CN110778823A - Two-way air flotation rotary joint - Google Patents

Abstract

The invention discloses a bidirectional air-floating rotary joint, comprising a shaft, a floating ring, a casing, a retaining ring, at least two rows of fourth air passages, and at least two throttle holes; the fourth air passage is radially arranged inside the floating ring; One end of the four air passages is connected to the second air passage, and the other end of the fourth air passage is connected to the axial gap between the floating ring and the shaft; the orifice is axially arranged inside the floating ring; one end of the orifice is connected to the second air passage. The air passage is connected, and the other end of the orifice is connected with the radial gap between the floating ring and the shaft; the radial load and the axial load of the present invention are both supported by the air flotation, and the whole structure does not have any contact dynamic friction parts, which avoids the need for The wear debris enters the transmission medium, which can ensure that the transmission medium is clean and free from pollution; the non-contact gap sealing method is adopted, and an air film is formed between the shaft and the floating ring, which avoids the solid-phase contact friction and ensures that the rotary joint has a long service life.

Description

Two-way air flotation rotary joint

technical field

The invention belongs to the technical field of rotary joints, in particular to a bidirectional air-floating rotary joint.

Background technique

Rotary joint is a key component that transports oil, water, gas and other media to rotating equipment. It connects the medium flowing in the static pipeline to the interior of the moving parts to realize the conversion of medium transmission from static to dynamic. Rotary joints are basic mechanical parts, and their application fields cover almost all processing and manufacturing industries, including metallurgy, machine tools, power generation, petroleum, rubber, plastics, textiles, printing and dyeing, pharmaceuticals, papermaking, food processing, etc.

At present, most of the rotary joints adopt a contact seal design, which generally has the problems of large frictional resistance, short life and easy generation of wear particles of the seal, which pollute the operating environment of the equipment. The non-contact gap sealing technology refers to a sealing method in which a layer of fluid film is filled between the sealing end faces due to the action of hydrostatic pressure or dynamic pressure to force the sealing end faces to separate from each other without rigid solid-phase contact. The use of gap sealing technology can theoretically reduce the adhesive wear between metals and significantly improve the service life of the rotary joint. Such as the non-contact rotary joints of German GAT and MAIER, but rolling bearings and contact sealing components are still used in their structure, and the grinding of grease and seals in the bearings may contaminate the transmission medium and cannot meet high cleanliness. Require.

In order to solve the above problems, we have developed a two-way air-floating rotary joint.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a bidirectional air-floating rotary joint in order to solve the above problems.

The present invention realizes above-mentioned purpose through following technical scheme:

Two-way air flotation swivel, including:

A shaft; the shaft includes a small-diameter cylinder and a large-diameter cylinder that are connected to each other, and the small-diameter cylinder and the large-diameter cylinder are coaxial; the small-diameter cylinder of the shaft is provided with a first air passage;

Floating ring; the floating ring is sleeved outside the small-diameter cylinder of the shaft and forms an axial clearance fit; one end of the small-diameter cylinder of the shaft is connected to external equipment; the first end face of the floating ring forms a radial direction with one end of the large-diameter cylinder of the shaft Clearance fit; a second air passage is arranged in the floating ring;

a casing; the casing is sleeved outside the floating ring, and a third air passage is arranged in the casing; the first air passage, the second air passage and the third air passage are communicated; the gas medium passes through the third air passage, the second air passage, the first air passage in turn After the airway, output to external equipment;

retaining ring; the retaining ring is annular, the retaining ring is fixed on the casing, and the retaining ring is used to clamp the second end face of the floating ring;

At least two rows of fourth air passages; the fourth air passages are radially arranged inside the floating ring; and one end of the fourth air passage is connected to the second air passage, and the other end of the fourth air passage is in the axial direction between the floating ring and the shaft gap connection;

at least two orifices; the orifice is axially arranged inside the floating ring; one end of the orifice is communicated with the second air passage, and the other end of the orifice is communicated with the radial gap between the floating ring and the shaft.

