerated with the maximum torque until reaching the maximum speed after the descent from the upper limit position to the maximum speed, and when the slide reaches the maximum speed, the slide is maintained at this speed and further descends. Thereafter, the vehicle descends from a predetermined position above the lower limit position while being decelerated with the maximum torque and stops at the lower limit position. And after holding the pressurization for a certain period of time, the slide rises while being accelerated with the maximum torque until it reaches the maximum speed after the start of rising from the lower limit position, and when it reaches the maximum speed, it is maintained at this speed and further rises,
From a predetermined position below the upper limit position, it rises while being decelerated with the maximum torque and stops at the upper limit position. By realizing such a motion, the slide acceleration and deceleration time in the descending process is reduced compared to the conventional basic motion of high-speed descent → low-speed descent → pressure holding → high-speed ascent. Performance can be improved.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of a main part of a servo press to which a mold is attached. The press 1 is equipped with a frame 10, a bolster 16 is horizontally disposed below the frame 10, and a mold 2 is mounted on an upper surface of the bolster 16. A servo motor 11 as a power source of the press 1 and a power conversion device 1 for converting the rotational force of the servo motor 11 into reciprocating motion are provided above the frame 10.
4 is attached. The servo motor 11 is provided with a speed detecting means 11a for detecting a rotation speed such as a pulse generator.
The rotation speed 1 is controlled by controlling the current by a servo control device 20 described later. The torque of the servo motor 11 is transmitted to the power converter 14 by a rotation transmitting member 12 such as a belt. The servo motor 11 may be either an AC motor or a DC motor.

The rotation transmitting member 12 may be a chain or a gear, or may be directly connected to the output shaft of the servomotor 11, and does not specify a transmitting means. In the present invention, the power conversion device 14 is also a ball screw. However, there are various methods using a screw mechanism, a combination of a worm gear and a worm wheel, or a combination of a pinion gear and a rack. It does not do. At the lower end of the power conversion device 14, a slide 15 that moves up and down at a position facing the bolster 16 is mounted, and when the slide 15 moves down from the upper limit position to the lower limit position, the mold 2 is pressed to process. Process things. Then, when the slide 15 reaches the lower limit position and finishes processing the workpiece, it moves up to the upper limit position.

The slide 15 and the bolster 16 are provided at predetermined positions with components of a slide position detecting means 17 composed of a linear sensor or the like. In other words, the slide position detecting means 17 controls the bolster 16 so that the axial direction is parallel to the vertical direction of the slide 15.
A linear scale 17a attached to the rear of the slide 15 and a detection head 17b attached to the rear of the slide 15 at a position facing the linear scale 17a. As the detection head 17b moves up and down with respect to the fixed linear scale 17a in accordance with the vertical movement of the slide 15, the position of the slide 15 is determined by the sensor incorporated inside the detection head 17b.
6 is detected as the height from the upper surface. The press working is performed by controlling the slide 15 under predetermined operating conditions. The operation control of the slide 15, ie, motion control, has a great influence on the working environment such as quality, work efficiency, noise and vibration. For this reason, the control condition setting of the slide 15 is a very important work in press working.

FIG. 2 is a functional block diagram showing an outline of the hardware configuration and control of the press machine according to the present invention. In press working, slide 15 which is a control condition
The operation speed, the switching position of this speed, the lower limit position, the pressurization time, and other data are set, and input from the setting / display means 18 to a servo controller 20 described later. The data is displayed on the setting / display means 18. Setting / display means 18
Comprises a set value input unit such as a setting switch, and a set value display unit for displaying input data by means such as a liquid crystal display screen or a CRT. The setting / display means 18 is provided with switches for selecting operation modes such as operation and condition setting, and for giving operation instructions such as automatic operation and manual operation.

