JPH0985665A - Hand for minute part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To certainly grasp a workpiece and to surely separate the workpiece from grasping tool by providing an elevating pin arranged so as to come into pushed contact with the upper face of a part to be grasped with claws, and a stopper set so that its lower face may be below the lower face of the claw. SOLUTION: The driving device 7 of a pusher 3 is actuated to move a movable body 3d downwards for pushing the tip face 3e of a pin 3a against a work 10. In this case, the work 10 placed on a seat 20 is corrected to be horizontal, even if the tip part 4a of a stopper 4 pressedly pushes the seat 20 to produce hollow in the seat 20 for making the work to incline. Next, claws 2a, 2b are moved to grasp the work 10. In this case, since the tip parts of the claws 2a, 2b are slightly upper than the lower face of the tip part 4a of the stopper 4, the claws move smoothly without coming into contact with the seat 20. After that, the pin 3a is risen to complete grasping action.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hand for microparts, which is an end effector of a robot or the like for transferring and assembling microparts of small or thin parts.

[0002]

2. Description of the Related Art In handling a minute component (hereinafter also referred to as a work), suction or gripping is generally used. For example, as shown in FIG. A gap adjusting portion 32 having a flat surface 36 having an ejection hole 34 for ejecting a plurality of air is provided in the frame 30 having the claws 31a and 31b, and the upper surface of the table 50 and the claws are ejected by the air ejected from the ejection hole 34. There is a hand that adjusts the gap G at the tips of 31a and 31b and holds a work without bringing the claws into contact with the table (Japanese Patent Laid-Open No. 57-61489). The operation is as follows.

To the work 40 placed on the table 50,
The frame 30 is lowered, and the claws 31a, 3 are attached to the table 50.
Move 1b closer. At this time, since the set optimum air is ejected toward the upper surface of the table 50 from the air ejection holes 34 provided in the flat surface 36 of the gap adjusting section 32,
The frame 30 is floated by the air pressure ejected, the table 50 and the claws 31a and 31b are not in contact with each other, and the descent of the frame 30 is stopped while maintaining a predetermined gap G. Even if the frame 30 descends right and left when the frame is tilted to the left and right, the gap adjusting portions 32 are provided on the left and right, so that the levitation force on the side that comes closer to the upper surface of the table 50 first becomes large. The frame 30 rotates left and right around the center of the table 50, and the claws 31a, 31
b is horizontal.

[0004]

The conventional hand is set on an adhesive tape or the like because the work is simply splashed by the air flow when the work is simply placed on the table. Only applicable in the case. But,
There is no problem with a thin tape, but when it is placed on a thick tape or an elastic body such as a sponge-like sheet,
Due to the air pressure ejected from the air ejection holes of the gap adjusting section, the upper surface of the elastic body is deformed into a concave shape, and the work is inclined unless the work is set in the center of the left and right gap adjusting sections. In such a state, when the claw is moved to perform the gripping operation of the work, the work is tilted with respect to the claw, and therefore a gripping error is often caused especially for a thin article. In addition, since the small work piece is extremely light,
The influence of gravity on the fall of the work when the work is gripped and released is relatively small, but rather is greatly affected by static electricity or dirt, and it may not be possible to separate the work from the nail by simply opening the nail. An object of the present invention is to provide a hand for minute parts which can be surely gripped by a nail and cut at the same time even if a work is set on a thick elastic body whose thickness accuracy is not so good.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a pair of openable and closable pawls, an ascending / descending pin arranged to press the upper surface of a component held by the pawl, and a lower surface of the pawl below the lower surface of the pawl. It is characterized by comprising a stopper set to and a moving table on which these are placed.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail with reference to FIGS. FIG. 1 is a front view of the hand of this embodiment, and FIG. 2 is a side view thereof. The work 10 is a rectangular magnetic head having dimensions of about 2 mm × 1 mm × 0.5 mm, and is set on a sheet 20 having a thickness of several mm, which is made of foam resin and has an adhesive layer on the upper surface. The sheet 20 is cut out from a large sheet and attached to the table base, and the height position of the sheet 20 after attachment varies due to manufacturing errors of the sheet and attachment errors.

