Description:Complete Specification:
The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed

Field of the invention

[0001] The present invention relates to the field of brake bedding.

[0002] Background of the invention

[0003] Brake bedding is a process of altering the surface of a brake pad or a brake disc (or both) to improve braking performance and smoothness. The bedding process is performed to form a transfer layer of brake pad friction material on the brake disc . The process is performed under controlled conditions with specific temperature and pressure. In assembly lines of vehicles, inertia wheels are used to perform brake bedding, wherein, the wheel is spun to a predefined speed and the brakes are applied and reapplied after a specific time interval.

[0004] Bedding of the vehicle brakes helps transfer an even layer of brake pad material onto the brake rotor which assists in smoother brake operation and improved braking power. In vehicles where new pads/rotors are installed, the drivers are advised to brake harder intentionally in safe areas so that the brakes are bedded and are ready for braking at full efficiency. In general, the brakes are not at its fullest potent for first 500Kms, (approximately 1000 brake stops).

[0005] The prior art US8991025 BB suggests A method for bedding a brake disc and/or pad includes monitoring the temperature of the brake disc and/or brake pad throughout the bedding process wherein the monitored temperature is utilized for adjusting the force of the brake pad on the brake disc including the steps of: raising the temperature of the brake pads and/or discs at a controlled rate to a desired bedding temperature; and maintaining the brake pads and/or discs at the bedding temperature. A machine for bedding a brake disc and/or pad is adapted to conduct the method by including at least one temperature sensor monitoring the temperature of a brake disc and/or brake pad throughout the bedding process. The machine regulates the speed of the motor, the pressure of the caliper, or a combination thereof, based on the temperature monitored by the temperature sensors. The same focuses on precise temperature control.

[0006] In the present invention, bedding techniques are described that may be performed during end of assembly line of the vehicle. The invention also describes an active and passive bedding process, said active and passive bedding being performed by the controller, when a brand new vehicle is with the costumer/driver.

[0007] To perform brake bedding, the present invention can be implemented in the end of the line production facility. In that stage, vehicle may be placed over the roller bench. The drive torque & brake torque may be controlled by a controller for a specific number of cycles (for example 30 cycles), the vehicle wheel speed may be increased to a specified upper limit (for example 70Km/h) & then braked to another specified lower limit (for example 10 Km/hr).

[0008] The present invention also discloses an active bedding process wherein for the first pre-defined number of braking (example first 1000 brakes applied by the driver) a brake pre-fill with a pressure equivalent of approximately 5 bar may be provided to brake the wheels until approximately 1000 stops (as an example). Alternatively, the invention also discloses a passive brake bedding process. In passive braking, for the first 1000 braking (as an example) the electronic stability program (ESP) may sense the braking request from the driver and provide extra pressure in addition to the driver requested pressure to the system to stop the vehicle at the intended distance.

[0009] Brief description of the accompanying drawings
[0010] An embodiment of the invention is described with reference to the following accompanying drawings:
[0011] Figure 1 depicts a controller (1) to facilitate bedding of a brake assembly (4) in a braking system of a vehicle.
[0012] Figure 2 depicts a flowchart for a method to facilitate bedding of a brake assembly (4) in a braking system of a vehicle.

[0013] Detailed description of the drawings:

[0014] The present invention will now be described by way of example, with reference to accompanying drawings. Throughout all the figures, same or corresponding elements may generally be indicated by same reference numerals. These depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the figures are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations, and fragmentary views. In predetermined instances, details which are not necessary for an understanding of the present invention, or which render other details difficult to perceive may have been omitted.

[0015] Referring to Figure 1, the same discloses a controller (1) to facilitate bedding of a brake assembly (4) in a braking system(6) of a vehicle. The brake assembly (4) comprises a brake pad (2) coupled to a brake disc (3) . Said controller (1) is adapted to operably control the braking system(6).

[0016] The controller (1) may be a computing system with an associated memory. The controller (1) may be any computer, controller, or other like device capable of controlling the bedding process at an end of assembly line. The controller (1) may be a vehicle electric control unit (ECU) capable of controlling the brake pressure in the braking system of a vehicle. The controller (1) maybe a single unit or a combination of multi-computing systems and sensors. The controller (1) may be in communication with the braking system of the vehicle, wherein, the controller (1) maybe adapted to control opening and closing of valves in a brake circuit (5) of the braking system(6) so as to control the transfer of a brake pressure to the brake assembly (4) through a brake fluid.

