
A reservoir fluidically connected to a fluid pressure source and comprising, a casing, a projection projected from one end of the casing into the casing and fixedly connected with the casing, a cylindrical member sealed hermetically and slidably mounted on the projection, a groove formed between a peripheral surface of the cylindrical member and an end portion of the projection and fluidically connected with the fluid pressure source, a chamber formed between the other end of the casing and an o...











