JP2000257783A - Swivel joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To absorb an accumulated error and impact at the time of assembling a swivel joint. SOLUTION: A swivel joint has a joint outer 10 and a joint inner 21 fitted free to rotate, a fluid passage group formed on the joint outer 10 and the joint inner 21 and connected to each other, a lower side port forming member 38 fitted on a lower end part of the joint inner 21 free to rotate and on which a flange part 41 faces against a lower end surface of the joint outer 10, a fastening member 44 fastening the lower side port forming member 38 on the joint outer 10 as a male screw part is inserted into an insertion hole 42 opened on the flange part 41 and screwed in a screw hole 43 of the joint outer 10, a seal ring 50 sandwiched between opposed surfaces of the joint outer 10 and the flange part 41 and a seal ring 49 sandwiched between the insertion hole 42 and the fastening member 44. Consequently, it is possible to absorb an accumulated error and impact by the seal rings.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swivel joint, and in particular, the conditions of a fluid to be handled are different when handling a plurality of kinds of fluids such as oil, water, air and the like, and when handling a high pressure and a low pressure fluid. The present invention relates to a vehicle suitable for use in such a case, and for example, relates to a vehicle that is effective for use in a work vehicle with a revolving body such as a vehicle for construction equipment.

[0002]

2. Description of the Related Art As a work vehicle, there is, for example, a construction machine vehicle (hereinafter referred to as a construction machine) shown in FIG. In this construction machine, a work machine 3 for performing construction work and a driver's cab 4 are mounted on a turntable 2 rotatably supported by a chassis 1, and the work machine 3 is driven by an engine 5 for driving a car. The pump is operated and controlled by the fluid pressure of the pump 7. Therefore, between the chassis 1 and the working machine 3 and the operator's cab 4, high-pressure oil for operating the working machine and positive or negative air pressure necessary for operating the vehicle are supplied via the turntable 2. It needs to be distributed. In order to meet such demands, a swivel joint 9 is interposed between the chassis 1 and the turntable 2.

In this type of conventional swivel joint, a joint outer fixed to a chassis and a joint inner connected to a turntable are relatively rotatably fitted to each other. A fluid passage is formed on the outer peripheral surface of the joint inner.
That is, pressurized oil, air, and the like move between the chassis side and the turntable side via the fitting surface between the joint outer and the joint inner.

[0004]

In the above-described swivel joint, the total length in the vertical direction increases as the number of fluid passages increases. In order to increase the number of fluid passages without increasing the overall length, a fluid joint is formed on the inner peripheral surface of the joint inner and the outer peripheral surface of the sub-joint by fitting the sub-joint to the inner peripheral surface of the joint inner. It is generally conceivable.

Here, since the sub-joint must rotate integrally with the joint outer, the sub-joint is fastened to the joint outer. As a result, the sub-joint has a dimensional error on the joint inner side and a dimensional error on the joint outer side. Will accumulate. If the joint outer, the joint inner, and the sub-joint are assembled in a state where the accumulated error remains, galling or damage occurs when the swivel joint rotates (turns). Therefore, strict control is required for the dimensional accuracy of the joint outer, the joint inner, and the sub-joint, which increases the manufacturing cost.

It is an object of the present invention to provide a swivel joint capable of absorbing a cumulative error generated when assembling a joint outer, a joint inner and a sub-joint.

[0007]

A swivel joint according to the present invention comprises a joint outer, a joint inner rotatably fitted to the joint outer, and a joint outer and a joint inner formed respectively. Fluid passages that are connected to each other;
A sub-joint rotatably fitted into one end of the joint inner and having a flange portion facing one end surface of the joint outer; and a facing surface of the joint outer inserted through an insertion hole formed in the flange portion. And a fastening member for fastening the sub-joint to the joint outer by screwing a male screw portion into a screw hole formed in the screw hole, and a positioning portion of the fastening member is provided between the fitting hole and the insertion hole of the flange portion. It is characterized by being provided with a gap and fastened.

[0008] A seal ring is interposed between the fastening member and the insertion hole.

Further, a seal ring is interposed between the joint outer and an opposing surface of the flange portion.

