JPH0226586Y2 - - Google Patents

Description

[Detailed description of the invention] <<Industrial application>> This invention raises the workpiece on the workpiece pedestal by swinging the action point of the clamp arm placed above the clamp body downward using a hydraulic cylinder. Regarding the type of hydraulic clamp that presses and fixes from
This technology allows for a wide range of changes in clamp height.

<<Prior Art>> This type of balance type hydraulic clamp has the following basic structure.

For example, as shown in FIG. 1 or FIG. 5, a swing support 4 and a hydraulic cylinder 5 are installed vertically in parallel on a clamp body 3, and the fulcrum of a scale-shaped clamp arm 6 is placed on the clamp body 3. By swingably supporting the portion 6a with the swing support 4 and driving the force point portion 6b with the hydraulic cylinder 5, the application point portion 6 is
c is configured to be clamped downward.

In this prerequisite structure, conventionally a fifth structure is used to pivot and swing the clamp arm 6.
As shown in the figure, the swing support 4 is attached to the clamp body 3.
Hydraulic cylinder 5
The clamp arm 6 is attached to the upper end surface of the piston rod 25a.
The force point portion 6b of the two was brought into contact. Note that the swing support 4 is secured to the clamp body 3 by tightly fitting its leg shaft portion 4a into the screw hole 1a of the workpiece pedestal 1.
fixed at a constant height.

<<Problems to be solved by the invention>> In the above conventional example, the change width h ₁ of the clamp height is
Since the swing dimension of the point of action portion 6c corresponding to the lift of the point of force portion 6b of the clamp arm 6 is limited, the range of change is small.

Moreover, when clamping in the upper or lower region of the clamp height change width h ₁ , as the clamp arm 6 tilts up and down from the horizontal position, the transmission loss due to lateral pressure between the moving abutting parts increases. ,
The clamping force gradually decreases.

The object of the present invention is to enable a wide range of change in clamp height, and also to enable strong clamping even in the upper or lower range of the range of change in clamp height.

<<Means for Solving the Problems>> In the above-mentioned premise structure, the present invention provides a structure for pivotally supporting and swinging the clamp arm 6 as shown in FIGS. 1, 2, or 3, for example. It is characterized by being configured as follows.

That is, the leg shaft portion 4a of the swing support 4 is fitted into the height adjustment fixing hole 14 within the clamp body 3 so that the height can be adjusted, and the upper piston rod 31 is moved upward from the upper end surface of the piston 25 of the hydraulic cylinder 5. At the same time, the lower piston rod 32 is made to protrude downward from the lower end surface thereof, and a height adjustment hole 37 is formed from the upper end surface of the upper piston rod 31 to at least the middle part of the lower piston rod 32, thereby adjusting the height. The output rod 38 is fitted into the hole 37 so that its height can be adjusted, and the output portion 38a at the upper end of the output rod 38 is connected to the force point portion 6b of the clamp arm 6.

<<Operation>> According to the present invention, the clamp arm 6 and the output rod 38
is the vertical dimension from the low position A shown in the solid line in Figure 1 to the high position B shown in the chain double-dashed line.
h ₂ , the clamp height can be adjusted significantly in accordance with the height of the workpiece W while keeping the clamp arm 6 in a substantially horizontal standard position.

To switch from the low position state A to the high position state B, after adjusting the swing support 4 higher than the height adjustment fixing hole 14, move the output rod 38 through the height adjustment hole 37.
You can adjust it higher than that. On the other hand, switching from the high position state B to the low position state A is performed by an operation opposite to that described above.

In the above case, the width of change in the clamp height is the vertical dimension h ₂ shown in Figure 1 plus the swing dimension h ₁ shown in Figure 5, and this vertical dimension h ₂ is equal to the swing dimension h ₁ . Since the clamp height can be set much larger than before, the clamp height can be changed much more widely than before.

Furthermore, within the adjustment range of the lifting dimension _h2 , the workpiece W can be clamped with the clamp arm 6 in a horizontal position, and within this range, no transmission loss due to side pressure occurs, so a large clamping force can be obtained. As a result, in view of the entire clamp height change width, strong clamping can be performed even in the upper or lower region.

"Example" Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show one embodiment of the present invention, with FIG. 1 being a longitudinal sectional side view and FIG. 2 being a plan view.

