JPS59182090A - Driving mechanism of robot 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 [Field of Application of the Invention] The present invention relates to a robot arm drive mechanism.

[Background of the invention]

FIG. 1 shows an example of a conventional arm drive mechanism.

A first arm 4 is rotatably supported on a base 10, and a second arm 9 is rotatably supported at the tip of the first arm 4.

Reference numeral 1 designates a first drive motor fixed to a base 10, and a first double crank 2 is fixed to its rotating shaft.
between the double crank 2 and the first arm 4, a pair of first
The double links 3a and 3b are not installed properly. A cross section taken along the line A-A in this figure is shown in FIG. 2. Thereby, when the first double crank 2 is rotated, the first arm 4 is rotated in the same direction and by the same angle.

Reference numeral 25 shown in FIG. 1 is a second drive motor fixed to the base 10, and a second double crank 5 is fixed to its rotating shaft.

The double crank 5 and the second arm 9 are connected by a double link via the intermediate double crank 7 as described below. The intermediate double crank 7 is rotatably supported by a bearing 7a concentrically with the support shaft of the first arm 4. A BB cross section of this figure is shown in FIG. 3.

The second double crank 5 and the intermediate double crank 7 are 1
They are connected by a pair of second root-side double links 6a and 6b. 12a and 12b are crank pins installed in the second double crank 5, and lla and llb are crank pins installed in the intermediate double crank 7.

27th-mu 9 and intermediate double crank 7 are one pair (7)
They are connected by tuple links 8a and 8b. The crank pins lla and llb are commonly used to connect the double links 8a and 8b to the intermediate double crank 7. As a result, when the second double crank 5 is rotated, the intermediate double crank 7 and the second arm 9 are rotated in the same direction and by the same angle.

In the conventional robot arm drive mechanism as described above, the first arm 4 can be driven by the first drive motor I, and the second arm 9 can be driven by the second drive motor 25. However, there are the following problems.

When the 27th member 9 is attempted to be rotated significantly, the second root side double link 6a (or 6b)
lb, 12b (or ha, 12a) and the rotation angle is limited. The range in which the second arm 9 can rotate without causing such interference changes depending on the attitude of the first arm 4.

Which double link and which crank pin interfere with each other are crank pin 11a+ 122 and crank pin 11b.
, 12b, as shown in the example in FIG.
.

When the crank pin 12a is also made longer, the longer crank pin Ila, 12a interferes with the link 6a connected by the shorter crank pin.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a robot arm drive mechanism that reduces rotational obstruction of the second arm due to interference between the crank pin and the link and has a wide movable range.

[Summary of the invention]

In the conventional robot arm drive mechanism (Fig. 1), interference between the crank pin and the link occurs because of the two crank pins lla and llb for the intermediate double crank 7.
This is because they protrude in the same direction. For this reason, interference cannot be avoided even if the two crank pins lla and IIEI are lengthened and shortened. As a result of research into the generation mechanism of the above-mentioned interference, the present invention has found that in order to reduce this interference,
The above-mentioned two crank pins lla and llb may be made to protrude in opposite directions to the intermediate double crank 7, and the pressure bonding layer is completed. In order to expand the movable range of the second arm based on the above principle, the present invention includes a first arm rotatably supported on the base, and a first arm movably supported on the optical end of the first arm. the first double crank is fixed to the shaft of the first drive motor fixed to the pace, the first double crank and the first arm are connected via a double link, and A second double crank is fixed to the shaft of a second drive motor fixed to the pace, and an intermediate double crank is provided between the second double crank and the second arm. The intermediate double crank is rotatably supported concentrically with the support shaft of the first arm, and the intermediate double crank and the second double crank are connected by a second base side tuple link, and the intermediate double crank and the second arm are rotatably supported. In a robot arm drive mechanism in which the two are connected by a second tip-side double link, one link of the pair of links constituting the second root-side double link is attached to one side of the intermediate double crank. Along with connecting, 1
It is characterized in that the other link of the pair of links is connected to the opposite surface of the intermediate double crank.

[Embodiments of the invention]

Next, one embodiment of the present invention will be described with reference to FIGS. 4 to 6.

This embodiment is an improvement by applying the present invention to the conventional robot arm drive mechanism shown in FIGS. 1 to 3. FIG. 4 corresponds to FIG. 1 of the conventional device, and FIG. 6 corresponds to FIG. 2 in the conventional device, and FIG. 6 corresponds to FIG. 3 in the conventional device.

For convenience of explanation, components in this embodiment that are the same or similar to those of the conventional device will first be described.

The first arm 16 is rotatably supported on the base 23. A twenty-seventh arm 22 is rotatably supported at the tip of the first arm 16.

When carrying out the present invention, the pivot point of the second arm 22 is not necessarily limited to the tip of the 17th arm 16;
It can also be pivoted near the center of the

In the present invention, the tip of the first arm is a general term for a portion away from the center of rotation of the first arm.