[0017] The controller (1) may be adapted to control the speed of a motor associated with a powertrain of the vehicle. The controller (1) may be in communication with sensors such as temperature sensors, pressure sensor, wheel speed sensors accelerometers and the like.
[0018] Said controller (1) is adapted to detect a speed of the vehicle. According to an embodiment, the controller (1) may receive a speed information from a speed sensor. Said controller (1) is adapted to transmit a brake pressure to the brake assembly (4) when the speed reaches an upper-threshold speed. In an example, this upper-threshold speed may be experimentally derived considering vehicle safety and driver comfort.
[0019] The controller (1) is further adapted to stop the transmission of the brake pressure when the speed reaches a lower-threshold speed and restart the transmission the brake pressure when said detected speed reaches the upper-threshold speed after a pre-defined time.
[0020] The controller (1) restarts the transmission the brake pressure for an N number of instances, said N number of instances determined based on at least one property of the brake assembly (4). This property maybe the kind/shape material of brake pad (2)/brake disc (3), the temperature recorded during bedding process, the speed of the vehicle and the like.
[0021] In an example, where the vehicle runs the first 300 kms with new pad/rotor, the braking force is not at its fullest efficiency, as the pad to rotor contact does not happen completely. During this time, the driver must provide some extra effort to stop the vehicle than the required effort. If the driver did hard braking during the first N brakes (say1000 brakes), this might lead to DTV (Disc thickness variations) and leads to lower efficiency by of braking and judder noisex. To solve this problem, the disclosed technique can be implemented. In an example, the vehicle may be placed on a roller bench at the end of an assembly line. The controller (1) will control the drive torque & brake torque. For the first N cycles (say 30) the vehicle wheel speed is increased to the upper threshold speed (say 70Km/h) and braked to a lower threshold speed say (10 Km/hr). In this example, the input signals may be Master cylinder pressure, the Wheel speed and the Brake light switch and the output may be the brake pressure demand. The present invention may be activated automatically or through manually through an HMI interaction with the user/driver.
[0022] Active brake bedding technique is now disclosed further. This active brake bedding technique is hereby referred to as a first bedding. Said brake system (6) comprises with an emergency brake assist functionality (known) to facilitate the first bedding of the brake assembly (4). Typically, in an emergency brake assist function, the braking system for an emergency stop by pre-filling the circuit with fluid such that the linings are just in contact with the discs.

[0023] Said controller (1) is adapted to transmit a brake fluid as a brake-prefill in the braking system when the vehicle speed reaches the upper threshold speed. The controller (1) transmits the brake fluid as the brake-prefill for said N number of instances. In a working example, during first 1000 stops, when the vehicle speed > 60Km/h, the controller (1) may provide a brake prefill with the pressure equivalent ~5bar to the wheel brakes. The controller (1) may also provide warning to driver when the driver drives vehicle at a speed greater than 80Km/h to prevent hard braking.

[0024] Passive brake bedding technique is now disclosed further. This passive brake bedding technique is hereby referred to as a second bedding. To facilitate a second bedding of the brake assembly (4), said controller (1) is adapted to provide an additional brake pressure over a driver-requested brake pressure for said N number of instances. According to an embodiment, the controller (1) transmits a warning to the driver when facilitation of said first and passive second is enabled by the controller (1).

[0025] In a working example, the electronic stability program (ESP ) of the vehicle senses the braking request from the driver and provides extra pressure in addition to the driver requested pressure to the system to stop the vehicle at the intended distance. For instance, during first 1000 stops, brake assistance provided by the controller (1) to the braking system by adding 5-10 bar to the driver’s request that gradually reduces as the number of stops increases (as the pad to rotor contact increases).
[0026] Further, additional warning may be provided to driver when the driver drives vehicle speed greater than an upper threshold speed (say 80Km/h) to prevent hard braking.
[0027] Referring to Figure 2, the same discloses a flowchart for a method to facilitate bedding of a brake assembly (4) in a braking system of a vehicle. The method (100) to facilitate bedding of a brake assembly (4) by a controller (1) in a braking system of a vehicle is implemented by the system as described in Figure 1. The brake assembly (4) comprises a brake pad (2) coupled to a brake disc (3), said controller (1) adapted to operably control the braking system. The method(100) comprises the first step (101) of detecting by the controller (1), a speed of the vehicle. This is followed by the second step (102) of transmitting , by the controller (1), a brake pressure to the brake assembly (4) when the speed reaches an upper-threshold speed. This is followed by the step (103) of stopping , by the controller (1), the transmission of the brake pressure when the speed reaches a lower-threshold speed. The next step (104) is restarting, by the controller (1), the transmission the brake pressure for an N number of instances, when said detected speed reaches the upper-threshold speed after a pre-defined time.
[0028] According to an embodiment, the brake system (6) comprises with an emergency brake assist functionality to facilitate a first bedding of the brake assembly (4). In that, a brake fluid is transmitted by the controller (1), as a brake-prefill in the braking system when the vehicle speed reaches the upper threshold speed.

