Pump body assembly, variable displacement compressor and air conditioning system

Abstract

The application provides a pump body assembly, a variable displacement compressor and an air conditioning system. The pump body assembly comprises at least two cylinders and a variable displacement tank (10), at least one of the at least two cylinders is a variable displacement cylinder, the variable displacement cylinder is provided with a variable displacement vane, the tail of the variable displacement vane is provided with a pneumatic drive cavity (302), the pneumatic drive cavity (302) is communicated with the variable displacement tank (10) through a ventilation flow path (301), the maximum volume of the pneumatic drive cavity (302) is V1, the minimum value of the effective flow area of the ventilation flow path (301) is S, and the relationship between S and V1 satisfies S / V1≥0.02. According to the pump body assembly, the problem of liquid refrigerant accumulation at the tail of the vane of the pump body assembly and the problem of large pressure pulsation at the tail of the vane can be effectively solved, abnormal noise of the compressor is avoided, and user experience is improved.

Description

Technical Field

[0001] This application relates to the field of compressor technology, specifically to a pump assembly, a variable capacity compressor, and an air conditioning system. Background Technology

[0002] To simultaneously meet the energy efficiency requirements of multi-split air conditioning systems under both low and high loads, variable displacement compressors are increasingly being used in these systems. Existing variable displacement compressors generally employ a vane tail-sealing structure, allowing high or low pressure to be applied to activate or deactivate the variable displacement cylinder. Related technologies disclose a variable displacement mechanism where the tail of the variable displacement cylinder vane can selectively connect to either the compressor's suction or exhaust pipe. Specifically, the pin head can be supplied with either high or low pressure, while the pin tail remains connected to the compressor's suction pipe at a low pressure. The pressure difference between the pin head and tail allows for locking or disengagement of the pin and vane, thus enabling switching between single and dual cylinder operation.

[0003] The problem is that when the system is heating at low temperatures, the outdoor temperature is low, causing the compressor suction superheat to be less than 0, and the compressor suction carries some liquid refrigerant. Some liquid refrigerant also accumulates at the tail of the variable displacement cylinder vane. When the compressor switches from single-cylinder to dual-cylinder operation, the liquid refrigerant at the tail of the variable displacement cylinder vane cannot be discharged in time, resulting in large pressure pulsations at the tail of the vane and abnormal noise from the compressor, which seriously affects the user experience. Summary of the Invention

[0004] Therefore, the technical problem to be solved by this application is to provide a pump body assembly, a variable capacity compressor and an air conditioning system, which can effectively solve the problems of liquid refrigerant accumulation at the tail of the pump body assembly vane and large pressure pulsation at the tail of the vane, avoid abnormal noise from the compressor and improve the user experience.

[0005] To address the aforementioned issues, this application provides a pump body assembly comprising at least two cylinders and a variable displacement tank. At least one of the cylinders is a variable displacement cylinder, which is provided with a variable displacement vane. The tail of the variable displacement vane is provided with a pneumatic drive chamber, which is connected to the variable displacement tank via an airflow path. The maximum volume of the pneumatic drive chamber is V1, and the minimum effective flow area of ​​the airflow path is S, wherein the relationship between S and V1 satisfies S / V1≥0.02.

[0006] Preferably, the effective volume of the variable displacement tank is V2, and the relationship between V1 and V2 satisfies V2 / V1≥20.

[0007] Preferably, the airflow path includes a variable displacement vent, which is connected to the variable displacement tank via a connecting pipe.

[0008] Preferably, the airflow path further includes a first channel and a second channel spaced apart. The first channel is located above the variable-capacity vent, and the second channel is located below the variable-capacity vent. The variable-capacity vent is connected to the variable-capacity vent through the first channel and the second channel.

[0009] Preferably, the height of the variable displacement cylinder is H, and the sum of the heights of the first channel and the second channel is h, where H / 4 ≤ h ≤ H / 2.

[0010] Preferably, the first channel and the second channel have the same height.

[0011] Preferably, the pump body assembly further includes a pin and a pin spring. The variable displacement slide is provided with a locking groove on the side facing the pin. The pin can extend into the locking groove under the action of the pin spring to unload the variable displacement cylinder, or disengage from the locking groove under the variable displacement pressure of the variable displacement tank to enable the variable displacement cylinder to work.

