Anti-rotation structure and oil-free scroll compressor thereof

Abstract

This utility model discloses an anti-rotation structure and its oil-free scroll compressor, comprising: a moving disc, on the outer circumferential side of which are at least three first protrusions; a housing, on the side of which adjacent to the moving disc are at least three second protrusions corresponding one-to-one with the first protrusions; and a flange eccentric sleeve connected to a first bearing installed in the second protrusions, wherein a cylindrical pin extending into the flange eccentric sleeve is installed in the first protrusion. This utility model has a simple structure. By changing the large clearance fit between the cylindrical pin and the ring sleeve to a small clearance fit between the cylindrical pin and the flange eccentric sleeve, the fit clearance is effectively reduced, significantly lowering the impact noise between the cylindrical pin and the mating parts. The small clearance fit enhances the stability of the moving pair, suppresses the overturning phenomenon of the moving disc caused by the large clearance, and improves the smoothness and reliability of the compressor operation. It combines the advantages of the pin sleeve anti-rotation structure and the three-crank structure.

Description

Technical Field

[0001] This utility model relates to the field of oil-free scroll compressor technology, specifically an anti-rotation structure and its oil-free scroll compressor. Background Technology

[0002] In scroll compressors, the motion of the moving disc is a translational motion around the center of the fixed disc without rotation. To achieve this motion, an anti-rotation mechanism is needed to constrain the rotational degree of freedom of the moving disc. Currently, the most widely used anti-rotation structures mainly include three types: cross-slip ring structure, pin sleeve structure, and three-crank crank structure.

[0003] Among the three structures, the cross-ring structure is simple in design and easy to assemble, making it the most manufacturable. The pin-sleeve structure is next, also relatively simple in design and lower in cost. The three-crank structure, however, is relatively complex and difficult to assemble. In terms of application environment, the cross-ring and pin-sleeve structures are mostly used in oil-lubricated scroll compressors because sliding friction exists between their moving parts, resulting in high frictional power consumption and severe wear under oil-free conditions, making long-term stable operation difficult. In contrast, the three-crank structure uses multiple bearings and eccentric cranks to guide the translational motion of the moving disc, with rolling friction as the primary motion mode, significantly reducing frictional power consumption and heat generation. Therefore, it is the most widely used in oil-free scroll compressors.

[0004] However, the three-crank crank structure has significant drawbacks: on the one hand, its anti-rotation mechanism typically requires about twelve bearings, resulting in a large number of parts and high manufacturing and assembly costs; on the other hand, the eccentric shaft of the eccentric crank is difficult to machine, the eccentricity accuracy is hard to control, and the consistency is poor, which is not conducive to mass production. While the pin-sleeve structure is simple in structure and has the lowest cost, it is essentially a sliding friction pair, which is prone to severe wear and noise problems under oil-free conditions; at the same time, there is a clearance between the pin and the sleeve, and as the operating time increases, the wear intensifies, which can easily lead to the overturning of the moving disc, resulting in a decrease in compressor sealing performance, reduced efficiency, and a significant increase in vibration and noise.

[0005] Therefore, existing technologies still lack an anti-rotation structure that can operate reliably in an oil-free environment while possessing advantages such as simple structure, low cost, low frictional power consumption, and high machining precision. To overcome the limitations of the aforementioned cross-slip ring, pin sleeve, and three-crank crank structures, an anti-rotation structure and its oil-free scroll compressor are proposed. Utility Model Content

[0006] The purpose of this invention is to provide an anti-rotation structure and its oil-free scroll compressor to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, this utility model provides the following technical solution: an anti-rotation structure, comprising:

[0008] The moving disk has at least three first protrusions distributed circumferentially on its outer side;

[0009] The housing has at least three second protrusions that correspond one-to-one with the first protrusion on the side of the housing near the moving disk;

[0010] An eccentric flange sleeve is connected to a first bearing installed in a second boss, and a cylindrical pin with its end extending into the eccentric flange sleeve is installed in the first boss.

[0011] As a further embodiment of this utility model: a bearing hole is provided on the side of the moving disk near the housing, and a second bearing is installed inside the bearing hole.

