Electronic expansion valve

Abstract

The invention relates to the technical field of control valves, and discloses an electronic expansion valve which comprises a drive part and a valve body part. The valve body part comprises a valve body with a flow path inlet and a flow path outlet, a valve core placed in an inner cavity of the valve body, and a valve core seat with a valve opening part. The electronic expansion valve is characterized in that the valve core comprises a body section and an adjusting section facing the valve core seat, the body section and the adjusting section are connected through a conical opening section, the adjusting section comprises at least one first circular arc section for adjusting a refrigerating fluid flow curve, the valve core seat comprises a valve opening part which is in a straight section and the conical opening section which is formed by extending from the valve opening part to the valve core, the diameter of the valve opening part is defined as phi 2, the diameter of the small end of a conical transitional section of the valve core is defined as phi 3, the diameter of the big end of the conical transitional section of the valve core is defined as phi 5, and the relation requirement of phi 3<phi 2<phi 5 is met. The electronic expansion valve facilitates adjustment of an air-conditioning system, reduces adjusting frequency, and improves the stability of the system.

Description

technical field [0001] The invention relates to the technical field of control valves, in particular to an electronic expansion valve for regulating refrigerant flow. Background technique [0002] In various refrigeration / heating equipment such as air conditioners, refrigerators, heat pump water heaters, etc., electronic expansion valves are usually used to regulate the flow of fluids. [0003] The electronic expansion valve usually includes two parts: a motor (driver part) with a stepping motor and a valve body part as an actuator part. The valve body part includes a valve body with a refrigerant flow path inlet and a flow path outlet. The spool in the inner cavity and the spool seat with the valve port part drive the axial movement of the spool relative to the valve port part by inputting pulse signals to the motor of the driving part to change the refrigerant flow through the valve port part. The flow rate is to adjust the refrigerant flow at the outlet of the flow path ...

AI Technical Summary

Problems solved by technology

However, although the above technology can improve the accuracy of the electronic expansion valve at a small opening to a certain extent, due to the sudden change point in the entire flow curve and the influence of manufacturing errors, the position of P3' fluctuates greatly, generally 40 - The difference of 60 pulses will cause a difference of at least 40 pulses at P2' point, resulting in unpredictable flow before and after P2' point, thus reducing the adjustment accuracy of the whole curve

At the same time, although the flow change law before P2' is consistent with (Q2'-Q1') / (P2'-P1')=K, and K is approximately a constant value, it is still very difficult to know how to change the increase ratio of a pulse flow , which will increase the number of expansion valve adjustments, affect the stability of the air conditioning system, and also cause a decrease in the energy efficiency ratio

Host manufacturers will also rely too much on the accuracy of fixed-point flow control, resulting in a lot of unnecessary control waste

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