JPH03213282A - Brake controlling method for industrial robot - Google Patents

Abstract

PURPOSE:To avoid unnecessary power consumption as well as to prevent a servomotor from being overheated, by applying a brake and demagnetizing the motor if the next traveling command is not given, and a standby command is given the other way at a time when the travel motion of a robot is stopped. CONSTITUTION:When the next travel command is not given after operation comes to a stop, whether a standby command is entered or not is judged, and when it is entered, a brake is applied by a command out of a central processing unit 11 via an input-output unit 16, and a power source for a servo amplifier 30 is cut, thus excitation to the motor is released. Then, waiting till the next travel command is emitted. In brief, waiting till the next jogging command, a program restarting command, an input signal out of peripheral equipment or the like so far standby are inputted or timer standby is over. After that, when the travel command is given the power supply is connected to the servo amplifier 30, exciting the servomotor, and operation of a braking device is released, then the brake is released, thereby restarting the operation.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a brake control method for an industrial robot [Prior art] In an industrial robot, the brake is released during program execution and the operating state is maintained. However, after the program execution is finished and a predetermined period of time has elapsed, the brake is applied and the servo power is turned off.

Further, during jog operation, when the jog switch is turned on, the brake is released, the servo power source is connected, the jog operation is performed, and after the end of the jog operation, the brake is applied and the servo power source is disconnected.

In the conventional brake control method described above, the brake is always released and the servo motor remains energized during program execution.

Therefore, when there is no movement command for a long time due to timer wait operation or interlock signal wait during program execution, in other words, when one operation ends and the next operation starts after the time set in the timer has elapsed. Even in cases where the robot waits for an external signal to be manually applied before starting the next operation, the position and posture of the robot are maintained electrically by continuing to excite the servo motors. .

[Problem to be solved by the invention]

There is no problem if such a standby time is very short, but such a standby time may continue for a long time in order to wait for peripheral devices to finish their operations or to avoid interference.

If the standby time becomes long, the servo motor is in an excited state, which consumes unnecessary power, and if the load applied to the servo motor is large, it may cause overheating of the motor.

As a solution to these problems, Japanese Patent Application Laid-Open No. 12228
There is also a method proposed in 77, but the brake does not operate until a predetermined time has elapsed, so during the elapse of the predetermined time,
Additionally, unnecessary power consumption and overheating of the motor occur.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a brake control method that can further reduce power consumption and overheating of the servo motor.

[Means to solve the problem]

According to the present invention, when the movement of the robot stops during execution of the robot program, the next movement command has not been issued.
If a standby command has been issued, the robot applies the brakes and de-energizes the motors that drive each axis of the robot.

In this state, if the next movement command is issued, the brakes are released and the motors that drive each axis of the robot are excited.

[For production]

With this method, when a program interrupt command is given manually, the robot's operation can be paused under predetermined conditions even while the program is running, by waiting for a human signal from a peripheral device, etc., or by waiting for a predetermined time on a timer. Then, the brake is applied and the servo motor is de-energized, so
There is no unnecessary power consumption and motor overheating can be prevented.

Then, when the operation of the robot is temporarily stopped and a primary movement command is generated, power is connected to the servo motor, the brake is released, and the robot starts operating.

Note that it operates in the same way during jog operation.

When the jog operation is completed and a predetermined condition is satisfied, the brake is applied and the servo motor is de-energized, and with the next jog operation command, the servo motor is energized, the brake is released, and the robot moves.

〔Example〕

FIG. 2 is a block diagram of an industrial robot that implements the brake control method of the present invention.

In the figure, 10 is a robot control device, 30 is a servo amplifier that drives a servo motor for each axis of the robot, 40 is a mechanical part of the robot, and 50 is a work target of the robot. The control device 10 has a central processing unit (hereinafter referred to as CPLJ) 11, and the CPU II includes a memory 12 consisting of a ROM,
Memory 13 consisting of RAM, teaching operation panel 14, operation panel 1
5, an I10 unit 16, an axis control circuit 17, and an interface circuit 19 for interfacing with an operating object are connected via a bus 20.

The memory 12 stores various control programs to be executed by the CPU II. The memo IJ 13 stores data such as teaching data inputted from the teaching operation panel 14, operation panel 34, etc., and setting values of various parameters. The teaching operation panel 14 includes a numerical display necessary for operating the robot,
It has a lamp and operation buttons. The operation panel 15 has various keys such as a numeric keypad and function keys, and inputs various data to the control device 10 from the outside.

