JPH05245787A - Wrist rocker of manipulator - Google Patents

Abstract

PURPOSE:To articulate a wrist member rockably to an omnibearing around the axis of an article gripping member of a manipulator and facilitate a job for article assembling work as well as to curtail the operating kinetic space of a number of connecting arms of the manipulator. CONSTITUTION:Three ring circular grooves 5A-5C being solidly crossed with one another are installed in the periphery of a connecting joint part of a wrist member 5, while three recess parts 6A-6C are installed in the inner circumference of a connecting joint part of an article gripping member 6 at equi-interval, and each of balls 7A-7C is held between the circular groove and the recess, and the wrist member is rotated, whereby the article gripping member is rocked in an omnibearing around the axis of the wrist member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for handling articles by manipulating a manipulator, and particularly for assembling articles.

[0002]

2. Description of the Related Art In a conventional manipulator, a plurality of arms are articulated in series, each joint is made a single motion, and a single motion is performed by each joint. The members are interlockingly connected so that the members move.

[0003]

Therefore, when causing the article gripping member to perform a swinging motion in any radial direction with respect to the axis of the wrist member, a joint that makes a bending motion in the X direction and a Y joint.
Since it must be realized by stacking at least two articulations with the articulating articulation, it is necessary to connect the articulating arm in the X direction at one end and in the Y direction at the other end. As a result, there is a drawback that the number of joints increases, the joint movement of each arm of the manipulator becomes complicated, and the structure of the manipulator becomes large.

[0004]

SUMMARY OF THE INVENTION Therefore, according to the present invention, an omnidirectional oscillating motion is made possible by one joint, and an article gripping member having a manipulator gripping tool and the gripping member are supported. In the joint joint portion with the wrist member, a plurality of circular arc grooves that intersect three-dimensionally with each other on the outer circumference of the cylindrical joint portion of the wrist member are circumferentially recessed with different arc diameters, An annular retainer, through which a long window is formed, which holds balls having a diameter for fitting and rolling at equal intervals in the circumferential direction and holds the balls movably in the axial direction, is externally fitted to the wrist member cylindrical joint portion. A plurality of recesses are provided on the same circumference of the inner circumference of the cylindrical joint of the gripping member so as to sandwich the balls held at the equal intervals between the balls and the circular arc groove.

[0005]

When the joint cylinder end portion of the wrist member, that is, the joint joint portion with the article gripping member is rotated, the balls are held at the circumferential interval by the recess of the article gripping member. At the same time as being guided in the circular arc groove on the outer circumference of the cylinder end, it moves vertically along the long window of the retainer in the axial direction. Therefore, the article gripping member holding the ball in the recess is
Since the plurality of arcuate grooves intersect with each other, the arcuate grooves swing in all directions around the rotation axis of the wrist member. The plurality of circular arc grooves have different circular arc diameters, and the plurality of balls not only have the diameters to fit and roll into the respective circular arc grooves, but also the respective circular arc grooves are solid at the intersection points of the plural circular arc grooves. Since they are crossed, there is no risk that the rolling ball will stray into another circular arc groove.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the manipulator illustrated in FIG. 1, one ends of parallel links 2A and 2B are rotatably supported on the top of a column 1, and the parallel links 2A and 2B are lifted and lowered by a motor M, and the parallel link is moved. At the other ends of 2A and 2B, a horizontal end portion of an inverted L-shaped arm member 3 is horizontally rotatably supported, and at a vertical lower end portion of the L-shaped arm member 3, a swivel base 4 is fixedly mounted. An article holding member 6 is rotatably fitted on a wrist member 5 rotatably supported by 4 via a ball described later to form a joint connecting portion. Then, the article A is grasped by a grasping tool (not shown) attached to the grasping member 6. The article B is an article that is placed on the work table T and on which the article A is assembled.

