CN-224228861-U - Roots pump self-adaptation sealing device and Roots pump

CN224228861UCN 224228861 UCN224228861 UCN 224228861UCN-224228861-U

Abstract

The utility model provides a self-adaptive sealing device of a Roots pump and the Roots pump, the device is sleeved between a rotating shaft and a shell of the Roots pump, the device is used for sealing between the rotating shaft and the shell of the Roots pump and comprises two fixed baffles in an annular structure and a flexible sealing structure. The two fixing baffles penetrate through the rotating shaft and are oppositely arranged in the axial direction of the rotating shaft, the flexible sealing structure is clamped between the two fixing baffles and is provided with a plurality of flexible gaps penetrating through the thickness of the flexible sealing structure, so that a plurality of cantilevers are formed at one end of the flexible sealing structure, which faces the rotating shaft, and a preset gap is formed between the end part of each cantilever and the rotating shaft. The flexible seal structure in the device can follow the deformation of pivot and take place self-adaptation deformation when the pivot takes place to warp, seals between lobe pump pivot and the casing, reduces the pivot clearance and reveal the volume, improves the effective pumping speed of lobe pump, prolongs the life of pivot, and the device is not fragile owing to its good self-adaptation, can prolong the whole life of vacuum pump.

Inventors

LEI XIAOBO
FENG WEI
PAN JIE
Han Pengdong
Ning Tianze

Assignees

北京通嘉宏瑞科技有限公司

Dates

Publication Date: 20260512
Application Date: 20250516

Claims (10)

1. The utility model provides a roots pump self-adaptation device of sealing tightly, overlaps is located between roots pump's pivot and the casing for seal between roots pump's pivot and the casing, its characterized in that, the device includes: The two fixed baffles are of annular structures, penetrate through the rotating shaft and are oppositely arranged in the axial direction of the rotating shaft; The flexible sealing structure is clamped between the two fixed baffles and is provided with a plurality of flexible gaps penetrating through the thickness of the flexible sealing structure, so that a plurality of cantilevers are formed at one end of the flexible sealing structure, which faces the rotating shaft, and a preset gap is formed between the end part of each cantilever and the rotating shaft.
2. The apparatus of claim 1, wherein the end of each cantilever has a thrust curve parallel to the outer wall curve of the shaft.
3. The apparatus of claim 2, wherein the flexible sealing structure comprises a low pressure sealing layer and at least one high pressure sealing layer disposed overlying the low pressure sealing layer, wherein, The width of the thrust curved surface in the high-pressure sealing layer is consistent with the thickness of the cantilever.
4. A device according to claim 3, wherein the cantilever in the low pressure seal layer is extended by a predetermined length along the axis of rotation toward the side facing away from the high pressure seal layer, such that a predetermined length of mating gap is formed between the thrust curved surface in the low pressure seal layer and the axis of rotation.
5. The apparatus of claim 4 wherein the distance from the thrust curve in the high pressure seal layer to the shaft outer wall curve is greater than the distance from the thrust curve in the low pressure seal layer to the shaft wall surface.
6. A device according to claim 3, wherein the cantilevers of the high pressure sealing layer are distributed in the circumferential direction of the rotation axis in the flexible gap between two adjacent cantilevers in the low pressure sealing layer.
7. The apparatus according to any one of claims 3 to 6, wherein the number of the high-pressure sealing layers is plural, and the plural high-pressure sealing layers are stacked in order along the axial direction of the rotation shaft, The flexible gaps of two adjacent high-pressure sealing layers are distributed in a staggered manner.
8. A device according to any one of claims 1 to 3, wherein a plurality of the flexible gaps extend from the end of the cantilever in a radially outward direction of the flexible seal structure in a positive radial direction and then extend obliquely in a direction opposite to the rotation direction of the rotating shaft.
9. The device of any one of claims 1 to 3, further comprising a gasket interposed between the fixed barrier and the flexible sealing structure, wherein, The gap between the circumferential inner wall of the gasket and the outer wall of the rotating shaft is larger than the preset gap between the end part of the cantilever and the rotating shaft.
10. A roots pump comprising the roots pump adaptive seal of any one of claims 1 to 9.