The control data inputted from the setting / display means 18 is taken in and stored in the servo control device 20, and the slide 15 is stored in accordance with the processing procedure incorporated in advance.
Is performed. The servo control device 20 is configured by a general computer having functions of data storage, arithmetic processing, data display, data input / output, and the like. The central role of the motion control device according to the present invention is Is responsible for. The servo control device 20 controls the speed of the servo motor 11
And slide 1 detected by slide position detecting means 17
Based on the speed and position data of No. 5, the speed or torque command of the servo motor 11 is calculated and output so that the press 1 is operated under the set conditions. In response to this control command, the servo motor 11
Is controlled, the slide 15 performs a predetermined operation which is initially set, and presses the mold 2 to process the workpiece under predetermined conditions.

FIG. 3 is a functional block diagram showing details of the servo control device 20 of FIG. 2 relating to the motion control of the present invention. The position specifying signal detector 23 is for specifying a slide speed switching position such as a mold touch position or a pressing start position, and outputs, for example, a current from a servo motor command output unit 29 that controls the servo motor 11. The slide 15 includes a torque detector for detecting torque.
Is detected as a change in the torque of the servo motor 11. Then, the detection signal of the torque change at this time is input to the specific position determination unit 25. The position identification signal detector 23 is an acceleration sensor that detects the vibration of the slide 15 or a sound pressure that detects the sound pressure when the slide 15 contacts the mold 2 or when the mold 2 contacts the workpiece. A sensor or the like may be used.

Based on the output torque detected from the output motor current by the position identification signal detector 23, the specific position determining means 25 removes the torque required for accelerating, decelerating, and maintaining the constant speed of the slide 15 from the output torque. To obtain the actual working torque. The actual working torque can be calculated from the motor current value by, for example, the following method. Load inertia constant for calculating acceleration or deceleration torque, speed resistance torque proportional constant for calculating constant speed maintaining torque, friction torque constant, and torque constant representing the relationship between motor output current and output torque, etc. Are stored. At the time of acceleration or deceleration, a required motor output current value is obtained based on a required acceleration value or deceleration value and each of the above constant data, and the required motor output value obtained from the motor current value detected by the current sensor is obtained. The actual work torque during acceleration / deceleration is calculated by subtracting the current value. Similarly, at the time of constant speed, the required motor output current value is obtained based on the speed value to be maintained at this time and the above constant data, and the required motor output current value obtained from the actual motor output current value is obtained. The actual work torque at constant speed can be calculated by subtracting the value.

The specific position determining means 25 determines a change in the motion of the slide 15 based on the magnitude or rate of change of the actual work torque. When detecting this motion change by the actual working torque of the servo motor 11, for example, when the slide 15 punches out the workpiece,
Since the pressing force of the slide 15 suddenly decreases, this decrease in the pressing force is detected as a sudden decrease in the actual working torque of the servomotor 11. The specific position determining means 25 stores in advance the actual work torque reduction rate (hereinafter, referred to as the torque reduction rate) at the time of punching the workpiece, and is detected by the position identification signal detector 23 during processing. When the torque reduction rate obtained from the output torque is significantly smaller than the stored torque reduction rate, it is determined that punching is performed. Then, the specific position determination unit 25 fetches the position of the slide 15 at the time of determining punching from the slide position detection unit 17 and transmits the position to the position setting unit 27. A change in the slide motion similar to the punching is detected when the slide 15 touches the mold 2, when the mold 2 touches the workpiece, or when the workpiece is punched.

The position setting means 27 newly sets a speed switching position based on the specified position. That is, a position that is a predetermined distance above the specified mold touch position or the pressing start position is set as a new speed switching position (for example, a switching position from a high-speed descending speed to a low-speed descending speed, or a switching position from a low-speed descending speed to a processing speed). Set. And
The newly set position data is fed back to the motion storage means 24 and stored. Further, the speed command calculating means 26 calculates the position of the slide 15 based on the position and speed data stored in the motion storage means 24.
Is accelerated with the maximum torque until the maximum speed is reached after the start of descending from the upper limit position, and after reaching the maximum speed, an acceleration / deceleration command is issued so as to be decelerated with the maximum torque from a predetermined position above the lower limit position. Further, the speed command calculating means 26
The acceleration / deceleration is performed so that the slide 15 is accelerated from the lower limit position to the maximum speed after the start of ascending until reaching the maximum speed, and after reaching the maximum speed, is decelerated from the predetermined position below the upper limit position by the maximum torque. Issue a command.

