Brake system of a vehicle, method for operating a vehicle and two-wheeled vehicle

Abstract

The invention relates to a brake system (20) of a vehicle (10), having a detection device (21) which is designed to detect a deceleration request (80) of the vehicle in at least two ranges, and an electric machine (30) which is connected to a control unit (23) of the brake system (20) in a manner such that a value of a braking moment (83) can be provided to the electric machine (30) by the control unit (23), wherein the control unit (23) is designed to provide the value on the basis of the detected range of the at least two ranges of the deceleration request (80), and furthermore the electric machine (30) is coupled (42) to a drive wheel (41) of the vehicle in a torque-transmitting manner in such a manner that the provided value (83) can be transferred to the drive wheel (41) as a braking moment (90).

Description

[0001] Description

[0002] title

[0003] Braking system of a vehicle, method for operating a vehicle and two-wheeler

[0004] State of the art

[0005] The invention is based on a braking system of a vehicle according to the class of the independent claim. The present invention also relates to a two-wheeler and a method for operating such a vehicle.

[0006] A two-wheeler, particularly a motorcycle, usually has two hydraulic brake circuits that are designed independently of one another. A first brake circuit of the two hydraulic brake circuits is connected to a front wheel of the two-wheeler, and a second brake circuit of the two hydraulic brake circuits is connected to a rear wheel of the two-wheeler. With such a second hydraulic brake circuit, a rider of the two-wheeler can, for example, operate a brake lever or a brake pedal that is operatively connected to a brake on the rear wheel, and hydraulic brake pressure is built up that presses a brake pad against a friction surface that is connected to the rear wheel, thus exerting a braking moment on the rear wheel. Furthermore, a rider of the two-wheeler can, for example,Now operate a brake lever that is operatively connected to a brake on the front wheel, and hydraulic brake pressure is built up, pressing a brake pad against a friction surface connected to the front wheel, thus exerting a braking moment on the front wheel. Both of these processes can be supported by assistance systems, such as an anti-lock braking system, which can regulate the hydraulic brake pressure on the brake pad.

[0007] There are also two-wheelers in which an internal combustion engine is supported by an electric motor mounted on the drive wheel, or even completely replaced. An electric motor can also be operated as a generator, meaning it absorbs mechanical power, converts it into electrical energy, and stores it in the two-wheeler's battery. This is commonly known as recuperation and also creates a braking torque that can be used to slow the two-wheeler.

[0008] EP 1 855 219 B1 describes a system which, when a brake lever is operated, requests a recuperation torque from the electric motor on the rear wheel in addition to the hydraulically induced braking torque on the front wheel and thus brakes the two-wheeler.

[0009] Disclosure of the invention

[0010] A braking system of a vehicle having the features of the independent claim offers the advantage that it is possible to adapt a braking torque to a desired deceleration requirement of the vehicle and that such torque can be transmitted directly to a drive wheel via an electric machine.

[0011] For this purpose, a braking system of a vehicle, in particular a two-wheeler, is provided. The braking system comprises a detection device configured to detect a deceleration request of the vehicle in at least two ranges.

[0012] Furthermore, an electric machine is connected to a control unit of the braking system in such a way that a value of a braking torque can be provided to the electric machine by the control unit. The control unit is further configured to provide such a value based on the detected range of the at least two ranges of the deceleration request.

[0013] The electric machine is coupled to a drive wheel of the vehicle in a torque-transmitting manner, and the value of the braking torque can be transferred to the drive wheel by the electric machine as a braking torque.

[0014] The measures listed in the dependent claims enable advantageous refinements and improvements of the device specified in the independent claim. It should be noted that the electric machine can, for example, be an electric motor designed to drive the vehicle and can be operated as a generator. It should be noted here that generator operation is characterized by the electric machine being able to absorb power, convert it into electrical energy, and store it in the vehicle's battery.

[0015] This process is also called recuperation. However, designs are also conceivable in which the electric motor can only operate as a generator.

[0016] A deceleration request can be understood as a driver input to reduce the vehicle's current speed while driving or to apply a braking torque to the drive wheel. The driver input can, for example, be the actuation of a lever, button, or rotary handle. The detection device is designed to detect this input, whereby the driver input can vary, for example, in an actuation force or an actuation travel. The detection device is designed, for example, to detect at least two forces of different magnitudes or two travels of different lengths.

