Shaft end sealing structure and screw compressor

Abstract

The utility model discloses a shaft end sealing structure and a screw compressor, and relates to the technical field of screw compressors, in particular to a shaft end sealing structure which comprises a retainer, a shaft end sealing ring and a shaft end sealing ring, the sealing lip piece is of an annular structure made of an elastic material, the sealing lip piece and the retainer are coaxially and fixedly arranged, and the inner diameter of the sealing lip piece is smaller than the outer diameter of the sealing face on the periphery of the shaft end part; according to the shaft end sealing structure and the screw compressor, the elastic sealing lip piece is arranged in the shaft hole, and the inner diameter of the sealing lip piece is smaller than the diameter of the peripheral sealing face of the shaft end, so that the inner ring position of the assembled sealing lip piece is extruded to bend and deform towards one end, and the end face of one end of the sealing lip piece is in contact sealing with the peripheral sealing face of the shaft end; and the elastic deformation of the sealing lip is utilized to automatically compensate the change of the gap between the shaft and the shaft hole, so that the sealing performance between the shaft and the shaft hole after long-term operation of equipment is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of screw compressors, and more specifically, to a shaft end sealing structure. In addition, the utility model also relates to a screw compressor comprising the shaft end sealing structure. Background Art

[0002] The screw compressors currently on the market use bearings to support the screw and the shaft hole of the seat body, and there is a clearance fit between the shaft end of the screw and the shaft hole. As the screw rotates for a long time, the clearance between the shaft hole and the shaft end of the screw will increase, causing air or oil leakage, resulting in increased vibration of the screw during equipment operation, which in turn causes displacement, heat and wear of the bearing, further exacerbating air and oil leakage, seriously affecting the compression efficiency of the compressor and reducing the overall performance of the compressor.

[0003] In summary, how to provide a solution to the problem of decreased sealing between the screw shaft end and the shaft hole after the compressor is used for a long time is an urgent problem to be solved by those skilled in the art. Utility Model Content

[0004] In view of this, the purpose of the utility model is to provide a shaft end sealing structure, by arranging an elastic sealing lip in the shaft hole, and the inner diameter of the sealing lip is smaller than the diameter of the outer peripheral sealing surface of the shaft end. Therefore, the inner ring position of the assembled sealing lip will be squeezed and bent toward one end, so that the end face of one end of the sealing lip contacts and seals with the outer peripheral sealing surface of the shaft end, and the elastic deformation of the sealing lip itself is utilized to automatically compensate for the change of the gap between the shaft and the shaft hole, thereby ensuring the sealing performance between the two after the equipment is operated for a long time.

[0005] Another object of the utility model is to provide a screw compressor including the above-mentioned shaft end sealing structure, which has the same technical solution and can solve the same technical problem.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A shaft end sealing structure is arranged between the outer periphery of the shaft end and the inner wall of the shaft hole of the seat body, comprising:

[0008] The retainer is an annular structure and is coaxially arranged with the axial hole of the seat body;

[0009] The sealing lip is an annular structure made of elastic material and is coaxially fixed with the retaining frame, and the inner diameter of the sealing lip is smaller than the outer diameter of the outer peripheral sealing surface of the shaft end;

[0010] When the sealing lip is coaxially assembled with the outer peripheral sealing surface of the shaft end, the inner ring position of the sealing lip is bent toward one end along its own center line direction, and the other end surface contacts and seals with the outer peripheral sealing surface of the shaft end.

[0011] Preferably, an inner ring surface of the retaining frame is provided with an assembly groove, the sealing lip is fixedly arranged in the assembly groove, and a support frame for fixing the sealing lip is arranged in the assembly groove.

[0012] Preferably, the groove width of the assembly groove is not greater than the sum of the thicknesses of the support frame and the sealing lip, and the groove walls on both sides of the assembly groove have different heights;

[0013] One end surface of the sealing lip abuts against the high groove wall, and the other end surface abuts against one end surface of the support frame, and the other end surface of the support frame abuts against the low groove wall.

[0014] Preferably, a guiding slope is provided at a position of the groove wall with a high height close to the opening of the assembly groove, and the included angle between the guiding slope and the groove wall is an obtuse angle;

[0015] The sealing lip is in contact with the guide slope.

