JP2008272867A - Parallel hands with lock mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide compact fluid pressure parallel hands with lock mechanism having structure for gripping a plurality of workpieces having different clamp diameters and preventing the workpiece from dropping down even in a condition having no fluid pressure any more. <P>SOLUTION: The fluid pressure parallel hands for converting the vertical movement of a piston of a fluid pressure cylinder into the movement into the right and left directions of a master jaw are provided with a rock cylinder for fixing a lock pin to a link and moving a cam vertically, a guide part for guiding the vertical movement of the cam slidably, and the cam moving vertically while the lock pin slides in a wedge part of the cam. A contact point of the lock pin and a guide is abutted on the cam by thrust of the rock cylinder, the cam is tilted, and the link is locked to prevent the workpiece from dropping down. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a parallel open / close fluid pressure hand that clamps a workpiece by opening and closing a claw with a fluid pressure cylinder.

A transfer hand using a fluid pressure cylinder is widely known, and is attached to the tip of a robot to clamp a workpiece and used for transfer and assembly.

There are many types of hands, which can be broadly divided into fulcrum hands in which the claws that clamp the workpiece pivot around the fulcrum and parallel hands that move in a straight line in the direction in which the claws approach and move away from each other.

The fluid pressure hand clamps and transports the workpiece, but if the supply of fluid pressure stops due to an unexpected situation such as a power failure or compressor failure, the workpiece cannot continue to be gripped and dropped. There are things that will let you. In that case, the workpiece may fall and hit a machine or a person, which is very dangerous.

As a fall prevention method, a method of generating a gripping force even when air is cut off by inserting a spring into the piston, a structure of a toggle type swing chuck as disclosed in Japanese Utility Model Publication No. 4-106190, As disclosed in Japanese Patent Laid-Open No. 4-2585, a structure has been proposed in which an auxiliary cylinder provided with a wedge perpendicular to the wedge of the piston is incorporated and locked by contacting the wedge.

However, the method of inserting the spring into the piston requires that the spring be contracted with air, so that it is possible to generate a gripping force that is smaller than the gripping force of the fluid pressure cylinder. There are things that will let you.

In addition, the method of making a toggle-type swing chuck structure is that if there is a variation in the workpiece dimensions, it will be clamped before going to the dead point, and in that case it is not configured to prevent the workpiece from falling, Not only is there a danger of dropping the workpiece, but since it is a fulcrum hand, only one specific workpiece diameter can be configured to prevent dropping.

In addition, a method of locking an auxiliary cylinder with a wedge that is orthogonal to the wedge of the piston and bringing the wedge into contact with each other is effective when the piston thrust is applied to the wedge when the claw is opened and closed by switching the fluid pressure. As the cylinder becomes larger, the auxiliary cylinder may not be released normally, and the piston is loaded directly, so fluid pressure leaks due to piston deformation and wear, and the overall length becomes longer. There's a problem.
Japanese Utility Model Publication No. 4-106190 Japanese Utility Model Publication No.4-2585

  An object of the present invention is to provide a compact fluid pressure parallel hand that can grip a plurality of workpieces having different clamp diameters and does not drop the workpiece even when the fluid pressure is cut off.

  As means for solving the above-mentioned problems, an operating shaft provided at the piston tip of the fluid pressure cylinder, a link rotatably connected to the body around the fulcrum shaft, a master jaw slidably held by a guide, and a master In a fluid pressure parallel hand in which an operation shaft provided on the jaw converts the vertical movement of the piston to the left and right movement of the master jaw via the link, the lock pin is fixed to the link, and the lock cylinder moves the cam up and down, A guide part that slidably guides the vertical movement of the cam and a cam that moves up and down while the lock pin slides in the wedge part of the cam are provided in the fluid pressure parallel hand. The cam tilts when it comes into contact with the cam and locks the link to prevent falling.

By attaching the lock mechanism to the fluid pressure parallel hand using the link, the cam tilts with the thrust of the lock cylinder around the lock pin provided on the link, regardless of the size of the workpiece clamped. Since the contact point between the cam and the guide portion locks the cam, the force to open the master jaw is locked by the locked cam and the lock pin, and the master jaw cannot be opened.

The present invention also relates to a parallel open / close hand. When clamping a workpiece having a different size, it is possible to lock at any position, so that a setup change such as changing a claw is not necessary.

