A method of rust removal from a brake disc

Abstract

This solution relates to a brake disc rust removal method to address the problem in existing technologies where brake disc rust removal occurs during energy recovery, thus affecting energy recovery performance under low deceleration requirements and vehicle braking performance. The brake disc rust removal method includes: during vehicle operation, when the vehicle condition is determined to meet preset rust removal conditions, actively controlling a hydraulic cylinder to cyclically drive the brake pads to wipe and remove rust from the brake disc using a first rust removal hydraulic pressure and a first rust removal duration, until the vehicle condition changes to the point where the preset rust removal conditions are no longer met.

Description

Technical Field

[0001] This invention relates to the field of brake disc rust removal, specifically a method for removing rust from brake discs. Background Technology

[0002] In fuel-powered vehicles, rust removal of the brake discs is usually achieved by the friction between the brake pads and the brake disc when the driver presses the brake pedal.

[0003] As more and more electric vehicles are introduced to the market, new features related to electric vehicles are constantly being developed. Energy recovery, a feature unique to electric vehicles, can convert the kinetic energy that would otherwise be lost by the brake discs into electrical energy via the motor and store it in the battery during braking, thus increasing the vehicle's driving range.

[0004] Electric vehicles still use the method of removing rust from the brake discs when the driver presses the brake pedal. However, vehicles with energy recovery functions generally have the problem of brake disc corrosion not being removed in a timely and effective manner. The reason is that since the vehicle uses energy recovery to decelerate during braking, the braking force of the mechanical hydraulic braking system is very small during energy recovery. This results in a very small force exerted by the brake pads on the brake disc, which means that the rust on the brake disc cannot be effectively removed. Therefore, after prolonged use, the brake disc is prone to rust. When the vehicle actually needs the brake disc to intervene, the rusted brake disc cannot provide the necessary braking performance, which poses a safety hazard. Furthermore, removing rust from the brake disc during energy recovery means that a very small portion of the vehicle's kinetic energy is allocated to the mechanical hydraulic braking system, thus affecting the vehicle's energy recovery performance. Summary of the Invention

[0005] Based on the above situation, this invention designs a brake disc rust removal method to solve the problem that in the prior art, brake disc rust removal occurs during the energy recovery process, which affects the energy recovery performance under low deceleration requirements and the vehicle's braking performance.

[0006] The technical solution of this invention is as follows:

[0007] This invention provides a method for removing rust from brake discs, comprising:

[0008] During vehicle operation, when the vehicle condition is determined to meet the preset rust removal conditions, the hydraulic cylinder is actively controlled to cycle through the brake pads to wipe and remove rust from the brake disc with the first rust removal hydraulic pressure and the first rust removal duration, until the vehicle condition changes to no longer meet the preset rust removal conditions.

[0009] Preferably, the vehicle status meets the preset rust removal conditions as follows: the amount of brake disc corrosion obtained at the current calculation time reaches the preset brake disc corrosion threshold, the pre-calibrated functions related to vehicle stability are not activated, and the vehicle speed is within the preset speed range.

[0010] The first rust removal hydraulic pressure and the first rust removal duration are preset values.

[0011] Preferably, the amount of brake disc corrosion obtained at the current calculation time is based on:

[0012] The amount of brake disc corrosion calculated at the previous calculation time, the amount of new brake disc corrosion generated due to environmental factors from the previous calculation time to the current calculation time, and the amount of brake disc corrosion reduction due to non-environmental factors from the previous calculation time to the current calculation time are all determined.

[0013] Preferably, the reduction in brake disc corrosion caused by non-environmental factors from the previous calculation time to the current calculation time includes: the reduction in first brake disc corrosion caused by hydraulic braking during the period from the previous calculation time to the current calculation time, and the reduction in second brake disc corrosion caused by rust removal during the period from the previous calculation time to the current calculation time.

[0014] Preferably, at the first calculation moment after the vehicle is powered on, the amount of brake disc corrosion calculated at the previous calculation moment is the sum of the amount of brake disc corrosion stored when the vehicle was powered off and the amount of new brake disc corrosion generated due to environmental factors during the vehicle's stationary period.

