JPS6025696A - Collision previous avoidance system of automatic machine - 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 The present invention provides a system for preventing collisions between automatic machines by equipping the movable parts of the automatic machines with a detection device to automatically stop them so as not to cause harm to people due to unexpected movements of the automatic machines. Regarding prevention devices.

Recently, automatic machines such as robots whose sole purpose is to move freely in space have been rapidly increasing, and the performance of these automatic machines is
We are moving towards allowing more complex or movement. This kind of automatic machine turning involves teaching work to teach the machine how to do the work. During teaching work, etc., it is necessary for people to enter the movable area of the machine, but in this case, due to a malfunction of the machine, the movable parts of the machine may move unexpectedly and cause harm to the person.

Until now, development has focused on improving the performance of machines, and as a result, safety equipment measures tend to be delayed, and in reality, no special consideration is given to safety, and in practice, it is difficult to prevent machine malfunctions. Disasters occur in which people are injured.

SUMMARY OF THE INVENTION In order to completely prevent the above-mentioned disasters, it is an object of the present invention to provide a collision prevention device for an automatic machine that includes a deformable detection device in the movable part of the automatic machine and automatically stops the machine.

The structure of the present invention that achieves this object is an automatic machine having a movable part that moves freely in space, and a deformable pressure-receiving part that protrudes from the movable part in the direction of movement of the movable part. In a collision prevention device for an automatic machine that detects the amount of deformation of the movable part and stops the movement of the movable part within the range of the deformation, the pressure receiving part communicating with the pressure detector is formed of a flexible pressure receiving pipe. Branch-like pressure receiving pipes branched from the main pipe communicating with the pressure detector are arranged on the surface of the movable part, or distributed over the surface of all the moving parts, and a fluid with good pressure propagation is sealed inside the pressure receiving pipe. It is characterized by

Here, with reference to FIGS. 1 to 4, the embodiment 'fr:
explain. FIG. 1 shows a simple wedge-shaped trajectory of an arm existing in an automatic machine (herein referred to as a robot), and shows an arm consisting of three links 1, 2, and 3. In reality, the trajectory is very complex, but it is simplified in FIG. 1 for the sake of explanation. Links 1, 2.3 can move freely in space, but generally U IJ
It rotates around an axis that is the proximal end of at least one of the links 1, 2.3. Therefore, arm 1 of 5 lopits,
2. It is not possible to determine which of the three points will be the most advanced point of movement, that is, the part that moves the most during movement. For example, in the state of the 11th state (b) and (c), if link 21
, 2# move clockwise around the upper end of link 1, the tip of link 2'' and link 2' in links 2'' and 3''.

3', the tip of the link 3' becomes the leading edge of movement. Although this large degree of freedom is a characteristic of robots, it also carries the risk of contacting other objects with all moving parts.

Furthermore, the arms of robots are often made in a shape that is bent in 93 dimensions as shown in FIG. 2, rather than as an rN-line link as shown in FIG. Looking at it this way,
Any part of the arm can touch other objects.

In this example, regardless of the shape of the arm or link of the movable part,
Since those surfaces and ridge lines (line portions on the bending direction side of arms and links) are the leading edge of the movement, as shown in Fig. A flexible pressure receiving pipe 5 is attached. This pressure receiving tube 5 is filled with a fluid such as water having good pressure propagation characteristics. The detection section is connected to a pressure detector 7 via a fitting 6 (see FIG. 3) on the pressure receiving pipe 5. An electric wire 8 for a detection signal extends from the pressure detector 7.

Fig. 3(a) shows the pressure receiving pipe 5, the fitting 6, and the pressure detector 7.
It shows. With this structure, when any part of the pressure receiving pipe 5 is compressed, the pressure changes uniformly in any part, and the change is accurately transmitted to the pressure detector 7.

FIG. 3(b) shows a case where a branched movable part is detected by one pressure detector 6. 1. A branch pipe 10 is provided at an appropriate location of a connecting pipe 9 made of, for example, a steel pipe, and a cock is installed at the tip of the branch pipe 10. 11 and connect the pressure receiving pipe 5 shown in FIG. 3(a) from necessary locations in the same manner. Here, the necessary locations were selected because if there are many branch pipes 10, there is little need to take safety measures for all moving parts, so open the cocks 11 in the parts where there is a risk of safety collision. Just leave it there.

The pressure detector 7 may be of any type that is generally commercially available, and the drive section stop circuit may be a general electric power a circuit.

In such a structure, care must be taken to determine how long the movable part 4 can be stopped from deforming due to the total received pressure %'5.

