JPS63229235A - Workpiece holding device - Google Patents

Abstract

PURPOSE:To increase the margin of opening at the time of mounting and removal and increase durability while simplify structure by making a push pin slide along the inside of a grip body and projecting out and retracting contact members from said grip body to mount and remove a workpiece. CONSTITUTION:As a compressed air is fed into a space S via the flow passage 11a of a swinging arm 11 and the through hole 10f of a grip body 10, a push pin 13 is moved rightward against a spring 15, and, as a small diameter part 10a is fitted into a workpiece W, three steel balls 16 are brought into contact with the inner periphery of the workpiece W and retracted to install the workpiece W on the small diameter part 10a. Then, as the compressed air is stopped, the push pin 13 is advanced due to the spring 15 and the steel balls 16 are pushed out to hold the workpiece W on the grip body 10. When the compressed air is fed again, the push pin 13 is retracted failing to press the steel balls 16 outward, and a push out pin 22 is projected out to push out the workpiece W to be removed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a workpiece gripping device for gripping a workpiece in various conveyance devices such as robots and loaders.

[Conventional technology]

Conventionally, as shown in FIG. 4, in this type of workpiece gripping device, a rotation shaft 2 is mounted inside a support member 1, and a rotation shaft 2 is mounted inside a ring-shaped expander 3 fixed to the support member 1. , a movable member 4 is supported to be slidable up and down with the eccentric shaft portion 2a of the rotation shaft 2 fitted therein, and a suppressing member 6 is attached to the movable member 4 via a bolt 5, It is known that an annular collet 7 is attached to the outer peripheral inclined surface 3a of the expander 3, and a spring 8 is attached between the support member 1 and the collet 7 on the outside of the expander 3. ing.

When the workpiece W is to be gripped using this workpiece gripping device, the movable member is 4 is slid downward relative to the expander 3, the bolt 5 and the suppressing member 6 are lowered accordingly, and the pressing member 6 causes the collet 7 to be pushed along the outer peripheral inclined surface 3a of the expander 3 into a spring. Press downward against the spring force of 8. As a result, the collet 7 is elastically deformed and its diameter increases, so that the outer circumferential portion of the collet 7 comes into pressure contact with the inner circumferential surface of the workpiece W, thereby gripping and fixing the workpiece W.

[Problem that the invention seeks to solve]

However, the conventional workpiece gripping device using the collet 7 has the following problems.

That is, a) Since the workpiece W is fixed by the elastic deformation of the collet 7, it is not possible to provide a large opening margin when attaching and detaching the workpiece.

Mouth) Since the collet 7 repeatedly undergoes elastic deformation, there is a problem with durability.

c) Since the structure is complicated, it is difficult to manufacture, increases manufacturing cost, and cannot be processed if the inner diameter of the workpiece W is small.

The present invention has been made in view of the above circumstances, and its purpose is to provide a large opening margin when attaching and detaching a workpiece, to fix the workpiece and to hold it cheaply and reliably, and to have a structure that is F! An object of the present invention is to provide a workpiece gripping device that can be manufactured inexpensively and compactly using IIN and has excellent durability.

[Means for solving problems]

In order to achieve the above object, the present invention provides a grip body that loosely fits into the inner peripheral surface of a cylindrical workpiece, a push pin that is slidably provided inside the grip body and has an inclined surface, and a push pin that is slidably provided inside the grip body and has an inclined surface. a first urging means attached to the pin and urging the push pin in one direction, a second urging means attached to the push pin and urging the push pin in the other direction, and the grip an abutting member that is removably provided on the main body, and that contacts the inclined surface of the push pin as the push pin slides, protrudes outward from the grip main body, and contacts the inner circumferential surface of the workpiece; It is prepared.

