CN113202750A

CN113202750A - Semi-sealed scroll compressor

Info

Publication number: CN113202750A
Application number: CN202110481236.1A
Authority: CN
Inventors: 汤熙华; 陈登科; 伍海浩; 李继泰
Original assignee: Hunan Maigu Technology Co ltd
Current assignee: Hunan Maigu Technology Co ltd
Priority date: 2021-04-30
Filing date: 2021-04-30
Publication date: 2021-08-03

Abstract

The invention discloses a semi-closed scroll compressor, which comprises a frame, a movable scroll and a crankshaft, wherein the crankshaft is pivoted with a bearing hole on the frame, a back pressure cavity is formed between the frame, the back surface of the movable scroll and the crankshaft, and a damping structure for damping lubricating oil flowing out of the back pressure cavity is arranged between the crankshaft and the bearing hole. The invention controls the outflow rate of the lubricating oil in the back pressure cavity through the damping structure between the bearing hole and the crankshaft, thereby achieving the purpose of controlling the pressure of the back pressure cavity.

Description

Semi-sealed scroll compressor

Technical Field

The invention relates to the technical field of scroll compressors, in particular to a semi-sealed scroll compressor.

Background

The scroll compressor is generally composed of a casing, a fixed scroll, an orbiting scroll, a frame assembly, a back pressure pad, a crankshaft, a motor, etc. The frame is fixed in the shell, the fixed scroll disk is fixed on the frame, the motor drives the movable scroll disk to run through the crankshaft, low-pressure refrigerant gas in the shell is sucked and compressed to high-pressure gas to be discharged.

At present, in order to improve volumetric efficiency in compression, a floating structure of a movable scroll is mostly adopted. Namely, a back pressure cavity with intermediate pressure is formed between the frame, the back surface of the movable scroll and the crankshaft. The high pressure lubricating oil is led into the back pressure cavity from the exhaust side via the throttle channel, and the engine base has exhaust hole, through which the oil in the back pressure cavity is returned to the low pressure suction cavity inside the casing and is sucked, compressed and exhausted for circulation. The size of the discharge hole determines the pressure in the back pressure cavity, and the pressure of the back pressure cavity is usually larger than the axial gas force generated when the movable and fixed scroll disks are compressed, so that the movable scroll disk floats towards the fixed scroll disks, the gap between tooth tops of the scroll disks is eliminated, and the purpose of improving the volume efficiency is achieved. However, to control the pressure in the back pressure chamber properly, the hole diameter of the exhaust hole on the frame should not be too large, and is usually as small as possible. Accordingly, the discharge hole of the compressor is easily blocked by impurities such as aluminum chips, copper chips and oil sludge in the system during the working process due to the small aperture. The pressure of the back pressure cavity is overlarge, so that the friction loss between the movable and fixed scroll disks is increased, the power consumption of the compressor is increased, the efficiency is reduced, and meanwhile, the abrasion of the movable and fixed scroll disk parts is aggravated.

Further, structural sealing is achieved between the engine base and the crankshaft through a shaft seal, a lip opening of the shaft seal faces to the back pressure cavity side, and under the action of pressure, the inner side and the outer side of the shaft seal are expanded tightly, so that a sealing effect is achieved. However, the shaft seal also brings certain friction loss while playing a sealing effect, and the shaft seal mounting structure needs to be added on the machine base, so that the structure is complex and the cost is increased.

Furthermore, the top end of the movable vortex disk and the top end of the fixed vortex disk of the compressor are additionally provided with tooth top sealing strip structures, so that the tooth top sealing strips float under the action of high-pressure gas in the core part during operation, and the floating tooth top sealing strips can prevent the leakage of axial gap gas. The sealing strip should be lubricious for the requirements of the sealing strip's operating environment. If the sealing strip can receive abnormal wear because of lubricated badly, the lubricated sealing of not having oil simultaneously can lead to actuating, the axial leakage of fixed vortex disk is serious, will reduce compressor work efficiency even inefficacy. At present, the tooth top sealing strip of the fixed scroll is lubricated by a groove at the position of a core part of the fixed scroll for storing oil and lubricating the tooth top sealing strip, but the gap between the movable scroll and the fixed scroll is very small, so that the oil supply quantity of the structure is very limited, and even under the severe high-pressure working environment, the oil for sealing the end face of the scroll and the oil for lubricating the tooth top sealing strip cannot be met at all.

