Abstract: A master cylinder assembly wherein pressure cylinders are formed in a body and interconnected by a transfer passage through which fluid flow is controlled by valve elements. The valve elements are operated in response to actuating pressure in the cylinders and are opened by this pressure to interconnect the cylinders when the latter are pressurized simultaneously. When only one cylinder is pressurized, the valve elements associated with other cylinders remain closed to prevent fluid flow through the transfer passage. The valve elements have stems which control expulsion of fluid from the cylinders through outlets.

Abstract: A self-energizing disc brake of the spreading type is applied by a pair of oppositely acting hydraulic pistons which work in a common bore in the housing of the brake. One piston acts directly on an adjacent lug on a pressure plate and the other piston acts on a lug on a pressure plate through a transmission member which extends through the piston and may be coupled at its outer end to a hand-brake or similar lever.