Magnetic liquid sealing structure for rotation of inner shaft and outer shaft

Abstract

The magnetic liquid sealing structure comprises the inner shaft and the hollow outer shaft, the inner shaft is inserted into the hollow portion of the outer shaft, the outer shaft is inserted into a sealing seat, and a first magnetic liquid sealing assembly is arranged between the hollow wall face of the inner shaft and the hollow wall face of the outer shaft. The inner shaft rotates relative to the outer shaft through the first magnetic liquid sealing assembly, a second magnetic liquid sealing assembly is arranged between the outer shaft and the sealing seat, and the outer shaft rotates relative to the sealing seat through the second magnetic liquid sealing assembly. The first magnetic liquid sealing assembly and the second magnetic liquid sealing assembly are arranged on the inner shaft and the outer shaft respectively, and the first magnetic liquid sealing assembly and the second magnetic liquid sealing assembly achieve the leakage prevention function when the rotating speeds of the inner shaft and the outer shaft are inconsistent through the high viscosity and the self-sealing characteristic of magnetic liquid. The problem of leakage of a traditional shaft sealing structure when the rotating speeds of an inner shaft and an outer shaft are inconsistent is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of sealing, in particular to a magnetic liquid sealing structure used for the rotation of inner and outer shafts. Background Art

[0002] Magnetic liquid seal is a new type of seal, which has advantages that ordinary seals do not have, such as zero leakage, high reliability, long life, no pollution, etc. So far, magnetic liquid seals are all single-axis magnetic liquid seals. The sealing structure in the reactor system requires double-axis sealing, and the inner shaft sleeve and the outer shaft, and the outer shaft and the sealing seat are required to be sealed. The sealing method currently used is that the inner shaft sleeve and the outer shaft are single-axis magnetic liquid seals, and the ordinary seals used between the outer shaft and the sealing seat are difficult to meet the sealing requirements; more importantly, when the speeds of the inner and outer shafts are inconsistent, radial movement will occur, resulting in circumferential and radial vibrations and failures, or oil and liquid leakage, which cannot meet the needs of high-speed, high-precision transmission and hydraulic sealing. Utility Model Content

[0003] The utility model aims to provide a magnetic liquid sealing structure for the rotation of inner and outer shafts. A first magnetic liquid sealing component and a second magnetic liquid sealing component are respectively arranged on the inner and outer shafts. The high viscosity and self-sealing characteristics of the magnetic liquid are utilized to realize the leakage prevention function when the rotation speeds of the inner and outer shafts are inconsistent, thereby solving the leakage problem existing in the traditional shaft sealing structure when the rotation speeds of the inner and outer shafts are inconsistent.

[0004] In order to achieve the above technical objectives, the utility model is implemented through the following technical solutions:

[0005] A magnetic liquid sealing structure for inner and outer shaft rotation, comprising an inner shaft and a hollow outer shaft, wherein the inner shaft is inserted into the hollow portion of the outer shaft, and the outer shaft is inserted into a sealing seat;

[0006] Wherein, a first magnetic liquid sealing component is arranged between the hollow wall surface of the inner shaft and the outer shaft, and the inner shaft rotates relative to the outer shaft through the first magnetic liquid sealing component;

[0007] A second magnetic liquid sealing component is arranged between the outer shaft and the sealing seat, and the outer shaft rotates relative to the sealing seat through the second magnetic liquid sealing component.

[0008] As a further technical solution of the magnetic liquid sealing structure, the first magnetic liquid sealing assembly includes a high-speed shaft sleeve, a high-speed shaft pole shoe assembly and a second bearing, the inner shaft passes through the high-speed shaft sleeve and is inserted into the hollow portion of the outer shaft, and the high-speed shaft pole shoe assembly and the second bearing are sequentially arranged on the outer periphery of the high-speed shaft sleeve along the axial direction of the inner shaft;

[0009] Among them, the high-speed shaft pole shoe assembly forms a magnetic liquid sealing structure between the sleeve and the hollow wall of the outer shaft, and the inner shaft is connected to the outer shaft via the second bearing. The magnetic liquid sealing structure realizes the sealing between the outer circle of the high-speed shaft sleeve and the inner hole of the outer shaft through the interaction between the magnetic field distribution inside the sealed space and the magnetic liquid.

