BRAKE SYSTEM ASSEMBLY

Description

[0001] The invention relates to an assembly of a braking system for a vehicle according to the type specified in the preamble of patent claim 1.

[0002] In addition to classic hydraulic brake systems, in which the brake pressure is generated via an externally operated brake pedal, electro-hydraulic external power brake systems and so-called brake-by-wire brake systems are also known.

[0003] With a hydraulic brake, the braking force is transmitted hydraulically. This means that a driver actuates a piston in the master cylinder using the brake pedal to feed brake fluid via lines and hoses to the wheel brakes and to build up braking pressure in the wheel brakes. The braking system can also include an electronically controlled driver assistance system, such as an ESC brake control module, which uses sensors to detect critical vehicle conditions and, by selectively braking individual wheels, ensures the driver control of the vehicle. The brake control module, also known as the brake control system, is usually positioned directly in front of the firewall in the direction of travel. However, it is also conceivable for it to be positioned more freely in the front of the vehicle, where it is connected to the master cylinder via fluid lines.

[0004] In an electro-hydraulic power-assisted braking system, the applied foot force acts merely as a control signal to activate the braking system. The hydraulic brake pressure for the wheel brakes is regulated by an electrical signal. A sensor detects a deflection of the brake pedal from its rest position, generating a control signal from this signal. A pressure supply device of a brake control module is activated to build up the brake pressure in the wheel brakes. The electro-hydraulic braking system is dependent on electrical energy and, in particular, features a hydraulic fallback function. In the event of a control unit failure, valves in the pressure supply device establish a direct connection between the master brake cylinder and the wheel brakes of an axle, so that braking force is generated by the driver's muscle power. This requires the brake control module to be mounted directly on the vehicle's firewall.

[0005] So-called "brake-by-wire" braking systems are becoming increasingly common, for example, in highly automated driving systems starting at Level 3, which allow the vehicle user to temporarily be relieved of driving responsibility and allow the vehicle to brake autonomously. Based on data and a multitude of vehicle sensors, a control unit activates a pressure supply device that builds up brake pressure in the brake circuits. Due to the dependence of this braking system on the functional reliability of the vehicle electronics, a fallback level is available that intervenes and builds up brake pressure if the normal level fails. For example, DE 10 2017 211 955 A1 describes a braking system specifically for a highly automated vehicle.

[0006] Due to the mechanical decoupling of the "Brake-By-Wire" braking system, the brake control modules of the respective normal and fallback levels no longer have to be mounted at a specific position in front of the driver directly on the vehicle's firewall, but can be positioned more freely and easily in the front-end package.

[0007] Typically, a brake control module of a braking system is pre-assembled with a holding device and then installed as an assembly in the vehicle. The brake control module is connected to the vehicle body via the holding device. If this holding device breaks at any point, e.g. on a holding arm, the brake control module's freedom of movement increases. The weight of the brake control module leads to increased loads on fluid connections and fluid lines. The excitations transmitted from the chassis can cause further damage, for example a break in the fluid lines or connections. This results in a loss of brake fluid and a loss of pressure in the wheel brakes. Technically, a break in the holding device is difficult to detect, which is why a vehicle can drive unnoticed for a long time with the broken holding device without it being detected or indicated by a vehicle system.However, this could potentially result in a total failure of the braking system. Braking systems are known from the prior art that are associated with a stop device that triggers an acoustic warning signal. For example, FR 371 537 A describes a positive connection device that connects a valve connected to a continuous brake line of railway trains or to another warning and / or indicator device, and a shaft controlled by levers that move past buffer stops or knockers mounted on the track, thereby activating the warning and / or indicator device.

