Anti-lock braking control method, system and electromechanical braking device

Abstract

The present application discloses an anti-lock braking control method, system and electromechanical braking device, wherein the anti-lock braking control method only needs to measure the wheel angular acceleration, and through continuous control cycles, the vehicle is caused to perform a reciprocating operation of deceleration and acceleration during braking, thereby preventing the wheel from locking and shortening the braking distance; the electromechanical braking device disclosed in the present invention utilizes the principle of leverage to convert the braking torque applied to the brake into a force acting on the brake pad, and braking is achieved by the brake wedge. The force transmission is completed by a mechanical structure, and a complex hydraulic power device is not required. Compared with conventional hydraulic-electric braking devices, the structure is simpler, there is no pedal vibration when used for anti-lock braking, the braking torque control is more accurate, and the braking efficiency and stability are improved.

Description

Technical Field

[0001] The present invention relates to vehicle braking technology, and in particular to an anti-lock braking control method, system and electromechanical braking device. Background Art

[0002] Anti-lock braking systems (ABS) are one of the most commonly used braking technologies in automobiles. They prevent wheels from locking during braking, providing active safety protection. Their ideal goal is to maximize tire-road adhesion, or adhesion coefficient, to achieve handling stability, steering performance, and short braking distances. In addition to wheel speed, common braking control methods require measuring parameters such as vehicle speed or acceleration, maximum tire slip, vehicle mass, braking torque, and wheel forces. However, with the exception of wheel speed, which can be measured directly on the vehicle, these other parameters are difficult to accurately measure.

[0003] In addition, most of the current ABS are hydraulic brakes. The braking torque mainly comes from the pressure of the brake fluid. The control of the braking torque depends on the valve and pump. The transmission of torque is based on brake fluid and cylinders, which makes the brake structure complex and the dynamic performance and accuracy of torque control are also limited. Summary of the Invention

[0004] Based on this, the present invention proposes an anti-lock braking control method, system and electromechanical braking device that only need to detect tire angular velocity to maximize real-time tire-road adhesion and adhesion coefficient, while preventing wheel locking and shortening braking distance to overcome the shortcomings of existing braking technology.

[0005] In a first aspect, the present invention provides an anti-lock braking control method, which is performed through continuous control cycles, each control cycle including a deceleration phase and an acceleration phase, and the control method includes:

[0006] The vehicle triggers anti-lock braking and enters the deceleration stage, and the wheels decelerate under the action of the first braking torque;

[0007] When the wheel angular acceleration reaches the local maximum value of the angular acceleration in the deceleration phase of the current control cycle, the adhesion force / adhesion coefficient reaches the maximum value, the wheel stops decelerating, and enters the acceleration phase;

[0008] The wheel accelerates under the action of the second braking torque. When the wheel angular acceleration reaches the wheel angular acceleration reference value of the current control cycle, the adhesion / adhesion coefficient reaches the defined value, the wheel stops accelerating, and enters the next control cycle.

[0009] Furthermore, the calculation of the first braking torque includes:

[0010] The first braking torque of the current control cycle is calculated according to the first braking torque of the previous control cycle and the wheel angular acceleration reference value.

[0011] Furthermore, the calculation of the second braking torque includes:

[0012] The second braking torque of the current control cycle is calculated according to the second braking torque of the previous control cycle and the local maximum value of the angular acceleration in the deceleration phase of the current control cycle.

[0013] Furthermore, the calculation of the first braking torque of the current control cycle includes:

[0014] According to the first braking torque of the previous control cycle and the wheel angular acceleration reference value, the relationship between the first braking torques of two adjacent control cycles is established as follows:

[0015] T bwd,k =T bwd,k+1 +C d (a wdef,k+1 -a wd,obj )

[0016] Among them, T bwd,k represents the first braking torque of the kth control cycle, T bwd,k-1 represents the first braking torque of the k-1th control cycle, C d represents the differential constant, a wdef,k-1 represents the wheel angular acceleration reference value of the k-1th control cycle, a wd,obj Indicates the target value of the wheel angular acceleration during the wheel deceleration phase.

[0017] Furthermore, the calculation of the second braking torque in the current control cycle includes:

[0018] According to the second braking torque of the previous control cycle and the local maximum value of angular acceleration in the deceleration phase of the current control cycle, the relationship between the second braking torques of two adjacent control cycles is established as follows:

[0019] T bwa,k =T bwa,k-1 +C d (a wdx,k -a wa,obj )

[0020] Among them, T bwa,k represents the second braking torque of the kth control cycle, T bwa,k-1 represents the second braking torque of the k-1th control cycle, C d represents the differential constant, a wdx,k represents the local maximum value of angular acceleration during the wheel deceleration phase of the kth control cycle, a wa,obj Indicates the target value of the wheel angular acceleration during the wheel acceleration phase.

