阅读说明：本技术 一种有效减少润滑油向腔体泄漏的罗茨泵密封结构 (Effectively reduce lobe pump seal structure of lubricating oil to cavity leakage ) 是由 李正清 李小金 刘筱文 蔡宇宏 马凤英 何丹 韩仙虎 马敏 李晓霞 王毅 于 2020-12-14 设计创作，主要内容包括：本发明涉及罗茨泵密封技术领域,公开了一种有效减少润滑油向腔体泄漏的罗茨泵密封结构,安装在罗茨泵的转子轴上；所述转子轴上设置有腔体端盖,还套装有轴承和压紧轴套；包括卡套、涨圈、静密封件和密封圈压套；所述腔体端盖和转子轴的两者之间设置有卡套,卡套与腔体端盖之间设置有涨圈；所述腔体端盖与轴承相对的端面上设置有静密封件,所述静密封件和转子轴之间设置有密封圈压套；所述密封圈压套还位于腔体端盖和轴承之间,所述静密封件与密封圈压套之间设置有封严蓖齿结构。本发明通过静密封和动密封相结合的方式,有效减少油污等气体向工作腔体空间的泄漏,大大提高了密封结构的密封性能,其整体结构简单、可靠也易于实现。(The invention relates to the technical field of Roots pump sealing, and discloses a Roots pump sealing structure for effectively reducing the leakage of lubricating oil to a cavity, which is arranged on a rotor shaft of a Roots pump; the rotor shaft is provided with a cavity end cover, and is also sleeved with a bearing and a pressing shaft sleeve; comprises a cutting sleeve, an expansion ring, a static sealing element and a sealing ring pressing sleeve; a clamping sleeve is arranged between the cavity end cover and the rotor shaft, and an expansion ring is arranged between the clamping sleeve and the cavity end cover; a static sealing element is arranged on the end face of the cavity end cover opposite to the bearing, and a sealing ring pressing sleeve is arranged between the static sealing element and the rotor shaft; the sealing ring pressing sleeve is also positioned between the cavity end cover and the bearing, and a sealing labyrinth structure is arranged between the static sealing element and the sealing ring pressing sleeve. The invention effectively reduces the leakage of oil stain and other gases to the space of the working cavity by combining the static seal and the dynamic seal, greatly improves the sealing performance of the sealing structure, and has simple and reliable integral structure and easy realization.)

1. A sealing structure of a Roots pump for effectively reducing the leakage of lubricating oil to a cavity is arranged on a rotor shaft of the Roots pump; the rotor shaft is provided with a cavity end cover, and is also sleeved with a bearing and a pressing shaft sleeve; the method is characterized in that: the sealing structure comprises a clamping sleeve, an expansion ring, a static sealing element and a sealing ring pressing sleeve;

a clamping sleeve is arranged between the cavity end cover and the rotor shaft, and an expansion ring is arranged between the clamping sleeve and the cavity end cover; a static sealing element is arranged on the end face of the cavity end cover opposite to the bearing, and a sealing ring pressing sleeve is arranged between the static sealing element and the rotor shaft; the sealing ring pressing sleeve is also positioned between the cavity end cover and the bearing, and a sealing labyrinth structure is arranged between the static sealing element and the sealing ring pressing sleeve.

2. The roots pump seal structure effective in reducing leakage of lubricant to a cavity of claim 1, wherein: and the static sealing element and the cavity end cover are fixedly connected through a compression bolt.

3. The roots pump seal structure effective in reducing leakage of lubricant to the cavity of claim 2, wherein: and a static sealing ring is arranged between the static sealing element and the cavity end cover and close to the compression bolt.

4. The roots pump seal structure effective in reducing leakage of lubricant to the cavity of claim 2, wherein: and a movable sealing ring is arranged between the sealing ring pressing sleeve and the cavity end cover and close to the clamping sleeve.

5. The roots pump seal structure effective in reducing leakage of lubricant to the cavity of claim 2, wherein: the seal ring pressing sleeve comprises a main part and a side part, the main part is sleeved on the rotor shaft, and a movable seal ring is arranged between the main part and the cavity end cover and close to the clamping sleeve; the side part is positioned on the static sealing element, and a sealing labyrinth structure is formed between the side part and the static sealing element.

6. The roots pump seal structure effective in reducing leakage of lubricant to the cavity of claim 5, wherein: the main portion is located between the static seal and the rotor shaft and also between the cavity end cap and the bearing; the side portion extends outwardly from a middle of the main portion and is located on the static seal.

7. The roots pump seal structure effective in reducing leakage of lubricant to a cavity of claim 1, wherein: and an adjusting washer is arranged between the bearing and the compressing shaft sleeve.

