CN211039678U - Axial self-sealing shaft seal device and compressor - Google Patents

Abstract

The utility model provides an axial self-sealing shaft seal device, comprising a main shaft, a shaft seal and a bearing seat sleeved on the main shaft, a back pressure cavity is formed between the shaft seal, the bearing seat and the main shaft; the shaft seal It includes an accommodating cavity and a shell cylinder, and the inner wall of the accommodating cavity is provided with a plurality of annular grooves; a cavity is provided between the shaft seal and the main shaft, and the cavity consists of a small annular cavity and a large annular cavity Alternate structure; the outer wall and bottom of the shell cylinder form an abutment surface with the bearing seat, when the back pressure chamber is under pressure, the pressure acts on the shaft seal, and then is transmitted to the abutment surface to form the shaft seal and the bearing seat Contact seal between. The utility model also provides a compressor with an axial self-sealing shaft sealing device. The utility model has the advantages of simple structure, good sealing effect, zero leakage and small loss of shaft power, realizes the axial self-sealing without contact between the shaft seal and the main shaft, and is suitable for various liquid shaft seal devices.

Description

Axial self-sealing shaft sealing device and compressor

technical field

The utility model relates to the field of compressors, in particular to an axial self-sealing shaft sealing device.

Background technique

In the design of electric scroll compressors, considering the axial adjustment of the gap between the movable scroll and the stationary scroll, it is often necessary to design a back pressure surface on the back of the movable scroll, which requires a formation between the movable scroll and the bearing seat. A sealed cavity; because the bearing seat and the main shaft are relatively rotating, it is necessary to use a shaft seal for sealing; and the standard shaft seals on the market are generally well-fitted with the main shaft, resulting in a large loss of shaft power. The general improvement method is to increase the shaft power by improving the self-lubrication of the material, but this increases the production cost of standard shaft seals.

Utility model content

In view of the defects in the prior art, the purpose of the present invention is to provide an axial self-sealing shaft seal device. The shaft seal device in the present invention has a simple structure, good sealing effect, zero leakage, and small shaft power loss, and realizes the Axial self-sealing with no contact between the shaft seal and the main shaft, suitable for various liquid shaft seal devices.

According to one aspect of the present invention, an axial self-sealing shaft seal device is provided, comprising a main shaft (1), a shaft seal (2) and a bearing seat (3) sleeved on the main shaft (1), the bearing The seat (3) jackets the shaft seal (2) on the main shaft (1), and the end face of the inner cavity of the bearing seat (3) is flush with the upper end face of the shaft seal (2), the shaft seal (2) A back pressure cavity (4) is formed between the bearing seat (3) and the main shaft (1); the shaft seal (2) includes an accommodating cavity (21) and a casing cylinder (22). A plurality of annular grooves (23) are arranged on the inner wall; a cavity is arranged between the shaft seal (2) and the main shaft (1), and the cavity consists of a small annular cavity (5) and a large annular cavity ( 6) Alternately constituted, the large annular cavity (6) is composed of an annular groove (23) and the outer wall of the main shaft (1), and the small annular cavity (5) is composed of the accommodating cavity (21) except the annular groove ( 23) The outer inner wall is formed with the outer wall of the main shaft (1); the outer wall and bottom of the outer shell cylinder (22) and the bearing seat (3) form an abutment surface (7), and the back pressure chamber (4) is under pressure When the pressure is applied to the shaft seal (2), it is then transmitted to the abutment surface (7) to form a contact seal between the shaft seal (2) and the bearing seat (3).

Preferably, the shaft seal (2) is of a large upper and lower small structure, and the abutment surface (7) formed by the outer wall of the casing cylinder (22) and the bearing seat (3) is from top to bottom to the main shaft (1) Side tilt setting. The shaft seal (2) is arranged in a large upper and lower small structure to form a pressure angle, so that the pressure sealing performance formed by the shaft seal and the bearing seat is better.