That is, it is necessary to completely stop the movement of the movable part 4 from the time when the pressure receiving tube 5 attached to the movable part 4 of the robot comes into contact with the object until the main body of the movable part 4 approaches. Here, the speed v1 of the movable part 4, the reaction time t1 from contact with the pressure receiving pipe 5 to the stop of the movable part 4, and the speed of the moving part 40 from the surface of the pressure receiving pipe 5 to
Assuming that the distance (height) to the main body is H, the relationship I-1>vl is required. That is, as shown in FIG. 4, when the pressure receiving tube 5 comes into contact with an object and the internal pressure inside the tube rises until a signal is generated from the pressure detector 7, +1fJt1 and this signal cause the drive source to enter a stop operation. During the time t2, the movable part 4 moves at an initial speed (initial speed). Further, the braking characteristics of the drive source can be considered by linear approximation as shown in FIG. Therefore, the distance S that the movable part 4 moves during the reaction time is expressed by the following formula.

S−v(tl+”2)+2vtsIf safety is taken into account in this equation, it becomes Svt.

Therefore, if it is 14:)vt, it will be a sufficient safety design.

The height H of the pressure receiving tube 5 is desirably 10 degrees or less if the function of the opening is to be felt strongly. In addition, the reaction time t depends on the characteristics of the control circuit, but in our economical design, it is a chopstick. It is about seconds. Therefore, the safe speed V of the moving part is 100 per second.
It must be lower than Nawate. In the lower bit of Hades,
In order to increase work efficiency, the number of stomachs may be reduced to about one stomach per second.
Therefore, it seems that this embodiment can only be applied to slow movements. 711'L, even if the design is designed to perform fast motion in actual work, it is sufficient to provide a control circuit that makes the speed of the actual work m during teaching, and even in a normal design, the speed is set to slow during such teaching. There are many methods. And when a person follows the motion of a machine with his eyes, 1 per second
The speed of 00 easy is in the fast range. As a result, a sufficiently safe design is possible even if the height of the pressure receiving part 5 and the characteristics of the control circuit are as described above.

In this embodiment, the need for one detector for each movable part is reduced, so the number of detectors can be reduced.

In this way, if the amount of deformation (height) ()k of the pressure receiving tube 5 is made larger than the product of the speed V of the moving part and flJJ tO at the time of reaction, a direct hit to the main body of the moving part can be avoided.

Since the deformed needle H and the reaction time t naturally have appropriate values based on general design values, if the speed V of the moving part is selected at around 100 degrees per second, the device can be sufficiently achieved. + iJ Noh. When teaching, a speed of 100 m/s is not a speed that feels great.

The pressure receiving tube can be selected from a material that has a characteristic sound similar to a vinyl tube depending on the usage conditions, and can be inexpensive.

By configuring the pressure receiving pipe to have a structure in which all the detection parts are connected to a tubular or connecting pipe, a wide range can be covered, and the detection profit can be significantly reduced, making it economical.

By appropriately selecting the structure and materials mentioned above, it is possible to stop the machine within a compressive force comparable to that of a human finger.
You can avoid serious injuries. Of course, it goes without saying that collisions between solid members can also be avoided.

[Brief explanation of drawings]

1 to 4 show embodiments of the present invention, in which FIG. 1 is an explanatory diagram showing an example of movement of the movable part, FIG. 2 is a configuration diagram showing the relationship between the movable part and the pressure receiving pipe, and FIG. Figure (a) is a configuration diagram showing an example of a pressure receiving part, Part 3) is a configuration diagram of a branched pressure receiving part,
FIG. 4 is a diagram showing the relationship between speed and delay time. In the drawings, 1, 2, 2', 2', 3, 3', 3'' are links, 4 is a movable part, 5 is a pressure receiving pipe, and 7 is a pressure detector. Patent applicant Mitsubishi Heavy Industries, Ltd. Patent Attorney Mitsuishi Shibu (and 1 other person) Figure I! Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] An automatic machine with movable parts that moves freely in space,
A deformable pressure-receiving part is provided that protrudes from the movable part in the direction of movement of the movable part, and the entire deformation amount of the pressure-receiving part is detected and the movement of the movable part is automatically stopped within the range of the deformation amount.
In a mechanical collision prevention device, the pressure receiving part communicating with the pressure detector is formed of a fully flexible pressure receiving pipe and is piped to the surface of the movable part, or branched from the main pipe communicating with the pressure detector. A collision prevention device for automatic machinery characterized by branch-like pressure receiving tubes being distributed over the surface of a movable part and a fluid with good pressure propagation being completely enclosed inside the pressure receiving tubes.