Then, the servo motor control calculating means 28
Calculates and outputs the speed command value of the servo motor 11 so that the position and speed of the slide 15 detected during machining become the motion setting data stored in the motion storage means 24. , The speed command calculating means 26
Receives acceleration command or deceleration command from the
The maximum acceleration command or the maximum deceleration command is output to the servo motor command output means 29. The servo motor command output means 29 is composed of a general-purpose device such as a servo amplifier, for example, so that the deviation between the input speed command value and the speed feedback signal detected by the speed detecting means 11a is reduced. By controlling the drive current, the slide 15 is controlled to a predetermined motion.
Further, when a maximum acceleration command or a maximum deceleration command is input, the servo motor command output means 29 controls the current so that the maximum motor current flows to accelerate or decelerate.
The display means 30 is composed of a liquid crystal display, a CRT display device, or the like, and displays the input and operation data when setting the motion of the slide 15, the control conditions set in the motion storage means 24, and the control data during operation. Thus, the operator can easily set the control conditions and monitor the operation.

The first and second embodiments of the method for controlling the motion of the slide 15 will be described with reference to FIGS. The first embodiment is an example of a punching process involving shearing of a workpiece, and the second embodiment is an example of a coining process such as engraving a stamp on the workpiece.

First, the punching process according to the first embodiment will be described with reference to FIGS. FIG. 4 is an example of a control curve of motion control according to the present invention. The vertical axis indicates the slide position, the slide speed, and the output torque of the servomotor, which are control parameters, and the horizontal axis indicates the elapsed time after the start of the slide operation. Slide 15
It descends at the maximum speed V00 from the upper limit position Z00, which is a predetermined distance above the die touch position Z10 that contacts the die, to the processing start position Z20, which is a predetermined distance above the pressing start position Z30. The upper limit position Z00 at this time is automatically set based on the mold touch position, and is set to a position closer to the mold touch position Z10 than the initially set upper limit position Z99 in consideration of a safe distance for manual work. Is done. As a result, the descent time of the slide 15 is reduced. And slide 1
5 further performs punching by descending from the processing start position Z20 at a predetermined processing speed V10. At this time, the punching position Z40 is detected. The machining start position Z20 is:
As in the case of the mold touch, the pressing start position Z30
It is automatically set to a predetermined distance above, and is set to a position closer to the pressing start position Z30 than the processing start position Z29 initially set in consideration of the safety distance. As a result, the machining start position Z20 and the machining start position Z29 at the time of initial setting are set.
The high-speed descending area of the slide 15 is expanded by the distance of the difference from the above, and the descending time is shortened.

When the punching is detected, the slide 15
From the punching position Z40 to the upper limit position Z00 immediately at the maximum speed V00 to complete the machining cycle. The punching is performed by comparing a predetermined reference value of a torque reduction rate at the time of punching with respect to the workpiece and a detected torque reduction rate of the servomotor. It is specified when the value has greatly decreased from the determination reference value. After punching, the slide 15
Reaches the lower limit position set as the control condition and rises. However, in the control method according to the present invention, the slide 1
Since 5 rises immediately after punching, the step of reaching the lower limit position is omitted, and the processing time for this distance is shortened. Further, as described above, the upper limit position Z00 is lower than the upper limit position Z99 at the time of the initial setting.
Rise time is also reduced. As described above, the speed switching position in each of the high speed descent, the pressure descent and the high speed ascent is automatically set, and the process of the slide 15 is shortened or reduced, or the high speed process is expanded.
The processing cycle time is reduced from t99 to t00.

