JPH0523985A - Robot control system - Google Patents

Abstract

PURPOSE:To provide the above robot control system which is able to judge a work conveying interval according to the type of a work. CONSTITUTION:Each of works 1A, 1B is hung down from a hanger 2a of a conveyor 2 and conveyed, and a painting robot 3 performs paining operations by a signal out of a hanger detecting switch 19. The work 1A and the work 1B vary in size and form from each other, and the work 1A is hung down alternately, and the work 1B are hung down in every third place. When these works 1A, 1B are hung down from the hanger 2a, work conveying interval data are inputted into teaching data at each work by operation of a data setter 21, and these data are stored in a control unit 18 which reads the work conveying interval data together with the teaching data, overriding any detecting signal of the no work hanger, and prevents any possibility that the robot 3 operates to paint the no work hanger.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot control system, and more particularly to a robot control system configured to execute a taught work by a robot when a work conveyed by a conveyor arrives at a work area.

[0002]

2. Description of the Related Art For example, in a coating line for automatically painting a work conveyed by a conveyor using a painting robot, when the work arrives at a work area, a work switch detects a hanger in which the work is hung. A signal is output, and the painting robot starts the painting operation by using this detection signal as a start signal. Teaching data according to the shape of the work is stored in advance in the control device that controls the painting robot. When a signal from the detection switch is received, the control device reads the teaching data of the work and controls the operation of the robot.

The conveyor is provided with hangers at regular intervals, and the work is conveyed while being suspended from each hanger. However, depending on the type of the work, the work may be hung on every other hanger instead of hanging the work.

Therefore, if the coating robot starts the coating operation only by the signal from the detection switch, the coating robot will perform the coating work even if the hanger without the work arrives, and the coating material is wasted. become.

When a hanger with a work and a hanger without a work are conveyed as described above, conventionally, the presence or absence of the work is detected by using an optical sensor such as a photoelectric tube, and when the hanger without the work arrives, the detection switch is used. By ignoring the detection signal of, the coating robot does not perform coating work even on a hanger without a work.

Further, in the control device, the number of pulses output from the conveyor at the same time when the detection signal from the detection switch is output is counted, and the number of pulses of the work interval set when suspending the work on the hanger is compared. However, the detection signal from the detection switch output while the count value reaches the set number of pulses is ignored. As a result, even if a hanger without a work is detected by the detection switch, the detection signal is ignored so that the painting robot does not perform the painting operation on the hanger without a work.

[0007]

However, in the structure in which the presence or absence of the work is directly detected by using the photoelectric tube as in the above-described conventional method, the photoelectric tube must be provided at the entrance of the work area in addition to the hanger detection switch. Costs extra. Further, with such a configuration, there is a case where the work cannot be detected depending on the shape of the work, and there is a disadvantage that the painting work is not performed even though the work passes through the work area.

Further, in the system configured to ignore the next hanger detection until the constant number of pulses is counted after the hanger detection, it is not possible to cope with the hanger interval without the work being not constant. For example, in a coating line in which works of different types are conveyed, in the case of the work A, the work is hung from every other hanger depending on the work shape or size, but in the case of the work B larger than the work A, every other work is suspended. Will be hung on a hanger. In this way, if the interval without a work differs depending on the work, in the system configured to ignore the next hanger detection until the constant pulse number is counted after the hanger detection described above, only one pulse number to be ignored can be set. Therefore, for example, if the work A is hung on every other hanger and the hanger is set to ignore every other hanger, if the work B is hung on every other hanger, the pulse of the two hangers can be ignored. Therefore, there is a problem in that the coating operation is performed on the second empty hanger, it is not possible to handle a plurality of types of works, and it is not possible to accurately determine the presence or absence of a work.

Therefore, an object of the present invention is to provide a robot control system that solves the above problems.

[0010]

DISCLOSURE OF THE INVENTION The present invention comprises a conveyor on which hangers at predetermined intervals are hung, and a work which is hung on the hangers and has an interval of at least one hanger.
Hanger detection means for detecting the arrival of the hanger, based on the detection signal from the hanger detection means, a robot for performing work by playback data according to the type of the work, and suspended by the hanger of the conveyor Work transfer interval input means for inputting the number of hangers between works according to the type of transferred work, and the number of hangers between works input by the work transfer interval input means and the number of output signals of the hanger detection means match. Then, the control means controls the robot based on the playback data corresponding to the type of the work.

[0011]

By inputting the number of hangers between the works according to the kind of works by the work carrying interval input means, even if the hanger detection switch detects a hanger without a work, the detection signal is ignored and the next work is carried. It is possible to surely execute the work for the worked work.

