Reservoir for a master cylinder

A reservoir for a master cylinder which comprises a reservoir body adapted to be placed above and secured to a master cylinder body and having a top opening defined by a top peripheral edge portion, a cap adapted to be secured to the reservoir body for closing the top opening, a flexible diaphragm disposed between the reservoir body and the cap, said diaphragm including a flexible portion substantially covering the top opening of the reservoir body and a peripheral portion adapted to be interposed between the top peripheral edge portions of the reservoir body and the cap, a depressing plate interposed between the peripheral portions of the diaphragm and the cap, and restraining means provided on the depressing plate for engagement with the peripheral portion of the diaphragm to thereby restrain it from a radially inward movement, said cap being provided with a pair of hook-shaped portions for engagement with an outer edge of said depressing plate for securing said depressing plate to said cap, and said diaphragm being formed with a pair of inward projections engaging apertures in said depressing plate for securing said diaphragm to said depressing plate such that said cap, depressing plate, and diaphragm form a sub-assembly to be placed on the reservoir body.