A piston structure for a refrigeration compressor

Abstract

The utility model discloses a piston structure for a refrigeration compressor, which belongs to the field of refrigeration compressors and comprises a piston head installed in a cylinder hole, wherein a friction pair is arranged on the piston head, and a lubrication structure is arranged at the friction pair, and the lubrication structure is a recessed structure arranged on the surface of the piston head; firstly, a small amount of local oil storage can be achieved through a cavity formed at the recessed part, thereby increasing the lubrication effect between the piston head and the cylinder hole; secondly, the recessed structure reduces the contact area between the piston head and the cylinder hole, further reducing the energy consumed by friction, thereby solving the problem in the prior art that the friction generated between the piston head and the cylinder hole during the operation of the compressor is relatively large, resulting in a significant impact on the performance of the compressor.

Description

Technical Field

[0001] The utility model relates to the field of refrigeration compressors, in particular to a piston structure for refrigeration compressors. Background Art

[0002] The refrigeration principle of a refrigerator is to compress the refrigerant into a high-temperature and high-pressure gas through a compressor, and then convert it into a high-pressure liquid through the heat dissipation of the condenser and flow into the evaporator. The refrigerant in the evaporator absorbs heat and becomes a low-temperature and low-pressure gas, thereby achieving the refrigeration effect. Therefore, the compressor is the core component of the refrigerator. If the performance of the compressor is not high, it will not only affect the refrigeration effect, but also increase the energy consumption of the refrigerator and affect the energy efficiency of the refrigerator. For the performance of the compressor, the main assessment indicator is the energy efficiency ratio, which is the ratio of the cooling capacity measured to the input power when the compressor is running under the specified test conditions. Its unit is W / W.

[0003] In a compressor, the main factor affecting input power is the friction loss between mechanical parts. Friction loss includes friction and wear between multiple parts such as the piston and the crankcase cylinder bore, the crankshaft and the crankshaft bore of the crankcase. For existing reciprocating piston compressors, the friction loss between the piston and the crankcase cylinder bore accounts for a high proportion of all mechanical friction losses. Therefore, reducing the friction loss between the piston and the crankcase cylinder bore can achieve the performance of the compressor.

[0004] For example, the "crankcase lubrication structure for refrigeration compressor" disclosed in the Chinese patent literature has a publication number of CN217481493U, which includes a housing, a crankshaft body, a connecting rod, a piston, and a fixing pin. The crankshaft body is rotatably connected to the housing, one end of the connecting rod is rotatably connected to the crankshaft body, and the other end of the connecting rod is rotatably connected to the fixing pin. The fixing pin is fixed to the piston. The piston is arranged in the cylinder hole of the housing, the cylinder hole is arranged horizontally, and the end of the cylinder hole close to the crankshaft body is the tail. A U-shaped groove is arranged above the tail of the cylinder hole for making way for the fixing pin. An oil storage groove is arranged above the cylinder hole, and the U-shaped groove intersects with the oil storage groove. The height of the oil storage groove is consistent with the height of the oil trace line when the crankshaft body is oiled at low speed. The disadvantage of this patent is that when the piston moves in the cylinder hole, due to the friction with the cylinder hole, the input power required by the compressor increases, and the performance of the compressor is affected. Utility Model Content

[0005] The utility model aims to overcome the problem in the prior art that during the operation of the compressor, the friction between the piston head and the cylinder hole is large, which causes a significant impact on the performance of the compressor. A piston structure for a refrigeration compressor is provided to improve the performance of the compressor by reducing the friction between the piston head and the cylinder hole.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] The utility model discloses a piston structure for a refrigeration compressor, comprising a piston head installed in a cylinder hole, a friction pair being arranged on the piston head, a lubrication structure being a concave structure arranged on the surface of the piston head.

[0008] By providing a concave lubrication structure on the friction pair of the piston head, two advantages are achieved at the same time. Firstly, a small amount of oil can be stored locally through the cavity formed at the concave part, thereby increasing the lubrication effect between the piston head and the cylinder hole; secondly, the concave structure reduces the contact area between the piston head and the cylinder hole, further reducing the energy consumed by friction.