The beneficial effects of the present invention are:

The bidirectional air-floating rotary joint of the present invention;

Radial load and axial load are supported by air flotation, and the whole structure does not have any contact dynamic friction parts, which avoids wear debris from entering the transmission medium, which can ensure that the transmission medium is clean and pollution-free; the non-contact gap sealing method is adopted, and the shaft and floating ring A gas film is formed between them, which avoids the friction of solid-phase contact and ensures that the rotary joint has a long service life.

Description of drawings

Fig. 1 is the front sectional view of the present invention;

Fig. 2 is the side view of Fig. 1;

Fig. 3 is the top view of Fig. 1;

Fig. 4 is the structural representation of the central axis of the present invention;

Fig. 5 is A-A sectional view in Fig. 4;

Fig. 6 is the structural representation of floating ring in the present invention;

Fig. 7 is A side view in Fig. 6;

Fig. 8 is B-B sectional view in Fig. 6;

Fig. 9 is the C-C sectional view in Fig. 6;

FIG. 10 is a schematic view of the structure of the housing in the present invention.

In the figure: 1. Shaft, 11. External thread, 12. Axial air inlet, 13. Radial air inlet, 14. First radial air bearing surface, 15. First axial air bearing surface, 2. Retaining ring , 21. Large hole, 22. Small hole, 23. The first air inlet hole, 24. The annular pressure equalizing groove, 25. The second radial air bearing surface, 26. The second axial air bearing surface, 27. The throttle hole, 28. Air cavity, 3. Housing, 31. First groove, 32. Tapped hole, 33. Second air inlet hole, 34. Second groove, 4. Floating ring, 5. O-ring.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings:

As shown in Figure 1-3; two-way air floating rotary joint, including:

Shaft 1; Shaft 1 includes a small-diameter cylinder and a large-diameter cylinder that are connected to each other, and the small-diameter cylinder and the large-diameter cylinder are coaxial; the small-diameter cylinder of shaft 1 is provided with a first airway;

Floating ring 4; floating ring 4 is sleeved outside the small diameter cylinder of shaft 1, and forms an axial clearance fit; one end of the small diameter cylinder of shaft 1 is connected to external equipment; the first end face of floating ring 4 is connected to the large diameter of shaft 1 One end of the cylinder forms a radial clearance fit; the floating ring 4 is provided with a second air passage;

The casing 3; the casing 3 is sheathed outside the floating ring 4, and a third air passage is arranged in the casing 3; the first air passage, the second air passage, and the third air passage are connected; the gas medium sequentially passes through the third air passage, the second air passage After the airway and the first airway, it is output to external equipment;

retaining ring 2; retaining ring 2 is annular, retaining ring 2 is fixed on housing 3, and retaining ring 2 is used to clamp the second end face of floating ring 4;

At least two rows of fourth air passages; the fourth air passages are radially arranged inside the floating ring 4; and one end of the fourth air passage is connected to the second air passage, and the other end of the fourth air passage is between the floating ring 4 and the shaft 1 The axial gap is connected;

At least two throttling holes 27; the throttling hole 27 is axially arranged inside the floating ring 4; The radial gap is connected.

In some embodiments, an external thread 11 is provided on the outer side of one end of the small-diameter cylinder of the shaft 1 , and the shaft 1 is connected with an external device through the external thread 11 .

In this embodiment, the clearance of the clearance fit is preferably in the range of several micrometers to several tens of micrometers, which is specifically determined by the structure size and bearing capacity.

As shown in Figures 4 and 5; the first air passage includes axial air holes 12 distributed along the axial direction of the shaft 1 and at least one radial air inlet hole 13 distributed in the radial direction. One end of the radial air inlet hole 13 communicated with the axial air hole 12;

As shown in Figures 6 and 9; the second air passage includes an annular pressure equalizing groove 24, an air cavity 28 and at least one first air inlet 23, the annular pressure equalizing groove 24 is arranged around the outer wall of the shaft 1, and the annular pressure equalizing groove 24 and the The other end of the radial air intake hole 13 is communicated with one end of the first air intake hole 23, and the other end of the first air intake hole 23 is communicated with the air cavity 28;

As shown in FIG. 10 ; the third air passage is the second air inlet hole 33 , and the second air inlet hole 33 communicates with the air cavity 28 .

