Abstract: A pneumatic brake booster (10), in particular for motor vehicles, is described. The pneumatic brake booster (10) has a control valve (22) for controlling a pneumatic pressure difference, a force input element (24) for actuating the control valve (22), a force output element (38) for transmitting the braking force as well as a reaction disk (34) of elastomer material disposed between the force output element (38) and the force input element (24). Disposed between the reaction disk (34) and the force input element (24) and acting upon the reaction disk (34) is a unit (30) for altering the force transmission ratio between the force input element (24) and the force output element (38) in dependence upon the force exerted upon the force input element (24). The unit (30) comprises a displaceable inner piston (50) as well as an outer piston (54), which surrounds the radially outer side of the inner piston (50) and is displaceable relative to the inner piston (50).

Abstract: A vacuum brake booster (10) is described, having a vacuum chamber (16) and a working chamber (18) separated from one another by a movable wall (14), and a control valve (20), which comprises a housing (12) coupled workingly to the movable wall (14) and which to achieve a pressure difference at the movable wall (14) is capable of controlling the supply of atmospheric pressure or above-atmospheric pressure to the working chamber (18) in dependence upon the displacement of an actuating piston (28). The vacuum brake booster (10) has an emergency braking aid comprising a permanent magnet (38) and an armature (36), which cooperates with the permanent magnet (38) and is resiliently biased counter to actuating direction and during an emergency braking operation is drawn into abutment with the permanent magnet (38), with the result that the control valve (20) is held open for the supply of atmospheric pressure to the working chamber (18).

Abstract: A vacuum brake booster (10) is described, having a vacuum chamber (16) and a working chamber (18) separated from one another by a movable wall (14), and a control valve (20), which comprises a housing (12) coupled workingly to the movable wall (14) and which to achieve a pressure difference at the movable wall (14) is capable of controlling the supply of atmospheric pressure or above-atmospheric pressure to the working chamber (18) in dependence upon the displacement of an actuating piston (28). The vacuum brake booster (10) has an emergency braking aid comprising a permanent magnet (38) and an armature (36), which cooperates with the permanent magnet (38) and is resiliently biased counter to actuating direction and during an emergency braking operation is drawn into abutment with the permanent magnet (38), with the result that the control valve (20) is held open for the supply of atmospheric pressure to the working chamber (18).

Abstract: A pneumatic brake booster (10), in particular for motor vehicles, is described. The pneumatic brake booster (10) has a control valve (22) for controlling a pneumatic pressure difference, a force input element (24) for actuating the control valve (22), a force output element (38) for transmitting the braking force as well as a reaction disk (34) of elastomer material disposed between the force output element (38) and the force input element (24). Disposed between the reaction disk (34) and the force input element (24) and acting upon the reaction disk (34) is a unit (30) for altering the force transmission ratio between the force input element (24) and the force output element (38) in dependence upon the force exerted upon the force input element (24). The unit (30) comprises a displaceable inner piston (50) as well as an outer piston (54), which surrounds the radially outer side of the inner piston (50) and is displaceable relative to the inner piston (50).

Abstract: A pneumatic brake booster (10) comprises a control valve (22) for controlling a pneumatic pressure difference, a force input element (24) for actuating the control valve (22), a force output element (38) for transmitting the braking force, a reaction disk (34) made of elastomeric material disposed between the force output element (38) and the force input element (24), and a device, which is disposed between the reaction disk (34) and the force input element (24) and acts upon the reaction disk (34), for varying the force transmission ratio between force input element (24) and force output element (38) in dependence upon the force exerted on the force input element (24). For a less expensive design and greater ease of assembly, the device for varying the force transmission ratio is designed as a preassembly unit in the form of a cartridge (30), which after preassembly is insertable into the control valve (22).

Abstract: A pneumatic brake booster (10) comprises a control valve (22) for controlling a pneumatic pressure difference, a force input element (24) for actuating the control valve (22), a force output element (38) for transmitting the braking force, a reaction disk (34) made of elastomeric material disposed between the force output element (38) and the force input element (24), and a device, which is disposed between the reaction disk (34) and the force input element (24) and acts upon the reaction disk (34), for varying the force transmission ratio between force input element (24) and force output element (38) in dependence upon the force exerted on the force input element (24). For a less expensive design and greater ease of assembly, the device for varying the force transmission ratio is designed as a preassembly unit in the form of a cartridge (30), which after preassembly is insertable into the control valve (22).