Piston assembly and compressor

Abstract

The piston assembly comprises a piston connecting rod and a piston, the piston is connected to the end of the piston connecting rod, at least one group of first oil guide grooves and one group of third oil guide grooves are formed in the outer surface of the piston, at least one group of annular grooves are formed in the outer surface of the piston, and boss structures are arranged on the inner walls of the annular grooves in the circumferential direction. When the piston ring is installed, the outer edge of the boss structure can be tilted towards one side of the boss structure. The piston ring is simple in structure, the boss structure is arranged, when the piston ring is sleeved in, under the influence of the boss structure, the piston ring tilts towards the boss, and when a piston reciprocates in a cylinder hole, the tilting position of the piston ring can play a better sealing role, so that the internal leakage rate of the compressor is reduced, the performance of the compressor is improved, and in addition, the service life of the compressor is prolonged. By arranging the oil guide groove, compressor oil can enter the inner surface of the piston ring through the oil guide groove, the piston ring is lubricated, and the service life of the compressor is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of compressor technology, specifically a piston assembly and a compressor. Background Technology

[0002] In automotive air conditioning systems, the compressor is the core component for achieving the refrigeration cycle. It provides temperature regulation for the vehicle interior by compressing low-temperature, low-pressure refrigerant gas and discharging high-temperature, high-pressure gas. Swashplate compressors are widely used in passenger vehicles because they can dynamically change the piston stroke by adjusting the swashplate angle, thus achieving automatic displacement control. When the compressor is running, the swashplate swings slightly, causing the piston to perform short-stroke reciprocating motion. As the compressor runs, the pressure in the exhaust chamber increases, while the pressure in the intake chamber decreases. The low-pressure port of the displacement control valve opens, further reducing the pressure within the swashplate chamber. When the force on the piston head exceeds the force on the piston back, the swashplate angle increases, the piston stroke increases, and the compressor reaches its maximum displacement. During this process, the piston rings must be able to seal against high-pressure gas entering the swashplate chamber. Poor sealing will prevent the compressor from reaching its maximum displacement in time, affecting the cooling effect. However, existing piston ring seals rely on the elasticity of the material itself and its fit with the cylinder bore. If the material lacks toughness or wears down over time, the sealing ability will decrease. Therefore, a piston assembly and compressor are proposed. Utility Model Content

[0003] The purpose of this invention is to provide a piston assembly and a compressor to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a piston assembly, comprising:

[0005] Piston connecting rod;

[0006] Piston, which is connected to the end of the piston rod;

[0007] At least one piston ring, which is fixed to the outer circumferential surface of the piston;

[0008] The outer surface of the piston has at least one set of first oil guide grooves and one set of third oil guide grooves, and at least one set of annular grooves. The inner wall of the annular groove is provided with a boss structure in the circumferential direction. When the piston ring is installed, the outer edge of the boss structure can be raised towards the side of the boss structure.

[0009] As a further embodiment of this utility model: the number of annular grooves is two, the two annular grooves are located at the two ends of the first oil guide groove, and are symmetrically distributed with the axis of the first oil guide groove as the center.

[0010] As a further embodiment of this utility model: the axial height difference between the top of the boss structure and the bottom of the annular groove is A, 0.05mm≦A≦0.25mm.

[0011] This utility model provides a compressor, which includes the piston assembly described above.

[0012] As a further aspect of this utility model, it includes:

[0013] Cylinder block, and

[0014] Front cover assembly and rear cover fixed to the cylinder block;

[0015] The cylinder body is provided with a swashplate connected to the front cover assembly. The swashplate is provided with a rocker plate connected to the piston connecting rod. The cylinder body is also formed with multiple cylinder bores that provide guidance and working space for the piston. A second oil guide groove is formed on the inner wall of the cylinder bore to facilitate the oil to reach the piston rings.

[0016] As a further embodiment of this utility model, the cylinder body and the rear cover are connected by a valve plate assembly.

[0017] As a further embodiment of this invention, the swashplate and the rocker plate are connected by a thrust needle roller bearing.

[0018] As a further embodiment of this utility model: the front cover assembly is provided with a main shaft that passes through the cylinder body and valve plate assembly and is connected to the rear cover.

[0019] As a further embodiment of this utility model, the main shaft, the front cover assembly, and the cylinder are all connected by bearings.

[0020] As a further embodiment of this utility model: the swashplate is sleeved on the outer surface of the main shaft and connected to the front cover assembly through a front thrust roller bearing.