[0010] As a further technical solution of the magnetic liquid sealing structure, the first magnetic liquid sealing assembly further includes a bearing washer, a shaft elastic retaining ring and a hole elastic retaining ring;

[0011] The shaft elastic retaining ring is arranged at the upper and lower ends of the second bearing inner ring, the hole elastic retaining ring and the bearing washer are respectively arranged at the upper and lower ends of the second bearing outer ring, and the bearing washer extends toward the high-speed shaft pole shoe assembly, through axial limitation of the second bearing and the high-speed shaft pole shoe assembly.

[0012] As a further technical solution of the magnetic liquid sealing structure, a plurality of second O-rings are arranged between the inner shaft and the high-speed shaft sleeve. The plurality of second O-rings are distributed along the axial direction of the high-speed shaft sleeve and are used to seal the outer circle of the inner shaft and the inner hole of the high-speed shaft sleeve.

[0013] As a further technical solution of the magnetic liquid sealing structure, a second skeleton oil seal is arranged below the high-speed shaft pole shoe assembly to prevent some particles or liquids from entering the pole shoe.

[0014] As a further technical solution to the magnetic liquid sealing structure, a liquid accumulation tray is arranged below the second skeleton oil seal, and an annular groove is arranged in the middle of the liquid accumulation tray. The opening of the annular groove faces the second skeleton oil seal. The leaked magnetic liquid is collected through the annular groove to prevent the magnetic liquid from losing pressure and falling into the equipment.

[0015] As a further technical solution of the magnetic liquid sealing structure, the second magnetic liquid sealing assembly includes a tube shaft pole shoe assembly and a first bearing, and the tube shaft pole shoe assembly and the first bearing are sequentially arranged between the outer shaft and the sealing seat along the axial direction of the outer shaft;

[0016] Wherein, the outer shaft is connected to the sealing seat via the first bearing, the first bearings are arranged in pairs and are tapered roller bearings, and the first bearings arranged in pairs are arranged back-to-back along the axial direction of the outer shaft to improve the axial load-bearing capacity of the first bearings;

[0017] The tubular shaft pole shoe assembly forms a magnetic liquid sealing structure between the outer shaft and the sealing seat, and the magnetic liquid sealing structure achieves sealing between the outer circle of the outer shaft and the inner hole of the sealing seat through the interaction between the magnetic field distribution inside the sealing space and the magnetic liquid.

[0018] As a further technical solution of the magnetic liquid sealing structure, a first skeleton oil seal is provided between the tube shaft pole shoe assembly and the first bearing to prevent some particles or liquids from entering the pole shoe.

[0019] As a further technical solution of the magnetic liquid sealing structure, first skeleton oil seals are respectively arranged between the upper and lower ends of the sealing seat and the outer shaft to prevent dust from entering the sealing structure.

[0020] As a further technical solution of the magnetic liquid sealing structure, the second magnetic liquid sealing assembly further includes an elastic retaining ring, a stop washer and a pipe nut;

[0021] The elastic retaining ring is used to fix the inner ring of the first bearing at the lower end, the stop washer is arranged at the inner ring of the first bearing at the upper end, the pipe nut is screwed with the outer shaft thread and presses the stop washer against the inner ring of the first bearing, and the axial load-bearing capacity of the first bearing is further improved by axially limiting the first bearing.