Disclosure of Invention

The present invention is directed to a semi-hermetic scroll compressor to solve the above problems.

In order to achieve the purpose, the invention discloses a semi-closed scroll compressor, which comprises a rack, a movable scroll and a crankshaft, wherein the crankshaft is pivoted with a bearing hole in the rack, a back pressure cavity is formed among the rack, the back surface of the movable scroll and the crankshaft, a damping structure for damping lubricating oil flowing out of the back pressure cavity is arranged between the crankshaft and the bearing hole, and the flowing speed of the lubricating oil in the back pressure cavity is controlled through the damping structure between the bearing hole and the crankshaft, so that the purpose of controlling the pressure of the back pressure cavity is achieved.

Furthermore, the damping structure is a damping groove arranged on the outer wall of the crankshaft or the inner wall of the bearing hole, one end of the damping groove is communicated with the backpressure cavity, and the other end of the damping groove is located in the bearing hole.

Further, the damping groove is arranged on the outer wall of the crankshaft, the damping groove is opposite to the inner wall of the bearing hole, and the damping groove is a spiral groove which spirally extends along the circumferential direction of the crankshaft.

Further, the spiral number of turns of the spiral groove is greater than or equal to one turn.

Furthermore, the spiral direction of the spiral groove is the same as the rotation direction of the crankshaft so as to generate a thrust force for the lubricating oil in the spiral groove to move to the back pressure cavity.

Furthermore, an annular groove is formed in the crankshaft and communicated with the back pressure cavity, and one end of the spiral groove is communicated with the annular groove.

Further, still include with the complex of whirlpool dish of deciding of whirlpool dish, one side of deciding the whirlpool dish is provided with the seal groove, there is the oil gallery in the seal groove, the opposite side of deciding the whirlpool dish is provided with the vortex dish tooth, the top of vortex dish tooth is provided with the tooth top groove that is used for installing the sealing strip, decide the whirlpool dish and still be provided with sealing strip lubrication channel, the sealing strip lubrication channel's one end with the tooth top groove is connected, the other end with the oil gallery is connected.

Further, the sealing strip lubricating channel comprises a fixed scroll oil hole and a fixed scroll oil groove, the fixed scroll oil hole axially penetrates through the tooth top groove, one end of the fixed scroll oil groove is connected with the oil return hole, and the other end of the fixed scroll oil groove is connected with the fixed scroll oil hole.

Further, be provided with the boss in the seal groove, the oil return hole sets up the one end of boss, decide the whirlpool dish oilhole and set up the other end of boss, decide the whirlpool dish oil groove setting and be in the upside of boss.

Furthermore, a sealing strip is installed in the tooth top groove, and a sealing strip oil hole penetrates through the sealing strip along the axial direction of the fixed scroll disk.

Compared with the prior art, the invention has the advantages that:

the invention controls the outflow rate of the lubricating oil in the back pressure cavity through the damping structure between the bearing hole and the crankshaft, thereby achieving the purpose of controlling the pressure of the back pressure cavity. Furthermore, the damping structure is arranged as a spiral groove on the crankshaft, a resistance is applied to oil flowing through a bearing gap through the spiral groove, an oil film is formed in the bearing gap, good lubricating and sealing effects are achieved, the pressure in the backpressure cavity is kept stable, the oil film also bears part of the load of the shaft, the load of the main bearing is reduced, and the service life of the main bearing is prolonged. Meanwhile, the arrangement of the spiral groove also avoids the filth blockage phenomenon caused by impurities in the discharge channel of the back pressure cavity, and meanwhile, the friction resistance brought by the shaft seal is avoided, so that the input work of the compressor is reduced, and the efficiency is improved.