As shown in Figures 6 and 8; the fourth air passages in at least two rows are parallel to each other; each row of the fourth air passages includes at least two air hole combinations evenly distributed around the axis of the floating ring 4, and the air hole combinations include large holes 21, Small hole 22, one end of the large hole 21 is communicated with the air cavity 28, the other end of the large hole 21 is communicated with one end of the small hole 22, the other end of the small hole 22 penetrates the inner wall of the floating ring 4, and is connected with the floating ring 4 and the shaft 1 Axial gap connection between;

As shown in Figures 6 and 7; at least two orifices 27 are evenly distributed around the axis of the floating ring 4; one end of the orifice 27 is communicated with the large hole 21 and then communicated with the second air passage. The other end of 27 penetrates through the inner wall of the floating ring 4 and communicates with the radial gap between the floating ring 4 and the shaft 1 . In this embodiment, a large hole 21 , a small hole 22 and an orifice 27 are arranged on the floating ring, and the compressed gas enters the tiny gap between the shaft 1 and the floating ring 4 through the large hole 21 , the small hole 22 and the orifice 27 A gas film is formed to prevent the shaft 1 and the floating ring 4 from contacting and rubbing. FIG. 7 shows a case where the number of orifices 27 is eight.

In this embodiment, the arrangement of the annular pressure equalizing groove 24 and the air cavity 28 is to make the gas transmission smoother;

Preferably, there are at least two radial air inlet holes 13 and first air inlet holes 23 , and they are evenly distributed around the axis of the shaft 1 .

Further preferably, the number of the first air intake holes 23 and the radial air intake holes 13 are even. FIG. 5 shows a case where there are four radial air intake holes 13 .

As shown in FIGS. 8 and 9 , the case where there are eight first air intake holes 23 is shown, and the case where each row of large holes 21 and small holes 22 is eight;

As shown in FIG. 10 ; the casing 3 is formed in a ring shape, an annular first groove 31 is provided on the inner wall of the casing 3 , and the retaining ring 2 is fixedly installed in the first groove 31 .

As shown in Figure 10; two second grooves 34 are provided on the inner wall of the casing 3, the O-ring 5 is installed in the second groove 34, and the two second grooves 34 are placed between the floating ring 4 and the casing 3, and are located at the two axial ends of the air cavity 28 respectively.

As shown in FIG. 10 ; the casing 3 is also provided with a threaded hole 32 for installing the anti-rotation rod.

Preferably, there are at least two threaded holes 32, and they are evenly distributed around the axis of the housing.

As shown in Figures 1 and 2; the shaft 1, the floating ring 4, and the housing 3 are all coaxial.

As shown in FIG. 4 , the generating positions of the first radial air bearing surface 14 and the first axial air bearing surface 15 are also shown; and an annular step is also provided on the small-diameter cylinder of the shaft 1, and the retaining ring 2 is inwardly Snap into this annular step without making contact with shaft 1.

The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and the descriptions in the above-mentioned embodiments and the description are only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and modifications fall within the scope of the claimed invention. The claimed scope of the invention is defined by the appended claims and their equivalents.

Claims (10)

1. Two-way air supporting rotary joint, its characterized in that includes:

a shaft (1); the shaft (1) comprises a small-diameter cylinder and a large-diameter cylinder which are connected with each other, and the small-diameter cylinder and the large-diameter cylinder are coaxial; a first air passage is arranged in the small-diameter cylinder of the shaft (1);

a floating ring (4); the floating ring (4) is sleeved outside the small-diameter cylinder of the shaft (1) and forms axial clearance fit; one end of a small-diameter cylinder of the shaft (1) is connected with external equipment; the first end surface of the floating ring (4) is in clearance fit with one end of a large-diameter cylinder of the shaft (1) in the radial direction; a second air passage is arranged in the floating ring (4);