Further, unlike a conventional hand having a spring in a piston, it is not gripped by the elastic force of the spring, so that even if a load is applied, the master jaw does not open.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the parallel hand portion of the parallel hand with a lock mechanism of this embodiment is connected to the fluid pressure cylinder for the hand composed of the cylinder 1 and the piston 2 and the piston 2 to link A4 and link B5. The inserted operation shaft B10, the master jaw 6 configured to be slidable by the guide A7 fixed to the body 3, the operation shaft A9 fixed to the master jaw 9, and the fulcrum shaft 8 fixed to the body 3 It comprises a link A4 that pivots about the center and an operating shaft A9 that is inserted into the link B5.

The lock mechanism is configured to be slidable up and down by being connected by a working cylinder C16 by a lock cylinder comprising a cylinder B11, a piston B12 and a spring 19 provided beside the cylinder 1 and a guide B15 provided beside the link. The cam 13 is configured.

The cam 13 is connected to the piston B12 with a slight clearance and moves up and down in conjunction with the up and down movement of the piston B12.

In this case, the cylinder A1 and the cylinder b11 and the guide A7 and the guide B15 may be configured integrally or separately.

Next, the operation will be described. FIG. 1 shows a state in which the parallel hand is opened.

Explaining the operation of closing the parallel hand and clamping the workpiece, the piston A2 flows in from the lower port by switching the fluid pressure, and lifts the piston A2 and rotates the links A4 and B5 connected by the operating shaft B10. Then, the master jaws 6 connected by the operation shaft A9 are started in a direction to approach each other, and the claw (not shown) fixed to the master jaw 6 moves until the workpiece is clamped.

At this time, the lock cylinder is lowered by the piston B12 being pushed by the spring 19 and lowered until the wedge portion of the cam 13 hits the lock pin 14.

The cam 13 is guided by a guide B15 so as to be slidable up and down. However, the cam 13 rotates around the lock pin 14 due to the contact between the cam 13 and the lock pin 14, and as shown by the wavy line in FIG. The operation shaft C16 and the contact point 18 are tilted and locked until the contact point 18 contacts the guide B15.

In this case, even if the fluid pressure is cut off due to an unexpected situation such as a power failure, the force to open the master jaw 6 tries to push up the cam 13 by pushing the operating shaft C16 fixed to the link B5. Since the operating shaft C16 and the contact point 18 are tilted and locked until they contact the guide B15, they cannot be pushed up.

Next, the operation in the opening direction will be described.

The piston A2 switches the fluid pressure to flow the fluid pressure from the upper port, lowers the piston A2, rotates the link A4 and the link B5 connected by the operating shaft B10, and moves the master jaw 6 connected by the operating shaft A9. Start in directions away from each other.

In the lock cylinder, the piston B12 is raised by injecting fluid pressure to the lower side of the piston B12. At this time, the cam 13 is tilted and the force locked in the direction of correcting the tilt is lifted. Since it works, it is possible to release the lock.

In this embodiment, the upper port of the cylinder A1 and the lower port of the cylinder B are communicated and the opening / closing control is performed using a common switching valve. However, the fluid pressure of each cylinder is switched separately using the switching valve. Also good.

The above configuration relates to a parallel hand with a lock mechanism that clamps the workpiece by opening and closing the claw with a fluid pressure cylinder, but not limited to the hand, to those using a link rotation mechanism such as a clamp jig Can also be deployed.

Configuration diagram of the open state of this embodiment Configuration diagram of the embodiment in the closed state Explanatory drawing showing cam tilt Part drawing showing link shape

Explanation of symbols

1 Cylinder A
2 Piston A
3 Body 4 Link A
5 Link B
6 Master Job 7 Guide A
8 fulcrum shaft 9 working shaft A
10 Actuation axis B
11 Cylinder B
12 Piston B
13 Cam 14 Lock pin
15 Guide B
16 Actuation axis C
17 Connecting part 18 Contact point 19 Spring

Claims (1)

  An operating shaft provided at the piston tip of the fluid pressure cylinder, a link rotatably connected to the body around the fulcrum shaft, a master jaw slidably held by a guide, and an operating shaft provided in the master jaw In the fluid pressure parallel hand that converts the vertical movement of the piston to the left and right movement of the master jaw through the link, the lock pin is fixed to the link and the cam moves up and down, and the vertical movement of the cam is slidably guided And a cam that moves up and down while the lock pin slides at the wedge portion of the cam is provided in the fluid pressure parallel hand, the contact point of the lock pin and guide abuts the cam with the thrust of the lock cylinder, and the cam tilts. A parallel hand with a lock mechanism, which features a fall prevention by locking the link.