JPS6260231B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Industrial Application Field The present invention relates to an industrial robot arm, and more specifically, an arm consisting of a multi-jointed body can be bent in any direction, and the wrist axis can be adjusted as necessary. It is used in the field of industrial robots that can rotate.

(b) Prior Art An industrial robot arm, for example, performs a predetermined displacement operation using power from a drive source of the robot body, and has a wrist attached to the tip of the arm perform a series of tasks on a work object. will be adopted.

Various such arms have been proposed in the past, but for example, an arm 1 as shown in FIG.
An internal link 2 with tooth surfaces 2A carved on both ends is employed, and the tooth surfaces 2A are arranged in a row so as to mesh with each other. And each internal link 2
is rotatably supported by a support body 5 of one of the two external links 4 via a pin joint 3 at two positions on the left and right sides thereof, so that it can be bent.

In such an arm 1, as shown in FIG. 2, for example, when an external link 4a at one end is fixed and an internal link 2a supported by the external link 2a is rotated in the direction of arrow 6, the internal link 2b connects the pin joint 3b. Rotates in the direction of arrow 7 around the center. At this time, external link 4a
The other external link 4b adjacent to the external link 4b also rotates along the circumscribed arcuate surface 4A. Such a bending action sequentially causes the internal link 2d and external link 4d at the tip.
When the distance is extended to , the arm 1 can be made to move flexibly. Furthermore, when the internal link 2a is rotated in the direction of arrow 8 as shown in FIG. sign 9
It can also be rotated in any direction.

However, in such an arm, the angular area of the tooth surface carved in the internal link is small, and there is a drawback that the bending angle between the internal links and the external link cannot be made large. In addition, the arm has low rigidity and the tooth surfaces are in point contact, making it impossible to transmit large forces and causing severe wear. Furthermore, since it is difficult to remove the bumps on each tooth surface, there is a drawback that the bending accuracy of the arm cannot be increased, and an improvement in this problem is strongly desired.

(c) Purpose of the Invention The present invention has been made to solve the above-mentioned problems, and it is possible to operate the arm while maintaining high bending accuracy, and in addition, the arm can be operated with a wide bending operation range. It is an object of the present invention to provide an industrial robot arm that has high rigidity and can also improve its load capacity.

(d) Structure of the Invention The structure of the first invention will be explained with reference to FIG. End frame material whose upper and lower parts are adjacent to one side and axis 1
A multi-jointed body is provided, which is connected by a pair of parallel links 12a, 12b parallel to 0A, and whose left and right parts are adjacent to the other side, and which is connected by other parallel links 12a, 12b. Shaft bodies 14a, 14b, 17a, 17 connected via universal joints 19a, 19b, 28a, 28b for each of 13a, 13b...
Two bendable arm bending drive shafts 1 consisting of b
4, 17 are a plurality of end frame members 13a, 13b parallel to the axis 10A at positions apart from the axis 10A.
Female threads 21 are provided longitudinally through the arm bending drive shafts 14, 17 and are threaded into male threads 21 carved concentrically with the shafts 14a, 17b at every other shaft of each of the arm bending drive shafts 14, 17. A tilting link body 16 that converts the linear motion of
7 to each other shaft body, its shaft body 14b, 1
An axial length adjustment body 18 that enables the axial expansion and contraction of the arm 7a is interposed, and the tilting link body 16 of one arm bending drive shaft 14 and the axial length adjustment body 18 of the other arm bending drive shaft 17 are connected to the same two adjacent ones. End frame material 13
a drive shaft support 15 which is arranged between a and 13b and rotatably supports the shaft bodies 14a and 17b to which the tilting link body 16 is attached, while restraining their axial displacement;
is an industrial robot arm fixed to each parallel link 12a, 12b.

Furthermore, in addition to the above configuration, the second invention includes shaft bodies 42a, 42b connected via universal joints 43a, 43b for each end frame member 13a, 13b... as shown in FIG. One bendable wrist rotation drive shaft 42 is arranged in alignment with the axis 10A, and each of its shaft bodies 42a, 42b restrains its axial displacement and is rotatable on the drive shaft support 15. This is an industrial robot arm supported by

(e) Examples Hereinafter, the present invention will be explained in detail based on examples thereof.