[0017] A torque-transmitting coupling is a physical connection between the drive wheel and the electric machine, designed to transmit torque between the drive wheel and the electric machine. This can be, for example, a chain, a belt, or a common axis of rotation of the two aforementioned components.

[0018] It is expedient if the control unit or the detection device is designed to assign a first deceleration request to a first area of ​​the at least two areas and to assign a second deceleration request to a second area of ​​the at least two areas. In this case, the first deceleration request is smaller in magnitude than the second deceleration request. Furthermore, the control unit is designed to assign a first value of a first braking torque to the first area and a second value of a second braking torque to the second area. In this case, the first value is smaller in magnitude than the second value. Overall, this offers the advantage that deceleration requests that differ from one another in terms of their magnitude, i.e. are therefore different, can be assigned different braking torques.For example, the driver can request a deceleration in a first braking maneuver at a first speed that is greater in magnitude than another deceleration request in a second braking maneuver at a second speed. For example, a driver will request a smaller deceleration for a deceleration from 110 km / h to 100 km / h that is to occur within 5 seconds than for a deceleration from 110 km / h to 0 km / h, which is also to occur within 5 seconds.

[0019] It is advantageous if another wheel of the vehicle is operatively connected to a brake of the vehicle, wherein the brake is configured to decelerate the other wheel. The control unit is configured to provide a third value of a braking torque upon detection of a deceleration request in a third range. This third value can be transmitted to the other wheel as an additional braking torque via the brake. This has the advantage that a higher braking force can be transmitted through two wheels than through one.

[0020] For example, this can be achieved by the control unit causing the brake to build up hydraulic pressure, wherein the brake is designed in particular to generate such hydraulic pressure. In a further embodiment, the hydraulic pressure could be provided by an anti-lock braking system. Embodiments are also conceivable in which the brake is operated electrically and is controlled electrically by the control unit. The deceleration of a vehicle is limited by a frictional force that can be transferred to a surface by means of the tires. In this embodiment, an overall higher braking effect could be achieved by braking the other wheel of the vehicle than if only the drive wheel were braked by means of the electric motor, since two wheels now transfer the frictional force.This can be particularly advantageous in dynamically changing driving situations when the transferable friction force changes, for example when changing from straight-ahead driving to cornering.

[0021] In particular, it would be advantageous if the control unit were configured to provide the third value as the difference between a fifth value and a fourth value. The fourth value is selected as a specific value of the braking torque at the drive wheel. The control unit or the detection device is configured to assign a third deceleration request to the third range, and the control unit is further configured to assign the fifth value of a fifth braking torque to the third range. This fifth value is greater in magnitude than the fourth value.

[0022] This allows, for example, the vehicle to be braked even if the driver misjudges the transferable friction force at the wheel driven by the electric motor and does not actively apply the brake. In this case, total deceleration is implemented by a braking moment at the rear wheel and a braking moment at the front wheel, even if the driver only requests deceleration via the rear wheel's detection unit. Further examples of applications could include the braking moments being distributed to both wheels, adapted to the road surface, if the braking force transferable to the road surface is reduced due to its properties, such as wetness, slipperiness, or dirt.

[0023] It may also be expedient if the fourth value of the braking torque at the drive wheel is selected as at least 60% of the maximum braking power of the electric motor, preferably at least 80%, and in particular the maximum braking power of the electric motor. In this configuration, the brake would transmit a braking torque even if the maximum braking torque transmittable by the electric motor has not yet been transmitted. This would provide a safety reserve, and the rear wheel could be further braked should the driver request further deceleration.

[0024] It may be expedient if the brake is designed as a hydraulic, mechanical, or electric brake. The embodiment described above allows a brake design that is independent of the design using the electric machine. This can be economically advantageous; moreover, a second brake that is independent of the first offers greater road safety. Furthermore, the brake can be designed as a further electric machine that is designed to transfer a braking torque to the further wheel. This can be advantageous if a further electric machine is already provided for the further wheel. A control strategy for the electric machine according to claim 1 can be transferred to the further electric machine, and a hydraulic brake can be omitted. This simplifies the system and would also be advantageous from an economic point of view.

[0025] It would be expedient if the detection device were designed as a pressure sensor, displacement sensor, or angle sensor, which is configured to detect pressure, displacement, or angle in at least two areas, and if the detection device comprised a lever, pedal, or button. This would allow for a practical and ergonomically favorable design depending on the vehicle type.