[0015] Preferably, the amount of brake disc corrosion obtained at the current calculation time is based on:

[0016] The rust level is obtained from the driver's input of the active switching command for brake disc rust level, along with the pre-set rust removal threshold.

[0017] Preferably, the corrosion level carried in the driver's input active switching command for brake disc corrosion level is one of three levels: low, medium, and high.

[0018] When the degree of rust carried in the active switching command for brake disc rust amount input by the driver is low, the product of the preset rust removal threshold and the first preset coefficient is set as the brake disc rust amount obtained at the current moment, and the first preset coefficient is less than 1.

[0019] When the degree of rust carried in the active switching command for brake disc rust amount input by the driver is medium, the preset rust removal threshold is set to the brake disc rust amount obtained at the current moment.

[0020] When the degree of rust carried in the active switching command for brake disc rust amount input by the driver is low, the product of the preset rust removal threshold and the second preset coefficient is set as the brake disc rust amount obtained at the current moment, and the second preset coefficient is greater than 1.

[0021] Preferably, the vehicle condition meeting the preset rust removal conditions means any one of the following conditions:

[0022] Condition 1: The brake pedal travel exceeds the preset travel during the period when the brake pedal is depressed but the hydraulic brakes are not engaged, and the pre-calibrated function for requesting hydraulic pressure is not activated;

[0023] Condition 2: During the period when the brake pedal is depressed and the hydraulic brakes are engaged;

[0024] The first rust removal hydraulic pressure and the first rust removal duration corresponding to condition one are preset values;

[0025] The first rust removal hydraulic pressure corresponding to condition two is the hydraulic pressure determined based on the brake pedal stroke, and the first rust removal duration is the duration of brake pedal depressing.

[0026] Preferably, the method further includes:

[0027] If the cumulative rust removal amount of the vehicle within the preset time is less than the preset wiping amount, the system will actively control the brake pads to perform supplementary rust removal on the brake disc by using the second rust removal hydraulic pressure and the second rust removal duration of the hydraulic cylinder, until the cumulative rust removal amount is greater than or equal to the preset rust removal amount.

[0028] Preferably, the method further includes:

[0029] After the vehicle's windshield wipers have stopped working for a first preset time, after the vehicle has exited wading mode for a second preset time, or after the driver has actively input that the vehicle has been washed for a third preset time, the hydraulic cylinder is actively controlled to perform a rust removal operation with a third preset rust removal hydraulic pressure and a third rust removal duration.

[0030] The beneficial effects of this invention are as follows:

[0031] When the vehicle condition meets the preset rust removal conditions, the system actively performs periodic light wiping motions on the brake discs during driving to remove rust, instead of relying on the driver to press the brake pedal to passively remove rust from the brake discs during the energy recovery process, as is the case with existing technologies. Rust removal can be performed at any time during vehicle operation, thus cleaning up the rust on the brake discs before the driver actually needs to brake. Furthermore, because the existing design initiates rust removal as soon as the driver presses the brake pedal, regardless of the required deceleration, a portion of the vehicle's kinetic energy is always allocated to the mechanical hydraulic system for brake disc rust removal, thus affecting energy recovery performance. In this solution, since the timing of the rust removal action is no longer specifically limited to when the driver presses the brake pedal, when the required deceleration is low, the vehicle's deceleration can be achieved entirely by the motor's reverse drag due to the relatively strong recovery capability (at which point the brake pads and brake disc do not contact or rub). In other words, the vehicle's kinetic energy can be fully utilized for energy recovery, thus not affecting the vehicle's energy recovery performance at low deceleration requirements. Moreover, since the rust removal action is a light wiping action of the brake pads against the brake disc formed by the rust removal hydraulic pressure, it will not affect the vehicle's braking performance. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the brake disc rust removal process based on the brake disc corrosion model in this embodiment;

[0033] Figure 2 This is a schematic diagram of the brake disc rust removal process based on the brake disc rust removal model in this embodiment;

[0034] Figure 3 This is a graph showing the change in rust amount over time during brake disc rust removal in this embodiment. Detailed Implementation

[0035] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0036] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0037] To better illustrate the purpose and advantages of the present invention, the present invention will be further described below with reference to the accompanying drawings, without limiting the present invention.