[0012]

1 to 3 show a coating robot system to which an embodiment of a robot control system according to the present invention is applied. In each drawing, the coating robot system comprises a multi-joint type coating robot 3 disposed in the vicinity of a conveyor 2 to which a work 1 is conveyed. For example, one lot of 100 pieces of work 1 is continuously supplied to the coating line for each lot.

Further, the conveyor 2 has different kinds of works 1
A, 1B and the like are conveyed for each lot, and the coating robot 3 performs the coating operation based on the teaching data of the works 1A, 1B and the like. Since the workpieces 1A and 1B have different shapes and sizes, when suspending the hangers 2 provided on the conveyor 2 at regular intervals, for example, in the case of the workpiece 1A, the hangers are hung every other hanger. Case hanger 2
Make it hang every other time.

Therefore, the coating robot 3 coats the work 1 while the work 1A or 1B is suspended by the hanger 2a of the conveyor 2 and conveyed in the coating area. At the coating start position XA (coating area entrance) of the conveyor 2, a hanger detection switch 19 that comes into contact with the hanger 2a suspended from the conveyor 2 and outputs a detection signal is provided. The detection switch 19 may be a contact type switch as shown in FIG. 1 or an optical non-contact type sensor may be used.

Further, the conveyor 2 is provided with a pulse transmitter 20, and the pulse transmitter 20 outputs a number of pulses proportional to the conveying speed of the conveyor 2. Therefore, the painting robot 3 is controlled to perform the painting work on the work 1 in synchronization with the pulse output from the pulse transmitter 20.

When the detection signal from the detection switch 19 comes in, the control device 18 controls the operation of the coating robot 3 based on the teaching data stored in the work data table (hereinafter referred to as WD) as described later.

The workpieces conveyed by the conveyor 2 include workpieces 1A and 1B having different shapes as shown in FIG.
Since the workpieces 1A and 1B have different sizes and shapes,
As described above, the interval when hanging on the hanger 2a is different. The shape of each work 1A, 1B is not actually a simple shape as shown in FIG. 1, but is a simple shape for the sake of easy understanding. The types of the work 1 are not limited to the above two types, but there are many types in practice.

Reference numeral 21 denotes a data setting device (work transfer interval input means), which is provided in the vicinity of a mounting position for suspending the work 1 on the conveyor 2. This data setter 21 works 1
When the hangers are hung on the hanger 2a of the conveyor 2, the number of hangers between the works as the work transfer interval data is input, and the work data designating the type of each work 1 and the address of the WD table described later are also input. The data setting device 21 is installed at a position apart from the coating booth where the robot 3 is installed and is connected to the control device 18 via a signal cable. Then, by operating the data setting device 21, a program having teaching data is set in the control device 18.

As shown in FIG. 3, the data setter 21 includes a control unit (CPU) 21A and a keyboard 21.
B, transmission switch 21C, display 21D and the like. The display 21D displays the address and operation program stored in the WD table of the controller 18. Further, the control unit 21A performs data output to the display 21D and data communication with the control device 18 by input operation of the keyboard 21B and the transmission switch 21C.

Here, the coating robot 3 and the control device 18 for controlling it will be described.

In FIG. 2, a turning drive unit 5 is provided on the base 4 of the painting robot 3. A swivel base 6 is provided on the swivel drive unit 5 and rotates about an axis A fixed to the base 4. The bracket 6a on the swivel base 6 is provided with a column 7 that rotates in the front-rear direction about the axis B. In addition, the turning base 6
A column driving unit 8 is provided on the upper bracket 6a.

At the upper end of the column 7, an arm 9 is provided which is rotatable about the axis C in the vertical direction. An arm drive unit 10 is provided at a connecting portion between the arm 9 and the column 7. A wrist drive unit 11 is provided on the rear portion of the arm 9. Further, a wrist mechanism 12 is provided at the tip of the arm 9. The wrist mechanism 12 has cases 13 and 14 and a mounting shaft 15. The case 13 is configured to rotate in the vertical direction about the axis D. The case 14 is adapted to rotate in the left-right direction about the axis E. The mounting shaft 15 is a mounting portion of the coating gun 16, and is configured to rotate about an axis F orthogonal to the axis E of the case 14.

A controller 18 stores teaching data and counts the pulses from the pulse generator 20, and controls the operation of the coating robot 3 in conjunction with the conveyance of the work 1. Therefore, in the painting robot 3, each drive unit is driven by a command from the control device 18, and each movable unit such as the swivel base 6, the support column 7, the arm 9, and the wrist mechanism 12 operates.

Drive units 5, 8, 1 for driving the above movable units
0 and 11 are detectors (for example, resolvers) 5a, 8a, 10a, 1 for detecting the rotation angles (rotational positions) of the axes A to F.
1a to 11c are provided (however, the detector 5 in FIG.
a, 11a to 11c cannot be hidden).

