JPH03196985A - hand device - Google Patents

Abstract

PURPOSE:To lower a work around a shaft only with its own weight as well as to eliminate the occurrence of dust in reducing the extent of friction with the shaft by transferring the work held on a work holder onto a supporting claw of a work supporting device once, and constituting it so as to be inserted into the shaft in the state intact. CONSTITUTION:When a work (spacer) W is inserted into a shaft B, first of all, a controlled body 1 moves downward, a work holder 17 attracts the work at the lower end or grasps it for retention. In the state intact, the work holder goes up and, after it is positioned at an up end position, the controlled body is moved upward the shaft. Next, after a supporting claw 26b of each work supporting device 26 advances toward a lower position of the work, work holding by the work holder is released, through which the work is mounted on the supporting claw of each work supporting device for retention. Afterward, the controlled body moves downward and centering for each shaft of a hand body and the work holder is carried out by a centering device 12, thus the work is inserted thereinto around the shaft with its own weight.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a hand device used for automatically inserting a workpiece having a center hole, such as a spacer, around a shaft.

(Prior Art) As a hand device for automatic insertion of this type of workpiece, conventionally, an electromagnet for magnetic attraction, a suction cup for vacuum attraction, a gripping claw for grasping the workpiece, etc. are attached to a controlled object such as an arm of an industrial robot. Generally, a shaft is equipped with a workpiece holder, and the workpiece sucked or gripped by the workpiece holder is forcibly inserted into the shaft.

(Problem to be Solved by the Invention) However, with the above-mentioned conventional method, when the workpiece is automatically inserted, if the workpiece suction position or grasping position by the workpiece holder deviates from the proper position, or if the positioning of the controlled object If there is an error in accuracy, it is difficult to align the center of the workpiece with the axis of the shaft. Insertion in this mismatched state causes so-called strong contact between the shaft and the workpiece during insertion, and dust due to abrasion powder and the like is generated accordingly. Therefore, the above-mentioned conventional hand device cannot be used particularly in places where cleanliness of the air is required, such as clean rooms used in the field of manufacturing semiconductors and the like.

The present invention has been made in view of the above, and an object of the present invention is to automatically insert the workpiece into the shaft without making strong contact with the shaft. Reduce dust generation as much as possible due to
To enable a hand device to be used without any trouble in a clean room or the like.

(Means for Solving the Problem) In order to achieve the above object, in the invention according to claim (1), a support claw for supporting the workpiece is made to protrude below the workpiece sucked or gripped by the workpiece holder. By replacing the workpiece holder with support by support claws and inserting the workpiece in that state, the workpiece can be inserted into the shaft by applying only its own weight.

That is, in the present invention, a controlled body movable in at least two dimensions including up and down by a robot or the like, a hand body supported by the controlled body so as to be movable in a horizontal direction via a floating mechanism, and a hand main body that is movable in a horizontal direction via a floating mechanism. A pair of shaft centering tools supported by the main body so as to be movable in the vertical direction and biased to protrude downward; a workpiece holder that holds a workpiece by suction or grip; and at least three workpiece supports attached to the hand body on the outer peripheral side of the workpiece holder at equal angular intervals concentrically with the centering tool. Each of the workpiece supporting devices has a support claw that moves forward and backward relative to a position below the workpiece held by the workpiece holder when the workpiece holder is at the ascending end position.

(Function) With the above configuration, in the invention according to claim (1), when a workpiece is inserted into the shaft, the controlled body first moves downward, and the workpiece holder attracts the workpiece at its lower end. Grab and hold. In this state, the workpiece holder rises and is positioned at the rising end position, and then the controlled body moves upward on the shaft. Next, after the support claws of each workpiece support device move forward to a position below the workpiece, the workpiece holding by the workpiece holder is released, whereby the workpiece is held on top of the support claws of the workpiece support device. Thereafter, the controlled body moves downward, and the centering tool aligns the hand body and the workpiece holder with respect to the shaft, and as the controlled body moves downward, the workpiece is inserted around the shaft. At this time, since the workpiece is supported by the support claws of the workpiece support device, it descends only by its own weight and is inserted around the shaft. When the workpiece reaches a predetermined position around the shaft, the support claws of each of the workpiece support devices move backward, and the workpiece is dropped and held at the predetermined position.

