JPH0291707A - Pulse generator for positioning control - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a programmable pulse generator for controlling a positioning servo system.

[Conventional technology]

As an example of an arm movement diagram during the origin return operation by a conventional positioning control pulse generator of this type, the one illustrated in FIG. Are known.

In Fig. 5, 1 is an arm, 2 is a motor, 3 is a positioning device that drives and controls the motor, 4 is a limit switch (LS) for finding the origin, and 5 and 6 are limit switches (LS) for overrun prevention. Dovetail 5 is for the lower limit position, and 6 is for the upper limit position. Further, P1 to PN are a plurality of set stop positions for the arm 1.

Next, in FIG. 6, P is the starting position of the arm at the start of the return-to-origin operation, and Po is the position origin on the positioning control. During the return-to-origin operation, which is performed prior to normal control when positioning control is started by power-on, etc., the arm 1 is driven from its starting position P toward the lower limit switch 5 at a predetermined speed, and After passing the limit switch 4 for finding the origin, the drive motor 2 of the arm 1 is further decelerated by a specified distance between the limit switch 4 and the position origin 20 by controlling the total amount of drive pulses from the positioning device 3, and returns to the position origin. It is automatically stopped at P0.

[Problem to be solved by the invention]

However, in the home return control using the conventional method as described above, when the arm starting position P is located between the limit switches 4 and 5 on the arm transition path as described above, the position of the limit switch 4 is used as the starting point. Depending on the motor drive pulse total amount control, the position origin P
0 cannot be specified, and after the arm is stopped by the lower limit switch 5, the arm is switched to the limit switch 4.
It is necessary to perform a reversal transition to between the limit switch 4 and the upper limit switch 6, and then return to the origin return control starting from the limit switch 4, and these reversal transition operations have been handled manually or by an external automatic sequence.

In view of the above, the present invention automatically moves the starting point P to the position origin P, no matter where the starting point P is on the arm transition path.
It is an object of the present invention to provide a programmable pulse generator for positioning control that enables return to zero.

[Means to solve the problem]

In order to achieve the above object, the positioning control pulse generator of the present invention includes a setting device for setting a plurality of stop position data, etc., and a command pulse output circuit for a positioning device that drives and controls a load to be transferred. In a pulse generator for positioning control of a servo system control device, the return operation to the control position origin prior to the start of position control of the load is defined by a lower limit switch for overrun prevention, the position origin, and the origin. On the transfer path of the drive arm of the positioning device in which the origin finding limit switch and the overrun prevention upper limit switch are arranged in the stated order, the arm is moved in the direction of the lower limit switch. The arm is driven at a predetermined speed, and when the arm passes the position of the limit switch for finding the origin, the arm is further decelerated by a predetermined distance by controlling the total amount of drive pulses to the arm drive motor to reach the origin at the position. a first automatic return mode for stopping;
If the arm reaches the lower limit switch position without passing through the origin finding limit switch position, the driving direction of the arm is reversed at the lower limit position and the arm returns to the origin position. A second automatic return mode is provided in which the arm is moved to the position of the limit switch for extension, and the arm driving direction is reversed again after passing through the position, and thereafter the transition is controlled in the same manner as the first automatic return mode. It performs origin return control.

[Effect]

The origin return control in the positioning device as described above starts from the position of the origin finding limit switch provided at a specific distance from the position origin, and the transition direction is the direction to the position origin, and the The total amount of drive pulses required to shift the distance between the position origin and the limit switch position for origin search, that is, the number of origin shift pulses, is applied to the arm drive motor for which the arm shift distance is specified. The first automatic return mode is based on the above-mentioned first automatic return mode in which position control is performed by regulating the total amount of pulses added.

Therefore, automatic home return is always possible by programming the arm transition path so that the arm passes through the home position limit switch position regardless of the position of the starting point of the arm at the time of starting the home return control. Become.

In the present invention, when the arm starting point position is between the origin finding limit switch position and the overrun prevention upper limit switch position, the invention enters the origin return operation in the first automatic return mode; Furthermore, if the arm starting point position is between the origin finding limit switch position and the overrun prevention upper limit switch position, the arm is once brought to the lower limit switch position and then the driving direction is adjusted. An automatic return program that performs reversal and passes through the position of the limit switch for home finding, then reverses the drive direction again, and thereafter performs home return operation in a second automatic return mode that follows the first automatic return mode. A positioning control pulse generator having a positioning control pulse generator comprising a memory processing circuit comprising a CPU, etc., which receives each of the position signals as input, and enables automatic return of the arm to its origin regardless of its starting point position. It is.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a system configuration diagram of a servo system showing an embodiment of the present invention, FIG. 2 is a block circuit diagram of the pulse generator in FIG. 1, and FIG. 3 is an operation diagram of the positioning device drive arm.
FIG. 4 is a flowchart of positioning control corresponding to FIG. 3.

In FIG. 1, 2 is a motor for driving the arm 1; 3 is a motor for driving the arm 1;
7 is a positioning device for drive control of the motor, and 7 is a pulse generator for outputting command pulses to the positioning device.

