JPH0243633Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a workpiece clamping device for fixing a workpiece during machining with a horizontal machine tool such as a horizontal machining center. This invention relates to a work clamping device in which a clamp block is made to protrude sideways from the side of a center block.

《Prior Art》 Conventionally, as a work clamp device used for a horizontal machine tool, a clamp block is placed on the side of a center block that is erected on a base so that it protrudes sideways, and a fluid pressure cylinder equipped on the clamp block is used. There are some that hold the workpiece in place by pressing it down from above.

The clamp block is assembled to the center block in such a way that its mounting height can be adjusted and changed, and in order to absorb the weight of the clamp block when adjusting the mounting height of the clamp block,
Balancer members such as constant force springs and gas springs are arranged.

[Problem to be solved] In a workpiece clamping device in which a hydraulic clamper is fixed to a center block so that it can be raised and lowered, the connection between the clamp block and the center block is not constant, so it is difficult to When supplying and discharging working fluid, it was necessary to connect the flow path switching valve fixed on the center block and the clamp cylinder with a wire braided hose, or to arrange the flow path switching valve directly on the cylinder block. .

However, when connecting the flow path switching valve placed on the center block and the clamp cylinder with a wire braided hose, the hose is arranged based on the maximum travel distance, so the hose becomes long, and this long hose gets in the way. The problem was that the work area became narrower and the hoses were damaged by the tools.

Furthermore, if a flow path switching valve is arranged for each clamp block, not only will the number of flow path switching valves increase, resulting in increased costs, but also the clamping operation will have to be performed individually, so the time required for clamping will increase. becomes longer and workability becomes worse. In addition, the piping up to the flow path switching valve becomes long, and the above-mentioned problem still remains.

<Means for Solving the Problems> The present invention solves the above-mentioned problems and provides a workpiece clamp that is easy to work with and does not expose the working fluid flow path to the clamp block in the working area. For this purpose, a clamp block, which is disposed in a movable manner relative to a center block, is supported by a counter member consisting of a hydraulic cylinder, and a piston rod of the hydraulic cylinder is connected to the clamp cylinder. Of the two working fluid chambers separated by the piston, the working fluid chamber in which the fluid supply/discharge port of the fluid pressure cylinder is open communicates with the working fluid flow path in the piston rod. At the same time, the two working fluid chambers were communicated, and one of the working fluid chamber and the working fluid flow path communicating with the working fluid flow path was connected to the working fluid supply path, and the other was connected to the single-acting cylinder for the clamp. It is characterized by this.

<<Operation>> In the present invention, the clamp block is supported by the center block via a counter member consisting of a fluid pressure cylinder, and a working fluid flow path to the clamp cylinder is formed in the piston rod of the fluid pressure cylinder, and is partitioned by the piston. The two working fluid chambers of the hydraulic cylinder in which the piston rod is located are communicated with each other, and the working fluid chamber in which the fluid supply/discharge port of the hydraulic cylinder is open is communicated with the working fluid passage formed in the piston rod. The working fluid to the cylinder will be supplied through the working fluid chamber of the counter cylinder and the passage in the piston rod.

Further, since the weight of the clamp block is received by the counter cylinder that communicates the working fluid chambers with each other, the clamp block is prevented from falling suddenly when adjusting the height of the clamp block.

Furthermore, since the working fluid chambers of the counter cylinders communicate with each other, when the clamp block is moved up and down, the working fluid moves between the working fluid chambers, allowing the clamp block to be quickly moved to the desired position. .

《Example》 Figure 1 is a central vertical cross-sectional view of the work clamp device.
FIG. 2 shows a perspective view thereof.

This work clamp device includes a base 1 fixed on the table of a horizontal machine tool, a prismatic center block 2 erected on the base 1, and a rising side wall 3 of the center block 2. It has a clamp block 4.

Inside the clamp block 4, a clamp cylinder 5 consisting of a spring double-return type single-acting hydraulic cylinder is arranged vertically.
A pressure oil passage 6 is formed horizontally. This pressure oil passage 6 opens to the mounting surface of the clamp block 4 to the center block 2.