[0012] As a further embodiment of this utility model: the flange eccentric sleeve is provided with an eccentric hole that slides with the end of the cylindrical pin, and the eccentricity of the eccentric hole is equal to the rotation radius of the moving disc.

[0013] As a further embodiment of this utility model: the length of the cylindrical pin extending out of the first boss is 1.5 to 2.5 times the diameter of the cylindrical pin, and the end of the cylindrical pin is interference-fitted with the inner hole of the first boss.

[0014] As a further embodiment of this utility model: the flange eccentric sleeve is interference-fitted with the inner hole of the first bearing, and its outer diameter is smaller than the inner diameter of the outer ring of the first bearing.

[0015] As a further embodiment of this utility model: a vortex-shaped line is installed on the side of the moving disk away from the housing, and a sealing groove is opened on the end face of the vortex-shaped line away from the moving disk. An elastic strip of the moving disk is installed at the bottom of the sealing groove, and a sealing strip is provided in the sealing groove above the elastic strip of the moving disk.

[0016] An oil-free scroll compressor includes the aforementioned anti-rotation structure and further includes a motor, the motor being installed inside the housing, the output end of the motor passing through the housing and connected to the moving plate, and a counterweight being installed at the output end of the motor.

[0017] Compared with the prior art, the beneficial effects of this utility model are:

[0018] This application effectively reduces the clearance by changing the large clearance fit between the cylindrical pin and the ring sleeve to a small clearance fit between the cylindrical pin and the flange eccentric sleeve, significantly reducing the impact noise between the cylindrical pin and the mating parts. The small clearance fit enhances the stability of the moving pair, suppresses the overturning phenomenon of the moving disc caused by the large clearance, and improves the smoothness and reliability of the compressor operation. It combines the advantages of the pin sleeve anti-rotation structure and the three-crank structure, optimizing the transmission structure while retaining the anti-rotation function, further reducing the noise level. Compared with the complex design of multiple bearings and eccentric shafts in the three-crank structure, this structure simplifies the mechanical structure, reduces the number of bearings and the machining difficulty of the eccentric shaft, which helps to reduce manufacturing costs and improve assembly accuracy. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the oil-free scroll compressor of this utility model;

[0020] Figure 2 This is a schematic diagram of the moving disc of this utility model;

[0021] Figure 3 This is a cross-sectional view of the moving disc of this utility model;

[0022] Figure 4 This is a schematic diagram of the bottom of the moving plate of this utility model;

[0023] Figure 5 This is a cross-sectional schematic diagram of the flange eccentric sleeve of this utility model;

[0024] Figure 6 This is a schematic diagram of the flange eccentric sleeve of this utility model;

[0025] In the diagram: 100, moving disc; 101, first boss; 102, cylindrical pin; 103, scroll profile; 104, second bearing; 105, sealing groove; 106, moving disc elastic strip; 107, sealing strip; 200, housing; 201, second boss; 202, first bearing; 203, flange eccentric sleeve; 2031, eccentric hole; 300, motor; 400, counterweight. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] Please see Figure 1-6 In this embodiment of the invention, an anti-rotation structure includes:

[0028] The movable disk 100 has at least three first protrusions 101 distributed circumferentially on its outer side;

[0029] The housing 200 has at least three second protrusions 201 that correspond one-to-one with the first protrusion 101 on the side of the housing 200 adjacent to the moving disk 100;

[0030] The flange eccentric sleeve 203 is connected to the first bearing 202 installed in the second boss 201. A cylindrical pin 102 with its end extending into the flange eccentric sleeve 203 is installed in the first boss 101.

[0031] Specifically, the number of first bosses 101 and second bosses 201 is the same. In this embodiment, preferably, there are three first bosses 101. The three first bosses 101 are distributed on the outer side of the moving plate 100. Each first boss 101 is provided with a pin hole. Both openings of the pin hole are chamfered. The outer side of the first boss 101 is rounded. The end face of the first boss 101 near the housing 200 is surface treated (such as DLC, nickel plating, spraying polymer coating, etc. for friction reduction and wear resistance). The rounded corners and chamfers are to eliminate burrs and stress concentration, and extend the service life of the first boss 101.