[0029] To facilitate a second bedding of the brake assembly (4), the method comprising the step of providing by the controller (1), an additional brake pressure over a driver-requested brake pressure for said N number of instances, said N number of instances determined based on at least one property of the brake assembly (4).

[0030] In an example, where the vehicle runs the first 300 kms with new pad/rotor, the braking force is not at its fullest efficiency, as the pad to rotor contact does not happen completely. During this times, the driver must provide some extra effort to stop the vehicle than the required one. If the driver did hard braking during the first N brakes (say1000 brakes), this might lead to DTV (Disc thickness variations) and causes to lower efficiency by of braking and even leads to judder noise. To solve this problem, the disclosed technique can be implemented. In an example, the vehicle may be placed on a roller bench at the end of an assembly line. The controller (1) will control the drive torque & brake torque. For the first N cycles (say 30) the vehicle wheel speed is increased to the upper threshold speed (say 70Km/h) and braked to a lower threshold speed say (10 Km/hr). In this example, the input signals may be Master cylinder pressure, the Wheel speed and the Brake light switch and the output may be the brake pressure demand. The present invention may be activated automatically or through manually through an HMI interaction with the user/driver.
[0031] In a working example for the first bedding (active bedding), during first 1000 stops, when the vehicle speed is greater than 60Km/h, the controller (1) may provide a brake prefill with the pressure equivalent ~5bar to the wheel brakes. The controller (1) may also provide warning to driver when the driver drives vehicle at a speed greater than 80Km/h to prevent hard braking.
[0032] In a working example for second bedding (passive bedding), the electronic stability program (ESP ) of the vehicle senses the braking request from the driver and provides extra pressure in addition to the driver requested pressure to the system to stop the vehicle at the intended distance. For instance, during first 1000 stops, brake assistance provided by the controller (1) to the braking system by altering the DBR by adding 5-10 bar to the driver’s request that gradually reduces as the number of stops increases (as the pad to rotor contact increases).
, Claims:We Claim:
1. A controller (1) to facilitate bedding of a brake assembly (4) in a braking system of a vehicle, the brake assembly (4) comprising a brake pad (2) coupled to a brake disc (3), said controller (1) adapted to operably control the braking system,

characterized in that, said controller (1) adapted to:

-detect a speed of the vehicle,
-transmit a brake pressure to the brake assembly (4) when the speed reaches an upper-threshold speed,
-stop the transmission of the brake pressure when the speed reaches a lower-threshold speed, and
-restart the transmission the brake pressure when said detected speed reaches the upper-threshold speed after a pre-defined time.

2. The controller (1) as claimed in Claim 1, wherein, the controller (1) restarts the transmission the brake pressure for an N number of instances, said N number of instances determined based on at least one property of the brake assembly (4).

3. The controller (1) as claimed in Claim 1, said brake system (6) comprises with an emergency brake assist functionality to facilitate a first bedding of the brake assembly (4), said controller (1) is adapted to:
-transmit a brake fluid as a brake-prefill in the braking system when the vehicle speed reaches the upper threshold speed.

4. The controller (1) as claimed in Claim 3, wherein, the controller (1) transmits the brake fluid as the brake-prefill for said N number of instances.

5. The controller (1) as claimed in Claim 3, wherein, to facilitate a second bedding of the brake assembly (4), said controller (1) is adapted to:
-provide an additional brake pressure over a driver-requested brake pressure for said N number of instances.

6. The controller (1) as claimed in Claim 5, wherein, the controller (1) transmits a warning to the driver when facilitation of said first and second bedding is enabled by the controller (1).

7. A method (100) to facilitate bedding of a brake assembly (4), by a controller (1) in a braking system of a vehicle, the brake assembly (4) comprising a brake pad (2) coupled to a brake disc (3), said controller (1) adapted to operably control the braking system,

characterized in that method, the following steps of:
- detecting by the controller (1), a speed of the vehicle (101),
-transmitting , by the controller (1), a brake pressure to the brake assembly (4) when the speed reaches an upper-threshold speed (102),
-stopping , by the controller (1), the transmission of the brake pressure when the speed reaches a lower-threshold speed (103),
-restarting, by the controller (1), the transmission the brake pressure for an N number of instances, when said detected speed reaches the upper-threshold speed after a pre-defined time (104).

8. The method (100) as claimed in Claim 7, said brake system (6) comprises with an emergency brake assist functionality to facilitate a first bedding of the brake assembly (4), wherein transmitting a brake fluid, by the controller (1), as a brake-prefill in the braking system when the vehicle speed reaches the upper threshold speed.

9. The method (100) as claimed in Claim 8, wherein, to facilitate a second bedding of the brake assembly (4), the method comprises the step of:
-providing by the controller (1), an additional brake pressure over a driver-requested brake pressure for said N number of instances, said N number of instances determined based on at least one property of the brake assembly (4).