JPH091408A - Rotating cylinder - Google Patents

Abstract

PURPOSE: To shorten the overall length dimension of a cylinder, by compactly assembling and matching a pilot check valve and a relief valve, even when a not so much dimensional difference exists between piston and rod diameters. CONSTITUTION: A pilot check valve 29 and a relief valve 30 are assembled so as to be positioned in the same plane orthogonal to a cylinder shaft line in the inside of the rear wall member 3 of a cylinder main body. A pair of housing holes 31, each one end of which is opened to the rear wall member 3, are boredly provided in parallel at a position receding by 180 deg.. The valves 29 and 30 are housed in series on the same shaft line into the respective holes 31. The discharge port 34 of the valve 30 is faced to the opening of the holes 31 to recover drain in the valve 30 into the inside of a housing 14 from the outer peripheral surface of the rear wall member 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary cylinder for operating a chuck attached to a machine tool such as a lathe, and more particularly to a pilot check valve and a relief valve for maintaining safety when a pressure abnormality occurs. It relates to a structure for assembling.

[0002]

2. Description of the Related Art In a conventional rotary cylinder, as shown in FIG. 4, a piston chamber 62 is formed inside a cylinder body 61 which rotates integrally with a chuck (not shown), and a piston 63 is formed in the piston chamber 62. It is slidably accommodated. A hollow rod 64 projects forward and backward from the piston 63, a front side portion thereof penetrates a front wall portion 65 of the cylinder body 61, and a rear side portion thereof penetrates a shaft portion 66 of the cylinder body 61. A distributor 67 is provided on the outer periphery of the shaft portion 66 with a bearing 68.
Is relatively rotatably inserted through and has a housing 69 fixed to the outer periphery thereof. The distributor 67 is provided with a hydraulic oil passage 70 and a lubricating oil discharge passage 71.
The drain flowing out of the No. 1 is collected inside the housing 69.

The housing 69 has a hydraulic oil supply / discharge port 7
3 are provided in a pair and are connected to the piston chamber 62 via the passage 70 of the distributor 67 and the oil passage 74 of the cylinder body 61. A pilot check valve 75 is provided in the middle of the oil passage 74 in parallel with the cylinder axis to prevent the reverse flow of the working oil from the piston chamber 62 when the supply pressure of the working oil is abnormally lowered due to a power failure or an oil leak. It is designed to prevent the hydraulic oil from being contained in the piston chamber 62. Further, a relief valve 76 is attached to the piston 63 in parallel with the cylinder axis line, and when the hydraulic oil pressure in the piston chamber 62 becomes abnormally high due to heat generation or the like, the hydraulic oil is supplied from one piston chamber 62 to the piston 63. It escapes to the other side. Therefore, if this chuck is equipped with this rotating cylinder, even if abnormal pressure occurs on the cylinder side,
The chuck can be safely operated, for example, the reduction of the gripping force of the chuck claw can be surely prevented.

[0004]

However, according to the conventional rotary cylinder, since the relief valve 76 is assembled to the piston 63, the diameter of the piston 63 and the rod 6 are reduced.
When there is not much difference with the diameter of No. 4, the relief valve mounting space cannot be secured, and therefore it is necessary to unnecessarily increase the piston diameter or, conversely, design the rod diameter too small. Therefore, there is a disadvantage that the degree of freedom in designing the piston 63 and the rod 64 is reduced. Further, since the relief valve 76 moves together with the piston 63, it is necessary to provide holes 77 and 78 into which the relief valve 76 fits before and after the piston chamber 62, which causes a problem that the number of machining steps for the cylinder body 61 increases. Further, since the pilot check valve 75 is provided in the cylinder body 61 in parallel with the cylinder axis, there is a problem that the total length of the cylinder becomes long.

Therefore, the object of the present invention is to improve the degree of freedom in designing the piston and the rod by improving the assembly structure of the pilot check valve and the relief valve.
An object of the present invention is to provide a rotary cylinder that can easily process a cylinder body and can reduce the overall length dimension of the cylinder.

[0006]

In order to solve the above problems, a rotary cylinder according to the invention of claim 1 has a pilot check valve for containing a working fluid in a piston chamber when an abnormally low pressure occurs, and a working fluid when an abnormally high pressure occurs. And a relief valve for escaping from the piston chamber, the relief valve is assembled inside the cylinder main body, and a drain recovery housing covering the outer peripheral surface of the cylinder main body is attached so as to be rotatable relative to each other.
The relief valve is configured so that the discharge port is opened inside the housing to the outer peripheral surface of the cylinder body.