Therefore, in this case, when the workpiece is inserted into the shaft, it descends only by its own weight and is inserted around the shaft, so the workpiece is inserted into the shaft without strong contact.
The frictional resistance between the workpiece and the shaft is small, so the generation of dust, etc. can be reduced as much as possible.

(Example) Embodiments of the present invention will be described below based on the drawings.

1 to 3 show the overall configuration of a hand device A according to an embodiment of the present invention. This hand device A is shown in FIGS. 2 and 3.
As shown in the figure, this is for inserting a ring-shaped spacer W as a workpiece having a center hole W1 into a shaft B having an axis in the vertical direction.The upper part of the shaft B has a large diameter spacer insertion part. B1 and a small-diameter bearing fitting part B2 concentrically continuous above the spacer insertion part B1 are formed. Further, a bearing fitting groove B3 is formed on the outer periphery of the bearing fitting part B2, and a spacer insertion part B3 is formed in this fitting groove B3.
A bearing C having an outer diameter smaller than 1 is fitted.

Then, the spacer W (work) is inserted into the outer periphery of the spacer insertion portion B1 from above the shaft B while letting the bearing C slide under it.

In FIGS. 1 to 3, reference numeral 1 denotes a controlled body movable in three-dimensional directions, horizontally and vertically, which is attached, for example, to the tip of an arm of an industrial robot (not shown). A hand main body 3 is suspended and supported by the controlled object 1 via a floating mechanism 2 so as to be movable in the horizontal direction. This hand body 3 has an upper part 4 in the shape of a cylinder with a bottom that is open upward, and a cylindrical part 4a that hangs integrally from the bottom of the upper part 4.The upper end of the hand body 3 is concentrically and integrally connected to the upper part 4. and a bottomed cylindrical lower part 5 that is open upward, and a flange 4b that extends outward in the radial direction at the upper end of the upper part 4.
is formed, and the hand main body 3 is attached to the floating mechanism 2 at this flange 4b.

An air cylinder 6 for biasing the centering tool having a vertical cylinder axis is attached to the inner bottom surface of the upper part 4 of the hand main body 3, and the piston rod 6a of this cylinder 6 is attached to the bottom wall of the upper part 4. The rod is inserted through a rod insertion hole 7 formed therethrough and extends downward (into the cylindrical portion 4a). A center hole 8 is formed through the center of the bottom wall of the lower part 5, and a slider device 9 made of a ball spline is attached to the center hole 8. This slider device 9 is
Spline nut 9a bolted to the bottom wall of the lower part 5
The piston rod 6a of the cylinder 6 is slidably but non-rotatably inserted into and supported by the spline nut 9a.
The upper end of the spline shaft 9b is connected to the lower end of the piston rod 6a of the cylinder 6 via a joint 11, and the lower end of the spline shaft 9b is connected to the lλ land. A cylindrical centering tool 12 having approximately the same diameter as the bottom wall of the lower part 5 of the main body 3 is fastened and fixed. Therefore, the centering tool 12 is the slider device 9.
It is supported so as to be able to move up and down relative to the hand body 3, and is constantly urged downward by the expansion pressure of the cylinder 6.

A two-stage recess 13 is formed on the lower surface of the centering tool 12, and by fitting the bearing C of the shaft B into the lower step 13a of the recess 13, the hand body 3 is attached to the shaft B. Also, a workpiece holder 17, which will be described later, is centered.

Further, a sensor mounting hole 14 is formed in the peripheral edge of the centering tool 12 and extends vertically through the sensor mounting hole 14, and the bottom of this mounting hole 14 is opened at the upper surface of the lower step 13a of the recess 13. Further, a capacitance type hide sensor 15 is attached to the sensor attachment hole 14 .