[0009] Preferably, the lubrication structure is evenly arranged in the circumferential direction of the piston head. By evenly arranging the lubrication structure in the circumferential direction of the piston head, each position in the circumferential direction of the piston head can be fully lubricated, which can improve the lubrication effect on the one hand, and avoid the torque generated by the uneven force at various positions in the circumferential direction of the piston head on the other hand.

[0010] Preferably, the lubrication structure is a plurality of circular pits.

[0011] Preferably, the lubrication structure is a plurality of strip grooves, and the length direction of the strip grooves is parallel to the axial direction of the piston head.

[0012] Preferably, the lubrication structure is an annular groove surrounding the piston head in the circumferential direction. The annular groove can ensure that each position in the circumferential direction of the piston head can be fully lubricated. At the same time, since the oil can move in the circumferential direction, the situation of local oil shortage is avoided.

[0013] Preferably, there are several annular grooves, which are spaced apart in the axial direction of the piston head. The lubrication effect can be increased by spaced apart multiple annular grooves.

[0014] Preferably, a piston pin is provided in the piston head, and the piston pin is connected to the crankshaft of the compressor via a connecting rod. The transmission between the piston head and the crankshaft is realized through this structure.

[0015] Preferably, a pin hole is provided in the piston head, the pin hole is located in the radial direction of the piston head, and the piston pin is installed in the pin hole.

[0016] Preferably, the piston head is also provided with a pin hole annular groove surrounding the piston head in the circumferential direction, and lubrication of the pin hole position can be achieved through the pin hole annular groove.

[0017] Therefore, the utility model has the following beneficial effects: (1) a small amount of local oil storage can be achieved through the cavity formed in the depression, thereby increasing the lubrication effect between the piston head and the cylinder hole; (2) the contact area between the piston head and the cylinder hole is reduced, further reducing the energy consumed by friction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the utility model in a compressor.

[0019] Figure 2 It is a cross-sectional schematic diagram of the utility model in a compressor.

[0020] Figure 3 It is a front view schematic diagram of the piston head of the first embodiment of the utility model.

[0021] Figure 4 It is a front view schematic diagram of the piston head of the second embodiment of the utility model.

[0022] Figure 5 It is a front view schematic diagram of the piston head of the third embodiment of the utility model.

[0023] In the figure: crankshaft structure 1 piston structure 2 connecting rod transmission structure 3 piston head 4 lubrication structure 5 piston pin 6 pin hole 7 pin hole ring groove 8 oil storage part 9. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[0025] Embodiment 1, as Figure 1-3 As shown, a piston structure 2 for a refrigeration compressor is used in a refrigerator refrigeration compressor. The compressor includes a crankshaft structure 1, a piston structure 2, and a connecting rod transmission structure 3 connecting the two. The connecting rod transmission structure 3 includes a connecting rod.

[0026] The piston structure 2 includes a piston head 4 installed in the cylinder hole of the compressor. The piston head 4 is roughly cylindrical in shape, with chamfers at both ends and is arranged coaxially with the cylinder hole. The cylinder hole is provided with a limiting surface on the side facing the crankshaft structure 1, so as to limit the piston head 4 and prevent it from escaping from the cylinder hole. The piston head 4 is provided with a friction pair on the outer surface of the part far from the connecting rod, and the friction pair is provided with a lubrication structure 5. By setting the tolerance of the piston head 4 at different positions in the axial direction, when the piston head 4 moves back and forth in the cylinder hole, the friction force is mainly concentrated at the position where the friction pair is located.

