JPS6113093A - Rotary joint - 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 [Field of Industrial Application] The present invention relates to a rotary joint that allows fluid to flow and compressed air to flow between a fixed body and a revolving body.

[Prior art]

This type of rotary joint is widely used in construction machinery consisting of an upper revolving body and an undercarriage.

Such construction machinery is equipped with a working device such as a hydraulic excavator on the upper revolving body, and an engine and an engine on the upper revolving body.
It is equipped with a hydraulic pump, compressed air pump, etc., while the lower traveling body is equipped with hydraulic equipment such as a hydraulic motor for travel, and pneumatic equipment such as a brake cylinder, and a rotary joint is installed between the upper rotating body and the lower traveling body. The hydraulic pump of the upper rotating body and the hydraulic equipment of the lower traveling body are communicated via a rotary joint, and the compressed air pump of the upper rotating body and the pneumatic equipment of the lower traveling body are communicated via a rotary joint. It is something that By operating the engine of the upper rotating body, hydraulic pressure from the hydraulic bonder in the upper rotating body can be supplied to the hydraulic equipment of the lower rotating body via the rotary joint to operate the hydraulic equipment, and the upper rotating body can also operate the hydraulic equipment. The compressed air in the body can be supplied to the pneumatic equipment of the undercarriage via the rotary joint to operate the pneumatic equipment.

A conventional rotary joint widely used in construction machinery and the like has a configuration as shown in FIGS. 4 and 5. That is, it is constructed by assembling a rotary joint for supplying fluid and a rotary joint for supplying compressed air vertically. To explain in more detail, a cylindrical spindle b is fixed to a fixed body such as a lower running body, a cylindrical body a is fixed to a rotating body, and the body a is attached to a spindle b.
It is rotatably fitted on the outside. Body a and spindle b are both divided into two vertically, upper body a2 and lower body are fixed by bolt 2, and upper spindle b2 and lower spindle b0 are fixed by bolt) h. There is. The lower body a□ is provided with a plurality of, for example ten, fluid communication ports q shifted in the direction of the rotation axis of the body a. On the other hand, a plurality of, for example io, fluid conduction paths r are provided in the lower spindle b□ in the axial direction of the spindle b, and an annular conduction groove is formed on the outer circumferential surface of the lower spindle b□.
The ten conductive paths r of the lower spindle b1 and the ten conductive holes q of the lower body a1 are communicated through the conductive grooves. A pipe (not shown) connected to a hydraulic power source is attached to the conduit q, and a pipe (not shown) connected to a hydraulic device is attached to the conduit r. Note that a plurality of seals C are arranged between the outer peripheral side surface of the lower spindle b1 and the inner peripheral side surface of the lower body a1.

The upper body a2 is provided with a plurality of, for example, five, i-vents U for compressed air, which are offset in the direction of the rotation axis of the body a. On the other hand, a plurality of 9, for example, 5 compressed air conduction passages V are provided in the upper spindle b2 in the axial direction of the spindle b, and an annular conduction groove is provided on the outer circumferential surface of the upper spindle b2, and a conduction opening U of the upper body a2 is provided. The five conduction paths V of the upper spindle b2 and the five conduction ports U of the upper body a2 are communicated through the conduction grooves. Here, the conduction path V in the upper spindle b2 is connected to the upper spindle b2.
and the fixed part of the lower spindle b1, and from this fixed part to the lower end of the lower spindle b□, that is, to the fixed body side,
A through hole p is opened in the direction of the central rotation axis of the lower spindle b1,
Five pipes W, one end of which is connected to each conductive path V via a nut, are installed in the through hole p. A piping (not shown) connected to a pneumatic device via a manifold t is attached to the other end of the pipe W, and a piping (not shown) connected to a compressed air pump is attached to the communication port U. Note that a seal j is arranged between the outer peripheral side surface of the upper spindle b2 and the inner peripheral side surface of the upper body a2.

Next, its operation will be explained. Pressure oil discharged from the hydraulic power source on the upper revolving body side passes through the piping, passes through the conduction groove q1 of the lower body a1 of the rotary joint, the conduction passage of the lower spindle b1, and passes through the piping to the fixed side (lower traveling On the other hand, the compressed air from the compressed air pump on the upper revolving body side is supplied to the hydraulic equipment of the upper rotating body through piping, the conduction port U1 of the upper body a2 of the rotary joint, the conduction groove, and the conduction path V of the upper spindle b2.
, pipe W1, manifold t, and is supplied to the pneumatic equipment on the fixed side through piping.