[0021] Compared with the prior art, the beneficial effects of this utility model are:

[0022] This application incorporates a boss structure, which causes the piston rings to tilt upwards towards the boss when they are fitted. As the piston reciprocates inside the cylinder bore, the tilted part of the piston ring provides better sealing, thereby reducing the internal leakage rate of the compressor and improving its performance. Furthermore, by incorporating an oil guide groove, compressor oil can enter the inner surface of the piston ring through the groove, providing lubrication and extending the compressor's service life. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the piston of this utility model;

[0024] Figure 2This is a schematic diagram of the piston assembly of this utility model;

[0025] Figure 3 This is a cross-sectional view of the piston of this utility model;

[0026] Figure 4 This is a cross-sectional schematic diagram of the compressor of this utility model;

[0027] Figure 5 This is a schematic diagram of the cylinder bore on the compressor of this utility model;

[0028] In the diagram: 1. Cylinder block; 2. Front cover assembly; 3. Rear cover; 4. Valve plate assembly; 5. Main shaft; 6. Bearing; 7. Swashplate; 8. Thrust roller bearing; 9. Rocker plate; 10. Thrust needle roller bearing; 11. Piston connecting rod; 12. Piston; 13. Annular groove; 14. Boss structure; 15. First oil guide groove; 16. Piston ring; 17. Cylinder bore; 18. Second oil guide groove; 19. Third oil guide groove. Detailed Implementation

[0029] 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.

[0030] Please see Figure 1-3 In this embodiment of the present invention, a piston assembly includes:

[0031] Piston connecting rod 11;

[0032] Piston 12, which is connected to the end of piston rod 11;

[0033] At least one piston ring 16 is fixed to the outer peripheral surface of the piston 12;

[0034] The outer surface of the piston 12 has at least a set of first oil guide grooves 15 and a set of third oil guide grooves 19, and at least a set of annular grooves 13. The inner wall of the annular groove 13 is provided with a boss structure 14. When the piston ring 16 is installed, the outer edge of the boss structure 14 can be raised towards the side of the boss structure 14.

[0035] Specifically, the piston connecting rod 11 connects the piston 12 and the rocker plate 9, enabling the piston 12 to reciprocate within the cylinder bore 17. During this reciprocating motion, the piston 12 compresses the refrigerant. This design not only ensures the effectiveness of mechanical transmission but also achieves the crucial compression function in the refrigeration system. This structure is essential for maintaining the normal operation of the refrigeration system. The number of piston rings 16 is the same as the number of annular grooves 13. The piston rings 16 are fitted onto the outer circumferential surface of the annular grooves 13. The number of piston rings 16 and annular grooves 13 can be adjusted according to different application scenarios. The piston rings 16 can seal the cylinder bore. 17. To ensure no leakage of high-pressure refrigerant, the number of the first oil guide groove 15 and the third oil guide groove 19 can be adjusted according to different application scenarios. The third oil guide groove 19 is located on the piston 12 away from the piston connecting rod 11, and the positions of the third oil guide groove 19 and the first oil guide groove 15 correspond one-to-one, which facilitates the processing of the oil guide grooves during the initial processing. Secondly, external gas or fluid can enter one of the annular grooves 13 through the third oil guide groove 19, and then flow to the other annular groove 13 through the first oil guide groove 15. The inner wall of the annular groove 13 is provided with a boss structure 14, and the top of the boss structure 14 is connected to the annular groove. The axial height difference of the bottom surface of piston ring 13 is A, where 0.05mm ≤ A ≤ 0.25mm. This ensures that when piston ring 16 is fitted into the annular groove 13 on piston 12, the presence of the boss structure 14 causes piston ring 16 to tilt towards the boss 14. When piston 12 reciprocates inside cylinder bore 17, the tilted part of piston ring 16 can better seal, thereby reducing the internal leakage rate of compressor and improving compressor performance. Furthermore, this structure increases the contact friction of piston ring 16, preventing piston ring 16 from loosening due to long-term use. Additionally, the bottom of the tilted piston ring 16 has a certain space for gas or fluid to pass through. When the piston 12 reciprocates within the cylinder bore 17, the refrigerant gas is compressed. The gas then enters the space between the annular groove 13 and the piston ring 16 through the third oil guide groove 19. When the space between the annular groove 13 and the piston ring 16, as well as the first oil guide groove 15, are filled with gas, the piston ring 16 expands due to its elastic properties, thus supporting the piston ring 16. This makes the outer surface of the piston ring 16 fit more tightly against the inner wall of the cylinder bore 17, resulting in a better sealing effect. In addition, engine oil can enter the space between the annular groove 13 and the piston ring 16 through the third oil guide groove 19, providing lubrication for the piston ring 16.

[0036] Please see Figure 1-3In one embodiment, preferably, there are two annular grooves 13. The two annular grooves 13 are located at the two ends of the first oil guide groove 15 and are symmetrically distributed with the axis of the first oil guide groove 15 as the center. Piston rings 16 are fitted on both annular grooves 13. This design ensures that the gas or fluid entering either annular groove 13 can flow smoothly through the first oil guide groove 15 to the other annular groove 13. This layout not only ensures the smooth flow of gas or fluid, but also achieves two functions: first, to use gas to support the two piston rings 16, and second, to lubricate the two piston rings 16 through fluid.

[0037] Please see Figure 4-5 A compressor, the compressor including the above-described piston assembly, the compressor further including:

[0038] Cylinder block 1, and

[0039] Front cover assembly 2 and rear cover 3 fixed to cylinder body 1;

[0040] The cylinder body 1 is provided with a swash plate 7 connected to the front cover assembly 2. The swash plate 7 is provided with a rocker plate 9 connected to the piston connecting rod 11. The cylinder body 1 is also provided with multiple cylinder bores 17 to provide guidance and working space for the piston 12. A second oil guide groove 18 is formed on the inner wall of the cylinder bore 17 to facilitate the oil to reach the piston ring 16.