According to the above-described first to third means, the accumulated error in the joint outer, the joint inner and the sub-joint can be absorbed by the gap between the flange portion and the fastening portion and the gap between the joint outer and the flange portion.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In the present embodiment, the swivel joint according to the present invention is constructed on a turntable (slewing body) 2 rotatably supported by a chassis (support) 1 as shown in FIG. Work machine 3 and operator's cab 4 for performing work
Are used in construction equipment equipped with That is, the swivel joint 9 includes the chassis 1, the working machine 3, and the cab 4
High-pressure oil for operating the working machine, compressed air (referred to as air) necessary for operating the vehicle, and hot water for heating the driver's cab 4 are passed through the turntable 2. It is configured.

As shown in FIG. 1, the swivel joint 9 is provided with a joint outer 10 and a joint inner 21 which are rotatably fitted in the circumferential direction and arranged vertically. 10 is chassis 1
Side, and the joint inner 21 is fixed to the turntable 2 side.

The joint outer 10 is vertically divided and has an outer large-diameter member 11 and an outer small-diameter member 12. The outer large-diameter member 11 is integrally formed into a cylindrical shape having a large outer diameter and an inner diameter by a casting using iron as a material. The outer small-diameter member 12 is formed into a cylindrical shape having both an outer diameter and an inner diameter smaller than that of the outer large-diameter member 11 by a casting using aluminum as a material. The outer large-diameter member 11 and the outer small-diameter member 12 are opposed to each other at a lower end surface and an upper end surface in a state where they are axially aligned, and are fastened by bolts 20.

A plurality of first annular grooves (hereinafter, referred to as annular grooves for pressurized oil) 14 for flowing oil are provided on the inner peripheral surface of the large-diameter hollow portion 13 of the outer large-diameter member 11 in parallel with each other. It is arranged and each is buried integrally. Adjoining annular grooves 14 for pressure oil on the inner peripheral surface of the large-diameter hollow portion 13
A seal ring 15 is provided between them.
On the outer peripheral portion of the outer large-diameter member 11, eight oil chassis side ports 16 are opened as first body side ports. More specifically, a turning port for turning the upper cab 4, a winch port for a hydraulic motor for turning a winch hoisting drum, a vertically movable crane boom, a derrick port for a telescopic cylinder, and a power steering Three steering ports, drain ports for various valves and motors, and a return port for the pressure oil supplied to the revolving unit side. The return port is indicated by 16A in FIGS. 1 and 4, and the drain port is indicated by 16a.

On the inner peripheral surface of the small-diameter hollow portion 17 of the outer small-diameter member 12, two water annular grooves 1 are formed as second annular grooves.
8 and 18A are arranged in parallel with each other and are respectively laid down integrally. A water chassis side port 19 communicating with the water annular groove 18 is opened in the outer peripheral portion of the outer small diameter member 12, and the water chassis side port 19 is connected to a hot water pipe of the water cooling device 6 of the engine 5. In addition, the water annular groove 18A communicates with the water chassis side port 19A to form a return path for warm water.

The joint inner 21 is vertically divided and includes an inner large-diameter member 22 and an inner small-diameter member 29. The inner large-diameter member 22 is formed in a substantially cylindrical shape by a casting using iron as a material, and is rotatably fitted into the large-diameter hollow portion 13 of the outer large-diameter member 11 of the joint outer 10. A plurality of oil passages (only some of which are shown) 23 are opened in the inner large-diameter member 22, and one end of each oil passage 23 is formed in the large-diameter hollow portion 13 of the outer large-diameter member 11. Each annular groove 1 for pressure oil submerged in the peripheral surface
4 and are communicated with each other. As shown in FIG. 4, the other end of each oil passage 23 is connected to each turntable side port (only a part is shown) 24.

A hollow portion 25 for pipe insertion is formed in the cylindrical wall of the inner large-diameter member 22 in the axial direction, and a plurality of pipes 26 are inserted in the hollow portion 25 for pipe insertion. Although one pipe 26 is illustrated in FIG. 1, in the present embodiment, the pipe 26 is composed of two water pipes and three air pipes.

An upper port forming member 27 is mounted on the upper end of the inner large-diameter member 22, and a plurality of turntable side ports 28 are opened in the upper port forming member 27. Each turntable side port 28 is set so as to constitute a water channel and an air channel, and one end thereof is connected to each pipe 26. The other end of the turntable-side port 28 is connected to a heating device or a control device of the cab 4, so that hot water heated by the water cooling device 6 and air in the air tank 8 flow.