[0026] Furthermore, it may be advantageous if the control unit is connected to another control unit in such a way that the deceleration request is provided by the control unit to the control unit. A further control unit could, for example, be another assistance system, autopilot, distance control system, or traffic sign recognition with automatic cruise control. This additional control unit can then issue deceleration requests independent of the driver, thus increasing the road safety of the two-wheeler or assisting the driver in driving situations that they misjudged.

[0027] A practical embodiment would be to integrate the braking system into a two-wheeler, with a control unit integrated into another system of the two-wheeler, such as an anti-lock braking system. This embodiment allows the functionality of the anti-lock braking system to be used to build up braking pressure on the wheel not braked by the electric motor. Furthermore, the control logic of the anti-lock braking system can be used to distribute the braking torque between the two wheels according to the driving situation, thus ensuring safe braking. A two-wheeler can be, for example, a motorcycle. Brief description of the drawings

[0028] Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description.

[0029] Figure 1 shows an embodiment of a vehicle according to the invention.

[0030] Figure 2 shows a description of a functional sequence according to the invention.

[0031] Figure 1 schematically shows a vehicle 10 designed as a two-wheeler 11 with a braking system 20, an electric machine 30, a rear wheel 40 and a front wheel 50. The braking system 20 comprises a detection device 21 which is connected to a control unit 23. The control unit 23 is connected to the electric machine 30. The electric machine 30 is connected to the rear wheel 40 in a torque-transmitting manner, for example via a chain 421, a belt 422 or directly to the rotational axis of the motor. The rear wheel 40 is thus designed as a drive wheel 41. If the detection device 21 is actuated, this is detected as a deceleration request and forwarded by the control unit 23 to the electric machine 30 as the value of a braking torque.If the braking torque cannot be fully transmitted to the rear wheel 40, this is detected by control unit 23 via connection 24, and a third braking torque value is provided by control unit 23. This value is transmitted to a brake 70 via connection 25. The detection device can be, for example, a lever 211, a button 212, or a pedal 213.

[0032] Figure 1 also shows a front wheel 50, which is operatively connected to a brake 70 and a brake lever 71, which is connected to the brake 70 via a brake line 72. The brake 70 can be a hydraulic brake 701, in which case the brake line 72 is a hydraulic line 721. Furthermore, it can also be a mechanical brake 702, in which case the brake line 72 is a cable pull 722, or an electric brake 703, in which case the brake line 72 is an electrical connection 723. In the described embodiments, the brake 70 can be a friction brake, which means that a friction lining 730 is pressed against a friction surface 731, for example a brake disc 732 on the front wheel 50. Figure 1 also shows a further control unit 60, which is connected to the first control unit 23. Furthermore, the control unit 23 is connected to the electric machine 30 independently of the detection device 21.The brake 70 is connected to the control unit 23 independently of the brake lever 17. The control unit 60 is configured to provide a deceleration request to the control unit 23. This may be the case, for example, if the control unit 60 is part of a distance control system 601 and / or a cruise control system 602 and / or an autopilot 603.

[0033] Alternatively, although not shown in the figures, brake 70 can also be an electric motor. Brake lever 71 is then another sensing element with the same functionality as sensing element 21.

[0034] Figure 2 shows a schematic representation of a possible sequence of a method according to the invention.

[0035] A deceleration request 80 or 801, which was detected by the detection device 21, is provided to the control unit 23. The control unit 23 provides the electric machine 30 with a value of a braking torque 83. The electric machine 30 transmits this braking torque 90 to the rear wheel 40. The control unit 23 is provided with a value of a transmittable torque by the electric machine 84. This value 84 indicates the magnitude of the braking torque that can be transmitted by the electric machine to the rear wheel 40. If, for example, the value of a braking torque 83 is greater than the value of the transmittable torque 84, this difference can be provided to the brake 70 as the value of an additional braking torque 85. This value is then transmitted by the brake 70 as a braking torque 91 to the front wheel 50.

[0036] Furthermore, the value of the braking torque 85 can also be provided by the control unit 23, for example, to shorten a braking distance or improve the overall braking effect, should the road surface be such that the entire value of the braking torque 83 cannot be completely transmitted to the rear wheel 40 by the electric machine 30 for safety reasons. This can be the case in wet and / or slippery conditions and / or dirt, which ensure that only a reduced braking torque 90 can be transmitted to the rear wheel.