[0027] The lubricating structure 5 is evenly arranged in the circumferential direction of the piston head 4. Specifically, the lubricating structure 5 is a plurality of circular pits, which are densely arranged on the outer surface of the piston head 4. The parts without depressions between the circular pits form a new friction pair. A cavity that can accommodate oil is formed in the circular pit. It produces two effects. First, through the cavity formed at the depression, a small amount of local oil storage can be achieved, increasing the lubrication effect between the piston head 4 and the cylinder hole; second, the depression structure reduces the contact area between the piston head 4 and the cylinder hole, further reducing the energy consumed by friction. The circumferentially evenly distributed form can make each position of the piston head 4 in the circumferential direction fully lubricated. On the one hand, it can improve the lubrication effect, and on the other hand, it can also avoid the piston head 4 from generating torque due to uneven force at various places in the circumferential direction. Further, the circular recesses are not only continuously arranged in the circumferential direction, but also have a plurality of layers in the axial direction. In this embodiment, the specific number of layers is nine. In actual production, the specific number of layers can be adaptively adjusted according to the size of the piston head 4.

[0028] The piston structure 2 further includes a piston pin 6 disposed in the piston head 4, the piston pin 6 being connected to the crankshaft of the compressor via a connecting rod, a pin hole 7 being disposed in the piston head 4, the pin hole 7 being located in the radial direction of the piston head 4, and chamfers being disposed at both ends of the pin hole 7. The piston pin 6 is installed in the pin hole 7, and the piston head 4 is further provided with a pin hole annular groove 8 surrounding the piston head 4 in the circumferential direction. The pin hole annular groove 8 can realize lubrication at the position of the pin hole 7.

[0029] The piston head 4 is provided with an opening on the side facing the connecting rod. After one end of the connecting rod is inserted into the opening, the piston pin 6 is inserted from the pin hole 7 and passes through the hole at the end of the connecting rod that is adapted to the piston pin 6, thereby realizing the connection between the piston head 4 and the connecting rod.

[0030] The crankshaft structure 1 includes a crankshaft, on which a crankpin is provided, and both ends of the connecting rod are rotatably connected to the piston pin 6 and the crankpin, respectively. The crankpin is eccentrically arranged relative to the rotating shaft of the crankshaft, and when the crankshaft rotates, the crankpin also moves along an annular track, thereby moving with it through one end of the connecting rod. Since the piston head 4 is limited by the cylinder hole, the connecting rod can only drive the piston head 4 to reciprocate in the axial direction of the cylinder hole through the piston pin 6.

[0031] The crankshaft is installed in the crankcase and can rotate in the crankcase. An oil storage portion 9 is provided at the bottom of the crankcase. At the same time, an oiling structure is provided on the crankshaft. The oiling structure includes a spiral groove arranged on the crankshaft. When the crankshaft rotates, the oil in the oil storage portion 9 can be transferred to the crankshaft through the spiral groove for lubrication, thereby further reducing the overall friction loss of the compressor.

[0032] Through the improvements of the present application, the overall consumption of the compressor due to friction during use is greatly reduced, which not only saves energy consumption under the same output power, but also increases the maximum output power and has better performance.

[0033] Embodiment 2, as Figure 4 As shown, a piston structure 2 for a refrigeration compressor is used in a refrigerator refrigeration compressor. The compressor includes a crankshaft structure 1, a piston structure 2, and a connecting rod transmission structure 3 connecting the two. The connecting rod transmission structure 3 includes a connecting rod.

[0034] The piston structure 2 includes a piston head 4 installed in the cylinder hole of the compressor. The piston head 4 is roughly cylindrical in shape, with chamfers at both ends and is arranged coaxially with the cylinder hole. The cylinder hole is provided with a limiting surface on the side facing the crankshaft structure 1, so as to limit the piston head 4 and prevent it from escaping from the cylinder hole. The piston head 4 is provided with a friction pair on the outer surface of the part far from the connecting rod, and the friction pair is provided with a lubrication structure 5. By setting the tolerance of the piston head 4 at different positions in the axial direction, when the piston head 4 moves back and forth in the cylinder hole, the friction force is mainly concentrated at the position where the friction pair is located.