FIG. 3 is an overall sectional view of an industrial robot arm 10 according to an embodiment of the present invention. 12a in the figure,
12b is 1 disposed parallel to the axis 10A of the robot arm 10 within a plane including the axis 10A.
A pair of parallel links, 13a to 13d are a plurality of end frame members arranged along the axis 10A, 11 is a multi-jointed body forming the robot arm 10, and one end frame member, for example, the upper and lower parts of 13b are on one side. The end frame material 13a adjacent to the above-mentioned pair of parallel links 12a, 12
b, and the left and right parts are rotatably connected to the end frame member 13c adjacent to the other side by other parallel links 12a and 12b. In addition, since the other configuration is three-dimensionally attached to the joint body 11, it is based on FIG. I will explain.

14 and 17 are two bendable arm bending drive shafts, each having a universal joint 19a, 19b, 28.
A plurality of shaft bodies 14a, 14b, 17a, connected to each end frame member 13a, 13b via a, 28b,
17b, and a plurality of end frame members 13 are arranged parallel to the axis 10A at positions apart from the axis 10A.
a, 13b, . . .
In addition, universal joints 19a, 19b, 28a, 28b
In the illustration, the surfaces 13A of the end frame members 13a and 13b,
However, as will be described later, the drive shafts 14 and 17 expand and contract as appropriate as they operate, so if they do not come into contact with the end frame members 13a and 13b during the bending operation, the end frame members 13a and 17 It may be located out of the plane of 13b. Further, the drive shaft 14 is the axis 1
It is on a horizontal plane including 0A, and the drive shaft 17 is provided on the vertical plane, but there is no problem as long as it is not on the axis 10A.

Reference numeral 21 denotes a male screw placed in one of the shaft bodies 14a, 14b of the drive shaft 14, and in the illustration, a male screw is carved in the axial direction of the shaft body 14a, 22 is a female screw that is screwed into this male screw 21, and 23a, 23b are female screws 22. These male screws 21, female screws 22, and tilting links 23a, 23b convert the linear motion of the end frame members 13a, 13b into tilting movements of the end frame members 13a, 1.
A tilting link body 16 is configured to tilt 3b. Although not shown, this tilting link 16 is similarly attached to the shaft body 17b of the drive shaft 7. In addition, in the illustration, the arm 2 for connecting the tilting links 23a and 23b with pins is provided in one diameter direction of the female thread 22.
A guide bar 25 fixed to the drive shaft support 15 is inserted into one arm 24b of the arms 24b, and rotates when the female thread 22 moves linearly in the axial direction of the drive shaft 14. It is regulated so that it does not move. Moreover, the tilting links 23a, 23
The other end of b is parallel to tilting axes 26A and 26B, which are virtual lines connecting pins 12A and 12B and 12C and 12D of a pair of links 12a and 12b, and is connected to end frame members 13a and 13b by pins 27A and 27B. It is connected to the.

Reference numeral 18 denotes a spline-fitted shaft length adjusting body that enables the shaft body 17a of the drive shaft 7 to expand and contract in the axial direction.When the end frame members 13a and 13b are tilted by the drive shaft 14, the drive shaft 17 obstructs the movement. Although not shown, this is to prevent the drive shaft 14 from
The shaft body 14b is similarly interposed.

Reference numeral 15 denotes a drive shaft support body, which restrains the axial displacement of the shaft bodies 14a and 17b (in the figure, 14a) to which the tilting body 16 is attached, and rotatably supports them by bearings 20a and 20b. Material 13a,
A pair of parallel links 1 rotatably connecting 13b.
2a and 12b. Although two drive shaft supports 15, 15a and 15b, are shown in the drawing, only one drive shaft support body 15 may be used as long as it is designed to perform the above-mentioned function.