[0016] Preferably, it further comprises an inner retaining spring, wherein the inner retaining spring is fixedly installed relative to the axial hole of the seat body;

[0017] The end surfaces of both ends of the retaining frame are respectively in contact with the inner hole shoulder of the shaft hole and the end surface of the inner retaining spring.

[0018] Preferably, an outer peripheral surface of the retaining frame and an inner wall of the shaft hole are in interference fit.

[0019] Preferably, it further comprises a sealing sleeve, wherein the sealing sleeve is coaxially arranged with the end of the shaft, and the two ends of the sealing sleeve are respectively in contact with the shaft shoulder of the shaft and the inner ring of the bearing arranged outside the shaft;

[0020] The outer diameter of the sealing sleeve is greater than the inner diameter of the sealing lip.

[0021] Preferably, the radial thickness of the sealing sleeve is not greater than the shoulder height of the shaft, and the outer diameter of the sealing sleeve is smaller than the inner diameter of the outer ring of the bearing.

[0022] A screw compressor comprises a screw, wherein a shaft end sealing structure as described above is arranged between an end of the screw and the shaft hole.

[0023] Preferably, the outer end of the shaft hole is connected to an end cover by bolts, and an O-shaped sealing ring is provided between the end cover and the edge position of the outer end of the shaft hole.

[0024] Compared with the prior art, the shaft end sealing structure provided by the utility model has at least the following beneficial effects:

[0025] A sealing lip is provided between the shaft and the shaft hole. Since the inner diameter of the sealing lip is smaller than the outer diameter of the sealing surface on the outer periphery of the shaft end, when the sealing lip contacts the sealing surface on the outer periphery of the shaft end, the elastic deformation of the sealing lip causes one end face of the sealing lip to always contact and seal with the sealing surface on the outer periphery of the shaft end, thereby ensuring the sealing between the shaft and the shaft hole. The elastic deformation of the sealing lip can automatically compensate for the change in the gap between the shaft end and the shaft hole, effectively avoiding air leakage or oil leakage, and extending the overall service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0027] Figure 1 It is a cross-sectional schematic diagram of a specific screw compressor provided by the utility model;

[0028] Figure 2 Provided by the utility model Figure 1 Enlarged view of point A in the middle;

[0029] Figure 3 Provided by the utility model Figure 1 Enlarged view of point B in the middle;

[0030] Figure 4 Provided by the utility model Figure 2 Enlarged view of center C.

[0031] Figure 1-Figure 4 middle:

[0032] 1. Shaft; 2. Seat body; 3. Support frame; 4. Cage; 41. Assembly groove; 42. Guide slope; 5. Sealing lip; 6. Sealing sleeve; 7. Internal retaining ring; 8. End cover; 9. Sealing ring. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] The core of the utility model is to provide a shaft end sealing structure, by arranging an elastic sealing lip in the shaft hole, and the inner diameter of the sealing lip is smaller than the diameter of the outer peripheral sealing surface of the shaft end, therefore, the inner ring position of the assembled sealing lip will be squeezed and bent toward one end, thereby making the end face of one end of the sealing lip contact and seal with the outer peripheral sealing surface of the shaft end, and utilizing the elastic deformation of the sealing lip itself to automatically compensate for the change in the gap between the shaft and the shaft hole, thereby ensuring the sealing performance between the two after long-term operation of the equipment.

[0035] Another core of the utility model is to provide a screw compressor including the above-mentioned shaft end sealing structure, which has the same technical solution and can solve the same technical problem.

[0036] Please refer to Figure 2-Figure 4 , a shaft end sealing structure, arranged between the outer periphery of the end of the shaft 1 and the inner wall of the shaft hole of the seat body 2, comprising:

[0037] The retainer 4 is an annular structure and is coaxially arranged with the axial hole of the seat body 2;

[0038] The sealing lip 5 is an annular structure made of elastic material and is coaxially fixed with the retaining frame 4. The inner diameter of the sealing lip 5 is smaller than the outer diameter of the outer peripheral sealing surface of the end of the shaft 1.