[0012] According to another aspect of this application, a variable displacement compressor is provided, including a pump body assembly, which is the pump body assembly described above.

[0013] According to another aspect of this application, an air conditioning system is provided, including a variable capacity compressor, which is the variable capacity compressor described above.

[0014] Preferably, the air conditioning system further includes a condenser, a throttling device, and an evaporator. The evaporator is connected to the suction pipe of the compressor, the condenser is connected to the discharge pipe of the compressor, and the variable displacement tank is connected to the discharge pipe through a first branch and to the suction pipe through a second branch. A first control valve for controlling the opening and closing of the first branch is provided on the first branch, and a second control valve for controlling the opening and closing of the second branch is provided on the second branch.

[0015] The pump assembly provided in this application includes at least two cylinders and a variable displacement tank. At least one of the cylinders is a variable displacement cylinder, and a variable displacement vane is provided on the variable displacement cylinder. A pneumatic drive chamber is provided at the tail end of the variable displacement vane. The pneumatic drive chamber is connected to the variable displacement tank via an air passage. The maximum volume of the pneumatic drive chamber is V1, and the minimum effective flow area of ​​the air passage is S, where the relationship between S and V1 satisfies S / V1≥0.02. This pump assembly defines the proportional relationship between the flow area of ​​the air passage between the pneumatic drive chamber and the variable displacement tank and the maximum volume of the pneumatic drive chamber. This ensures that the flow area of ​​the air passage is related to the maximum volume of the pneumatic drive chamber, thereby increasing the effective area of ​​the air passage. This effectively solves the problems of liquid refrigerant accumulation at the tail end of the variable displacement cylinder vane and large pressure pulsation at the tail end of the vane, avoids abnormal noise from the compressor, and improves the user experience. Attached Figure Description

[0016] Figure 1This is a schematic diagram of the structure of an air conditioning system according to an embodiment of this application;

[0017] Figure 2 This is a schematic diagram of the structure of a pump body assembly according to an embodiment of this application;

[0018] Figure 3 This is an exploded structural diagram of a pump body assembly according to an embodiment of this application;

[0019] Figure 4 and Figure 5 This is a schematic diagram illustrating the pressure pulsation generation principle of a variable displacement compressor according to an embodiment of this application;

[0020] Figure 6 This is a graph showing the relationship between crankshaft rotation angle and pressure in a variable displacement compressor according to an embodiment of this application.

[0021] Figure 7 This is a graph showing the relationship between S / V1 and pressure pulsation for a variable displacement compressor according to an embodiment of this application.

[0022] Figure 8 This is a diagram showing the relationship between V2 / V1 and ΔP2 / ΔP1 for a variable displacement compressor according to an embodiment of this application.

[0023] Figure 9 This is an exploded view of the assembly structure of a pump body assembly according to an embodiment of this application;

[0024] Figure 10 This is a cross-sectional view of the pneumatic drive chamber of a pump body assembly according to an embodiment of this application.

[0025] The reference numerals in the attached figures are as follows:

[0026] 1. Compressor; 2. Condenser; 3. Throttling device; 4. Evaporator; 5. First control valve; 6. Second control valve; 7. Exhaust pipe; 8. Suction pipe; 9. Connecting pipe; 10. Variable displacement tank; 201. Crankshaft; 202. Upper flange; 203. Upper cylinder; 204. Upper spring; 205. Upper roller; 206. Upper vane; 207. Partition plate; 208. Lower cylinder; 209. Lower roller; 210. Lower vane; 211. Lower flange; 212. Pin; 213. Pin spring; 214. Lower cover plate; 301. Air passage; 302. Pneumatic drive chamber; 303. Variable displacement vent; 304. First channel; 305. Second channel. Detailed Implementation

[0027] See also Figures 1 to 10As shown, according to an embodiment of this application, the pump body assembly includes at least two cylinders and a variable displacement tank 10. At least one of the at least two cylinders is a variable displacement cylinder. A variable displacement vane is provided on the variable displacement cylinder. A pneumatic drive chamber 302 is provided at the tail of the variable displacement vane. The pneumatic drive chamber 302 is connected to the variable displacement tank 10 via a flow passage 301. The maximum volume of the pneumatic drive chamber 302 is V1. The minimum effective flow area of ​​the flow passage 301 is S. The relationship between S and V1 satisfies S / V1≥0.02.

