| 摘要 |
PROBLEM TO BE SOLVED: To protect a shape memory alloy of a small valve using the shape memory alloy from overload, and increase durability and reliability of the valve. SOLUTION: The small valve is equipped with a movable valve element 3 having a sealing part 5 internally coming into contact with a guide pipe 1 to close an orifice 2, a bias coil 8 installed between the orifice 2 and the movable valve element 3, and a wire 9 formed of the shape memory alloy held between a fixed electrode 11 of the guide pipe 1 and a movable electrode 12 of the movable valve element 3. The wire 9 is heated to deform the shape memory alloy so as to move the movable valve element 3 in order to close the orifice 2. A coiled spring 7 for stress reduction is disposed in the movable valve element 3 to elastically deform the movable valve element 3 so that an overload on the movable valve element 3 due to excessive contraction of the wire 9 can be absorbed by the elastic deformation of the movable valve element 3 itself. Therefore, reoccurrence of a memorized shape can be prevented from being deteriorated by reducing the overload of the shape memory alloy, and the durability and the reliability of the valve can be increased. COPYRIGHT: (C)2007,JPO&INPIT |