[0008] CN 2 823 073 Y describes an opto-acoustic stop device for a braking system that prompts a vehicle user to check the braking system, particularly the brake pads. In a conventional braking system, the brake pedal may be depressed to its lowest point due to worn brake pads. The increased play of the depressed brake pedal creates contact with the stop device. This displaces a rear end cover of an insulating sleeve of the stop device such that a metal guide rod arranged in the insulating sleeve comes into contact with a metal cylinder. The metal cylinder is connected to an audible and light alarm that is triggered by the conductive connection established. US 2018 / 265062 A1 and US 2020 / 114894 A1 are also known from the prior art, which provide means for improving mounting on the vehicle frame.

[0009] The invention is based on the object of developing an assembly of a braking system of a vehicle according to the type specified in the preamble of patent claim 1 in such a way that a loss of bearing of the assembly can be quickly detected by means of simple, cost-effective and reliable means in order to largely prevent damage to the assembly.

[0010] This problem is solved by the characterizing features of patent claim 1 in conjunction with its preamble features.

[0011] The subclaims form advantageous developments of the invention.

[0012] In a known manner, an assembly of a particularly electrohydraulic braking system for a vehicle comprises at least one brake control module having an electronically controlled pressure supply device. The pressure supply device can, in particular, comprise a hydraulic block with a brake pressure control, an electric motor, and a pump. The brake control module can also be referred to as a brake control system.

[0013] When the assembly is installed, the pressure supply device is fluidly connected to at least one wheel brake of the vehicle. The pressure supply device is coupled to the wheel brake via fluid connections and fluid lines for a brake fluid. The pressure supply device is controlled by the electronic control unit based on data and a variety of different vehicle sensors to build up braking pressure in the wheel brake.

[0014] When the assembly is installed, the brake control module is connected to the vehicle body via a retaining device. The brake control module can, for example, have a housing that is screwed to the retaining device in multiple ways. The retaining device is connected to the vehicle body, for example, to a longitudinal member or a bulkhead that separates the engine compartment from the passenger compartment. The retaining device can, for example, be designed as a strip, a U-profile, a free-form part, or the like. It is conceivable for it to be made of metal or plastic.

[0015] According to the invention, the brake control module is connected to a mechanical stop device which, in the installed state of the assembly, is arranged at a distance from an adjacent vehicle component and, through interaction with the vehicle component, emits a warning signal in the event of a loss of bearing of the brake control module.

[0016] When the holding device is intact, the stop device has a defined distance from the adjacent vehicle component. The distance is predetermined in the vehicle's longitudinal direction, transverse direction and / or vertical direction. The defined distance is designed in such a way that in the event of a failure of the holding device, for example due to loosening and / or breakage at any point, the stop device interacts with the immediately adjacent vehicle component, in particular by repeatedly striking or impacting it, due to vibration-mechanical excitations of the chassis during driving, e.g. due to acceleration or deceleration, due to lateral dynamics such as cornering and / or when driving over speed bumps, potholes or the like, due to the amplified vibrations.The distance is designed based on the immediate surroundings of the assembly and takes vibration effects and tolerances into account. This ensures that if the bearings are lost, the stop device will hit the adjacent vehicle component early on. This allows the movement path of the brake control module to be limited.

[0017] Due to vibrational excitations, the mechanical interaction of the stop device with the adjacent vehicle component is repeated. The stop device acts as a resonator and, upon impact with the stop device, emits a repetitive acoustic signal that is transmitted into the passenger compartment, particularly via airborne and / or structure-borne sound. The stop device thus serves as a stop acoustic or sound source that triggers an indication or warning signal during driving that the component's bearings are loose. The stop device represents a control device that informs a vehicle user, using very simple and inexpensive means, that the retaining device is loose, defective, and / or broken.

[0018] Advantageously, the stop device provides a mechanically activated, acoustic warning signal without electronic displays, optical signals or the like, which warns of a permanent overload of the brake control module, the fluid lines and fluid connections, thereby reducing or largely avoiding damage to the brake system.

[0019] Preferably, the stop device is connected to the brake control module in a force-fitting, form-fitting, and / or material-fitting manner. The stop device can be screwed, clamped, welded, injected, and / or glued to the brake control module, among other things.