Inner large diameter member 2 of joint inner 21
An inner small-diameter member 29 rotatably fitted in the small-diameter hollow portion 17 of the outer small-diameter member 12 is coupled to the lower end surface of the lower member 2 such that the inner small-diameter member 29 is integrally rotated by a bolt 31 with a spacer 30 interposed therebetween. Have been. The lower end portion of the inner large-diameter member 22 and the upper end portion of the inner small-diameter member 29 are joined by an indigo joint 32. The inner small-diameter member 29 is formed in a substantially cylindrical shape by a casting using aluminum as a material.

A plurality of pipe insertion openings 33 are formed at the upper end surface of the ink-jet connecting portion 32 of the inner small-diameter member 29, and each pipe insertion opening 33 is formed in the hollow portion 25 for inserting a pipe of the inner large-diameter member 22. Each inserted pipe 26 is inserted from above. One end of each fluid passage 34 is connected to each pipe insertion port 33. The other ends of the two fluid passages 34 of the respective fluid passages 34 are respectively connected to the water annular grooves 18 and 18A, and the other ends of the other four fluid passages 34 serve as third annular grooves. Each is communicated with the air annular groove 36.

On the inner peripheral surface of the small-diameter hollow portion 35 of the inner small-diameter member 29, four air annular grooves 36 are arranged in parallel with each other and are integrally laid down. A seal ring 37 is fitted between adjacent annular grooves 36 on the inner peripheral surface of the small-diameter hollow portion 35. The fluid passages 34 communicate with the annular grooves 36 for air, respectively.

A lower port forming member 38 as a sub-joint is rotatably fitted in the small diameter hollow portion 35 of the inner small diameter member 29, and the lower port forming member 38 is provided with air from the chassis side to the turntable side. One port for supplying brake air, two ports for supplying brake air from the turntable side to the chassis side, and one air port for accelerator control, a total of four chassis side ports 39 are opened. ing. One end of each fluid passage 40 laid in the inner small-diameter member 29 is connected to each chassis side port 39, and the other end of each fluid passage 40 is connected to the air annular groove 36.
And are in communication with each other.

At the lower end of the lower port forming member 38, a flange portion 41 is provided so as to protrude radially outward, and four insertion holes 42 are formed in the flange portion 41 at circumferentially spaced intervals. Each is opened to penetrate in the direction. FIG.
As shown in FIG.
The male screw portion 45 formed at the tip of the fastening member 44 is fastened to the screw hole 43 formed at the lower end surface of the outer small diameter member 12. That is, the lower port forming member 38 of the joint inner 21 is connected to the outer small-diameter member 12 of the joint outer 10 by the fastening member 44 at the flange portion 41 formed at the lower end.

As shown in FIG. 2, the fastening member 44
Are male screw part 45, positioning part 46, seal ring groove 47
And a head 48. With the seal ring 49 fitted in the seal ring groove 47, the male screw 4 is inserted into the insertion hole 42 of the flange 41 from the side of the male screw 45.
When the screw 5 is screwed into the screw hole 43, the head portion 48 of the fastening member 44 is pressed against the lower surface of the flange portion 41, so that the flange portion 41 of the lower port forming member 38 becomes the outer small-diameter member 12 of the joint outer 10. In a state of being fastened by the fastening member 44. In this fastening state, the seal ring 49 fitted into the seal ring groove 47 is pressed against the inner peripheral surface of the insertion hole 42 of the flange portion 41 over the entire circumference and is in a compressed state. and the outer peripheral surface of the positioning portion 46, the gap G ₁ is formed between the inner peripheral surface of the insertion hole 42.

The fastening member 4 between the opposing surfaces of the outer small diameter member 12 and the flange portion 41 of the lower port forming member 38
A seal ring 50 is sandwiched between the inside positions of the fourth group.
Between opposed surfaces of the 2 and the flange portion 41 of the lower port forming member 38 gap G ₂ is formed.

Next, the operation will be described.

The oil discharged from the pump 7 is the outer large-diameter member 1
A plurality of oil chassis side ports 16 to a pressure oil annular groove 1
4. The pressure is fed to the turntable side port 24 through the oil passage 23 and is fed to the working machine 3 installed in the turntable 2. Return oil from the work machine 3 is returned through two oil passages. One is return of the pressure oil, which is fed from the turntable side port 24A to the oil passage 23A, the pressure oil annular groove 14A, and the oil chassis side port 16A. The other is drain oil, which is a turntable side port 2 (not shown).
The pump 7 is returned to the reservoir tank (not shown) of the pump 7 shown in FIG. 3 via the oil passage 4a, the oil passage 23a, the annular groove 14a for pressurized oil, and the oil chassis side port 16a shown in FIG.

