| 摘要 |
<p>The invention concerns a motor vehicle braking device, comprising a master cylinder (2), a primary piston (3) subjected to an actuating input force exerted by a manually controlled member (4) and an assist force exerted by a brake booster unit (6) which is coupled to the manually controlled member (4), and an assist emergency valve (VA) including: a reaction piston (19) subjected to the action of elastic return means (22) towards a neutral position and sealingly sliding in a bore (20) of the primary piston; a rapid piston (22) with smaller cross-section than that of the reaction piston (19) sealingly sliding in another bore with corresponding diameter; and a ratio control (27) actuated by a distributor plunger (10) driven itself by the manually controlled member (4). The elastic means (22) of the reaction piston (19) is arranged outside the primary piston (5), and a transmission element (T) is provided to transmit the spring force of the elastic means (22) to the reaction piston (19).</p> |
