Vehicle braking system

A vehicle braking system comprising:

• a primary braking unit having a master cylinder operable to selectively provide pressurized fluid to an outlet port of the primary braking unit and a first pressure generating unit operable to selectively provide pressurized fluid to the outlet port of the primary braking unit;
• a secondary braking unit having an inlet port connected to the outlet port of the primary braking unit and a second pressure generating unit operable to selectively provide pressurized fluid to an outlet port of the secondary braking unit;
• and
• a controllable separation valve positioned between a discharge side of the second pressure generating unit and the wheel cylinder such that pressurized fluid from the discharge side of the second pressure generating unit is selectively connected to the wheel cylinder for braking on a path that extends through the controllable separation valve,
• wherein the primary braking unit and the secondary braking unit form a combined braking system having an outlet connecting the combined braking system to a wheel cylinder, and
• wherein the outlet of the combined braking system is provided in the secondary braking unit.

A vehicle braking system comprising:

• a master cylinder;
• a wheel cylinder;
• a first valve block defining a primary braking unit having a first pressure generating unit, the first valve block including:
• a first outlet port;
• a first flow passage extending between the master cylinder and the first outlet port;
• and
• one or more ABS valves in the first flow passage operable to control traction control and anti-lock braking;
• and
• a second valve block defining a secondary braking unit having a second pressure generating unit, the second valve block including:
• a secondary inlet port in communication with the first outlet port of the first valve block;
• a second outlet port in direct communication with the wheel cylinder without intervening valving;
• a second flow passage extending between the second inlet port and the second outlet port;
• and
• one or more ABS valves in the second flow passage operable to control traction control and anti-lock braking.

A vehicle braking system comprising:

• a primary braking unit having a master cylinder operable to selectively provide pressurized fluid to an outlet port of the primary braking unit and a first pressure generating unit operable to selectively provide pressurized fluid to the outlet port of the primary braking unit;
• and
• a secondary braking unit having an inlet port connected to the outlet port of the primary braking unit and a second pressure generating unit operable to selectively provide pressurized fluid to an outlet port of the secondary braking unit;
• wherein the primary braking unit and the secondary braking unit form a combined braking system having an outlet connecting the combined braking system to a wheel cylinder,
• wherein the outlet of the combined braking system is provided in the secondary braking unit, and
• wherein the primary braking unit includes a first reservoir and the secondary braking unit includes a second reservoir, wherein the second pressure generating unit is a motor-driven pump, and wherein the secondary braking unit includes a bleed-off valve configured to selectively bleed off fluid from the pump to the second reservoir.

A vehicle braking system comprising:

• a master cylinder;
• a wheel cylinder;
• a primary braking unit including a first pressure generating unit distinct from the master cylinder and operable to actuate a braking action at the wheel cylinder in a primary mode of operation, and an outlet port connecting the primary braking unit to the wheel cylinder;
• a secondary braking unit including a second pressure generating unit distinct from the master cylinder and operable to actuate a braking action at the wheel cylinder in a secondary mode of operation, and
• an input device,
• wherein the secondary braking unit has an inlet port connected to the outlet port of the primary braking unit;
• wherein the primary braking unit includes one or more ABS valves operable to control traction control and anti-lock braking in the primary mode of operation and located between the first pressure generating unit and the outlet port of the primary braking unit, wherein the secondary braking unit is located between the one or more ABS valves and the wheel cylinder, and
• wherein the first pressure generating unit is operable in response to a user input to the input device in the first mode of operation, and wherein the second pressure generating unit is operable independent of the user input device in the second mode of operation.