In the figure, reference numeral 1 is a workpiece pedestal made up of a machining center table, a workpiece pallet, etc., and a workpiece W is placed on this workpiece pedestal 1 with a balance type hydraulic clamp 2.
It is fixed by pressing. The hydraulic clamp 2 has a clamp body 3 that is placed on a workpiece pedestal 1, and a swing support 4 is vertically provided in the front part of the clamp body 3 (on the left side in the figure). A hydraulic cylinder 5 is provided vertically at the rear of the main body 3 (on the right side as above). Reference numeral 6 denotes a balance-shaped clamp arm, and a fulcrum portion 6a formed at the middle portion of the clamp arm 6 in the front-rear direction is swingably supported on the upper part of the swing support 4. By swinging the force point part 6b formed at the rear part of the clamp arm 6 upward by the hydraulic cylinder 5, the force point part 6c formed at the front part of the clamp arm 6 moves around the fulcrum part 6a. It is swung downward toward W. This causes the clamp arm 6 to perform a clamping operation.

In the hydraulic clamp 2 described above, the swing support 4 and the hydraulic cylinder 5 are configured so that the height of the clamp arm 6 can be adjusted in accordance with the height of the workpiece W.

First, the swing support 4 will be explained. This swing support 4 is supported by a vertical threaded cylinder 11 provided across the workpiece pedestal 1 and the clamp body 3. The T leg 9 of the vertical threaded cylinder 11 is fitted into the T groove 12 of the work holder 1, and the vertical threaded cylinder 11 is fitted into the vertical through hole 13 in the clamp body 3. A height adjustment fixing hole 14 is formed in the inner peripheral surface of the vertically threaded cylinder 11. The swing support 4 is inserted from above into the loose fitting hole 16 vertically extending through the intermediate portion of the clamp arm 6 in the longitudinal direction, and the leg shaft portion 4a is inserted into the height adjustment fixing hole 14. Height-adjustable screw fit.

A clamp arm 6 is supported on the upper part of the swing support 4 via a spherical joint 18 so as to be swingable in the front-rear direction and pivotable in the horizontal direction. That is, the above-mentioned spherical joint 18 is attached to a concave spherical seat 18a formed at a mid-height position of the loose fitting hole 16, and between this concave spherical seat 18a and the head 4b of the swing support 4. It consists of a convex spherical catch 18b. Further, between the spring bearing nut 19 screwed onto the upper end of the leg shaft portion 4a of the swing support 4 and the lower surface side of the clamp arm 6, the clamp arm 6 is biased toward the head 4b of the swing support 4. A conical compression coil spring 20 is attached.

Next, the aforementioned hydraulic cylinder 5 will be explained. This hydraulic cylinder 5 has a cylinder chamber 23 whose axis is vertically oriented, and is configured as a single acting spring return type.

That is, a piston 25 is slidably inserted into the cylinder chamber 23 in an oil-tight manner, a drive chamber 26 is formed below the piston 25, and a spring chamber 27 is formed above the piston 25. 24 is a head cover whose four corners are screwed to the clamp body 3. An oil supply/drainage port 28 is opened in the drive chamber 26, and a head cover 2 is opened in the spring chamber 27.
A return spring 29 is installed between the piston 4 and the upper surface of the piston 25.

An upper piston rod 31 protrudes upward from the upper end surface of the piston 25 to cover the head cover 24.
A lower piston rod 32 protrudes downward from the lower end surface of the piston 25.
The axial center of the upper piston rod 31 is offset from the axial center of the piston 25, so that even if a rotational force is applied to the piston 25 around the axial center, the upper part of the upper piston rod 31 is prevented from rotating by the head cover 24. The rotation of the piston 25 is restrained. On the other hand, the lower piston rod 32 is located coaxially with the piston 25, and the guide hole 34
It is held in the clamp body 3 in a non-rotating manner by a linear guide 33 consisting of a non-rotating pin 35 and a non-rotating pin 35.

A height adjustment hole 37 is formed approximately coaxially with the axis of the piston 25 from the upper end surface of the upper piston rod 31 to at least a midway portion of the lower piston rod 32. A bolt-shaped output rod 38 is screwed into the height adjustment hole 37 so that the height can be adjusted, and an output portion 38 formed at the upper end of the output rod 38
a is connected to the force point portion 6b of the clamp arm 6. A stopper member 39 is fitted to the lower end of the output rod 38, and this restricts the output rod 38 from reaching a predetermined height or higher.

FIG. 3 shows another embodiment, and a different configuration from the above embodiment will be explained. In this embodiment, a fixing hole 14 for adjusting the height of the swing support 4 is formed in the clamp body 3, and the leg shaft portion 4a of the swing support 4 is fitted into the clamp body 3 so that the height can be adjusted. Ru.

