Power brake system
The invention relates to a spring-force brake system having a brake operating unit, having at least one sensor for detecting a driver braking demand upon operation of the brake operating unit by the driver, having at least one actuation unit for setting and regulating a braking force. For this purpose, it is provided according to the invention that at least one primary electronic control and regulating unit is provided which is connected at the signal input side to at least one sensor and which activates the actuation unit as a function of or on the basis of the signals of the sensor, and that at least one secondary control and regulating unit is provided which is connected at the signal input side to at least one sensor and which activates the actuation unit on demand on the basis of or as a function of signals of the sensor.
1. A power brake system with a brake operating unit, with at least one sensor for detecting a driver's braking demand when the brake operating unit is operated by the driver, with at least one actuating unit for setting and adjusting a brake force, and with a primary electronic control and regulating unit, which is connected on a signal input side thereof to at least one sensor and activates the at least one actuating unit on demand in dependence on signals of said at least one sensor, and with at least one secondary control and regulating unit, which is connected on a signal input side thereof to at least one sensor and activates the at least one actuating unit on demand in dependence on the signals of said at least one sensor,
wherein the at least one actuating unit comprise electric motor, and
wherein the electric motor is of a two-part configuration with a first and a second component, and wherein the first component is activated by the primary control and regulating unit and the second component is activated by the at least one secondary control and regulating unit.
2. The power brake system as claimed in claim 1 , wherein the primary control and regulating unit has a separate energy supply that is independent of the energy supply of the secondary control and regulating unit.
3. The power brake system as claimed in claim 1 , wherein the primary control and regulating unit and the at least one secondary control and regulating unit are configured in compliance with a prescribed safety requirement, in such a way that the primary control and regulating unit and the at least one secondary control and regulating unit together meet the prescribed safety requirement, each of the control and regulating units in itself conforming to a low safety requirement.
4. The power brake system as claimed in claim 3 , wherein the prescribed safety requirement is ASIL D and the low safety requirement is ASIL B.
5. The power brake system as claimed in claim 1 , wherein the at least one actuating unit further comprises an actuator, which transforms a rotary movement of a motor spindle of the electric motor into a translatory movement of a primary piston of a tandem brake master cylinder, the tandem brake master cylinder having two chambers, each chamber being hydraulically connected to a respective brake circuit with each brake circuit having two wheel brakes.
6. The power brake system as claimed in claim 5 , wherein the actuator comprises a gear mechanism and a spindle unit.
7. The power brake system as claimed in claim 1 , further comprising another one of the at least one actuating unit, which can be activated by the at least one secondary control and regulating unit.
8. The power brake system as claimed in claim 7 , wherein the at least one secondary control and regulating unit and the at least one actuating unit have together a separate energy supply that is independent of the energy supply of the primary control and regulating unit.
9. The power brake system as claimed in claim 1 , further comprising a travel sensor of a redundant configuration and/or a pressure sensor of a redundant configuration.
10. The power brake system as claimed in claim 1 , wherein the operating unit comprises a brake pedal and a simulator.
11. The power brake system as claimed in claim 1 , wherein the electric motor is an electronically commutating BLDC motor.