In FIG. 3, the control device 18 controls the respective drive units so that the coating robot 3 configured as described above performs a predetermined coating operation based on the teaching data for the work inputted in advance. And the control circuit 1
8A includes a motor drive circuit 18B that outputs a drive signal to each drive unit of the painting robot 3 and a storage device (for example, a magnetic disk device) 18D that stores a WD table into which teaching data and the like are input. ..
Further, the motor drive circuit 18B includes the drive units 5, 8, 10,
It is connected to 11 detectors, and when each drive unit operates, a detection signal corresponding to the rotation angle of each axis A to F is fed back from each detector to the motor drive circuit 18B.

As will be described later, when the hanger detection switch 19 detects the hanger 2a of the conveyor 2, the control circuit 18A reads the teaching data of the next workpiece to be conveyed, which is stored in the storage device 18D. A coating control means 18E is provided which ignores the detection signal of the hanger without a work based on the set work transfer interval data and controls the coating robot 3 based on the teaching data when the next hanger with a work arrives. There is.

Reference numeral 23 is a coating gun control device, which is a control circuit 18
It is connected to A. The coating gun control device 23 controls the operation of the coating gun 16 in response to commands for each of the spray gun, static electricity on / off, paint discharge amount, and atomizing pressure operation modes.

The processing executed by the data setting device 21 and the control circuit 18A in the coating robot system having the above structure will be described below.

The operator operates the work 1 in FIG. 1 (for example, 1A to 1A).
At the mounting position where D) is hung on the hanger 2a of the conveyor 2,
Every time one work 1 is hung, the keyboard 21B of the data setter 21 is operated to set the work data of the work 1 and W.
Input the address of the D table 24 (see FIG. 4). As work data to be input by the keyboard 21B,
For example, as shown in FIG. 5, it is predetermined such as “1-A”, “1-B”, “1-1C”, and “1-D” according to the types of the works 1A to 1D.

Here, the operator transfers the work 1A to the conveyor 2
The work data “1-A” and the address “0” are input by the keyboard 21B of the data setting device 21 while being hung on the hanger 2a of the work set, and the work transfer interval data is provided as work transfer interval data for preventing malfunction of the hanger without the work. Enter "01", which represents the number of hanger 2a with no hanger.

First, the processing executed by the CPU 21A of the data setting device 21 will be described.

In FIG. 6, the CPU 21A first sets S1.
(The following steps will be omitted.) The operator specifies and reads the teaching data of the work based on the work data. Then, the read teaching data 25 (shown in FIG. 7) is displayed on the display 21D (S2).

Then, by operating the keyboard 21B, the number of hangers between the works as work transfer interval data is set to "0".
When "1" is input, this "01" is registered in the address 07 as shown in FIG. 7 (S3).

When the transmission switch 21C is pressed in the next S4, the teaching data 25 in which the work conveyance interval data shown in FIG. 7 is registered is transmitted to the control device 18 and written in the disk (storage medium) of the storage device 18D. Be done.

In this way, the hanger 2a of the conveyor 2
The teaching data in which the work transfer interval data is registered in the order of the works hung on is registered in the control device 18.

When the work hung on the hanger 2a is switched from the work 1A to the work 1B, every two hangers are provided, so that the work transfer interval data shows the number of hangers "02" between the works as shown in FIG. be registered.

Next, the processing executed by the control circuit 18A of the control device 18 will be described.

In the control circuit 18A, the processing shown in FIGS. 9 to 11 is performed. First, in the processing procedure at the time of coating operation, it is checked in S11 shown in FIG. 9 whether or not teaching data is input, and the teaching data is input. If there is a change in, the process proceeds to S12 and the work transfer interval data stored in the storage device 18D is set. However, if there is no teaching data input in S11, there is no change and S1
The process returns to S11 without executing 2. Therefore, for example, when the teaching data stored in the storage device 18D is changed once due to an input error by the operator, for example, when there is a change from the work A to the work B, the work transfer interval before the coating operation is performed. The data is updated from "01" to "02".

Further, the control circuit 18A has the same structure as in FIG.
When the hanger 2a is detected by the hanger detection switch 19 in S13 and the detection signal as the start signal is input, the process proceeds to S14 and it is checked whether the work transfer interval data is "0".

When the work transfer interval data input in the teaching data is "0" in S14, the work is suspended on the hanger 2a, so the process proceeds to S15 and the teaching data painting operation is started as it is. ,
The painting by the painting robot 3 is executed.

However, when the work transfer interval data is not "0" in S14, the signal (pulse) from the hanger detection switch 19 input in S13 is ignored, the pulse is counted, and the process of S15 is executed. do not do.