[Effect]

In the work gripping device of the present invention, first. The push pin is slid along the inside of the grip body by the second biasing means, and the sliding of the push pin causes an abutting member that comes into contact with the inclined surface of the push pin to protrude outward from the grip body; Alternatively, it is retracted into the grip body, and the inner circumferential surface of the workpiece and the abutting member are brought into contact and separated from each other, thereby smoothly attaching and detaching the workpiece.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 3.

FIG. 1 is a cross-sectional view showing an example of a workpiece gripping device, FIG. 2 is a cross-sectional view taken along the line ■--■ in FIG. 1, and FIG. 3 is a cross-sectional view showing a state in which steel balls are supported. In these figures, reference numeral 10 indicates a hollow grip body, and this grip body 10
is a small-diameter tip portion 10a that loosely fits into the inner circumferential surface of the workpiece W;
Continuing with this tip small diameter portion 10a, and (for robots, etc.)
Intermediate portion 10 attached to the tip of fIIIial arm 11
b, and a large diameter portion 10 connected to the intermediate portion 10b and fixed to the swing arm 11 via a bolt 12.
It is composed of C. Then, the above-mentioned grip body 1
0 has a small hole 10d and a large hole 1 connected thereto.
0e is formed, and the push pin 13 has a new convex shape.
is slidably attached. Also, the gutter end side of the push pin 13 and the large hole 10e of the grip body 10 are connected to each other.
Between the fixing member 14 having a cross-section shape screwed into the
Push the push pin 13 in one direction (left side in Figure 1).
A spring (first biasing means) 15 is attached to press the spring. Furthermore, the bush bin 130 large diameter portion 13a
A stepped portion 13c is formed on the outer periphery of the tip end side (small hole portion 13d side), and an annular space S constituted by this stepped portion 13c and the inside of the grip body 10 is The inside of the swing arm 11 is communicated with a flow passage 11a for supplying compressed air via the through hole 10f. Furthermore, a steel ball (abutting member) 16 is loosely fitted into each of the three mounting holes 10a formed at equal intervals in the small diameter portion 10a of the tip of the grip body 10, and the steel ball 16 is The push pin 13 protrudes and retracts in a direction important to the axis of the grip body 10 while being regulated by the tapered part (slope part) 13d of the small diameter part 13b and the caulking part 17 provided at the outer exit of the mounting hole 10Q. It is set freely. Note that the symbols 18, 19, and 20 in Figure 1 are
Each is an O-ring, and these O-rings 18°19
．． The above-mentioned flow path iia, which is made airtight by 20,
By supplying compressed air to the ti through hole 10f and the space S, the bushing pin 13 is pressed against the spring 15.
A second biasing means 21 is configured to move the body in the other direction (to the right in FIG. 1). Further, reference numeral 22 denotes a push-out pin that is slidably attached to the grip body 10, and the push-out pin 22 allows the workpiece W to be released when gripping the workpiece.
is pushed out from the small-diameter tip portion 10a of the grip body 10.

When gripping and transporting a cylindrical workpiece W using a transporting device such as a robot or a loader incorporating a workpiece gripping device configured as described above, first, compressed air is supplied to the Road 11a.

It is supplied to the space S of the stepped portion 13C of the push pin 13 through the L1 through hole 10f of the grip body 10.

As a result, the push pin 13 moves inside the grip body 10 to the right in FIG. 1 against the spring force of the spring 15. In this state, when the small-diameter tip portion 10a of the grip body 10 is inserted into the workpiece W, the three steel balls 16 fitted into the mounting holes 1011) of the small-diameter tip portion 10a are attached to the inner peripheral surface of the workpiece W. Since the workpiece W is retracted into the mounting hole 10q upon contact, the workpiece W can be smoothly mounted on the small diameter portion 10a at the tip of the grip main body 10. At this time, the compressed air in the space S passes through the clearance between the small diameter part 13b of the push pin 13 and the small hole part 10d of the grip body 10, and is directed outward from the gap between the steel ball 16 and the Vt attachment hole 10g. Since the particles are ejected at the same time and in front of the push pin 13, dust, cutting powder, etc. adhering to the inner peripheral surface of the workpiece W can be blown away and removed.

