Clearance-adjustment-free sealing structure and screw compressor using same
By adopting a maze sealing structure and a knurled sealing structure in the screw compressor, the sealing between the screw rotor and the main bearing seat is easily failed and difficult to assemble, achieving a good sealing effect and simplifying the assembly process.
Patent Information
- Application Number
- CN202422123329.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-30
- Publication Date
- 2025-06-20
- Estimated Expiration
- 2034-08-30
AI Technical Summary
The seal between the screw rotor and the main bearing seat in a screw compressor is prone to failure, making the assembly difficult and time long.
The labyrinth sealing structure and the knurled sealing structure are adopted. The labyrinth sealing structure is passed through a multi-channel concave-convex nesting structure. The knurled sealing structure sets a knurled area on the screw rotor to jointly achieve the separation of the high-pressure area and the low-pressure area.
The good sealing effect between the screw rotor and the main bearing seat is achieved, and the damage to the contact seal and the leakage of non-contact seals are avoided. At the same time, the axial gap is free tolerant, the gap adjustment steps are eliminated, and the assembly process is simplified.
Smart Images
Figure CN223004155U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of the sealing structure of a screw compressor, in particular to a sealing structure with no need of adjusting clearance and a screw compressor using the same. Background Art
[0002] When a screw compressor is in operation, sealing is required between parts with different pressures, and the sealing of moving and rotating parts is an important issue. In a screw compressor, a main bearing is installed in the inner cavity of a main bearing seat, and the inner cavity of the main bearing seat is communicated with a low-pressure area through a pressure balance hole, so that the inner cavity of the main bearing seat is also a low-pressure area. As the screw rotor rotates, the exhaust screw groove in the exhaust port area starts to discharge high-pressure gas to the exhaust port. The high-pressure areas of the exhaust screw groove and the exhaust port are adjacent to the inner cavity of the main bearing seat. Here, a sealing structure is required to seal between the screw rotor, which is a moving and rotating part, and the main bearing seat, so as to separate the high-pressure area and the low-pressure area.
[0003] The clearance between the screw rotor and the main bearing seat is a key dimension and needs to be adjusted using an adjusting shim. This is acceptable for screw rotors with not very large sizes, but for large screw rotors and main shafts, due to size and weight problems, it is time-consuming and laborious to adjust.
[0004] In view of this, how to solve the problems existing in the sealing between the screw rotor and the main bearing seat in the existing screw compressor, such as easy failure, large assembly difficulty, and long assembly time, becomes the topic to be studied in the present utility model. Content of the Utility Model
[0005] The purpose of the present utility model is to provide a sealing structure with no need of adjusting clearance and a screw compressor using the same.
[0006] To achieve the above object, in the first aspect, a technical solution adopted by the present utility model is: to provide a sealing structure with no need of adjusting clearance for the rotary sealing of a screw compressor. The screw compressor has a rotor cavity housing, and a main shaft, a screw rotor, and a main bearing seat are installed in the rotor cavity housing. The innovation lies in:
[0007] The sealing structure includes a labyrinth sealing structure provided between the screw rotor and the main bearing seat and a knurling sealing structure provided on the screw rotor.
[0008] The labyrinth sealing structure includes a recess and a protrusion provided on the screw rotor at the docking part with the main bearing seat, and a protrusion and a recess provided on the main bearing seat at the docking part with the screw rotor.
[0009] The knurling sealing structure includes at least a knurling area provided on the area of the screw rotor close to the docking part with the main bearing seat.
[0010] To achieve the above-mentioned purpose, in a second aspect, a technical solution adopted by the present invention is: to provide a screw compressor, wherein the screw compressor uses the sealing structure without adjusting the gap described in the first aspect of the present invention.
[0011] The relevant contents of this utility model are explained as follows:
[0012] 1. In the utility model, through the study of sealing between the screw rotor as a moving rotating part and the main bearing seat in the screw compressor to separate the high-pressure area and the low-pressure area, a labyrinth seal structure and a knurled seal structure are used to jointly realize the separation of the high-pressure area and the low-pressure area. The use of this structure overcomes the problem that the contact seal is easily damaged and the sealing effect of the non-contact seal is not ideal. While ensuring a good sealing effect, the labyrinth seal structure between the screw rotor and the main bearing seat makes the axial clearance between the screw rotor and the main bearing seat a free tolerance, so that there is no need to adjust the clearance between the screw rotor and the main bearing seat during the assembly process, especially making the assembly process of the four-star wheel (dual rotor) single screw compressor simpler.
[0013] 2. In the solution of the first aspect above, the labyrinth sealing structure is a multi-channel concave-convex nested structure, so as to make the sealing effect of the labyrinth sealing structure better and reduce and avoid leakage.
