JPS61286691A - Rotary coupling for high pressure fluid - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a rotary joint for high pressure fluid.

[Prior Art] High-pressure fluid is used in hydraulically actuated liners and high-pressure cleaning liquid injection devices for removing flakes from machined parts. requires a rotary joint to connect the high pressure fluid path.

Conventionally, as such a rotary joint, for example, the Utility Model Publication No. 57-1
There is one disclosed in Japanese Patent No. 74883. In this conventional technology, a cylindrical body is pressed against the end of the passage of the rotating body by upstream fluid pressure at the butt connection of the high-pressure fluid passage between the fixed part and the rotating part to prevent leakage of high-pressure fluid from the connection part. It has become.

By the way, high-pressure fluid generators such as hydraulic pumps are equipped with relief valves to avoid abnormal pressure increases in high-pressure fluid passages, but if the passage or piping to the high-pressure operating equipment is extremely long, Even if an overload condition occurs in high-pressure equipment, the relief valve may not operate immediately due to expansion of the piping, which may cause damage to the high-pressure equipment or damage to the seals in the piping. be.

[Problems to be Solved by the Invention] In view of the above-mentioned problems, the purpose of the present invention is to provide a rotary joint with a pressure regulating valve, so that when the high-pressure operating equipment is overloaded, the pressure regulating valve operates to reduce the high-pressure operating equipment. An object of the present invention is to provide a high-pressure fluid rotary joint that immediately releases abnormal high pressure acting on the fluid.

[Means for Solving the Problems] In order to achieve the above object, the configuration of the present invention is such that the fixing member is provided with a screw shaft portion having a cylindrical portion connected to the inlet passage, and the shaft support member is screwed onto the screw shaft portion. The cylindrical portion of the fixed member is connected to the cylindrical portion of the rotating member, and the cylindrical portion of the fixed member is connected to the cylindrical portion of the rotary member through a bearing. In addition to pressing the fitted hollow piston, a pressure regulating valve is provided in the middle of the passage connecting the cylindrical portion of the fixed member and the tank.

[Function] From the inlet passage 33 of the fixed member 4 to the cylinder 8i! When the pressure of the high-pressure fluid entering 18 becomes abnormally high, it acts on the valve body 5 of the valve chamber 29 from the throttle passage 19, and the valve body 5 resists the force of the spring 7.
Push away from the valve seat. The pressure in the cylindrical chamber 18a is thus released to the tank 28 via the throttle passage 19.27, and the high-pressure operating equipment connected to the rotary member 1 with the outlet passage 21 is protected.

[Examples of the Invention] The present invention will be described based on Examples. As shown in FIG. 1, the rotary joint for high pressure fluid according to the present invention includes a fixed member 4 having an inlet passage 33 and a rotating member 1 having an outlet passage 21.
and a shaft support member 2 that rotatably supports the rotating member 1 on a fixed member 4. A cylindrical portion 18 connected to the inlet passage 33 is provided at the center of the fixing member 4, and a screw shaft portion 34 is provided concentrically with this cylindrical portion 18. Cylindrical part 18
A hollow piston 3 equipped with an O-ring 9 is fitted in the hollow piston 3, and is pressed against an end surface 24a of the shaft portion 24 of the rotating member 1 by the force of a spring 8, as will be described later.

The fixed member 1 is provided with a pressure regulating valve A. That is, 1 yen
1? lF! Throttle passage 19 and passage 2 connected to 1S18
A cylindrical valve chamber 29 is provided at the connecting portion of the valve chamber 7, into which the valve body 5 having a through hole 35 is fitted, and is pressed against a valve seat provided on the end wall of the valve chamber 29 by the force of the lever spring 7. and is configured to close the passageway 27.

The spring 7 is interposed between the spring seat 31 fitted in the valve chamber 29 and the valve body 5, and the spring seat 31 is pressed against the end of the pressure regulating bolt 6 screwed and supported by the support member 30. The valve opening pressure of the valve body 5 is adjusted by this pressure regulating bolt 6. Passage 27 is connected to tank 28 via piping.