[0038] This embodiment provides a method for removing rust from a brake disc, the method comprising:

[0039] During vehicle operation, when the vehicle condition is determined to meet the preset rust removal conditions, the hydraulic cylinder is actively controlled to cyclically drive the brake pads to wipe and remove rust from the brake disc with the first rust removal hydraulic pressure and the first rust removal duration, until the vehicle condition changes to no longer meet the preset rust removal conditions.

[0040] When the vehicle condition meets the preset rust removal conditions, the system actively performs periodic light wiping motions on the brake discs during driving to remove rust, instead of relying on the driver to press the brake pedal to passively remove rust from the brake discs during the energy recovery process, as is the case with existing technologies. Rust removal can be performed at any time during vehicle operation, thus cleaning up the rust on the brake discs before the driver actually needs to brake. Furthermore, because the existing design initiates rust removal as soon as the driver presses the brake pedal, regardless of the required deceleration, a portion of the vehicle's kinetic energy is always allocated to the mechanical hydraulic system for brake disc rust removal, thus affecting energy recovery performance. In this solution, since the timing of the rust removal action is no longer specifically limited to when the driver presses the brake pedal, when the required deceleration is low, the vehicle's deceleration can be achieved entirely by the motor's reverse drag due to the relatively strong recovery capability (at which point the brake pads and brake disc do not contact or rub). In other words, the vehicle's kinetic energy can be fully utilized for energy recovery, thus not affecting the vehicle's energy recovery performance at low deceleration requirements. Moreover, since the rust removal action is a light wiping action of the brake pads against the brake disc formed by the rust removal hydraulic pressure, it will not affect the vehicle's braking performance.

[0041] In this embodiment, two methods are provided to set the vehicle state to meet the preset rust removal conditions. In the first method, the vehicle state meeting the preset rust removal conditions means that: the amount of brake disc corrosion obtained at the current calculation time reaches the preset brake disc corrosion threshold, the pre-calibrated functions related to vehicle stability are not activated, and the vehicle speed is within the preset speed range. The first rust removal hydraulic pressure and the first rust removal duration are preset values.

[0042] In the first method, once the amount of rust D on the vehicle's brake disc is determined in real time... act2 Has the preset brake disc corrosion threshold D been reached? thThis triggers the brake disc rust removal and wiping action. However, this action requires certain preconditions: the wiping action cannot be performed if vehicle stability-related functions are activated, or if the vehicle speed is below a set value.

[0043] Combination Figure 1 In this first method, the amount of brake disc corrosion obtained at the current calculation moment is determined using the brake disc corrosion model in the controller. Specifically, the brake disc corrosion model is based on:

[0044] The amount of brake disc corrosion calculated at the previous calculation time, the amount of new brake disc corrosion generated due to environmental factors from the previous calculation time to the current calculation time, and the amount of brake disc corrosion reduction due to non-environmental factors obtained at the calculation time before the determination of the amount of brake disc corrosion from the previous calculation time to the current calculation time.

[0045] After the vehicle is powered on, the brake disc corrosion model in the controller will read the amount of brake disc corrosion D stored when the vehicle was last powered off via diagnostic commands. NvM Simultaneously calculate the amount of rust formation D during the vehicle's stationary period (the period between the last power-off and the current power-on). ss The sum of the two values ​​is defined as the amount of brake disc corrosion D when the vehicle is powered on. act1 ,Right now

[0046] D act1 =D NvM +D ss

[0047] Among them, the amount of rust formed during the vehicle's stationary period, D ss It is strongly correlated with ambient humidity (W) and ambient temperature (T), and the related rust formation amount (D) is... gen (W, T) needs to be obtained through experimental testing. When calculating the degree of brake disc corrosion, the controller needs to periodically record the ambient temperature and humidity. Alternatively, it can read local ambient temperature and humidity values ​​published by the meteorological bureau via the network. Based on the obtained ambient temperature and humidity data, the amount of corrosion generated per unit time, D, can be calculated by referring to a table. gen (W, T), summed over time, gives an estimate of the amount of rust formed on the vehicle during its stationary period, i.e.:

[0048] D ss =∫D gen (W, T)·dt

[0049] Based on the aforementioned process, the amount of new brake disc corrosion generated after the vehicle is powered off can be determined.