According to an embodiment having such a configuration, it can be operated as follows.

First, in FIG. 4, the drive shaft 14 is rotated in the direction of arrow 30 by a drive source (not shown). In addition,
In order to make the explanation of the bending motion due to the rotation of the drive shaft 14 easier to understand, the description will be made with reference to FIGS. 5a and 5b, in which the structure of the other drive shaft 17 is omitted. The rotation of the drive shaft 14 is controlled by the end frame members 13a and 1 through the universal joint 19a.
The power is transmitted to the shaft body 14a between 3b. This shaft body 14
Since the axial displacement of a is restricted by the drive shaft support 15, the male screw 21 rotates without being displaced. Therefore, the female screw 22 that engages with this moves in the direction of the arrow 31, so that the female screw 22
Tilting links 23a, 23b are displaced in the direction of arrow 32 via arms 24a, 24b protruding from. As a result, the end frame members 13a and 13b are as shown in FIG.
As shown in FIG. 2 , it tilts in the directions of arrows 33a and 33b about the tilting axes 26A and 26B. At this time, the shaft length adjusting body 18 interposed in the shaft body 17a of the drive shaft 17 (not shown) expands and contracts as appropriate, and the end frame members 13a, 13b
movement is not obstructed. By repeating such operations, the multi-jointed body 11 bends downward from the state shown in FIG. 5c within one plane as shown in FIG. 5d. At this time, by appropriately selecting the amount of rotation of the drive shaft 14, the bending angle can be set arbitrarily. In addition,
It goes without saying that if the drive shaft 14 is rotated in the opposite direction of the arrow 30, it will bend upward.

When the other drive shaft 17 is rotated by a drive source (not shown) in the direction of arrow 35 as shown in FIG. 4 while such a bending operation is being performed in one plane, the shaft body 17b The tilting link body 16 can also be bent in a direction perpendicular to the plane of the paper in FIG. 5d. At this time, the drive shaft 14, which has already been bent downward, is expanded and contracted in the axial direction by the shaft length adjusting body 18 provided on the shaft body 14b. Therefore, the robot arm 10 can be bent three-dimensionally in any direction, and the wrist 36 attached to the tip of the arm 10 can be moved to a desired position.

FIG. 6 shows a different embodiment of the invention, in which a wrist rotation drive shaft 42 is added to the arm 10 of FIG. 4. Since there is no difference in other parts, the same reference numerals are given and the explanation will be omitted.

This drive shaft 42 is arranged so as to coincide with the axis 40A of the robot arm 40, and the end frame member 1
Universal joints 43a and 43b are provided within the planes of 3a and 13b. And each shaft body 42a, 42b
is supported on the drive shaft support 15 so as to restrain its axial displacement.

Even in the embodiment with such a configuration, in addition to being able to perform the same bending operation as the robot arm 10 of the invention described above, the wrist rotation drive shaft 42
When the robot arm 40 is rotated in the direction of arrow 44, the wrist 36 can be rotated in the direction of arrow 45 in FIG. 5d while the robot arm 40 is bent in various ways.
Therefore, the wrist 36 can be rotated at any position and at any angle, and the wrist 36 can be used to perform desired tasks.

(f) Effects of the Invention As can be understood from the embodiments described in detail above, in the first invention, in the multi-jointed body of the robot arm, one or two arm bending drive shafts are rotated. The tilting link body is actuated to tilt the end frame material, and at that time, the other bending drive shaft is made extendable and retractable by its shaft length adjusting body, so that the robot arm can be bent in a desired direction and angle. and its tip can be moved to any position.

In the second invention, since the wrist rotation drive shaft is provided in the configuration of the above invention so as to coincide with the axis of the robot arm, the wrist attached to the tip can be moved to a desired position by adding the above-mentioned bending action. Desired rotation can be given, and various forms of remote work using the wrist can be adopted.