Next, the method of motion control will be described with reference to the flowchart of FIG. 5 for setting control conditions for motion control and with reference to FIG. First, as shown in FIG. 5, initial conditions are set in a first step S1. The condition data includes the upper limit position Z99, the processing start position Z29, and the lower limit position Z50 as the position data of the slide 15, the maximum speed V00 and the processing speed V10 as the speed data of the slide 15, and the servo motor 11 at the time of punching. Torque reduction rate (ΔT
b / Δt). Of the above data, the upper limit position Z99 of the slide 15 is a safe upper position not in contact with the mold, and the processing start position Z29 is the mold touch position Z.
10 and above the pressurization start position Z30, and the lower limit position Z50 is a position where punching is reliably performed. The processing speed V10 is set to a value appropriate for the workpiece from experience and the like. Further, the torque reduction rate ΔTb / Δt at the time of punching the workpiece is obtained in advance by a test or by converting the pressing force data of the slide 15 already obtained into the actual working torque value of the servomotor 11. These setting data are stored in the setting / display means 18.
And stored in the motion storage means 24 of the servo control device 20.

In the next step S2, the operation of the press 1 is started, and the slide 15 descends from the initial upper limit position Z99 to the machining start position Z29 at the maximum speed V00.
In step S21 of the descending process, the slide 15
Detects a mold touch position Z10 that contacts the upper surface of the mold.
At the mold touch position Z10, the slide 15 instantaneously hits the mold, and the pressing force of the slide 15 suddenly increases. The actual working torque of the servo motor 11 driving the slide 15 is also rapidly increased by this mold touch. At this time, the position specifying signal detector 23 detects a torque change and transmits the torque value at this time to the specific position determining means 25.
The specific position determination means 25 calculates a torque change rate from the torque value, determines a mold touch from the magnitude of the change rate, and takes in the mold touch position Z10 of the slide 15 at this time from the slide position detection means 17. And position setting means 27
To communicate.

In step S22, as shown in FIG. 4, the position setting means 27 uses the algorithm incorporated therein to set a new upper limit position Z00 of the slide 15 above a predetermined minute distance above the mold touch position Z10. Set. The upper limit position Z00 is calculated using the calculation formula “Z00 = Z00 =
Z10 + α ", or set by calculating an upper position by a predetermined ratio dimension proportional to the thickness of the workpiece. Here, the coordinates of the position are positive upward and negative downward, and so on. Therefore, the upper limit position Z00 is larger than the mold touch position Z10 by α.
Only the upper position. In the next step S23, the upper limit position Z00 obtained by the position setting means 27 is input to the motion storage means 24 of the servo controller 20, and is replaced with the upper limit position Z99 stored as an initial set value. .

In the pressure lowering step of step S3,
The slide 15 is moved from the processing start position Z20 to the lower limit position Z50.
Toward the machining speed V10. At this time, in step S31, a pressurization start position Z30 at which the slide 15 starts pressurizing the workpiece when the pressure is lowered is detected, and then steps S32 and S33 are executed. That is, in step S31, when the slide 15 starts pressurizing the workpiece, the position specifying signal detector 23 detects the start of pressurization of the slide 15 in the same manner as in the case of the mold touch, and outputs the detection signal. Specific position determining means 25
Captures the pressurization start position Z30. And step S32
Then, the position setting means 27 sets the machining start position Z20 a predetermined minute distance above the pressurization start position Z30 by an algorithm incorporated in itself.

The processing start position Z20 is calculated by the formula “Z” in consideration of the maximum error β such as the thickness and flatness of the workpiece, in the same manner as the method for obtaining the mold touch start position Z10.
20 = Z30 + β ". Further, the processing start position Z20 may be a position above by a predetermined ratio of distance in proportion to the thickness of the workpiece. Next step S3
In step 3, the set machining start position Z20 is input to the motion storage means 24 of the servo controller 20, and is replaced with the machining start position Z29 stored as an initial set value.