The hot water from the water cooling device 6 is supplied to the undercarriage side port 1
9. The water is fed to the annular groove 18 for water, the fluid passage 34, the pipe 26, and the port 28 on the turntable side for water, and is supplied to the operator's cab 4 provided on the turntable 2, a control device, and the like. The hot water returned from the cab 4 to the chassis side is a water turntable side port 28A (not shown), a pipe 26A, a fluid passage 34A, a water annular groove 18A, a chassis side port 19A.
And is circulated to the water cooling device 6.

The air from the air tank 8 is supplied to the undercarriage side port 39 for air, the fluid passage 40, the annular groove 36 for air, and the fluid passage 34a, the pipe 26a (not shown) formed in the same manner as the hot water passage, and the air turn. The pressure is fed to the table-side port 28a, and is fed to a reservoir tank (not shown) provided inside the cab 4. Air is supplied from the cab 4 side to the chassis 1 side by three pipes. That is, they are air for front brake, rear brake, and accelerator control. From the cab 4 side to the chassis 1 side, turntable side ports 28b (not shown), 2
8c, 28d, pipes 26b, 26c, 26d, fluid passages 34b, 34c, 34d, annular grooves 36b, 36 for air
c, 36d (see FIG. 1), fluid passages 40b, 40c, 4
0d, the air is supplied to the undercarriage side ports 39b, 39c, 39d.

The above-described supply of oil, hot water, and air is performed smoothly even when the turntable 2 is started to rotate (turn).

By the way, the joint outer 10 and the joint inner 21 are connected to each other by a lower port forming member 38 as a sub-joint. That is, in the inner small diameter member 29 of the joint inner 21, the outer small diameter member 12 is rotatably fitted on the outer peripheral side and the lower port forming member 38 is fitted on the inner peripheral side. Therefore, the dimensional cumulative error on the joint outer 10 side and the dimensional cumulative error on the joint inner 21 side accumulate synergistically in the joint portion between the joint outer 10 and the joint inner 21 in the lower port forming member 38. In a state where the accumulated error occurs in the joint portion between the joint outer 10 and the joint inner 21, the joint outer 1
0 and the joint inner 21 are connected to the lower port forming member 38.
When they are connected by the above-mentioned operation, galling, damage, and the like occur during the rotation (turning) operation described above.

However, in the present embodiment, the accumulated error at the joint between the lower port forming member 38 and the joint outer 10 and the joint inner 21 is the gap G ₁ formed at the joint of the lower port forming member 38. ,
Is absorbed by the G _2, it is possible to prevent the occurrence of galling and damage or the like at the time of rotation operation.

That is, the flange portion 41 of the lower port forming member 38 rotatably fitted into the inner periphery of the inner small-diameter member 29 seals the lower end surface of the outer small-diameter member 12 across the lower end surface of the inner small-diameter member 29. by being sandwiched ring 50, it is opposed with a gap G ₂ as shown in Figure 2. The fastening member 44 fastening the flange portion 41 of the lower port forming member 38 by being screwed into the screw hole 43 of the outer small-diameter member 12 is positioned by fitting the seal ring 49 into the seal ring groove 47. gap G ₁ is formed between the outer surface and the inner peripheral surface of the insertion hole 42 of the part 46.

The sealing ring groove 47 of the fastening member 44
When an inertial force acts between the inner small-diameter member 29 and the outer small-diameter member 12 when the turntable 2 starts rotating or stops rotating, the seal ring 49 is fitted to the seal ring 49.
Since the impact between the outer peripheral surface of the positioning portion 46 and the inner peripheral surface of the insertion hole 42 can be reduced, the fastening member 44 and the flange portion 4 can be used when the rotation of the turntable 2 is started or stopped.
1 can be prevented from being damaged.

Further, the seal ring 50 sandwiched between the flange portion 41 and the inner small-diameter member 29 collides with the flange portion 41 and the inner small-diameter member 29 or the outer small-diameter member 12 when the rotation of the turntable 2 is started or stopped. Since the impact at the time of the collision can be reduced, it is possible to prevent the flange portion 41 and the inner small diameter member 29 from being damaged when the rotation of the turntable 2 is started or stopped.

The seal ring 50 is connected to the swivel joint 9.
Foreign matter can be prevented from entering the inside of the device.

