JPS627197A - Robot hand - 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] [Field of Application of the Invention] The present invention is applicable to the transfer of electronic parts and small parts, the insertion and assembly of electronic parts into printed circuit board assemblies, etc.

This invention relates to a robot hand used for moving or transferring workpieces, inserting and assembling workpieces, etc.

[Prior Art] Conventional robot hands for inserting and assembling electronic components into printed circuit board assemblies, for example, have a finger opening width that is opened in advance for chucking electronic components in a workpiece supply section, and a width of a finger opening that is opened in advance to chuck electronic components in a work supply section, and a robot hand for inserting and assembling electronic components into a printed circuit board assembly. The finger opening widths that open after insertion and assembly were formed to be the same.

If the positioning accuracy of the electronic components in the workpiece supply section is high, the opening width of the fingers may be narrow; on the other hand, if the positions of the electronic components in the workpiece supply section are uneven, the fingers may be opened wide before chucking. This made it possible to securely grasp the electronic components.

[Problems to be Solved by the Invention] However, when the positioning accuracy in the work supply section is high and chucking is performed with a narrow opening width, the opening width is narrow even when releasing the printed circuit board after inserting it, causing damage to adjacent components on the board. Although there is no risk of this happening, if the positioning accuracy in the workpiece supply section is rough and chucking is performed with a wide opening width, the opening width will become wide even when separating electronic components after inserting a printed circuit board, resulting in contact with adjacent parts, etc. could damage adjacent parts or fingers.

The present invention has been made in view of the above-mentioned drawbacks of the prior art.The accuracy of workpiece positioning in the workpiece supply section is rough, and even when chucking is performed with a wide opening width of the fingers, it is difficult to release the workpiece after inserting the workpiece. The purpose of the present invention is to provide a highly reliable robot hand in which the finger opening width can be narrowed and there is no risk of damaging the workpiece or the fingers.

[Structure of the Invention] The robot hand according to the present invention includes a pair of fingers each pivotally supported at one end and provided facing each other so as to be openable and closable, and a biasing means for biasing the fingers in a closing direction.
The inner plunger is inserted between the pair of fingers and has a large-diameter portion formed in the longitudinal direction, and an outer plunger is provided coaxially outside the inner plunger, and the large-diameter portion of the inner plunger and the outer plunger are provided coaxially on the outside of the inner plunger. By selectively inserting the plunger between the pair of fingers against the biasing force of the biasing means, the opening width of the fingers can be independently switched into two stages.

[Embodiments of the Invention] Next, embodiments of the present invention will be described based on FIGS. 1 to 5.

FIG. 1 is a sectional view showing a robot hand assembly according to the present invention. In FIG.
A hand assembly mounting flange 14 having a boat A communicating with an air passage 12 therein is fitted.

This hand assembly mounting flange 14 has screws 1
Inner cylinder 1 as the first cylinder inside by 5
6. An outer cylinder 18 as a second cylinder is coaxially attached to the outside so as to cover the inner cylinder 16 in a double structure.

The inner cylinder 16 and the outer cylinder 18 each have
It is equipped with an inner plunger 20 and an outer plunger 22 to be guided in the vertical direction. Of these, the outer plunger 22 has a piston portion 24 at its upper end, and this piston portion 24 is slidably guided between the inner cylinder 16 and the inner cylinder 16 inside the seventh outer cylinder 18 . A compression coil spring 26 is disposed below the piston portion 24, and constantly biases the piston portion 24 upward. On the other hand, a boat B is bored at the upper end of the outer cylinder 18, and compressed coil spring 2 is supplied with pressure air from this boat B.
By pressing the piston part 24 from above against the force 6 and moving it downward, and conversely removing the pressure air from the boat B, the piston part 24 can be returned upward by the pressing force of the compression coil spring 26.

Air in the outer cylinder 18 on the lower side of the piston portion 24 enters and exits through a boat D provided at the lower end of the outer cylinder 18.

The lower end side of the outer plunger 22
When 2 returns upward, it protrudes outward from the boat D by a predetermined length. The outer plunger 22 is formed hollow in the axial direction.

The inner plunger 20 has a piston portion 28 at its upper end, and the piston portion 28 is slidably guided between the hand assembly mounting flange 14 inside the inner cylinder 16. A compression coil spring 30 is disposed below the piston portion 28.
The piston portion 28 is always urged upward.

A detent shaft 32' is provided between the hand assembly mounting flange 14 and the lower end of the inner cylinder 16 at an eccentric position parallel to the inner plunger 20, and prevents the inner plunger 20 from rotating around its axis. There is.

By supplying pressurized air from boat A, the piston part 28 is pressed from above against the compression coil spring 30 and moved downward, and conversely, by removing air from boat A, the pressing force of the compression coil spring 30 is reduced. This allows the piston portion 28 to return upward.