[0022] Compared with the prior art, the utility model has the following advantages and beneficial effects:

[0023] The utility model provides a magnetic liquid sealing structure for the rotation of inner and outer shafts. A first magnetic liquid sealing component and a second magnetic liquid sealing component are independently arranged on the inner and outer shafts, respectively. The high viscosity and self-sealing characteristics of the magnetic liquid are utilized at the rotation gap between the inner and outer shafts through the first magnetic liquid sealing component and the second magnetic liquid sealing component. The inner and outer shafts can be independently sealed even when the rotation speeds are inconsistent. This not only solves the traditional leakage problem caused by the inconsistent rotation speeds of the inner and outer shafts, but also has better pressure resistance, corrosion resistance, wear resistance and high temperature performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings described herein are used to provide a further understanding of the embodiments of the present utility model, constitute a part of this application, and do not constitute a limitation of the embodiments of the present utility model. In the drawings:

[0025] Figure 1 It is a cross-sectional structural schematic diagram of the utility model;

[0026] Figure 2 for Figure 1 Schematic diagram of the enlarged structure marked A in the figure.

[0027] Marks and corresponding parts names in the attached drawings:

[0028] 1-tube shaft, 2-first skeleton oil seal, 3-shaft seal pressure plate, 4-first O-ring, 5-seal seat, 6-tube shaft pole shoe assembly, 7-tube shaft bearing gasket, 8-first bearing, 9-fluid accumulation plate, 10-second skeleton oil seal, 11-second O-ring, 12-stop washer, 13-tube nut, 14-high-speed shaft sleeve, 15-high-speed shaft pole shoe assembly, 16-seal seat cover, 17-bearing gasket, 18-elastic retaining ring for shaft, 19-second bearing, 20-elastic retaining ring for hole, 21-expansion ring. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the utility model more clearly understood, the utility model is further described in detail below in conjunction with embodiments and drawings. The schematic implementation manner of the utility model and its description are only used to explain the utility model and are not intended to limit the utility model.

[0030] Example 1

[0031] This embodiment 1 provides a magnetic liquid sealing structure for the rotation of inner and outer shafts, such as Figure 1-Figure 2 As shown, it includes an inner shaft (not shown in the figure) and a hollow outer shaft. In this embodiment, the hollow outer shaft is a tube shaft 1, the inner shaft is inserted into the hollow part of the tube shaft 1, and the tube shaft is inserted into a sealing seat 5. The sealing seat 5 is fixedly connected to the end face of the device, and the lower end face of the sealing seat 5 and the end face of the device are also sealed by a first O-ring 4;

[0032] Among them, a first magnetic liquid sealing component is arranged between the inner shaft and the hollow wall surface of the tube shaft 1, and the inner shaft rotates relative to the tube shaft 1 through the first magnetic liquid sealing component, and a second magnetic liquid sealing component is arranged between the tube shaft 1 and the sealing seat 5, and the tube shaft 1 rotates relative to the sealing seat 5 through the second magnetic liquid sealing component.

[0033] Specifically, see Figure 1-Figure 2 As shown, the first magnetic liquid sealing assembly includes a high-speed shaft sleeve 14, a high-speed shaft pole shoe assembly 15 and a second bearing 19. The inner shaft passes through the high-speed shaft sleeve 14 and is inserted into the hollow part of the tube shaft 1. The expansion ring 21 and the set screw are used to achieve the locking of the high-speed shaft sleeve 14 and the inner shaft. The high-speed shaft pole shoe assembly 15 and the second bearing 19 are sequentially arranged on the outer periphery of the high-speed shaft sleeve 14 from bottom to top along the axial direction of the inner shaft. The high-speed shaft pole shoe assembly 15 forms a magnetic liquid sealing structure between the sleeve 14 and the hollow wall of the tube shaft 1. The magnetic liquid sealing structure uses concentric liquid "O"-shaped sealing rings arranged along the axial direction formed by magnetic liquid, permanent magnets and spacers to achieve the purpose of sealing. This is a prior art and will not be repeated here.