[0050] Furthermore, at the first calculation moment after the vehicle is powered on, the previously determined brake disc corrosion amount D... act1The amount of brake disc corrosion D determined at the previous calculation time. actLast That is, at the first calculation moment after the vehicle is powered on, the amount of brake disc corrosion D determined at the previous calculation moment. act1 The amount of brake disc corrosion D stored when the vehicle was last powered off. NvM The amount of new brake disc corrosion generated while the vehicle is stationary (D) ss sum.

[0051] Furthermore, under normal driving conditions, the brake disc corrosion model needs to monitor the reduction in brake disc corrosion caused by non-environmental factors in real time. Specifically, it is necessary to monitor the hydraulic pressure of the hydraulic cylinder in real time to calculate the reduction in the first brake disc corrosion caused by hydraulic braking. This hydraulic braking is caused by the driver pressing the brake pedal heavily. When the driver presses the brake pedal heavily, due to the limited regenerative braking capacity of the motor, it cannot fully provide the deceleration required by the driver. Therefore, the friction between the brake pads and the brake disc is used to compensate for the remaining deceleration that the motor cannot provide, resulting in a reduction in brake disc corrosion. Therefore, in this scheme, the reduction in the first brake disc corrosion caused by hydraulic braking does not exist at all calculation moments; it only occurs when the driver requires a large deceleration that the motor cannot provide. Specifically, when hydraulic braking intervenes, the corresponding reduction in the first brake disc corrosion, D... brk According to the braking hydraulic pressure p brk The result is obtained by integrating the hydraulic braking duration t.

[0052] D brk =∫f wip ·p brk ·dt

[0053] Where f wip The wiping coefficient is a value that is pre-designed.

[0054] Furthermore, under normal driving conditions, the brake disc corrosion model needs to monitor the ambient humidity W and ambient temperature T in real time and calculate the amount of corrosion D generated per unit time by referring to a table. gen (W, T), the amount of rust generated on the brake discs under normal driving conditions, D Drv for:

[0055] D Drv =∫D gen (W, T)·dt

[0056] When the vehicle is in normal driving condition, the controller needs to determine the amount of brake disc corrosion D calculated by the brake disc corrosion model at the current calculation time. act Has the preset brake disc corrosion threshold D been reached? th This triggers the brake disc rust removal and wiping action. For example... Figure 2 and3 When the amount of brake disc corrosion D at a certain calculation moment act The preset brake disc corrosion threshold D has been reached. th When the time comes, the rust removal will proceed according to the preset rust removal cycle T. cyc Rust removal is performed. During the rust removal process, the first rust removal step lasts for a duration of T. act1 The first rust removal hydraulic pressure is p act1 The corresponding reduction in corrosion of the second brake disc, D wip (p act1 T act1 ) calculated as

[0057]

[0058] Where f wip It is the rust removal wiping coefficient, which is predetermined and used to achieve light wiping rust removal of the brake disc.

[0059] Combined with appendix Figure 3 As can be seen, the above-mentioned rust removal cycle T cyc1 Including a first rust removal duration T act1 And a rust removal interval, during which the first rust removal lasts for a duration T act1 In the process, the active control hydraulic cylinder operates at the aforementioned first rust-removing hydraulic pressure p. act The controller moves the brake pads to wipe and remove rust from the brake disc; during the rust removal interval, the controller does not control the hydraulic cylinder to move the brake pads to wipe and remove rust from the brake disc. In other words, the controller will periodically and actively control the hydraulic cylinder to control the brake pads to wipe and remove rust from the brake disc by adjusting the rust removal hydraulic pressure and the duration of rust removal.

[0060] like Figure 1 Therefore, based on the above description, the amount of brake disc corrosion D at the current calculation time is... act2 for

[0061] D act2 =D actLast +D Drv -D brk -D wip

[0062] Where D actLast D represents the amount of brake disc corrosion calculated at the previous calculation time. brk The reduction in corrosion of the aforementioned first brake disc; DD rv For the aforementioned amount of brake disc corrosion, D wip This is to reduce the amount of corrosion on the aforementioned second brake disc.