[0028] The pump assembly defines the proportional relationship between the flow area of ​​the air passage 301 between the pneumatic drive chamber 302 and the variable displacement tank 10 and the maximum volume of the pneumatic drive chamber 302. This allows the flow area of ​​the air passage 301 to be related to the maximum volume of the pneumatic drive chamber 302, thereby increasing the effective area of ​​the air passage 301. This effectively solves the problems of liquid refrigerant accumulation at the tail of the variable displacement cylinder vane and large pressure pulsation at the tail of the vane, avoids abnormal noise from the compressor, and improves the user experience.

[0029] Specifically, the pump body assembly includes a crankshaft 201, an upper flange 202, an upper cylinder 203, an upper spring 204, an upper roller 205, an upper vane 206, a partition 207, a lower cylinder 208, a lower roller 209, a lower vane 210, a lower flange 211, a pin 212, a pin spring 213, and a lower cover plate 214.

[0030] The lower cylinder 208 is a variable displacement cylinder. The tail of the upper vane 206 is an open structure, meaning it is directly connected to the high pressure inside the compressor. The tail of the upper vane 206 is connected to the upper spring 204, thus the upper cylinder 203 is always in operation. The tail of the lower vane 210 is a sealed pneumatic drive chamber 302. The pneumatic drive chamber 302 is connected to the variable displacement tank 10 via the connecting pipe 9, introducing either the high or low pressure from the variable displacement tank 10 into the tail of the lower vane 210. Therefore, the pneumatic drive chamber 302, i.e., the head of the pin 212, can switch between high and low pressure; simultaneously, the tail of the pin 212 always maintains low pressure. When the pneumatic drive chamber 302 is under high pressure, the pressure overcomes the spring force of the pin spring 213, causing the pin 212 to retract completely into the pin hole, and the lower cylinder 208 is in the working state; when the pneumatic drive chamber 302 is under low pressure, the head and tail of the pin 212 are subjected to the same pressure, and it is subjected to the spring force of the pin spring 213, causing the pin 212 to extend and lock the sliding plate 210, and the lower cylinder 208 is in the unloading state.

[0031] The problem with this pump assembly is that when the system is heating at low temperatures, the compressor suction superheat is less than 0 due to the low outdoor temperature, causing the compressor suction to carry some liquid refrigerant. Some liquid refrigerant also accumulates in the pneumatic drive chamber 302, the air passage 301, and the variable displacement tank 10 at the tail of the sliding vane 210. When the compressor switches from single-cylinder to dual-cylinder operation, the liquid refrigerant in the pneumatic drive chamber 302, the air passage 301, and the variable displacement tank 10 cannot be discharged in time. Simultaneously, the sliding vane 210 reciprocates with the lower roller 209, causing significant pressure pulsations in the pneumatic drive chamber 302. Figure 6 The figure shows the pressure change curve in the pneumatic drive chamber 302. When the pressure fluctuation in the pneumatic drive chamber 302 is large, the force on the tail of the sliding vane 210 changes significantly. Since there is no spring structure at the tail of the sliding vane 210, the sliding vane 210 separates from the lower roller 209 and impacts it, causing abnormal noise in the compressor, which seriously affects the user experience.

[0032] Experimental studies have shown that the ratio of the minimum effective flow area S of the airflow path 301 to the maximum volume V1 of the pneumatic drive cavity 302 is closely related to the pressure pulsation amplitude within the pneumatic drive cavity 302. For example... Figure 7 The diagram shows the relationship between the pressure pulsation amplitude ΔP and S / V1. When the value of S / V1 increases, the pressure pulsation amplitude decreases significantly, and when the value of S / V1 is greater than or equal to 0.02, the change in pressure pulsation amplitude is very small. Therefore, in order to minimize the pressure pulsation in the pneumatic drive cavity 401 and ensure that the lower slide plate 210 and the lower roller 209 do not detach, S and V1 should satisfy: S / V1 ≥ 0.02.

[0033] Furthermore, pressure pulsations in the pneumatic drive chamber 302 are directly transmitted to the first control valve 5 or the second control valve 6 via the variable capacity tank 10. During heating operation, the variable capacity tank 10 is connected to the condenser 2 via the first control valve 5; therefore, pressure pulsations in the pneumatic drive chamber 302 are directly transmitted to the indoor unit, causing abnormal noise.

