Patent ID: 9643582
Date: 2017-05-09
CPC Classifications: B60T

Claim:
1. A master brake cylinder for a braking system of a vehicle, comprising: a first filling volume for filling with liquid, wherein at least one dimension of the first filling volume is variable by adjusting at least one first piston wall; a second filling volume for filling with liquid, wherein at least one dimension of the second filling volume is variable by adjusting at least one second piston wall; and a valve unit, wherein the first filling volume is connected via the valve unit to the second filling volume in such a way that (i) when the valve unit is switched into a first valve state, a shared pressure chamber pressure prevails in the first filling volume and in the second filling volume, and a brake application volume of a pressure chamber of the master brake cylinder includes at least the first filling volume and the second filling volume, to produce a first ratio of brake pressure provided by the pressure chamber to brake force exerted on at least one piston having the at least one first and second piston walls, and (ii) when the valve unit is switched into a second valve state, the brake application volume of the pressure chamber of the master brake cylinder includes at least the first filling volume and is separated from the second filling volume, to produce a second ratio of the brake pressure to the brake force, the second ratio being greater than the first ratio, wherein the valve unit is switched into the second valve state in response to a failure of a brake force booster device.