[0014] 3. In the scheme of the first aspect above, a first protrusion and two first recessed portions are provided on the screw rotor at the portion where it connects with the main bearing seat, and a second recessed portion and two second protrusions are provided on the main bearing seat at the portion where it connects with the screw rotor, the first protrusion is nested with the second recessed portion, and the second protrusion is nested with the first recessed portion, so as to form a multi-channel concave-convex nested labyrinth sealing structure to further improve the sealing effect.
[0015] 4. In the scheme of the first aspect above, the first protrusion is annular, and a plurality of annular grooves are provided on the circumferential outer side and inner side of the first protrusion. The plurality of annular grooves cooperate with the inner and outer side walls of the second recessed portion to form a plurality of concave and convex nesting between the first protrusion and the second recessed portion, thereby improving the sealing effect.
[0016] 5. In the solution of the first aspect above, the second protrusion is further provided with two protrusions on the axial outer surface, and the first recess is correspondingly provided with two recesses, forming a multi-channel concave-convex nesting between the second protrusion and the first recess, so as to improve the sealing effect.
[0017] 6. In the solution of the first aspect above, the screw rotor includes a rotor main body and a plurality of exhaust screw grooves provided on the circumferential side of the rotor main body. There is an outer cylindrical surface extending from one end to the other end of the rotor main body between adjacent screw grooves. The knurled area is arranged in a section of the outer cylindrical surface close to the main bearing seat, and the knurled area has an axial length h, and the axial length h satisfies at least being greater than or equal to the distance from the high-pressure area in the rotor cavity housing to the inner end of the rotor main body, so as to ensure that an adequate auxiliary sealing effect is achieved at the knurled area, thereby further enhancing the sealing effect.
[0018] 7. In the solution of the second aspect above, the screw rotors are symmetrically arranged on both axial sides of the main bearing seat, and the sealing structures are arranged between the two screw rotors and the main bearing seat, thereby constituting a four-star wheel (double-rotor) single-screw compressor.
[0019] 8. In the present utility model, unless otherwise clearly specified and defined, terms such as "installation", "connection", "connection", "fixation" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium. It can be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0020] 9. In the present utility model, the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "axial", "bottom", "inner", "outer", etc. is the orientation or positional assembly relationship based on the orientation or position shown in the drawings. It is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.
[0021] 10. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0022] Due to the application of the above solutions, the present utility model has the following advantages and effects compared with the prior art:
[0023] In the technical solution of the present utility model, through the research on the sealing between the screw rotor, which is a moving and rotating component in the screw compressor, and the main bearing seat to separate the high-pressure area and the low-pressure area, a labyrinth seal structure and a knurled seal structure are used to jointly achieve the separation of the high-pressure area and the low-pressure area. While ensuring a good sealing effect, the labyrinth seal structure between the screw rotor and the main bearing seat makes the axial clearance between the screw rotor and the main bearing seat a free tolerance, so that there is no need to adjust the clearance between the screw rotor and the main bearing seat during the assembly process. In particular, it can make the assembly process of the four-star wheel (double-rotor) single-screw compressor simpler. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 is a schematic diagram of an embodiment of the present utility model;
[0025] Figure 2 is Figure 1 an enlarged schematic view of part I in
[0026] Figure 3 is a schematic diagram when the screw rotor and the main bearing seat are assembled in an embodiment of the present utility model;
[0027] Figure 4 is a three-dimensional schematic diagram of the screw rotor in an embodiment of the present utility model;
[0028] Figure 5 is Figure 4 an enlarged schematic view of part II in
[0029] The parts in the above drawings are represented as follows:
[0030] 1 Rotor cavity housing
[0031] 2 Main shaft
[0032] 3 Screw rotor
[0033] 31 Exhaust screw groove
[0034] 32 Outer cylindrical surface
[0035] 33 Pressure balance hole
[0036] 4 Main bearing seat
[0037] 41 Inner cavity of the main bearing seat
[0038] 42 Main bearing
[0039] 5 Labyrinth seal structure
[0040] 51 First protrusion
[0041] 511 Annular groove
[0042] 52 First recess
[0043] 53 Second recess
[0044] 54 Second protrusion
[0045] 6 Knurled seal structure
[0046] 61 Knurled area
[0047] 91 Low-pressure area
[0048] 92 High-pressure area. Detailed implementation manners
[0049] To make the above objects, features, and advantages of the present application more obvious and understandable, the following will describe the detailed implementation manners of the present application in conjunction with the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.