Preferably, the upper end surface of the shaft seal (2) is further provided with a groove (24), and the groove (24) is formed between the outer wall of the accommodating cavity (21) and the inner wall of the outer casing (22). 24), the open end of the groove (24) faces the back pressure cavity (4). When the shaft seal is under pressure, the groove is deformed to the inner wall of the accommodating cavity and the outer wall of the outer casing, so that the shaft seal fits better with the bearing seat and the main shaft, and the sealing performance is strengthened; at the same time, the shaft seal is assembled during the assembly process. The inner side wall of the middle accommodating cavity will be deformed by the extrusion of the external force. The groove between the outer wall of the accommodating cavity and the inner wall of the outer casing can buffer the deformation of the side wall of the accommodating cavity to a great extent, thus effectively preventing the shaft seal from being assembled. The side wall is damaged due to extrusion deformation during the process.

Preferably, at least two annular grooves (23) are provided. The number of annular grooves is determined according to the height of the bearing seat. The more annular grooves are arranged, the stronger the sealing effect between the shaft seal and the main shaft will be, and the goal of zero leakage of refrigeration oil can be achieved.

Preferably, the width of the large annular cavity (6) is greater than the width of the small annular cavity (5). The width of the large annular cavity and the small annular cavity is related to the structure and material of the shaft seal, the pressure on the shaft seal, and the flow rate. Generally, the smaller the width of the small annular cavity, the larger the width of the large annular cavity, the better.

Preferably, the width of the large annular cavity (6) is 10 times the width of the small annular cavity (5).

Preferably, the annular groove (23) is any one of a concave triangular groove, an arc-shaped groove, a square groove, a rectangular groove, a trapezoidal groove or a polygonal groove. When the concave depths are different, the maximum depth of the annular groove when it is concave plus the width of the small annular cavity is the maximum width of the large annular cavity, and the width of the large annular cavity is 10 times the width of the small annular cavity. times, means that the maximum width of the large annular cavity is 10 times the width of the small annular cavity.

Preferably, the main shaft (1) is in clearance fit with the shaft seal (2), and the main shaft (1) is in clearance fit with the bearing seat (3).

Preferably, the shaft seal (2) is made of polytetrafluoroethylene or polyether ether ketone material. It is elastic, deformed under pressure, and will stick to the bearing seat to form a good sealing effect.

Preferably, an accommodating groove for accommodating the shaft seal (2) is provided on the upper part of the accommodating cavity of the bearing seat (3) sleeved on the main shaft (1), and the accommodating groove cooperates with the outer wall and the bottom of the casing cylinder (22) to seal .

The second purpose of the utility model is to provide a compressor with good sealing performance in order to overcome the deficiencies of the prior art. In order to achieve the above purpose, the present invention is achieved through the following technical solutions: a shaft sealing device including the aforementioned axial self-sealing is provided on the back pressure surface of the movable scroll of the compressor.

Preferably, the main shaft (1) is in clearance fit with the shaft seal (2), and the main shaft (1) is in clearance fit with the bearing seat (3).

The working principle is: the refrigeration oil in the back pressure cavity leaks into the cavity between the shaft seal and the main shaft under the action of the pressure P; after the refrigeration oil is throttled through the small inlet of the small annular cavity, it enters the large annular cavity In the middle, the fluid forms a strong vortex in the large annular cavity, which reduces the pressure from the initial pressure P to P1, and the refrigeration oil passes through the next small annular cavity and the large annular cavity. Descending from P1 to P2, the leakage rate of refrigeration oil almost disappears completely, thus achieving the sealing effect.

