摘要 |
In order to reduce the forces transmitted by the reaction device of a vacuum brake booster, there is provided a first booster piston directly connected to the booster's output member and a second booster piston of smaller size acting solely on the reaction device. Both booster pistons are controlled by a control valve carried by the second booster piston. The second booster piston is arranged inside an internal cylindrical sleeve penetrating the first booster piston and interconnecting the transverse end walls of the booster housing. |