PURPOSE: To simultaneously fix a pair of cooling medium conduits to component parts of an air conditioner by setting an invasion passage by a holding mechanism to be narrower than a large diameter part of the corresponding cooling medium conduit, and wider than the diameter of the cooling medium conduit right adjacent to the large diameter part.

CONSTITUTION: A quick connect coupling 20 is rotatably installed on an expansion valve main body 10 by a threaded tightening metal 18 and a washer 44, and at least one of cooling medium conduits 14, 16 is fixed to the expansion valve main body 10. The quick connect coupling 20 is engaged with radial flange parts 46, 48 formed on the cooling medium conduits 14, 16 to fix the cooling medium conduits 14, 16 to the expansion valve main body 10. The quick connect coupling 20 is normally S-formed, and openings 38, 40 are provided with forms of chamfered slots 42a, 42b. The minimum width of each slot 42a, 42b is smaller than an outer diameter of a large diameter part 52, 54 of the corresponding cooling medium conduit 14, 16. The cooling medium conduits 14, 16 are not removed from the openings 38, 40, therefore, while the quick connect coupling 20 is engaged with the large diameter parts 52, 54 of the cooling medium conduits 14, 16.