JPS5920913Y2 - Clamp device with built-in pressure increase mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a clamping device having a built-in pressure increasing mechanism for fixing a spindle head sliding along a column to a column in, for example, a machine tool.

In a machine tool equipped with a column movable on the sliding surface of a bed and a spindle head that moves on the sliding surface of the column, after the column and the spindle head are positioned at a predetermined position, when cutting is performed. It is necessary to fix the column or the spindle head to the bed or column, respectively, and take care to prevent them from moving due to cutting force.

For this reason, conventionally, a hydraulic clamp device has been used to clamp the movable side and the stationary side at the same time.

That is, in FIG. 1, the sliding member 11 on the movable side, such as a spindle head, can move on the sliding surface of the slideway 12 on the column side in a direction perpendicular to the drawing.

A clamping device is incorporated into the sliding member 11.

The configuration of this glue/lamp device is shown in Figure 1.

That is, a rod 113 movable in a direction perpendicular to the sliding direction of the sliding member 11 is loosely engaged with the sliding member 11.
A clamp plate 114 that abuts one side surface of the sliding member 11 and the fixed member 12 is inserted through the left side, and a nut 115 that is screwed onto the rod 1]3 is provided on the left side of the clamp plate 114.

A first cylinder 116 corresponding to the clamp plate 114 is provided on the right side of the rod 113 so as to be inserted therethrough.

The first cylinder 116 is provided with a piston 117 that is loosely engaged with the rod 113 and has a small diameter stepped portion 117a that slides inside the first cylinder 116.

The first pressure chamber A is composed of a first cylinder 116 and a piston 117.

Furthermore, on the right side of the stepped screw I/N 117 is the stepped portion 117.
A second cylinder 118 is provided which is engaged with the rod 113 and is also inserted through the rod 113.

is slidably engaged with the cylinder of the second cylinder 118;
A lid body 119 is provided which is inserted through the rod 113.

The second pressure chamber B is constituted by the end face of the first piston 117, the second cylinder 118, and the lid 119.

An oil passage 121 is provided in the right shaft of the rod 113, and is connected to the first pressure chamber A through the gap between the first piston 117 and the rod 113.
and the first pressure chamber B by supplying pressure oil to the second pressure chamber B.
Cylinder pressure receiving area x pressure and second cylinder pressure receiving area x
The sum of the pressures is given as the clamping force.

Further, in order to release the clamp on the spindle head, etc., the supply of pressure oil to the oil passage 121 is cut off, and the pressure oil in the first pressure chamber A and the second pressure chamber B is released to the tank side.

However, in the example described above, the required clamping force is provided by supplying pressure oil to the first pressure chamber A and the second pressure chamber B, but now that heavy cutting is being done, a more powerful lamp device is desired. was.

The present invention was made in view of the conventional drawbacks, and its purpose is to be able to self-fill hydraulic oil even if oil leaks from the cylinder on the pressure increasing side during clamping, and to reduce the pressure without leaving any residual pressure when unclamping. An object of the present invention is to provide a clamping device with a built-in pressure increasing mechanism.

Hereinafter, an embodiment of the clamping device of the present invention will be described with reference to FIG. 2.

The sliding member 11 on the spindle head side is a slideway (hereinafter referred to as a fixed member) on the column side.

) 12 in the vertical direction in the drawing, and a clamping device 13 built into the sliding member 11 clamps or unclamps the sliding member 11 to the fixed member 12 when necessary.

The clamp device 13 will be explained below.

A rod 14 is loosely engaged with the sliding member 1, and a collar 15 that abuts one side of the sliding member 11 and the fixed member 12 is loosely engaged with the left side of the rod 14, and is pushed to the left by a nut 16. Movement is restricted.

On the right side of the rod 14 are a first cylinder 17, a piston 19, and a second cylinder that are in contact with the other side surfaces of the sliding member 11 and the sliding member 12.
The cylinder 22 and the lid 24 are arranged in this order, and a nut 25 restricts their movement to the right.

Further, springs 31 and 32 that contact the sliding member 11 are arranged on the facing surfaces of the I-flange 15 and the first cylinder 17 to assist the operation during unclamping.

The piston 19 is a pressure increasing screw 1 consisting of a large diameter part 19a and a small diameter part 19b.
are fitted into the large inner diameter portion of the first cylinder 17 and the small inner diameter portion of the second cylinder 22 via O-rings 20 and 21, respectively.

A first pressure chamber A is formed by the large inner diameter portion of the first cylinder 17 and the large diameter portion 19a of the piston 19, and the end face of the piston small diameter portion 19b, the small inner diameter end of the second cylinder 22, and the lid body 24 form a first pressure chamber A. A second pressure chamber B is formed by this.

The lid body 24 fits into the large inner diameter portion on the right side of the second cylinder 22 via an O-ring 23 provided on its outer circumferential surface, and the portion facing the second pressure chamber B has a large recess on the bottom surface. .

Furthermore, a check valve 28 is provided on the lid body 24 in parallel to the axial direction of the rod recess 4, and the quantity valve 28 is a known valve consisting of a steel ball 28a, a spring 28b, and a plug 28C.

The second cylinder 22 has a hole 26 parallel to the axis of the rod 14.
The hole 26 has a small diameter portion inserted into the ball 2.
A shaft 26a that can be joined to the shaft 26a is inserted into the shaft 26a.

On the right side of the rod 14 is a hole 2 extending along the axis from the end.
9 is opened, the hole 29 passes through the first pressure chamber A, and the lid body 24
A hole 30 communicating with the second pressure chamber B is bored in the hole 30 .

The hydraulic circuit configuration for operating the clamp device 13 described above is as follows.

