JPH0773763B2 - Work feeder control device - Google Patents

Description

Description: [Industrial application] The present invention relates to a work feeder device for automatically loading and unloading a work in an automatic press machine in association with the movement of the press machine, and has particularly high reliability. The present invention relates to a feeder control device.

[Prior Art] Conventionally, in order to automatically carry in and carry out a work in an automated press system, it is operated by a contact signal from a rotary cam switch that rotates mechanically in conjunction with the crank rotation of the press and a mechanical link structure. It performed the functions of lateral movement, vertical movement, and clamp / unclamp operation mechanism. That is, for example, the start of a work feeder (hereinafter referred to as a feeder) is started by a signal from a limit switch that works when the crank angle of the press machine reaches a predetermined angle, and the feeder is set to carry in and carry out work in advance. Performed by mechanical action. Further, the fact that the operation of the feeder has reached a predetermined position is detected by a limit switch or the like and transmitted to the press machine to start the next operation of the press machine.

However, in the above-mentioned means, it is necessary to confirm that a predetermined motion has been completed in consideration of the temporal variation of the mechanical motion and to move to the next motion. Since there is a limit, in order to increase the operating speed of the press machine system and to perform reliable control, it is necessary to more accurately correspond the movement of the feeder device to the crank angle of the press. A sensor such as a servo mechanism that correctly electrically controls the position of a predetermined feeder mechanism corresponding to the crank angle measured by a sensor that accurately detects the crank angle, for example, a synchro oscillator, has come to be used. .

Next, a circuit for controlling the above movement will be described with reference to FIG.

In FIG. 6, reference numeral 32 is a synchro oscillator attached to the crank rotation shaft of the press and capable of measuring the rotation angle of the crank absolutely, and 33 is a conversion circuit for converting the angle signal from the synchro oscillator into a digital code. is there. The measured value of the crank angle of the press converted into a digital code is input to the computer 31 for control. Each position information of the clamp axis is read out and a position command signal is created. 38 is a synchro oscillator for position detection, which is attached to each of the three moving axes of the feeder. In the figure, only one axis is shown and the other two axes are the same, so they are omitted. The position information of, for example, the feeder axis measured by the synchro oscillator is converted into a digital code by a conversion circuit 39 for converting the angle signal from the synchro oscillator into a digital code and input to a control computer 31. The position information of the feeder shaft inputted to the computer 31 is compared with the previously prepared position command signal to prepare a deviation signal, and the position of the feed shaft previously recorded in the storage device in correspondence with the crank angle. Similarly to the information, a speed command signal for the feeder shaft drive motor corresponding to the deviation signal, which is predetermined and recorded in the storage device, is created by a digital code and output. The speed command signal of the feeder shaft drive motor output from the computer 31 is converted into an analog signal by the digital-analog conversion circuit 34, and then amplified by the servo amplifier 35 to an appropriate power to drive the servo motor 36. The servomotor 36 drives the feed shaft and at the same time the rotation speed of the servomotor is measured by a tachogenerator 37 that is mechanically coupled,
The measured value of the rotation speed is returned to the servo amplifier 35 to form a feedback loop to stably control the motor rotation.
The feed shaft driven by the servo motor 36 is coupled with the synchro oscillator 38 for detecting the position information of the feed shaft described above, and the correct current position of the feed shaft is measured and input to the control computer. Therefore, the feeder can be controlled according to the crank angle of the press according to a predetermined condition.

[Problems to be Solved by the Invention] According to the above-described means for controlling the movement of each part of the feeder mechanism by a servo mechanism or the like so as to move to a predetermined position in accordance with the crank angle in the operation of the press machine. However, it is possible to perform efficient work without wasting time in the processing operation by the press machine, but when an abnormality occurs in the crank angle detection mechanism described above, the press machine and the feeder interfere with each other. There was the problem of a big accident.

An object of the present invention is to solve the above-mentioned problems and to provide a safe work feeder device in which the press machine and the feeder do not interfere with each other even when an error occurs in the crank angle detection mechanism.

