| 摘要 |
PURPOSE:To prevent the generation of permanent deformation by applying a coil winding means and a shape memory working means to a shape memory alloy spring, and then a surface cold working means to same. CONSTITUTION:A coiled shape memory alloy spring 18 made of a Ni-Ti alloy for always urging an up-and-down valve 14 in the closing direction is installed between the upper inner surfaces between the up-and-down valve 14 and a valve body 16, and a bias spring 19 for always urging the up-and-down valve 14 in the opening direction is installed between the upper end flange portion 14b of a projecting shaft portion 14a of the up-and-down valve 14 and the upper outer surface of a valve body 16. The spring 18 is formed by applying a coil winding means, a shape memory alloy working means at normal temperature, and then a surface cold working means to shift the transformation temperature to the high temperature side. |