[0021] Furthermore, the calculation of the wheel angular acceleration reference value is as follows:

[0022] a wdef,k =k a a wax,k

[0023] Among them, a wdef,k represents the wheel angular acceleration reference value of the kth control cycle, k a Indicates the attenuation coefficient of the wheel angular acceleration during the wheel acceleration phase, a wax,k It represents the local maximum value of angular acceleration during the wheel acceleration phase of the kth control cycle.

[0024] Furthermore, the calculation of adhesion and adhesion coefficient includes:

[0025] The relationship between wheel angular acceleration and adhesion is established as follows

[0026] F afw =C afw (a w +C bw T bw )

[0027] Among them, C afw =J w / r w , C bw =1 / J w , F afw Indicates adhesion, a w represents the wheel angular acceleration, J w represents the moment of inertia of the wheel, r w Indicates the wheel radius, T bw Indicates braking torque;

[0028] The relationship between wheel angular acceleration and adhesion coefficient is established as follows

[0029] μ af =C uaf (a w +C bw T bw )

[0030] Among them, C uaf =J w / (r w F w ), represents the adhesion coefficient, F w Indicates the vertical force acting on the wheel.

[0031] Furthermore, the wheel angular acceleration is calculated based on the continuously measured wheel speed.

[0032] In a second aspect, the present invention provides an anti-lock braking control system for implementing the braking control method of the first aspect, comprising:

[0033] an electronic control unit configured to store a computer program, which, when executed, implements the anti-lock braking control method of the first aspect and outputs a braking control signal corresponding to the first braking torque or the second braking torque;

[0034] The brake control unit is configured to receive a brake control signal from the electronic control unit and to control the brake device to generate a braking torque corresponding to the brake control signal.

[0035] Furthermore, the above system also includes a wheel speed sensor configured to be connected to the electronic control unit, for detecting the wheel speed and sending it to the electronic control unit to calculate the wheel angular acceleration.

[0036] In a third aspect, the present invention provides an electromechanical braking device for generating the first braking torque or the second braking torque in the control method of the first aspect to act on a wheel, comprising:

[0037] The brake is fastened to the brake bracket via a first fixing member and is connected to the brake wedge via a lever structure. The brake drives the lever structure to rotate relative to the brake bracket under the action of a braking force.

[0038] One side of the brake wedge contacts the first brake pad, and the other side is slidably connected to the brake caliper. The brake caliper is fastened to the brake bracket through a second fixing member. The second brake pad is arranged between the brake caliper and the brake wedge, and the brake disc is arranged between the first brake pad and the second brake pad.

[0039] The braking force acting on the brake is transmitted to the brake wedge through the lever structure. Under the action of the force, the brake wedge squeezes the first brake pad, causing the first brake pad and the second brake pad to move toward each other and contact the brake disc or move in the opposite direction away from the brake disc.

[0040] Further, the lever structure includes a first end, a second end, and a third end;

[0041] The first end and the second end are pivotally connected to the brake using a first connecting member and a second connecting member respectively, and the third end is pivotally connected to the brake wedge using a third connecting member. The first end and the third end pivot on the second connecting member with the movement of the brake, and the pivoting of the third end drives the brake wedge to slide relative to the brake caliper.

[0042] Furthermore, in the above lever structure, the distance between the first end and the second end is greater than the distance between the second end and the third end.

[0043] Furthermore, the brake includes a frame, a stator and a mover;

[0044] The stator is fixed on the frame and is arranged around the outside of the mover;

[0045] The mover is pivotally connected to the first end of the lever structure through the first connecting member. When a braking force is applied, the mover moves in a vertical direction, driving the first end of the lever structure to pivot on the second connecting member.

[0046] In a fourth aspect, the present invention provides a vehicle on which is installed the anti-lock braking control system of the second aspect for implementing the anti-lock braking control method of the first aspect, and the vehicle is provided with at least one electromechanical braking device of the third aspect.

[0047] Furthermore, the vehicle has a plurality of wheels, and each wheel is provided with the electromechanical brake device according to the third aspect.