In S17 shown in FIG. 11, the work transfer interval data is compared with the number of pulses ignored in S16. For example, in the case of the work 1A, the work transfer interval data is "01". If the signal from 19 is ignored once, the process proceeds to S18, the pulse count is stopped, and the work transfer interval data is cleared to zero.

Therefore, when the hanger 2a with the next work is detected by the hanger detection switch 19, S1
Since the work transfer interval data is “0” in No. 4,
In S15, the coating operation is performed on the work 1A suspended from the hanger 2a.

Further, when the work 1B is continuously conveyed, as shown in FIG. 1, the hangers 2a are hung at every two intervals.

In this way, when the work 1B is conveyed, the hanger 2a with the work is conveyed after the two hangers 2a without the work. Therefore, since the work interval data is "02" in S14, the process proceeds to S16 and the first signal from the hanger detection switch 19 is ignored.

In this case, since the pulse count ignored in S17 is "1", the process of S18 is not executed.

When the second hanger 2a without a work is detected by the detection switch 19, since the work transfer interval data is not cleared to zero in S14, the process proceeds to S16 and the second signal is ignored and the pulse count is "2". And

Then, in S17 this time, the pulse count becomes "2", which is equal to the work conveyance interval data.
Moving to 18, the pulse counting is stopped and the work transfer interval data is cleared to zero.

As a result, when the third hanger 2a with a work is detected, the work transfer interval data is zero in S14, so the process proceeds to S15 and the work 1
Perform the painting work for B.

As described above, when the hanger 2a of the conveyor 2 is hung at an interval depending on the type of the work, the work interval data is input to the teaching data corresponding to the work. Even if a hanger without a work is detected by the signal from, it is possible to prevent the painting robot 3 from performing a painting operation by mistake.

In addition, the work transfer interval data input to the teaching data makes it possible to detect a hanger without a work each time even if the work transfer interval, that is, the number of hangers without a work is different depending on the work type. The coating work is performed only on the hanger having.

Further, since the work transfer interval data is input to the teaching data as described above, it is not necessary to separately provide a work detecting sensor, and there is no risk of malfunction due to erroneous detection of the sensor. Therefore, it is possible to use the existing system as it is and deal with it by changing the software.

In the above embodiments, the painting robot system has been described as an example, but it is needless to say that the present invention can be applied to other robots such as a sealing robot and a welding robot.

[0054]

As described above, in the robot control system according to the present invention, the work transfer interval input means inputs the number of hangers between the works suspended from the hangers of the conveyor so that the hanger detection switch does not work. Even if is detected, the detection signal can be ignored and the work for the next conveyed work can be surely executed. Therefore, it is possible to prevent the robot from erroneously operating on a hanger without a work even if the work transfer interval is different depending on the type of work, and it is not necessary to add equipment such as a separate sensor for work detection. It is also possible to prevent malfunction due to erroneous detection of the sensor. Moreover, since it can be realized by changing the software so that the presence or absence of the work can be discriminated by using the conventional equipment, the cost can be further reduced.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a coating system to which an embodiment of a robot control system according to the present invention is applied.

FIG. 2 is a perspective view of a painting robot.

FIG. 3 is a plan view showing a control device and a data setting device.

FIG. 4 is a diagram for explaining a work table.

FIG. 5 is a diagram showing work data corresponding to a type of work.

FIG. 6 is a flowchart for explaining a process executed by a data setting device.

FIG. 7 is a diagram showing teaching data of a work 1A.

FIG. 8 is a diagram showing teaching data of a work 1B.

FIG. 9 is a flowchart of a process of setting work conveyance interval data.

FIG. 10 is a flowchart for controlling the operation of the painting robot.

FIG. 11 is a flowchart for comparing pulse count and work transfer interval data.

[Explanation of symbols]

 1 Work 2 Conveyor 2a Hanger 3 Painting Robot 18 Control Device 19 Hanger Detection Switch 21 Data Setting Device 22 Pulse Transmitter 23 Coating Gun Control Device

Claims (1)

Claim: What is claimed is: 1. A conveyor in which hangers at predetermined intervals are hung, a work hung at the hangers and having an interval of at least every other hanger, and a hanger for detecting the arrival of the hangers. Depending on the detection means, a robot that performs work based on the detection signal from the hanger detection means by the playback data according to the type of the work, and the type of the work that is hung and conveyed by the hanger of the conveyor. The work transfer interval input means for inputting the number of hangers between the works, and when the number of hangers between the works input by the work transfer interval input means and the number of output signals of the hanger detection means match, depending on the type of the work A robot control system comprising: a control unit that controls the robot based on the playback data.