[0020] According to one embodiment, the stop device has at least one stop element. The stop element serves as a stop surface, i.e., as a physical obstacle or a point that, in the event of a loss of support, strikes or impacts a vehicle component, particularly one directly adjacent to it. The stop element can, for example, be designed as a bar that can be easily arranged on the brake control module at a predefined distance from the vehicle component.

[0021] Preferably, the stop element is made of a hard and / or solid material. The stop element is robust and has low damping and high transmission of the acoustic impulse. The stop element can be made of plastic and / or metal, for example. It can be designed as a metal strip, for example.

[0022] Preferably, the stop device is connected to a connecting element via which the brake control module is connected to the holding device. The brake control module is connected to the holding device with the interposition of a connecting element. This means that the stop device can be indirectly connected to the brake control module. The connecting element can serve, for example, as an adapter for connecting the brake control module to the holding device. For example, a stop element is formed on the connecting element and is arranged at a predetermined distance from the adjacent vehicle component, for example the vehicle body. If the holding device breaks or becomes loose, the stop element repeatedly strikes the adjacent vehicle component due to the vibration excitation of the vehicle and causes a knocking noise.

[0023] According to one embodiment, the brake control module is designed to build up wheel-individual brake pressures. The brake control module can be designed, for example, as an ESC unit, which can also be referred to as an ESP unit, of a conventional electro-hydraulic braking system that has an electronically controlled driver assistance system. The brake control module is mechanically or fluidly connected via the pressure supply device to a brake actuation unit of the vehicle, i.e. to a brake booster that can be actuated by a vehicle user via a brake pedal. The ESC unit only intervenes in a braking process if it detects a critical vehicle condition via sensors. The pressure supply device is then controlled via electronic signals in order to, for example, hydraulically operate only one brake caliper of a wheel brake without a pressure input from the master cylinder in order to thereby stabilize the vehicle.

[0024] Alternatively, it is conceivable that the brake control module is formed by integrating the ESC unit into the brake booster. This combination is referred to as an integrated brake control system or brake control module.

[0025] According to an alternative embodiment, the brake control module is designed as the first brake control module active during normal operation of a "brake-by-wire" braking system, which can also be referred to as the primary brake control module. This means that the first brake control module triggers a braking process of the vehicle depending on data from various vehicle sensors by controlling the pressure supply device to generate brake pressure in the wheel brakes. In the "brake-by-wire" design, the mechanical decoupling of an actuating device and a control device of the braking system allows for independent arrangement of the brake control module at any position in the vehicle package, thus allowing optimal use of vehicle installation space.

[0026] The stop device is preferably connected to a fluid reservoir of the first brake control module. In a brake-by-wire braking system, the first brake control module, which is active during normal operation, is fluidly connected to a fluid reservoir for brake fluid used to generate the brake pressure in the wheel brakes. A stop element can be formed, attached, or injected onto the fluid reservoir. If the retaining device is defective or the bearing of the assembly is lost, the stop element can repeatedly make contact with an adjacent vehicle component, for example due to vehicle acceleration, causing a knocking noise or warning signal.

[0027] According to a preferred embodiment, the vehicle component represents a redundant, second brake control module of the brake-by-wire braking system, also referred to as a secondary brake control module. This type of braking system provides a fallback level. This means that the assembly comprises a redundant, second brake control module that communicates with the first brake control module and takes over autonomous braking in the event of a malfunction of the first brake control module. The redundant second brake control module is installed, in particular, directly vertically below the first brake control module. The respective brake control modules are fluidically connected via fluid connections and fluid lines, on the one hand, to the fluid reservoir, and on the other hand, to the wheel brakes. A breakage or loosening of the retaining device causes the stop device to repeatedly strike the redundant second brake control module, triggering an acoustic warning signal.In particular, the stop device can repeatedly hit a housing, e.g. a metal housing of the redundant second brake control module.

