JPS6130874B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-jointed manipulator in which all degrees of freedom are rotational.

Conventionally, the degree of freedom structure of a multi-jointed manipulator is such that all degrees of freedom are rotational, as shown in FIG. In this figure, 1 is a fixed end of the manipulator, 2 is a rotating shaft that has rotational freedom in the vertical direction with respect to the fixed end 1, and 3 is a first arm fixed horizontally to the rotating shaft 2. , 4 is a rotating shaft having a degree of freedom of rotation in the horizontal direction with respect to the first arm 3; 5 is a second arm fixed in a direction perpendicular to the axial direction of the rotating shaft 4; A counterbalance 6 is attached to 5a, and a bearing 7 is attached to the other end 5b. Reference numeral 8 indicates a rotating shaft having a degree of freedom of rotation in the horizontal direction with respect to the bearing 7, and 9 indicates a third arm fixed at right angles to the axial direction of the rotating shaft 8. A counterbalance 10 is attached to one end side 9a of the third arm.
is attached, and the other end side 9b serves as a tip portion 11 to which a hand portion or wrist portion (not shown) is attached.

By the way, in the above manipulator, the load on the actuator for driving the second arm 5 is large. In other words, the actuator of the second arm 5 drives the weight of the second arm 5 and the third arm 9, so the second arm 5 has a particularly large counterbalance 6. There were some flaws that needed to be fixed.

This invention was made to eliminate the above-mentioned drawbacks, and provides a manipulator that can significantly reduce the load on the actuator by simply attaching a counterbalance to the arm at the tip of the actuator. be. This invention will be explained below.

FIG. 2 is a configuration diagram showing an embodiment of this invention.
Reference numeral 21 indicates a fixed end of the manipulator, 22 indicates a rotating shaft having rotational freedom in a direction perpendicular to the fixed end 21, and 23 indicates a first arm, one end of which is 23a.
is formed integrally with an axis that is different from the axis of the rotating shaft 22, that is, horizontally, diagonally upward, or diagonally downward with respect to the axial direction, and the other end side 23b
A bearing 24 is fixed. 25 is the bearing 2
4, a rotating shaft having the same axial center as the axial direction of the first arm 23 and having a degree of rotational freedom in the axial direction;
26 is a second arm fixed at right angles to the axial direction of the rotating shaft 25; 27 is the second arm 2;
a rotating shaft having a rotational degree of freedom in the axial direction of 6;
A third arm 28 is fixed integrally at right angles to the axial direction of the rotating shaft 27, and is formed so as to pass near the rotating shaft 25 in the axial direction.
A counterbalance 29 is attached to the third arm 8a so that the center of gravity of the third arm 28 is near the rotation axis 27, and the other end 28b is a distal end portion to which a hand portion and a wrist portion (not shown) are attached. 3
It is 0.

Next, the operation will be explained. first arm 23
is rotated as shown by arrow A with respect to the vertical direction of the fixed end 21, and the rotating shaft 25 is rotated as shown with arrow B with respect to its axis, and the second arm 2 integrated therewith is
6, and then move the third arm 28 in the direction of arrow C.
Rotate it like this. By appropriately combining these rotations, the tip 30 of the third arm 28 can be set at a desired position in three-dimensional space.

As explained above, in the present invention, one end of the first arm is free to rotate in the vertical direction, and the second arm is arranged at the other end of the first arm so that the axes of both arms are coaxial. In addition, the second arm is provided with a third arm that rotates around a rotation axis perpendicular to the axis of the second arm, and a counterbalance is attached to this third arm. Since there is no need to attach a counterbalance to the arm of the actuator, the overall weight is reduced, and the load on the actuator can be significantly reduced, which has the advantage of requiring only a small driving force.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a conventional multi-joint manipulator, and FIG. 2 is a block diagram showing an embodiment of the present invention. In the figure, 21 is a fixed end, 22 is a rotating shaft, 23 is a first arm, 24 is a bearing, 25 is a rotating shaft, 26 is a second arm, 27 is a rotating shaft, 28 is a third arm, and 29 is a rotating shaft. Counterbalance, 30 is the tip.

Claims (1)

[Claims] 1. One end side has a degree of freedom of rotation around a first axis in the vertical direction of the fixed end, and a portion extending from the one end side to the other end side is along a second axis inclined from the first axis. A first arm that extends and whose other end is rotatable around the second axis is provided, and a third arm that is perpendicular to the second axis is provided at the other end of the first arm. a second arm having an axis of A manipulator characterized by having a.