Method for operating a brake system of a motor vehicle, brake system, motor vehicle

Patent metadata

Field	Value
Publication number	US-11524668-B2
Application number	US-201916538357-A
Country	US
Kind code	B2
Filing date	Aug 12, 2019
Priority date	Oct 18, 2018
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

A method is provided for operating a motor vehicle brake system that includes an actuatable brake master cylinder, a hydraulic brake booster, and at least one brake circuit that has at least one hydraulically actuatable wheel brake and at least one hydraulic-pressure generator driven by electric motor. The method includes monitoring a state of actuation of the brake master cylinder is monitored, and, upon detecting a maximum state of actuation, activating the hydraulic-pressure generator to increase the hydraulic pressure adjusted by the brake master cylinder in the brake circuit.

First claim

What is claimed is:

1. A method for operating a brake system of a motor vehicle, the brake system comprising an actuatable brake master cylinder, a hydraulic brake booster, and at least one brake circuit that each includes at least one hydraulically actuatable wheel brake and at least one hydraulic-pressure generator driven by an electric motor, the method comprising:
monitoring a state of actuation of the brake master cylinder; and
for each of the at least one brake circuit, upon detecting a maximum of the state of actuation, activating the respective hydraulic-pressure generator of the brake circuit to increase a hydraulic pressure adjusted by the brake master cylinder in the respective brake circuit;
wherein the method includes either or both of the following features (a)-(b):
(a) the maximum of the state of actuation, upon detection of which the activating of the respective hydraulic-pressure generator of the brake circuit is performed, is a maximum extension of a piston located in the brake master cylinder; and
(b) the respective hydraulic-pressure generator at least one of:
(i) is separate from the brake booster;
(ii) is located in a line downstream of an outlet from a fluid chamber of the brake master cylinder; and
(iii) includes a hydraulic pump, with a pressure accumulator of the brake system being arranged at a suction side of the hydraulic pump.

2. The method of claim 1 , wherein the state of actuation of the brake master cylinder is ascertained using a hydraulic-pressure sensor.

3. The method of claim 1 , wherein the hydraulic-pressure generator is activated as a function of an instantaneous driving speed of the motor vehicle.

4. The method of claim 1 , wherein the hydraulic-pressure generator is activated as a function of an instantaneous deceleration of the motor vehicle.

5. The method of claim 1 , wherein the hydraulic-pressure generator is activated as a function of a duration of the actuation of the brake master cylinder.

6. The method of claim 1 , wherein the activation of the hydraulic-pressure generator increases the hydraulic pressure a maximum amount possible.

7. The method of claim 1 , wherein the activation of the hydraulic-pressure generator increases the hydraulic pressure iteratively step-by-step.

8. The method of claim 1 , wherein the activation of the hydraulic-pressure generator increases the hydraulic pressure continuously.

9. The method of claim 1 , wherein the activation of the hydraulic-pressure generator increases the hydraulic pressure as quickly as possible.

10. The method of claim 1 , wherein the maximum of the state of actuation, upon detection of which the activating of the respective hydraulic-pressure generator of the brake circuit is performed, is the maximum extension of the piston located in the brake master cylinder.

11. The method of claim 1 , wherein the respective hydraulic-pressure generator is separate from the brake booster.

12. The method of claim 1 , wherein the respective hydraulic-pressure generator is located in a line downstream of an outlet from a fluid chamber of the brake master cylinder.

13. The method of claim 12 , wherein the activation of the respective hydraulic-pressure generator causes the respective hydraulic-pressure generator to increase a pressure of fluid that has been output from the fluid chamber of the brake master cylinder and that is being input to one or more of the at least one hydraulically actuatable wheel brake.

14. The method of claim 1 , wherein the respective hydraulic-pressure generator includes the hydraulic pump, with the pressure accumulator of the brake system being arranged at the suction side of the hydraulic pump.

15. A brake system for a motor vehicle, the brake system comprising:
an actuatable brake master cylinder;
a hydraulic brake booster;
at least one brake circuit that each includes at least one hydraulically actuatable wheel brake; and
a control unit, wherein:
the control unit is configured to:
monitor a state of actuation of the brake master cylinder; and
for each of the at least one brake circuit, upon detecting a maximum of the state of actuation, activate a respective hydraulic-pressure generator of the brake circuit to increase a hydraulic pressure adjusted by the brake master cylinder in the respective brake circuit; and

the brake system includes either or both of the following features (a)-(b):
(a) the maximum of the state of actuation, upon detection of which the activation of the respective hydraulic-pressure generator of the brake circuit is performed, is a maximum extension of a piston located in the brake master cylinder; and
(b) the respective hydraulic-pressure generator at least one of:
(i) is separate from the brake booster;
(ii) is located in a line downstream of an outlet from a fluid chamber of the brake master cylinder; and
(iii) includes a hydraulic pump, with the brake system further comprising a pressure accumulator arranged at a suction side of the hydraulic pump.

16. A motor vehicle comprising a brake system, the brake system comprising:
an actuatable brake master cylinder;
a hydraulic brake booster;
at least one brake circuit that each includes at least one hydraulically actuatable wheel brake; and
a control unit, wherein:
the control unit is configured to:
monitor a state of actuation of the brake master cylinder; and
for each of the at least one brake circuit, upon detecting a maximum of the state of actuation, activate a respective hydraulic-pressure generator of the brake circuit to increase a hydraulic pressure adjusted by the brake master cylinder in the respective brake circuit; and

the brake system includes either or both of the following features (a)-(b):
(a) the maximum of the state of actuation, upon detection of which the activation of the respective hydraulic-pressure generator of the brake circuit is performed, is a maximum extension of a piston located in the brake master cylinder; and
(b) the respective hydraulic-pressure generator at least one of:
(i) is separate from the brake booster;
(ii) is located in a line downstream of an outlet from a fluid chamber of the brake master cylinder; and
(iii) includes a hydraulic pump, with the brake system further comprising a pressure accumulator arranged at a suction side of the hydraulic pump.

Assignees

• Bosch Gmbh Robert

Inventors

• Reize Andreas
• Harrer Dino
• Epple Stefan

Classifications

• B60T7/12

  for automatic initiation; for initiation not subject to will of driver or passenger {(limiting speed of vehicles other than rail vehicles B60K31/00)} · CPC title

• B60T8/4054

  involving the delivery pressure control (B60T8/4072 takes precedence) · CPC title

• B60T2250/04

  Vehicle reference speed; Vehicle body speed · CPC title

• B60T2201/03

  Brake assistants · CPC title

• B60T7/042

  by electrical means, e.g. using travel or force sensors · CPC title