The shaft support member 2 includes a cylindrical portion 23 at one end, and a large-diameter cylindrical portion 25 is formed from a stepped portion 25a in the central portion. Furthermore, a screw hole 26 is provided on the other end side, and this screw hole 2
The screw shaft portion 34 of the fixing member 4 is screwed into the screw shaft 6 , and the lower end of the shaft support member 2 is pressed against the end surface of the fixing member 4 via the gasket 17 . The shaft portion 24 of the rotating member 1 is supported by the bearing 16 supported by the cylindrical portion 23 and the bearing 13 supported by the large diameter cylindrical portion 25. Specifically, the bearing 13 is pressed against the stepped portion 25a by applying washers 14 and 12 to both ends thereof, and is further applied to the spacer 11 and the washer 12, and then
The retaining ring 10 is fitted onto the shaft portion 24, and the shaft portion 24 is supported so as not to move in the axial direction relative to the shaft support member 2. A cylindrical portion 22 communicating with the outlet passage 21 is provided in the same manner as the screw shaft portion 24 , and this cylindrical portion 22 communicates with the cylindrical portion 18 via the hollow piston 3 .

Next, the operation of the rotary joint for high pressure fluid according to the present invention will be explained. High-pressure fluid from the high-pressure fluid generator enters the cylindrical portion 18 from the inlet passage 33 through a pipe (not shown), exerts pressure on the lower end surface of the hollow piston 3, and
is pressed against the end surface 24a of the shaft portion 24 of the rotating member 1,
High pressure fluid is prevented from leaking from this abutting surface. IIRiFl is then passed from the cylindrical part 18 through the passage of the hollow piston 3 and the cylindrical part 22 of the rotating member 1 and from the outlet passage 21.
Sent to high-pressure operating equipment such as nozzles. For example, when a high-pressure operating device becomes overloaded due to clogging of an injection nozzle, and the fluid pressure in the cylindrical portion 18 increases, this pressure acts on the valve body 5 of the valve chamber 29 from the throttle passage 19, and the force of the spring 7 The valve body 5 is pushed down against the pressure.

Therefore, the fluid pressure in the cylindrical chamber 18a is reduced to the throttle passage 19.2.
7 and is opened to tank 28. In this way, high-pressure fluid at a substantially constant pressure is always sent to the high-pressure operating equipment, thereby preventing damage to the high-pressure operating equipment.

The pressure in the large-diameter cylindrical portion 25 of the shaft support member 2 is atmospheric pressure, and the hollow piston 3 that fits into the cylindrical portion 18 is fitted into the cylindrical portion 18 via the O-ring 9. The fluid pressure acting on the lower end of the hollow piston 3 is much greater than the atmospheric pressure acting on the stepped portion of the piston 3.

The higher the pressure of the high-pressure fluid, the more the hollow piston 3 moves toward the rotating member 1.
is strongly pressed against the end surface 24a of the shaft portion 24. spring 8
maintains the screws 1 to 3 pressed against the end surface 24a of the shaft portion 24 when the supply of high-pressure fluid to the cylindrical portion 18 is stopped. In the above-described embodiment, when the high-pressure operating equipment is overloaded, even if the pressure regulating valve A operates, the flow rate from the cylindrical portion 18 to the tank 28 is small, so the pressure acting on the high-pressure operating equipment gradually decreases. It may rise.

In the embodiment shown in FIG. 2, the high pressure fluid in the cylindrical portion 18 is discharged into the tank 28 through the bypass passage 38 when the high pressure operating equipment as described above is continuously overloaded. . The hollow piston 3 fitted into the cylinder 81Sis of the fixed member 4 has a wide annular 'a46 in the middle part.
A radial passage 43 connecting the annular groove 46 and the passage 44 is provided. Also, hollow piston 3
A throttle passage 45 is provided in the lower end wall, and a spring 8 is provided in the cylindrical chamber 18a between the lower end wall and the end wall of the cylindrical portion 18 to press the hollow piston 3 against the end surface 24a of the shaft portion 24 of the rotating member 1. is interposed, and a throttle passage 1 is provided in the cylindrical chamber 18a.
9 is connected to the pressure regulating valve A similar to the embodiment shown in FIG.
will be provided.

An axial groove 42 is provided on the outer peripheral surface of the hollow piston 3,
A ball 41, which is engaged by the force of the spring 4o, is housed in a cylindrical portion formed in the fixing member 4, and the end of the spring 40 is engaged with a bolt 39 screwed into the cylindrical portion, thereby causing the detent. Mechanism B is configured. A large-diameter cylindrical portion 25 is formed at the upper end of the cylindrical portion 18 , and the large-diameter cylindrical portion 25 is connected to the tank 28 via a bypass passage 38 .