The hide sensor 15 detects when the bearing C of the shaft B is completely fitted into the lower step 13a of the recess 13 and outputs a signal. The signal line of this hide sensor 15 is connected to the lower part 5 of the hand main body 3.
It is inserted into a protective tube 16 that slidably penetrates the bottom wall, the cylindrical portion 4a of the upper part 4, and the bottom wall.

Around the centering tool 12, the lower end surface is a work suction surface 18.
A work holder 17 having a substantially cylindrical shape is disposed concentrically with the centering tool 12. That is, this work holder 1
7 has a center hole 19, and the centering tool 12 (bottom wall of the lower part 5 of the hand main body 3) is disposed in the center hole 19. At the upper end of the workpiece holder 17, guide rods 20, 20. The lower end of ... is attached and fixed. Each of the guide rods 20 slidably passes through the upper side portion 4 of the hand main body 3, the bottom wall or the cylindrical portion 4a, and its upper end is fixed to a ring 21 disposed around the air cylinder 6. guide rods 20, 20.
... and the ring 21 support the workpiece holder 17 on the hand main body 3.

An air cylinder 22 for lifting and lowering the work holder having a vertical cylinder axis is attached to the periphery of the inner bottom surface of the upper part 4 of the hand body 3, and a piston rod 22a of this cylinder 22 extends upward, and its upper end is connected and fixed to the ring 21, and as the cylinder 22 expands and contracts, the workpiece holder 17 is moved up and down between the ascending end position and the descending end position.

Further, an annular suction passage 23 is formed at the upper end of the wall of the workpiece holder 17, and this suction passage 23 connects to the workpiece suction surface 18 at the lower end of the workpiece holder 17 through communication passages 23a, 23a,
It communicates through...

A suction pipe 24 communicating with the suction passage 23 is screwed into the upper end of the workpiece holder 17 in an airtight manner.
is connected to an air suction source (not shown) such as a vacuum pump, and when the workpiece suction surface 18 of the workpiece holder 17 is brought into contact with the spacer W on the workpiece mounting platform while the air suction source is activated. , the spacer W is attracted and held by the attraction surface 18.

Further, on the outer peripheral surface of the cylindrical portion 4a of the hand main body 3, three hanging rods 25 are provided at three equal positions in the circumferential direction.・
...is suspended and supported. The lower part of the capacity lowering rod 25 extends to the outer peripheral side of the work holder 17, and a work supporting device 26 consisting of a small air cylinder is attached to the lower end thereof.

That is, each work supporting device 26 is connected to the hanging rod 25.
The main body 2 of the device as a cylinder body is inserted and supported at the lower end of the centering tool 12 so as to be directed downward toward the center of the centering tool 12.
6a, and a support claw 26b serving as a piston rod that is retractably supported by the device main body 26a.
The support claws 26b move forward and backward relative to the lower position of the spacer W held by the workpiece holder 17 when the support claws 26b are moved out and out of the workpiece holder 6a.

Next, the operation of the above embodiment will be explained.

When the hand device A starts operating, a constant extension pressure is applied to the cylinder 6, as shown in FIG. 1, and this extension pressure applies a downward biasing force to the centering tool 12. Further, the cylinder 22 is in a contracted state, the workpiece holder 17 is at the lower end position, and the lower end workpiece suction surface 18 is positioned at a lower position than each workpiece support device 26 (the lowest end position of the hand device A). ing. moreover,
The work supporting device 26. 26. Each of the supporting claws 26b is recessed into the device main body 26a.

From the above state, first, the controlled body 1 moves downward above the workpiece mounting platform, and the entire hand body 3 descends, and as shown by the imaginary line in FIG. When the spacer W (workpiece) on the workpiece mounting table comes into contact with the spacer W (workpiece), the spacer W is suctioned and held by the workpiece suction surface 18 by the air suction source. At this time, since the cylinder 22 is in a contracted state, the excess pressing force of the spacer W is absorbed by the air compressibility of the cylinder 22 in the extending direction.