Next, when the supply of the compressed air is stopped, the push pin 13 moves forward (moves to the left in FIG. 1) by the spring 15, and three pieces of steel are attached to the tapered part 13d at the tip of the push pin 13. By contacting the ball 16,
Each steel ball 16 is pushed outward and protrudes outward from the mounting hole 10Q.

As a result, the three steel balls 16 come into contact with the inner circumferential surface of the workpiece W, and the workpiece W is reliably held in the grip body 10. At this time, as mentioned above, since the dust and the like on the inner peripheral surface of the workpiece W have been removed, there is no dust and the like interposed between the steel ball 16 and the inner peripheral surface of the workpiece W, and the workpiece W is Grips with high precision.

In this way, after the workpiece W is transported while being reliably supported by the tip of the swing arm 11, when the gripping state of the workpiece W is released, compressed air is supplied into the space S again. As a result, the push pin 13 retreats (moves to the right in FIG. 1), the three steel balls 16 are no longer pressed outward by the tapered portion 13d of the push pin 13, and each steel ball 16 The workpiece W becomes retractable into the mounting hole 10Q, and the push-out pin 22 protrudes.
, the workpiece W can be easily removed from the small-diameter FIS 10a at the tip of the grip body 10.

In this embodiment, compressed air is used to move the push pin 13, but hydraulic pressure or electric power may also be used.

〔Effect of the invention〕

As explained above, the present invention provides a grip body that loosely fits into the inner peripheral surface of a cylindrical workpiece, a push pin that is slidably provided inside the grip body and has an inclined surface, and a push pin that is slidably provided inside the grip body and has an inclined surface. a first urging means attached to the push pin and urging the push pin in one direction; a second urging means attached to the push pin and urging the push pin in the other direction; , an abutment that is provided on the grip body so as to be freely retractable and that comes into contact with the inclined surface of the push pin as the push pin slides, protrudes outward from the grip body, and comes into contact with the inner circumferential surface of the workpiece. Since it is equipped with a member, the first. sliding the push pin along the inside of the grip body by the second biasing means;
As the push pin slides, the contact member that contacts the inclined surface of the push pin protrudes outward from the grip body or is retracted into the grip body, allowing the workpiece to be smoothly attached and detached, unlike the conventional method. Compared to the case where the workpiece is attached and detached using the elastic deformation of the collet, by adjusting the outward protrusion m of the grip body of the abutment member, the opening margin can be made larger, and the inner diameter of the workpiece can be increased. It is possible to flexibly respond to fluctuations in temperature, extremely easy to attach and detach a workpiece, and to improve durability.

In addition, since the structure is simple, it is easy to manufacture and has excellent effects such as being able to be manufactured inexpensively and compactly.

[Brief explanation of drawings]

1 to 3 show an embodiment of the present invention,
Figure 1 is a sectional view showing the overall configuration, Figure 2 is the ■-
FIG. 3 is a cross-sectional view illustrating the supporting state of a steel ball, and FIG. 4 is a cross-sectional view showing a conventional work gripping device. W...Work, 10...Grip body, 13...
Push pin, 15... spring (first biasing means)
, 16... Steel ball (contact member), 21... Second biasing means, 13d... Tapered part (slanted surface part).

Claims (1)

[Claims] A workpiece gripping device that grips a cylindrical workpiece by engaging with the inner peripheral surface of the workpiece includes a grip body that loosely fits inside the workpiece, and a sloped surface that is slidably provided inside the grip body. a push pin having a push pin, a first biasing means attached to the push pin and biasing the push pin in one direction, and a first biasing means attached to the push pin,
and a second biasing means for biasing the push pin in the other direction; and a second biasing means that is removably provided in the grip body and that comes into contact with the inclined surface of the push pin as the push pin slides. A workpiece gripping device comprising: a contact member that projects outwardly from the workpiece and contacts an inner circumferential surface of the workpiece.