[0034] To address this issue, in one embodiment, the effective volume of the variable volume tank 10 is V2, and the relationship between V1 and V2 satisfies V2 / V1≥20.

[0035] The effective volume of the variable displacement tank 10 is V2, and the pressure pulsation amplitudes before and after the variable displacement tank 10 are ΔP1 and ΔP2, respectively. For example... Figure 8 As shown, increasing the value of V2 / V1 can significantly reduce the value of ΔP2 / ΔP1, thus weakening pressure pulsation. To minimize the value of ΔP2 and ensure that the indoor unit does not produce abnormal noise under heating conditions, V1 and V2 should satisfy: V2 / V1≥20.

[0036] In one embodiment, the air passage 301 includes a variable displacement vent 303, which is connected to the variable displacement tank 10 via a connecting pipe 9. In this embodiment, the variable displacement vent 303 is disposed on the variable displacement cylinder and extends to the outer peripheral wall of the cylinder. One end of the connecting pipe 9 is connected to the variable displacement vent 303, and the other end extends out of the variable displacement compressor and is connected to the variable displacement tank 10 located outside the compressor.

[0037] In one embodiment, the airflow path 301 further includes a first channel 304 and a second channel 305 spaced apart. The first channel 304 is located above the variable capacity vent 303, and the second channel 305 is located below the variable capacity vent 303. The variable capacity vent 303 is connected to the variable capacity vent 303 via the first channel 304 and the second channel 305. In this embodiment, by providing the first channel 304 and the second channel 305 on the upper and lower sides of the variable capacity vent 303, and ensuring that the refrigerant entering through the variable capacity vent 303 does not directly enter the pneumatic drive chamber 302, but instead enters the pneumatic drive chamber 302 via the first channel 304 and the second channel 305, it is possible to prevent the refrigerant in the variable capacity vent 303 from directly impacting the variable capacity slide plate in the pneumatic drive chamber 302, thereby reducing the fluctuation of the variable capacity slide plate and improving the stability of the variable capacity slide plate during operation. The refrigerant in the variable displacement vent 303 enters the pneumatic drive chamber 302 simultaneously through the channels on both the upper and lower sides. This allows the refrigerant to apply force to both the upper and lower sides of the variable displacement vane at the same time, preventing the variable displacement vane from tilting due to unbalanced force, which could lead to jamming or wear due to skewness.

[0038] In this embodiment, the variable displacement compressor's variable displacement control structure includes a partition 207, a lower cylinder 208, a lower slide vane 210, and a lower flange 211. The lower slide vane 210 has a pneumatic drive chamber 302 at its tail end, and the lower cylinder 208 also has a variable displacement vent 303. A first channel 304 and a second channel 305 are respectively provided between the pneumatic drive chamber 302 and the variable displacement vent 303. The pneumatic drive chamber 302 is connected to the variable displacement vent 303 via the first channel 304 and the second channel 305, and the variable displacement vent 303 is connected to the variable displacement tank 10 via a connecting pipe 9. The airflow path 301 includes the first channel 304, the second channel 305, the variable displacement vent 303, and the connecting pipe 9.

[0039] In one embodiment, the height of the variable displacement cylinder is H, and the sum of the heights of the first channel 304 and the second channel 305 is h, where H / 4 ≤ h ≤ H / 2. In this embodiment, the height of the first channel 304 is h1, and the height of the second channel 305 is h2, where h = h1 + h2. During compressor operation, if h is too large, the variable displacement cylinder will lack strength, its vane groove will deform more, and wear between the two will be aggravated, leading to insufficient compressor reliability.

[0040] In one embodiment, the first channel 304 and the second channel 305 are at the same height, which can further improve the consistency of air intake on both the upper and lower sides and improve the stability of the variable displacement slide force structure.

[0041] In one embodiment, the pump body assembly further includes a pin 212 and a pin spring 213. The variable displacement slide is provided with a locking groove on the side facing the pin 212. The pin 212 can extend into the locking groove under the action of the pin spring 213 to unload the variable displacement cylinder, or disengage from the locking groove under the variable displacement pressure of the variable displacement tank 10 to make the variable displacement cylinder work.

[0042] According to an embodiment of this application, the variable displacement compressor includes a pump body assembly, which is the pump body assembly described above.

[0043] According to an embodiment of this application, the air conditioning system includes a variable capacity compressor 1, which is the variable capacity compressor described above.