It should be noted that the present invention is not limited to the above-described embodiment, but may be modified without departing from the scope of the invention.
It goes without saying that various changes are possible.

For example, FIG. 5, FIG. 6 and FIG.
May be configured as shown in FIG.

The embodiment shown in FIG. 5 differs from the above-described embodiment in that the seal rings 49 and 50 are formed on rectangular seal rings 49A and 50A.

The embodiment shown in FIG. 6 differs from the above embodiment in that the seal ring 49 is formed as a seal ring having a convex cross section.

The embodiment shown in FIG. 7 is different from the above-described embodiment in that a positioning portion 46 is cut off from a fastening member 44 and formed in a hollow cylindrical positioning portion 46A, and a male screw portion 45 is fastened. The point is that it is provided so as to reach the screw hole 43 of the outer small diameter member 12 directly from the head 48 of the member 44.

Any number of fastening members 44 may be provided.

The seal rings 49 and 50 can be omitted when the processing accuracy is improved.

The material forming the joint outer and the joint inner is not limited to using iron and aluminum, and other metal materials and resin materials can be used as appropriate.

[0046]

As described above, according to the present invention,
Since the dimensional error of the joint outer, the joint inner and the sub-joint can be absorbed, the dimensional accuracy of each part of the joint outer, the joint inner and the sub-joint can be relaxed, and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a swivel joint according to an embodiment of the present invention.

FIG. 2 is an enlarged view showing a portion I in FIG.

FIG. 3 is a side view showing a construction machine in which a swivel joint is used.

FIG. 4 is an external view of a swivel joint.

FIG. 5 is an enlarged view illustrating a second embodiment of the present invention and corresponding to FIG. 2;

FIG. 6 is an enlarged view corresponding to FIG. 2 showing a third embodiment of the present invention.

FIG. 7 is an enlarged view corresponding to FIG. 2 showing a fourth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... chassis, 2 ... turntable, 3 ... working machine, 4 ... cab, 5 ... engine, 6 ... water cooling system, 7 ... pump, 8 ...
Air tank, 9: swivel joint, 10: joint outer, 11: outer large diameter member, 12: outer small diameter member, 13: large diameter hollow portion, 14, 14A, 14a: annular groove for pressure oil, 15: seal ring, 16 , 16A, 16a ...
Oil chassis side port, 17 ... Small diameter hollow part, 18, 18A ...
Annular groove for water, 19, 19A ... port on water chassis side, 20 ...
Bolt, 21 joint inner, 22 inner large diameter member, 23, 23A, 23a oil passage, 24, 24A, 24
a ... turntable side port, 25 ... hollow part for pipe insertion, 26, 26A, 26a, 26b, 26c, 26d ...
Pipe, 27 ... Upper port forming member, 28, 28A, 2
8a, 28b, 28c, 28d: Turntable side port, 29: Inner small diameter member, 30: Spacer, 31: Bolt, 32: Ingot connecting part, 33: Pipe insertion port, 34,
34A, 34a, 34b, 34c, 34d ... fluid passages,
35: small diameter hollow portion, 36, 36b, 36c, 36d: annular groove for air, 37: seal ring, 38: lower port forming member (sub joint), 39, 39b, 39c, 3
9d ... chassis side port, 40, 40b, 40c, 40d ...
Fluid passage, 41: flange portion, 42: insertion hole, 43: screw hole, 44: fastening member, 45: male screw portion, 46, 46A
... Positioning part, 47 ... Seal ring groove, 48 ... Head, 4
9,49A ... seal ring, 50, 50A ... seal ring, G _1, G ₂ ... gap.

Claims (3)

[Claims] A joint outer, a joint inner rotatably fitted to the joint outer, a fluid passage formed in the joint outer and the joint inner and connected to each other; A sub-joint, which is rotatably fitted into one end of the joint inner and has a flange portion facing one end surface of the joint outer, and a sub-joint that is inserted into an insertion hole formed in the flange portion and is opposed to the joint outer surface. A male screw part is screwed into the formed screw hole, and a fastening member for fastening the sub-joint to the joint outer, and a positioning part of the fastening member is provided with a gap between the positioning part and the insertion hole of the flange part. The swivel joint is provided and fastened. 2. The swivel joint according to claim 1, wherein a seal ring is interposed between the fastening member and the insertion hole. 3. The swivel joint according to claim 1, wherein a seal ring is sandwiched between the joint outer and an opposing surface of the flange portion.