In the next step S4, when the slide 15 reaches near the lower limit position Z50, the workpiece is punched. At this time, the specific position determination unit 25 compares the torque reduction rate detected by the position specification signal detector 23 with a preset reference value of the torque reduction rate, and determines the detected torque reduction rate as It is determined that the punching is performed when the value greatly decreases from the reference value. In step S5, when the punching is completed, a reverse rotation command of the servomotor 11 is issued by the servo motor control calculating means 28, and the slide 15 immediately rises from the punching position Z40 to the upper limit position Z00 at the maximum speed V00, and the punching process is performed. Complete the cycle. The second and subsequent punching processes are performed using the position control data updated first in this manner. In addition, the condition setting may be performed by another method, for example, the condition may be set for each processing shot and fed back at the time of the next processing, or the condition may be set for each shot at predetermined intervals.

Next, the case of coining processing according to the second embodiment will be described with reference to FIGS. The hardware configuration and functional block diagram are the same as in the case of punching. FIG. 6 is an example of a control curve of motion control according to the present invention. In this drawing, FIG.
The same reference numerals denote the same components and meanings, and a description thereof will be omitted. Here, the vertical axis indicates the slide position, the slide speed, and the output torque of the servomotor, which are control parameters, and the horizontal axis indicates the elapsed time after the start of the slide operation.

The slide 15 descends at a maximum speed V00 from an upper limit position Z00, which is a predetermined minute distance above a mold touch position Z15 that contacts the mold, to a lower limit position Z50. At this time, until the maximum speed V00 is reached, a command for accelerating the slide 15 with the maximum torque is output by the speed command calculating means, and in response to this command, the servo motor control calculating means issues a command for maximizing the servo motor to the servo motor. Output to the command output means. Then, a command for setting the current value of the servo motor to the maximum acceleration current is issued by the servo motor command output means, and the slide 15 descends at the maximum acceleration. When the slide 15 reaches the maximum speed V00, it keeps this speed and descends.

Then, at a predetermined position above the lower limit position Z50, a command to decelerate the slide 15 with the maximum torque is issued from the speed command calculating means, and the slide 15 reaches the lower limit position Z50 while descending at the maximum deceleration. I do. The position of the slide 15 at which the maximum deceleration command is issued is obtained by calculating the deceleration distance required when the speed is reduced by the maximum torque by the speed command calculation means. Then, the slide 15 is controlled as in the case of the acceleration. In this descending step, the upper limit position Z00 of the slide 15 is automatically set a predetermined distance above the mold touch position, as in the case of the punching, and the mold touch position is higher than the upper limit position Z99 initially set in consideration of the safety distance. Z
It is reset to a position close to 10. As a result, slide 1
5 is shortened and the descent time is shortened by acceleration and deceleration at high speed, so that the machining cycle time is shortened.

When the slide 15 reaches the lower limit position Z50, the pressing force is maintained for a predetermined time t50. Slide 15
After the pressurization and holding is completed, the ascent rises while being accelerated to the maximum as in the case of the high-speed descent. Then, when the slide 15 reaches the maximum speed V00, the slide 15 maintains this speed and rises. At a predetermined position below the upper limit position Z00, the slide 15 is decelerated at the maximum torque as in the case of the high-speed descent. It reaches the upper limit position Z00. The control of the slide 15 in the ascending step is performed by the same procedure and method as in the case of the high-speed descending. Thus, the machining cycle of coining is completed. In this way, while reducing the distance of the machining cycle of the slide 15,
By expanding the region of the maximum speed V00, the machining cycle time is reduced from the time t19 under the initial condition to the time t10 under the new condition. Also, as compared with the machining cycle time based on the conventional motion curve, the slide 15 cannot be switched to the low speed at the time of pressurization, so the machining cycle time is further reduced from t29 to t10.

Next, a method of motion control will be described with reference to a flowchart for setting control conditions for motion control shown in FIG. In each of the drawings, the same reference numerals as those in the drawing in the case of the punching represent the same configuration and meaning, and description thereof will be omitted. First, in the first step S10, initial conditions are set. The condition data includes the upper limit position Z99 and the lower limit position Z50 as the position data of the slide 15, the maximum speed V00 as the speed data of the slide 15, and the lower limit position Z50.
Is set at time t0.