Compared with the prior art, the utility model has the following beneficial effects:

(1) The axial self-sealing shaft seal device involved in the present utility model has good sealing effect, zero leakage and small shaft power loss, realizes the axial self-sealing without contact between the shaft seal and the main shaft, and is suitable for various liquid shafts. sealed device;

(2) The axial self-sealing shaft seal device involved in the present utility model, the shaft seal is arranged in a structure with a large upper and a small lower, forming a pressure angle, so that the pressure sealing performance formed by the shaft seal and the bearing seat is better;

(3) In the axial self-sealing shaft seal device of the present invention, grooves are arranged on the shaft seal, so that the sealing effect between the shaft seal, the bearing seat and the main shaft is stronger, and the shaft seal accommodates the cavity during the assembly process. The inner side wall will be deformed by the extrusion of the external force. The groove between the outer wall of the accommodating cavity and the inner wall of the outer casing can buffer the deformation of the side wall of the accommodating cavity to a great extent, thus effectively preventing the shaft seal from being sideways during the assembly process. Damage to the wall due to extrusion deformation;

(4) The axial self-sealing shaft sealing device involved in the present utility model has simple structure, ingenious design and remarkable effect;

(5) The axial self-sealing shaft sealing device involved in the utility model has a long service life, is easy to process and assemble, has a simple manufacturing process, can be mass-produced, has low cost, is highly practical, and is suitable for wide-scale promotion;

(6) In the compressor with the axial self-sealing shaft seal device, the shaft seal and the main shaft are matched with clearance, which solves the problems of large shaft power loss and high price due to the hard fit of the shaft seal in ordinary compressors.

Description of drawings

Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings:

Fig. 1 is the structural representation of the axial self-sealing shaft sealing device of the present invention;

2 is an enlarged schematic view of a partial structure of the axial self-sealing shaft sealing device of the present invention;

Fig. 3 is the structural schematic diagram 1 of the shaft seal of the utility model;

Fig. 4 is the structural representation 2 of the shaft seal of the utility model;

5 is a schematic cross-sectional view of the structure of the shaft seal of the present invention.

Detailed ways

The present utility model will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that, for those skilled in the art, some modifications and improvements can be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

Example 1

This embodiment provides an axial self-sealing shaft seal device, the structure of which is shown in Figures 1-5: it includes a main shaft 1, a shaft seal 2 and a bearing seat 3 sleeved on the main shaft 1, and the bearing seat 3. The shaft seal 2 is jacketed on the main shaft 1, and the end face of the inner cavity of the bearing seat 3 is flush with the upper end face of the shaft seal 2, and a back pressure cavity is formed between the shaft seal 2, the bearing seat 3 and the main shaft 1 4; the shaft seal 2 includes an accommodating cavity 21 and a casing cylinder 22, and the inner wall of the accommodating cavity 21 is provided with a plurality of annular grooves 23; a cavity is provided between the shaft seal 2 and the main shaft 1, so The cavity is alternately composed of a small annular cavity 5 and a large annular cavity 6, the large annular cavity 6 is composed of an annular groove 23 and the outer wall of the main shaft 1, and the small annular cavity 5 is composed of the accommodating cavity 21 except the annular cavity. The inner wall outside the groove 23 is formed with the outer wall of the main shaft 1; the outer wall and bottom of the outer shell cylinder 22 and the bearing seat 3 form an abutment surface 7, when the back pressure chamber 4 is under pressure, the pressure acts on the shaft seal 2 , and then transmitted to the contact surface 7 to form a contact seal between the shaft seal 2 and the bearing seat 3 .

Further, the shaft seal 2 has a structure with a large top and a small bottom, and the contact surface 7 formed by the outer wall of the casing cylinder 22 and the bearing seat 3 is inclined from top to bottom to the side of the main shaft 1 . The shaft seal 2 is arranged in a large upper and lower small structure to form a pressure angle, so that the pressure sealing performance formed by the shaft seal and the bearing seat is better.