The lower side of the inner plunger 20 is
When the plunger returns upward, it slidably passes through the center of the inner cylinder 16 and the outer plunger 22 provided on the same axis, and extends further downward to a predetermined position, and a work holder 34 is attached to the tip with a screw 36. It is fixed. Since the inner plunger 20 is restrained from rotating around the axis while the device is moving, the workpiece holder 34 can be designed to have an arbitrary shape depending on the shape of the workpiece 38, so that the workpiece 38 can be pressed easily and reliably. When changing the type of workpiece 38, the workpiece holder 34 can also be easily replaced.

The inner plunger 20 is provided with a port C through which air in the inner cylinder 16 on the lower side of the piston portion 28 is taken in and out to the outside. This bow) C is piston part 2
8 and at the side of the inner plunger 20 which is still exposed to the outside when the outer plunger 22 moves to the lowest position with the inner plunger 20 in its restored state.

Above the approximate center of the inner plunger 20 is a stepped portion 40 that has a smaller diameter below and a larger diameter above the lower end position of the outer plunger 22 when both the inner plunger 20 and the outer plunger 22 return upward. A rising end surface 42 of the zero stepped portion 40 (see FIG. 2) is an inclined surface that is connected to the tip surface 44 of the outer plunger 22 when the inner plunger 20 and the outer plunger 22 are in the returned state.

An inner plunger 20 is provided at the lower end of the outer cylinder 18.
A pair of left and right fingers 46 are provided with the tips of the fingers 46 sandwiching them in such a way that they can be freely opened and closed.

Of these, the finger 46 on the left side in FIG. 1 is provided with a finger holder 48 that sandwiches the left side of the lower end of the outer cylinder 18 from the front and back in a substantially U-shape and is pivotally supported by a pin 50. The lower end side of the inger holder 48 is rotatable in the left-right direction.

A bearing 52 as a roller is inserted into the finger holder 48 and pivotally supported by a pin 49 in the opening near the inner plunger 20 at the lower end of the finger holder 48, and a part of the bearing 52 is attached to the finger holder. 48 in the direction of the inner plunger 20.

This bearing 52 is in contact with the inner plunger 20 or the outer plunger 22 and performs a cam action between them to open and close the fingers 46 from side to side.

The bearing 52 is provided at a position where it contacts the inner plunger 20 at a predetermined distance below the rising end surface 42 of the lower end of the stepped portion 40 when the inner plunger 20 is returned upward.

A claw 54 extending downward along the inner plunger 20 is attached to a screw 56 at the lower end flange portion of the finger holder 48.
is fixed. The lower end of this pawl 54 extends downward from the lower end of the workpiece holder 34 when the inner plunger 20 is returned upward, and the end portion is bent inward into an L-shape.

The finger 46 provided on the right side of the lower end of the outer cylinder 18 is also formed completely symmetrically with the left side. A tension coil spring 58 is provided between the left and right finger holders 48.
is stretched, and the finger 46 is connected to the inner plunger 2.
The force is applied toward the center of zero. left and right claws 5
4 can be replaced with a claw 54 of a different size by removing the screw 56.

The distance between the claws 54 during chucking can be changed depending on the dimension between the leads of the workpiece 38 and the like. The movement positions of the inner plunger 20 and outer plunger 22 are as follows:
It can be controlled by the injection time of pressurized air from ports A and B, pressure setting, position detection using a sensor, etc.

Note that, of course, the cylinder is not limited to a cylindrical shape.

[Effect] Next, the operation of the above embodiment will be explained.

In advance, when the inner plunger 20 and the outer plunger 22 return upward and the bearing 52 of the finger 46 comes into contact with the small diameter part of the inner plunger 20 by the tension coil spring 58, the opening width Ll at the tip of the claw 54 is the workpiece. 3
It is assumed that the lead-to-lead pitch is set to be slightly narrower than the lead-to-lead pitch of 8 (here, an IC is taken as an example).

In addition, the workpiece 38 in the workpiece supply section 60 (see FIG. 3)
The lateral positioning accuracy is rough and the workpiece 38 is reliable.
The claw 54 before chucking for chucking
It is assumed that it is necessary to have a large opening width.

First, after the entire robot hand is moved to a predetermined position above the workpiece 38 of the workpiece supply section 60, pressurized air is injected from bows A and B. By injecting this pressurized air, the inner plunger 20.7 and the outer plunger 22 descend against the compression coil springs 30 and 26.

During this descent, the rising edge 42. The inclined surface of the tip surface 44 hits the bearing 52 and pushes the left and right bearings 52 in the left and right outward directions, so that the finger 46 rotates in the left and right outward direction about the pin 50 against the tension coil spring 58.

When the inner plunger 20 and the outer plunger 22 descend further and the bearing 52 comes into contact with the side surface of the outer plunger 22, the bearing 52 opens by W2 in FIG. 2 on one side, and the tip of the claw 54 opens by a large opening width L2 It will be fully opened.

