Patent ID: 11332108

Abstract:
A brake system (20) for a vehicle includes a brake unit (20A; 20B) having: a fluid reservoir (32) for containing a volume of brake fluid therein, an ECU (1000), and an electronically-controlled plunger device (60) operable to stroke in response to a control signal from the ECU (1000) to supply fluid pressure to at least one wheel cylinder (RL, RR) for vehicle braking. The plunger device (60) includes: a rod (108) coupled to an actuator (M), a primary seal (100) coupled to the rod (108) and arranged to seal against an inner wall of a plunger chamber, and a secondary seal (104) surrounding the rod (108) to seal an interface where the rod (108) exits the plunger chamber. A portion of the plunger chamber between the primary and secondary seals (100, 104) is coupled through a switchable valve (112) to the fluid reservoir (32). A method of operating a brake system (20) for self-contained brake circuit filling comprises the steps of providing a brake unit (20A; 20B), performing a pressure bleed on a first portion of a brake circuit, supplying pressurized brake fluid to a wheel (RL) coupled to the first portion and supplying brake fluid from a reservoir (32) to a second portion of the brake circuit by switching a valve (112) while using a plunger device (60) under control of an ECU (1000).