[0063] Subsequently, when the vehicle is powered off, the aforementioned brake disc corrosion model needs to invoke diagnostic commands to determine the current amount of corrosion D on the brake disc. act2The information is recorded in the NvM memory for future use upon the next power-on.

[0064] In this embodiment, the brake disc corrosion model also introduces a driver-input calibration interface for brake disc corrosion amount. When the driver actively requests the rust removal function through the human-machine interface (i.e., the driver inputs a driver-input command to actively switch the brake disc corrosion amount), the brake disc corrosion amount at the current calculation time can be reset. In the next calculation time, the reset brake disc corrosion amount at the current calculation time will be used to trigger the brake disc rust removal action. Based on the actual observed corrosion amount, the driver can select low, medium, or high corrosion levels when actively switching the brake disc corrosion amount.

[0065] Low degree of rust does not require wiping, reset D act2 = First preset coefficient · D th ;

[0066] Medium level of rust requires wiping and resetting D. act2 =D th ;

[0067] High degree of corrosion requires wiping and resetting D. act2 =Second preset coefficient·D th .

[0068] Among them, the first preset coefficient is less than 1, and the second preset coefficient is greater than 1.

[0069] Furthermore, based on the aforementioned vehicle condition meeting the preset rust removal requirements, the first rust removal hydraulic pressure and the first rust removal duration were obtained through prior testing. During the preliminary test, the hydraulic pressure and rust removal duration were determined by lightly wiping the brake disc with the brake pads without causing the driver to feel any abnormal deceleration. If the hydraulic pressure is too low, the rust removal effect will be poor; if the rust removal pressure is too high, the driver will feel any abnormal deceleration. Therefore, it is necessary to make extremely reasonable adjustments to the first preset hydraulic pressure and the first rust removal duration. Meanwhile, if the vehicle condition does not meet the preset rust removal conditions, continuous rust removal of the brake disc may also cause the vehicle speed to decrease. Therefore, this application has made a special design for the rust removal process, namely, "controlling the hydraulic cylinder to cyclically drive the brake pads to wipe and remove rust from the brake disc with a first preset rust removal hydraulic pressure and a first preset rust removal duration". Here, "cyclically" means that after the hydraulic cylinder outputs the rust removal hydraulic pressure for the rust removal duration, it will pause for a very short period of time to stop rust removal from the brake disc, and then repeat the process. During this very short pause, the vehicle speed is slowed down to decrease continuously at a very small rate.

[0070] In this embodiment, for vehicle models where a brake disc corrosion model cannot be established, a method is also provided to determine whether the vehicle condition meets the rust removal conditions, such as... Figure 2 Since the ambient humidity and temperature values ​​cannot be obtained, another way to design the vehicle condition to meet the rust removal conditions is to ensure that the vehicle condition meets the rust removal conditions, which means that the vehicle condition meets the rust removal conditions according to any one of the following conditions:

[0071] Condition 1: The brake pedal travel exceeds the preset travel during the period when the brake pedal is depressed but the hydraulic brakes are not engaged, and the pre-calibrated function for requesting hydraulic pressure is not activated;

[0072] Condition 2: During the period when the brake pedal is depressed and the hydraulic brakes are engaged;

[0073] The first rust removal hydraulic pressure and the first rust removal duration corresponding to condition one are preset values. However, the first rust removal hydraulic pressure is the second preset rust removal hydraulic pressure and the first rust removal duration is the second preset rust removal duration. That is, the specific values ​​of the second preset rust removal hydraulic pressure and the second preset rust removal duration need to be determined according to this vehicle model.

[0074] The first rust removal hydraulic pressure corresponding to condition two is the hydraulic pressure determined based on the brake pedal stroke, and the first rust removal duration is the duration of brake pedal depressing.