[0035] The lubricating structure 5 is evenly distributed in the circumferential direction of the piston head 4. Specifically, the lubricating structure 5 is a plurality of strip grooves, the length direction of which is parallel to the axial direction of the piston head 4. There is no depression in the portion between two adjacent strip grooves, forming a new friction pair. A cavity that can accommodate oil is formed in the strip groove. It produces two effects. First, a small amount of local oil storage can be achieved through the cavity formed at the depression, thereby increasing the lubrication effect between the piston head 4 and the cylinder hole; second, the depression structure reduces the contact area between the piston head 4 and the cylinder hole, further reducing the energy consumed by friction. The circumferentially evenly distributed form allows each position of the piston head 4 in the circumferential direction to be fully lubricated. On the one hand, it can improve the lubrication effect, and on the other hand, it can also prevent the piston head 4 from generating torque due to uneven force at various locations in the circumferential direction.

[0036] The piston structure 2 further includes a piston pin 6 disposed in the piston head 4, the piston pin 6 being connected to the crankshaft of the compressor via a connecting rod, a pin hole 7 being disposed in the piston head 4, the pin hole 7 being located in the radial direction of the piston head 4, and chamfers being disposed at both ends of the pin hole 7. The piston pin 6 is installed in the pin hole 7, and the piston head 4 is further provided with a pin hole annular groove 8 surrounding the piston head 4 in the circumferential direction. The pin hole annular groove 8 can realize lubrication at the position of the pin hole 7.

[0037] The piston head 4 is provided with an opening on the side facing the connecting rod. After one end of the connecting rod is inserted into the opening, the piston pin 6 is inserted from the pin hole 7 and passes through the hole at the end of the connecting rod that is adapted to the piston pin 6, thereby realizing the connection between the piston head 4 and the connecting rod.

[0038] The crankshaft structure 1 includes a crankshaft, on which a crankpin is provided, and both ends of the connecting rod are rotatably connected to the piston pin 6 and the crankpin, respectively. The crankpin is eccentrically arranged relative to the rotating shaft of the crankshaft, and when the crankshaft rotates, the crankpin also moves along an annular track, thereby moving along with it through one end of the connecting rod. Since the piston head 4 is limited by the cylinder hole, the connecting rod can only drive the piston head 4 to reciprocate in the axial direction of the cylinder hole.

[0039] The crankshaft is installed in the crankcase and can rotate in the crankcase. An oil storage portion 9 is provided at the bottom of the crankcase. At the same time, an oiling structure is provided on the crankshaft. The oiling structure includes a spiral groove arranged on the crankshaft. When the crankshaft rotates, the oil in the oil storage portion 9 can be transferred to the crankshaft through the spiral groove for lubrication, thereby further reducing the overall friction loss of the compressor.

[0040] Through the improvements of the present application, the overall consumption of the compressor due to friction during use is greatly reduced, which not only saves energy consumption under the same output power, but also increases the maximum output power and has better performance.

[0041] Embodiment three, as Figure 5 As shown, a piston structure 2 for a refrigeration compressor is used in a refrigerator refrigeration compressor. The compressor includes a crankshaft structure 1, a piston structure 2, and a connecting rod transmission structure 3 connecting the two. The connecting rod transmission structure 3 includes a connecting rod.

[0042] The piston structure 2 includes a piston head 4 installed in the cylinder hole of the compressor. The piston head 4 is roughly cylindrical in shape, with chamfers at both ends and is arranged coaxially with the cylinder hole. The cylinder hole is provided with a limiting surface on the side facing the crankshaft structure 1, so as to limit the piston head 4 and prevent it from escaping from the cylinder hole. The piston head 4 is provided with a friction pair on the outer surface of the part far from the connecting rod, and the friction pair is provided with a lubrication structure 5. By setting the tolerance of the piston head 4 at different positions in the axial direction, when the piston head 4 moves back and forth in the cylinder hole, the friction force is mainly concentrated at the position where the friction pair is located.

