JPH03292509A - Industrial robot - Google Patents

Abstract

PURPOSE:To simplify a remote teaching operation by providing a ball partly protruding to a robot teaching device in such a way that the ball is freely rotatably in an optional direction at that position, taking the rotations of two directions orthogonal to each other out of the ball, and outputting the pulses at the same time in response to the rotations of the ball. CONSTITUTION:A worker moves a ball 20a of a teaching device 16 in an optional direction on a plane. Thus the rotational frequencies of the ball 20a are taken out at the same time in two directions orthogonal to each other. The pulses are produced by a pulse generator 20c in accordance with the preceding rotational frequencies. Thus a controller 7 drives each motor in response to the number of pulses and the forward/reverse directions of these pulses. As a result, the worker can move the tip part of the device 16 and a working tool fixed at the tip part in the turning direction of the ball 20a just by looking at the working tool. Then the worker can easily teach a robot the working position of the working tool without turning away one's own eyes from the working tool.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to the insertion and removal of parts in high-mix low-volume production.
The present invention relates to a versatile industrial robot used for assembly, etc., and particularly to a teaching device for teaching the working position of a working tool attached to a moving part at the tip of the robot.

[Prior Art] Recently, the use of industrial robots, which are highly versatile for inserting, extracting, assembling parts, etc. in high-mix, low-volume production, has been increasing. There are various types of industrial robots used for this type of work, such as Cartesian coordinate robots and articulated robots, but all robots have a moving part that moves on a horizontal or vertical plane under the rotation of two motors. A working tool for performing a predetermined work is attached to the moving part.

Further, this robot has a control device that drives the motor, and this control device drives the motor to move the work tool attached to the moving part to a predetermined work position on a plane, and The work tools are configured to be driven in accordance with the order to complete a predetermined work. Furthermore, a teaching device for teaching the working position of the working tool is connected to this control device. As shown in FIG. 4, this teaching device 16 includes a teaching command unit 17 that outputs a teaching command signal for selecting a teaching mode, a teaching completion command unit 18 that outputs a teaching completion signal, and a current position of each motor (not shown). It has an entry section 19 that outputs an entry signal for storing the information, and a movement command section 20 consisting of keys indicating four directions of movement of a work tool (not shown).When the teaching mode is selected, the movement command section 20 When the amount of movement of each motor is commanded, each motor is driven to move the power tool to a desired position, and the current position of each motor is stored as a working position after waiting for an entry signal. There is.

[Problems to be Solved by the Invention] In this teaching device 16, when the key of the movement command unit 20 is pressed after the teaching mode is selected,
A pulse is output to a control device F (not shown), and each time the control device receives this pulse, it changes the target position of each motor, drives the motor so that the motor moves to this target position, and controls one working tool. is driven in the direction indicated by the key. Therefore, in this teaching device 16, in order to move the work tool by pressing each key, when changing keys, as the work tool approaches the desired work position, the key to be pressed and the tip of the work tool are alternately pressed. This has disadvantages such as having to keep an eye on it, which is extremely troublesome.

The present invention aims to eliminate the above-mentioned drawbacks, and provides a robot teaching device configured to easily teach the working position of a work tool without turning away from the work tool. It is something.

[Means for solving the problem] In order to solve the above problem, a robot having a moving part that moves on a plane by receiving rotation of two motors is arranged, and this moving part has a task of performing a predetermined work. Tools are installed. The robot also has a control device that controls a motor to move the moving section and the work tool to a predetermined work position. The control device is configured to sequentially recall predetermined working positions, move the working tools to the positions, and operate the working tools according to a predetermined sequence. Further, a teaching device for teaching the working position of the working tool is connected to this control device. In this teaching device, a partially exposed ball is held at that position so that it can rotate freely in any direction.
Moreover, two pulse generators are installed so as to extract the rotation of the ball in two orthogonal directions. Further, the control device is configured to drive two motors in response to pulses transmitted from the pulse generator when the teaching mode is selected, and the teaching device can move the power tool together with the moving section. It is configured as follows.

