To provide a bidirectional constant pressure expansion valve capable of reducing costs in comparison with a conventional one.

According to this bidirectional constant pressure expansion valve 10, a refrigerant pressure at a downstream side can be made constant. As diaphragms 34 are used for bellows 4 used as a pressure sensitive member in a conventional bidirectional constant pressure expansion valve, costs can be reduced. Further as the diaphragms 34 are disposed by every valve port 16A, 16B to change valve openings of each of the valve ports 16A, 16B, characteristics of the valve opening to refrigerant pressure, of the valve port 16B at an indoor heat exchanger 92A side and characteristics of the valve opening to refrigerant pressure, of the valve port 16A at an outdoor heat exchanger 91A side can be respectively properly set.

COPYRIGHT: (C)2007,JPO&INPIT