JPH01228746A - Work holding device - Google Patents

Abstract

PURPOSE:To facilitate selection and changeover of a reference sheet and a natural patch to be used to make maintenance such as chip ejection, etc. easier by attaching the reference sheet and the natural patch to a single lift rod in a work holding device for a machine tool. CONSTITUTION:A first body part 3, a second body part 4, and an intermediate cavity part 5 are formed in a work holding bed 1, a work supporting part 2 is provided in each body part 3, 4 and a clamper device 6 is provided in the body part on the opposite side of the supporting part. A lift rod 9 is fitted into a sleeve 8 of the body part 3, and a natural patch 10 and a reference sheet 11 are attached to a stepped supporting member 12 on the top end of the lift rod. A fluid pressure cylinder 14 is provided in the lower end part of the lift rod 9. And further, a stopper 22 is projected by the operation of a fluid pressure cylinder 20, the wedge 23 is also projected by spring force of a compression spring 24, and they are engaged with a long hole 25 and a wedge hole 26 respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a workpiece holding device used in a machine tool.

[Conventional technology]

Generally, when processing a workpiece, when it is necessary to hold the workpiece without distortion and maintain sufficient holding force against the cutting force during processing, the plunger is elastically attached to the workpiece through a wedge. A natural clamper is used to hold the workpiece by pressing on it.

Therefore, in a conventional workpiece holding device, a plurality of pairs of a reference sheet and a natural sheet are provided on a workpiece support stand, and both can be driven to vertically displace them independently.
Depending on the shape of the workpiece, one of the pairs may be selectively used.

[Problem to be solved by the invention]

In conventional workpiece holding devices, the reference sheet and the natural abutment are located close to each other and are capable of being driven independently up and down, resulting in a narrow gap between the two, which poses an obstacle to the discharge of cutting waste. , the structure is also complicated.

[Means to solve the problem]

The workpiece holding device of the present invention is a lifting support that is provided on a workpiece support stand at an appropriate location according to the shape of the workpiece so as to be able to rise and fall freely, and in which a reference sheet and a natural stop are formed in steps at the upper end. A load is applied to the body, a lifting drive device for the lifting support, and a spring force is applied to the lifting support via a wedge to cause an upward displacement, and a spring force load is applied to the lifting support.
A lifting support pressing device that can be switched with no load, a lifting displacement restraining device that can be freely engaged and disengaged from the lifting support so as to suppress the upward displacement caused by the lifting support pressing device in a fixed position, and a lifting support pressing device that can be freely switched. It consists of a workpiece pressing device that can press and release objects.

[For production]

Some of the lifting supports provided at a plurality of locations are used in a standard sheet usage mode and others are used in a natural dowel usage format.

First, before the workpiece is carried in and held, the upward displacement restraining device is in a position separated from the lifting support to allow upward displacement.

The lifting support pressing device is in a state where no spring force is applied to the lifting support, and the lifting support is in a lowered position by the lifting drive device. The workpiece pressing device is in a release position in which it does not press the workpiece against the lifting support.

In the above state, the workpiece is carried onto the workpiece support table while being supported by a transfer bar or the like located at the conveyance height.

Therefore, the lifting support is raised by the lifting drive device 6. In the workpiece support using the reference sheet, the lifting restraint device is activated to prevent the lifting support from rising above a predetermined height as the lifting support is raised. Move to a position where it engages your body. As a result, the elevating support body engages with the upward displacement restraining device and is displaced upwardly until the upward displacement is inhibited at a predetermined position. At this time, the elevating support pressing device engages with the elevating support via a wedge due to the spring force, thereby suppressing the lowering of the elevating support. As a result, the elevating support body is fixed at that position, and as it rises, the workpiece is lifted up to a predetermined position from above the transfer bar with the reference sheet, and is supported at a predetermined position in the vertical direction.

The workpiece pressing device then presses the workpiece against the lifting support.

