ACCUMULATOR

PROBLEM TO BE SOLVED: To provide an accumulator capable of being miniaturized while securing necessary initial extrusion pressure and extrusion output. SOLUTION: A diaphragm 30 has a first deformation state where only a central part 30a is deformed and a pressure receiving area permitting the inflow of liquid into the accumulator is small, and a second deformation state where the whole part (central part 30a and outer ring part 30b) in contact with the liquid is deformed and the pressure receiving area permitting the inflow of liquid to the accumulator is large. A first compression coil spring 44 for energizing the diaphragm 30 to a liquid discharge side in the first deformation state of small pressure receiving area, and a second compression coil spring 46 for energizing the diaphragm 30 to the liquid discharge side in the second deformation state of large pressure receiving area, are used. Thus different (extrusion pressure)-(extrusion output) properties can be achieved between low extrusion pressure and high extrusion pressure by adjusting the energizing forces of the first compression coil spring 44 and the second compression coil spring 46. COPYRIGHT: (C)2007,JPO&INPIT