Opposite rising side wall surface 3 of center block 2
has a cutout recess 8 for housing the counter cylinder 7.
is formed vertically, and this notch recess 8
Two T-shaped grooves 9 are vertically formed to guide the clamp block 4 up and down while holding the clamp block 4 between them. The clamp block 4 is guided by this T-shaped groove 9 and is fixed to the center block 2 in a state where the mounting height can be adjusted and changed.

As shown in FIG. 3, the counter cylinder 7 is constituted by a single-acting hydraulic cylinder, and its piston rod 10 is formed of a tubular body, with the inside of the piston rod 10 serving as a pressure oil communication passage 11.
A connecting block 13 having a pressure oil passage 12 formed therein is fixed to the protruding tip of the piston rod 10, and a clamp block 4 is fixed to this connecting block 13. Of the two hydraulic oil chambers 15 and 16 partitioned by the piston 14, a pressure oil supply/discharge port 17 opens in the hydraulic oil chamber 15 on the piston head side. The pressure oil supply/discharge port 17 is connected to a pressure oil supply path 18 formed within the center block 2. The piston head side hydraulic oil chamber 15 and the pressure oil communication passage 11 in the piston rod 10 are connected to the piston 10.
They are communicated through a communication port 19 provided near the lower end of the . In addition, the pressure oil communication passage 1 in the piston rod 10
1 opens into the hydraulic oil chamber 16 on the piston bottom side. Therefore, both the hydraulic oil chambers 15 and 16 communicate with each other through the pressure oil communication passage 11 and the communication port 19 within the piston rod 10. The counter cylinder 7 has a cylinder body 20 fixed to the center block 2.

In the figure, reference numeral 21 indicates a flow path switching valve disposed on the upper surface of the center block 2.
The clamp cylinder is switched between a clamp state and a clamp release state by the switching operation.

In the work clamp device having such a configuration, when the fixing bolt between the clamp block 4 and the center block 2 is loosened in order to adjust the mounting position of the clamp block 4, the counter cylinder 7
Both hydraulic oil chambers 15 and 16 in the piston rod have the same pressure, and the pressure-receiving area of the bottom-side hydraulic oil chamber 16 is larger than the pressure-receiving area of the head-side hydraulic oil chamber 15 by the cross-sectional area of the piston rod 10. Since it is wider, part of the weight of the clamp block 4 is absorbed by the difference in hydraulic pressure. This prevents the clamp block 4 from falling suddenly. When the clamp block 4 is moved up and down, the piston 14 is moved lightly because both hydraulic oil chambers 15 and 16 in the counter cylinder 7 are communicated with each other through the hydraulic oil communication passage 11 and the communication port 19 in the piston rod 10. The clamp block 4 can be moved to a desired position.
During this movement, a slight difference in volume will occur between the bottom-side hydraulic oil chamber 16 and the head-side hydraulic oil chamber 15. It will be adjusted by the inflow and outflow of oil. After fixing the clamp block 4 to the center block 2, switch the flow path switching valve 21,
When hydraulic oil is supplied to the counter cylinder 7, the hydraulic oil passes through the communication port 19, the hydraulic oil communication passage 11 in the piston rod 10, the pressure oil passage 12 in the connecting block 13, and then flows into the pressure oil passage 6 of the clamp block 4.
This will cause the clamp cylinder 5 to operate.

In this case, a flow path restrictor 22 such as an orifice is provided in the communication portion between the pressure oil communication passage 11 and the bottom side hydraulic oil chamber 16 in the piston rod 10, so that both the hydraulic oil chambers 15 and 16 are connected to the restriction passage 23. They may be communicated.

In addition, the pressure oil communication passage 11 is connected to the bottom side hydraulic oil chamber 16.
It is also conceivable that the head side hydraulic oil chamber 15 and the bottom side hydraulic oil chamber 16 are communicated only through the throttle passage 23 without communicating with the head side hydraulic oil chamber 15 and the bottom side hydraulic oil chamber 16.