8. The roots pump seal structure effective in reducing leakage of lubricant to a cavity of claim 7, wherein: and a wave spring is also arranged between the bearing and the pressing shaft sleeve and is positioned between the adjusting washer and the pressing shaft sleeve.

9. The roots pump seal structure effective in reducing leakage of lubricant to a cavity of claim 1, wherein: the sealed labyrinth structure between the static sealing element and the sealing ring pressing sleeve adopts an asymmetric structure.

10. The roots pump seal structure effective in reducing leakage of lubricant to the cavity of claim 2, wherein: the compression bolt is positioned on one side, far away from the rotor shaft, of the sealing labyrinth structure.

Technical Field

The invention relates to the technical field of sealing of roots pumps, in particular to a sealing structure of a roots pump, which can effectively reduce the leakage of lubricating oil to a cavity.

Background

The roots pump is a vacuum pump without internal compression, the compression ratio is usually very low, and the ultimate vacuum of the roots pump mainly depends on the sealing structure of the roots pump besides the structure and the manufacturing precision of the roots pump. With the increasing application of roots pumps, the roots pumps are widely applied to the metallurgy, petrochemical industry, paper making, food, electronic industry and other departments. The sealing structure of the prior Roots pump mainly adopts a piston ring sealing structure, so that most of oil-gas transmission is reduced, but the sealing structure can not meet the design requirements of industries with higher pollution requirements on food, electronics and the like, and needs to be improved and designed, so that the leakage of lubricating oil steam to a pump body cavity is further reduced, and the product pumping quality index can meet the requirements of the food and electronics industries and the like.

Disclosure of Invention

The invention aims to solve the technical problems in the prior art, and provides a sealing structure of a roots pump for effectively reducing the leakage of lubricating oil to a cavity, which can solve the problem of the leakage of lubricating oil steam to a working cavity in the working process of the roots pump, effectively reduce the leakage amount of oil gas and improve the sealing performance.

In order to solve the problems proposed above, the technical scheme adopted by the invention is as follows:

the invention provides a sealing structure of a roots pump for effectively reducing the leakage of lubricating oil to a cavity, which is arranged on a rotor shaft of the roots pump; the rotor shaft is provided with a cavity end cover, and is also sleeved with a bearing and a pressing shaft sleeve; the sealing structure comprises a clamping sleeve, an expansion ring, a static sealing element and a sealing ring pressing sleeve;

a clamping sleeve is arranged between the cavity end cover and the rotor shaft, and an expansion ring is arranged between the clamping sleeve and the rotor shaft; a static sealing element is arranged on the end face of the cavity end cover opposite to the bearing, and a sealing ring pressing sleeve is arranged between the static sealing element and the rotor shaft; the sealing ring pressing sleeve is also positioned between the rotor and the bearing, and a sealing labyrinth structure is arranged between the static sealing element and the sealing ring pressing sleeve.

Furthermore, the static sealing element and the cavity end cover are fixedly connected through a compression bolt.

Further, a static sealing ring is arranged between the static sealing element and the cavity end cover and close to the compression bolt.

Furthermore, a dynamic seal ring is arranged between the seal ring pressing sleeve and the cavity end cover and close to the clamping sleeve.

Furthermore, the seal ring pressing sleeve comprises a main part and a side part, the main part is sleeved on the driving rotor shaft and the driven rotor shaft, and a movable seal ring is arranged between the main part and the cavity end cover and close to the clamping sleeve; the side part is positioned on the static sealing element, and a sealing labyrinth structure is formed between the side part and the static sealing element.

Further, the main portion is located between the static seal and the rotor shaft, and also between the cavity end cover and the bearing; the side portion extends outwardly from a middle of the main portion and is located on the static seal.

Further, an adjusting washer is arranged between the bearing and the pressing shaft sleeve.

Further, a wave spring is arranged between the bearing and the pressing shaft sleeve and is positioned between the adjusting washer and the pressing shaft sleeve.

Furthermore, a sealed labyrinth structure between the static sealing element and the sealing ring pressing sleeve adopts an asymmetric structure.

Further, the compression bolt is located on the side, away from the rotor shaft, of the sealing labyrinth structure.

Compared with the prior art, the invention has the beneficial effects that:

the sealing structure of the roots pump provided by the invention is used for solving the problem of large oil return amount in the working process of the roots pump, and the static sealing and dynamic sealing are combined by the static sealing piece and the sealing ring pressing sleeve, so that the leakage of oil stain and other gases to the space of the working cavity is effectively reduced, namely, the oil return amount in the normal working of the roots pump is effectively reduced, the sealing performance of the sealing structure is greatly improved, the working reliability of the roots pump is ensured, and the sealing structure is simple, reliable and easy to realize.