[0039] When the sealing lip 5 is coaxially assembled with the peripheral sealing surface at the end of the shaft 1, the inner ring position of the sealing lip 5 is bent toward one end along its own center line direction, and the other end surface contacts and seals with the peripheral sealing surface at the end of the shaft 1.

[0040] The seat body 2 can be specifically a box body or a base, such as Figure 2 and Figure 4 As shown, there is a clearance fit between the end of the shaft 1 and the shaft hole of the seat body 2, and there are problems of air leakage and oil leakage. By arranging an annular retainer 4 in the shaft hole, an annular sealing lip 5 is arranged between the outer peripheral sealing surface of the end of the shaft 1 and the inner wall of the shaft hole. Since the inner diameter of the sealing lip 5 is smaller than the outer diameter of the outer peripheral sealing surface of the end of the shaft 1, the inner ring position of the sealing lip 5 is squeezed and bends and deforms toward one end along its own center line direction, while the end face of the other end abuts against the outer peripheral sealing surface of the end of the shaft 1, thereby forming a sealing contact, which effectively improves the sealing performance between the shaft hole and the end of the shaft 1.

[0041] At the same time, when shaft 1 vibrates during operation, the gap between the outer peripheral sealing surface at the end of shaft 1 and the inner wall of the shaft hole will change dynamically. At this time, since the sealing lip 5 is made of elastic material, it can undergo elastic deformation and automatically compensate for the change in the gap between the outer peripheral sealing surface at the end of shaft 1 and the inner wall of the shaft hole caused by the vibration of shaft 1, thereby improving the sealing between the end of shaft 1 and the shaft hole during operation and effectively avoiding problems such as air leakage and oil leakage.

[0042] In some embodiments, the inner annular surface of the retaining frame 4 is provided with a mounting groove 41 , the sealing lip 5 is fixedly disposed in the mounting groove 41 , and a support frame 3 for fixing the sealing lip 5 is disposed in the mounting groove 41 .

[0043] like Figure 4 As shown, both the retaining frame 4 and the sealing lip 5 are annular structures, and in the actual working process, there is relative rotation between the sealing lip 5 and the shaft 1; an assembly groove 41 is provided in the retaining frame 4, and the sealing lip 5 is fixedly mounted in the retaining frame 4 by arranging a support frame 3 in the assembly groove 41, wherein the support frame 3 is also annular structure, and is coaxially fixedly mounted with the retaining frame 4 and the sealing lip 5.

[0044] In some embodiments, the sealing lip 5 and the retaining frame 4 adopt an integrated structural design, and the two are connected by pressing, ultrasonic welding, etc., which can also achieve the above functions.

[0045] In some embodiments, the width of the assembly groove 41 is not greater than the sum of the thicknesses of the support frame 3 and the sealing lip 5, and the groove walls on both sides of the assembly groove 41 have different heights;

[0046] One end surface of the sealing lip 5 abuts against a high groove wall, and the other end surface abuts against one end surface of the support frame 3 , while the other end surface of the support frame 3 abuts against a low groove wall.

[0047] like Figure 4 As shown, the support frame 3 and the sealing lip 5 are assembled in the assembly groove 41 at the same time, and the sum of the thickness of the support frame 3 and the sealing lip 5 is greater than or equal to the width of the assembly groove 41. Therefore, after assembly, the support frame 3 and the groove wall of the assembly groove 41 can squeeze the sealing lip 5 from both sides, so that there is a large friction force between the end face of the sealing lip 5 and the groove wall and the end face of the support frame 3, so that the sealing lip 5 can be firmly fixed.

[0048] In some embodiments, a guide slope 42 is provided at a position of the groove wall with a high height close to the opening of the assembly groove 41, and the included angle between the guide slope 42 and the groove wall is an obtuse angle;

[0049] The sealing lip 5 abuts against the guide slope 42 .

[0050] like Figure 4 As shown, a guiding slope 42 is provided on the groove wall on the higher side. When the support frame 3 and the sealing lip 5 are installed into the assembly groove 41, the sealing lip 5 automatically abuts against the groove wall and the guiding slope 42 at the corresponding position, so that the sealing lip 5 is automatically bent toward one end in the direction of its own center line, and the angle α between the bent portion and the original portion is an obtuse angle, preferably 120°, 135°, 145°, etc. It is worth noting that the minimum inner diameter of the bent portion is still smaller than the outer diameter of the sealing surface at the end of the shaft 1, and the inner ring portion of the bent portion exceeds the assembly groove 41 and contacts and seals with the sealing surface at the end of the shaft 1.