In the embodiment shown in FIG. 2, the shaft portion 24 of the rotating member 1 is supported by a pair of bearings 16 inside a large-diameter cylindrical portion 25. As shown in FIG. Specifically, a shaft portion 24 is integrally formed at the upper end of the fixing portion 04, and a shaft support member 2 resembling a cap nut having a screw hole 2a is screwed into the shaft portion 24. The shaft portion 24 of the rotating member 1 passes through the hole 36 provided in the end wall of the shaft support member 2 and the cylindrical portion 25
A pair of bearings 13. is protruded into the interior of the cylindrical portion 25 and the shaft portion 24, with the washer 14 and the washer 12 sandwiched therebetween. f5
A spacer 11a having an O-ring 47 attached to its outer circumferential surface is fitted, and a nut 10a is screwed onto the shaft portion 24 to sandwich a pair of bearings 13 between the shaft support member 2 and the spacer 11a. The shaft portion 24 of the rotating member 1 is supported so as not to move in the axial direction.

An O-ring 15 is attached to the outer circumferential surface of the shaft portion 24 to provide a seal between the shaft portion 24 and the spacer 11a. The other configurations are the same as those of the embodiment shown in FIG. 1, and the same reference numerals are given to the same constituent members and the explanation thereof will be omitted.

In the embodiment shown in FIG. 2, the high-pressure fluid entering the passage 44 of the hollow piston 3 from the inlet passage 33 passes through the cylindrical part 22 of the rotary member 1 and is sent from the outlet passage 21 to the high-pressure operating equipment.

At the same time, the hollow screw 1-3 is passed from the passage 44 to the passage 45.
It flows into the lower cylindrical chamber 18a and exerts pressure on the lower end surface of the hollow piston 3.

Since the large diameter cylindrical portion 25 surrounding the upper end of the hollow piston 3 is at atmospheric pressure, the fluid pressure acting on the lower end surface of the hollow piston 3 causes the hollow piston 3 to press against the end surface 24a of the shaft portion 24.
This seals the leakage of high-pressure fluid from this abutting surface.

When the high-pressure operating equipment becomes overloaded, the pressure regulating valve A is activated in the same manner as in the actual flow example shown in FIG. and is opened to tank 28.

However, the flow rate of pressure fluid passing through this pressure regulating valve A is small, so it is a high pressure cloth! If the IJ equipment is continuously overloaded,
Due to the throttle effect of the throttle passage 45, the pressure of the passage 44 acting on the bottom wall of the hollow piston 3 overcomes the force of the spring 8, and the hollow piston 3 is pushed down, causing the hollow piston 3 to press down on the shaft portion 24.
A bypass passage 48 is opened away from the end surface 24a.

Therefore, from the inlet passage 33 to the passage 4 of the hollow piston 3.
The high pressure fluid that entered into tank 2 passes through bypass passage 38.
8 to protect high-pressure operating equipment.

In this embodiment, the pressure regulating valve A normally maintains the pressure to the high-pressure I71 equipment at a predetermined pressure, and when an overload condition continues, it acts as a pilot valve to lower the pressure in the cylindrical chamber 18a.
The hollow piston 3 is pushed down to open the bypass passage 38.

[Effects of the Invention] As described above, the present invention provides a fixed member having a cylindrical portion connected to the inlet passage, a passage connected to the cylindrical portion and the tank, and a pressure regulating valve disposed in the middle of this passage. When high-pressure equipment supplied with high-pressure fluid becomes overloaded and the pressure in the cylindrical part of the fixing member becomes abnormally high, the pressure regulating valve opens and the pressure is released into the tank, preventing damage to the high-pressure equipment. I can do it. In particular, by providing a pressure regulating valve on a fixed member close to high-pressure operating equipment, its operation is very quick, and when multiple high-pressure operating equipment is driven by a common high-pressure fluid generator, individual Another advantage is that the pressure of the pressure regulating valve A can be set for each high-pressure operating device.

[Brief explanation of drawings]

FIG. 1 is a side cross-sectional view of a high-pressure fluid rotary joint according to a first embodiment of the present invention, and FIG. 2 is a side cross-sectional view of a high-pressure fluid rotary joint according to a second embodiment of the present invention. A: Pressure regulating valve 1: Rotating member 2: Shaft support member 3: Hollow piston 4: Fixed member 13.16: Bearing 18: Cylindrical portion 21: Outlet passage 22: Cylindrical portion 24: Shaft portion 33:
entrance passage

Claims (1)

[Claims] A screw shaft portion having a cylindrical portion connected to the inlet passage is provided on the fixed member, a shaft support member is screwed to the screw shaft portion, and a cylindrical portion connected to the outlet passage via a bearing in a large diameter cylindrical portion connected to the cylindrical portion. A hollow piston fitted in the cylindrical portion of the fixed member is supported against the axial portion of the rotating member, and a passageway connecting the cylindrical portion of the fixed member and the tank is midway. A rotary joint for high pressure fluid, characterized by being equipped with a pressure regulating valve.