Further, the upper end surface of the shaft seal 2 is further provided with a groove 24 , the groove 24 is formed between the outer wall of the accommodating cavity 21 and the inner wall of the outer casing 22 , and the opening of the groove 24 is formed. The end faces the back pressure chamber 4 . When the shaft seal is under pressure, the groove is deformed to the inner wall of the accommodating cavity and the outer wall of the outer casing, so that the shaft seal fits better with the bearing seat and the main shaft, and the sealing performance is strengthened; at the same time, the shaft seal is assembled during the assembly process. The inner side wall of the middle accommodating cavity will be deformed by the extrusion of the external force. The groove between the outer wall of the accommodating cavity and the inner wall of the outer casing can buffer the deformation of the side wall of the accommodating cavity to a great extent, thus effectively preventing the shaft seal from being assembled. The side wall is damaged due to extrusion deformation during the process.

Further, at least two annular grooves 23 are provided. The number of annular grooves is determined according to the height of the bearing seat. The more annular grooves are arranged, the stronger the sealing effect between the shaft seal and the main shaft will be, and the goal of zero leakage of refrigeration oil can be achieved.

Further, the width of the large annular cavity 6 is greater than the width of the small annular cavity 5 . The width of the large annular cavity and the small annular cavity is related to the structure and material of the shaft seal, the pressure on the shaft seal, and the flow rate. Generally, the smaller the width of the small annular cavity, the larger the width of the large annular cavity, the better.

Further, the width of the large annular cavity 6 is 10 times the width of the small annular cavity 5 .

Further, the annular groove 23 is any one of a concave triangular groove, an arc groove, a square groove, a rectangular groove, a trapezoidal groove or a polygonal groove. When the depths are different, the maximum depth when the annular groove is concave plus the width of the small annular cavity is the maximum width of the large annular cavity, and the width of the large annular cavity is 10 times the width of the small annular cavity, It means that the maximum width of the large annular cavity is 10 times the width of the small annular cavity.

Further, the main shaft 1 is in clearance fit with the shaft seal 2 , and the main shaft 1 is in clearance fit with the bearing seat 3 .

Further, the shaft seal 2 is made of polytetrafluoroethylene or polyether ether ketone material. It is elastic, deformed under pressure, and will stick to the bearing seat to form a good sealing effect.

Further, an accommodating groove for accommodating the shaft seal 2 is provided on the upper part of the accommodating cavity of the bearing seat 3 sleeved on the main shaft 1 , and the accommodating groove cooperates and seals with the outer wall and bottom of the casing cylinder 22 .

The working principle is: the refrigeration oil in the back pressure cavity leaks into the cavity between the shaft seal and the main shaft under the action of the pressure P; after the refrigeration oil is throttled through the small inlet of the small annular cavity, it enters the large annular cavity In the middle, the fluid forms a strong vortex in the large annular cavity, which reduces the pressure from the initial pressure P to P1, and the refrigeration oil passes through the next small annular cavity and the large annular cavity. Descending from P1 to P2, the leakage rate of refrigeration oil almost disappears completely, thus achieving the sealing effect.

This embodiment has the following beneficial effects:

(1) The axial self-sealing without contact between the shaft seal and the main shaft is realized, the shaft power loss is small, the sealing effect is good, and the leakage is zero, which is suitable for various liquid shaft seal devices;

(2) The shaft seal is set to a structure with a large upper and a small lower, forming a pressure angle, so that the pressure sealing performance formed by the shaft seal and the bearing seat is better;

(3) A groove is arranged on the shaft seal, so that the sealing effect between the shaft seal and the bearing seat and the main shaft is stronger. At the same time, the inner side wall of the shaft seal will be squeezed by external force during the assembly process and deformed. The grooves arranged between the outer wall and the inner wall of the outer casing can buffer the deformation of the side wall of the accommodating cavity to a great extent, thereby effectively preventing the damage of the side wall caused by the extrusion deformation during the assembly process of the shaft seal;

(4) Its structure is simple, the design is ingenious, and the effect is remarkable;

(5) Long service life, easy processing and assembly, simple manufacturing process, mass production, low cost, strong practicability, and suitable for large-scale promotion.

Example 2

This embodiment provides an axial self-sealing shaft sealing device, the structure of which is detailed in Embodiment 1.