Drawings

In order to illustrate the solution of the invention more clearly, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are some embodiments of the invention, and that other drawings may be derived from these drawings by a person skilled in the art without inventive effort. Wherein:

fig. 1 is a front view of a sealing structure of a roots pump for effectively reducing the leakage of lubricating oil to a cavity according to the present invention.

Fig. 2 is a left side view of the sealing structure of the roots pump for effectively reducing the leakage of the lubricating oil to the cavity.

The reference numerals are explained below: 1-cavity end cover, 2-rotor shaft, 3-cutting sleeve, 4-piston ring, 5-static sealing element, 6-hold-down bolt, 7-sealing ring pressing sleeve, 71-main part, 72-side part, 8-static sealing ring, 9-dynamic sealing ring, 10-bearing, 11-hold-down shaft sleeve, 12-adjusting washer and 13-wave spring.

Detailed Description

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs; the terminology used in the description presented herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention, e.g., the terms "length," "width," "upper," "lower," "left," "right," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," "outer," etc., refer to an orientation or position based on that shown in the drawings, are for convenience of description only and are not to be construed as limiting of the present disclosure.

The terms "including" and "having," and any variations thereof, in the description and claims of this invention and the description of the above figures are intended to cover non-exclusive inclusions; the terms "first," "second," and the like in the description and in the claims, or in the drawings, are used for distinguishing between different objects and not necessarily for describing a particular sequential order. In the description and claims of the present invention and in the description of the above figures, when an element is referred to as being "fixed" or "mounted" or "disposed" or "connected" to another element, it may be directly or indirectly located on the other element. For example, when an element is referred to as being "connected to" another element, it can be directly or indirectly connected to the other element.

Furthermore, reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

Referring to fig. 1, the sealing structure of the roots pump for effectively reducing the leakage of the lubricating oil to the cavity is provided, and is installed on a rotor shaft 2 of the roots pump, a cavity end cover 1 is installed on the rotor shaft 2, and a bearing 10 and a pressing shaft sleeve 11 are further sleeved on the rotor shaft 2.

The sealing structure comprises a clamping sleeve 3, an expansion ring 4, a static sealing element 5 and a sealing ring pressing sleeve 7, the clamping sleeve 3 is arranged between the cavity end cover 1 and the rotor shaft 2, and the expansion ring 4 is arranged between the clamping sleeve 3 and the cavity end cover 1. And a static sealing element 5 is arranged on the end surface of the cavity end cover 1 opposite to the bearing 10, and a sealing ring pressing sleeve 7 is arranged between the static sealing element 5 and the rotor shaft 2. The sealing ring pressing sleeve 7 is also positioned between the cavity end cover 1 and the bearing 10. And a sealing labyrinth structure is arranged between the static sealing element 5 and the sealing ring pressing sleeve 7.

In the embodiment of the invention, one side of the cavity end cover 1 is a rotor cavity, and the other side of the cavity end cover is a lubricating oil cavity. The seal ring pressing sleeve 7 and the cutting sleeve 3 realize dynamic seal, and the static seal part 5 realizes static seal. In actual work, rotor shaft 2 can be for initiative or driven, and the dynamic seal part rotates along with rotor shaft 2, and under the effect of centrifugal force, oil steam or oil that its contact will be got rid of on the outer end cover, and outer end cover and external direct contact simultaneously, the temperature is lower, will make the oil gas liquefaction of getting rid of to converge to in the lubricating oil.

In the embodiment of the invention, the number of the piston rings 4 between the cutting sleeve 3 and the cavity end cover 1 can be increased or decreased according to actual needs. And a labyrinth tooth sealing structure is arranged between the static sealing element 5 and the sealing ring pressing sleeve 7, so that the sealing capability of the sealing structure is further improved.

Further, the static sealing element 5 and the cavity end cover 1 are fixedly connected through a compression bolt 6, so that the connection reliability between the static sealing element and the cavity end cover is ensured. In particular, in order to ensure the stability of the installation, the number of the compression bolts 6 can also be adjusted according to actual needs, and the compression bolts are located on the side of the sealing labyrinth structure away from the driving rotor shaft 2 and the driven rotor shaft 2, that is, the sealing labyrinth structure is located between the rotor shaft 2 and the compression bolts 6.

Further, a static sealing ring 8 is arranged between the static sealing element 5 and the cavity end cover 1 and close to the compression bolt 6; and a dynamic seal ring 9 is arranged between the seal ring pressing sleeve 7 and the rotor shaft 2 and close to the cutting sleeve 3.