On the other hand, in a lifting support using a natural stop, the natural stop comes into contact with the surface of the contacting portion of the workpiece as the lifting support is raised by the lifting drive. Therefore, a load is applied by the lifting support pressing device.

The lifting support and the wedge of the lifting support pressing device are engaged with each other by the pressing force of the spring force, and the lowering of the lifting support is inhibited, and a natural clamp is performed on the previous abutting portion.

In this way, the workpiece is fixedly held at the station by the workpiece holding device, predetermined machining is performed, and after machining, the workpiece W is released from the workpiece holding device.

To do this, the workpiece pressing device is first placed in the release position and moved away from the workpiece. Therefore, in the lifting support using a standard sheet and the lifting support using a natural dowel, the lowering restraint state by the lifting support pressing device is released, and the lifting support using a standard sheet is released from the upward displacement restraining device. ,
The lifting support is lowered to the lowered position I by the lifting drive.

By this lowering, the workpiece is transferred from the reference sheet and the natural dowel onto a transfer bar or the like at the conveyance height, and then supported by the transfer bar or the like and conveyed to the next station.

Depending on the shape of the workpiece, the use of a standard sheet or the use of a natural tool can be selected by switching between spring force loading and unloading of the lifting support pressing device on the lifting support and the operation sequence of the lifting support and lifting support pressing device. All you have to do is switch.

[Example] An example of the present invention will be described with reference to the drawings.

The workpiece holding device in the embodiment of this invention is as follows.

It has a structure as shown in FIGS. 1, 2, and 3, and is provided at each processing station of a machine tool 1, for example, a transfer machine.

The workpiece W conveyed to the workpiece support stand 1 of the processing station is firmly held by a workpiece holding device and processed.

Workpiece support portions 2 are formed on the workpiece support table 1 at appropriate locations depending on the shape of the workpiece W. In the illustrated example, they are arranged in two rows at three locations in the transport direction.

The workpiece support table 1 is formed with a first main body part 3, a second main body part 4, and an intermediate recessed part 5 that extend parallel to the conveying direction, and each main body part 3, 4 has a standard sheet natural meeting device for three pieces. A workpiece support 2 is provided, and one workpiece support 2 is provided.
On the other hand, a clamper device 6 is provided in each of the main body portions on the opposite side. In the illustrated example, the clamping device 6 corresponding to the intermediate workpiece support 2 is omitted.

As an example of a device for conveying a workpiece, the intermediate concave portion 5 includes:
A transfer bar T is provided, and a workpiece pressing rod B of a workpiece pressing device itA for pressing a workpiece W onto each workpiece support portion 2 is provided above the workpiece support stand 1.

A workpiece holding device will be described with reference to FIG. 1, representing a set of workpiece support portion 2 and clamper device 6.6 A hollow hole 7 is bored in the vertical direction in the first main body portion 3, and a hollow hole 7 is formed in the first body portion 3 in the upright direction. A sleeve 8 is fitted and fixed, and an elevating rod (elevating support) 9 is slidably fitted to the sleeve 8, and at its upper end, a natural dowel IO and a reference sheet U are arranged in a stepped manner ( The upper end becomes the natural abutment lO, and the stepped part becomes the reference sheet 11). The supporting member 1 is formed.
2 is installed.

An actuating plate 13 is horizontally fixed to the lower end of the elevating rod 9, and a hydraulic cylinder (elevating drive device) 14 for elevating is provided below the actuating plate 13 in the first main body 3.

The piston rod I5 of the fluid pressure cylinder 14 is formed in a stepped manner, and the upper small diameter portion 16 extends through the actuation [13].
A flange portion 17 is formed at the upper end, and a compression spring 19 is fitted between the step portion 18 and the lower surface of the actuating plate 13.