[0028] The vehicle component is preferably designed as an element of the vehicle body. It is conceivable that the stop device is arranged at a defined distance, for example, from a strut tower, a side member, the bulkhead of the engine compartment, a connecting strut, or another part of the vehicle body. In the event of a loss of support of the assembly or a breakage of the retaining device, the brake control module has increased freedom of movement. Due to the deflection of the brake control module, the stop device repeatedly strikes or impacts the vehicle body. This is robustly designed and made primarily of metal, acting as a resonator. This successfully transmits the acoustic warning signal to the passenger compartment.

[0029] Further advantages and possible applications of the present invention will become apparent from the following description in conjunction with the embodiment shown in the drawing.

[0030] In the drawing: Fig. 1 is a perspective view of an assembly of a braking system known from the prior art, viewed obliquely from the front; and Fig. 2 is a side view of an assembly of a braking system according to the invention.

[0031] In Fig. 1 and Fig. 2 an assembly of a "Brake-By-Wire" braking system, designated overall by reference number 10, is shown in the installed state.

[0032] The assembly 10 comprises a first brake control module 12, which is fluidly connected to a fluid reservoir 14 for a brake fluid. The fluid reservoir 14 is installed, as is typical, above the first brake control module 12 in the vertical direction Z.

[0033] The assembly 10 comprises a second brake control module 16, which is arranged below the first brake control module 12 in the vehicle's vertical direction Z. The two brake control modules 12, 16 are connected to each other for communication. During normal operation of the "brake-by-wire" braking system, the first brake control module 12, also called the primary brake control module, actively builds up brake pressure in the braking system. The second brake control module 16, also called the secondary brake control module, forms a redundant fallback level that intervenes and builds up brake pressure if the first brake control module 12 fails.

[0034] The first brake control module 12 has a first housing 18, and the second brake control module 16 has a second housing 20. The housings 18, 20 are formed with fluid connections 22, to which fluid lines 24 are connected. The housings 18, 20 are fluidically connected, on the one hand, to the fluid reservoir 14 and, on the other hand, to brake circuits of the vehicle's wheel brakes (not shown here). To vent the brake system and reduce intake resistance, the brake control modules 12, 16 are arranged vertically beneath the fluid reservoir 14.

[0035] An electronic control unit (not shown here) is integrated into the housing 18 of the first brake control module 12. During normal operation of the braking system, this control unit controls a brake pressure controller (also not shown) located in the brake control module 12, which in turn controls an electromechanical actuator 26 of the brake control module 12 to pressurize the brake fluid in the brake circuits of the wheel brakes. The electronic control unit, the brake pressure controller, and / or the actuators 26 are arranged in particular in the first housing 18.

[0036] In the event of a failure of the first brake control module 12, the second brake control module 16 takes over the braking function. The second brake control module 16 also has an electronic control unit (not shown here) for controlling the brake pressure control device arranged in the brake control module 16, which in turn controls an actuator 28 to build up braking pressure. The electronic control unit, the brake pressure control device, and / or the actuator 28 of the second brake control module 16 are arranged in particular in the second housing 20.

[0037] In Fig. 1 and Fig. 2 The first brake control module 12 and the second brake control module 16, or their respective housings 18, 20, are connected to a vehicle body 32 via a holding device 30. The first brake control module 12 is, for example, screwed several times to the holding device 30, which in turn is connected to the vehicle body 32. The second brake control module 16 is supported on a longitudinal member 44 of the vehicle body 32 via its housing 20, with the holding device 30 interposed.

[0038] In Fig. 1 A failure of the holding device 30, for example due to a break at any point, is expressed by several lightning-shaped representations.

[0039] In Fig. 2The stop device 34 of the assembly 10 according to the invention is clearly visible. The stop device 34 is connected to the first brake control module 12. The stop device 34 serves to detect failure of the holding device 30 or to detect a loss of bearings in the assembly 10.

[0040] In this case, the stop device 34 is connected both indirectly and directly to the first brake control module 12. The stop device 34 has stop elements 36, 38. In the intact state of the holding device 30, the stop elements 36, 38 are at a defined distance from the vehicle body 32 in the vehicle longitudinal direction X, the vehicle transverse direction Y, and / or the vehicle vertical direction Z.