Pressure oil from a pressure oil supply source 33 is supplied to pipes 35 and 3 on one side.
8, the two-way valve 34 and the pressure switch 36 to ':jL29, and the other side is connected to the check valve 28 via the check valve 39 via the piping 38.

The hydraulic oil in the second pressure chamber B can be collected into an oil tank 37 via a pipe 40 connected to the hole 30 and a shutoff valve 41 on the way.

Next, the operation of this embodiment will be described.

First, it is necessary to fill the second pressure chamber B with hydraulic oil.

That is, when the shutoff valve 41 is energized and opened, the two-way valve 34 is turned OFF, and pressure oil is supplied from the supply source 33 to the pressure chamber A to move the piston 19 to the right, the large diameter portion 19 of the piston 19 The end a presses the shaft 26a,
In conjunction with this, the steel ball 28a is pushed back to the right against the spring 28b, thereby opening the check valve 28.

Therefore, pressure oil from the hydraulic oil supply source 33 flows into the second pressure chamber B via the check valve 39 and the check valve 28.

At this time, the shutoff valve 41 is switched to closed, and the two-way valve 34 is closed.
is turned on to open the pressure oil in the first pressure chamber A to the oil tank 37 side.

Due to the flow of hydraulic oil into the second pressure chamber B, the piston 19 moves to the left in the drawing, and along with this movement, the shaft 26a and the piston 19 are separated, and the check valve 28 is moved by the spring 28.
b is pressed and closed, and the supply of hydraulic oil to the second pressure chamber B side is stopped.

By the above operations, filling of the second pressure chamber B with hydraulic oil is completed.

Note that if this operation is performed before operating the device, it is not necessary thereafter unless there are special circumstances.

In order to clamp the sliding member 11 at a predetermined position on the slideway 12, the two-way valve 34 is operated to supply pressure oil to the first pressure chamber A, pressurize the first pressure chamber A, and supply pressure oil to the second pressure chamber A. Pressure chamber B
This is done by increasing the pressure on the side and pressing the first cylinder 17 toward the stopper 15 with reference to the nut 25.

To unclamp, the supply of hydraulic oil from the supply source 33 is stopped, the two-way valve 34 is switched, and the first pressure chamber A is opened.

At this time, when the pressure switch 36 detects that the pressure in the pressure chamber A has reached a predetermined low pressure, the shutoff valve 41 is opened to remove the residual pressure in the second pressure chamber B.

At this time, due to the auxiliary action of the springs 31 and 32, the contact surfaces of the sliding member 11, the fixed member 12, and the stopper 15 and the contact surfaces of the first cylinder 17, the sliding member 11, and the fixed member 1
A slight clearance is created between the abutting surfaces of the sliding member 11 and the sliding member 11, allowing the sliding member 11 to move easily.

If hydraulic oil leaks from the second pressure chamber B, hydraulic oil is supplied to the second pressure chamber B during unclamping.

That is, when the hydraulic oil in the second pressure chamber B decreases, the piston 19 moves to the right due to the hydraulic oil in the pressure chamber A and presses the shaft 26a, opening the check valve 28. 39, hydraulic oil is supplied to the pressure chamber B, and the piston 19 moves to the left, causing the piston 19 and the shaft 26
When the engagement with the second pressure chamber B is released, the check valve 28 closes and the flow of hydraulic oil is stopped, and the filling of the second pressure chamber B with the hydraulic oil is completed.

As mentioned above, the clamping device of the present invention is stronger than conventional clamping devices and provides a ramping force, and the shutoff valve directly connected to the pressure intensifying chamber allows for quick unclamping without leaving any residual pressure. can be done.

[Brief explanation of drawings]

FIG. 1 shows a conventional clamp device, and FIG. 2 shows a hydraulic circuit and cross-sectional structure of the clamp device of the present invention. 11, 12...Sliding member, 13...Clamp device, 14...Cylinder rod, 15...
... Stopper, 17 ... First cylinder, 22 ... Second cylinder, 28 ... Check valve, 19 ... Piston, 33 ...・・・・・・
・Supply source, 34... Two-way valve, 36...
・Pressure switch, 37...Oil tank, 3
9...Check valve, 41...Shutoff valve.

Claims (1)

[Scope of Claim for Utility Model Registration] A hydraulic clamp device for fixing and releasing a sliding member sliding on a fixed member, provided on the sliding member side and movable in a direction perpendicular to the sliding direction a rod, a stopper that is inserted through the rod and can abut on both the sliding part and the fixed member at the same time, and a stopper that is also on the other side of the rod and that is inserted through the rod and moves together with the stopper. and a first cylinder capable of holding the fixing member; a stepped piston having a large diameter portion and a small diameter portion that is inserted through the rod and slidable within the first cylinder; and the rod. a second cylinder that is inserted through the rod and has a small diameter hole on one side that engages with the small diameter portion of the piston and has a cylinder formed on the other side, and a second cylinder that is inserted through the rod and has a large diameter portion of the second cylinder a lid that engages; a member that restricts movement of one side of the lid; a first pressure chamber configured by the first cylinder and the piston; a small inner diameter portion of the second cylinder; a second oil chamber configured by an end face of the small diameter portion and the lid; a hole provided in the second cylinder parallel to the axis of the rod; a shaft slidably provided in the opening; a first check valve that is provided and opened and closed by the shaft that is moved by being pressed by the piston; and a first check valve that supplies pressurized oil to the first pressure chamber from inside the rod via a directional control valve during clamping; Pressure oil is supplied to the second pressure chamber via a second check valve that prevents backflow, and when unclamping, the pressure oil in the first pressure chamber is released to the tank side via the directional control valve, and the pressure oil is released to the tank side via the directional control valve. A clamp device with a built-in pressure increase mechanism consisting of a hydraulic circuit that releases the pressure oil in the two pressure chambers to the tank side via a shut-off valve.