Description

Roots pump self-adaptation sealing device and Roots pump Technical Field The utility model belongs to the technical field of vacuum pumps, and particularly relates to a self-adaptive sealing device of a Roots pump and the Roots pump. Background The rotor of the Roots vacuum pump has parallel axes, and is formed by combining impellers and shafts, and small gaps are arranged between the impellers, between the impellers and the casing and between the impellers and the bearing plates so as to avoid mutual contact. Gap leakage, particularly when leakage occurs between the rotating shaft and the shell of the multi-stage rotor Roots pump, has great influence on the performance of the Roots vacuum pump. With the continuous development and perfection of the Roots pump technology, the problem of dynamic sealing of the rotating shaft of the high-performance Roots pump gradually becomes a bottleneck problem for restricting the performance of the Roots pump. At present, the rotors of each level of the multistage Roots pump are sealed by using sealing rings between a rotating shaft and a shell, and the sealing rings are easy to wear due to micro deformation generated when the rotating shaft rotates at high speed, so that the interstage leakage generated after the sealing rings are worn has huge influence on the performance of the Roots pump. To solve the above problems, it is necessary to provide a Roots pump self-adaptive sealing device and a Roots pump which are reasonable in design and effectively solve the above problems. Disclosure of utility model The utility model aims to at least solve one of the technical problems in the prior art and provides a self-adaptive sealing device of a Roots pump and the Roots pump. One aspect of the present utility model provides a self-adaptive sealing device for a Roots pump, which is sleeved between a rotating shaft of the Roots pump and a housing, and is used for sealing between the rotating shaft of the Roots pump and the housing, and the self-adaptive sealing device comprises: The two fixed baffles are of annular structures, penetrate through the rotating shaft and are oppositely arranged in the axial direction of the rotating shaft; The flexible sealing structure is clamped between the two fixed baffles and is provided with a plurality of flexible gaps penetrating through the thickness of the flexible sealing structure, so that a plurality of cantilevers are formed at one end of the flexible sealing structure, which faces the rotating shaft, and a preset gap is formed between the end part of each cantilever and the rotating shaft. Optionally, the end of each cantilever has a thrust curved surface parallel to the curved surface of the outer wall of the rotating shaft. Optionally, the flexible sealing structure comprises a low-pressure sealing layer and at least one high-pressure sealing layer overlapped with the low-pressure sealing layer, wherein, The width of the thrust curved surface in the high-pressure sealing layer is consistent with the thickness of the cantilever. Optionally, the cantilever in the low-pressure sealing layer extends a preset length along the axial direction of the rotating shaft towards one side away from the high-pressure sealing layer, so that a fit clearance with a preset length is formed between the thrust curved surface in the low-pressure sealing layer and the rotating shaft. Optionally, the distance from the thrust curved surface in the high-pressure sealing layer to the curved surface of the outer wall of the rotating shaft is greater than the distance from the thrust curved surface in the low-pressure sealing layer to the wall surface of the rotating shaft. Optionally, the cantilevers of the high-pressure sealing layer are distributed in the flexible gap between two adjacent cantilevers in the low-pressure sealing layer along the circumferential direction of the rotating shaft. Optionally, the number of the high-pressure sealing layers is multiple, the multiple high-pressure sealing layers are sequentially overlapped along the axial direction of the rotating shaft, wherein, The flexible gaps of two adjacent high-pressure sealing layers are distributed in a staggered manner. Optionally, the plurality of flexible gaps extend from the end of the cantilever to the radial outer side of the flexible sealing structure in a positive radial direction and then extend obliquely, and the oblique direction is opposite to the rotation direction of the rotating shaft. Optionally, the device further comprises a gasket, the gasket is clamped between the fixed baffle and the flexible sealing structure, wherein, The gap between the circumferential inner wall of the gasket and the outer wall of the rotating shaft is larger than the preset gap between the end part of the cantilever and the rotating shaft. Another aspect of the present utility model provides a Roots pump comprising the foregoing Roots pump self-adaptive seal device. The self-adaptive sealing device of