Then, the machining cycle is started, and step S
In step 11, a command for maximum acceleration of the slide 15 is output by the speed command calculation means 26, and the slide 15 descends while being accelerated by the maximum torque of the servomotor 11.
In the next step S12, the slide 15 has the maximum speed V0.
When it reaches 0, it descends further while maintaining the speed.
While the slide 15 is descending at the maximum speed V00, the next step S2 is executed. This step S2 and the following steps S21 to S23 are the same as in the case of the punching. That is, the mold touch position Z10 is detected, and a new upper limit position Z00 of the slide 15 is set above the position Z10 by a predetermined minute distance. This upper limit position Z00 is stored in the motion storage means 24 as an initial setting value. Is replaced with the upper limit position Z99.

Then, in step S13, when the slide 15 reaches a deceleration start position that is a predetermined distance above the lower limit position Z50, a command for maximum deceleration is output by the speed command calculation means 26. Based on this command, slide 15
Falls while being decelerated by the maximum torque of the servo motor 11. Then, when the slide 15 reaches the lower limit position Z50, in step S14, the workpiece is moved for a predetermined time t.
The pressure is then increased to 50 and the next ascent process is started. Step S15
Then, the slide 15 rises while being accelerated in the same manner as in the case of the acceleration and descent. In the next step S16,
When the slide 15 reaches the maximum speed V00, in step S17, the slide 15 keeps rising while maintaining this speed V00. Then, in step S17, when the slide 15 reaches the deceleration start position a predetermined distance below the upper limit position Z00 by the speed command calculating means 26, a deceleration command is output in the same manner as in the case of deceleration and descent, and the slide 15 is decelerated with the maximum torque. While reaching the upper limit position Z00. The second and subsequent coining processes are performed based on the upper limit position data thus updated for the first time. In addition, the condition setting may be performed by another method, for example, the condition may be set for each processing shot and fed back at the time of the next processing, or the condition may be set for each shot at predetermined intervals.

By performing the motion control of the slide 15 as described above, the upper limit position is reset near the upper part of the mold touch position, or the processing start position is set closer to the upper part of the pressing start position. The setting is reset, and the newly set upper limit position and the processing start position are lowered at the maximum speed. Further, the slide is raised immediately after the punching occurs. Further, the slide is accelerated to the maximum speed until it reaches the maximum speed, and is decelerated from the maximum acceleration to the maximum speed. Regarding a control method for maximizing acceleration or deceleration of the slide,
In the case of the present invention, the case of coining is used,
The control can be performed at a high speed during the punching process. Therefore, the processing cycle time in the punching and coining processes is reduced, and the productivity can be improved. Such control can be applied not only to punching and coining, but also to various presses such as cutting, bending, and drawing. Further, the maximum speed V00 of the slide 15 is not limited to the maximum speed of the servo press to be used depending on required processing conditions, and the speed value may be appropriately changed in some cases. In the above example, the specific position of the slide 15 is detected by a change in the torque of the servomotor 11, but may be detected by an acceleration level by an acceleration sensor, a sound pressure level by a sound pressure sensor, an amplitude level by a vibration sensor, or the like. .

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a servo press according to the present invention.

FIG. 2 is a functional block diagram showing an outline of a hardware configuration and control of the press machine according to the present invention.

FIG. 3 shows a functional block diagram of a servo control device according to the present invention.

FIG. 4 shows a control curve of motion control according to the present invention.

FIG. 5 shows a flowchart of setting control conditions for motion control according to the present invention.

FIG. 6 shows a control curve of motion control according to the present invention.

FIG. 7 shows a flowchart of a control method of motion control according to the present invention.

FIG. 8 shows a schematic view of a press machine.

FIG. 9 shows an example of a slide motion of a press.