First, a detailed embodiment of the joint joint between the wrist member 5 and the article gripping member 6 of the present invention will be described with reference to FIGS.
0, the outer circumference of the joint cylinder end of the wrist member 5 joined to the swivel 4 by the flange portion has a plurality of, for example, three annular arc grooves 5A, 5B and 5C as shown in FIG. 3 (A). These arcuate grooves 5A, 5B and 5 are recessed.
When C is developed on a plane, as shown in FIG. 3 (B), the first circular arc groove 5A is on the circumference, and the second circular arc groove 5B and the third circular arc groove 5C are out of phase with an undulation of 120 °. As shown in FIG. 4, not only the circular arc diameters of the circular arc grooves 5A, 5 and 5C are three-dimensionally intersected with one circular arc groove 5A, but also the circular arcs from the cylinder center XX (see FIG. 2) of the wrist member. The center positions are also different, and therefore the respective arcuate grooves 5A, 5B and 5
C crosses three-dimensionally at each intersection, and each arc groove 5
Balls 7A and 7B which are fitted and rolled into A, 5B and 5C
The diameters of 7C and 7C are also different from the above-mentioned arc diameter.

Then, these balls 7A, 7B and 7C are arranged between the respective arc grooves 5A, 5B and 5C in FIG.
As shown in FIG. 3, holding recesses 6A, 6B, 6C are provided on the circumference of the inner peripheral surface of the article holding member 6 at regular intervals. That is, as shown in FIGS. 5 (A) and 5 (B), the article holding member 6 has a plurality of axial slits 8 and 8--cut into it, and the slits 8 and 8-- 7A, 7B,
7C is provided with elasticity that expands when it is sandwiched between the circular arc grooves 5A, 5B, and 5C, and after the balls are sandwiched, the nut is formed on the threaded portion 9 engraved on the outer periphery of the cylindrical portion having the slit. 1
0 (see FIG. 2) is screwed to prevent the slit from expanding, and the ball is moved between the circular arc grooves 5A, 5B and 5C of the wrist member 5 and the recesses 6A, 6B and 6C of the article holding member 6. Hold securely. Further, as is apparent from FIGS. 5A and 5B, the recesses 6A, 6B, 6C of the article holding member have some play in the circumferential direction with respect to the ball. This is for adjusting the ball-to-ball distance with respect to the relative angular deviation between the article holding member and the wrist member.

Further, on the outer circumference of the joint cylindrical portion of the wrist member 5,
The retainer 11 shown in FIG. 6 is externally fitted (see FIG. 2), and the retainer 11 is provided with axial long windows 11A, 11B and 11C, and the long windows 11A, 11B and 11C are the balls 7.
A, 7B, and 7C are allowed to move in the axial direction while being held in the circumferential direction at substantially equal intervals while being guided by the ups and downs of the arcuate groove. Therefore, by rotating the wrist member 5 and the article gripping member 6 relative to each other, the balls 7A, 7B, 7C fitted and held in the inner peripheral concave portions 6A, 6B, 6C of the article gripping member 6 are Since each of the fitting circular arc grooves 5A, 5B, and 5C shown in FIG. 4 is guided by rolling, the article gripping member 6 swings around the axis XX of the wrist member 5, and the swinging mode is as follows. It can be optionally set by the undulation degree, phase difference, etc. of the circular arc grooves 5A, 5B, 5C.

Therefore, as shown in FIG. 7, the operation levers L1 and L2 are provided on the wrist member 5 and the article gripping member 6, respectively.
When one is fixed and the one operation lever L1 is horizontally rotated and the other operation lever L2 is stationary, the article holding member 6 tilts to a desired posture according to the rotation angle of the operation lever L1. Therefore, for example, as shown in FIGS. 8 (A) and 8 (B),
When the round bar A is fitted into the hole B ′ of the article B and the clearance between the outer diameter of the round bar A and the inner diameter of the hole B ′ is extremely small,
It is difficult to insert the round bar A into the hole B in the vertical posture, but as shown in FIG. 8A, the operation lever L1 is horizontally rotated to tilt the article gripping member 6 slightly. A part of the peripheral surface of the lower end portion of the round bar A is brought into contact with the opening edge of the hole B ′, and the round bar A is gradually made upright with the opening edge as a guide, so that the round bar is easily rounded as shown in FIG. 8B. The rod A can be inserted into the hole B '. Moreover, even when a relative assembling angle shift or the like occurs between the assembled articles, the positional deviation can be absorbed by tilting the article gripping member 6 with respect to the wrist member 5. The detector S attached to the operating lever L2, when an upward force is applied to the lever L2, drives the lifting motor M shown in FIG. 1 to rotate the parallel links 2A and 2B upward to the chain line position. , The lever L2
When a downward force is applied to, the ascending / descending motor M is driven to rotate the parallel links 2A and 2B downward to the solid line positions.

