JPS58177290A - Manipulator - 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 The present invention relates to a manipulator that is attached to the end of an arm of an industrial robot or the like and is used to grasp and move or transfer a workpiece or the like.

In general, manipulators use a pair of clamping members that open and close by pivoting around the operating shaft to grip and release the workpiece, but the mechanism for opening and closing both clamping members is simple. The toggle method is often used because it works reliably. However, in the toggle method, the gripping force of the clamping member changes drastically when the diameter of the workpiece to be handled changes, so there are significant restrictions on the size of the workpiece, especially the outer diameter of the gripping part. It had drawbacks.

In view of the above drawbacks, the present invention uses a worm gear device for the opening/closing mechanism of the clamping member, so that the gripping force of the clamping member can always be kept constant regardless of the diameter of the workpiece, etc. It is an object of the present invention to provide a manipulator configured so that the gripping force can be easily adjusted.

Embodiments of the present invention will be described below based on the drawings. 1 is a robot arm, 2 is a mounting frame attached to the tip of arm 1, 3.4 is a sandwiching member, and 5.6 is a sandwiching member 3.4, respectively.
A segment gear fixed to the base end of both gears 5.
．． 6 is fixed to two operating shafts 7.8 that are rotatably supported parallel to the mounting frame 2, and are meshed with each other, so that when one operating shaft 7 is rotated, the other operating shaft 8 is rotated. rotates in the opposite direction, and as a result, both clamping members 3.4 rotate about the operating shafts 7.8 to open and close, respectively.

9 is a segment worm gear fixed to the operating shaft 7; 10
is a worm that meshes with the worm gear 9, and has a cylindrical shape and is spline-fitted to the spline shaft portion 12 of the rotating shaft 11 so as to be slidable in the axial direction. The rotating shaft 11 is attached to the mounting frame 2
It is connected via a sleeve contact 14 to a reversible electric motor 13 fixedly attached to the side of the body, so that the electric motor 13 can rotate it in forward and reverse directions.

Reference numeral 15 denotes a spring receiver that is loosely fitted to the rotating shaft 11 adjacent to the worm 10, and 16 supports the rotating shaft 1 with one end supported by the spring receiver 15.
The push spring 1 is fitted into the push spring 1, and 17 is an adjustment screw for adjusting the spring pressure of the push spring 16.The push spring 17 is installed in such a manner that the tip of the rotating shaft 11 is fitted into the through hole 18 drilled in the center. It is completely screwed onto the side plate 2a of the frame 2, and the push spring 16 comes into contact with the bottom of the side plate 2a through the washer 19. 10 is pressurized and held at a fixed position in contact with the end surface of the sleeve joint 14. The distal end portion of the rotating shaft 11 is rotatably supported by an adjusting screw 17 via a nylon bushing 20.

21 is a lock nut for the adjustment screw 17.

Reference numeral 22 denotes a limit switch serving as means for stopping the clamping member 3.4 on the closing side, and numeral 23 denotes a limit switch serving as means for stopping the opening side of the clamping member 3.4, both of which operate to stop the electric motor 13.

Now, the electric motor 13 operates in the forward rotation direction and the rotating shaft 11
When rotated, the worm 10 rotates in conjunction with the rotation shaft 11, and the worm gear 9 is rotated in the direction of arrow A.

Due to the rotational displacement of the worm gear 9, the segment gear 6.
Both clamping members 3 and 4, which are interlocked with each other via 6, rotate toward the closing side as shown by chain lines with the operating axis and 8 as fulcrums, and grip the workpiece W by sandwiching it from both sides. .

When the workpiece W is gripped by the two clamping members 3.4 in this manner, further rotational displacement of the two clamping members 3, 4 and the worm gear 9 is prevented. When the worm 10 continues to be rotated by the rotating shaft 11 in this state, the worm gear 9 remains stopped and the worm 10 rotates and moves against the push spring 16 in the axial direction shown by arrow B, compressing the push spring 16. At the same time, torque is applied to the worm gear 9 by the reaction force.

This torque increases the gripping force of the two clamping elements 3.4. When the spring bearing 15 moves to the position shown by the chain line as the worm 10 moves in the axial direction, the spring bearing 15 activates the limit switch 22 and the electric motor 13 is stopped. When the electric motor 13 stops, the worm 10 stops at that position due to its self-braking function, and a state in which a constant torque is applied to the worm gear 9 by the spring pressure of the compressed push spring 16 is maintained. As a result, both pinching members 3
．． 4 is applied with a predetermined gripping force, and the workpiece W is gripped with a constant gripping force. In this gripping state, the arm 1 is operated to move or transfer the workpiece W. By rotating the adjusting screw 17 and adjusting the spring pressure of the push spring 16, the gripping force applied to the clamping members 3.4 can be adjusted.