In addition, if a motor that controls the posture of the work tool or a motor that controls its elevation is attached, the teaching device should be provided with multiple movement axis selection keys so that when the teaching mode is selected, the movement axis The control device may be configured to drive the motor corresponding to the axis selection key using pulses from the pulse generator only when the selection key is selected.

[Operation] In the above industrial robot, when the teaching mode is selected by the teaching device, the control device waits for a pulse from the teaching device. In this state, the operator can move the ball of the teaching device in any direction on the plane. When the ball is moved, rotational speeds in two orthogonal directions are simultaneously obtained due to the rotation of the ball, and pulses are transmitted from the pulse generators in accordance with the rotational speeds. When these pulses are transmitted, the control device drives each motor according to the number of pulses and their forward and reverse directions.

Therefore, even if the operator only looks at the work tool and does not look at the teaching device, the tip and the work tool fixed to it can move in the direction of the rotation of the ball, and the work tool can be moved freely. When the position is reached, the current position of each motor can be stored as a working position by waiting for an entry signal.

In addition, since the motor is driven by pulses from the pulse generator only when the movement axis selection key is pressed, the power tool may move against the operator's intention and its position may be incorrectly taught. Nothing will happen.

Furthermore, by similarly selecting the movement axis selection key to select a desired motor and driving it, the attitude and height position of the power tool can be taught as desired.

[Examples] Examples will be described below based on the drawings. In FIGS. 1 and 2, reference numeral 1 denotes an articulated robot, which is an example of an industrial robot, and includes a first arm 2 and its tip that rotates on a horizontal plane under rotation of a first motor (not shown). It has a second arm 3 which pivots on a horizontal plane in response to rotation of a second motor (not shown). The tip of the second arm 3 constitutes a moving part of the robot 1, and a working tool 4 is attached to this moving part, and is configured to move on the XY plane by driving each motor. .

The robot 1 has a control device 7 that controls a first motor, a second motor, and a working tool 4. This control device 7 includes a control section 8 consisting of a microcomputer, a storage section 9 that stores various information for driving the robot l such as work positions, an operation section 10 that sends various operation command signals such as a work start signal, and various data. It has a display section 11 for displaying information. The control unit 8 also includes a first motor drive command unit 12 and a second motor drive command unit 13.
Motor drive command section 12 and second motor drive command section 13
are connected to a first motor drive section 14 and a second motor drive section 15 that supply power to the first motor and the second motor, respectively, and when a target movement amount is given from the control section 8,
A drive command signal corresponding to this is sent to each motor drive unit 14.15.
It is configured to send to. Each of the motor drive units 14
．． 15 is configured to, upon receiving a drive command signal, supply power to each motor in response to the drive command signal to move each motor a predetermined distance at a predetermined speed. Further, the amount of movement of each motor is detected by an encoder (not shown) and is configured to be fed back to the control section 8.

A teaching device 16 for teaching the working position of the working tool 4 is attached to the operating section 10 of the control device 7,
The operation unit 10 is configured to send various signals from the teaching device 16 to the control unit 8 when a teaching mode is selected by the teaching device 16. This teaching device 16 includes a teaching command section 1 that outputs a teaching command signal for selecting a teaching mode.
7. It has a teaching completion command section 18 that outputs a teaching completion signal and an entry section 19 that outputs an entry signal that stores the current position of the motor. Further, in this teaching device 16, a ball 20a with a portion exposed on the upper surface as a movement command unit is held at that position so as to be rotatable in any direction, and a ball 20a is in contact with the ball 20a in two directions perpendicular to the ball 20a. A roller shaft 20b having a roller portion for taking out the rotation is rotatably held. A pulse generator 20c is connected to one end of the roller shaft 20b, and is configured to obtain rotational speeds in two orthogonal directions simultaneously and at a ratio corresponding to the direction of rotation. This pulse generator 20c includes a slit disk 20d fixed to one end of the roller shaft 20b, and a slit disk 20d fixed to one end of the roller shaft 20b.
It has two sensors 20e arranged to detect pulses obtained by the roller shaft 2 with a predetermined phase difference.
The rotation speed of 0b and its forward and reverse rotation directions can be detected.

