JPH08300285A - Robot hand finger - Google Patents

Abstract

PURPOSE: To provide robot hand fingers capable of strong holding power in a simple structure. CONSTITUTION: A finger forming body 1 is formed with a tubular soft material, where a base end part is opened and the floating end is closed, and an intermediate peripheral part in the longitudinal direction of this finger forming body 1 is formed into a bellows form. An opening part 1a of this finger forming body 1 is interconnected to a fluid supplying part 3, and in a state that the base end of the finger forming body 1 is supported by a support member 2, a height size of each fold of bellows 18 is set, insomuch that it becomes the back side of the finger forming body 1 so as to get this finger forming body 1 bent to the web side by dint of pressure in a fluid out of the fluid supplying part 3 fed through the opening part 1a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention forms a finger forming body with a cylindrical soft material having a base end portion opened and a free end portion closed, and an opening portion of the finger formation body is connected to a fluid supply portion. In addition, the finger formation body is configured to bend toward the abdomen side by the pressure of the fluid from the fluid supply portion supplied through the opening while the base end portion of the finger formation body is supported by the support member. Regarding fingers for robot hands.

[0002]

2. Description of the Related Art Conventionally, as a finger for a robot hand described above, for example, as shown in JP-A-61-203287, one in which only the back side of a finger-formed body is formed in a bellows shape, As shown in Japanese Patent Publication No. 57-144687, the finger forming body is divided into two chambers, an abdominal side and a back side, and a plurality of grooved grooves are formed in the abdominal portion of the finger forming body and ridges are formed in the back portion along the width direction. Some were formed one by one.

[0003]

According to the above-mentioned conventional structure, in the former case, since the bellows portion is formed over the entire back portion and the area of the bellows portion is large, the finger forming body is increased when the fluid pressure becomes high. There is a risk of rupture, and only a low pressure fluid can be supplied, and the gripping force is weakened. Also in the latter case, since the finger formation body is divided into two chambers, the abdomen side and the back side, the structure is complicated, and the displacement of the finger formation body is small and the gripping force is weak.

An object of the present invention is to provide a finger for a robot hand which can obtain a strong gripping force with a simple structure.

[0005]

A feature of the present invention is that a finger-shaped body is formed of a cylindrical soft material having a base end portion opened and a free end portion closed, and a finger-shaped body is formed at an intermediate portion in the longitudinal direction of the finger-shaped body. The peripheral portion is formed in a bellows shape, the opening portion of the finger forming body is connected to the fluid supply portion in communication, and the base end portion of the finger forming body is supported by a supporting member and is supplied through the opening portion. The height of each fold of the bellows is set higher toward the back side of the finger formation so that the finger formation bends toward the abdomen side by the pressure of the fluid from the fluid supply section. Especially.

[0006]

According to the above construction, only the peripheral portion in the longitudinal direction of the finger forming body is formed into a bellows shape, and the height of each fold of the bellows is set higher toward the back side of the finger forming body. so,
Since the finger forming body is configured to be bent to the abdomen side, for example, compared to the case where the entire back portion is formed in a bellows shape,
It is possible to withstand a higher fluid pressure, and a simple structure can be obtained.

[0007]

Therefore, it is possible to provide a finger for a robot hand which can withstand a high fluid pressure and can obtain a strong gripping force while having a simple structure and reducing the manufacturing cost. did it.

[0008]

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a finger forming body 1 formed of an elongated tubular rubber material (an example of a soft material) having a base end portion opened and a free end portion closed, at a central protruding portion of a support member 2 corresponding to a palm. 2 supported and configured
A forefinger robot hand is shown. This robot hand is used to sort the cucumbers harvested in the harvest basket into different boxes according to grades such as size. The support arm that supports the support member 2 at the tip portion is a drive device (both together). By changing the position (not shown), the support member 2 is configured to be closely spaced to the harvest basket side.

