Power amplifier, in particular for actuating the brakes of vehicles

摘要

A reaction device (72) for transmitting a reaction force, proportional to the useful power, from a power-output member (74) to an actuating member (70) has a stepped cylinder (76) which is produced as a sheet-metal stamping and which in a wide cylinder part (78) accommodates a deformable body (80) of constant volume as well as a piston-like head piece (82) of the power-output member (74) and in a narrower cylinder part (84) accommodates a piston-like end piece (86) of the actuating member (70). The deformable body (80) is put in the raw state into the sheet-metal stamping and sets therein. The front and rear end faces (D and E) of the deformable body (80) thereby retain an exactly defined position, and the body completely fills the inner space of the sheet-metal stamping between these two end faces (D and E) so that it transmits a reaction force, corresponding to the useful power in an exactly reproducible relationship, from the power-output member (74) back to the actuating member (70). <IMAGE>