Then, the first main body portion 3 is provided with a stopper device (an upward displacement restraining bag!!) and a wedge device (an upward/downward support pressing device) in a vertical direction toward the upward/downward lever 9 in parallel above and below. Both of them are fluid pressure cylinders 20, 21,
The piston rod of the fluid pressure cylinder 2o has a stopper 22 at its tip, and the piston rod of the fluid pressure cylinder 21 has a wedge 23 at its tip.
In this case, the wedge 23 is urged to protrude forward by a compression spring 24 fitted within the cylinder when the hydraulic cylinder is inactive.

When the lifting rod 9 is in the raised position, the stopper 22 is
Projected by forward movement of the fluid pressure cylinder 20.

When the wedge 23 is protruded by the spring force of the compression spring 24, it can penetrate the sleeve 8 and engage with a long hole 25 and a wedge hole 26, which are diametrically bored in the lifting rod 9. There is.

A bell crank-shaped clamper member 27 whose one end is a contact part and the other end is an operating part is pivotally attached to the upper part of the second main body part 4 so as to be rotatable around a horizontal axis.
7, the second main body part 4 is provided with a hydraulic cylinder 28 for a clamper in an upright direction, and the piston rod extending upward serves as a clamper operating shaft 29 to operate the second main body part 4.
The actuating portion of the clamper member 27 is engaged with the circumferential groove at the upper end thereof.

Each fluid pressure cylinder is operated under sequence control by a hydraulic circuit (not shown).

The operation of the workpiece holding device described above will be described.

Some of the workpiece support parts 2 provided at a plurality of locations are used in a standard sheet usage mode, and others are used in a natural regular usage format. In the illustrated example, three workpiece supports are used at alternate locations.

First, the stopper 22 is in the retracted position due to the operation of the fluid pressure cylinder 20, and is pulled out from the elongated hole 25 of the lifting rod 9. The wedge 23 is in the retracted position against the spring force of the compression spring 24 due to the operation of the hydraulic cylinder 21, and a clearance is maintained between the wedge 23 and the wedge hole 26.

Further, due to the operation of the fluid pressure cylinder 14, the elevating rod 9 is also in the lowered position via the elevating plate 13 and the flange portion 17.

Also in the clamper device 6, the operating shaft 29 is in the lowered position due to the operation of the fluid pressure cylinder 28, and the clamper member 2
7 is in the released position rotated clockwise in FIG.

In the above state, the workpiece W is carried onto the workpiece support table 1 while being supported by the transbar T at the transport height. Therefore, by the operation of the fluid pressure cylinder 14, the piston support 15,
The lifting rod 9 is raised via the step portion 18, the compression spring 19, and the lifting plate 13.

At the same time, in the workpiece support section 2 using the reference sheet, the stopper 22 is moved by the operation of the fluid pressure cylinder 20.
It moves to the forward position and protrudes into the elongated hole 25. Then, the elevating rod 9 rises until the lower end surface of the elongated hole 25 abuts against the stopper 22 and is fixed at that position. As a result of this lifting, the workpiece W is lifted up from above the transfer bar T using the reference sheet 12 and supported in a fixed position in the vertical direction. At this time, the hydraulic cylinder 21 is deactivated, and the wedge 23 is advanced as far as possible into the wedge hole 26 by the spring force of the compression spring 24, so that the lifting rod 9 has a wedge effect between the wedge 23 and the wedge hole 26. This prevents the vehicle from descending.

On the other hand, in the clamper device 6 corresponding to the workpiece support 2 using the reference sheet, the operating shaft 29 is raised by the operation of the fluid pressure cylinder 28, and the clamper member 27 is rotated counterclockwise in FIG. , the workpiece W is a natural deposit of 10
Press it against the side of the

Then, the workpiece W is pressed and fixed onto the reference sheet 11 from above by the workpiece pressing rod B (as shown in FIG. 1).

At the same time, in the workpiece support section 2 using a natural dot, the natural dot 10 is interposed between the operating plate 13 and the stepped portion 18 due to the lifting of the lifting rod 9 by the operation of the fluid pressure cylinder 14 mentioned above. It is supported only by a compression spring 19, and is brought into contact with the surface of the contact portion of the workpiece W with its spring force. Therefore, the fluid pressure cylinder 2
1 is deactivated, the wedge 23 advances as far as possible into the wedge hole 26 due to the spring force of the compression spring 24, engages with the wedge hole 26 with a pressing force of the wedge 23 based on the spring force, and moves up and down. The lowering of the rod 9 is inhibited, and natural clamping is performed on the previous contact portion.