In relation to the present invention, the I10 unit 16 is connected to a power switch of the servo amplifier 30 and a brake device (not shown) in the robot mechanism section 40, and as described later, commands to turn on and off the power of the servo amplifier 30. It is designed to output a signal, an on/off command signal for the brake device, and a command signal for validating/invalidating the on/off command signal for the servo amplifier 30 and the brake device.

The axis controller 17 includes a compensator that controls each axis of the robot, and a servo circuit 18 for each axis. It is connected to a servo motor (not shown) for each axis via a servo amplifier 30. The interface circuit 19 is connected to a work object 50 and peripheral equipment to provide an interface.

Note that the configuration of the robot described above is the same as that of a conventional robot, and detailed explanation will be omitted.

Next, the operation of this embodiment will be explained with reference to the flowchart of FIG.

First, when the robot is powered on, the CPU 1l operates the brake device via the I10 unit 16,
Apply the brake (Sl), turn off the power to the servo amplifier 30, and release the excitation to the servo motor (S2).

Next, whether a jog operation command is manually input from the operation panel 5 or
Alternatively, a program execution command is input, and it is determined from the read program whether there is a movement command (S3).

When there is a jog operation command or a movement command from a program, the power supply of the servo amplifier 30 is connected, the servo motor is excited (S4), and the operation of the brake device is released to release the brake (S5), and the robot is driven.

When the robot starts moving, it is determined whether the robot has stopped moving (S6).

That is, if there is a jog operation command, it is determined whether the jog operation has been completed, or if there is a movement command by a program, it is determined whether the movement has been moved to the commanded position and stopped, and YES is determined.
If so, proceed to S7.

In S7, it is determined whether a movement command has been issued, and if NO, the process advances to S8, and if YES, the process returns to S6.

In S8, it is determined whether or not a standby command has been issued, and if YES, the process returns to Sl, applies the brake, and turns off the servo power (S2). If NO, the process returns to S7.

This movement stop includes stopping when the jog operation ends during jog operation, stopping when the program ends, stopping when a program interrupt command is input from an external device or manually, and waiting for a human input signal from a peripheral device or the work target while the program is running. There are stoppages due to waiting for a human power signal to perform the next operation, or stoppages due to waiting for a timer to stop operation for a predetermined time, and after the operation has stopped due to these matters,
If the next movement command does not occur (when there is no jog operation command, program restart command, or human signal from a peripheral device that allows the next operation, or when timer standby is not released), is a standby command received? Decide whether or not
If the signal has been received, the process returns to step S1, applies the brake, and de-energizes the servo motor. Then, it waits until the next movement command is issued (step 33).

That is, it waits until the next jog operation command, program restart command, human power signal from a waiting peripheral device, etc. is received, or until the timer standby ends. When the next movement command is issued, the servo amplifier 30 is connected to a power source, the servo motor is excited, the brake device is released, the brake is released, the operation is resumed, and the same process as described above is repeated.

〔Effect of the invention〕

As described above, in the present invention, when the movement of the robot stops during program execution, if the next movement command has not been issued and a standby command has been issued, the brakes are applied and the motors are stopped. Since the excitation is removed, unnecessary power consumption can be avoided and overheating of the servo motor can also be prevented.

[Brief explanation of drawings]

FIG. 1 is an operational processing flowchart of an embodiment of the present invention;
FIG. 2 is a block diagram of an industrial robot according to an embodiment of the present invention. lO...control device, 11...central processing unit (cpu
>. 20...Bus. Figure 1 Procedural amendment (method) Engraving of the drawing Figure 2 May 11, 1990 1. Indication of the incident 1990 Patent Application No. 8828 2. Name of invention Brake control method for industrial robots 3. Amendment Relationship with the case involving a person who does
, Date of amendment order (starting gate) April 24, 1990 5゜Drawing subject to amendment 6゜Contents of amendment

Claims (2)

[Claims] (1) In a brake control method for an industrial robot, when the movement of the robot stops during execution of a robot program, if the next movement command has not been issued and a standby command has been issued, the brakes are applied; A brake control method for an industrial robot characterized by releasing the excitation of a motor that drives each axis of the robot. (2) In a brake control method for an industrial robot, when the movement of the robot stops during execution of a robot program, if the next movement command has not been issued and a standby command has been issued, the brakes are applied; A brake for an industrial robot characterized in that the motors driving each axis of the robot are de-energized, and when the next movement command is issued, the brake is released and the motors driving each axis of the robot are excited. Control method.