[0044] The air conditioning system also includes a condenser 2, a throttling device 3, and an evaporator 4. The evaporator 4 is connected to the suction pipe 8 of the compressor 1, and the condenser 2 is connected to the discharge pipe 7 of the compressor 1. The variable capacity tank 10 is connected to the discharge pipe 7 through a first branch and to the suction pipe 8 through a second branch. A first control valve 5 is provided on the first branch to control the opening and closing of the first branch, and a second control valve 6 is provided on the second branch to control the opening and closing of the second branch.

[0045] When the first control valve 5 is opened, the second control valve 6 is closed, the variable displacement tank 10 is connected to the exhaust pipe 7, and the variable displacement tank 10 is under high pressure; when the second control valve 6 is opened, the first control valve 5 is closed, the variable displacement tank 10 is connected to the suction pipe 6, and the variable displacement tank 10 is under low pressure, thereby realizing the pressure switching in the pneumatic drive chamber 302, and thus realizing the variable displacement control of the variable displacement compressor 1.

[0046] This embodiment is applicable not only to dual-rotor variable displacement compressors, but also to multi-rotor variable displacement compressors.

[0047] It will be readily understood by those skilled in the art that the aforementioned advantageous methods can be freely combined and superimposed without conflict.

[0048] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application. The above are merely preferred embodiments of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the protection scope of this application.

Claims

1. A pump body assembly, characterized in that, It includes at least two cylinders and a variable displacement tank (10), wherein at least one of the at least two cylinders is a variable displacement cylinder, the variable displacement cylinder is provided with a variable displacement slide, the tail of the variable displacement slide is provided with a pneumatic drive chamber (302), the pneumatic drive chamber (302) is connected to the variable displacement tank (10) through a flow passage (301), the maximum volume of the pneumatic drive chamber (302) is V1, and the minimum effective flow area of ​​the flow passage (301) is S, wherein the relationship between S and V1 satisfies S / V1≥0.02; The air passage (301) includes a variable volume air vent (303), which is connected to the variable volume tank (10) via a connecting pipe (9); The airflow path (301) further includes a first channel (304) and a second channel (305) spaced apart. The first channel (304) is located above the variable capacity vent (303), and the second channel (305) is located below the variable capacity vent (303). The variable capacity vent (303) is connected to the variable capacity vent (303) through the first channel (304) and the second channel (305). The refrigerant at the variable capacity vent (303) enters the pneumatic drive chamber (302) through the first channel (304) and the second channel (305) to avoid the refrigerant directly impacting the variable capacity sliding plate in the pneumatic drive chamber (302).

2. The pump body assembly according to claim 1, characterized in that, The effective volume of the variable volume tank (10) is V2, and the relationship between V1 and V2 satisfies V2 / V1≥20.

3. The pump body assembly according to claim 1, characterized in that, The height of the variable displacement cylinder is H, and the sum of the heights of the first channel (304) and the second channel (305) is h, where H / 4≤h≤H / 2.

4. The pump body assembly according to claim 3, characterized in that, The first channel (304) and the second channel (305) have the same height.

5. The pump body assembly according to claim 1, characterized in that, The pump body assembly also includes a pin (212) and a pin spring (213). The variable displacement slide is provided with a locking groove on the side facing the pin (212). The pin (212) can extend into the locking groove under the action of the pin spring (213) to unload the variable displacement cylinder, or disengage from the locking groove under the variable displacement pressure of the variable displacement tank (10) to make the variable displacement cylinder work.

6. A variable displacement compressor, comprising a pump body assembly, characterized in that, The pump assembly is the pump assembly according to any one of claims 1 to 5.

7. An air conditioning system comprising a variable capacity compressor (1), characterized in that, The variable capacity compressor (1) is the variable capacity compressor as described in claim 6.

8. The air conditioning system according to claim 7, characterized in that, The air conditioning system also includes a condenser (2), a throttling device (3), and an evaporator (4). The evaporator (4) is connected to the suction pipe (8) of the compressor (1), and the condenser (2) is connected to the discharge pipe (7) of the compressor (1). The variable displacement tank (10) is connected to the discharge pipe (7) through a first branch and to the suction pipe (8) through a second branch. A first control valve (5) for controlling the opening and closing of the first branch is provided on the first branch, and a second control valve (6) for controlling the opening and closing of the second branch is provided on the second branch.

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