Thermal expansion valve and air conditioning apparatus using the same

Abstract

A thermal expansion valve for automotive coolant systems which is significantly more compact than previously developed expansion values. The housing of the expansion valve is divided into a first housing formed in a cylindrical shape with a bottom and a second housing formed in a columnar shape. The first housing is fit into the second housing, and both are integrally connected to each other. A temperature sensing mechanism having a temperature sensing chamber and an expansion mechanism for adjusting an opening degree of a throttle passage in accordance with an evaporator outlet temperature sensed by the temperature sensing means are disposed in the second housing. First and fourth joint portions connected to inlet and outlet refrigerant pipes of the evaporator, respectively, are at the bottom of the first housing. On the other hand, second and third joint portions connected to a compressor suction side refrigerant pipe and a high-pressure side refrigerant pipe from a receiver, respectively, are at an outer surface of the second housing. In this manner the overall size of the expansion valve is reduced considerably, thus saving valuable space in an engine compartment of a vehicle.