# US 2023/0053950 A1 · Brake system and method for controlling a brake system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0053950 A1 - Document ID: US20230053950A1 - Status: Published application - Kind: A1 - Application number: 17/795,790 - Filed: 2021-01-27 - Published: 2023-02-23 - Earliest claimed: 2020-01-28 - Assignees: Ipgate AG - Applicants: Ipgate AG - Inventors: Heinz LEIBER; Thomas LEIBER - Web page: https://patentgrep.com/patent/US20230053950A1 ## CPC - B60T 17/221: {Procedure or apparatus for checking or keeping in a correct functioning condition of brake systems (hydraulic pressure systems in general F15B19/00, F15B21/04; testing structures or apparatus G01M)} - B60T 8/1764: Regulation during travel on surface with different coefficients of friction, e.g. between left and right sides, mu-split {or between front and rear} - B60T 8/885: {using electrical circuitry} - B60T 13/745: {acting on a hydraulic system, e.g. a master cylinder} - B60T 2201/12: Pre-actuation of braking systems without significant braking effect; Optimizing brake performance by reduction of play between brake pads and brake disc - B60T 2210/124: Roads with different friction levels - B60T 2270/402: Back-up - B60T 2270/408: Hierarchical failure detection - B60T 2270/416: Wheel speed sensor failure - B60T: VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL (electrodynamic brake systems for vehicle, in general B60L; brakes per se, i.e. devices where braking effect occurs, including ultimate brake actuators, F16D); ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES ## Abstract A brake system and a method for controlling a brake system. The brake system may include a first module having a first pressure supply unit with an electromotive drive, an optional second pressure supply unit and a first control device for controlling the first pressure supply unit; a second module having a third pressure supply unit, isolation valves and brake-pressure-adjusting valves, and a second control device for controlling the brake-pressure-adjusting valves; and a detection unit for detecting a first case of error. The brake system is designed such that, in the first case of error, in order to provide an ABS function and/or a yaw torque intervention, it implements a (wheel-specific and/or selective) adjustment of the pressures in the wheel brakes by actuating at least one of the brake-pressure-adjusting valves of the second module and/or the isolation valves of the second module and the first pressure supply unit. ## Claims ### Claim 1 A brake system having a first module, comprising a first pressure supply unit having an electromotive drive, an optional second pressure supply unit and a first control apparatus for controlling the first pressure supply unit, wherein the first module is specified for impinging at least one first brake circuit by way of a first connection point, and at least one second brake circuit by way of a second connection point, with a pressurizing medium, wherein the brake circuits are assigned wheel brakes, a second module, comprising a third pressure supply unit, in particular a motor/pump unit, isolation valves as well as brake pressure adjustment valves, in particular outlet valves and inlet valves, for adjusting a pressure in the wheel brakes, and a second control apparatus for controlling the brake pressure adjustment valves, a detection unit for detecting a first error event, in particular an at least partial failure of the third pressure supply unit, wherein the brake system in the first error event, for providing an ABS function and/or a yaw torque intervention, is specified for implementing a (wheel-individual and/or selective) adjustment of the pressures in the wheel brakes while actuating at least one of the brake pressure adjustment valves of the second module and/or the isolation valves of the second module and the first pressure supply unit. ### Claim 2 (depends on 1) The brake system as claimed in claim 1, wherein the first pressure supply unit in the first error event is controlled in such a manner that said first pressure supply unit when dissipating pressure for providing the ABS braking operation generates a pressure sink having a lower pressure than the pressures in the wheel brakes. ### Claim 3 (depends on 1) The brake system as claimed in claim 1, wherein at least some of the isolation valves of the first module are disposed and configured for establishing a hydraulic connection between the brake pressure adjustment valves, in particular the outlet valves, and the connection points, wherein the brake system in the first error event, for dissipating pressure in one of the wheel brakes, is preferably configured for opening the assigned outlet valve. ### Claim 4 The brake system as claimed in one of the preceding claims, wherein a communications link, in particular a bus link, is configured between the first control apparatus and the second control apparatus, wherein the first control apparatus is preferably configured for receiving pressure measurement values of the third pressure supply unit and/or wheel rotational speed signals by way of the communications link. ### Claim 5 (depends on 1) The brake system as claimed in claim 1, wherein a communications link, in particular a bus link, is configured between the first control apparatus and the second control apparatus, wherein the first control apparatus and the second control apparatus are preferably configured for receiving pressure measurement values of the third pressure supply unit and/or wheel rotational speed signals by way of the communications link. ### Claim 6 (depends on 1) The brake system as claimed claim 1, wherein the first control apparatus or the second control apparatus or a third control apparatus in the first error event are configured for controlling the first pressure supply unit and the brake pressure adjustment valves so as to implement a wheel-individual and/or brake circuit-individual pressure feedback control in the wheel brakes or the brake circuits. ### Claim 7 (depends on 1) The brake system as claimed in claim 1, wherein a first isolation valve of the first module is disposed in a first hydraulic line between the first pressure supply unit and the first connection point, and a second isolation valve is disposed in a second hydraulic line between the first pressure supply unit and the second connection point, wherein the brake system is configured to detect a second error event, in particular a total failure of the second module, in the second error event to control the first