R290 refrigerant air conditioning system thermal expansion valve

Abstract

The invention discloses a thermal expansion valve for an R290 refrigerant air-conditioning system, which includes a temperature bulb, an air box head, and a valve body. The valve body is connected with an inlet connecting pipe, an outlet connecting pipe and an external balance connecting pipe. The temperature bulb communicates with the air box head through a capillary tube. The temperature bulb is filled with a temperature-sensing working medium, which is a mixed gas different from the working medium of the air-conditioning system. In the range of cooling and heating conditions, the deviation of superheat is less than 0.9°C, so that when the thermal expansion valve operates in cooling and heating conditions, the control of the superheat of the evaporator is more consistent, ensuring the stability and comfort of the air conditioning system. sex.

Description

【Technical field】 [0001] The invention relates to a throttling element in the field of air conditioning, in particular to a thermal expansion valve for an R290 new refrigerant air conditioner. 【Background technique】 [0002] Because the refrigerant R22 widely used by air-conditioning companies not only has a strong destructive effect on the ozone layer, but also belongs to greenhouse gases, and belongs to the refrigerant that needs to be phased out as agreed in the "Montreal Protocol" (developed countries will completely ban the use of R22 refrigeration in 2020. Developing countries are scheduled to completely stop using R22 refrigerant in 2030); and R410a refrigerant is currently a popular transitional alternative refrigerant. Although it will not destroy the ozone layer, it is still a greenhouse gas that needs to be reduced and will face secondary disuse. Countries all over the world are eager to find more ideal and truly environmentally friendly refrigerant substitutes. ...

AI Technical Summary

Problems solved by technology

For the charging problem of the temperature bulb medium of the thermal expansion valve, the solution generally adopted in the industry is the same working substance charging, that is, the working fluid in the temperature bulb and the air conditioning system are the same refrigerant, and this charging method is only suitable for relatively The range of working conditions is small, but if the range of working conditions is wide, especially at low temperature conditions, the thermal expansion valve filled with the same working fluid will show a very large superheat control deviation, generally above 2°C, making The consistency of superheat control under different working conditions is poor, which affects the stability of air conditioning system operation and system energy efficiency

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