JPH0369673B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a workpiece gripping hand used in an industrial robot or the like, and particularly to a hand for gripping a cylindrical workpiece.

[Conventional technology]

Industrial robots are commonly used as labor-saving devices that are used in conjunction with machine tools to carry in workpieces, remove finished products, and carry them out. Among these industrial robots, industrial robots that are configured to grip the inner surface of the workpiece in order to prevent scratches on the outer surface of the workpiece when gripping the workpiece are able to grip the inner surface of the workpiece within the limited space of the inner surface of the workpiece. Grasping and releasing operations must be performed with the hand. For this reason, it is difficult to grip workpieces of different sizes with one hand, and robots having hands suitable for each workpiece are used individually.

[Problem that the invention seeks to solve]

However, since such conventional industrial robots perform grasping and releasing operations with their hands in a limited space, robots with dedicated hands are used for workpieces of different sizes. When changing the model, the robot had to be changed as well, resulting in poor work efficiency. In addition, it is difficult to configure a single robot to perform gripping operations for multiple types of robots, and multiple robots must be used in process lines that handle multiple types of robots, resulting in large process lines. There were problems such as getting used to it.

In view of the above-mentioned points, the present invention aims to provide a robot gripping mechanism for gripping a cylindrical workpiece from the inside, which is capable of gripping small-diameter and large-diameter workpieces with a single robot. purpose.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention includes a shaft 20a that is provided to be able to reciprocate at least in a linear direction with respect to the robot body 7, and a shaft 20a that is provided at one end of the shaft to drive the reciprocating motion of the shaft. The first cylinder 1 is connected to the other end of the shaft so as to reciprocate together with the shaft, and a small diameter hand 15 is provided at the tip thereof, and the small diameter hand is opened and closed by reciprocating motion in the axial direction. an arm 17 incorporating a taper shaft 16 and a second cylinder 1b for driving its reciprocating motion; a large-diameter hand 12 that is attached to the outer circumferential side of the arm and is driven to open and close by the reciprocating motion of the arm; It is characterized by having the following.

[Effect]

In the present invention, by opening and closing the large-diameter hand using the first cylinder, it is possible to grasp and release a large-diameter workpiece, and by opening and closing the small-diameter hand using the second cylinder, it is possible to grasp and release a small-diameter workpiece. Can be grasped and released.

〔Example〕

1 to 6 are configuration diagrams showing embodiments of the present invention. Fig. 1 is a fragmented sectional view of a gripping mechanism of a robot according to an embodiment of the present invention, Fig. 2 is a sectional view taken along the line A-A in Fig. 1, and Fig. 3 shows a state in which the arm is removed. FIG.

In FIGS. 1 to 3, the gripping mechanism attached to the robot body 7 is rotated in both directions indicated by the arrow The arm 17 is rotated in both directions indicated by arrow Y.

A small-diameter hand 15 is provided at the tip of the arm 17, and a taper shaft 16 is provided so as to contact the inner surface of the small-diameter hand 15. Taper shaft 16 is connected to shaft 20c. The shaft 20c is a cylinder 1b built into the arm 17.
The shaft is connected to the piston, and a spring 2b is engaged with the shaft. A fluid supply path 19 passing through the arm 17 from the cylinder 1b is provided,
This fluid supply path 19 is configured to be connected to a supply path from the fluid supply port 3b when the arm 17 and arm support portion 9 are connected. Another large diameter hand 12 of the arm 17 is connected to the arm 17 by a lever 13 and engaged with the upper and lower blocks 10 by a cam follower 11. The upper and lower blocks 10 move in the axial direction on the surface of the arm 17,
The spring 2c of the push-up pin 14 always pushes it up toward the arm support portion 9 side. The arm 17 is connected to the arm support 9 by a retractable head 18 hooked on a shaft 20b of a cylinder 1a built into the arm support 9. The stopper stand 8 is fixedly connected to the rotating mechanism section 5. Arm support portion 9 is connected to shaft 20a. The shaft 20a connects to the shaft 20 of the cylinder 1 via the ball 4.
connected to. The shaft 20a is interposed between the shafts 20 and 20a by the bevel gears 6 and 6a.
This is to prevent the seal of cylinder 1 from being affected by the rotation of the shaft when the shaft rotates, and semicircular grooves are machined on the shaft 20 and shaft 20a, and several balls 4 are inserted between them to prevent rotation. Shaft 2
I'm trying not to get it to 0.

The operation of each part is explained in Figures 4 to 6.
This will be explained using figures. FIG. 4 is a partially exploded cross-sectional view showing the opening and closing operation of the large-diameter hand, in which (a) shows the workpiece being released, and (b) the workpiece gripping state.

In FIG. 4, when the shaft 20 of the cylinder 1 is pushed down by the pressure of the fluid supplied from the fluid supply port 3, the shaft 2 connected to the shaft 20
0a, the arm support portion 9, and the arm 17 are also pushed down. At this time, the stopper stand 8 is rotated by the rotating mechanism section 5.
It is fixedly connected and its position does not change. The upper and lower block 10 is pushed up by the push-up pin 14 and the spring 2c and is in contact with the stopper stand 8. Therefore, the distance between the cam follower 11 engaged with the upper and lower blocks 10 and the lever 13 is relatively widened, so that the large-diameter hand 12 is in a closed state and the workpiece 21 is released.

