Brake system, anti-lock brake system with automatic brake differential ABD/ETS, function

D42.30-0019-06

"Rear right" brake circuit with ABD braking, switchover valve (USV1) switch position "pressure holding", solenoid valve (ASV1) switch position "pressure passage"

A1 Hydraulic unit

ASV ABD intake valve

AVHL ABS solenoid valve, pressure reducing, rear left

AVHR ABS solenoid valve, pressure reducing, rear right

AVVL ABS solenoid valve, pressure reducing, front left

AVVR ABS solenoid valve, pressure reducing, front right

D Damper chamber

EVHL ABS solenoid valve, pressure holding, rear left

EVHR ABS solenoid valve, pressure holding, rear right

EVVL ABS solenoid valve, pressure holding, front left

EVVR ABS solenoid valve, pressure holding, front right

RFP Return pump

RVR Non-return valve

SPK Storage chamber

USV

Pressure curve of the "Rear right" brake circuit in the brake system with ABD braking, switchover valve (USV1) switch position "pressure holding", solenoid valve (ASV1) switch position "pressure passage"

 The brake fluid is pumped from the pump (RFP1) to the wheel brake cylinder via the solenoid valve (ASV1), the damper chamber (D1) and the solenoid valve (EVHR). The brake pressure builds up and the wheel is braked.

 The brake fluid cannot flow back via the solenoid valve (USV1) as this is switched to "pressure holding".

D42.30-0020-06

"Rear right" brake circuit with ABD braking, switchover valve (USV1) switch position "pressure holding", solenoid valve (ASV1) switch position "rest position"

A1 Hydraulic unit

ASV ABD intake valve

AVHL ABS solenoid valve, pressure reducing, rear left

AVHR ABS solenoid valve, pressure reducing, rear right

AVVL ABS solenoid valve, pressure reducing, front left

AVVR ABS solenoid valve, pressure reducing, front right

D Damper chamber

EVHL ABS solenoid valve, pressure holding, rear left

EVHR ABS solenoid valve, pressure holding, rear right

EVVL ABS solenoid valve, pressure holding, front left

EVVR ABS solenoid valve, pressure holding, front right

RFP Return pump

RVR Non-return valve

SPK Storage chamber

Pressure curve of the "Rear right" brake circuit in the brake system with ABD braking, switchover valve (USV1) switch position "pressure holding", solenoid valve (ASV1) switch position "rest position"

 The brake fluid cannot be drawn in by the pump (RFP1) via the solenoid valve (ASV1).

 The pressure between the solenoid valve (USV1) and the wheel brake cylinder is held constant.

D42.30-0021-06

"Rear right" brake circuit with ABD braking, switchover valve (USV1) switch position "pressure reducing", solenoid valve (ASV1) switch position "rest position"

A1 Hydraulic unit

ASV ABD intake valve

AVHL ABS solenoid valve, pressure reducing, rear left

AVHR ABS solenoid valve, pressure reducing, rear right

AVVL ABS solenoid valve, pressure reducing, front left

AVVR ABS solenoid valve, pressure reducing, front right

D Damper chamber

EVHL ABS solenoid valve, pressure holding, rear left

EVHR ABS solenoid valve, pressure holding, rear right

EVVL ABS solenoid valve, pressure holding, front left

EVVR ABS solenoid valve, pressure holding, front right

RFP Return pump

RVR Non-return valve

SPK Storage chamber

Pressure curve of the "Rear right" brake circuit in the brake system with ABD braking, switchover valve (USV1) switch position "pressure reducing", solenoid valve (ASV1) switch position "rest position"

 The pressure is relieved back to the brake master cylinder via the solenoid valve (EVHR) and the switchover valve (USV).

 The complete pressure reducing therefore takes place via the solenoid valve (USV1).