[0034] At the same time, the inner shaft is rotatably connected to the tubular shaft 1 via the second bearing 19, and the upper and lower ends of the inner ring of the second bearing 19 are respectively provided with shaft elastic rings 18 for fixing the inner ring of the second bearing 19, and the upper and lower ends of the outer ring of the second bearing 19 are respectively provided with hole elastic rings 20 and bearing washers 17, and one end of the bearing washer 17 extends toward the high-speed shaft pole shoe assembly 15, thereby achieving the axial limiting capability of the high-speed shaft pole shoe assembly at the same time.

[0035] Please refer to Figure 1-Figure 2 As shown, the second magnetic liquid sealing assembly includes a tube shaft pole shoe assembly 6 and a first bearing 8, which are sequentially arranged from bottom to top between the tube shaft 1 and the sealing seat 5 along the axial direction of the tube shaft 1, and the tube shaft 1 is rotatably connected to the sealing seat 5 via the first bearing 8; in this embodiment, the first bearings 8 are arranged in pairs and are tapered roller bearings, and the paired first bearings 8 are arranged back to back along the axial direction of the tube shaft 1, so that the axial compensation capacity of the first bearings 8 is improved; and the tube shaft pole shoe assembly 6 forms a magnetic liquid sealing structure between the tube shaft 1 and the sealing seat 5, and similarly, the magnetic liquid sealing structure is a prior art and is not described here;

[0036] In addition, an elastic retaining ring is fixed to the lower end of the inner ring of the first bearing 8 close to the tubular shaft pole shoe assembly 6, and a tubular shaft bearing gasket 7 is arranged at the lower end of the outer ring, and one end of the tubular shaft bearing gasket 7 extends toward the tubular shaft pole shoe assembly 6, thereby achieving the axial limiting capability of the tubular shaft pole shoe assembly 6 at the same time, a stop gasket 12 is arranged at the upper end of the inner ring of the first bearing 8 away from the tubular shaft pole shoe assembly 6, and a sealing seat cover plate 16 is arranged at the upper end of the outer ring, a pipe nut 13 is arranged between the sealing seat cover plate 16 and the sealing seat 5, the pipe nut 13 is screwed to the tubular shaft 1 and presses the stop gasket 12 to the inner ring of the first bearing 8, thereby achieving the purpose of axial limiting the first bearing 8.

[0037] Example 2

[0038] In order to further improve the sealing ability and reliability of the structure, this embodiment 2 further provides a magnetic liquid sealing structure for the rotation of the inner and outer shafts based on the technical solution of embodiment 1, such as Figure 1-Figure 2 As shown, a plurality of second O-rings 11 are arranged between the inner shaft and the high-speed shaft sleeve 14 , and the plurality of second O-rings 11 are distributed along the axial direction of the high-speed shaft sleeve 14 to prevent external impurities from entering through the gap between the inner shaft and the high-speed shaft sleeve.

[0039] In this embodiment, a second skeleton oil seal 10 and a liquid collection tray 9 are sequentially arranged below the high-speed shaft pole shoe assembly. An annular groove is arranged in the middle of the liquid collection tray 9. The opening of the annular groove faces the second skeleton oil seal 10. The leaked magnetic liquid is collected through the annular groove to prevent the magnetic liquid from losing pressure and falling into the equipment.

[0040] In this embodiment, in order to prevent the bearing lubricating oil from falling into the tubular shaft pole shoe assembly 6, a first skeleton oil seal 2 is provided between the tubular shaft pole shoe assembly 6 and the first bearing 8. The first skeleton oil seal 2 is embedded in the inner wall surface of the tubular shaft bearing gasket 7.

[0041] To prevent dust from entering the sealing structure, a first skeleton oil seal 2 is respectively arranged between the upper and lower ends of the sealing seat 5 and the tube shaft 1. The first skeleton oil seal 2 is embedded in the inner wall surface of the sealing seat cover plate 16, and the first skeleton oil seal 2 located below the tube shaft pole shoe assembly 6 is connected to the sealing seat 5 through the shaft seal pressure plate 3, which can also prevent some particles or liquids from entering the pole shoe.