a housing (3); the shell (3) is sleeved outside the floating ring (4), and a third air passage is arranged in the shell (3); the first air passage, the second air passage and the third air passage are communicated; the gas medium sequentially passes through the third gas passage, the second gas passage and the first gas passage and then is output to external equipment;

a retainer ring (2); the retainer ring (2) is annular, the retainer ring (2) is fixed on the shell (3), and the retainer ring (2) is used for clamping the second end face of the floating ring (4);

at least two rows of fourth air ducts; the fourth air channel is radially arranged inside the floating ring (4); one end of the fourth air passage is communicated with the second air passage, and the other end of the fourth air passage is communicated with an axial gap between the floating ring (4) and the shaft (1);

at least two orifices (27); the throttle hole (27) is axially arranged inside the floating ring (4); one end of the throttle hole (27) is communicated with the second air passage, and the other end of the throttle hole (27) is communicated with a radial gap between the floating ring (4) and the shaft (1).

2. The bi-directional air bearing rotary joint as set forth in claim 1, wherein:

the first air passage comprises an axial air delivery hole (12) distributed along the axial direction of the shaft (1) and at least one radial air inlet hole (13) distributed along the radial direction, and one end of each radial air inlet hole (13) is communicated with the axial air delivery hole (12);

the second air passage comprises an annular pressure equalizing groove (24), an air cavity (28) and at least one first air inlet hole (23), the annular pressure equalizing groove (24) is arranged around the outer wall of the shaft (1), the annular pressure equalizing groove (24) is communicated with the other end of the radial air inlet hole (13) and one end of the first air inlet hole (23), and the other end of the first air inlet hole (23) is communicated with the air cavity (28);

the third air passage is a second air inlet hole (33), and the second air inlet hole (33) is communicated with the air cavity (28).

3. The bi-directional air bearing rotary joint as set forth in claim 2, wherein:

the fourth air passages of at least two rows are mutually parallel; each row of fourth air passages comprises at least two air hole combinations which are uniformly distributed around the axial lead of the floating ring (4), each air hole combination comprises a large hole (21) and a small hole (22), one end of each large hole (21) is communicated with the air cavity (28), the other end of each large hole (21) is communicated with one end of each small hole (22), and the other end of each small hole (22) penetrates through the inner wall of the floating ring (4) and is communicated with an axial gap between the floating ring (4) and the shaft (1);

at least two orifices (27) are evenly distributed around the axial lead of the floating ring (4); one end of the throttling hole (27) is communicated with the large hole (21) and then communicated with the second air passage, and the other end of the throttling hole (27) penetrates through the inner wall of the floating ring (4) and is communicated with a radial gap between the floating ring (4) and the shaft (1).

4. The bi-directional air bearing rotary joint as set forth in claim 2, wherein: the radial air inlet holes (13) and the first air inlet holes (23) are at least two and are uniformly distributed around the axial lead of the shaft (1).

5. The bi-directional air bearing rotary joint as set forth in claim 4, wherein: the number of the first air inlet holes (23) and the number of the radial air inlet holes (13) are even.

6. The bi-directional air bearing rotary joint as set forth in claim 2, wherein: the outer shell (3) is annular, an annular first groove (31) is formed in the inner wall of the outer shell (3), and the retainer ring (2) is fixedly installed in the first groove (31).

7. The bi-directional air bearing rotary joint as set forth in claim 6, wherein: two second grooves (34) are formed in the inner wall of the shell (3), the O-shaped sealing ring (5) is installed in the second grooves (34), and the two second grooves (34) are arranged at the connecting position of the floating ring (4) and the shell (3) and are respectively located at the two axial ends of the air cavity (28).

8. The bi-directional air bearing rotary joint as set forth in claim 1, wherein: the shell (3) is also provided with a threaded hole (32) for installing the anti-rotation rod.

9. The bi-directional air bearing rotary joint as set forth in claim 8, wherein: the number of the threaded holes (32) is at least two, and the threaded holes are evenly distributed around the axis of the shell.

10. The bi-directional air bearing rotary joint as set forth in claim 1, wherein: the shaft (1), the floating ring (4) and the shell (3) are coaxial.

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