Next, when the electric motor 13 rotates in the opposite direction.

First, the worm 10 moves in the axial direction due to its rotation and the spring pressure of the push spring 16 to the fixed position shown by the solid line, and during this time both the clamping members 3.4 maintain the position in which they grip the workpiece W. There is. When the worm 10 returns to its normal position, the worm gear 9 rotates in the direction opposite to the arrow A in conjunction with the rotation of the worm 10, and in response, both the clamping members 3.4 are rotated toward the opening side. Then, the workpiece W is released. When the worm gear 9 further rotates and comes into contact with the limit switch 23 and activates it,
The electric motor 13 is stopped, and both clamping members 3.4 are stopped at a constant opening angle. Therefore, by changing the mounting position of the limit switch 23, both pinching members 3.4
The opening position can be set arbitrarily, and the opening angle of both clamping members 3° and 4 can be easily adjusted according to the thickness of the workpiece W.

Note that the mounting angle of the worm 101 rotation shaft 11 and the electric motor 13 relative to the mounting frame 2 can be changed to an inclined shape other than the orthogonal shape shown in the figure by simply changing the orientation of the worm gear 9.

The embodiment shown in FIG.
, worm gear 9 is omitted and both worm gears 25.26
Since the worm 10 is directly engaged with the worm 10 and rotated, the transmission mechanism can be further simplified. Further, this example differs from the previous example only in that an actuator 27 is provided protruding from the tip of the worm 10 to operate a limit switch 22 serving as a closing-side stop means, and the other components are the same. Parts are designated with the same number.

The spring means for pressurizing and holding the worm 10 in a fixed position on the rotating shaft 11 may be a plurality of stacked disc springs or a compression spring instead of the helical spring 16 of each of the above embodiments. It is also possible to use rubber.

As described above, the manipulator of the present invention uses a worm gear device for the opening/closing mechanism of the clamping member, and includes a worm gear fixed to the operating shaft of the clamping member, a worm that meshes with the worm gear, and a worm gear that is connected to the clamping member. The clamping member is configured to open and close by applying rotational torque to the operating shaft of the clamping member, and includes a spring pressure means for pressurizing and holding the worm at a fixed position on the rotating shaft to which the worm is slidably fitted in the axial direction. After the clamping member rotates toward the closing side in conjunction with the rotation of the worm and grips the workpiece, the worm further moves in the axial direction against the spring pressure means to Since the operating shaft is configured to have a constant torque, the gripping force of the clamping member can always be kept constant regardless of the diameter of the object to be handled, such as a workpiece. Moreover, there is an advantage that the gripping force can be easily varied by adjusting the spring pressure of the spring pressure means.

Furthermore, since the worm gear device itself that opens and closes both the sandwiching members has a deceleration function, there is no need to incorporate a deceleration mechanism into the rotary drive device that rotates the worm. Furthermore, the opening angle of the clamping member can be arbitrarily adjusted by simply changing the rotation angle of the worm gear, which has various advantages in that it can be changed over a wide range.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional front view of main parts showing one embodiment of the present invention;
The figure is a longitudinal sectional front view of a main part of another embodiment.

Claims (1)

[Claims] 1. A worm gear fixed to the operating shaft of the clamping member, a worm that meshes with the worm gear, and a rotating shaft that the worm engages with the Nupline so as to be slidable in the axial direction, in the forward and reverse directions. a driving device, a spring pressure means for pressurizing and holding the worm at a fixed position on the rotating shaft, and the clamping member rotates toward the closing side in conjunction with the rotation of the worm to remove liquid from the workpiece, etc. and a closing-side stop that stops the rotary drive device when the worm moves in the axial direction against the spring pressure means until a constant torque is applied to the operating shaft via the worm gear. and an opening side stopping means that stops the rotational drive device when the clamping member rotates by a certain angle toward the opening side in conjunction with the rotation of the worm. 2. The manipulator according to claim 1, wherein the spring pressure of the spring pressure means is adjustable. 6. The manipulator according to claim 1 or 2, wherein the rotation angle of the clamping member toward the opening side is adjustable.