[0041] In the defective state of the holding device 30 or in the event of loss of bearing of the assembly 10, the stop device 34 is designed in such a way that at least one of the stop elements 36, 38 repeatedly strikes the vehicle body 32 due to the amplified vibrations of the first brake control module 12 in the vehicle longitudinal direction X, in the vehicle transverse direction Y and / or in the vehicle vertical direction Z, which serves, for example, as a resonance body. The mechanical interaction of the stop elements 36, 38 with the vehicle body 32 causes an acoustic disturbance, i.e. a mechanical, acoustic warning signal is emitted which is transmitted into the passenger compartment in particular via airborne sound and / or structure-borne sound. The stop elements 36, 38 are preferably made of metal and / or hard plastic so that the acoustic pulse penetrates the passenger compartment with as little attenuation as possible.

[0042] In the present case, the stop element 36 of the stop device 34 is, for example, materially connected to the fluid container 14. The stop element 36 is, for example, formed from plastic or injected as a metal element into the fluid container 14. In the vehicle's longitudinal direction X, it is arranged at a defined distance from a strut tower 40 of the vehicle body 32. In the event of failure of the holding device, the distance between the strut tower 40 and the stop element 36 is reduced, for example due to acceleration of the vehicle in the vehicle's longitudinal direction X, and the stop element 36 strikes or repeatedly impacts the strut tower 40.

[0043] The first brake control module 12 is connected to the holding device 30 via a connecting element 42. The stop element 38 is formed on the connecting element 42. It can be formed, for example, by a metal strip or the like. The stop element 38 is arranged at a predetermined distance in the vehicle longitudinal direction X from the vehicle body 32 and at a predetermined distance in the vehicle vertical direction Z from a connecting strut 46 of the vehicle body 32. If the holding device 30 breaks or becomes loose, the stop element 38 repeatedly strikes the vehicle body 32 and / or the connecting strut 46 due to the vibration excitation of the vehicle, causing a knocking noise.

Claims

1. Assembly (10) for a brake system of a vehicle, comprising at least one brake control module (12, 16) which has an electronically controlled pressure supply device which, in the installed state of the assembly (10), is fluidically coupled to at least one wheel brake of the vehicle, and wherein the brake control module (12, 16) is connected to a holding device (30) for arrangement on a vehicle body (32), characterized in that the brake control module (12, 16) has a mechanical stop device (34) which, in the installed state of the assembly (10), is spaced apart at a distance from an adjacent vehicle component and, by interaction with the vehicle component, outputs a warning signal in the event of a loss of support of the brake control module (12, 16).

2. Assembly according to claim 1, characterized in that the stop device (34) is connected to the brake control module (12, 16) in a force-fitting, form-fitting and / or integral manner.

3. Assembly according to any one of claims 1 or 2, characterized in that the stop device (34) has at least one stop element (36, 38).

4. Assembly according to claim 3, characterized in that the stop element (36, 38) is formed from a hard and / or solid material.

5. Assembly according to any one of claims 1 to 4, characterized in that the stop device (34) is arranged on a connecting element (40) via which the brake control module (12, 16) is connected to the holding device (30).

6. Assembly according to any one of claims 1 to 5, characterized in that the brake control module (12, 16) is designed to build up individual wheel brake pressures.

7. Assembly according to any one of claims 1 to 5, characterized in that the brake control module (12, 16) is designed as the first brake control module (12) which is active during normal operation of a brake-by-wire brake system.

8. Assembly according to claim 7, characterized in that the stop device (34) is connected to a fluid reservoir (14) of the first brake control module (12).

9. Assembly according to claim 7 or 8, characterized in that the vehicle component is designed as a redundant, second brake control module (16).

10. Assembly according to any one of claims 1 to 9, characterized in that the vehicle component is formed as an element of the vehicle body (32).