[Explanation of symbols]

 Reference Signs List 1 press 2 mold 10 frame 11 servo motor 11a speed detecting means 12 rotation transmitting member 14 power conversion device 15 slide 16 bolster 17 slide position detecting means 17a linear scale 17b detection head 18 setting / display means 20 servo control device 23 position specifying signal Detector 24 Motion storage means 25 Specific position determination means 26 Speed command calculation means 27 Position setting means 28 Servo motor control calculation means 29 Servo motor command output means 30 Display means

Claims (8)

[Claims] A slide (15) that moves up and down, and a slide (1).
5) Servo motor (11) for driving up and down, and slide position detecting means for detecting the position and speed of slide (15), respectively.
(17) and speed detecting means (11a), setting and displaying means (18) for setting the position and speed conditions of the slide (15), and outputting the speed command value of the servo motor (11) based on the setting conditions. And a servo motor command output means (29) for controlling the servo motor (11) in response to the speed command value. The motion control of the slide (15) is performed based on the predetermined position and speed data. In the servo press motion control device that processes the workpiece by performing the process, the press start position of the slide (15) when the die (2) starts pressurizing the workpiece is specified during the punching process. A position specifying signal detector (23) for detecting a signal for detecting the pressurization start position based on a rate of change or a level of a signal detected by the position specifying signal detector (23), At this time, the position data is stored in the slide position detecting means (17). Based on the specific position determining means (25) to be input, and the pressurization start position data input to the specific position determining means (25), the descending speed of the slide (15) is higher than the position by a predetermined distance. A position setting means (27) for setting a processing start position at which the speed is switched to the processing speed, and processing start position data newly set by the position setting means (27) and input by the setting / display means (18). A motion storage means (24) for storing the position and speed conditions as slide control data, and a slide (1) detected during machining at the next punching process.
The speed command value of the servo motor (11) is calculated and the servo motor command output means (29) so that the position and speed of (5) become a motion based on the slide control data stored in the motion storage means (24). ), And a servo motor control operation means (28) for outputting to the servo press motion control device. 2. The motion control device for a servo press according to claim 1, wherein said specific position determining means (25) is a temporal change rate or level of a signal detected by said position specifying signal detector (23). Furthermore, based on the size of the slide, the mold touch position of the slide (15) is detected, and the position data at this time is input from the slide position detection means (17), and the position setting means (27) A motion control device for a servo press, wherein a position above a predetermined distance from the position is set as a new upper limit position for the second and subsequent times based on mold touch position data. 3. The motion control device for a servo press according to claim 1, wherein said specific position determining means (25) is a temporal change rate or level of a signal detected by said position specifying signal detector (23). Further, based on the size of the punch, the punching of the slide (15) is further detected, and the servomotor control calculating means (28) outputs a command to reversely rotate the servomotor (11) immediately after the punching, as a servomotor command output. A motion control device for a servo press, wherein the motion is output to a means (29) to raise the slide (15) from the punching position. 4. A slide (15) that moves up and down, and a slide (1).
5) Servo motor (11) for driving up and down, and slide position detecting means for detecting the position and speed of slide (15), respectively.
(17) and speed detecting means (11a), setting and displaying means (18) for setting the position and speed conditions of the slide (15), and outputting the speed command value of the servo motor (11) based on the setting conditions. And a servo motor command output means (29) for controlling the servo motor (11) in response to the speed command value. The motion control of the slide (15) is performed based on the predetermined position and speed data. In the motion control device of the servo press that performs the forming process of the workpiece by performing, the motion storage means (24) that stores the position and speed conditions input by the setting and display means (18) as slide control data, Based on the slide control data of the motion storage means (24), output an acceleration command to accelerate with the maximum torque until the slide (15) reaches the maximum speed after the descent from the upper limit position, and after the slide (15) has reached the maximum speed A speed command calculating means (26) for outputting a deceleration command for decelerating at the maximum torque from a predetermined position above the lower limit position; and a position and speed of the slide (15) detected during machining are stored in the motion storage means (24 ) Calculates and outputs a speed command value of the servo motor (11) so as to be a motion based on the slide control data stored in), and receives an acceleration command or a deceleration command from the speed command calculating means (26). A servo motor control calculating means (28) for outputting a maximum acceleration command or a maximum deceleration command of the servo motor (11), and a speed of the servo motor (11) based on a speed command value from the servo motor control calculating means (28). Control, or