Thereafter, the cylinder 22 extends and the work holder 17 rises to the rising end position, and in this state, the controlled body 1 is moved to the shaft B.
move upwards. Next, the workpiece support device 26. 26
．． After each of the support claws 26b protrudes and their tips move forward below the spacer W at the rising end position, the suction of the spacer W by the air suction source is released, as shown in FIG. Accordingly, the spacer W is placed and supported on each of the support claws 26b of the workpiece support devices 26, 26, .

After that, the controlled object 1 moves downward. As shown in FIG. 3, the lower step 13 of the recess 13 of the centering tool 12
When the bearing C of the shaft B is completely fitted into the shaft B and a predetermined signal is output from the hide sensor 15, centering is completed. Thereafter, the controlled body 1 further moves downward, and the spacer W is fitted around the spacer insertion portion 81 of the shaft B, and each workpiece support device 26 is placed in the way of the shaft B, as shown by the imaginary line in FIG. When the height reaches a height below , the downward movement of the controlled object 1 stops.

At this time, since the spacer W is inserted into the shaft B while being placed and supported by the support claw 26b of the workpiece support device 26, the load applied to the spacer W is only its own weight, and the spacer W and the shaft B are The frictional resistance that acts between the two is reduced, so there is no generation of abrasion powder.

Further, since a constant extension pressure is applied to the cylinder 6, the force with which the centering tool 12 presses the bearing C of the shaft B is constant, and the shaft B can be held stably.

Finally, the support claws 26b of each workpiece support device 26 are recessed into the device main body 26a, and the spacer W falls onto the stepped portion of the shirt (B), thus completing the insertion process of one spacer W. Thereafter, the same operation as above is repeated for each spacer W.

Therefore, in this embodiment, as described above, the spacer W
When inserted into the shaft B, the spacer W descends only by its own weight and is inserted around the shaft 8, so the spacer W is inserted into the shaft B without strong contact, reducing the generation of dust and the like. The λ-nd device A can be used in a clean room or the like.

In the above embodiment, a workpiece support device having a direct-acting support claw 26b that retracts from the device body 26a is used, but the support claw can be rotated between the spacer lower position and the retracted position. It is also possible to have a structure in which

It goes without saying that the present invention can also be applied to the case where a workpiece other than the spacer W as in the above embodiment is inserted into the shaft B.

(Effects of the Invention) As explained above, according to the invention according to claim (1), when a workpiece having a center hole is centered by a hand device and automatically inserted into a shaft, the workpiece held in the workpiece holder is By first transferring the workpiece onto the support claw of the workpiece support device and inserting it into the shaft in that state, the workpiece can be lowered around the shaft using only its own weight, reducing friction with the shaft. The hand device can be inserted without making strong contact with the hand device to eliminate the generation of dust, and therefore the hand device can be used without any trouble even in clean rooms where cleanliness is required.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a cross-sectional view of the workpiece before being sucked and held. FIG. 2 is a view equivalent to FIG. 1 showing the workpiece being held. FIG. 3 is a view corresponding to FIG. 1 showing a state in which the workpiece is inserted. A... Hand device 1... Controlled object 2... Floating mechanism 3... Hand body 6... Centering tool biasing cylinder 12... Centering tool 17... Work holder 18... Work suction surface 22... Work holder lifting sill 26... Work support device 26b... Support claw B... Shaft C... Bearing W... Spacer (work) Wl.・Center hole 2nd

Claims (1)

[Claims] (1) A hand device that holds a workpiece having a center hole and inserts it around a shaft, which includes a controlled body movable in at least two-dimensional directions including up and down, and a floating mechanism that connects the controlled body horizontally. A hand body supported so as to be freely movable in a direction, a centering tool for a pair of shafts supported by the hand main body so as to be movable up and down and biased to protrude downward, and a centering tool arranged concentrically around the centering tool. a work holder which is provided and is movably supported by the hand main body and holds a work; and a work holder on the outer circumferential side of the work holder, arranged at equal angular intervals concentrically with the centering tool. at least three workpiece support devices installed with openings, each of the workpiece support devices being able to move forward and backward with respect to the lower position of the workpiece held by the workpiece holder when the workpiece holder is at the rising end position. 1. A hand device characterized by having a supporting claw that supports the hand.