The outer plunger 22 is lowered until the piston portion 24 comes into contact with the lower end of the inner diameter □ of the outer cylinder 18, at which point the injection of pressurized air is stopped. On the other hand, inner plunger 2
0, the injection of pressurized air is stopped at a position where the work holder 34 is a predetermined distance above the lower end when the claw 54 is closed by a predetermined distance determined in advance according to the type of the work 38.

In this state, the entire robot hand descends, and when the work holder 34 comes adjacent to the work 38, the robot hand stops descending (see Fig. 3).When the work holder 34 comes into contact with the work 38, the work supply section 60 Variations in the accuracy of positioning the workpiece 38 in the height direction on the workpiece support table 62 are corrected.

Then, when the air is released from A and B, it is biased by the compression coil spring 30 and the compression coil spring 26, and the inner plunger 20. The outer plunger 22 rises, and the left and right fingers 46. Between the tension coil springs 5
Since the bearing 52 is biased by 8, the bearing 52 is energized by 7.
2 and comes into contact with the small diameter portion of the inner plunger 20.

At this time, the gap between the claws 54 is closed, the opening width is narrowed to Ll, and a predetermined central portion of the lead 64 of the workpiece 38 is gripped, and the lead 64 also protrudes by a predetermined length below the claws 54 ( (See Figure 4).

Next, while holding the workpiece 38, the entire hand is raised and moved above the insertion point of the printed circuit board 66. and,
The whole hand is lowered and the tip of the lead 64 of the workpiece 38 is inserted into several holes drilled in the printed circuit board 66 (
The lowering of the hand is stopped at the point where the lower end of the claw 54 contacts the printed circuit board 66.

Subsequently, pressurized air is supplied from port A to lower the inner plunger 20. A bearing 52 comes into contact with the side surface of the stepped portion 40 via the rising end surface 42 of the inner plunger 20, and this bearing 52 rotates outward from left to right around the bottle 50, opening by Wl on one side as shown in FIG. The space between the tips of the openings 54 is small and is half open by an opening width L2. As a result, the workpiece 38 is released from the grip of the claws 54. At this time, the opening width of the claw 54 is narrower than in the fully open state before chucking, and the claw 54 does not come into contact with adjacent components on the printed circuit board 66.

When the inner plunger 20 further descends, the workpiece holder 34 provided at the tip comes into contact with the workpiece 38 and presses it down.
Since the rotation of the inner plunger 20 is restrained by the rotation prevention shaft 32, the workpiece holder 34 formed to match the shape of the workpiece 38 reliably inserts the workpiece 38 into the printed circuit board 66 to bring it into an assembled state.

Then, with the piston part 28 in contact with the lower surface of the inner cylinder 16 by supplying pressurized air, the entire I\end is pulled up, the supply of pressure air is stopped at the upper position, and the workpiece is returned to its original position. The insertion/assembly process is completed.

Note that if the horizontal positioning accuracy of the workpiece in the workpiece supply section is high, the workpiece may be chucked by raising and lowering only the inner plunger, or if the distance between adjacent parts on the printed circuit board is large. In this case, the outer plunger may be lowered simultaneously with the lowering of the inner plunger to increase the opening width of the fingers when the workpiece is released.

[Effects of the Invention] As explained above, according to the present invention, the fingers are moved by the cam action performed by the step of the inner plunger and the finger, and the cam action performed by the step and the finger between the outer plunger and the inner plunger. The opening width when opened can be switched independently into two stages, so even if the workpiece positioning accuracy is rough and the finger opening width needs to be widened for chucking, the workpiece can be released after it is inserted. In some cases, the finger opening width can be narrowed to deal with restrictions such as date space on the insertion side, and this has the excellent effect of providing a highly reliable robot hand without the risk of damaging the workpiece or fingers.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the main parts of a robot hand according to an embodiment of the present invention, FIG. 2 is a schematic enlarged view showing part A in FIG. 1, and FIGS. 2 is an explanatory diagram of the operation of the robot hand shown in FIG. 1. FIG. 16... Inner cylinder, 18... Outer cylinder, 20... Inner plunger, 22... Outer plunger, 34... Work holder, 38... Fist work, 40-φ single step part, 46... ...Finger, 52...Bearing, 54...Claw, 58φ...Tension coil spring.

Claims (1)

[Claims] a pair of fingers that are each pivotally supported at one end and are provided facing each other so as to be openable and closable; a biasing means that biases the fingers in a closing direction; an inner plunger formed;
an outer plunger coaxially provided outside the inner plunger, and the large diameter portion of the inner plunger and the outer plunger are selectively inserted between the pair of fingers against the biasing force of the biasing means. By doing so,
A robot hand characterized in that the opening width of the finger can be independently switched between two stages.