According to the second aspect of the present invention, the rotary cylinder has a shaft portion projecting from the rear side of the cylinder body, the distributor is attached to the outer periphery of the shaft portion so as to be relatively rotatable, and the housing is fixed to the distributor. Configured.

A rotating cylinder according to a third aspect of the present invention comprises a pilot check valve for containing a working fluid in the piston chamber when an abnormally low pressure is generated, and a relief valve for letting the working fluid escape from the piston chamber when an abnormally high pressure is generated. The relief valve is installed inside the cylinder body so that it is located in the same plane orthogonal to the cylinder axis, and a drain recovery housing that covers the outer peripheral surface of the relief valve is attached to the cylinder body so that it can rotate relatively. Is opened inside the housing to the outer peripheral surface of the cylinder body.

According to another aspect of the present invention, the rotary cylinder has a storage hole having one end opened in the cylinder body, and the pilot check valve and the relief valve are stored in series in the storage hole on the same axis line. The discharge port of is exposed to the opening of the storage hole.

[0010]

According to the invention of claim 1, since the relief valve is assembled inside the cylinder body, the piston and the rod can be freely designed regardless of the relief valve. Further, since the relief valve is not provided in the piston, the shape of the piston chamber is simple and the cylinder body can be easily processed. Moreover, since the discharge port of the relief valve opens on the outer peripheral surface of the cylinder body, the drain of the relief valve can be directly collected in the housing without providing a dedicated drain passage in the cylinder body.

According to the second aspect of the present invention, since the housing is rotatably assembled to the cylinder body by using the distributor, the rotation supporting member such as a bearing is omitted between the housing and the cylinder body. The number of parts can be reduced.

According to the invention of claim 3, since the pilot check valve and the relief valve are compactly assembled in the same plane that is orthogonal to the cylinder axis inside the cylinder body, the space occupied by each valve in the cylinder axis direction is reduced. Minimize the overall length of the cylinder.

According to the invention of claim 4, since the pilot check valve and the relief are housed in series in the housing hole,
A space for assembling each valve can be formed by a simple process of straightly forming a storage hole on the outer peripheral surface of the cylinder body.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a cylinder main body 1 of a rotary cylinder is configured by attaching a rear wall member 3 to a rear surface of a bowl-shaped member 2 with bolts 4, and the bowl-shaped member 2 is used for a spindle (not shown) such as a lathe. It is coupled and rotated integrally with a chuck (not shown) via a spindle. A piston chamber 5 is formed inside the cylinder body 1, and a piston 6 is slidably accommodated in the piston chamber 5 while being prevented from rotating by a pin 7. The piston 6 is provided with a hollow rod 8 projecting forward and backward, the front side portion thereof penetrates the front wall portion 9 of the bowl-shaped member 2, and the rear side portion thereof penetrates the shaft portion 10 of the rear wall member 3. The rod 8 is connected to the chuck via a draw bar (not shown), and the chuck claw can be opened and closed by the reciprocating movement of the piston 6.

The shaft portion 10 is integrally formed with the rear wall member 3 so as to project to the rear side of the cylinder body 1, and a distributor 12 for supplying hydraulic oil to the piston chamber 5 is provided on the outer periphery thereof via a bearing 13. Relative rotation, that is, cylinder body 1
It is inserted to allow the rotation of the. A housing 14 is fixed to the distributor 12 with bolts 15, and the housing 14 covers the outer peripheral surfaces of the cylinder body 1 and the distributor 12. A lubricating oil discharge passage 27 is provided in the lower portion of the distributor 12, and the drain flowing out from the passage 27 is collected inside the housing 14. Housing 14
A coolant collector 16 is connected to the rear side of the rod with bolts 17, and when a long work is inserted into the rod 8 for processing,
The coolant flowing out from the rear end of the rod 8 is collected by the collector 16
Will be collected. Proximity switch 1 on top of collector 16
Dog 1 with 8 attached and screwed to the rear end of rod 8.
Based on the position of 9, the stroke of the piston 6 can be detected. A seal member 28 is interposed between the front end of the housing 14 and the outer peripheral surface of the cylinder body 1 to prevent oil from leaking from the relative rotating portion. Further, a seal member 51 for preventing coolant from entering is interposed between the seal ring 50 fixed near the rear end of the rod 8 and the rear end of the housing 14.