The transfer bar T has an intermediate concave portion 5 in preparation for the next conveyance.
(solid line in Figure 1).

Thus, the workpiece W is fixedly held at the station by the workpiece holding device, predetermined machining is performed, and after the machining, the workpiece W is released from the workpiece holding device.

To do this, first raise the workpiece pressing rod B to the release position,
Move it away from the workpiece W. At the same time, in the clamper device 6 corresponding to the workpiece support 2 using the reference sheet, the operating shaft 29 is lowered to the lowered position by the operation of the fluid pressure cylinder 28, and the clamper member 27 is rotated clockwise in FIG. to release the pressure on the side surface of the natural stopper 10 of the workpiece W. Then, the transfer bar T also rises to the conveying height.

Therefore, the fluid pressure cylinder 21 is activated in the workpiece support section 2 using the reference sheet and the workpiece support section 2 using the natural dowel, and the wedge 23 is moved back to the retreat position against the spring force of the compression spring 24. However, a play gap is generated between the wedge hole 26 and the wedge hole 26. Then, the stopper 22 is moved back to the retreat end by the operation of the cylinder 20, and after the lifting rod 9 is released,
Due to the operation of the fluid pressure cylinder 14, the elevating rod 9 is moved to the elevating plate 1.
3 and the flange portion 17 to the lowered position.

By this lowering, the workpiece W is transferred from the reference sheet 12 and the natural dowel lO onto the transfer bar T, and is supported by the transfer bar T and transported to the next station.

Depending on the shape of the workpiece W, etc., the use of the reference sheet or the natural alignment can be selected by switching the stopper 22 between the forward position and the backward position and switching the operating sequence of the lifting rod 9 and the wedge 23.

〔Effect of the invention〕

In the workpiece holding device according to the present invention, the reference sheet and the natural stop are attached to a single lifting rod,
Moreover, it is easy to selectively switch between using the standard sheet and using the natural winnings.

Therefore, the structure is simple, maintenance such as removal of cutting waste is easy, and the cost is low.

[Brief Description of the Drawings] Fig. 1 is a partially sectional front view of a workpiece holding device in an embodiment of the present invention, Fig. 2 is a front view of a workpiece holding device in an embodiment of the present invention, and Fig. 3 is the same side view. ■ = Workpiece support 2: Workpiece support 3: First main body 4: Second main body 5: Intermediate recess 6: Clamper device 7: Hollow hole
8; Sleeve 9: Lifting rod lO: Standard seat on natural support 1 12: Supporting member 13: Operating plate 14.20, 21.28: Fluid pressure cylinder 15: Piston support 16; Small diameter section 17: Flange section 18 Two stages Part 1.9, 24: Compression spring 22: Stopper 23: <
Rust 25: Long hole 26: Rust hole 27: Clamper member 29: Clamper operating shaft A: Workpiece pressing device B: Workpiece pressing shaft
Tnidor transfer bar W: Workpiece

Claims (1)

[Claims] An elevating support is provided on the workpiece support table at an appropriate location according to the shape of the workpiece so that it can be raised and lowered, and a reference sheet and a natural stop are formed in a stepped manner at the upper end, and an elevating support for the elevating support is provided. device, a lifting support pressing device that applies a load with a spring force via a wedge to the lifting support so as to cause an upward displacement, and that can freely switch between spring force loading and no load on the lifting support; and a lifting support pressing device. The workpiece is composed of an upward displacement restraining device that can be freely engaged and disengaged from the lifting support so as to suppress the upward displacement caused by the lifting support at a fixed position, and a workpiece pressing device that can freely press and release the workpiece against the lifting support. object holding device