A servo motor command output means (29) for controlling a current value of the servo motor (11) to a maximum acceleration current or a maximum deceleration current based on the maximum acceleration command or the maximum deceleration command. Motion control device. 5. A slide (15) that moves up and down, and a slide (1).
5) Servo motor (11) for driving up and down, and slide position detecting means for detecting the position and speed of slide (15), respectively.
(17) and speed detecting means (11a), setting and displaying means (18) for setting the position and speed conditions of the slide (15), and outputting the speed command value of the servo motor (11) based on the setting conditions. And a servo motor command output means (29) for controlling the servo motor (11) in response to the speed command value. The motion control of the slide (15) is performed based on the predetermined position and speed data. In the motion control device of the servo press that performs the forming process of the workpiece by performing, the motion storage means (24) that stores the position and speed conditions input by the setting and display means (18) as slide control data, Based on the slide control data of the motion storage means (24), an acceleration command for accelerating with the maximum torque is output until the slide (15) reaches the maximum speed after the start of ascending from the lower limit position. A speed command calculating means (26) for outputting a deceleration command for decelerating at the maximum torque from a predetermined position below the ascending position; and a position and speed of the slide (15) detected during machining are stored in the motion storage means (24). ) Calculates and outputs a speed command value of the servo motor (11) so as to be a motion based on the slide control data stored in), and receives an acceleration command or a deceleration command from the speed command calculating means (26). A servo motor control calculating means (28) for outputting a maximum acceleration command or a maximum deceleration command of the servo motor (11), and a speed of the servo motor (11) based on a speed command value from the servo motor control calculating means (28). Control, or
A servo motor command output means (29) for controlling a current value of the servo motor (11) to a maximum acceleration current or a maximum deceleration current based on the maximum acceleration command or the maximum deceleration command. Motion control device. 6. The motion control device for a servo press according to claim 1, wherein the position identification signal detector (23) outputs an output torque based on a load current of the servomotor (11). Torque detecting means for detecting the acceleration, an acceleration sensor for detecting the vibration of the slide (15), or
A motion control device for a servo press, which is a sound pressure sensor for detecting a sound pressure at the time of contact between the slide (15) and the mold (2) or between the mold (2) and the workpiece. . 7. Motion control of a servo press for punching a workpiece by controlling the position and speed of a slide (15) linearly driven by a servo motor (11) based on a preset slide motion. In the method, the time rate of change of the actual working torque of the servo motor (11) required to generate the pressing force of the slide (15),
(15) Vibration acceleration, or slide (15) and mold (2)
At least the slide (15) based on the magnitude of the sound pressure level at the time of contact or punching between the die (2) and the workpiece
Detects any one of the mold touch position, pressurization start position, and punching position, and sets a new upper limit position a predetermined distance above the detected mold touch position during the second and subsequent punching operations. From the upper limit or a new starting position at a predetermined distance above the pressing start position. Or
A motion control method for a servo press, wherein a slide (15) is raised immediately after a punching position is detected to perform machining. 8. Motion control of a servo press for forming a workpiece by controlling the position and speed of a slide (15) driven linearly by a servo motor (11) based on a preset slide motion. In the method, the time rate of change of the actual working torque of the servo motor (11) required to generate the pressing force of the slide (15),
(15) Vibration acceleration, or slide (15) and mold (2)
Slide based on the magnitude of the sound pressure level during contact between
The mold touch position of (15) is detected, and in the second and subsequent molding processes, a new upper limit position is set at a position above the detected mold touch position by a predetermined distance, and the slide (15) is moved from this upper limit position. When lowering and / or ascending from the lower limit position to the upper limit position, accelerate with the maximum torque until the maximum speed is reached, maintain this speed when the maximum speed is reached, and when stopping from the maximum speed. A motion control method for a servo press, characterized in that machining is performed with deceleration at a maximum torque.