Abstract: In a method of manufacturing a brake booster, a step of defining a fixed distance between a peripheral surface on a rear shell of the brake booster and an eye of a linkage member attached to a brake pedal when the movable wall is in a rest position, The wall in the brake booster is adapted to be rotated with respect to a variable surface on the rear shell which acts as a stop for the wall in the rest position. The location of the wall with respect to the variable surface establishes a desired fixed linear dimension between a peripheral surface on the rear shell and an eye on the linkage member which is attached to connecting pin the brake pedal. When the control valve is in the rest position this fixed linear dimension also defines a corresponding fixed location for the pad of the brake pedal with respect to a floor panel in a vehicle.

Abstract: In a method of manufacturing a brake booster, a step of defining a fixed distance between a peripheral surface on a rear shell of the brake booster and an eye of a linkage member attached to a brake pedal when the movable wall is in a rest position. The wall in the brake booster is adapted to be rotated with respect to a variable surface on the rear shell which acts as a stop for the wall in the rest position. The location of the wall with respect to the variable surface establishes a desired fixed linear dimension between a peripheral surface on the rear shell and an eye on the linkage member which is attached to connecting pin the brake pedal. When the control valve is in the rest position this fixed linear dimension also defines a corresponding fixed location for the pad of the brake pedal with respect to a floor panel in a vehicle.

Abstract: A poppet valve for a vacuum brake booster. The poppet valve is connected to a key number which retains a control valve in a bore of a hub of a brake booster. The poppet valve controls fluid communication between a first chamber and a second chamber in the booster while the control valve only controls fluid communication between the bore and the second chamber.

Abstract: A brake booster (12) and check valve (36) wherein the housing (38) of the check valve (36) has a plurality of legs (52, 52'. . . 52.sup.N) with a disc (56) located thereon. The legs (52, 52'. . . 52.sup.N) which extend through slots (55, 55'. . . 55.sup.N) in the shell (30) of the brake booster (12) have tabs (54, 54'. . . 54.sup.N) that lock the housing (38) to the shell (30). The disc (56) has an annular rib (58) which engages the shell (30) to form a seal to prevent air from entering chambers (24, 40). The housing (38) is connected to a source of vacuum and a flapper (60) positioned over a plurality of openings (32, 32'. . . 32.sup.N) in the shell (30) to allow vacuum in the chamber (40) to evacuate air from the brake booster (12).

Abstract: A check valve for use in the evacuation of air from a system having primary and secondary disc retained in a chamber of the housing and responsive to first and second forces developed by the creation of a fluid pressure differential between the fluid pressure of air in a first member and a source of vacuum to control the evacuation of air from the member by the source of vacuum. The primary disc is located on a stem that extends from the secondary disc to cover a plurality of openings which connect the inlet port to the chamber. A spring holds the secondary disc against the housing. The first force which develops as a result of a pressure differential between the fluid pressure of air and vacuum moves the primary disc to allow air to be evacuated through the openings in the secondary disc. Should the fluid pressure in the air located in the first member exceed a predetermined value, the second force develops which acts on the secondary disc to allow a larger volume of air to be evacuated in a shorter time.

Abstract: A method of manufacturing a push rod (10) for a brake booster. The push rod (10) has a stem (12) connected to a head (14). Head (14) is formed from a blank (30) by first machining an axial cavity (36) in an end 34 in a cylindrical body and then fine blanking an axial projection (46) on the other end (32). Thereafter, the depth of the cavity (36) is finalized and an opening (52) drilled along the central axis of the blank (30) to produce the head (14). On insertion of the stem (12) in the opening (52) the push rod (10) is produced.