A first drive motor 13 is fixed to a base 23, and a first double crank 14 is fixed to its rotating shaft. As shown in FIG. 5 (A-A sectional view in FIG. 4), the 17th arm 16 and the first double crank 14 are connected to the first double link 15.
a and 15b, and the first arm 16 is interlocked with the first double crank 14.

Reference numeral 17 shown in FIG. 4 is a second drive motor fixed to the base 23, and a second double crank 18 is fixed to its rotating shaft. On the other hand, the intermediate double crank 20 is connected to the first arm 1.
It is rotatably supported on the base 23 by a bearing 20a concentrically with the support shaft of No. 6.

The above-mentioned components in the configuration of this embodiment are the same or similar to those of the conventional device shown in FIGS. 1 to 3.

In the present invention, a pair of links constituting the second root side double link are respectively connected to both sides of the intermediate double crank.

In this embodiment, as shown in FIG. 4 and FIG. 6, which is a sectional view taken along line B-B, the pair of second root-side double links 19a and 19b are connected to crank pins 24a and 19b, respectively.
, 241) to the second double crank 18. On the other hand, crank pins 26a and 26b are respectively installed on both sides of the intermediate double crank 20, and the link 19a is connected to the crank pin 26a, and the link 19b is connected to the crank pin 26b, respectively.

As shown in FIG. 6, one link 21b of the second front end side double link is connected to the intermediate double crank 20 by sharing the crank pin 26b, and the upper end of this link 21b is connected to the second arm 22. Pivotally attached for free movement.

'' One end of the other link 21a, which forms a pair with the two-part link 21b to form a second tip-side double link, is connected to the intermediate double crank 20 by a crank pin 27, and the other end of the link 21a is connected to the intermediate double crank 20 by a crank pin 27. is rotatably attached to the second arm 22.

0 is the rotation center point of the intermediate double crank 20.

A line 11 is the bisector of the angle where the crank pins 26a, 26b look at the center point O, and a line 12 is the bisector of the angle where the crank pins 26b, 27 look at the center point O. In this embodiment, the above two lines p, 1. The intersection angle of x2 is 90°
The settings are as follows. That is, in this embodiment, the second root side double links 19a, 19b, m
A phase difference of 90' is provided between the two distal end side double links 21a and 21b.

When carrying out the present invention, the phase relationship between the second root-side double link and the second tip-side double link can be set arbitrarily, but if an appropriate phase difference is provided as in this example, This is advantageous in order to further reduce interference between the double link that drives the two arms and the crank pin.

In this embodiment, when the second double crank 18 is rotated by the second drive motor 17 to drive the second arm 22, the rotation is inhibited by the interference of transmission-related members between the crank pin 24b and the link 19a. However, since a rotation angle of approximately 36o0 is allowed, there is no problem in practical use. The rotatable range described above is not affected by the attitude of the first arm 16.

〔Effect of the invention〕

As explained above, the robot arm drive mechanism of the present invention connects one link of the pair of links constituting the second base double link to one side of the intermediate double crank, and By connecting the other of the pair of links to the opposite surface of the intermediate double crank, it is possible to avoid interference with the second arm's rotation due to interference between the crank pin and the link, and to obtain a wide range of motion. It has excellent practical effects.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing an example of a conventional robot arm drive mechanism, FIG. 2 is a sectional view taken along the line AA in FIG. 1, and FIG. 3 is a sectional view taken along the line BB in FIG. FIG. 4 is a partial cross-sectional view showing one embodiment of the robot arm drive mechanism of the present invention, which corresponds to FIG. 1 of the conventional device, and FIG.
A sectional view, and FIG. 6 are BB sectional views of FIG. 4. 13... First drive motor, 14... First double crank, 15a, 15b... First double link,
16... First arm, 17... Second drive motor, 18... Second double crank, 19a, 19b
...Second root side double link, 2o...Intermediate double crank 1 21a, 21b...Second tip side double link, 22...Second arm, 23...Pace,
24a, z4b, 26a, 26b+ 27'...
7 ” Kuhin. Agent Patent Attorney Tadashi Akimoto Actual Figure 1 8□B Figure 21 Figure 3 Figure 9 4 Figure 5 Figure 6 Figure 2

Claims (1)

[Claims] The first arm is rotatably supported on the base, and the second arm is rotatably supported on the optical end of the first arm. 1st
At the same time, the first double crank and the first arm are connected via a double link, and a second drive motor is attached to the shaft of a second drive motor fixed to the base.
A double crank is fixed thereto, and an intermediate double crank is provided between the second double crank and the second arm, and the intermediate double crank is rotatably supported concentrically with the support shaft of the first arm. , the above intermediate double crank and the second double crank are connected by a second root side double link, and the above intermediate double crank and the second double crank are connected by a second root side double link.
In a robot arm drive mechanism in which the arm is connected to the arm by a second tip-side double link, one link of the pair of links constituting the second base-side double link is connected to one side of the intermediate double crank. In addition to connecting to
A robot arm drive mechanism characterized in that the other link of the pair of links is connected to the opposite surface of an intermediate double crank.