[Means for Solving the Problems] The present invention solves the above-mentioned problems and enables high-speed and efficient press work, and the press machine and the feeder do not interfere even when an error occurs in the crank angle detection mechanism. In a work feeder that corresponds to the crank rotation angle of the press machine and moves in a three-dimensional direction to automatically carry in and carry out a work to be processed by the press machine to a predetermined processing position on the press machine. , The crank angle detection mechanism of one system detects the crank angle for controlling the loading / unloading device that carries in / out the work feeder, and the crank angle detection mechanism of the other system controls the work feeder itself. While detecting the crank angle, the angle signal from the crank angle detection mechanism of one system and the angle from the crank angle detection mechanism of another system And a control device for stopping the operation of at least the work feeder when a deviation of a predetermined amount from the frequency signal occurs.

[Operation] In the present invention, in the work feeder, which corresponds to the crank rotation angle of the press machine, moves in a three-dimensional direction and automatically carries in and carries out a work to be processed by the press machine to a predetermined processing position on the press machine. Since the crank angle detection mechanism of the two-system press machine is provided, and the operation of the work feeder is stopped when a deviation occurs in the detection angle of the two-system crank angle detector, an error occurs in the crank angle detection mechanism. It is possible to obtain an excellent effect of preventing the press machine and the work feeder from interfering with each other even when the above occurs.

[Embodiment] An embodiment of the work feeder control device according to the present invention will be described below with reference to the drawings.

FIG. 1 is a view in which an automatic press machine and a work feeder device are combined, and FIG. 2 is a view in which the work feeder device and the lower structure of the press are viewed obliquely from above. FIG. 3 shows a schematic view of the feeder portion of the work feeder taken out and its movement, and FIG. 4 shows the movement of each axis of the feeder corresponding to the crank angle of the press. Further, FIG. 5 shows a block diagram of a circuit of the work feeder control device according to the present invention.

In FIG. 1, 1 is a press main body, 2 is an upper mold which is suspended from a crankshaft, and which presses a work placed between the lower mold 3 and a lower mold 3 by applying force. 4 is an instrument for displaying the crank angle of the press, which is operated by a signal from a synchro oscillator attached to the crankshaft to detect the crank angle and generate a command signal to the work feeder. Has been.

Reference numeral 5 denotes a work feeder 5 that moves left and right in the drawing to carry in and carry out a work. Reference numerals 6 and 7 denote cylinders for vertically moving the work feeder 5.
-B, 7-b, the cylinders 6, 7 are the work feeder 5
5b shows the situation where the work feeder 5 is moved up by the cylinders 6 and 7 and is moved to the left by a mechanism for moving the frame left and right, which is omitted in the drawing, Shows.

In FIG. 1, reference numeral 3 denotes a lower mold 3 attached to a lower structure of the press 1, and a work to be processed is carried into a predetermined place on the lower mold 3 by a work feeder 5.

In FIG. 2, feeders 5-1 and 5-2 show that the work feeder 5 described in FIG. 1 is provided in two rows before and after the press 1, and the work to be processed is omitted in the figure. The two workpiece feeders 5 are held by the iron hands provided to face each other, and the workpieces are held in and carried out.

Reference numeral 8 is a driving body for moving the work feeder 5 left and right, which is omitted in FIG. 1, and 9 is a driving body for moving the work feeder 5 back and forth to clamp and unclamp the work.

In FIG. 3a, 5-1 and 5-2 are the work feeders 5 described above, and 10-1, 10-2, and 10-3 are irons for conveying the work between the molds omitted in FIG. In the figure, three hands are attached to the work feeder 5 at equal intervals. The reason why three iron hands are provided is to move three works simultaneously in one movement.

FIG. 3b shows the movement of the work feeder 5 described above. That is, the clamped work moves to the right in the drawing at the timing of a1 and is carried in between the press dies, and b1
When the work feeder 5 unclamps at the timing of c1 and the work feeder 5 unclamps at the timing of c1, the work feeder 5 returns to the left at the height of its side at the timing of 2a, and at the same time it clamps the next work at the timing of c2. The adjacent iron hand clamps the work machined by press 1 during timing a2. When the work is clamped, the work feeder 5 moves up at the timing of b2 and then moves to the right again at the timing of a1 to load a new work between the dies of the press 1 and at the same time move the finished work to the right. Carry out.

