JPS59214597A - Collision-avoidance system for movable arm - 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 [Technical Field of the Invention] The present invention relates to a collision prevention device (= related to It is.

[Technical background of the invention and its problems]

Generally speaking, industrial robots operate according to a predetermined program, so if a foreign object enters the operating area of its movable arm, there is a risk of a collision.

To prevent this, conventional methods used pressure-sensitive tape or wires to detect contact with foreign objects. However, the detection range is narrow, making it difficult to safely prevent collisions.

[Purpose of the invention]

An object of the present invention is to provide a highly safe movable arm collision prevention device in which a projector and a light receiver are attached to a movable arm, and collision prevention is performed by detecting the approach of a foreign object using reflected light from the foreign object. .

[Summary of the invention]

The present invention attaches a light emitter and a light receiver to the tip of a movable arm, and detects when the light beam projected from the emitter hits a foreign object and reflects the reflected light with the receiver. It is a collision prevention device with a movable arm that detects and prevents collisions, and uses a rotating reflector to move around in order to detect the approach of two foreign objects over a wide range.

[Embodiments of the invention]

Figure 1 (shows the basic configuration of a dual-reflection photoelectric switch).

In FIG. 1, when the original beam projected from the light emitter IA of the photoelectric switch 1 hits a foreign object 2 (2) falling within the detection distance and is reflected, a part of the reflected light is transmitted to the light receiver IBi 2 (return 9), Operate 1.

It should be noted that since the foreign matter 2 is generally in a deficient shape and the amount of light reflected back to the light receiver IB is small, if necessary, the specific foreign matter is coated with an appropriate coating or plate to increase the reflection efficiency.

FIG. 2 shows an embodiment of the present invention.

In FIG. 2, reference numeral 3 denotes a rotating arm that rotates with the rotation of a rotating shaft 4, and a hand 5 is used to perform a predetermined work.

Two sets of photoelectric switches 1 are attached to the tip of the rotating arm 3 facing in opposite directions.

This (2) makes it possible to prevent collisions when turning in both directions of arrows A and B.

FIG. 3 shows an example of a collision prevention circuit. When the drive circuit 3A of the rotating arm 3 is turned on, the emitter IA starts emitting light, and the light reflected by the foreign object 42 is received by the receiver IB. Then, the emergency stop circuit 3B of the swing arm 3 is operated via the amplifier circuit IC to bring the swing arm to an emergency stop.

The following (1) Figure 4 (2) shows another example of the photoelectric switch used. (A) is a top view, (B) is a side view,
(C) is a vertical view.

In Fig. 4, in order to expand the detection range of foreign objects (
Second, the optical axis is rotated using a rotating reflector.

That is, 6 is a reflector tilted at 45°, and motor 7 is
The optical axis of the light beam projected from the projector IA is rotated by this (2). Note that 8 is a mounting plate that supports the motor 7 on the mounting base 10 (2).

This constitutes an omnidirectional photoelectric switch that scans and detects foreign objects within the detection distance of the yoke H around the rotation axis H.

However, since this area must not be detected as a foreign object in the range D (the second is where the mounting base 10 is 1),...
The light is directed away from the direction 42 where the light cannot be detected.

FIG. 5 (2) shows an embodiment of a collision prevention device using the above-mentioned omnidirectional nine-way switch.

FIG. 5 shows an omnidirectional photoelectric switch attached to the movable arm of an articulated robot. The tip ζ2 of the movable arm 3 is attached in the vertical direction.

FIG. 6 shows an example of the collision prevention range in FIG. When this occurs, the omnidirectional photoelectric switch (2) can detect foreign objects in the area between the curves Y and X of the detection distance R and prevent collisions.

〔Effect of the invention〕

As explained above, according to the present invention, a projector and a light receiver are attached to a movable arm, and the intrusion of a foreign object is detected without contact using reflection from a foreign object, and measures such as an emergency stop are taken. The foreign object detection range and detection distance are sufficiently large, and collisions can be safely prevented.

[Brief explanation of the drawing]

Figure 1 shows the basic configuration of a reflective photoelectric switch.
FIG. 2 is a block diagram showing an embodiment of the present invention, FIG. 3 is a circuit diagram showing an example of a collision prevention circuit, and FIG. 4 is a block diagram showing an example of an omnidirectional photoelectric switch used in the present invention (2). FIG. 5 is a three-dimensional view showing another embodiment of the present invention using an omnidirectional photoelectric switch, and FIG. 6 is a plan view showing the foreign object detection range in FIG. Mirror IA Emitter 7 Motor 1B Receiver 8 Motor mounting plate 2 Foreign object
9A, 9B Fixed reflector 3 Movable arm 10
Mounting base 4 Swivel axis 11 First movable arm 5 Hand (8733) Agent Patent attorney Yoshiaki Inomata (and 1 others)
(name) Figure l Figure s 2 Same number
5 Figure 6

Claims (3)

[Claims] (1) A projector that is attached to the tip of the movable arm (2) and projects a light beam, and a light receiver that receives the reflected light that is reflected back from the projector (2) and a photoelectric switch for detecting the presence of a foreign object based on the light reception signal of the light receiver. (2) A rotating reflector is provided, which reflects the light beam projected from the projector in the right angle direction (two directions), and reflects the reflected light from the foreign object in the right angle direction (two directions), and returns it to the receiver (two directions), and the photoelectric switch is mounted on a circular surface. A collision prevention device for a movable arm according to claim 1 so as to be able to scan in all directions. (3) Collision of the movable arm according to claim 2, which is provided with a fixed reflecting mirror that reflects the light beam in two directions (in two directions) so that the light beam within a certain angle of the running difference range does not return to the light receiver. Prevention device.