[0024] A preferred embodiment is given below to illustrate the present invention more clearly and completely in conjunction with the accompanying drawings.
[0025] Such as Figure 1-Figure 3 As shown, the present invention includes an air source heat pump system, including a compressor 1, a fin heat exchanger 4, a shell and tube heat exchanger 5, and a gas-liquid separator 2 connected to the compressor 1, and is characterized in that the shell and tube The heat exchanger 5 includes a gas pipe 53, a liquid pipe 54, a heat exchange pipe 58, and a liquid separation device. The air source heat pump system also includes a four-way valve 3, which is connected to the compressor 1, the gas-liquid separator 2, and the fin respectively. The fin heat exchanger 4 and the air pipe 53 are connected, among which,
[0026] Such as figure 1 As shown, the fin heat exchanger 4 communicates with the liquid pipe 54 through the orifice plate 8 and the first one-way valve 71; meanwhile, the fin heat exchanger 4 communicates with the liquid pipe 54 through the expansion valve 6 and the second one-way valve 72 ;
[0027] The first one-way valve 71 is used for one-way conduction from the fin heat exchanger 4 to the liquid separating device;
[0028] The second one-way valve 72 is used for one-way conduction of the liquid pipe 54 to the fin heat exchanger 4.
[0029] The four-way valve 3 switches the flow direction of the gas refrigerant, and can be controlled by the controller to complete the switching of cooling, heating, and defrosting modes.
[0030] In this solution, the shell and tube heat exchanger 5 doubles as a heat exchanger in the cooling and heating mode, liquid refrigerant in the storage system, and gas-liquid separator 2 in the cooling mode, so the system does not need to add a liquid refrigerant accumulator, thereby saving costs ; At the end of defrosting, there will not be a large amount of liquid refrigerant flowing back to compressor 1; in the cooling mode, the refrigerant does not need to be superheated in the shell side, which improves the suction pressure and the operating efficiency of the cooling mode; the overall system uses fewer valves and has high reliability .
[0031] Such as figure 2 with image 3 As shown, the shell and tube heat exchanger 5 further includes a water outlet 57 and a water inlet 56. The liquid separation device is located above the heat exchange tube 58. The liquid separation device includes a spray tube 51 and a liquid separation plate 52. The shower pipe 51 is installed above the liquid separating tray 52.
[0032] The expansion valve 6 in this embodiment is an electronic expansion valve or a thermal expansion valve. The heat exchange tube 58 is a copper tube.
[0033] The throttling device is the orifice plate 8. As a throttling device, the orifice plate 8 has the advantage of low cost. The orifice plate 8 guarantees the normal working condition, the liquid refrigerant can pass through or a small amount of gas is passed, and the refrigerant does not accumulate in the fin heat exchanger 4, and becomes a gas-liquid two-phase refrigerant after throttling.
[0034] Such as figure 2 As shown, the shell and tube heat exchanger 5 includes a liquid injection pipe 55, and the liquid injection pipe 55 communicates with the compressor 1 through a liquid injection solenoid valve 9. The liquid injection solenoid valve 9 is used to reduce the temperature of the compressor 1 motor when the motor temperature is high; during the cooling mode and defrosting process, the lubricating oil thrown out with the compressor 1 exhaust gas accumulates in the shell and tube heat exchanger 5, and the running time is interrupted. Open, used to recover compressor 1 lubricant.
[0035] The air source heat pump system has three operating modes, listed as follows:
[0036] 1. Heating mode:
[0037] 1. The exhaust of compressor 1 enters the shell side of the shell and tube heat exchanger 5 through the four-way valve 3, and after heat exchange with the user's hot water, it becomes a high-pressure liquid refrigerant;
[0038] 2. After the high-pressure refrigerant passes through the one-way valve, the expansion valve 6 adjusts the valve opening to chase the superheat of the intake air, and it becomes a gas-liquid two-phase refrigerant after throttling;
[0039] 3. The gas-liquid two-phase refrigerant absorbs heat from the environment into gaseous refrigerant in the fin heat exchanger 4 tube, enters the gas-liquid separator 2 through the four-way valve 3, and finally enters the compressor 1 to suck in air to complete heating A cycle of patterns.
[0040] 2. Cooling mode:
[0041] 1. The exhaust of compressor 1 enters the 4 tubes of the fin heat exchanger through the four-way valve 3, and after heat exchange with ambient air, it becomes a high-pressure liquid refrigerant;
[0042] 2. Due to the existence of the one-way valve, the liquid refrigerant can only go through the orifice plate 8. The orifice plate 8 is designed to ensure normal working conditions. The liquid refrigerant can pass through or a small amount of gas can be used to ensure that the refrigerant does not accumulate on the fins. In the heat exchanger 4, it becomes a gas-liquid two-phase refrigerant after throttling;
[0043] 3. The gas-liquid two-phase refrigerant passes through the liquid separation device of the shell and tube heat exchanger 5, and drops uniformly from the shell side to the heat exchange tube 58 of the shell and tube heat exchanger 5, and changes heat from the frozen water required by the user to a gas state The refrigerant enters the gas-liquid separator 2 through the four-way valve 3, and finally enters the compressor 1 for suction, completing a cycle of the refrigeration mode.
[0044] 3. Defrost mode:
[0045] 1. When the controller detects that the system suction saturation temperature is ≤a*ambient temperature+b, the four-way valve 3 is switched, and the system enters the defrost mode;
[0046] 2. Before defrosting: Compressor 1 exhaust is connected to the shell tube, and the air intake is connected to the fin; during defrosting: the air intake is connected to the shell tube, and the compressor 1 exhaust is connected to the fin; after exiting defrosting: The exhaust of the compressor 1 is connected to the shell tube, and the gas inlet is connected to the fins.
[0047] 3. During the defrosting process, the exhaust from compressor 1 enters the fin heat exchanger 4 through the four-way valve 3 and exchanges heat with the fins. The fins are frosted and become liquid water and drained, and the refrigerant changes from high-pressure gas. High pressure liquid refrigerant;
[0048] 4. During the defrosting process, due to the existence of the one-way valve, the liquid refrigerant can only pass through the orifice plate 8. The orifice plate 8 is designed to ensure normal working conditions. The liquid refrigerant can pass through or a small amount of gas can flow to ensure that the refrigerant is not Accumulate in the fin heat exchanger 4 and become a gas-liquid two-phase refrigerant after throttling;
[0049] 5. During the defrosting process, the gas-liquid two-phase refrigerant passes through the liquid separating device of the shell and tube heat exchanger 5, and drops uniformly from the shell side to the heat exchange tube 58 of the shell and tube heat exchanger 5. The heat absorption becomes a gaseous refrigerant, enters the gas-liquid separator 2 through the four-way valve 3, and finally enters the compressor 1 for suction, completing a cycle of the heating mode.
[0050] Although the specific embodiments of the present invention are described above, those skilled in the art should understand that these are only examples, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these implementations without departing from the principle and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.