[0050] Embodiment 1, as shown in the attached Figure 1 to the attached Figure 5 As shown, the embodiment of the present utility model discloses a seal structure with no need to adjust the clearance for the rotary seal of a screw compressor. The screw compressor has a rotor cavity housing 1, and a main shaft 2, a screw rotor 3, and a main bearing seat 4 are installed in the rotor cavity housing 1.
[0051] The seal structure includes a labyrinth seal structure 5 provided between the screw rotor 3 and the main bearing seat 4, and a knurled seal structure 6 provided on the screw rotor 3.
[0052] The labyrinth seal structure 5 includes a recess and a protrusion at the docking part of the screw rotor 3 and the main bearing seat 4, and a protrusion and a recess at the docking part of the main bearing seat 4 and the screw rotor 3.
[0053] The knurled seal structure 6 includes at least a knurled area 61 provided on the area of the screw rotor 3 close to the docking part of the main bearing seat 4.
[0054] Through the implementation of Embodiment 1 of the present utility model, through the research on sealing between the screw rotor 3, which is a moving and rotating component in the screw compressor, and the main bearing seat 4 to separate the high-pressure area 92 and the low-pressure area 91, the labyrinth seal structure 5 and the knurled seal structure 6 are used to jointly achieve the separation of the high-pressure area 92 and the low-pressure area 91. By adopting this structure, the problems that the contact seal is easily damaged and the sealing effect of the non-contact seal is not ideal are overcome. While ensuring a good sealing effect, the labyrinth seal structure 5 between the screw rotor 3 and the main bearing seat 4 makes the axial clearance between the screw rotor 3 and the main bearing seat 4 a free tolerance, so that there is no need to adjust the clearance between the screw rotor 3 and the main bearing seat 4 during the assembly process. In particular, it can make the assembly process of the four-star wheel (double-rotor) single-screw compressor simpler.
[0055] In Embodiment 1 of the present utility model, the labyrinth seal structure 5 is a multi-channel concave-convex nested structure, so as to make the sealing effect of the labyrinth seal structure 5 better and reduce or avoid leakage.
[0056] In Embodiment 1 of the present utility model, the first protrusion 51 is annular, and a plurality of annular grooves 511 are opened on the outer and inner circumferences of the first protrusion 51. The cooperation between the plurality of annular grooves 511 and the inner and outer side walls of the second recess 53 forms a multi-channel concave-convex nesting between the first protrusion 51 and the second recess 53, so as to improve the sealing effect.
[0057] In Embodiment 1 of the present utility model, two protrusions are further provided on the axially outer surface of the second protrusion 54, and two corresponding depressions are provided on the first recess 52, forming a multi-channel concave-convex nesting between the second protrusion 54 and the first recess, so as to improve the sealing effect.
[0058] In addition, in a specific implementation manner of Embodiment 1 of the present utility model, the screw rotor 3 includes a rotor main body and a plurality of exhaust screw grooves 31 provided on the circumference of the rotor main body. There is an outer cylindrical surface 32 extending from one end to the other end of the rotor main body between adjacent screw grooves. The knurled area 61 is arranged in a section of the outer cylindrical surface 32 close to the main bearing seat 4, and the knurled area 61 has an axial length h, and the axial length h satisfies at least being greater than or equal to the distance from the high-pressure area 92 in the rotor cavity housing 1 to the inner end of the rotor main body, so as to ensure that the knurled area 61 plays an adequate auxiliary sealing role, thereby further improving the sealing effect.
[0059] Embodiment 2, Embodiment 2 of the present utility model proposes a screw compressor, and the compressor uses the seal structure with non-adjustable clearance as described in Embodiment 1 of the present utility model.
[0060] In the second embodiment of the present utility model, the screw rotors 3 are symmetrically arranged on both axial sides of the main bearing seat 4, and the sealing structures are arranged between the two screw rotors 3 and the main bearing seat 4, thus forming a four-star wheel (double-rotor) single-screw compressor.
[0061] Next, the solution of the present utility model will be described with a specific detailed embodiment.
[0062] In this detailed embodiment, the main shaft 2 of the screw compressor is installed in the inner cavity 41 of the main bearing seat. The screw rotors 3 are symmetrically arranged on both axial sides of the main bearing seat 4. The inner cavity 41 of the main bearing seat is communicated with the low-pressure area 91 through the pressure balance hole 33, so that the inner cavity 41 of the main bearing seat is also the low-pressure area 91. As the screw rotor 3 rotates, the exhaust screw groove 31 in the exhaust port area starts to discharge high-pressure gas to the exhaust port. The high-pressure areas 92 of the exhaust screw groove 31 and the exhaust port are adjacent to the inner cavity 41 of the main bearing seat. Here, a sealing structure composed of a labyrinth sealing structure 5 and a knurled sealing structure 6 is used to seal between the screw rotor 3 as a moving and rotating part and the main bearing seat 4.
