JPS632683A - Industrial robot - Google Patents

Abstract

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

Description

[Detailed description of the invention]

"Industrial Application Field" The present invention relates to an industrial robot having an automatic program switching device suitable for automatic processing systems for high-mix, low-volume production. "Conventional technology and its problems" Generally, when using a robot to perform a specified process on a workpiece, the robot's work content changes every time the lot (type) of the workpiece changes, so the operation Program changes are required. Therefore, for example, in an automatic processing line, such as an automobile painting line, in which workpieces are suspended on hangers and successively fed one by one to the working position of a robot, 10 workpieces of one type may be suspended. A so-called dummy hanger is installed between the hung hanger and the subsequent hanger on which other types of workpieces are hung.
By having the robot detect this dummy hanger, the program can be automatically changed. However, in order to carry out the above method, it is necessary for the operator to artificially install dummy hangers at the breaks between lots.Especially in lines that perform high-mix, low-volume production, there are many dummy hangers. There is a problem in that it is necessary to install a hanger, and the installation requires a lot of labor. The present invention has been proposed in view of the above circumstances, and an object of the present invention is to reliably change the operation program of a robot without providing a dummy hanger. "Means for Solving the Problem" In order to achieve the above object, the present invention stores a program of operations to be performed by a robot in a storage means for each lot of workpieces, and prevents workpieces from being suspended. The passage of an empty hanger is detected by a detection means consisting of a sensor such as a microswitch, and the number of passing empty hangers detected by the detection means is counted by a CP.
U is made to count, and the CPU as a comparison means compares it with the set value, and according to the comparison result, from the storage means,
Read out other operating programs and use C as a control means.
This allows the PU to control the robot. "Function" When changing the lot of workpieces conveyed by the conveyor, if a certain number or more of empty hangers are provided at the break between lots, the passage of these empty hangers will be sequentially detected and the number of passing pieces will be counted. If a predetermined number or more have passed, it is determined that the lot has been changed and the program is changed. "Embodiment" Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a painting line to which the present invention is applied, and reference numeral l in the figure represents a conveyor. This conveyor! The work A I' A t・A,..., Bl・
Hanger 2 on which B,・B,... can be hung.
2... are provided, and these hangers 2
As shown in FIGS. 2 and 3, the primary hanger 3 is directly attached to the conveyor l, and the primary hanger 3 is
a secondary hanger 4 suspended from the secondary hanger 4;
It is composed of a tertiary hanger 5 that is suspended from the tertiary hanger 5 and directly supports the workpiece A n (B n). Note that the tertiary hanger 5 is provided only when a workpiece is present. - On the other hand, numeral 6 is a robot, and this robot 6 is
It is operated by a robot control device 7 to cause a tool 9, such as a painting gun, attached to the tip of an arm 8 to perform a predetermined operation. Next, the configuration of the robot control device 7 will be explained with reference to FIG. 4. Sign! 0 is a CPU, and a main memory 11 for storing programs is connected to this CPU10, and a work auxiliary storage device 12 is connected to this main memory 11 for storing programs for each lot regarding the work contents of the robot. ing. Further, an interface I3 is connected to the CPU10, and via this interface 13, the robot 6, the synchronizer 14 of the conveyor 1, and the secondary hanger 4 (or primary hanger 3) suspended from the conveyor 1 are connected. start switch 1 operated by the passage of
5. Tertiary hanger 5 provided below the start switch 15 (i.e., a hanger on which the workpiece is suspended)
A work presence detection switch 16 is connected to detect the passage of the workpiece. The synchronizer I4 is configured to output a synchronization signal to synchronize the conveyor 1 and the robot 6 based on the output of the pulse transmitter 17. Next, the operation of the robot control device will be explained with reference to FIG. Note that Sn in the following description indicates the n-th step in the flowchart. Start Sl: When the regeneration start switch of robot 6 is turned on,
The contents of the memory (the forwarding counter that is incremented each time an empty hanger passes, and the counter clear flag for this forwarding counter) are initially cleared (reset), and the program number corresponding to each work lot (each lot is (number of the program corresponding to processing the first workpiece) is registered in the robot control panel 7. S7. Ra the program number of the first worklot.
Set to J. S3: Read the reproduction data corresponding to ra J from the auxiliary storage device 12 and read it into the main memory 11. Proceed to the next step 85 on the condition that the S4 robot start switch is ON. S5: When the hanger 2 moves in the direction of the arrow in FIG. entered,
“Work present” is stored in the main memory 11. Also,
When there is no work (when C4 to C3 pass)
Since the work presence detection switch 16 does not operate,
[Work present] is not stored. And) 1 nga 2
As the process progresses further, the robot start switch 15 is activated, and when this robot start switch I5 is turned ON, it is determined whether "work present" is stored in the main memory II, and if YES, the robot start switch 15 is activated. 88~S
, proceed to the robot operation process, and if NO, proceed to the SIO
Proceed to the idle feed process of '=S+3.