FIG. 9 shows a motor M1 mounted on a swivel base 4 in place of the operating lever L1 shown in FIG. 7, and the rotation of the motor M1 is transmitted to the article gripping member 6 via a belt and a universal joint 12. However, the operating lever L2 of the member 6
If the motor is manually held in a rotation-prevented state, the motor M
1 revolves around the axis XX, and as a result, the wrist member 5
Is rotated with respect to the article holding member 6, the operation lever L
1 becomes unnecessary. FIG. 10 shows the operating lever L2 in FIG.
In place of the above, by positively rotating the wrist member 5 with the motor M2, the rotation of the article holding member 6 is suppressed and only the swing is applied. At that time, the article holding member is provided. External force such as frictional resistance is required to prevent the wrist member 5 from rotating with the wrist member 5.

[0012]

According to the present invention, since the article gripping member is swingably connected to the wrist joint portion of the manipulator along a desired trajectory, the article gripping member is attached to the wrist member around the axis of the wrist member. Since it is possible to swing in all directions, it is possible to control the grasped article to a desired tilting posture, and in the assembling work of the grasped article, etc. Compared to the case of a conventional manipulator that achieves a desired motion by stacking and accelerating a single motion, the motion space required for operating each arm member can be significantly reduced, and
When assembling the article held by the manipulator to the article on the assembly work table, the arm member of the manipulator is displaced due to bending caused by the weight of the suspended article, etc. The correction operation can be performed easily and easily.

[Brief description of drawings]

[Figure 1] Manipulator explanatory diagram

FIG. 2 is an enlarged cross-sectional view of a joint joint between a wrist member and an article gripping member.

FIG. 3A is a front view showing a right half portion of a wrist member in a cross section, and FIG. 3B is a development view of a plurality of arc grooves recessed on an outer peripheral surface of the wrist member.

FIG. 4 is an enlarged explanatory view of a main part showing a state of three-dimensional intersection at the intersection of each arc groove.

5A is a front sectional view of an article gripping member, and FIG. 5B is a plan view of FIG. 5A.

FIG. 6 is a plan sectional view of a retainer.

FIG. 7 is an operation explanatory view of the first embodiment of the present invention.

8A is a pin insertion guide explanatory diagram, and FIG. 8B is a pin insertion explanatory diagram.

FIG. 9 is an operation explanatory view of the second embodiment of the present invention.

FIG. 10 is an operation explanatory view of the third embodiment of the present invention.

[Explanation of symbols]

 4 swivel base 5 wrist member 5A to 5C annular arc groove 6 article gripping member 6A to 6C recessed portion 7A to 7C ball 11 retainer 11A to 11C long window

Claims (1)

[Claims] 1. A manipulator in which an article gripping member having a gripping tool and a wrist member supporting the gripping member are articulated to each other, and a plurality of circular arc grooves that intersect each other three-dimensionally are formed on the outer circumference of the joint cylindrical end of the wrist member. Each of the arcs has a different diameter, and is recessed in the circumferential direction. Balls having diameters that fit and roll in the respective arc grooves are held at equal intervals in the circumferential direction and the balls are moved in the axial direction. An annular retainer that penetrates through a long window that can be held is externally fitted to the end of the joint cylinder of the wrist member, and is held at the equal intervals on the same circumference of the inner circumference of the end of the joint cylinder of the gripping member. A plurality of recesses for sandwiching the ball of each of the balls with the respective arcuate grooves, and the grip member is moved to the wrist member by relative rotation of the joint inner peripheral surface of the grip member and the joint outer peripheral surface of the wrist member. A manipulator wrist rocker that rocks against.