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US 12,030,471 B2Granted
Method for monitoring a hydraulic brake system for a motor vehicle and brake system
AssigneeContinental Teves AG & Co. oHG
InventorsChristian Courth, Anne Seidel, Ulrich Lohse, Andreas Neu, Roland Caspari
Life of this patent
Estimating the term…
Abstract
A method for monitoring a hydraulic brake system for a motor vehicle, wherein a diagnostic valve is omitted and, instead, air volume and leakage are identified by a volume balance during generation of a dynamic pressure. An associated brake system is also disclosed.
Claims14
A method for monitoring a hydraulic brake system for a motor vehicle,
- wherein the brake system has the following:
- a master brake cylinder with at least one breather hole,
- an electrically operated pressure generator,
- a simulator comprising a simulator piston and a simulator spring disposed within an interior of the simulator,
- a simulator valve, and
- a main line,
- wherein the master brake cylinder is connected to the pressure generator via the main line and the simulator is connected via the simulator valve to the main line, between the master brake cylinder and the pressure generator,
- wherein the method comprises:
- generating a volume flow by the pressure generator, wherein the volume flow flows from the pressure generator via the main line to the master brake cylinder and exits the latter via the breather hole,
- establishing a volume balance as the difference between the volume that has been discharged from the pressure generator into the main line up to a particular time minus a volume that has exited the master brake cylinder via the breather hole up to the particular time, and
- identifying a state of the brake system on the basis of the volume balance or on the basis of a profile with respect to time of the volume balance,
- wherein the volume that has exited the master brake cylinder via the breather hole up to the particular time is determined by integration of an outflow of the volume flow through the breather hole over time,
- wherein the outflow is determined on the basis of an aperture parameter and a measured pressure in the brake system or in the master brake cylinder, and
- wherein the aperture parameter is determined iteratively;
- and/or determined by a parameter estimation method, such that the volume flow and the outflow are equal in the steady state.
12 more elements
A method for monitoring a hydraulic brake system for a motor vehicle,
- wherein the brake system has the following:
- a master brake cylinder with at least one breather hole,
- an electrically operated pressure generator,
- a simulator comprising a simulator piston and a simulator spring disposed within an interior of the simulator,
- a simulator valve, and
- a main line,
- wherein the master brake cylinder is connected to the pressure generator via the main line and the simulator is connected via the simulator valve to the main line, between the master brake cylinder and the pressure generator,
- the method comprising:
- generating a volume flow by the pressure generator, wherein the volume flow flows from the pressure generator via the main line to the master brake cylinder and exits the latter via the breather hole,
- establishing a volume balance as the difference between the volume that has been discharged from the pressure generator into the main line up to a particular time minus a volume that has exited the master brake cylinder via the breather hole up to the particular time, and
- identifying a state of the brake system on the basis of the volume balance or on the basis of a profile with respect to time of the volume balance,
- wherein the volume that has exited the master brake cylinder via the breather hole up to the particular time is determined by integration of an outflow of the volume flow through the breather hole over time,
- wherein the outflow is determined on the basis of an aperture parameter and a measured pressure in the brake system or in the master brake cylinder, and
- wherein the outflow is determined:
- as a product of aperture parameter and the square root of the pressure;
- and/or
- as a product of the aperture parameter and pressure;
- and/or
- as a sum of a product of a first one of the aperture parameter and the pressure, on the one hand, and a product of a second one of the aperture parameter and the square root of the pressure, on the other hand.
16 more elements
A method for monitoring a hydraulic brake system for a motor vehicle,
- wherein the brake system has the following:
- a master brake cylinder with at least one breather hole,
- an electrically operated pressure generator,
- a simulator,
- a simulator valve, and
- a main line,
- wherein the master brake cylinder is connected to the pressure generator via the main line and the simulator is connected via the simulator valve to the main line, between the master brake cylinder and the pressure generator,
- wherein the method comprises:
- generating a volume flow by the pressure generator, wherein the volume flow flows from the pressure generator via the main line to the master brake cylinder and exits the latter via the breather hole,
- establishing a volume balance as the difference between the volume that has been discharged from the pressure generator into the main line up to a particular time minus a volume that has exited the master brake cylinder via the breather hole up to the particular time,
- identifying a state of the brake system on the basis of the volume balance or on the basis of a profile with respect to time of the volume balance,
- generating the volume flow for a first period of time with the simulator valve open, subsequently
- closing the simulator valve for a second period of time with the pressure generator deactivated, subsequently
- generating the volume flow for a third period of time with the simulator valve open, and ascertaining leakage of the simulator valve in the third period of time on the basis of a volume balance.
11 more elements
Dependencies are inferred from the claim text.