The relationship between the crank angle of the press 1 and the position of the feeder mechanism described in FIG. 3 will be described in more detail with reference to FIG. 4. In FIG. 4, the curve d indicates the crank angle of the press, and 0 ° is the upper side. The bottom dead center is 180 degrees, and the upper die 2 is driven to the bottom at the bottom dead center, and a force is applied to the work to process it. A curve a shows the movement of the work feeder 5 feeding the work, a-1 shows the forward movement of the work feeder 5, and a-2 shows the movement of the feeder in the return direction. The curve b shows the vertical movement of the work feeder 5, and the curve b-1 shows the downward movement. That is, the mechanical hand that clamps the work just before the work feeder 5 moves forward to reach a predetermined position (the uppermost portion in the curve a-1) and starts to descend just before reaching the lowest point is the curve c-. As shown in FIG. 1, the work is unclamped and the work is mounted on the work feeder 5. At the moment when the mechanical hand is unclamped and the work is placed on the lower die 3, the work feeder 5 is curved a-
As shown in Fig. 2, the return movement starts, and when it returns to an appropriate position that does not interfere with the press 1, the press 1 crank angle 180
When the workpiece reaches the bottom dead center, the machining operation is performed on the work. When the machining is completed and the upper die 2 of the press 1 starts to rise and rises to a position where it does not interfere with the work feeder 5, the curve c
Clamping operation starts as indicated by -2, and a plurality of mechanical hands are attached to the work feeder 5 at a feed distance as shown in Fig. 3a. Clamps the workpiece that has been machined, and returns to the mechanical hand that previously fed the workpiece to clamp the workpiece to be machined next. At the moment when the work is clamped, the work feeder 5 moves upward as shown by the curve b-2, and when the work rises to a position where it does not interfere with the mold, the work feeder 5 starts moving forward again as shown by the curve a-3. At the position where the crank angle of the press 1 is 360 degrees, the beginning of the present invention, that is, the crank angle of 0 degrees is achieved.

The curves a, b, and c are set in correspondence with the crank angle so that the work feeder 5 holds the work and performs high-speed motion, so that the curves are appropriate curves so that unnecessary acceleration is not applied. It corresponds to each timing shown in the figure.

Next, a circuit for controlling the above operation will be described with reference to FIG.

In FIG. 5, reference numeral 12 is a synchro oscillator 12 attached to the crank rotation shaft of the press 1 and capable of measuring the rotation angle of the crank absolutely, and 13 is for converting the angle signal from the synchro oscillator 12 into a digital code. It is a conversion circuit. The measured crank angle value of the press 1 converted into a digital code is input to the control computer 11. The computer 11 corresponds to the input crank angle and the feed axis and the vertical axis are recorded in the storage device in advance. , Reads each position information of the clamp axis and creates a position command signal. Numeral 18 is a feeder synchro oscillator attached to each of the three moving axes of the feeder for position detection. In the figure, only one axis is shown and the other two axes are the same and are omitted. Synchro oscillator for feeder
The position information of, for example, the feed axis measured by 18 is converted into a digital code by a conversion circuit 19 for converting the angle signal from the feeder synchro oscillator 18 into a digital code, and is input to the control computer 11. The position information of the feed shaft input to the computer 11 is compared with the position command signal previously created to create a deviation signal, and the position of the feed shaft previously recorded in the storage device in correspondence with the crank angle. Similarly to the information, a speed command signal for the feeder shaft drive motor corresponding to the deviation signal, which is predetermined and recorded in the storage device, is created by a digital code and output. The speed command signal of the feeder shaft drive motor output from the computer 11 is converted into an analog signal by the digital-analog conversion circuit 14 and then amplified to an appropriate electric power by the servo amplifier 15 to drive the servo motor 16. The servo motor 16 drives the feed shaft and is mechanically coupled to the tacho generator.
The rotation number of the servo motor is measured by 17, and the measured value of the rotation number is returned to the servo amplifier 15 to form a feedback loop to perform stable motor rotation control. As described above, the synchro oscillator 18 for detecting the position information of the feed axis is coupled to the feed axis driven by the servo motor 16, and the correct current position of the feed axis is measured and input to the control computer. Therefore, the work feeder 5 can be controlled according to the crank angle of the press according to the predetermined conditions.

Reference numeral 20 is a rotary cam switch attached to a coupling mechanism of a system different from the above-mentioned synchro oscillator 12 in the rotation mechanism of the crankshaft.The rotary cam switch 20 is a crank set in advance in hardware in association with crank rotation. The rotary cam switch 20 is operated at a predetermined angle or between predetermined angles to output an ON or OFF contact signal.