pressure supply unit and the first and the second isolation valve so as to implement at least a brake circuit-individual pressure feedback control in the at least two brake circuits. ### Claim 8 (depends on 7) The brake system as claimed in in claim 7, wherein the brake system, in particular the first control apparatus, is specified to detect a non-homogenous road condition, in particular a μ-split situation, and in the second error event and in the non-homogenous road condition to control the first pressure supply unit so as to adjust in at least one selected brake circuit of the brake circuits a target brake pressure which is determined as a function of a wheel blocking pressure of that wheel brake of the selected brake circuit that has the coefficient of friction that is higher in comparison to the other wheel brake of the selected brake circuit. ### Claim 9 (depends on 1) The brake system as claimed in claim 1, wherein at least the second module has wheel sensors for detecting a wheel speed, said wheel sensors by way of the communications link being specified to transmit wheel rotational speed signals generated from the detected wheel speed, or the detected wheel speed, to the first module, in particular to the first control apparatus. ### Claim 10 (depends on 1) The brake system as claimed in claim 1, wherein the brake system, in particular the first control apparatus, in a third error event, by means of the first pressure supply unit is specified for controlling the pressure buildup and the pressure dissipation, so as to implement a 1-channel ABS while using wheel rotational speed sensors, and/or in a fourth error event is specified for implementing an intermittent brake by modulating the pressure between two fixedly adjusted pressure levels in two brake circuits. ### Claim 11 (depends on 1) The brake system as claimed in claim 1, wherein at least one pressure sensor for detecting a brake pressure within the at least one brake circuit is provided. ### Claim 12 (depends on 1) The brake system as claimed in claim 1, wherein the first module comprises: a rotary pump, in particular a 1-piston pump or a 3-piston pump, for building up pressure and dissipating pressure; a solenoid valve hydraulically connected to a reservoir optionally at least one pressure transducer which for feedback-controlling the pressure buildup and the pressure dissipation is preferably communicatively connected to the first control apparatus. ### Claim 13 (depends on 1) The brake system as claimed in claim 1, wherein the first pressure supply unit is configured as a gear pump for building up pressure and dissipating pressure. ### Claim 14 (depends on 13) The brake system as claimed in claim 13, wherein the gear pump is controlled while using a pressure transducer or as a function of a measurement of a current, in particular a phase current i of the electromotive drive of the gear pump, and of an angle a of a rotor of the electromotive drive. ### Claim 15 (depends on 1) The brake system as claimed in claim 1, wherein at least one third isolation valve is provided, said third isolation valve being disposed and configured in such a manner that, in a closed state of the third isolation valve, the first brake circuit is hydraulically decoupled from the first and the second pressure supply unit. ### Claim 16 (depends on 1) The brake system as claimed in claim 1, wherein the first hydraulic line and/or the second hydraulic line are (in each case) connected to a reservoir by way of a suction valve. ### Claim 17 (depends on 1) The brake system as claimed in claim 1, wherein an activation element, in particular a brake pedal, is disposed on the second pressure supply unit, wherein the second pressure supply unit comprises a master brake cylinder having a single piston that is activatable by means of the activation element. ### Claim 18 (depends on 1) A method for controlling a brake system, in particular a brake system as claimed in claim 1, said method comprising the steps: controlling a first pressure supply unit of a first module by means of a first control apparatus in a normal operation, controlling a multiplicity of brake pressure adjustment valves in a second module in a normal operation, detecting a first error event, in particular a partial failure of the second module, controlling the brake system in the first error event in such a manner that for providing an ABS braking operation and/or a yaw torque intervention a (wheel-individual and/or selective) adjustment of the pressures in the wheel brakes takes place while actuating at least one of the brake pressure adjustment valves of the second module and/or the, in particular bidirectional, isolation valves of the second module and the first pressure supply unit. ### Claim 19 (depends on 18) The method as claimed in claim 18, comprising: detecting a second error event, in particular a total failure of the third pressure supply unit, controlling the first pressure supply unit and at least two isolation valves of the first module in such a manner that, in the second error event, a brake circuit-individual pressure feedback control is implemented in the at least two brake circuits. ### Claim 20 (depends on 19) The method as claimed in claim 19, comprising: detecting a non-homogenous road condition, in particular a μ-split situation, controlling the first pressure supply unit in the second error event in such a manner that in non-homogenous road conditions that wheel brake of a selected brake circuit that has the coefficient of friction that is higher in comparison to the other wheel brake is utilized for determining a target brake pressure. ### Claim 21 (depends on 19) The method as claimed in claim 19, comprising: detecting a third error event, in particular a total failure of the third pressure supply unit and/or a failure of wheel sensors, controlling the first pressure supply unit in the third error event in such a manner that a 1-channel ABS is implemented, or in a fourth error event an intermittent brake is implemented by modulating the pressure between two predefined pressure levels in at least one of the brake circuits. ### Claim 22 (depends on 18) The method as claimed in claim 18, comprising: determining a first wheel blocking pressure on a first wheel brake which is assigned to one of the two brake circuits; determining a second wheel blocking pressure on a wheel brake which is assigned to the same brake circuit, wherein a non-homogenous road condition is detected when the first and the second wheel blocking pressure differ by more than 30 percent.