This embodiment also provides a compressor with good sealing performance. In order to achieve the above purpose, this embodiment is achieved through the following technical solutions: a shaft sealing device including the aforementioned axial self-sealing is provided on the back pressure surface of the movable scroll of the compressor.

Further, the main shaft 1 is in clearance fit with the shaft seal 2 , and the main shaft 1 is in clearance fit with the bearing seat 3 .

For a compressor with an axial self-sealing shaft seal device, the shaft seal fits with the main shaft in clearance, which solves the problems of large shaft power loss and high price due to the perfect fit of the shaft seal in ordinary compressors.

The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and those skilled in the art can make various deformations or modifications within the scope of the claims, which do not affect the essential content of the present invention.

Claims (10)

1. The axial self-sealing shaft seal device is characterized by comprising a main shaft (1), a shaft seal (2) and a bearing seat (3), wherein the shaft seal (2) and the bearing seat (3) are sleeved on the main shaft (1), the bearing seat (3) is used for clamping the shaft seal (2) on the main shaft (1), the end surface of an inner cavity of the bearing seat (3) is flush with the upper end surface of the shaft seal (2), and a back pressure cavity (4) is formed between the shaft seal (2) and the main shaft (1) and between the bearing seat (3) and the main shaft (1); the shaft seal (2) comprises an accommodating cavity (21) and a shell barrel (22), and a plurality of annular grooves (23) are formed in the inner wall of the accommodating cavity (21); a cavity is arranged between the shaft seal (2) and the main shaft (1), the cavity is formed by small annular cavities (5) and large annular cavities (6) in an alternating mode, the large annular cavity (6) is formed by an annular groove (23) and the outer wall of the main shaft (1), and the small annular cavity (5) is formed by the inner wall of the accommodating cavity (21) except the annular groove (23) and the outer wall of the main shaft (1); the outer wall and the bottom of the shell barrel (22) and the bearing seat (3) form a butt joint surface (7), when the back pressure cavity (4) bears pressure, the pressure acts on the shaft seal (2) and is further transmitted to the butt joint surface (7), and contact sealing between the shaft seal (2) and the bearing seat (3) is formed.

2. The axial self-sealing shaft seal device according to claim 1, characterized in that the shaft seal (2) is of a large-top structure and a small-bottom structure, and an abutting surface (7) formed by the outer wall of the housing cylinder (22) and the bearing seat (3) is arranged obliquely from top to bottom toward the main shaft (1).

3. The axial self-sealing shaft seal device according to claim 1, characterized in that the upper end face of the shaft seal (2) is further provided with a groove (24), the groove (24) is formed between the outer wall of the accommodating cavity (21) and the inner wall of the housing cylinder (22), and the open end of the groove (24) faces the back pressure cavity (4).

4. Axial self-sealing shaft seal arrangement according to claim 1, characterized in that there are at least 2 of said annular grooves (23).

5. Axial self-sealing shaft seal arrangement according to claim 1, characterized in that the width of the large annular cavity (6) is larger than the width of the small annular cavity (5).

6. Axial self-sealing shaft seal arrangement according to claim 1, characterized in that the width of the large annular cavity (6) is 10 times the width of the small annular cavity (5).

7. Axial self-sealing shaft seal arrangement according to claim 1, characterized in that the main shaft (1) is clearance fitted with the shaft seal (2) and the main shaft (1) is clearance fitted with the bearing seat (3).

8. The axial self-sealing shaft seal arrangement according to claim 1, characterized in that the shaft seal (2) is made of polytetrafluoroethylene or polyetheretherketone material.

9. The axial self-sealing shaft seal device according to claim 1, characterized in that the bearing seat (3) is provided with a receiving groove for receiving the shaft seal (2) at the upper part of the receiving cavity of the main shaft (1), and the receiving groove is sealed with the outer wall and the bottom of the outer shell cylinder (22) in a matching way.

10. A compressor, characterized in that a shaft seal device comprising the axial self-sealing as claimed in any one of claims 1 to 9 is provided on a back pressure surface of an orbiting scroll.

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