Additionally, two Z-axis and θ-axis motors (not shown) control the height position of the work tool 4 and its posture.
There are selection keys (xy, z,
A moving axis selection key 21 consisting of θ) is provided, and a motor corresponding to a key signal output from the moving axis selection key 21 is driven.

As shown in FIG. 3, the control section 8 of the control device 7 performs the following: 1) Determines whether or not a teaching command signal is being output, and jumps to step 8) when a teaching signal is being output.

2) Determine whether there is a work start signal, and if there is no work start signal, return to 1).

3) Storage unit 9 as coordinate data consisting of the rotation angle of each motor.
The work position stored in advance is recalled and this is set as the target position.

4) Calculate the target movement amount from the difference between the target position and the current position and send it to each motor drive command section 12.13.

5) Wait for the positioning completion signal to be output.

6) Send a drive command signal to the working tool 4, wait for a work completion signal from the working tool 4, and determine whether or not the cycle is at the end. If the cycle is not at the end, return to step 3).

7) At the end of the cycle, return to 1).

8) Determine whether or not there is a key signal from the moving axis selection key 21, and if there is no key signal, jump to 15).

9) The number of pulses input from the teaching device 16 is measured for a predetermined period of time according to the key signal.

10) Add the measured number of pulses to the previous target command value to calculate a new target command value.

11) Convert the target command value into coordinate data consisting of the rotation angle of each motor, and calculate the target movement amount of each motor from the difference from the current position of each motor.

12) Send the target movement amount of each motor to the respective motor drive command section 12.13.

13) Determine whether or not there is an entry signal, and if there is no entry signal, jump to 15).

14) Store the current position of each motor in the storage unit 9.

(Increments the address of the storage unit 9) 15) Determine whether or not there is a teaching completion signal, and if the teaching completion signal is not output, return to 8).

16) When the teaching completion signal is output, 1)
Return to

It is configured to perform the above operations.

In the above robot, when teaching the working position of the work tool 4 on the XY plane from the teaching device 16, a teaching command signal is output from the teaching command section 17,
When the teaching mode is selected, the movement axis selection key 21 (XY) is pressed to select the plane on which the work position is to be taught. At the same time, the control device 7
Pulse generators 2 for each of the X-axis and Y-axis on the plane of
Start measuring pulses transmitted from 0c for a predetermined period of time. In this state, the operator holds the ball 20 of the teaching device 16.
When α is rotated in any direction on the XY plane, the two roller shafts 20b rotate at a ratio corresponding to the direction, and pulses are transmitted from each pulse generator 20c. When a predetermined period of time has elapsed, the number of pulses transmitted during this period is added to the previous target command value of the corresponding motor to calculate a new target command value. This target command value is converted into coordinate data consisting of the rotation angle of each motor, and the target position is calculated. The target movement amount of each motor is calculated from this target position and the current position of the motor, and this is calculated from each motor drive command unit 12.
．． 13. Therefore, the motor drive unit 14, 1
5, each motor rotates at a predetermined speed and a predetermined distance, thereby moving the working tool 4 at the tip of the second arm 3. At the same time, the presence or absence of an entry signal from the teaching device 16 is determined.
6, write pulse generator 2 again.
The number of pulses from 0c is measured for a predetermined period of time, and the above operation is repeated.

When the entry signal is output from the teaching device 16, the current position of each motor is stored in the storage section 9, and the presence or absence of a teaching completion signal from the teaching device 16 is determined. Teaching equipment 31
When the teaching completion signal is not output from 16,
Prepare for teaching the next work position. Further, when the teaching completion signal is output from the teaching device 16, preparation is made for the work start signal.