[0075] Specifically, for vehicle models where a brake disc corrosion model cannot be established, during the period when the brake pedal is depressed but the hydraulic brakes are not engaged, when each detection shows that the brake pedal travel L > the preset travel L... th At that time, the brake disc wiping action is performed, and the second preset rust-removing hydraulic pressure p, which is pre-calibrated in the hydraulic cylinder, is controlled. act2 The wiping action is performed when the brake pedal travel L ≤ the preset travel L. th Stop when the time is right. Simultaneously calculate the active rust removal amount W. Wip :

[0076] W Wip =∫f wip ·p act2 ·dt

[0077] When a pressure request for other functions related to vehicle braking is activated, the pre-calibrated second preset rust-removing hydraulic pressure p act2 It will no longer be executed.

[0078] When the hydraulic brake is engaged, it operates according to the actual hydraulic pressure p. act3 (That is, the first rust removal hydraulic pressure at this time is the actual hydraulic pressure p determined based on the brake pedal travel.) act3 ), calculate the wiping amount W under hydraulic braking. Brk The calculation formula is as follows:

[0079] WBrk =∫f wip ·p act3 ·dt,

[0080] Where f wip It is the wiping coefficient.

[0081] In this embodiment, for the vehicle model for which the brake disc corrosion model is established, an evaluation of the cumulative rust removal amount within a preset time period is provided to determine whether supplementary rust removal is needed. That is, if the cumulative rust removal amount of the vehicle within the preset time period is lower than the preset wiping amount, the system actively controls the brake pads to perform supplementary rust removal on the brake disc by cyclically driving the second rust removal hydraulic pressure and the second rust removal duration of the hydraulic cylinder until the cumulative rust removal amount is greater than or equal to the preset rust removal amount.

[0082] Specifically, the system detected that during the preset duration T Set (e.g., within one week) the cumulative rust removal amount W Sum for:

[0083] W Sum =W Wip +W Brk

[0084] If the cumulative rust removal amount W Sum No more than the preset wiping amount W Th If necessary, a supplementary wiping action will be performed on the brake disc to compensate for insufficient wiping. The wiping cycle for supplementary rust removal is T. cyc2 The wiping cycle is T. cyc2 Including a second rust removal duration T act2 And a rust removal gap, the second rust removal hydraulic pressure p is executed wip All are pre-designed; the wiping amount W supplemented by the brake disc wiping pressure. WipRep The calculation formula is as follows:

[0085] W WipRep =∫f wip ·p wip ·dt

[0086] When the brake disc wiping pressure replenishes the wiping amount W WipRep Reaching the default value, i.e., W WipRep ≥W Th -W Sum If the current wiping volume compensation action is interrupted, the system will proceed to the next T cycle. Set Duration detection.

[0087] Considering the humid environment encountered by the vehicle during operation, such as after rain, wading, or car washing, where a water film may remain on the brake discs leading to rust, the following control strategy is designed to prevent rust: Rust removal is performed once the windshield wipers have stopped for a first preset time, once the vehicle has exited wading mode for a second preset time, or once the driver has actively input that the vehicle has been washed for a third preset time, according to the pre-defined rust removal pressure and duration. Specifically:

[0088] T for a period of time after the wipers stop working WipExt Within the first preset duration, the brake disc wiping action is performed, with a wiping cycle T. CycRain Wiping execution time T ActRain Execution pressure P rain ;

[0089] After the vehicle has exited wading mode for a period of time T WadExt Within the second preset time period, the brake disc wiping action is performed, with a wiping cycle T. CycWade Wiping execution time T ActWade Execution pressure P Wade ;

[0090] A period of time T after the driver actively inputs the car wash status WashExt Within the third preset time period, the brake disc wiping action is performed, with a wiping cycle T. cycWash Wiping execution time T ActWash Execution pressure P Wash .

[0091] In this embodiment, the above-described solution no longer specifically limits the timing of the rust removal action to the brake disc rust removal when the driver applies the brakes. When the deceleration required by the driver is relatively small, the vehicle deceleration can be achieved entirely by the motor's reverse drag due to the relatively strong recovery capability (at this time, the brake pads and brake discs do not come into contact or rub against each other). That is, the vehicle's kinetic energy can be fully used for energy recovery, so the energy recovery performance of the vehicle can be completely unaffected under low deceleration requirements. Furthermore, since the rust removal action is a light wiping action of the brake pads against the brake disc formed by the rust removal hydraulic pressure, it will not affect the vehicle's braking performance.