[0051] In some embodiments, Figure 4 As shown, the sealing lip 5 is bent toward the other end. In actual use, the bending direction and bending angle of the sealing lip 5 should be selected according to the actual pressure of the cavity to be sealed and the structure of the sealing position.

[0052] In some embodiments, an inner retaining spring 7 is further included, and the inner retaining spring 7 is fixedly installed relative to the axial hole of the seat body 2;

[0053] The end surfaces of both ends of the retainer 4 abut against the inner shoulder of the shaft hole and the end surface of the inner retaining spring 7 respectively.

[0054] like Figure 2 and Figure 4 As shown, a hole shoulder is provided in the shaft hole so that one end of the retaining frame 4 abuts against the hole shoulder, and an internal retaining spring 7 is provided in the shaft hole so as to abut against the other end of the retaining frame 4, thereby limiting the abutment of both ends of the retaining frame 4 and preventing the retaining frame 4 from being displaced in the axial direction.

[0055] In some embodiments, an outer peripheral surface of the retainer 4 and an inner wall of the shaft hole are in interference fit.

[0056] like Figure 4 As shown, when the retaining frame 4 is assembled, it is mainly positioned by the hole shoulder and the internal retaining spring 7, and an interference fit is adopted between the retaining frame 4 itself and the inner wall of the shaft hole, so that the retaining frame 4 and the inner side of the shaft hole of the seat body 2 can maintain a long-lasting and tight sealing state, avoiding the risk of high-pressure leakage caused by the gap caused by the transition fit, thereby further improving the sealing performance.

[0057] In some embodiments, it further comprises a sealing sleeve 6, which is coaxially arranged with the end of the shaft 1, and the two ends of the sealing sleeve 6 are respectively in contact with the shaft shoulder of the shaft 1 and the inner ring of the bearing arranged outside the shaft 1;

[0058] The outer diameter of the sealing sleeve 6 is larger than the inner diameter of the sealing lip 5 .

[0059] like Figure 4 As shown, by providing a sealing sleeve 6, and the two ends of the sealing sleeve 6 are respectively in contact with the shoulder of the shaft 1 and the inner ring of the bearing, the sealing of the two end portions of the sealing sleeve 6 is achieved, and the sealing lip 5 is in contact and sealed with the outer peripheral surface of the sealing sleeve 6, so that the outer peripheral surface of the sealing sleeve 6 serves as the outer peripheral sealing surface of the shaft end. During operation, the sealing sleeve 6 rotates with the shaft 1, and the sealing sleeve 6 and the sealing lip 5 are in contact and sealed with each other, and there is relative movement, and both have the advantage of being easy to disassemble and replace, thereby improving the overall maintenance convenience of the equipment.

[0060] In some embodiments, the radial thickness of the sealing sleeve 6 is not greater than the shoulder height of the shaft 1 , and the outer diameter of the sealing sleeve 6 is smaller than the inner diameter of the outer ring of the bearing.

[0061] like Figure 4 As shown, the thickness of the sealing sleeve 6 is not greater than the height of the shaft shoulder of the shaft 1, that is, the outer diameter of the sealing sleeve 6 is not greater than the outer diameter of the shaft 1, thereby making it easy to assemble the sealing sleeve 6 into the shaft hole;

[0062] The outer diameter of the sealing sleeve 6 is smaller than the inner diameter of the outer ring of the bearing, that is, after the sealing sleeve 6 abuts against the inner ring of the bearing, it will not abut against the outer ring of the bearing, thereby avoiding the influence of the sealing sleeve 6 on the rotation of the bearing.

[0063] In addition to the shaft end sealing structures disclosed in the above embodiments, the utility model also provides a screw compressor including the above shaft end sealing structure, the screw compressor includes a screw, and any of the above shaft end sealing structures is arranged between the end of the screw and the shaft hole.

[0064] In some embodiments, the outer end of the shaft hole is connected to an end cover 8 by bolts, and an O-shaped sealing ring 9 is provided between the end cover 8 and the edge of the outer end of the shaft hole.