In the embodiment of the invention, by arranging the static seal ring 8 and the dynamic seal ring 9, oil gas leakage from a lubricating oil cavity to a rotor cavity needs to pass through a gap between the rotor shaft 2 and the cavity end cover 1, and meanwhile, as the clamping sleeve 3 and the piston ring 4 are arranged between the rotor shaft 2 and the cavity end cover 1, the relationship among the parts is as follows: cavity end cover 1 contacts with cutting ferrule 3 and 4 subassemblies of piston ring, and cutting ferrule 3 and 4 subassemblies of piston ring contact with rotor shaft 2, consequently has two clearances, is first clearance respectively: a gap is formed between the cavity end cover 1 and the clamping sleeve 3 and piston ring 4 assembly; a second gap: the clearance between the clamping sleeve 3 and the piston ring 4 assembly and the rotor shaft 2.

Furthermore, because the static sealing ring 8 is positioned between the cavity end cover 1 and the static sealing element 5, the oil gas in the lubricating oil cavity is effectively blocked from flowing to the first gap, and meanwhile, a sealing labyrinth structure is designed between the static sealing element 5 and the sealing ring pressing sleeve 7, so that the gas in the lubricating oil cavity is effectively blocked from flowing to the first gap, and the effective sealing of the first gap is realized. And the dynamic seal ring 9 is located between the cutting ferrule 3, the rotor shaft 2 and the seal ring pressing sleeve 7, under the action of the pressing shaft sleeve 11 and the wave spring 13, the adjusting gasket 12 is deformed, the second gap between the cutting ferrule 3 and the shaft is effectively sealed, the leakage of oil gas in the lubricating oil cavity to the rotor cavity through the second gap is blocked, and the second gap is effectively sealed. Therefore, through the effective sealing of the first gap and the second gap, the leakage of oil gas in the lubricating oil cavity to the rotor cavity is blocked, and the sealing performance of the sealing structure is further improved.

Further, the seal ring pressing sleeve 7 comprises a main portion 71 and a side portion 72, the main portion 71 is sleeved on the rotor shaft 2, and a dynamic seal ring 9 is arranged between the main portion 71 and the cavity end cover 1. The side part 72 is positioned on the static sealing element 5, and a sealing labyrinth structure is formed between the side part and the static sealing element 5.

In particular, the main portion 71 is located between the static seal 5 and the rotor shaft 2, and also between the cavity end cover 1 and the bearing 10; the side portion 72 extends outward from the middle of the main portion 71 and is located on the static seal 5.

Furthermore, the sealing labyrinth structure between the static sealing element 5 and the sealing ring pressing sleeve 7 adopts an asymmetric structure, a concave-convex toothed structure is arranged on the end face of the static sealing element 5 matched with the sealing ring pressing sleeve 7 to form the sealing labyrinth structure, and the choke flow effect is increased by arranging the sealing labyrinth structure.

Further, an adjusting washer 12 for adjusting is arranged between the bearing 10 and the pressing sleeve 11.

Further, a wave spring 13 is arranged between the bearing 10 and the pressing shaft sleeve 11 and is positioned between the adjusting washer 12 and the pressing shaft sleeve 11, so that the compactness and the stability of the whole structure are ensured. Specifically, one end of the wave spring 13 is located at the outer edge of the pressing shaft sleeve 11, and the other end is connected to the end face of the adjusting washer 12 opposite to the pressing shaft sleeve 11. Through setting up adjusting washer 12 and wave spring 13 have guaranteed static sealing member 5, sealing washer pressure cover 7 can closely laminate with cavity end cover 1, rotor shaft 2 to overall structure's leakproofness has also been guaranteed.

In the embodiment of the invention, the dynamic seal part throws out the contacted oil gas to the wall surface of the lubricating oil cavity in the process of rotating along with the rotor shaft 2, and the oil gas is cooled to be liquid on the wall surface and converged into the lubricating oil at the bottom. Meanwhile, the dynamic sealing part drives the airflow nearby to rotate in the rotating process, the airflow flows to the wall surface of the lubricating oil cavity under the action of centrifugal force, and the air on the wall surface flows to the lubricating oil cavity. If oil drops exist on the static sealing part, the oil drops flow along the wall surface of the static sealing part to axial pores, flow onto the sealing grate of the dynamic seal at the sealing grate structure under the action of air flow and gravity, and are thrown out to the wall surface of the cavity through the passive seal.

The sealing structure of the roots pump provided by the embodiment of the invention is additionally provided with a dynamic and static combined sealing structure on the basis of not changing the original sealing structure, the dynamic sealing part fully utilizes the centrifugal force generated during the operation of the dynamic sealing part, and under the action of the centrifugal force, oil gas is prevented from moving to the working cavity, so that the oil gas moves to the wall surface of the lubricating oil cavity, the leakage of oil stain and other gases to the cavity space is effectively reduced, the sealing performance of the sealing structure is improved, the air extraction quality of the roots pump is also improved, and the roots pump can be applied to the industries of food, electronics and the like.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.