Each finger body 1 has its end portion on the side of the opening 1a fitted onto the connecting end portion projecting from the support member 2 and fixed by a ring-shaped clip 5. Also, the support member 2
One connecting end of the connecting ends is divided from the main body of the support member 2 and bolted to the main body so that the direction and length of one finger forming body 1 can be changed to the other fingers. It is configured so that it can be changed and adjusted to match the direction and length of the forming body 1. The opening portion 1a of the finger forming body 1 is connected to an air flow passage R formed in the support member 2 so as to communicate with the air flow passage R, and the first pump is connected to the air supply / discharge port 10 on the tip side of the support member 2 in the air flow passage R. 3 (an example of a fluid supply unit) are connected to each other, and the longitudinal middle portion of the finger forming body 1 is formed into a bellows 18 in which the height dimension of each fold is higher toward the back side of the finger forming body 1 ( (See FIG. 4), first
The posture of each finger formation body 1 can be freely switched between a gripping posture in which each finger formation body 1 is bent to the abdominal side by the supply and discharge of pressurized air from the pump 3 and a grip release posture in which the finger formation body 1 is restored and extended to the back side. Configured.

The air flow passage R includes one main flow passage R1 extending from the front end side to the base end side of the support member 2 and a pair of sub-flow passages branching from the main flow passage R1 and respectively communicating with the opening 1a. And a flow passage R2. A hollow support shaft 6 is inserted from the tip end side of the support member 2 into the main flow passage R1 in a state where both longitudinal ends of the main flow passage R1 are shielded from the outside air, and cucumber is adsorbed on the tip of the support shaft 6 with cucumber. A bellows-shaped suction nozzle N that can act is connected, and this suction nozzle N is located outside the tip portion of both finger forming bodies 1 by a spring 14 provided between the suction nozzle N and the seal ring 7 on the tip side of the support member 2. It is urged to project to the side. The suction nozzle N has a support shaft 6
The air in the adsorption nozzle N from the hollow part of the second pump 2
It is configured such that it can be sucked at 0 and adsorbed on cucumber, and that the adsorbing action can be released by discharging air from an air supply / exhaust port (not shown) communicating with the hollow portion of the support shaft 6.

The main flow passage R1 is reduced in diameter in the vicinity of the center of the support member 2 so that the tip end side portion of the support member 2 is formed in the cylinder chamber 8 with respect to the reduced diameter portion, while the intermediate portion of the support shaft 6 is formed. Is formed on the piston 9 that reciprocally slides in the cylinder chamber 8.

The two auxiliary flow passages R2 are branched before the stroke end of the cylinder chamber 8, and as shown in FIG. 2, the pressurized air from the air supply / discharge port 10 causes the piston 9 to reach the stroke end. Then, the suction nozzle N lifts a certain amount of the cucumber, and then the two secondary flow passages R2 communicate with the air supply port 10, whereby the finger forming body 1 is bent to the abdominal side and grips the cucumber. It is configured as follows.

Further, the diameter-reduced portion is formed to have a larger diameter than the portion corresponding to the piston rod on the base end side of the support shaft 6, and a gap S is formed between the diameter-reduced portion and the support shaft 6 to support the support shaft 6. When the air discharge port 22 is formed on the side wall of the base end portion of the member 2, the pressurized air in the finger formation body 1 is first discharged a little from the air supply / discharge port 10 when the grip of the finger formation body 1 is released. After that, the air is discharged from the air discharge port 22. That is, when the pressurized air is discharged from the air supply / discharge port 10, the spring 14
When the support shaft 6 moves to the finger tip side by the urging force of, the piston 9 immediately shuts off the sub-flow passage R2 and the air supply / discharge port 10, and when the support shaft 6 further moves to the finger tip side, the auxiliary flow is generated. The path R2 communicates with the air outlet 22, and the pressurized air in the finger body 1 is discharged from the air outlet 22.

A pair of fins 4 extending outward in the width direction is formed at the fingertips of each finger forming body 1 (see FIG. 3) so that the cucumber can be reliably gripped with two fingers. As shown in FIGS. 1 and 4, the lead wire 15 is drawn from the support member 2 side into a groove formed in the abdomen along the longitudinal direction, and the first pressure-sensitive sensor 16 is provided on the distal end surface of the finger formation 1 and the abdomen. And a second pressure sensor 17 are provided separately (see FIG. 5). The second pressure-sensitive sensor 17 is an elastic pressure-sensitive sensor made of rubber, and the elastic pressure-sensitive sensor forms a grip surface.

The first and second pressure sensitive sensors 16 and 1 are also provided.
A control device 21 (an example of control means) capable of controlling the drive device, the first pump 3, and the second pump 20 based on the detection result of 7 is provided.