[0032] The flange eccentric sleeve 203 is made of modified PEEK material or oil-impregnated powder metallurgy material. The modified PEEK material is used to reduce frictional noise between the cylindrical pin 102 and the flange eccentric sleeve 203, and to reduce frictional power consumption. The oil-impregnated powder metallurgy material has better precision control. When heated, the lubricating oil in the pores of the powder metallurgy material will be released, thereby reducing friction. After the temperature drops, the lubricating oil can be drawn back into the pores. It has good oil retention and can maintain a long service life.

[0033] The end face of the first boss 101 is in contact with the end face of the flange eccentric sleeve 203, forming a pair of sliding friction pairs. The two contact surfaces of the friction pair are made of matching friction-reducing and wear-resistant materials or surface treatment processes to effectively reduce the friction coefficient and reduce friction power consumption.

[0034] In this structure, the mass of the moving disc 100 and the axial gas force it experiences are ultimately transmitted to the inner ring of the first bearing 202 through the flange eccentric sleeve 203. Compared with the traditional pin sleeve structure where the end face of the moving disc 100 relies entirely on pure sliding friction to transmit the load, this application achieves partial rolling friction, significantly reducing friction loss and making this structure a promising candidate for application in oil-free scroll compressors.

[0035] For a scroll compressor with a three-crank structure, although the inner ring of its first bearing 202 also bears the mass of the moving disc and the axial gas force, such a structure usually requires multiple bearings (such as about twelve bearings in the anti-rotation mechanism), resulting in a high overall cost. At the same time, the machining of the eccentric crankshaft is difficult and costly, and the eccentricity accuracy is difficult to guarantee, resulting in poor consistency.

[0036] This application sets the eccentric structure on the flange eccentric sleeve 203. The eccentric hole 2031 on it is easier to process than the eccentric shaft, with high processing accuracy and good batch consistency, which is beneficial to mass production and quality control.

[0037] Depending on the mass and axial gas force acting on the moving disk 100, different types of bearings can be flexibly selected:

[0038] When the load is small, deep groove ball bearings are used to withstand both radial force and a certain amount of axial force.

[0039] When the load is large, angular contact ball bearings are used to better withstand the larger combined load (radial force and axial force).

[0040] Since bearings have inherent axial clearance, in order to ensure the axial sealing performance of the moving disc profile during compressor operation, this application provides a moving disc elastic strip 106 with axial elastic compensation function on the moving disc. Through its elastic deformation, it automatically compensates for the axial clearance, thereby effectively maintaining a good sealing effect and improving the efficiency and reliability of the compressor.

[0041] The above solution transforms the large clearance fit between the cylindrical pin 102 and the ring sleeve into a small clearance fit between the cylindrical pin 102 and the flange eccentric sleeve 203, thereby improving the impact noise between the cylindrical pin 102 and the ring sleeve and the overturning phenomenon of the moving disc caused by the large clearance fit. This structure combines the characteristics of the anti-rotation structure and the three-crank structure, reducing the noise and overturning effect of the structure, while also reducing the difficulty of machining multiple bearings and eccentric shafts in the three-crank structure.

[0042] Please see Figure 1 In one embodiment, preferably, the movable disk 100 has a bearing hole on the side near the housing 200, and a second bearing 104 is installed inside the bearing hole. The second bearing 104 is connected to the output shaft of the motor 300 through an eccentric shaft. When working, the motor 300 is started, and its output shaft drives the eccentric shaft to rotate. The eccentric shaft drives the movable disk 100 to move through the second bearing 104. Under the constraint of the anti-rotation structure, the movable disk 100 does not rotate, but rotates and translates around the rotation center of the eccentric shaft, thereby realizing the predetermined motion trajectory output.

