JPH0636795U - Work gripping device with rollers on the gripping arm - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a work holding device for a robot hand that can always supply a work to a machine tool or the like in a correct posture regardless of the shape and posture of the work. [Structure] The work gripping device 10 has a pair of gripping arms 14 and 16 attached to a hand portion 12. Gripping arm 1
Reference numerals 4 and 16 perform linear expansion and contraction movements in equal amounts with respect to the hand portion 12. At the facing parts of the gripping arms 14 and 16,
The V-shaped bases 22 and 24 are fixed. Laura 2
6, 28 are gripping arms 14, 1 at the tip of the base 22.
6 is pivotally attached so as to project in the direction of movement. Roller 30,
32 is pivotally attached to the tip of the base 24 so as to project in the movement direction of the gripping arms 14 and 16. Work W is roller 2
Rolls into contact with 6, 28, 30, 32 to correct the posture.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a work gripping device provided in a robot hand in a robot that supplies a work to a machine tool or the like.

[0002]

[Prior art]

 A robot may be used to supply a work conveyed to the vicinity of the machine tool to the machine tool. Most of such robots have a robot hand, and the robot hand has, for example, a work gripping device at its tip.

As shown in FIG. 3, the conventional work gripping device 50 has gripping arms 54 and 56 that can be expanded and contracted with respect to the hand portion 52. Claws 58 and 60 for gripping the work W are attached to the respective gripping arms 54 and 56.

[0004]

[Problems to be solved by the device]

 The conventional work gripping device 50 as described above has the following problems. (1) It is mainly designed to handle cylindrical and columnar workpieces, and when handling polygonal workpieces, it is necessary to prepare claws that match the contour of the workpiece. (2) When the shape of the work to be handled changes, the claws must be replaced each time, and the setup needs to be changed, which lowers the production efficiency. (3) In order to grip the work, the work must be aligned in the specified direction. Otherwise, the work gripping device cannot grip the work. Moreover, even if the work can be gripped, the work cannot be supplied to the machine tool when the work is in the wrong posture.

[0005]

[Means for Solving the Problems]

 The present invention provides the above-mentioned object by the work gripping device, which has a pair of gripping arms attached to the hand part of the robot and having a mutual interval expanding and contracting, and two pairs of rollers pivotally mounted so as to face the gripping arms. Solved.

[0006]

[Action]

 When the hand portion reaches the work placement position and the mutual distance between the gripping arms is reduced, the roller comes into contact with the work. A work piece in the correct posture is gripped between the opposing rollers. Since the work is gripped between two pairs of rollers, the shape of the work that can be handled is not limited. A workpiece that is not in the correct posture makes rolling contact with the rollers when the gripping arm contracts, and the posture is corrected correctly. Then, the work is sent to the next step.

[0007]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. The work gripping device 10 is used by a robot (not shown) that supplies a work placed on a pallet of a feeder to a machine tool. The work gripping device 10 is attached to a robot hand.

FIG. 2 is an enlarged view near the tip of the robot hand. The work gripping device 10 has a pair of gripping arms 14 and 16 attached to the hand unit 12. The holding arms 14 and 16 linearly move with respect to the hand unit 12. In the figure, the upper gripping arms 14 and 16 are shown in an open state, and the lower gripping arms 14 and 16 are shown in a closed state. The gripping arms 14 and 16 expand and contract in equal amounts with respect to the center line L1.

V-shaped bases 22 and 24 having recesses 18 and 20 are fixed to the gripping arms 14 and 16, respectively. The two pairs of rollers 26, 28, 30, 32 are pivotally mounted so as to be located in the same plane at the tips of the respective bases 22, 24 and project inside the gripping arms 14, 16. The rollers 26 and 28 are symmetrical with the rollers 30 and 32 with respect to the line L1.

As shown in the figure, when handling a hexagonal work W, the rollers 26, 28, 30, 32 come into contact with the surface of the work W. Since the rollers 26, 28, 30, 32 project from the bases 22, 24 and the recesses 18, 20 are formed in the bases 22, 24, the work interferes with the gripping arms 14, 16 and the bases 22, 24. It is possible to handle workpieces of various shapes without doing so.

In FIG. 2, the work W on the upper side is not in an original correct posture. In such a case, the rollers 26, 28, 30, and 32 make rolling contact with the surface of the work W during the contracting operation to correct the posture of the work W. This is because the two pairs of rollers 26, 28, 30, 32 are provided symmetrically.

As described above, the work gripping device 10 of the present invention can handle any shape of work and has an automatic centering function. Therefore, it is not necessary to perform troublesome setup change and work rearrangement, and the present invention greatly contributes to automation of the entire processing apparatus.

[0013]

[Effect of device]

 Since the present invention has the above-mentioned configuration, it has the following remarkable effects. (1) Since the two pairs of rollers pivotally attached to the gripping arm grip the work from the surroundings, the shape of the work that can be handled is not limited. It can handle both cylindrical and polygonal workpieces. (2) As in the conventional case, the work of replacing the claw is unnecessary, and the production efficiency is improved. (3) Since the roller pivotally attached to the gripping arm grips the work, the work is corrected to a correct posture during the gripping operation, and it is not necessary to align the work. Therefore, a device for aligning the work is not required, and the cost can be reduced. (4) Since the roller makes rolling contact with the work, the work surface is not scratched even if the work posture is corrected.

[Brief description of drawings]

FIG. 1 is a plan view of a work gripping device according to the present invention,
The operation when the work is in the correct posture is shown.

2 is a plan view of a work gripping device according to the present invention, FIG.
The operation is shown when the work is in an incorrect posture.

FIG. 3 is a plan view of a conventional work gripping device.

[Explanation of symbols]

 10 Work Grasping Device 12 Hand Part 14, 16 Grasping Arm 26, 28, 30, 32 Roller

Claims (1)

[Scope of utility model registration request] 1. A work gripping device comprising a pair of gripping arms attached to a hand part of a robot and having a mutual interval expanding and contracting, and two pairs of rollers pivotally mounted so as to face the gripping arms.