[0063] In this detailed embodiment, the labyrinth sealing structure 5 is a multi-channel concave-convex nested structure. The labyrinth sealing structure 5 includes depressions and protrusions provided on the screw rotor 3 at the docking part with the main bearing seat 4, and protrusions and depressions provided on the main bearing seat 4 at the docking part with the screw rotor 3. A first protrusion 51 and two first depressions 52 are provided on the screw rotor 3 at the docking part with the main bearing seat 4. A second depression 53 and two second protrusions 54 are provided on the main bearing seat 4 at the docking part with the screw rotor 3. The first protrusion 51 is nested and matched with the second depression 53, and the second protrusion 54 is nested and matched with the first depression 52, thus forming a multi-channel concave-convex nested labyrinth sealing structure 5 with this structure.
[0064] For the formation of the multi-channel concave-convex nested labyrinth sealing structure 5, the following can be referred to:
[0065] The first protrusion 51 is annular, and a plurality of annular grooves 511 are opened on the outer and inner circumferences of the first protrusion 51. The cooperation of the plurality of annular grooves 511 with the inner and outer side walls of the second depression 53 forms a multi-channel concave-convex nesting between the first protrusion 51 and the second depression 53. Two protrusions are also provided on the axially outer surface of the second protrusion 54, and two depressions are correspondingly provided on the first depression 52, forming a multi-channel concave-convex nesting between the second protrusion 54 and the first depression.
[0066] In this specific embodiment, the knurled sealing structure 6 includes at least a knurled area 61 provided on the screw rotor 3 in an area close to the docking part of the main bearing seat 4. The screw rotor 3 includes a rotor main body and a plurality of exhaust screw grooves 31 provided on the circumferential side of the rotor main body. There is an outer cylindrical surface 32 extending from one end to the other end of the rotor main body between adjacent screw grooves. The knurled area 61 is arranged in an area of the outer cylindrical surface 32 close to the main bearing seat 4.
[0067] The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.
Claims
1. A sealing structure without adjusting the gap, used for the rotary seal of a screw compressor, wherein the screw compressor comprises a rotor chamber housing (1), wherein a main shaft (2), a screw rotor (3), and a main bearing seat (4) are installed in the rotor chamber housing (1); the characteristics are: The sealing structure comprises a labyrinth sealing structure (5) provided between the screw rotor (3) and the main bearing seat (4), and a knurled sealing structure (6) provided on the screw rotor (3); The labyrinth seal structure (5) comprises a depression and a protrusion provided at a portion of the screw rotor (3) that is connected to the main bearing seat (4), and a protrusion and a depression provided at a portion of the main bearing seat (4) that is connected to the screw rotor (3); The knurled seal structure (6) comprises a knurled area (61) at least provided on an area of the screw rotor (3) close to abutment with the main bearing seat (4).
2. A sealing structure without gap adjustment according to claim 1, characterized in that: The labyrinth sealing structure (5) is a multi-channel concave-convex nested structure.
3. A sealing structure without gap adjustment according to claim 2, characterized in that: A first protrusion (51) and two first recesses (52) are provided on the screw rotor (3) at a position connected to the main bearing seat (4); a second recess (53) and two second protrusions (54) are provided on the main bearing seat (4) at a position connected to the screw rotor (3); the first protrusion (51) is nested with the second recess (53), and the second protrusion (54) is nested with the first recess (52).
4. The sealing structure without gap adjustment according to claim 3, characterized in that: The first protrusion (51) is annular in shape, and a plurality of annular grooves (511) are provided on the circumferential outer side and inner side of the first protrusion (51).
5. The sealing structure without gap adjustment according to claim 3, characterized in that: The second protrusion (54) is further provided with two protrusions on its axially outer surface, and the first recessed portion (52) is correspondingly provided with two recesses.
6. The sealing structure without gap adjustment according to claim 1, characterized in that: The screw rotor (3) comprises a rotor body and a plurality of exhaust screw grooves (31) arranged on the circumferential side of the rotor body, and an outer cylindrical surface (32) extending from one end of the rotor body to the other end is provided between adjacent screw grooves, and the knurled area (61) is arranged on a section of the outer cylindrical surface (32) close to the main bearing seat (4), and the knurled area (61) has an axial length h.
7. A screw compressor, characterized in that: The compressor uses the gap-free sealing structure according to any one of claims 1 to 6.
8. The screw compressor according to claim 7, characterized in that: The screw rotors (3) are symmetrically arranged on both axial sides of the main bearing seat (4), and the sealing structure is arranged between the two screw rotors (3) and the main bearing seat (4).