[0043] Please see Figure 4-5In one embodiment, preferably, the flange eccentric sleeve 203 has an eccentric hole 2031 that slides with the end of the cylindrical pin 102. The eccentricity of the eccentric hole 2031 is equal to the radius of rotation of the moving plate 100. The length of the cylindrical pin 102 extending out of the first boss 101 is 1.5 to 2.5 times the diameter of the cylindrical pin 102. The end of the cylindrical pin 102 is interference-fitted with the inner hole of the first boss 101.

[0044] Please see Figure 1 In one embodiment, preferably, the flange eccentric sleeve 203 is interference-fitted with the inner hole of the first bearing 202, and the outer diameter of the flange eccentric sleeve 203 is smaller than the inner diameter of the outer ring of the first bearing 202. This avoids friction between the flange eccentric sleeve 203 and the outer ring of the first bearing 202 due to the axial clearance of the first bearing 202 and the axial force on the moving disc 100, which would increase power consumption. The cylindrical pin 102 is fitted with the flange eccentric sleeve 203 with a small clearance, and the flange eccentric sleeve 203 is interference-fitted with the inner ring of the first bearing 202. This fit can greatly reduce the overturning effect of the moving disc 100, thereby ensuring the performance of the oil-free compressor.

[0045] Please see Figure 1-3 In one embodiment, preferably, a vortex profile 103 is installed on the side of the moving disk 100 away from the housing 200. A sealing groove 105 is provided on the end face of the vortex profile 103 away from the moving disk 100. An elastic strip 106 of the moving disk is installed at the bottom of the sealing groove 105, which mainly serves to compensate for axial clearance and wear. A sealing strip 107 is provided in the sealing groove 105 above the elastic strip 106 of the moving disk.

[0046] An oil-free scroll compressor includes an anti-rotation structure and further includes a motor 300. The motor 300 is installed inside the housing 200. The output end of the motor 300 passes through the housing 200 and is connected to the moving plate 100. A counterweight 400 is also installed at the output end of the motor 300. The counterweight 400 is a conventional design in scroll compressors, and its main function is to balance the centrifugal force and balancing torque of the eccentric circular motion of the moving plate.

[0047] Although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0048] Therefore, the above description is only a preferred embodiment of this application and is not intended to limit the scope of this application; that is, all equivalent modifications made in accordance with the scope of the claims of this application shall be within the protection scope of the claims of this application.

Claims

1. An anti-rotation structure, characterized in that, include: The moving disk has at least three first protrusions distributed circumferentially on its outer side; The housing has at least three second protrusions that correspond one-to-one with the first protrusion on the side of the housing near the moving disk; An eccentric flange sleeve is connected to a first bearing installed in a second boss, and a cylindrical pin with its end extending into the eccentric flange sleeve is installed in the first boss.

2. The anti-rotation structure according to claim 1, characterized in that, A bearing hole is provided on the side of the moving disk near the housing, and a second bearing is installed inside the bearing hole.

3. The anti-rotation structure according to claim 1, characterized in that, The flange eccentric sleeve has an eccentric hole that slides with the end of the cylindrical pin, and the eccentricity of the eccentric hole is equal to the rotation radius of the moving disc.

4. The anti-rotation structure according to claim 3, characterized in that, The length of the cylindrical pin extending beyond the first boss is 1.5 to 2.5 times the diameter of the cylindrical pin, and the end of the cylindrical pin is interference-fitted with the inner hole of the first boss.

5. The anti-rotation structure according to claim 4, characterized in that, The flange eccentric sleeve is interference-fitted with the inner hole of the first bearing, and its outer diameter is smaller than the inner diameter of the outer ring of the first bearing.

6. The anti-rotation structure according to claim 1, characterized in that, A vortex-shaped line is installed on the side of the moving disk away from the housing. A sealing groove is opened on the end face of the vortex-shaped line away from the moving disk. An elastic strip of the moving disk is installed at the bottom of the sealing groove, and a sealing strip is arranged inside the sealing groove above the elastic strip of the moving disk.

7. An oil-free scroll compressor, characterized in that, The anti-rotation structure, including any one of claims 1-6, further includes a motor, the motor being installed inside the housing, the output end of the motor passing through the housing and connected to the moving plate, and a counterweight being installed at the output end of the motor.

Images