Furthermore, the fixed scroll disk of the invention is provided with a sealing strip lubricating channel communicated with the tooth top groove and the oil return hole, so that part of oil return of the oil return hole is guided into the tooth top groove, thereby facilitating the full lubrication of the sealing strip in the tooth top groove, further reducing the abrasion of the sealing strip and prolonging the service life of the sealing strip; furthermore, the scroll compressor provided with the fixed scroll can ensure the overall working efficiency of the compressor in the working process, and the service life of the compressor is prolonged.

The present invention will be described in further detail below with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic sectional view of the back portion of a semi-hermetic scroll compressor as disclosed in a preferred embodiment of the present invention;

FIG. 2 is an axial schematic view of a crankshaft of the semi-hermetic scroll compressor disclosed in accordance with the preferred embodiment of the present invention;

FIG. 3 is a schematic front view of the fixed scroll of the semi-hermetic scroll compressor disclosed in the preferred embodiment of the present invention;

FIG. 4 is a schematic sectional view A-A of FIG. 3;

FIG. 5 is a schematic cross-sectional view B-B of FIG. 3;

FIG. 6 is a schematic bottom view of the fixed scroll of the semi-hermetic scroll compressor disclosed in the preferred embodiment of the present invention;

fig. 7 is an enlarged schematic view at a of fig. 6.

Illustration of the drawings:

1. a frame; 11. a bearing bore;

2. a movable scroll pan;

3. a crankshaft; 31. a helical groove; 32. an annular groove;

4. a fixed scroll pan; 41. a sealing groove; 42. an oil return hole; 43. a scroll tooth; 44. a tooth top groove; 45. a seal strip lubrication channel; 451. a fixed scroll oil hole; 452. a fixed scroll oil groove; 46. a boss;

5. a housing; 51. a front cover;

6. a back pressure chamber;

7. an exhaust chamber;

9. a motor;

10. a sealing strip; 101. and the sealing strip oil hole.

Detailed Description

The embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways as defined and covered by the claims.

As shown in fig. 1-7, the embodiment of the present invention discloses a semi-sealed scroll compressor, which comprises a frame 1, a movable scroll 2 and a crankshaft 3, and further comprises a fixed scroll 4 engaged with the movable scroll 2, and a motor 9 driving the crankshaft 3 to rotate, both of which are disposed in a housing 5 of the scroll compressor, the crankshaft 3 is pivoted with a bearing hole 11 on the frame 1, a back pressure chamber 6 is formed between the frame 1, the back surface of the movable scroll 2 and the crankshaft 3, an exhaust chamber 7 is formed between a front cover 51 of the housing 5 and the fixed scroll 4, the exhaust chamber 7 and the back pressure chamber 6 are communicated with each other through an oil return hole 42, so as to introduce high-pressure lubricant in the exhaust chamber 7 into the back pressure chamber 6, a damping structure for damping lubricant flowing out from the back pressure chamber 6 to between the crankshaft 3 and the bearing hole 11 is disposed between the crankshaft 3 and the bearing hole 11, the damping structure may be a hole structure, a groove structure or other various manners, therefore, the outflow rate of the lubricating oil in the back pressure cavity 6 is controlled through the damping structure, and the purpose of controlling the pressure of the back pressure cavity 6 is achieved.

Wherein, the damping structure is the damping groove of setting on the outer wall of bent axle 3 or the inner wall of dead eye 11, and the one end and the back pressure chamber 6 intercommunication of damping groove, the other end are located dead eye 11, see figure 1, the axial length of damping groove is shorter than the axial length of dead eye 11 promptly, the edge of dead eye 11 right-hand member is arrived to the one end of damping groove, but the other end does not arrive the edge of dead eye 11 left end. The damping slot may have various configurations, such as a linear slot, a curved slot, etc. In the present embodiment, for convenience of processing, a damping groove is provided on an outer wall of the crankshaft 3, the damping groove being opposed to an inner wall of the bearing hole 11. Further, the damping groove is a spiral groove 31 extending spirally along the circumferential direction of the crankshaft 3, so that one turning process can be completed.