Next, the flow passage structure of the hydraulic oil will be described. The housing 14 includes two hydraulic oil supply / discharge ports 2
0, 21 are provided, and each port 20, 21 is pilot checked through the inner peripheral groove 22 of the housing 14, the outer peripheral groove 23 and the through hole 24 of the distributor 12, the inner peripheral groove 25, and the oil passage 26 of the shaft portion 10. It is connected to the valve 29 and the relief valve 30. As shown in FIG. 2, the pilot check valve 29
The relief valve 30 is mounted inside the rear wall member 3 of the cylinder body 1 so as to be located in the same plane orthogonal to the cylinder axis. That is, the rear wall member 3 has a pair of accommodating holes 31 open at one end, which are formed in parallel with each other at a position 180 ° apart from each other, and the pilot check valve 29 and the relief valve 30 are co-axial with each accommodating hole 31. Are stored in series with each other, and are retained by a retaining ring 33. The discharge port 34 of the relief valve 30 is formed inside the housing 14 so that the discharge port 34 opens to the outer peripheral surface of the rear wall member 3.
Is adjacent to the opening. The pilot check valve 29 includes a check valve 32a arranged in the storage hole 31 and a plunger 32b slidably stored in the storage hole 31 so that the check valve 32a can be opened.

As shown in FIG. 3, one oil passage 26A of the shaft portion 10 (for convenience, a member above the cylinder axis is A,
The lower member with B) is connected to the front side of the plunger 32bA and the rear side of the plunger 32bB through a communication hole 36A and a pilot hole 37B. The other oil passage 26B of the shaft portion 10 has a communication hole 36B and a pilot hole 3
It is connected to the front side of the plunger 32bB and the rear side of the plunger 32bA via 7A. The discharge port of the pilot check valve 29A has a radial hole 38 and a cylinder body 1.
Is communicated with the front piston chamber 5 via the oil passage 39. The discharge port of the pilot check valve 29B is the axial hole 4
It is communicated with the rear piston chamber 5 via 0.

When the hydraulic oil is supplied to the supply / discharge port 20, the pilot pressure is applied to the plunger 32b.
A moves to the right in FIG. 3, the check valve 32aA opens, and the hydraulic oil flows into the rear piston chamber 5 through the oil passage 26B, the communication hole 36B, the pilot check valve 29B, and the axial hole 40. Piston 6 slides forward,
The hydraulic oil in the front piston chamber 5 is transferred to the oil passage 39 and the radial hole 3.
8, the pilot check valve 29A, the communication hole 36A, and the oil passage 26A to be discharged from the supply / discharge port 21. In this state, due to power failure or oil leak, the supply / discharge port 2
When the supply pressure of 0 is abnormally decreased, the check valve 32aB is closed to prevent the backflow of the hydraulic oil, and the hydraulic oil is enclosed in the rear piston chamber 5. Further, when the pressure in the rear piston chamber 5 becomes abnormally high due to heat generation or the like, the relief valve 30B
Opens to allow the hydraulic oil in the piston chamber 5 to escape, and the discharge port 34B
The drain is collected in the housing 14 through the opening of the storage hole 31B.

On the other hand, when hydraulic oil is supplied to the supply / discharge port 21, the plunger 3 is driven by the pilot pressure.
2bB moves to the left, the check valve 32aB opens, and the hydraulic oil flows into the front piston chamber 5 through the oil passage 26A, the communication hole 36A, the pilot check valve 29A, and the radial hole 28, and the piston 6 moves backward. The hydraulic oil in the rear piston chamber 5 is discharged from the supply / discharge port 20 through the axial hole 40, the pilot check valve 29B, the communication hole 36B, and the oil passage 26B. In this state, supply / discharge port 2
When the supply pressure of 1 is abnormally decreased, the check valve 32aA is closed to prevent the reverse flow of the hydraulic oil, and the hydraulic oil is contained in the piston chamber 5 on the front side. When the pressure in the piston chamber 5 on the front side becomes abnormally high, the relief valve 30A opens to allow the hydraulic oil in the piston chamber 5 to escape, and the drain of the discharge port 34A enters the housing 14 from the opening of the storage hole 31A. Be recovered.

As described above, according to the rotary cylinder of this embodiment, since the pilot check valve 29 and the relief valve 30 are assembled inside the rear wall member 3 of the cylinder main body 1, the valves 29 and 30 are associated with each other. Without, the diameters of the piston 6 and the rod 8 can be freely designed. Moreover,
Since the valves 29 and 30 are assembled to the rear wall member 3 in the same plane orthogonal to the cylinder axis, the space occupied by the valves 29 and 30 in the cylinder axis direction is minimized and the overall length of the cylinder is shortened. It is also possible.