In the block circuit diagram of FIG. 2, reference numeral 8 denotes an operation display, which is composed of a setting device 8a for setting the stop position, etc., and a display device 8b for displaying the contents. 10 is an arithmetic control circuit such as a CPU, 11 is a storage circuit for various data, 12 is a pulse output circuit for command pulses to the positioning device 3, 13 is an external signal receiving circuit, and 9 is a circuit for input/output signals of each of the circuits. It is a common bus.

Note that the illustrated signal ORG is an operating signal of the limit switch 4 for finding the origin, and iLt and it! are operating signals for the lower and upper limit switches 5 and 6 for overrun prevention, respectively.

The arm operation diagram shown in FIG. 3 will be explained below in correspondence with each control stage of 5TEPI to 5TEP 10 shown in the flowchart of FIG. 4. The origin return process shown in FIG. 4 is started by an external origin return command, and first the 5RE
At P1, pulses having a frequency corresponding to the moving direction and moving speed set by the setting device 8a are continuously output from the pulse output circuit 12 to the positioning device 3.

5TEP2 is a judgment processing step for determining whether or not the arm 1 has passed the position of the origin finding limit switch 4 (signal ORG: ON), and if it has passed (Yes),
Next, in 5TEP3, the moving speed of the arm 1 is reduced, and pulses are transmitted for the number of origin shift pulses corresponding to the position movement amount set in the setting device 8a.
When the pulse transmission is completed (STEP 4), the required return to origin is successfully completed. 5TEP of 0 or more 1 to 5TE
The progress to P4 is the operation shown in FIG. 3(a).

Moreover, if the arm 1 does not pass the position of the limit switch 4 (STEP 2: No, signal 0RGiOFF>> reaches the overrun prevention lower limit switch 5 first) (STEP 5: Yes, signal iLl: oN)
, the moving direction of the arm 1 is reversed from the direction at the 5TEPI (STEP 6), and the arm 1 is moved in the direction of the limit switch 4. If the limit switch 4 does not operate in this state and the overrun prevention upper limit switch 6 operates (S
TEP7: Yes, signal IL! :ON) The pulse transmission is stopped as the return-to-origin operation is abnormal. (STE
PIO).

Above 5TEP 1→5TEP 2→5TEP5~5T
The progress from EP7 to 5TEP1.0 becomes the operation shown in FIG. 3 (c).

Furthermore, if the limit switch 4 is passed before reaching the limit switch 6 during the 5TEP7 (STEP7: No → 5TEP8: Yes, signal OR
G: 0N-=STEP9: Yes.

Signal ORG: 0FF) The origin return operation is performed at the 5T
Return to EPI and perform the operation shown in Figure 3 (a) again. This operating state is shown in FIG. 3 (b).

By controlling the return to the origin of the arm 1 using the operation program as described above, the starting point P of the arm 1 at the time when the return to origin control is started.

Automatic home return control is possible regardless of the position of the

〔Effect of the invention〕

According to the present invention, in a control pulse generator for a positioning servo system, the return operation of the load drive arm to the position origin prior to the normal operation of the servo system is regulated by controlling the total amount of drive pulses to the arm drive motor. By providing a program that automatically moves the arm to the position of the limit switch for originating, which is the starting point of the section where the distance transition control is performed, it is possible to determine the starting point position of the arm at the start of the originating operation. Regardless of the situation, the arm can be automatically and reliably returned to its origin.

[Brief Description of the Drawings] Fig. 1 is a system configuration diagram of a servo system showing an embodiment of the present invention, Fig. 2 is a block circuit diagram of the pulse generator in Fig. 1, and Fig. 3 is a block circuit diagram of the pulse generator shown in Fig. 1. FIG. 4 is a flowchart of the pulse generator shown in FIG. 2, FIG. 5 is a configuration diagram of the conveyance device, and FIG. 6 is a diagram of arm operation according to the prior art. DESCRIPTION OF SYMBOLS 1... Arm, 2... Motor, 3... Positioning device, 4... Limit switch for origin search, 5... Lower limit switch for overrun prevention, 6... Upper limit switch, 7... Pulse generator, 8...
Operation display, 8a... Setting device, 8b... Display, 9
...Common bus, 10...Arithmetic control circuit, 11...
Memory circuit, 12... Pulse output circuit, 13... External signal receiving circuit, P3... Arm starting position, Po...
position origin. iyJ Figure 2 Figure 3 Figure Figure Figure

Claims (1)

[Claims] 1) In a pulse generator for positioning control of a servo system control device, which includes a setting device for setting a plurality of stop position data, etc., and a command pulse output circuit for a positioning device that drives and controls a load to be transferred, the load Regarding the return operation to the control position origin prior to the start of position control, a lower limit switch for overrun prevention, a limit switch for originating at a specified distance from the position origin, and an upper limit switch for overrun prevention. and drive the arm at a predetermined speed in the direction of the lower limit switch on the transfer path of the drive arm of the positioning device arranged in the stated order, and the arm moves toward the origin finding limit switch. A first automatic return mode in which the arm passes through the position and then further decelerates by a predetermined distance by controlling the total amount of drive pulses to the arm drive motor and stops at the position origin; If the position of the lower limit switch is reached without passing through the position of the limit switch for starting, the driving direction of the arm is reversed at the lower limit position and the arm is moved to the position of the limit switch for originating. and a second automatic return mode in which the arm driving direction is reversed again after passing through the position, and thereafter the transition is controlled in the same manner as the first automatic return mode. vessel.