[0043] The lubricating structure 5 is an annular groove surrounding the piston head 4 in the circumferential direction. There are several annular grooves, which are spaced apart in the axial direction of the piston head 4. There is no depression between two adjacent annular grooves, forming a new friction pair. A cavity that can accommodate oil is formed in the annular groove. It produces two effects. First, through the cavity formed at the depression, a small amount of local oil storage can be achieved, increasing the lubrication effect between the piston head 4 and the cylinder hole; second, the depression structure reduces the contact area between the piston head 4 and the cylinder hole, further reducing the energy consumed by friction. The circumferentially surrounding structure can make all positions in the circumferential direction of the piston head 4 fully lubricated. On the one hand, since the oil can move in the circumferential direction, the situation of local lack of oil can be avoided, and the lubrication effect can be improved. On the other hand, it also avoids the torque generated by the piston head 4 due to uneven force at various places in the circumferential direction. Further, in this embodiment, the specific number of annular grooves is six. In actual production, the specific number can be adaptively adjusted according to the size of the piston head 4.

[0044] The piston structure 2 further includes a piston pin 6 disposed in the piston head 4, the piston pin 6 being connected to the crankshaft of the compressor via a connecting rod, a pin hole 7 being disposed in the piston head 4, the pin hole 7 being located in the radial direction of the piston head 4, and chamfers being disposed at both ends of the pin hole 7. The piston pin 6 is installed in the pin hole 7, and the piston head 4 is further provided with a pin hole annular groove 8 surrounding the piston head 4 in the circumferential direction. The pin hole annular groove 8 can realize lubrication at the position of the pin hole 7.

[0045] The piston head 4 is provided with an opening on the side facing the connecting rod. After one end of the connecting rod is inserted into the opening, the piston pin 6 is inserted from the pin hole 7 and passes through the hole at the end of the connecting rod that is adapted to the piston pin 6, thereby realizing the connection between the piston head 4 and the connecting rod.

[0046] The crankshaft structure 1 includes a crankshaft, on which a crankpin is provided, and both ends of the connecting rod are rotatably connected to the piston pin 6 and the crankpin, respectively. The crankpin is eccentrically arranged relative to the rotating shaft of the crankshaft, and when the crankshaft rotates, the crankpin also moves along an annular track, thereby moving along with it through one end of the connecting rod. Since the piston head 4 is limited by the cylinder hole, the connecting rod can only drive the piston head 4 to reciprocate in the axial direction of the cylinder hole.

[0047] The crankshaft is installed in the crankcase and can rotate in the crankcase. An oil storage portion 9 is provided at the bottom of the crankcase. At the same time, an oiling structure is provided on the crankshaft. The oiling structure includes a spiral groove arranged on the crankshaft. When the crankshaft rotates, the oil in the oil storage portion 9 can be transferred to the crankshaft through the spiral groove for lubrication, thereby further reducing the overall friction loss of the compressor.

[0048] Through the improvements of the present application, the overall consumption of the compressor due to friction during use is greatly reduced, which not only saves energy consumption under the same output power, but also increases the maximum output power and has better performance.

Claims

1. A piston structure for a refrigeration compressor, characterized in that: It includes a piston head installed in a cylinder hole, wherein a friction pair is provided on the piston head, and a lubrication structure is provided at the friction pair, wherein the lubrication structure is a recessed structure arranged on the surface of the piston head; the lubrication structure is a plurality of circular pits, or the lubrication structure is a plurality of strip grooves, and the length direction of the strip grooves is parallel to the axial direction of the piston head.

2. A piston structure for a refrigeration compressor according to claim 1, characterized in that: The lubrication structures are evenly distributed in the circumferential direction of the piston head.

3. A piston structure for a refrigeration compressor according to claim 1, characterized in that: The lubricating structure is an annular groove surrounding the piston head in the circumferential direction.

4. A piston structure for a refrigeration compressor according to claim 3, characterized in that: There are several annular grooves, which are distributed at intervals in the axial direction of the piston head.

5. A piston structure for a refrigeration compressor according to any one of claims 1 to 3, characterized in that: A piston pin is arranged in the piston head, and the piston pin is connected to the crankshaft of the compressor through a connecting rod.

6. A piston structure for a refrigeration compressor according to claim 5, characterized in that: A pin hole is provided in the piston head, the pin hole is located in the radial direction of the piston head, and the piston pin is installed in the pin hole.

7. A piston structure for a refrigeration compressor according to claim 6, characterized in that: The piston head is also provided with a pin hole annular groove which surrounds the piston head in the circumferential direction.

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