When the fluid supply is stopped, the shafts 20, 20a, arm support 9, and arm 17 are returned to their original positions by the reaction force of the spring 2, and the push-up pin 14 and spring 2c are moved by the upper and lower blocks 10 held by the stopper stand 8. Being pushed down. At this time, the cam follower 11 engaged with the upper and lower blocks 10
Since the distance between the lever 13 and the lever 13 becomes relatively narrow, the large-diameter hand 12 is in an open state and grips the workpiece 21.

FIG. 5 is a partially exploded sectional view showing the opening and closing operation of the small-diameter hand, in which (a) shows the workpiece being released, and (b) the workpiece gripping state.

In FIG. 5, when the shaft 20c of the cylinder 1b is pushed down by the pressure of the fluid supplied from the fluid supply path 19, the taper shaft 16 connected to the shaft 20c is also pushed down. The tapered shaft 16 has a front end face that is thicker than the rear end face connected to the shaft 20c. The small diameter hand 15 is provided with a through hole through which a shaft 20c connected to the arm 17 can be inserted and removed. A slit is provided in a portion protruding from the arm 17 so as to be pushed outward.

The small diameter hand 1 is lowered by lowering the taper shaft 6.
Since the portion in contact with the shaft 20c has approximately the same diameter as the shaft 20c, the small diameter hand 15 is in a closed state and releases the workpiece 21a.

When the fluid supply is stopped, the shaft 20c and the taper shaft 16 are moved by the reaction force of the spring 2b.
is raised and returned to its original position. At this time, since the taper shaft 16 that contacts the small-diameter hand 15 is a thick portion, the small-diameter hand 15 is pushed out and into an open state, and grips the workpiece 21a.

In this way, the hands in Figures 4 and 5 are in a closed state when fluid is being supplied, and are in an open state when fluid supply is stopped, so even if fluid is not supplied due to some abnormality when gripping a workpiece, the hand can still be gripped. Workpieces will not fall.

FIG. 6 is a partially exploded cross-sectional view showing the arm attachment/detachment operation, showing the ear arm in a fitted state, and (b) showing the arm in a detached state.

In FIG. 6, the cylinder 1a is the fluid supply port 3.
The shaft 20b is pushed down by the pressure of the fluid supplied from a, and when the fluid supply is stopped, the spring 2
The shaft 20b rises due to the reaction force of a. The shaft 20b has a recessed portion at its tip into which the retracting head 18 can be inserted, and a ball 4a is incorporated into the side surface of this recessed portion. The arm support portion 9 is provided with a first hole having the same diameter as the shaft 20b up to the position when the shaft 20b is raised, and a second hole with a somewhat larger diameter is provided at the lower end of this first hole. Further, a third hole into which the arm 17 can be fitted is provided at the lower end. To remove the arm 17, push down the shaft 20b with the pressure of the fluid. The tip of the shaft 20b will reach the second hole with a larger diameter, and the balls 4a will move radially, removing the protrusion that was locking the retracting head 19. It disappears and comes off. When installing, the reverse operation is performed. and arm 17
After installing the shaft 2 due to the reaction force of the spring 2a.
0b rises and the lower end of the shaft 20b returns to the first hole having the same diameter, so the ball 4a moves inward and the retraction head 18 is hooked by its protrusion. Since the arm is removable in this way, it can be easily replaced with a hand that matches the diameter of the work to be gripped.

〔Effect of the invention〕

According to the present invention as described above, a small-diameter hand is provided at the tip of the arm, and a large-diameter hand is provided on the outer periphery, making it possible to handle various types of small-diameter and large-diameter workpieces with one machine. The process line can be downsized and it becomes easier to deal with model changes.

[Brief explanation of drawings]

FIG. 1 is a fragmented sectional view of a gripping mechanism of a robot according to an embodiment of the present invention, and FIG.
3 is a perspective view with the arm removed, FIG. 4 is a partially fragmented sectional view showing the opening/closing operation of the large-diameter hand, and FIG. 5 is a section showing the opening/closing operation of the small-diameter hand. Fig. 6 is a partially broken sectional view showing the operation of attaching and detaching the arm. 9...Arm support part, 12...Large diameter hand,
15...Small diameter hand, 17...Arm, 20,
20a, 20b, 20c...Shaft.

Claims (1)

[Claims] 1. In a gripping mechanism of a robot for gripping a cylindrical workpiece from the inside, a shaft is provided to be capable of reciprocating at least in a linear direction with respect to the robot body, and one end of the shaft is provided with a reciprocating movement of the shaft. A first cylinder for driving, and a small diameter hand connected to the other end of the shaft so as to reciprocate together with the shaft, and a small diameter hand is provided at the tip, and the small diameter hand is opened and closed by reciprocating motion in the axial direction. an arm having a built-in second cylinder for driving the reciprocating movement of the tapered shaft; and a large-diameter hand that is attached to the outer circumferential side of the arm and is driven to open and close by the reciprocating movement of the arm. A gripping mechanism for a robot characterized by the following.