When a work start signal is input from the operation unit 10, predetermined work positions are sequentially called, the robot l starts a predetermined operation, the work tool 4 performs a predetermined work at a predetermined work position, and one cycle is completed. Complete the work.

Further, when a key signal for selecting a motor for controlling the posture of the work tool 4 or a motor for controlling the height position of the power tool 4 is output from the movement axis selection key 21, any pulse from the pulse generator 20c is used. The motor drive command section and motor drive section of the motor corresponding to the key signal are driven, and the motor can move by a predetermined amount to obtain an arbitrary posture or an arbitrary height position.

Although the embodiment is limited to teaching the working position on the horizontal plane, the same effect can be obtained when teaching the working position on the vertical plane. Furthermore, although the embodiment describes an articulated robot, the same effect can be achieved with a Cartesian coordinate robot. In this case, there is no need to convert the pulses sent from the teaching device into coordinate data consisting of the rotation angle of each motor, and the pulses can be directly used as the target movement amount, resulting in simple control.

[Effects of the Invention] As explained above, the present invention arranges a ball with a portion of it protruding in a teaching device of a robot so that it can rotate freely in any direction at that position, and rotates the ball in two orthogonal directions. Since the teaching device is configured to take out the ball and simultaneously output pulses according to its rotation, by rotating the ball of the teaching device in any direction, it is possible to output the number of pulses at a ratio corresponding to that direction. When teaching the working position of a work tool, you can teach in two directions on a plane by simply rotating the ball in any direction, without having to look only at the tip of the tool and at the teaching device. There are advantages such as being able to easily perform remote teaching without having to perform the troublesome work of watching the computer and the teaching device alternately. Furthermore, in the present invention, the motor is not driven unless the movement axis selection key is pressed, so there is no possibility that the work tool will be moved against the operator's intention and its position will be taught. be. Furthermore, the present invention can select a movement axis selection key to move a motor for controlling the posture of a power tool or a motor for controlling its height position, and can teach not only the posture of a power tool but also its height position. It has the advantage that it can also be used.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram illustrating the entirety of an articulated robot as an example of the present invention, FIG. 2 is a block diagram showing the configuration of a teaching device according to the present invention, and FIG. 3 is a diagram illustrating a control device according to the present invention. A flowchart showing the operation, and FIG. 4 is a block diagram showing the configuration of a conventional teaching device. 1 robot, 2 first arm, 3 second arm, 4 work tool, control device, 8
Control unit, storage unit, 10 operation unit, display unit, first motor drive command unit, second motor drive command unit, first motor drive unit, 15 second motor drive unit, teaching device, 17 teaching command unit, teaching completed Command section 19 Entry section, movement command section,
20a ball, roller axis, 20c pulse generator, slit disk, 20e sensor, movement axis selection key

Claims (1)

[Claims] 1) A work tool is attached to a moving part that moves on a plane under the rotation of two motors, and the motor is driven to move this work tool to a predetermined work position. In an industrial robot equipped with a control device configured to sequentially move objects to predetermined work positions and drive them in a predetermined order to complete a predetermined task, a teaching command signal is output to the control device. A teaching device equipped with a teaching command unit that outputs a teaching completion signal, a teaching completion command unit that outputs a teaching completion signal, and an entry unit that outputs an entry signal that stores the current position of each motor is connected, and a ball that is partially exposed to this teaching device is connected. is held at that position so as to be freely rotatable in any direction, and two pulse generators are installed so as to extract the rotation of the ball in two orthogonal directions. An industrial robot characterized in that it is configured to drive two motors according to pulses generated by the robot. 2) While two motors are provided to control the posture of the work tool and its elevation, the teaching device is provided with a plurality of movement axis selection keys, and the control device is set in the teaching mode and when the movement axis selection key is selected. Only when there are
2. The industrial robot according to claim 1, wherein the industrial robot is configured to drive a motor corresponding to a selection key in response to a pulse from a pulse generator.