The robot hand having the above-mentioned structure is used in the control device 2
Execution of control No. 1 operates as follows. [1] The support member 2 approaches the harvest basket side. Suction nozzle N
When is adsorbed on the cucumber, the proximity drive of the support member 2 to the cucumber side is stopped (see FIG. 1. As a means for stopping the drive of the support member 2, for example, based on the contraction amount of the adsorption nozzle N, the control device 21 There is a means to stop the drive device. In this case, when the tip portion of the finger forming body 1 comes into contact with something other than cucumber, for example, and a pressing force of a certain amount or more is applied, the first pressure-sensitive sensor 16 detects that the pressing force is applied, Based on this detection information, the proximity drive of the support member 2 to the cucumber side is stopped, and the finger formation body 1 is prevented from being damaged.

[2] Pressurized air is supplied from the first pump 3 into the main flow passage R1, and the piston 9 is pushed against the urging force of the spring 14 to the side opposite to the fingertip side, and the support shaft 6 is moved. The cucumber is moved to the inner side of the support member 2 and a certain amount of cucumber is lifted.

[3] As shown in FIG. 2, the piston 9 reaches the stroke end, and the auxiliary flow passage R2 and the air supply / discharge port 10 are connected.
And the finger form 1 are bent to the abdomen side by the pressurized air and hold the cucumber. The second is that the gripping force has become constant.
When the pressure sensor 17 detects, the supply of the pressurized air is stopped, the air pressure in the finger forming body 1 becomes constant, and the bending operation is stopped. In this state, the support member 2 is separated from the harvest basket side by 1
Take out the cucumber from the book.

[4] The finger-formed body 1 is located above a predetermined position in a box to be newly accommodated, and pressurized air is discharged from the air supply / discharge port 10, so that the finger-formed body 1 releases its grip. start. As the pressurized air is discharged, the elastic restoring force of the spring 14 causes the support shaft 6 to move to the finger tip side, and the piston immediately shuts off the side flow passage R2 and the air supply / discharge port 10. When the support shaft 6 is further moved to the tip side of the finger, the auxiliary flow passage R2 communicates with the air discharge port 22, and the pressurized air in the finger forming body 1 is discharged through the gap S from the air discharge port 22, The forming body 1 returns to the grip release posture and extends. When this grip is released, the suction nozzle N projects toward the fingertip side and places the cucumber on the predetermined position in the box. The air in the suction nozzle N is discharged from the air discharge port communicating with the hollow portion of the support shaft 6 to release the suction of the cucumber.

[Other Embodiments] As shown in FIGS. 6 and 7A, a metal reinforcing plate 12 that bends via a hinge 11 may be built in the abdomen of the finger body 1. Further, the reinforcing plate 12 may be formed of a plastic material or another resin material. In that case, as shown in FIG. 7B, a bending groove 13 is formed along the width direction instead of the hinge. Form.

The finger forming body 1 may be formed of another soft material such as vinyl urethane instead of the rubber material.

The object to be grasped may be vegetables or fruits other than cucumber, or may be something other than food.

Three or more finger forming bodies 1 may be provided.

Instead of the pressurized air, the posture of the finger forming body 1 may be switched by a liquid such as pressurized hydraulic oil.

The bellows 18 may be provided at a plurality of positions in the longitudinal direction of the finger body 1 (see FIG. 6).

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a front view of a partially cutaway robot hand before gripping.

FIG. 2 is a partial cutaway front view of a robot hand showing a gripping operation.

FIG. 3 is a rear view of the tip portion of the finger forming body.

FIG. 4 is a cross-sectional view of a bellows portion of a finger body.

FIG. 5 is a cross-sectional view of a finger formation body.

FIG. 6 is a perspective view of another embodiment.

7A is a perspective view of another embodiment. FIG. 7B is a perspective view of another embodiment.

[Explanation of symbols]

 1 Finger Forming Body 1a Opening 2 Supporting Member 3 Fluid Supplying Section 18 Bellows

Claims (1)

[Claims] 1. A finger forming body (1) is formed from a cylindrical soft material having a base end portion opened and a free end portion closed, and the finger formation body (1) is formed.
Is formed into a bellows shape, the opening (1a) of the finger forming body (1) is communicatively connected to the fluid supply part (3), and the base of the finger forming body (1) is formed. With the end portion supported by the support member (2), the finger formation body (1) is folded to the abdomen side by the pressure of the fluid from the fluid supply portion (3) supplied through the opening portion (1a). Like to sing
A finger for a robot hand in which the height of each fold of the bellows (18) is set higher toward the back side of the finger forming body (1).