Further, since the pilot check valve 29 and the relief valve 30 are not provided on the piston 6, the front and rear end surfaces of the piston chamber 5 are flat and simple, and the bowl-shaped member 2 and the rear wall member 3 are easily processed. it can. Further, since the valves 29 and 30 are housed in series in the housing hole 31, the assembly of the valves 29 and 30 can be performed by a simple process in which the housing hole 31 is bored straight on the outer peripheral surface of the rear wall member 3. The attached space can be formed. In this case, by allowing the discharge port 34 of the relief valve 30 to face the opening of the housing hole 31, the drain of the relief valve 30 can be removed from the housing 14 without forming a dedicated drain passage in the shaft portion 10 of the rear wall member 3. Can be directly collected. Since the housing 14 is rotatably assembled to the cylinder body 1 using the distributor 12, the housing 14
There is also an advantage that the number of parts can be reduced by omitting the rotation supporting member such as a bearing between the cylinder body 1 and the cylinder body 1.

The present invention is not limited to the above-described embodiments, and the configurations and shapes of the respective parts can be arbitrarily modified and embodied without departing from the spirit of the present invention.

[0023]

As described above in detail, according to the invention of claim 1, since the relief valve is assembled inside the cylinder body, the piston and the rod can be freely designed regardless of the relief valve, and the piston chamber can be freely designed. This has the excellent effect that the cylinder body can be easily machined by simplifying the shape of and the drain of the relief valve can be directly collected in the housing.

According to the second aspect of the invention, since the housing is fixed to the distributor, there is an effect that the rotation supporting member such as a bearing is omitted between the housing and the cylinder body, and the number of parts can be reduced.

According to the third aspect of the invention, the pilot check valve and the relief valve are compactly assembled in the same plane that is orthogonal to the cylinder axis inside the cylinder body, so the space occupied by the valve in the cylinder axis direction is minimized. Thus, there is an effect that the overall length of the cylinder can be shortened.

According to the invention of claim 4, since the pilot check valve and the relief are housed in series in the housing hole, a space for assembling each valve is formed by a simple process of forming the housing hole straightly. The effect is that you can do it.

[Brief description of the drawings]

FIG. 1 is a sectional view of a rotary cylinder showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a cross-sectional view showing a flow path configuration of hydraulic oil.

FIG. 4 is a sectional view showing a conventional rotary cylinder.

[Explanation of symbols] 1 ... Cylinder body, 5 ... Piston chamber, 6 ... Piston, 10 ... Shaft, 12 ... Distributor, 14 ... Housing, 29 ... Pilot check valve, 30 ... Relief Valve, 31 ... Storage hole, 34 ... Discharge port

Claims (4)

[Claims] 1. A rotary cylinder comprising a pilot check valve for containing a working fluid in a piston chamber when an abnormally low pressure is generated, and a relief valve for allowing the working fluid to escape from the piston chamber when an abnormally high pressure is generated. A rotating cylinder that is assembled and has a drain recovery housing that covers the outer peripheral surface of the cylinder body and is rotatable relative to the cylinder body, and the relief valve discharge port is opened inside the housing on the outer peripheral surface of the cylinder body. 2. The rotary cylinder according to claim 1, wherein a shaft portion is provided so as to project from the rear side of the cylinder body, a distributor is relatively rotatably attached to the outer periphery of the shaft portion, and a housing is fixed to the distributor. . 3. A rotary cylinder comprising a pilot check valve for containing a working fluid in a piston chamber when an abnormally low pressure occurs, and a relief valve for letting the working fluid escape from the piston chamber when an abnormally high pressure occurs, in which the pilot check valve and the relief valve are cylinders. Assemble inside the main body so that they are located in the same plane orthogonal to the cylinder axis, and attach a drain recovery housing that covers the outer peripheral surface to the cylinder main body so that it can rotate relative to it. A rotating cylinder that opens at the outer peripheral surface of the cylinder body. 4. A cylinder body is provided with a storage hole having one end opened, a pilot check valve and a relief valve are stored in series in the storage hole on the same axis, and the relief valve discharge port is exposed to the opening of the storage hole. The rotary cylinder according to claim 3, wherein the rotary cylinder is a hollow cylinder.