A vertical movement mechanism is attached to a hand base 5 attached to a wrist of a robot or the like (not shown), and a block 1 and a stopper 4 are fixed to a movement table 6 of the movement mechanism. The block 1 is provided with a chuck 2 for holding a work and a pusher 3 for pressing the work. The pusher 3 includes a moving body 3d that moves vertically and is connected to a driving device 7 such as an air-cylinder, a connecting portion 3c attached to the moving body 3d, and a cushion 3b made of, for example, a spring or rubber, on the connecting portion 3c. Has a pin 3a attached thereto. The tip surface 3e of the pin 3a is formed so as to come into surface contact with the upper surface of the work 10. The connecting portion 3c has a structure in which the pin 3a can be replaced according to the target work. The chuck 2 has a pair of claws 2a and 2b, and is synchronously moved to the left and right by a driving unit (not shown). Nail 2
The a and 2b are set so as to have a substantially equal distance in the left-right direction about the pin 3a, and the width in the front-rear direction is set so that the pin 3a is substantially in the center.

The stopper 4 is provided with a sheet 2 at its tip 4a.
The surface facing 0 is substantially U-shaped. The claws 2a and 2b are arranged in the substantially U-shaped space so that they are substantially at the center. The lower surface of the tip portion 4a is formed to be smooth, and the nail 2
It is arranged to be 0.05 mm to 0.2 mm below the tips of a and 2b. Note that this value may be appropriately determined according to the work thickness. In this embodiment, the moving table 6
There is no drive attached to the, and it usually hangs by its own weight. Therefore, when the robot descends and the tip 4a of the stopper 4 hits the sheet 20, for example, the moving table 6
While lifting his / her own weight on the seat 20, he / she will be lifted up in the movement range. At this time, if the mating surface of the sheet or the like is flat, the claw will not hit the mating surface.
Even if a drive device is attached to the moving table 6 and movement control is performed separately, it is easy to perform the same operations as described below.

Next, the operation will be described. FIG. 3 is a diagram showing an operation of gripping the work 10. The robot 10 is moved, and the hand is placed on the upper surface of the sheet 20.
After moving it to just above, it is lowered (FIG. 3 (a)).
At this time, the height of the upper surface of the seat 20 varies,
By appropriately determining the descending amount of the robot, the tip portion 4a of the stopper 4 can be always brought into contact with the sheet 20 with a constant force. That is, the robot descends largely, and the excess descending portion is allowed to escape on the moving table 6.

Next, the driving device 7 of the pusher 3 is activated,
The movable body 3d is moved downward to press the tip surface 3e of the pin 3a against the work 10. At this time, in the work 10 placed on the sheet 20, the tip 4a of the stopper 4 is placed on the sheet 2
Even if the sheet is dented by pressing 0 and thus tilted, it will be corrected horizontally (Fig. 3).
(B)). Since the pin 3a is connected to the connecting portion 3c via the cushion 3b, the work 10 is not damaged because an excessive pressing force is not applied.

With the work 10 corrected horizontally, the claws 2a and 2b are moved to grip the work 10 (FIG. 3).
(C)). At this time, the tip portions of the claws 2a and 2b are slightly above the lower surface of the tip portion of the stopper 4 as described above, so that the claws 2a and 2b can move smoothly without contacting the sheet 20. After that, the pin 3a is raised to complete the gripping operation (FIG. 3 (d)). By this series of operations, the work 10 is reliably gripped, and after the gripping operation is completed, the robot moves to convey the work 10 to a predetermined position.

Next, the separating operation of the work 10 after conveyance will be described with reference to FIG. After transporting the work 10 to a predetermined position (FIG. 4A), the hand is lowered. At this time, similarly to the gripping operation, first, the front end portion 4a of the stopper 4 first hits the transfer surface of the work, and the work 10 does not drop anywhere because it does not interfere with anything. After that, the pawls 2a and 2b are moved to open the work 10, and the pusher 3 is activated to lower the pin 3a. By lowering the pin 3a, the work 10 can be reliably separated from the claws 2a and 2b (FIG. 4 (b)).

[0013]

According to the present invention, since it is constructed as described above, the work can be reliably carried out even if the work placement height position accuracy is poor or the work is placed on the elastic body. The grip can be gripped, and it can be reliably separated from the gripper, enabling extremely reliable handling.

[Brief description of drawings]

FIG. 1 is a front view of a hand according to an embodiment.

FIG. 2 is a side view of the hand of the embodiment.

[Fig. 3] Work gripping operation

[Figure 4] Workpiece separation operation

FIG. 5 is a front view of a conventional hand.

[Explanation of symbols]

 2 Chuck 3 Pusher 4 Stopper 6 Moving table 10 Work piece 20 Sheet

Claims (1)

[Claims] 1. A pair of opening and closing claws, an ascending and descending pin arranged so that the upper surface of a component gripped by the claw can be pressed against, a stopper set such that its lower surface is below the lower surface of the claw, and these. A hand for minute parts, which is composed of a moving table placed on it.