[0042] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the utility model in detail. It should be understood that the above description is only the specific implementation method of the utility model and is not used to limit the protection scope of the utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A magnetic liquid sealing structure for inner and outer shaft rotation, characterized in that: It comprises an inner shaft and a hollow outer shaft, wherein the inner shaft is inserted into the hollow part of the outer shaft, and the outer shaft is inserted into the sealing seat; Wherein, a first magnetic liquid sealing component is arranged between the hollow wall surface of the inner shaft and the outer shaft, and the inner shaft rotates relative to the outer shaft through the first magnetic liquid sealing component; A second magnetic liquid sealing component is arranged between the outer shaft and the sealing seat, and the outer shaft rotates relative to the sealing seat through the second magnetic liquid sealing component.

2. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 1, characterized in that: The first magnetic liquid sealing component comprises a high-speed shaft sleeve (14), a high-speed shaft pole shoe component (15) and a second bearing (19); the inner shaft passes through the high-speed shaft sleeve (14) and is inserted into the hollow portion of the outer shaft; the high-speed shaft pole shoe component (15) and the second bearing (19) are sequentially arranged on the outer periphery of the high-speed shaft sleeve (14) along the axial direction of the inner shaft; The high-speed shaft pole shoe assembly (15) forms a magnetic liquid sealing structure between the shaft sleeve and the hollow wall surface of the outer shaft, and the inner shaft is connected to the outer shaft via the second bearing (19).

3. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 2, characterized in that: The first magnetic liquid sealing assembly further comprises a bearing washer (17), a shaft elastic retaining ring (18) and a hole elastic retaining ring (20); The shaft elastic retaining ring (18) is arranged at the upper and lower ends of the inner ring of the second bearing (19), the hole elastic retaining ring (20) and the bearing washer (17) are respectively arranged at the upper and lower ends of the outer ring of the second bearing (19), and the bearing washer (17) extends toward the high-speed shaft pole shoe assembly (15).

4. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 2, characterized in that: A plurality of second O-type sealing rings (11) are arranged between the inner shaft and the high-speed shaft sleeve (14), and the plurality of second O-type sealing rings (11) are distributed along the axial direction of the high-speed shaft sleeve (14).

5. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 2, characterized in that: A second skeleton oil seal (10) is arranged below the high-speed shaft pole shoe assembly (15).

6. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 5, characterized in that: A liquid collection tray (9) is arranged below the second skeleton oil seal (10), and an annular groove is arranged in the middle of the liquid collection tray (9), with the opening of the annular groove facing the second skeleton oil seal (10).

7. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 1, characterized in that: The second magnetic liquid sealing component comprises a tube shaft pole shoe component (6) and a first bearing (8), wherein the tube shaft pole shoe component (6) and the first bearing (8) are sequentially arranged between the outer shaft and the sealing seat along the axial direction of the outer shaft; The outer shaft is connected to the sealing seat via the first bearing (8), the first bearings (8) are arranged in pairs and are tapered roller bearings, and the first bearings (8) arranged in pairs are arranged back to back along the axial direction of the outer shaft; The tube shaft pole shoe assembly (6) forms a magnetic liquid sealing structure between the outer shaft and the sealing seat.

8. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 7, characterized in that: A first skeleton oil seal (2) is provided between the tubular shaft pole shoe assembly (6) and the first bearing (8).

9. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 7, characterized in that: A first skeleton oil seal (2) is respectively arranged between the upper and lower ends of the sealing seat and the outer shaft.

10. A magnetic liquid sealing structure for inner and outer shaft rotation according to claim 7, characterized in that: The second magnetic liquid sealing assembly also includes an elastic retaining ring, a stop washer (12) and a pipe nut (13); The elastic retaining ring is used to fix the inner ring of the first bearing (8) at the lower end, the retaining washer (12) is arranged at the inner ring of the first bearing (8) at the upper end, and the pipe nut (13) is screwed with the outer shaft thread and presses the retaining washer (12) against the inner ring of the first bearing (8).

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