FIG. 4 shows another embodiment of the counter cylinder 7, which consists of a double rod type cylinder,
A connecting block 13 is fixed to each piston rod 10 that protrudes upwardly and downwardly from a cylinder body 20, and the piston 14 is provided with a throttle passage 23 and a check valve 24 that communicate the two hydraulic oil chambers 15 and 16. This check valve 24 is assembled so that hydraulic oil can flow from the head side oil chamber 15 to the bottom side oil chamber 16 during lifting work of the clamp block 4.

In each of the above embodiments, the cylinder body 20 is fixed to the center block 2 and the clamp block 4 is fixed to the piston rod 10. It may be fixed. In this case, the pressure oil communication passage 11 of the piston rod 10 is communicated with the pressure oil supply passage 18, and the pressure oil supply/discharge port 17 provided in the cylinder 7 is communicated with the single acting cylinder 5 for clamping.

<<Effects>> In this invention, the clamp block, which is arranged in a manner that it can be raised and lowered relative to the center block,
Supported by a counter member consisting of a fluid pressure cylinder,
A working fluid flow path to the clamp cylinder is formed in the piston rod of this fluid pressure cylinder, and of the two working fluid chambers partitioned by the piston, the working fluid chamber has a fluid supply/discharge port of the fluid pressure cylinder open. The piston rod communicates with the working fluid passage in the piston rod, and the two working fluid chambers communicate with each other, so the working fluid supply and drainage passage to the clamp cylinder is not exposed to the outside, and the working fluid supply and discharge passage can be accessed with a tool. will no longer cause damage to the As a result, the processing area can be maintained wide.

Further, since only one switching valve for switching the clamp cylinders is required for each center block, all the clamp cylinders can be switched and operated at the same time, and the clamping time can be shortened.

[Brief explanation of the drawing]

Figure 1 is a central vertical sectional view, Figure 2 is an external perspective view,
FIG. 3 is a longitudinal sectional view of the counter cylinder, and FIG. 4 is a longitudinal sectional view showing another embodiment of the counter cylinder. 1... Base, 2... Center block, 4...
Clamp block, 5... Clamp cylinder, 7
... Counter cylinder, 10 ... Piston rod, 11 ... Working fluid flow path, 14 ... Piston,
15, 16... Working fluid chamber, 17... Working fluid supply/discharge port, 18... Working fluid supply path, 20... Cylinder body, 23... Throttle passage, 24... Check valve.

Claims (1)

[Claims for Utility Model Registration] 1. A center block 2 is erected on a base 1, and a clamp block 4 is supported on the center block 2 via a counter means so as to be movable up and down.
In a workpiece clamping device for a horizontal machine tool, the clamp block 4 is configured to be attachable and fixed to the center block 2, and the clamp block 4 is equipped with a single-acting cylinder 5 for clamping, in which the counter means is a single-acting hydraulic cylinder 7.
A working fluid flow path 11 is formed in the piston rod 10 of this fluid pressure cylinder 7, and two working fluid chambers 15 and 16 in the fluid pressure cylinder 7 partitioned by the piston 14 can communicate with each other. A working fluid chamber 1 configured as shown in FIG.
5 and the working fluid passage 11 in the piston rod 10.
One of the working fluid chamber 15 and the working fluid passage 11, which are in communication with the working fluid passage 11, is connected to the working fluid supply passage 18, and the other is connected to the single-acting cylinder 5 for clamping. Features: Work clamp device for horizontal machine tools. 2. A work clamping device for a horizontal machine tool according to claim 1, in which a clamp block 4 is fixed to the tip of a piston rod 10 of a fluid pressure cylinder 7. 3. A work clamping device for a horizontal machine tool according to claim 1, in which a clamp block 4 is fixed to a cylinder body 20 of a fluid pressure cylinder 7. 4 Two working fluid chambers 1 in the fluid pressure cylinder 7
A work clamp device for a horizontal machine tool according to claim 1, 2, or 3 of the utility model registration claim, in which 5 and 16 are communicated through a throttle passage 23. 5 Two working fluid chambers 1 in the fluid pressure cylinder 7
5 and 16 communicate with each other through a throttle passage 23 and a check valve 24. A workpiece clamping device for a horizontal machine tool according to claim 1, 2, or 3 of the utility model registration claim.