[Robot operation processing]

S8: Determine whether or not the counter clear flag has been cleared. If YES, proceed to S8. If NO, reset the forwarding counter. After setting the counter clear flag (S7), proceed to S8. . S8: While reading and reproducing the teaching data for the relevant workpiece from the main memory 11, CPtJlo controls the robot 6 and performs predetermined processing on the workpiece A1. S, determines whether the predetermined processing has been completed for the two workpieces, and returns to S4 on the condition that it has been completed (YES), and the next workpiece (A,) is activated when the robot start switch I5 is pressed. Wait for it to work.

[Dry feed processing]

S. ;Add 1 to the count value of the forwarding counter. Sl,: It is determined whether the count value of the forwarding count has reached 3 or not, and in the case of No, it is determined that the empty hanger is simply passing, and the process returns to S4, and therefore, the robot 6 does not operate. Wait for the next hanger 2 to pass. - direction, C, -C, ・C3, when three consecutive empty hangers pass and the work An is switched to the work Bn, the count value becomes 3, a YES judgment is made, and the next Proceed to 91. Sl! The nib program is switched from "a" to ra+IJ, that is, the program for the next worklot Bn. S13: After setting the counter clear flag, repeat the steps S and below. That is, ra+
The program for 1j is read from the auxiliary storage device 12, and predetermined processing is executed for the next lot of work Bn. In the above embodiment, in order to clearly distinguish between empty hangers simply passing through and empty hangers artificially provided for lot change, the number of empty hangers adopted as a lot change command is set to 3. Although the number is set, it is of course possible to set it to a larger number or a smaller number. Further, the specific shape of the hanger and the method of the sensor for detecting the passage of an empty hanger are not limited to the above-mentioned embodiment, and it goes without saying that other methods may be used. "Effects of the Invention" As is clear from the above explanation, the present invention stores a program of operations to be executed by a robot in a storage means for each lot of workpieces, and stores empty hangers on which no workpieces are suspended. The passage is detected by a detection means consisting of a sensor such as a microswitch, and the number of passing empty hangers detected by the detection means is counted by a CPU as a counting means.
The robot is compared with the set value by U, and the pond operation program is read out from the storage means according to the comparison result, and the robot is controlled by the CPU as the control means. The effect is that the robot program can be easily changed in response to lot changes simply by providing an empty hanger.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention. Figure 1 is a layout of a conveyor for conveying workpieces and a robot, Figure 2 is a side view of the hanger, Figure 3 is a front view of the hanger, and Figure 4 is a diagram showing the arrangement of the robot. 1 is a block diagram of the control device, and FIG. 5 is a flowchart of the control operation. 1...Conveyor, 2...Hanger, 3
...Primary hanger, 4...Second hanger, 5...Third hanger, 6...Robot body, 7...Robot Control device, IO...
...CPU, I+...Main memory, 12...
... Auxiliary storage device, 15 ... Start switch, 16 ... Work presence detection switch.

Claims (1)

[Claims] In an industrial robot configured to transport a large number of workpieces by hanging them on a hanger, and to perform predetermined processing using a work tool held on the robot body within the working range of the robot body, the operation to be performed by the robot body. A storage means that stores programs for each lot of workpieces;
A detection means for detecting the passage of an empty hanger on which no workpiece is suspended; a counting means for counting the number of passing empty hangers detected by the detection means; and whether the count value of the counting means has exceeded a set value. and a control means for reading an operation program for a lot different from the currently set operation program from the storage means and operating the robot according to the determination result of the determination means. An industrial robot featuring: