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DE-102024210865-A1 - Brake actuator for a vehicle's hydraulic braking system, axle brake module for a vehicle, and vehicle

DE102024210865A1DE 102024210865 A1DE102024210865 A1DE 102024210865A1DE-102024210865-A1

Abstract

The invention relates to a brake actuator (1) for a hydraulic brake system (11) of a vehicle, comprising: a pressure generating device (2) for providing an operating pressure for a hydraulic brake system (11); and an electric motor (3) that drives the pressure generating device (2) and has a plurality of electrical windings, wherein the electric motor (3) is configured to provide at least a predetermined backup braking power in the event of a fault condition of at least one of the plurality of electrical windings. The invention further relates to an axle brake module (10) for a vehicle with such a brake actuator (1) and to a vehicle with such an axle brake module (10).

Inventors

  • Ralf Kleemann
  • Bernd Hienz
  • Tobias Loss
  • Thorsten Maucher

Assignees

  • Robert Bosch Gesellschaft mit beschränkter Haftung

Dates

Publication Date
20260513
Application Date
20241113

Claims (10)

  1. Brake actuator (1) for a hydraulic brake system (11) of a vehicle, comprising: a pressure generating device (2) for providing an operating pressure for a hydraulic brake system (11); and an electric motor (3) which drives the pressure generating device (2) and has a plurality of electrical windings, wherein the electric motor (3) is configured to provide at least a predetermined backup braking power in the event of a fault condition of at least one of the plurality of electrical windings.
  2. brake actuator (1) after Claim 1 , wherein the multitude of electrical windings are each electronically coupled to a separate on-board power supply circuit.
  3. brake actuator (1) after Claim 1 or 2 , whereby the multitude of electrical windings can each be controlled via a separate electronic control unit.
  4. Brake actuator (1) according to one of the preceding claims, wherein the plurality of electrical windings are dimensioned such that a safety power of the electric motor (3) is at least as large as the predetermined backup braking power.
  5. Brake actuator (1) according to one of the preceding claims, wherein the pressure generating device (2) comprises a single piston-cylinder pressure unit.
  6. Brake actuator (1) according to one of the preceding claims, wherein the pressure generating device (2) comprises a single gear unit for transforming a rotary motion into a translational motion.
  7. Axle brake module (10) for a vehicle, comprising a hydraulic brake system (11) comprising two wheel brakes (12) of a common axle and a brake actuator (1) according to one of the preceding claims, wherein the brake actuator (1) is connected to the two wheel brakes (12).
  8. axle brake module after Claim 7 , wherein the hydraulic brake system (11) further comprises two inlet valves (IV) and two outlet valves (OV), each of which is assigned to the two wheel brakes (12), wherein the hydraulic brake system (11) is configured to regulate a brake pressure at the two wheel brakes (12) individually for each wheel by means of the two inlet valves (IV) and two outlet valves (OV).
  9. axle brake module after Claim 7 or 8 , wherein the hydraulic brake system (11) further comprises a refill valve (RVP).
  10. Vehicle, in particular motor vehicle, with at least one axle brake module (10) according to one of the Claims 7 until 9 .

Description

The invention relates to a brake actuator for a hydraulic braking system of a vehicle and to an axle brake module for a vehicle with such a brake actuator. The invention also relates to a vehicle, in particular a motor vehicle, with such an axle brake module. State of the art Modern vehicles are equipped with centralized braking system architectures. These are typically divided into Actuation (brake force amplification), Modulation (ESP), and Foundation (wheel brakes). In Actuation, the driver's pedal force is increased, for example, by electromechanical brake force amplification, while individual wheel pressure control is typically implemented in a second brake module (ESP). Newer systems also allow the driver to be decoupled when the system is functioning correctly, which can improve regenerative braking (brake blending) and pedal feel. However, such systems still provide a mechanical fallback in the event of a failure, thus mechanically or hydraulically connecting the driver to the wheel brakes. These systems are implemented as an integrated brake control unit or as two separate boxes. A distinction is also made between closed and open brake systems. In open brake systems, the outlet valves open in the event of an ABS failure, and brake fluid flows back into the reservoir. Additional brake fluid must be drawn in by means of the so-called replenishment, i.e. by closing certain valves in the hydraulic unit and retracting the plunger piston. In the future, so-called true-by-wire systems will become relevant, in which the driver's request is detected by an electrically connected brake pedal. Such systems have no mechanical fallback. Currently, centralized brake system architectures are used. The necessary redundancy is achieved through the use of... This is achieved either with a box featuring integrated redundancy or with two boxes, each with its own brake actuator, for example, a by-wire actuator (BWA) and an ESP. However, all four wheels of the vehicle are always supplied with brake pressure centrally. Instead of centralized architectures where all four wheels are connected to one or two central boxes, so-called by-wire axle modules can also be used. These generate the brake pressure for two wheels on each axle. This eliminates the need for long brake lines running from the engine compartment to the rear axle, offering flexibility in terms of wheelbase and manufacturing. Various layouts and redundancy concepts are known. For example, the DE 31 27 301 A1 For vehicles equipped with a 4-channel anti-lock braking system (ABS), a design for a traction control unit is presented. This unit, including the necessary safety devices for monitoring its function, enables a combined implementation of effective traction control and anti-lock braking system functionality with only minimal additional effort compared to a conventional ABS. The basic structure of a traction control unit integrated with the ABS is illustrated. The wheel speed sensors and brake pressure control valves of the driven vehicle wheels, along with the ABS return pump and the ABS signal input stage (which receives the wheel speed sensor output signals), are appropriately utilized within the traction control unit. The safety circuits of the ABS and the traction control unit are designed such that a malfunction in the ABS will deactivate the traction control unit, while a malfunction of the traction control unit will deactivate only the traction control unit. Furthermore, the DE 10 2005 035 834 A1 An electro-hydraulic unit for converting electrical into mechanical energy, comprising an electric motor with a stator and a rotor, comprising magnets or electrical windings that generate electromagnetic fields, at least one connection component for connecting the windings to at least one power supply, wherein the connection component extends through at least one through-hole, the through-hole being provided in a receiving body which accommodates electro-hydraulic valves and at least one piston pump gear-connected to the electric motor for supplying power to a slip-controlled braking system, and a rotor bearing comprising at least two spaced-apart rotor bearings, at least one of which is a so-called A-bearing supporting a shaft in the receiving body, and a so-called B-bearing which is supported in a cup-shaped motor housing. For improved bearing design, the core of the invention consists in the fact that the rotor is supported by the B-bearing on the motor housing by means of a rotationally fixed axle, bypassing the shaft. The DE 10 2018 133 189 A1 describes a braking system for a vehicle comprising the following components: - at least two hydraulic brake circuits, each with at least one hydraulically actuated wheel brake, - at least two Pressure supply devices (DV1, DV2), each comprising a piston-cylinder unit whose pistons are driven by an electric motor via a gearbox, in particular a spindle drive, -at least one valve arrangement with valves for individua