[0037] Control unit 23 is thus designed to divide a deceleration request 80 and / or 82 into a value of a braking torque 83 and / or 85.

[0038] Furthermore, a deceleration request 82 provided by the control unit 60 can be transmitted to the control unit 23. This deceleration request 82 can also be divided by the control unit 23 into values ​​of a braking torque 83 and / or 85.

[0039] Furthermore, the deceleration requests 80 and 82 can also be added together and divided by the control unit 23 into values ​​of a braking torque 83 and / or 85.

Claims

1. A braking system (20) of a vehicle (10), in particular a two-wheeler (11), comprising a detection device (21) configured to detect a deceleration request (80) of the vehicle in at least two ranges, and an electric machine (30) connected to a control unit (23) of the braking system (20) in such a way that a value of a braking torque (83) can be provided to the electric machine (30) by the control unit (23), wherein the control unit (23) is configured to provide the value based on the detected range of the at least two ranges of the deceleration request (80), and furthermore, the electric machine (30) is coupled (42) to a drive wheel (41) of the vehicle in a torque-transmitting manner in such a way that the provided value (83) can be transmitted to the drive wheel (41) as a braking torque (90).

2. Braking system according to claim 1, characterized in that the control unit (23) or the detection device (21) is designed to assign a first deceleration request (80) to a first area of ​​the at least two areas and to assign a second deceleration request (801) to a second area of ​​the at least two areas, wherein the first deceleration request (80) is smaller in magnitude than the second deceleration request (801), and the control unit (23) is further designed to assign a first value of a first braking torque (83) to the first area and to assign a second value of a second braking torque (831) to the second area. where the first value is smaller than the second value 3. Braking system according to claim 1 or 2, characterized in that a further wheel (51) of the vehicle is operatively connected to a brake (70) of the vehicle, wherein the brake (70) is designed to decelerate the further wheel, wherein the control unit (23) is designed to provide a third value of a braking torque (85) upon detection of a deceleration request in a third range (802), and the provided third value (85) can be transmitted to the further wheel (51) by means of the brake as a further braking torque (91).

4. Braking system according to claim 3, wherein the control unit (23) is designed to provide the third value (85) as the difference between a fifth value and a fourth value, the fourth value being selected as a specific value of the braking torque (90) on the drive wheel (50), and the control unit (23) or the detection device (21) is designed to assign a third deceleration request (802) to the third range, and the control unit (23) is further designed to assign the fifth value of a fifth braking torque to the third range, the fifth value being greater in magnitude than the fourth value.

5. Braking system according to the preceding claim 4, characterized in that the fourth value is selected as the specific value of the braking torque on the drive wheel (41) as at least 60% of the maximum braking power of the electric machine, preferably at least 80%, and in particular the maximum braking power of the electric machine (30) is selected 6. Braking system according to claim 3 to 5, wherein the brake (70) is designed as a hydraulic (701), mechanical (702) or electric brake (703).

7. Braking system according to claim 3 to 5, according to which the brake (70) is designed as a further electric machine which is designed to transmit a braking torque to the further wheel.

8. Brake system according to claims 1 to 7, wherein the detection device (21) is designed as a pressure sensor, displacement sensor or angle sensor, wherein the pressure sensor is designed to detect a pressure in at least two areas, the displacement sensor a displacement in at least two areas and the angle sensor an angle in at least two areas.

9. A braking system according to claim 1 to 8, wherein the detecting device comprises a lever (211), button (212), or pedal (213).

10. Braking system according to claims 1 to 9, wherein the control unit (23) is connected to a further control unit (60) in such a way that a further deceleration request (82) can be provided by the further control unit (60) of the control unit (23).

11. A method for operating a vehicle (10), in particular a two-wheeler (11), with a detection device (21) which detects a deceleration request (80) of the vehicle in at least two areas, and an electric machine (30) which is connected to a control unit (23) of the braking system (20) in such a way that the control unit (23) of the electric machine (30) provides a value of a braking torque (83), wherein the control unit (23) provides the value on the basis of the detected deceleration request (80), and further, the electric machine (30) is coupled to a drive wheel (41) of the vehicle in such a way that the provided value (83) is transmitted to the drive wheel (41) as a braking torque (90).

12. Two-wheeler (11) with a braking system according to one of the preceding claims 1 to 10.

13. Two-wheeler according to claim 12, wherein the control unit (23) is integrated into an anti-lock braking system (231).

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