Therefore, the rotary cam switch 20 transmits a contact signal to the computer 11 at a predetermined position of at least one crank angle. In the computer 11, the signal from the sync transmitter 12 and the rotary cam switch are always
When the crank angle indicated by the synchro oscillator 12 and the crank angle indicated by the rotary cam switch 20 are different, the computer 11 issues an alarm as a system abnormality and operates the work feeder 5 by comparing the signals from the 20. Stop.

For example, if the operation timing is shifted near the timing to start the lift, the timing to start the feed, etc., the rotary cam switch 20 is operated at the crank angle corresponding to the dangerous timing, and the rotary cam switch 20 is operated. However, the predetermined press angle signal does not come back from the synchro oscillator 12 or the predetermined press angle signal comes back from the synchro oscillator 12 but the rotary cam switch 20 is not operating. Send an alarm.

Further, not only the dangerous timing as described above, but also a predetermined range of the crank angle, for example, 0 ° to 15 °, 15 ° to 3 °
It is possible to perform a contact signal at an appropriate time such as 0 ° and always check so as to issue an alarm even when the press angle signal does not return to the computer 11 as predetermined.

In the above description, the movement of the work feeder 5 is shown as a linear movement of three axes, but for the purpose of this purpose, the work feeder 5 having any movement may be used, and the crank angle sensor may be a synchro transmitter and a rotary cam. Although the switch 20 has been described, any sensor such as an absolute encoder may be used as long as it can detect the crank angle with the accuracy required by the system.

Further, although it has been described that the operation of the work feeder is stopped when an abnormality occurs, the operation of the press machine itself is stopped when necessary, so that the safety of the system can be more surely measured.

[Effects of the Invention] As described above, according to the present invention, a work to be machined by the press machine by moving in a three-dimensional direction corresponding to the crank rotation angle of the press machine is automatically determined on the press machine. In the work feeder that carries in and out to the processing position, the crank angle detection mechanism of the two-system press machine is provided, and the operation of the work feeder is stopped when a deviation occurs in the crank angle detection machine detection angle of the two systems. Therefore, even if an error occurs in the crank angle detection mechanism, it is possible to obtain an excellent effect of preventing the press machine and the work feeder from interfering with each other.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a press machine and a feeder device according to an embodiment of the present invention. FIG. 2 is a configuration diagram of a press machine and a feeder device according to an embodiment of the present invention. FIG. 3 is an explanatory view of the operation of the feeder device according to the embodiment of the present invention. FIG. 4 is a detailed explanatory view of the operation of the feeder device according to the embodiment of the present invention. FIG. 5 is a block diagram of a feeder control device according to an embodiment of the present invention. FIG. 6 is a block diagram of a conventional feeder control device. 1 ... Press 2 ... Upper mold 3 ... Lower mold 4 ... Crank angle meter 5,5-b, ... Work feeder 3 6,6-b ... Cylinder 7,7-b ... Cylinder 8 ...... Driver 9 …… Driver 10-1 …… Iron hand 10-2 …… Iron hand 10-3 …… Iron hand 11 …… Computer 12 …… Synchro oscillator 13 …… Conversion circuit 14 …… Digital analog Conversion circuit 15 …… Servo amplifier 16 …… Servo motor 17 …… Tacho generator 18 …… Feeder synchro oscillator 19 …… Conversion circuit 20 …… Rotary cam switch 31 …… Computer 32, 38 …… Sync oscillator 33, 39 …… Conversion circuit 34 …… Digital-analog conversion circuit 35 …… Servo amplifier 36 …… Servo motor 37 …… Tacho generator

Claims (1)

[Claims] 1. Corresponding to the crank rotation angle of a press machine,
In an automatic press working system including a work feeder that moves in a three-dimensional direction and automatically carries a work to be processed by a press machine into and out of a predetermined processing position on the press machine, a crank angle detection mechanism of two systems of the press machine. The crank angle detection mechanism of one system detects the crank angle for controlling the loading / unloading device that carries in / out the work feeder, and the crank angle detection mechanism of another system controls the work feeder itself. For detecting the crank angle for the purpose of operating the work feeder at least when there is a predetermined amount of deviation between the angle signal from the crank angle detecting mechanism of one system and the angle signal from the crank angle detecting mechanism of another system. A work feeder control device comprising: a control device for stopping the work feeder.