In this embodiment, the spiral number of the spiral groove 31 is greater than or equal to one, usually one, so as to perform a sealing function similar to a shaft seal, and if less than one, a complete sealing ring cannot be formed in the circumferential direction of the crankshaft 3, so that a sealing effect cannot be achieved.

In this embodiment, the spiral direction of the spiral groove 31 is set to generate a thrust force to the lubricant in the spiral groove 31 moving into the back pressure chamber 6 when the crankshaft 3 rotates, specifically, when the crankshaft 3 rotates at the crank throw side, if the crankshaft 3 rotates counterclockwise, the spiral groove 31 rotates left, and if the crankshaft 3 rotates clockwise, the spiral groove 31 rotates right, so as to generate a damping effect to the flowing oil, control the flowing speed of the oil in the back pressure chamber 6, and achieve the purpose of controlling the pressure in the back pressure chamber 6.

In this embodiment, the crankshaft 3 is provided with an annular groove 32, the annular groove 32 is communicated with the back pressure chamber 6, and one end of the spiral groove 31 is communicated with the annular groove 32, so that the oil inlet end of the damping groove can be prevented from being blocked, and on the other hand, from the starting point of the machining process, the tool withdrawal during the thread turning is facilitated, and the starting point of the machining of the spiral groove 31 can also be used.

In the embodiment, a fixed scroll disk 4 is included, the fixed scroll disk 4 and the movable scroll disk 2 form a compression cavity, a sealing groove 41 is arranged on one side of the fixed scroll disk 4, the sealing groove 41 is used for installing a sealing element, the sealing groove 41 is annularly arranged, an oil return hole 42 is formed in the sealing groove 41, in the working process of the compressor, oil coming in through a front cover filter screen flows into the oil return hole 42 of the fixed scroll disk 4, a scroll disk tooth 43 is arranged on the other side of the fixed scroll disk 4 and is used for being matched with the movable scroll disk 2 to compress air, an addendum groove 44 used for installing a sealing strip 10 is arranged at the top of the scroll disk tooth 43 and is a generally rectangular groove, a sealing strip lubrication channel 45 is further arranged on the fixed scroll disk 4, one end of the sealing strip lubrication channel 45 is connected with the addendum groove 44, and the other end is connected with the oil return hole 42. By arranging the sealing strip lubricating channel 45 communicated with the tooth top groove 44 and the oil return hole 42, part of oil return of the oil return hole 42 is guided into the tooth top groove 44, so that the sealing strip in the tooth top groove 44 is sufficiently lubricated, the abrasion of the sealing strip 10 is reduced, and the service life of the sealing strip 10 is prolonged.

In the present embodiment, when the seal lubrication passage 45 is formed in detail, the seal lubrication passage 45 is divided into two stages in the axial direction and the radial direction, and includes the fixed scroll oil hole 451 and the fixed scroll oil groove 452, and is formed by machining or casting, the fixed scroll oil hole 451 axially penetrates the tooth top groove 44, one end of the fixed scroll oil groove 452 is connected to the oil return hole 42, and the other end is connected to the fixed scroll oil hole 451.

In the present embodiment, in order to prevent the oil return hole 42, the fixed scroll oil hole 451 and the fixed scroll oil groove 452 from being blocked by the sealing member in the sealing groove 41, the boss 46 is disposed in the sealing groove 41, the boss 46 is integrally cast, the boss 46 is disposed along the length direction of the sealing groove 41 and is disposed in the middle of the width direction of the sealing groove 41, which facilitates the arrangement of the sealing member around the boss 46, the oil return hole 42 is disposed at one end of the boss 46, the fixed scroll oil hole 451 is disposed at the other end of the boss 46, and the fixed scroll oil groove 452 is disposed at the upper side of the boss 46, so that the input ports of the oil return hole 42, the fixed scroll oil hole 451 and the fixed scroll oil groove 452 are raised, and a better sealing is achieved.

In the present embodiment, in order to facilitate uniform spreading of the lubricating oil flowing out of the fixed scroll oil hole 451 toward both ends along the tooth top groove 44, one end of the fixed scroll oil hole 451 connected to the tooth top groove 44 is provided at a middle position in the longitudinal direction of the tooth top groove 44.

