Thermostatic expansion valve

Abstract

The invention discloses a thermostatic expansion valve, and belongs to the technical field of steam compression type refrigeration. The thermostatic expansion valve is suitable for car air conditioning systems. The thermostatic expansion valve is mainly composed of a heating power head (1), a valve body (2), a valve rod (3), a valve element (4), an adjusting spring (5) and the like. The thermostatic expansion valve is characterized in that a valve seat hole (21) is formed by combining a valve seat conic hole (211) and a valve seat cylindrical hole (212); and the valve element (4) is formed by combining a lower valve element cone (41) and an upper valve element cone (42). The sealing performance of the lower valve element cone (41) and the valve seat cylindrical hole (212) is good, and the liquid hammer phenomenon of a compressor is avoided. A lower valve element cone conic angle (411) is larger than an upper valve element cone conic angle (471), and filth blockage of the thermostatic expansion valve is avoided. The upper valve element cone conic angle (471) is equal to a valve seat conic hole cone angle (2111) in degree so that a system cannot generate fluctuation or vibration. A minimum fixing gap (6) is reserved between the upper valve element cone (42) and the valve seat conic hole (211), and blocking of the thermostatic expansion valve is avoided.

Description

technical field [0001] The invention relates to a thermal expansion valve, which belongs to the technical field of vapor compression refrigeration and is suitable for various thermal expansion valves in automobile air-conditioning systems. Background technique [0002] As a key component in the automotive air-conditioning system, the thermal expansion valve plays the role of throttling and reducing pressure, regulating flow, and maintaining an appropriate degree of superheat. Its performance directly affects the performance of the air-conditioning system. [0003] Automobile air-conditioning system is composed of compressor, condenser, evaporator, thermal expansion valve, liquid storage dryer, etc. There is no gas-liquid separator like household air-conditioning system. In the household air-conditioning system, the gas-liquid separator and the compressor are assembled together, and the return air refrigerant of the system passes through the gas-liquid separator and then ente...

AI Technical Summary

Problems solved by technology

But when the air conditioning system is not working, the valve core 4 and the valve seat hole 21 are in a closed state. Due to machining accuracy and assembly errors, it is difficult to ensure that the valve core 4 and the valve seat hole 21 are in a good sealing state, that is, there is a large valve mouth leak

When the system is just started, if the leakage value of the valve port is large, a large amount of refrigerant liquid will flow into the compressor through the evaporator without being completely evaporated, causing the compressor to produce "liquid hammer", which will damage the compressor and reduce the reliability of the system

The throttling passage area between the valve core 4 and the valve seat hole 21 is small, and the system garbage is easily blocked here, resulting in "dirty blockage" and causing the air conditioning system to fail

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