[0041] Specifically, a front cover assembly 2 is provided at the first end of the cylinder body 1, and the front cover assembly 2 is bolted to the first end of the cylinder body 1. A rear cover 3 is provided at the second end of the cylinder body 1, and a valve plate assembly 4 is provided between the cylinder body 1 and the rear cover 3. The cylinder body 1, valve plate assembly 4, and rear cover 3 are then connected and fixed by bolts. The swashplate 7 fixed on the main shaft 5 can adjust the stroke of the piston 12 by changing its angle, thereby changing the displacement of the compressor. The piston connecting rod 11, which is connected to the swashplate 7 through the rocker plate 9, can, under the action of the rocker plate 9, move the swashplate 7. The rotary motion is converted into the linear reciprocating motion of the piston connecting rod 11 (the working principle between the main shaft 5, swashplate 7, rocker plate 9 and piston 12 is existing technology and will not be elaborated here). The depth of the second oil guide groove 18 is 5-10mm. The compressor oil can enter the third oil guide groove 19 through the second oil guide groove 18 and then enter the outer surface of the piston ring 16. Together with the first oil guide groove 15 on the surface of the piston 12, it lubricates the inner and outer surfaces of the piston ring 16, reduces the coefficient of friction, reduces the starting torque value of the compressor, and ultimately improves the service life of the compressor.

[0042] Please see Figure 4In one embodiment, preferably, the swashplate 7 and the rocker plate 9 are connected by a thrust needle roller bearing 10, which helps to maintain a stable connection between the swashplate 7 and the rocker plate 9 and ensures that the two maintain the correct relative position and good contact state throughout the operation.

[0043] Please see Figure 4 In one embodiment, preferably, the front cover assembly 2 is provided with a main shaft 5 that passes through the cylinder block 1 and the valve plate assembly 4 and is connected to the rear cover 3. The two ends of the main shaft 5 are respectively connected to the engine and the compressor, which are used to transmit power.

[0044] Please see Figure 4 In one embodiment, preferably, the spindle 5 is connected to the front cover assembly 2 and the cylinder 1 via bearings 6, which helps to prevent the spindle 5 from being interfered with by the front cover assembly 2 and the cylinder 1 during operation.

[0045] Please see Figure 4 In one embodiment, preferably, the swash plate 7 is sleeved on the outer surface of the main shaft 5 and connected to the front cover assembly 2 through the thrust roller bearing 8. In this way, when the swash plate 7 rotates synchronously with the main shaft 5, the thrust roller bearing 8 can play a limiting role to prevent the swash plate 7 from making unnecessary axial movements. At the same time, it also ensures that the swash plate 7 is not disturbed by the front cover assembly 2 during rotation, thereby maintaining its normal operation.

[0046] 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.

[0047] 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. A piston assembly, characterized in that, include: Piston connecting rod; Piston, which is connected to the end of the piston rod; At least one piston ring, which is fixed to the outer circumferential surface of the piston; The outer surface of the piston has at least one set of first oil guide grooves and one set of third oil guide grooves, and at least one set of annular grooves. The inner wall of the annular groove is provided with a boss structure in the circumferential direction. When the piston ring is installed, the outer edge of the boss structure can be raised towards the side of the boss structure.

2. The piston assembly according to claim 1, characterized in that, The number of annular grooves is two, and the two annular grooves are located at the two ends of the first oil guide groove, and are symmetrically distributed with the axis of the first oil guide groove as the center.

3. The piston assembly according to claim 1, characterized in that, The axial height difference between the top of the boss structure and the bottom of the annular groove is A, where 0.05mm≦A≦0.25mm.

4. A compressor, characterized in that, The compressor includes the piston assembly as described in any one of claims 1-3.

5. The compressor according to claim 4, characterized in that, include: Cylinder block, and Front cover assembly and rear cover fixed to the cylinder block; The cylinder body is provided with a swashplate connected to the front cover assembly. The swashplate is provided with a rocker plate connected to the piston connecting rod. The cylinder body is also formed with multiple cylinder bores that provide guidance and working space for the piston. A second oil guide groove is formed on the inner wall of the cylinder bore to facilitate the oil to reach the piston rings.

6. The compressor according to claim 5, characterized in that, The cylinder block and the rear cover are connected by a valve plate assembly.

7. The compressor according to claim 5, characterized in that, The swash plate and the rocker plate are connected by a thrust needle roller bearing.

8. The compressor according to claim 6, characterized in that, The front cover assembly contains a main shaft that passes through the cylinder block and valve plate assembly and connects to the rear cover.

9. The compressor according to claim 8, characterized in that, The main shaft is connected to the front cover assembly and the cylinder block via bearings.

10. The compressor according to claim 8, characterized in that, The swash plate is fitted onto the outer surface of the main shaft and is connected to the front cover assembly via a front thrust roller bearing.

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