In this embodiment, the seal strip 10 is installed in the tooth top groove 44, and the seal strip 10 is provided with the seal strip oil hole 101 along the axial direction through of the fixed scroll, so that the lubricating oil at the bottom of the tooth top groove 44 can flow to the contact surface between the seal strip 10 and the movable scroll through the seal strip oil hole 101, and further, because the seal strip 10 is fully lubricated, the working efficiency of the compressor is ensured, the service life of the compressor is prolonged, and for convenience of uniform diffusion of the lubricating oil flowing out of the seal strip oil hole 101 to both ends along the tooth top groove 44, the seal strip oil hole 101 is arranged at the middle position of the seal strip 10 in the length direction.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present invention, or modify equivalent embodiments to equivalent variations, without departing from the scope of the invention, using the teachings disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.

Claims

1. A semi-closed scroll compressor comprises a frame (1), a movable scroll (2) and a crankshaft (3), wherein the crankshaft (3) is pivoted with a bearing hole (11) in the frame (1), and a back pressure cavity (6) is formed between the frame (1), the back of the movable scroll (2) and the crankshaft (3), and is characterized in that a damping structure used for damping lubricating oil flowing out of the back pressure cavity (6) is arranged between the crankshaft (3) and the bearing hole (11).

2. Semi-hermetic scroll compressor according to claim 1, characterized in that the damping structure is a damping groove provided on the outer wall of the crankshaft (3) or the inner wall of the bearing hole (11), one end of the damping groove communicating with the back pressure chamber (6) and the other end being located in the bearing hole (11).

3. Semi-hermetic scroll compressor according to claim 2, characterized in that the damping groove is provided on the outer wall of the crankshaft (3), the damping groove being opposite to the inner wall of the bearing hole (11).

4. A semi-hermetic scroll compressor according to claim 3, wherein the damping groove is a spiral groove (31) spirally extending along a circumferential direction of the crankshaft (3), and a number of turns of the spiral groove (31) is greater than or equal to one turn.

5. Semi-hermetic scroll compressor according to claim 4, characterized in that the spiral direction of the spiral groove (31) is arranged to generate a thrust force for the lubricant in the spiral groove (31) moving into the back pressure chamber (6) when the crankshaft (3) rotates.

6. Semi-hermetic scroll compressor according to claim 4, characterized in that an annular groove (32) is provided on the crankshaft (3), the annular groove (32) communicating with the back pressure chamber (6), one end of the spiral groove (31) communicating with the annular groove (32).

7. The semi-closed scroll compressor according to any one of claims 1 to 6, further comprising a fixed scroll (4) matched with the movable scroll (2), wherein a sealing groove (41) is formed in one side of the fixed scroll (4), an oil return hole (42) is formed in the sealing groove (41), scroll teeth (43) are arranged on the other side of the fixed scroll (4), a tooth top groove (44) for installing a sealing strip (10) is formed in the top of each scroll tooth (43), a sealing strip lubricating channel (45) is further formed in the fixed scroll (4), one end of the sealing strip lubricating channel (45) is connected with the tooth top groove (44), and the other end of the sealing strip lubricating channel is connected with the oil return hole (42).

8. A semi-hermetic scroll compressor according to claim 7, wherein the sealing strip lubrication passage (45) includes a fixed scroll oil hole (451) and a fixed scroll oil groove (452), the fixed scroll oil hole (451) axially penetrates to the tooth top groove (44), one end of the fixed scroll oil groove (452) is connected to the oil return hole (42), and the other end is connected to the fixed scroll oil hole (451).

9. The semi-hermetic scroll compressor according to claim 8, wherein a boss (46) is provided in the sealing groove (41), the oil return hole (42) is provided at one end of the boss (46), the fixed scroll oil hole (451) is provided at the other end of the boss (46), and the fixed scroll oil groove (452) is provided at an upper side of the boss (46).

10. The semi-hermetic scroll compressor according to claim 8, wherein a seal strip (10) is installed in the tooth top groove (44), and a seal strip oil hole (101) is penetratingly provided in the seal strip (10) along an axial direction of the fixed scroll (4).