[Brief explanation of the drawing]

Figure 1 shows an example of a conventional industrial robot arm.
Fig. 2 is an explanatory diagram of its operation, Fig. 3 is an overall cross-sectional view of the industrial robot arm according to the first embodiment of the invention in its initial state, and Fig. 4 is a perspective view of the structure between two adjacent end frame members. , Fig. 5a is an initial state diagram showing only one bending drive shaft, Fig. 5b is an explanatory diagram of a state in which the end frame member is tilted, and Fig. 5c is a robot arm showing only one bending drive shaft. Initial state diagram of 5th
Figure d is a diagram of the bent state, and Figure 6 is a perspective view of the structure between two adjacent end frame members in a different embodiment of the invention. 10, 40... Robot arm, 10A, 40A
... Axis line, 11... Multi-jointed body, 12a, 12b... A pair of links, 13a, 13b... End frame material, 14, 17
...Arm bending drive shaft, 14a, 14b, 17a,
17b...Shaft body, 15...Drive shaft support body, 16...Tilt link body, 18...Shaft length adjustment body, 19a, 19b,
28a, 28b, 43a, 43b...universal joint, 2
1...Male thread, 22...Female thread, 23a, 23b...Tilt link, 42...Wrist rotation drive shaft.

Claims (1)

[Scope of Claims] 1. A plurality of end frame members are arranged along the axis of the robot arm, and the upper and lower parts of each end frame are connected to the adjacent end frame member on one side and a pair of parallel end frames parallel to the axis. A multi-jointed body is provided, which is connected by a link and whose left and right sides are adjacent to each other, and which is connected by another parallel link, and each end frame has a shaft body connected via a universal joint. two bendable arm bending drive shafts are provided extending longitudinally through the plurality of end frame members parallel to the axis at a position apart from the axis, and every other shaft of each of these arm bending drive shafts is provided with , equipped with a tilting link body that converts the linear motion of a female screw threaded into a male screw carved concentrically with the shaft body into a tilting motion of the end frame member, and each other of the arm bending drive shaft A shaft length adjusting body that enables the shaft body to expand and contract in the axial direction is interposed in the shaft body, and the tilting link body of the one arm bending drive shaft and the shaft length adjusting body of the other arm bending drive shaft are connected to two adjacent arm bending drive shafts. a drive shaft support that is disposed between two identical end frame members and rotatably supports the shaft body to which the tilting link body is attached while restraining its axial displacement, and is fixed to each of the parallel links; An industrial robot arm, characterized in that the multi-jointed body can be bent vertically and horizontally by rotation of each arm bending drive shaft. 2 A plurality of end frame members are arranged along the axis of the robot arm, and the top and bottom of each end frame member are connected to the adjacent end frame member on one side by a pair of parallel links parallel to the axis. A multi-jointed body is provided in which each end frame member is connected to the adjacent end frame member on the other side by another parallel link, and each end frame member is provided with two bendable arms each consisting of a shaft body connected via a universal joint. A drive shaft is provided longitudinally through the plurality of end frame members parallel to the axis at a position apart from the axis, and a drive shaft is provided at every other shaft of each of these arm bending drive shafts concentrically with the shaft. A tilting link body is installed that converts the linear motion of a female screw threaded into a male screw carved in a shape into a tilting motion of the end frame material, and the shaft is attached to each other shaft body of the arm bending drive shaft. An axial length adjusting body that allows the body to expand and contract in the axial direction is interposed, and the tilting link body of the one arm bending drive shaft and the axial length adjusting body of the other arm bending drive shaft are connected between two adjacent same end frame members. A drive shaft support is fixed to each of the parallel links to rotatably support the shaft body to which the tilting link body is attached while restraining its axial displacement, and for each end frame member. One bendable wrist rotation drive shaft consisting of a shaft body connected via a universal joint,
While aligning with the axis, each of the shaft bodies is rotatably supported on the drive shaft support body while restraining its axial displacement, and the multi-jointed body is bent vertically and horizontally by rotation of each arm bending drive shaft. An industrial robot arm, characterized in that the wrist attached to the distal end of the multi-jointed body can be rotated around the wrist axis by rotation of the wrist rotation drive shaft.