However, in the above-mentioned conventional rotary joint, since the air passage between the upper spindle b2 and the manifold t is connected by the pipe W, air leakage occurs at both ends of the pipe W due to vibration or poor assembly. The probability is high. Moreover, even if an air leak occurs, it is impossible to find or repair the air leak because the pipe W is inside the lower spindle b□ when the rotary joint is assembled. Since this pipe W is attached by screwing into the upper spindle b2 through a nut, the threaded part at the end of the pipe W is damaged, and the pipe W needs to be replaced with a new one when reassembling. If the tightening torque is not constant, there is a risk of damage to the pipe W, and if the tightening torque is too small, there is a risk of air leakage. In addition, in order to pass the plurality of pipes W into the lower spindle b1, it is necessary to make a large through hole p in the center of the lower spindle 6□.
Requires difficult assembly work and machining technology.

[Problem that the invention seeks to solve]

The present invention is to solve the risk of air leakage and damage caused by using the above-mentioned pipes.

Means for Solving Problem C] In order to solve the above problems, the rotary joint of the present invention has a spindle attached to the stationary side, a body attached to the rotating body side, and the body rotatably removed from the spindle. The spindle and the body are both divided into two parts in a direction perpendicular to the rotation axis, and the two divided spindles and the body are removably fitted and attached to each other, and one body has a plurality of fluid communication ports. The other body has multiple compressed air passages, one spindle has multiple fluid passages, the other spindle has multiple compressed air passages, and one spindle has multiple compressed air passages. A conduction passage is provided in communication with a plurality of compressed air passages of the other spindle, and the plurality of fluid passages of the one body facing each other are connected to the plurality of fluid passages of the spindle through an annular conduction groove. The plurality of compressed air passages of the other body facing each other and the plurality of compressed air passages of the spindle are made to communicate with each other via annular conduction grooves.

[Effect]

In the rotary joint of the present invention, compressed air is conducted within the spindle only through a conduction path formed in the spindle without passing through a pipe.

〔Example〕

Hereinafter, one embodiment of the rotary joint of the present invention will be explained in Figs. 1 to 3.
This will be explained with reference to the figures.

FIG. 1 is a longitudinal sectional view of a rotary joint, in which the body 1 is fixed to a frame 17 of a rotating body, and the spindle 2 is fixed to a frame 17 of a traveling body, similar to the conventional example shown in FIGS. 4 and 5.
Fixed. The cylindrical spindle 2 is divided into two parts: a lower spindle 2a on the stationary side (near the traveling body) and an upper spindle 2b on the rotating body side, and the upper spindle 2b has a smaller diameter than the lower spindle 2a. The position of the upper spindle 2b is determined by fitting it into the lower spindle 2a from above, and the upper spindle 2b is fixed by screwing with a plurality of bolts 13 from the upper end thereof. A cylindrical body 1 is divided into two parts: a lower body la closer to the stationary side (traveling body) and an upper body ib closer to the rotating body side, and is rotatably fitted onto the spindle 2. The upper and lower bodies are assembled using a plurality of bolts, and a plurality of balls 5 are arranged between the inner peripheral surface of the body 1 and the outer peripheral surface of the spindle 2. The balls 5 are arranged one above the other, the upper ball 5 being supported by a washer 6 fixed to the spindle 2 with a port 7, and the lower ball 5 being supported by a collar 4.

The lower body 1a has a plurality of fluid communication ports 1, for example, seven fluid communication ports 1.
9 are provided offset in the direction of the rotation axis of the body 1, and the inner peripheral surface of the body 1 which contacts the nozzle spindle 2 of each conductive port 19 is provided with a groove 24 that goes around the inner peripheral surface. On the other hand, the lower spindle 2a is provided with the same number of fluid passages 2o as the passage ports 19 in the axial direction of the spindle 2, and the ends of each passage 2o are opened on the outer periphery of the lower spindle 2a toward the opposing conductor 019. are doing.

Then, the lower spindle 2a is inserted through the groove 27 of the lower body 1a.
The respective conductive paths 20 and the respective conductive ports 19 of the lower body 1a are communicated with each other. A pipe (not shown) connected to a hydraulic power source is attached to the conduction port 19, and a pipe (not shown) connected to a hydraulic device is attached to the connection port 21 of the conduction path 20. ``A plurality of seals 3 are arranged between the outer circumferential side of the lower spindle 2a and the inner circumferential side of the lower body la to maintain the hydraulic pressure between the communication port 19 and the conducting path side.

