JPS637284A - 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 used for transferring and assembling work objects, and more specifically, the hand part is driven by a linear motor to move up and down. It is related to industrial robots.

Conventional technology This type of industrial robot is disclosed in Japanese Patent Application Laid-open No. 61-61776.
There is something shown in the publication. As shown in FIG. 3, a hand portion 3 that is driven vertically by a linear motor 2 is disposed at the tip of a horizontal multi-joint arm 1. The reason why the hand unit 3 is directly driven vertically by the linear motor 2 is that the vertical movement speed of the hand unit 3 is faster than that of previous drive methods (rotary motor + pole screw, etc.). This is because it is possible to improve accuracy and is advantageous in control and teaching.

Problems to be Solved by the Invention By the way, in the conventional example described above, since the hand section 3 is directly attached to the movable section of the linear motor 2, there are the following problems.

(2) Since the gravity of the movable part and the hand part 3 always acts on the linear motor 2, a large amount of power must be used to drive the hand part 3 upward, which leads to an increase in the size of the linear motor 2. Furthermore, if a small linear motor 2 is used, heat generation will increase.

(2) When the power is turned off, the hand section 3 falls due to gravity, but it is difficult to provide a brake on the linear motor 2 to prevent this.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides an industrial robot in which the hand section is driven by a linear motor to move up and down. The linear motor and the hand section are interlocked, and the direction in which the rotation transmission body is rotated by the gravity of the movable part of the linear motor is opposite to the direction in which the rotation transmission body is rotated by the gravity of the hand part. are each connected to a rotation transmitting body.

According to the present invention, the gravitational force acting on the linear motor is reduced by the gravitational balance between the movable part and the hand part. Therefore, the linear motor can be made smaller and the problem of heat generation can be solved.

Further, according to the present invention, the gravity fall of the hand part when the power is turned off can be prevented or reduced by the gravity balance, and it is easy to incorporate a brake mechanism into the rotation transmitting body. Therefore, the problem of gravity falling can be dealt with more effectively.

Embodiment The embodiment of the present invention shown in FIGS. 1 and 2 is an improved version of the hand section and its drive system of the industrial robot shown in FIG. 3.

A linear motor 11 is attached to the tip of the arm 10,
A movable part 13 is guided and supported by the fixed part 12 so as to be movable up and down. The movable part 13 of the linear motor 11 is fixed to a timing belt 15 of a rotation transmitting body 14. The rotation transmitting body 14 includes a pair of upper and lower boots IJ16.17, and the timing belt 15 is suspended between these pulleys L6.17.

Further, a hand portion 19 that is guided in the vertical direction by a guide shaft 18 is disposed at the tip of the arm 10, and an upper portion 20 of this hand portion 19 is fixed to the timing belt 15.

As is clear from FIG. 1, the movable part 13 of the linear motor 11 is fixed to one side of the timing belt 15, and the upper part 20 of the hand part 19 is fixed to the other side of the timing belt 15. The timing belt 15 is rotated clockwise in the figure by the gravity of the movable part 13, and the timing belt 15 is rotated by the gravity of the hand part 19.
5 is rotated counterclockwise in the figure. Therefore, the movable part 13
If the gravity of the hand portion 19 is approximately the same as that of the rotation transmitting body 1
The timing belt 15 of No. 4 is gravity balanced and can prevent gravity from acting on the linear motor 11. In this embodiment, the hand section 19 and the movable section 13 are set in such a state that the gravity is balanced.

As shown in FIG. 2, the pulley has a pair of friction plates 23, 24, a spring 25 that presses the - side friction plate 24 against the other friction plate 23 fixed to the pulley shaft 22, and the - side friction plate 23, 24. A brake mechanism 21 consisting of a solenoid 26 that separates the friction plate 24 from the other friction plate 23 is attached. When the power is turned off, the current to the solenoid 26 is cut off, and both friction slopes 23 and 24 come into pressure contact with each other, and the rotation transmission body 14
Brake action is applied to

In FIG. 1, reference numeral 27 denotes a position sensor for detecting the vertical position of the movable part 13 and, by extension, the vertical position of the hand part 19, and can be configured with a line sensor, for example.

The present invention can be configured in various ways other than those shown in the above embodiments. For example, as the rotation transmitting body 14, a steel belt fixedly attached to both pulleys can be used.

Effects of the Invention According to the present invention, the influence of gravity acting on the linear motor can be reduced by the gravitational balance between the movable part of the linear motor and the hand part. can solve the problem of heat generation.

Further, according to the present invention, it is possible to prevent or reduce the gravity fall of the hand portion when the power is turned off by the gravity balance.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part of an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of a main part of a rotation transmitting body, and FIG. 3 is a perspective view of a conventional example. 11−−−−−−−・−・−・−・−・−・−−−−−
～・−Linear motor 13−−−−−−−−−・−−−
−−・・−−−−−−−−1−−−・−・Movable part 14−
・−・−・−−−−１・−・−・−−−−−１−−・−
・Rotation transmitting body 19-------・--1-------・-
m=----・-----m=-----・Hand part 21
−・−１−−−−−・・−−−−−−−−−・・・−−
−−−−−・−・Brake mechanism. Figure 1 Figure 2

Claims (3)

[Claims] (1) In an industrial robot in which the hand part is driven by a linear motor and moves up and down, the linear motor and the hand part are linked via a rotation transmission body, and the rotation transmission body is driven by the gravity of the movable part of the linear motor. An industrial device characterized in that the linear motor and the hand section are respectively connected to the rotation transmission body so that the direction in which the linear motor and the hand section are rotated is opposite to the direction in which the rotation transmission body is rotated by the gravity of the hand section. robot. (2) The industrial robot according to claim 1, wherein the gravity of the hand portion and the gravity of the movable portion of the linear motor are substantially the same. (3) The industrial robot according to claim 1 or 2, wherein the rotation transmitting body has a brake mechanism.