[0092] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for removing rust from brake discs, characterized in that, include: During vehicle operation, when the vehicle condition is determined to meet the preset rust removal conditions, the hydraulic cylinder is actively controlled to cyclically drive the brake pads to wipe and remove rust from the brake disc with the first rust removal hydraulic pressure and the first rust removal duration, until the vehicle condition changes to no longer meet the preset rust removal conditions. The vehicle status meets the preset rust removal conditions as follows: the amount of brake disc corrosion obtained at the current calculation time reaches the preset brake disc corrosion threshold, the pre-calibrated functions related to vehicle stability are not activated, and the vehicle speed is within the preset speed range. The first rust removal hydraulic pressure and the first rust removal duration are preset values; The amount of brake disc corrosion calculated at the current moment is based on: The amount of brake disc corrosion calculated at the previous calculation time, the amount of new brake disc corrosion generated due to environmental factors from the previous calculation time to the current calculation time, and the amount of brake disc corrosion reduced due to non-environmental factors from the previous calculation time to the current calculation time are determined. The reduction in brake disc corrosion caused by non-environmental factors from the previous calculation time to the current calculation time includes: the reduction in first brake disc corrosion caused by hydraulic braking during the period from the previous calculation time to the current calculation time, and the reduction in second brake disc corrosion caused by rust removal during the period from the previous calculation time to the current calculation time.

2. The brake disc rust removal method according to claim 1, characterized in that, At the first calculation moment after the vehicle is powered on, the amount of brake disc corrosion calculated at the previous calculation moment is the sum of the amount of brake disc corrosion stored when the vehicle was powered off and the amount of new brake disc corrosion generated due to environmental factors during the vehicle's stationary period.

3. The brake disc rust removal method according to claim 1, characterized in that, The amount of brake disc corrosion calculated at the current moment is based on: The rust level is obtained from the driver's input of the active switching command for brake disc rust level, along with the pre-set rust removal threshold.

4. The brake disc rust removal method according to claim 3, characterized in that, The driver inputs an active switching command for brake disc corrosion level, specifying one of three corrosion levels: low, medium, or high. When the degree of rust carried in the active switching command for brake disc rust amount input by the driver is low, the product of the preset rust removal threshold and the first preset coefficient is set as the brake disc rust amount obtained at the current moment, and the first preset coefficient is less than 1. When the degree of rust carried in the active switching command for brake disc rust amount input by the driver is medium, the preset rust removal threshold is set to the brake disc rust amount obtained at the current moment. When the degree of rust carried in the active switching command for brake disc rust amount input by the driver is high, the product of the preset rust removal threshold and the second preset coefficient is set as the brake disc rust amount obtained at the current moment, and the second preset coefficient is greater than 1.

5. The brake disc rust removal method according to claim 1, characterized in that, The vehicle condition meets the preset rust removal conditions if any one of the following conditions is met: Condition 1: The brake pedal travel exceeds the preset travel during the period when the brake pedal is depressed but the hydraulic brakes are not engaged, and the pre-calibrated function for requesting hydraulic pressure is not activated; Condition 2: During the period when the brake pedal is depressed and the hydraulic brakes are engaged; The first rust removal hydraulic pressure and the first rust removal duration corresponding to condition one are preset values; The first rust removal hydraulic pressure corresponding to condition two is the hydraulic pressure determined based on the brake pedal stroke, and the first rust removal duration is the duration of brake pedal depressing.

6. The brake disc rust removal method according to claim 5, characterized in that, The method further includes: If the cumulative rust removal amount of the vehicle within the preset time is less than the preset wiping amount, the system will actively control the brake pads to perform supplementary rust removal on the brake disc by using the second rust removal hydraulic pressure and the second rust removal duration of the hydraulic cylinder, until the cumulative rust removal amount is greater than or equal to the preset rust removal amount.

7. The brake disc rust removal method according to claim 1, characterized in that, The method further includes: After the vehicle's windshield wipers have stopped working for a first preset time, after the vehicle has exited wading mode for a second preset time, or after the driver has actively input that the vehicle has been washed for a third preset time, the hydraulic cylinder is actively controlled to perform a rust removal operation with a third preset rust removal hydraulic pressure and a third rust removal duration.

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