The upper body Ib is provided with a plurality of, for example four, compressed air communication ports 22 shifted in the direction of the rotation axis of the body 1,
A groove 25 is provided on the inner circumferential surface of the body l, which contacts the spindle 2 of each conductive port 22, and extends around the inner circumferential surface. On the other hand, the upper spindle 2b is provided with the same number of compressed air passages 23 as the passage ports 22 in the axial direction of the spindle 2, and one end of each passage 23 faces toward the opposing passage port 22, and the outer periphery of the upper spindle 2b. The other end thereof reaches the lower end surface of the upper spindle 2b. The respective conductive passages of the upper spindle 2b are communicated with the respective conductive ports 22 of the upper body 1b via the grooves 25 of the upper body 1b. Lower spindle 2
aK is each conductive path 2 reaching the lower end surface of the upper spindle 2b
The same number of conductive paths as the conductive paths 23 are provided in the axial direction of the spindle 2 from the upper end surface that comes into contact with the conductive paths 2.
4 has reached the lower end of the lower spindle 2a. Each conduction path 23 of the upper spindle 2b and each conduction path 2 of the lower spindle 2a
An O-ring 14 is provided between the conductive path 23.
Airtightness is maintained for 24 hours. In addition, the upper spindle 2b
A plurality of soles 11 are arranged between the outer peripheral side surface of the upper body 1b and the inner peripheral side surface of the upper body 1b, and airtightness between the conductive path 23 and the conductive port 22 is also maintained. Then, a pipe (not shown) connected to the compressed air pump is attached to the conduction port 22, and a pipe (not shown) connected to the pneumatic equipment is attached to the connection port 25 of the conduction path 24.

Next, its operation will be explained. Pressure oil discharged from the hydraulic power source on the upper revolving body side passes through piping, and passes through the communication port 19 of the lower body 1a of the rotary joint, the communication groove 27, and the lower spindle 2a.
It is supplied to the hydraulic equipment on the fixed side (lower traveling body) through the conduit passage 20 and the piping. On the other hand, the compressed air from the compressed air pump on the upper revolving structure side passes through the pipes to the communication port 22 of the upper body lb of the rotary joint, the communication groove 25. It is supplied to the pneumatic equipment on the fixed side through the conduit passage 23 of the upper spindle 2b, the conduit passage 24 of the lower spindle 2a, and the piping.

〔Effect of the invention〕

As is clear from the configuration and operating state of the above embodiments,
According to the rotary joint according to the present invention, the compressed air conduit is
Since both the spindle on the side of the rotating body and the spindle on the stationary side which are divided into two are connected to each other, a large hole for passing multiple pipes through the spindle on the stationary side is drilled and the pipes are arranged. There is no need to communicate. There is a conduction path 2 in place of the need to drill a large through hole in the spindle.
4 in the spindle 2a. Furthermore, if there is no need to use the pipe, there is no need to manage the tightening torque for screwing in the pipe when installing the pipe, eliminating the risk of damage to the pipe or air leakage, and of course eliminating the need to replace the pipe during reassembly. In the case of the present invention, an O-ring (1
b is arranged, there is little air leakage and reliability is high. In the unlikely event that an air leak occurs due to a defective O-ring, the rotating body spindle can be removed by simply removing the bolts that secure the rotating body side spindle to the stationary side spindle, making it easy to find the defective location. Can be repaired. Conversely, when attaching the rotating body side spindle to the stationary side spindle,
Since the bolts are bolted together after fitting, the concentricity of both spindles provides good accuracy as a rotating body. Furthermore, since the rotating system spindle does not require a structure for attaching pipes, it has a simple shape, and it is easy to perform surface treatment such as plating to prevent rust. It is also easy to apply.

In the above embodiment, compressed air was communicated between the rotating body evacuating spindle and the rotating body accommodating body, and fluid (pressure oil) was communicated between the stationary side phasing spindle and the stationary side phasing body, but the reverse may be used. However, in general, a conduit for compressed air has a smaller diameter than a conduit for fluid such as pressure oil, and the structure of the embodiment allows the diameter of the spindle and body closer to the rotating body to be smaller.

[Brief explanation of drawings]

1 to 3 show a rotary joint according to an embodiment of the present invention, FIG. 1 is a longitudinal sectional view of the whole, and FIG.
3 is a sectional view taken along the line m--m in FIG. 1. FIG. 4 and 5 show an example of a conventional rotary joint, with FIG. 4 being a longitudinal sectional view of the whole, and FIG. 5 being a sectional view taken along line V-V in FIG. 4. 1...Body, la...Lower body, lb.
...Upper body, 2a...Lower spindle, 2b...
・Upper spindle, 19...Conducting port, 20...Conducting path, 22...Conducting port, 23.24...Conducting path, part, 2
7...Groove.

Claims (1)

[Claims] A spindle is attached to the fixed side, a body is attached to the rotating body side, and the body is rotatably fitted onto the spindle, and both the spindle and the body are divided into two in a direction perpendicular to the rotation axis, and the body is divided into two A spindle and a body are removably fitted and attached to each other, one body is provided with a plurality of fluid communication ports, the other body is provided with a plurality of compressed air communication ports, and one spindle is provided with a plurality of fluid communication ports. a plurality of compressed air conduit passages in the other spindle; a plurality of compressed air conduit passages in one spindle are provided in communication with a plurality of compressed air conduit passages in the other spindle; The plurality of fluid passages of the other body and the plurality of fluid passages of the spindle are communicated with each other via annular conduction grooves, and the plurality of compressed air passages of the other body and the plurality of fluid passages of the spindle face each other. A rotary joint characterized in that the compressed air conduction passages are connected to each other through annular conduction grooves.