FIG. 4 shows yet another embodiment. In this embodiment, the output rod 3 is attached to the force point 6b of the clamp arm 6.
A steady rest groove 41 that engages the output portion 38a of No. 8 is formed. This prevents the clamp arm 6 from pivoting in the horizontal direction during clamp operation. Note that in order to retract the clamp arm 6 from the workpiece W during unclamping, the swing support 4 is first advanced upward to lift the clamp arm 6, and then the steady rest groove 41 and the output portion 38a of the output rod 38 are connected to each other. , and then the clamp arm 6 may be pivoted in the horizontal direction.

In each of the above embodiments, the fulcrum part 6a is formed at the middle part of the clamp arm 6 in the longitudinal direction, and the force point part 6b is formed at the rear part of the clamp arm 6. A fulcrum part 6a is formed at the fulcrum part 6a, and this fulcrum part 6a is swingably supported by the swinging support 4. A force point part 6b is formed at the intermediate part in the front and back direction of the clamp arm 6, and an output rod is attached to this force point part 6b. Thirty-eight output portions 38a may be connected. In this case, by swinging the force point 6b of the clamp arm 6 downward with the hydraulic cylinder 5,
The action point portion 6c is clamped downward.

<<Effects of the invention>> Since the present invention is constructed and operates as described above, it has the following effects.

The range of change in clamp height is the vertical dimension _{h2 shown} in Figure 1 plus the swing dimension h1 shown in Figure 5, and this vertical dimension _h2 is significantly larger than the swing dimension _h1 . Since the clamp height can be set larger, the range of change in clamp height is much larger than in the past.

Moreover, in the adjustment range of the above-mentioned lifting and lowering dimensions,
The workpiece can be clamped with the clamp arm in a horizontal position, and within this range there is no transmission loss due to side pressure, so a large clamping force can be obtained. As a result, in view of the entire clamp height change width, strong clamping can be performed even in the upper or lower region.

[Brief explanation of the drawing]

Figures 1 to 4 show an embodiment of the present invention, and Figures 1 and 2 are one embodiment, where Figure 1 is a longitudinal sectional side view, Figure 2 is a plan view, and Figure 3 is another example. FIG. 4 is a partial view showing still another embodiment, and FIG. 5 is a longitudinal side view showing a conventional example. 1...Work pedestal, 2...Hydraulic clamp, 3...
... Clamp body, 4 ... Swing support, 4a ... Leg shaft section, 5 ... Hydraulic cylinder, 6 ... Clamp arm,
6a...Fully point part, 6b...Point of force part, 6c...Point of action part, 9...T leg, 11...Vertical screw cylinder, 13...
Vertical through hole, 14...Fixing hole for height adjustment, 25...
Piston, 31... Upper piston rod, 32...
...Lower piston rod, 37...Height adjustment hole, 3
8... Output rod, 38a... Output section.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A swing support 4 and a hydraulic cylinder 5 are installed vertically in parallel on the clamp body 3, and the fulcrum part 6 of the scale-shaped clamp arm 6 is mounted on the clamp body 3.
A balance-type hydraulic clamp configured to swingably support a with a swing support 4 and drive its force point 6b with a hydraulic cylinder 5 to clamp its action point 6c downward. The leg shaft portion 4a of the swing support 4 is fit into the height adjustment fixing hole 14 within the clamp body 3 so that the height can be adjusted, and the upper piston rod 31 is projected upward from the upper end surface of the piston 25 of the hydraulic cylinder 5. At the same time, the lower piston rod 32 is made to protrude downward from the lower end surface thereof, and a height adjustment hole 37 is formed from the upper end surface of the upper piston rod 31 to at least the middle part of the lower piston rod 32. output rod 38
The output rod 3 is fitted in a height-adjustable manner.
A balance type hydraulic clamp characterized in that an output part 38a at the upper end of the clamp arm 6 is connected to a force point part 6b of the clamp arm 6. (2) The height adjustment fixing hole 14 is formed by a cylindrical hole of the vertical threaded cylinder 11, the T leg 9 is fixedly installed at the lower part of the vertical threaded cylinder 11, and the vertical threaded cylinder 11 is formed by a vertical through hole of the clamp body 3. 13. The balance-type hydraulic clamp according to claim 1 of the utility model registration claim, which is slidably inserted into the clamp. (3) Connect the height adjustment fixing hole 14 to the clamp body 3.
A balance-type hydraulic clamp according to claim 1 of the utility model registration claim, which is formed as follows. (4) A fulcrum part 6a is provided at the middle part of the clamp arm 6 in the front and back direction.
The balance-type hydraulic clamp according to claim 1 or 2, which has a force point portion 6b formed at the rear thereof.