[0065] like Figure 1 and Figure 3 As shown, an end cover 8 is arranged at the end of the shaft hole, and a sealing ring 9 is arranged between the end cover 8 and the edge of the shaft hole to further enhance the sealing performance of the end of the shaft hole.

[0066] In some embodiments, the sealing ring 9 is disposed between the end surface of the bearing outer ring and the end cover 8, which can also achieve the above-mentioned function.

[0067] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0068] The shaft end sealing structure and the screw compressor provided by the utility model are introduced in detail above. The principle and implementation method of the utility model are explained in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the utility model. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the utility model, the utility model can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the utility model.

Claims

1. A shaft end sealing structure, used to be arranged between the outer periphery of the end of a shaft (1) and the inner wall of the shaft hole of a seat body (2), characterized in that: include: The retaining frame (4) is an annular structure and is coaxially arranged with the axial hole of the seat body (2); The sealing lip (5) is an annular structure made of elastic material and is coaxially fixedly arranged with the retaining frame (4); the inner diameter of the sealing lip (5) is smaller than the outer diameter of the outer peripheral sealing surface of the end of the shaft (1); When the sealing lip (5) is coaxially assembled with the outer peripheral sealing surface of the end of the shaft (1), the inner ring position of the sealing lip (5) is bent toward one end along its own centerline direction, and the other end surface contacts and seals with the outer peripheral sealing surface of the end of the shaft (1).

2. The shaft end sealing structure according to claim 1, characterized in that: The inner annular surface of the retaining frame (4) is provided with an assembly groove (41), the sealing lip (5) is fixedly arranged in the assembly groove (41), and a support frame (3) for fixing the sealing lip (5) is arranged in the assembly groove (41).

3. The shaft end sealing structure according to claim 2, characterized in that: The width of the assembly groove (41) is no greater than the sum of the thicknesses of the support frame (3) and the sealing lip (5), and the groove walls on both sides of the assembly groove (41) have different heights; One end surface of the sealing lip (5) abuts against the groove wall of a higher height, and the other end surface abuts against one end surface of the support frame (3), and the other end surface of the support frame (3) abuts against the groove wall of a lower height.

4. The shaft end sealing structure according to claim 3, characterized in that: A guide slope (42) is provided at a position of the groove wall with a high height close to the opening of the assembly groove (41), and the included angle between the guide slope (42) and the groove wall is an obtuse angle; The sealing lip (5) abuts against the guiding inclined surface (42).

5. The shaft end sealing structure according to claim 1, characterized in that: It also includes an inner retaining spring (7), the inner retaining spring (7) being fixedly mounted relative to the axial hole of the seat body (2); The end surfaces of both ends of the retaining frame (4) are respectively in contact with the inner hole shoulder of the shaft hole and the end surface of the inner retaining spring (7).

6. The shaft end sealing structure according to claim 5, characterized in that: An interference fit is formed between the outer peripheral surface of the retaining frame (4) and the inner wall of the shaft hole.

7. The shaft end sealing structure according to any one of claims 1 to 6, characterized in that: It also comprises a sealing sleeve (6), the sealing sleeve (6) being coaxially arranged with the end of the shaft (1), and the two ends of the sealing sleeve (6) respectively abutting against the shaft shoulder of the shaft (1) and the inner ring of a bearing arranged outside the shaft (1); The outer diameter of the sealing sleeve (6) is greater than the inner diameter of the sealing lip (5).

8. The shaft end sealing structure according to claim 7, characterized in that: The radial thickness of the sealing sleeve (6) is not greater than the height of the shaft shoulder of the shaft (1), and the outer diameter of the sealing sleeve (6) is smaller than the inner diameter of the outer ring of the bearing.

9. A screw compressor, characterized in that: It comprises a screw rod, and an axial end sealing structure according to any one of claims 1 to 8 is arranged between the end of the screw rod and the axial hole.

10. The screw compressor according to claim 9, characterized in that: The outer end of the shaft hole is connected to an end cover (8) via bolts, and an O-shaped sealing ring (9) is provided between the end cover (8) and the edge of the outer end of the shaft hole.

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