[0048] The present invention has the following beneficial effects:

[0049] The present invention discloses an anti-lock braking control method, system and electromechanical braking device. The anti-lock braking control method observes the changes in adhesion and adhesion coefficient by detecting wheel angular acceleration, and maximizes the real-time adhesion and adhesion coefficient of the vehicle during braking through a cycle of deceleration and acceleration, thereby preventing wheel lock and shortening the braking distance. Since only the wheel angular acceleration needs to be measured, the method is applicable to various road surfaces, vehicle speeds and vehicle loads. The electromechanical braking device disclosed in the present invention utilizes the principle of leverage to convert the braking torque applied to the brake into a force acting on the brake pad, and braking is achieved by a brake wedge. The force transmission is completed by a mechanical structure, and a complex hydraulic power device is not required. Compared with conventional hydraulic-electric braking devices, the structure is simpler, there is no pedal vibration when used for anti-lock braking, the braking torque control is more accurate, and the braking efficiency and stability are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0051] Figure 1 An implementation process of the anti-lock braking control method provided in an embodiment of the present invention;

[0052] Figure 2 Another flowchart of the anti-lock braking control method provided by an embodiment of the present invention is shown;

[0053] Figure 3 Another implementation process of the anti-lock braking control method provided by an embodiment of the present invention;

[0054] Figure 4The parameter changes of simulating anti-lock braking on a dry asphalt road provided by the embodiment of the present invention;

[0055] Figure 5 The parameter changes for simulating anti-lock braking on a wet asphalt road provided by an embodiment of the present invention;

[0056] Figure 6 The embodiment of the present invention provides parameter changes for simulating anti-lock braking on a snowy road surface;

[0057] Figure 7 The embodiment of the present invention provides parameter changes for simulating anti-lock braking on icy roads;

[0058] Figure 8 A schematic diagram of the structure of an anti-lock braking control system provided by an embodiment of the present invention;

[0059] Figure 9 A schematic diagram of the overall structure of an electromechanical braking device provided in an embodiment of the present invention;

[0060] Figure 10 A schematic diagram of the partial structure of an electromechanical braking device provided in an embodiment of the present invention;

[0061] Figure 11 A top view of an electromechanical braking device provided in an embodiment of the present invention;

[0062] Figure 12 for Figure 11 Cross-sectional view in the AA direction;

[0063] Figure 13 An exploded view of the components of the electromechanical braking device provided by an embodiment of the present invention;

[0064] Figure 14 Schematic diagram of the application of the electromechanical braking device provided in an embodiment of the present invention;

[0065] Figure 15 A schematic diagram of the vehicle structure provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0066] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0067] Example 1

[0068] See Figure 1This embodiment provides an anti-lock braking control method, which controls the braking torque by observing the wheel angular acceleration, so that the wheel operates cyclically, and each control cycle includes a deceleration phase and an acceleration phase of the wheel.

[0069] When the vehicle triggers anti-lock braking, the wheels enter the deceleration phase of the first control cycle and decelerate under the action of the first braking torque.

[0070] At the beginning of deceleration, the wheel angular acceleration reaches the minimum value (maximum absolute value) of the current deceleration stage. After that, the wheel slides and decelerates, and the angular acceleration continues to increase (absolute value decreases). Therefore, the adhesion F afw and adhesion coefficient μ af Increase, when the wheel angular acceleration reaches the maximum value of the current deceleration stage, the adhesion / adhesion coefficient (F afw / μ af )This parameter also reaches its maximum value. According to the principles of conventional mechanics, the wheel stops accelerating and enters the acceleration phase of the control cycle.

[0071] The wheel accelerates under the action of the second braking torque. At the beginning of acceleration, the wheel angular acceleration reaches the maximum value (absolute value maximum) of the current acceleration stage. After that, the wheel slides and accelerates, and the angular acceleration continues to decrease (absolute value decreases). However, since the wheel is accelerating, the adhesion F afw and adhesion coefficient μ af When the wheel angular acceleration decreases to the set reference value, the adhesion / adhesion coefficient (F afw / μ af ) is recorded as the defined value, and the control wheel stops accelerating at this time and enters the next control cycle.

[0072] The embodiment of the present invention controls the change of the braking torque by observing the change of angular acceleration. The deceleration stage and acceleration stage are repeated in each control cycle. The braking torque remains constant in each deceleration stage or acceleration stage. In the process of continuous control of the braking torque, F afw / μ af Always maintain a stable value range, that is, between the defined value and the maximum value. In other words, F afw / μ af The real-time value of is always close to the maximum value. Through such a control cycle, the real-time values ​​of adhesion and adhesion coefficient are maximized, and only the wheel angular acceleration needs to be detected, which is applicable to various road conditions, vehicle speeds and vehicle loads.

[0073] In a further embodiment, the relationship between adhesion force and adhesion coefficient and angular acceleration is established as follows:

[0074] F afw =C afw (a w+C bw T bw )

[0075] μ af =C uaf (a w +C bw T bw )

[0076] Among them, C afw =J w / r w , C bw =1 / J w , C uaf =J w / (r w F w ), F afw Indicates adhesion, a w represents the wheel angular acceleration, J w represents the moment of inertia of the wheel, r w Indicates the wheel radius, T bw represents the braking torque, represents the adhesion coefficient, F w Indicates the vertical force acting on the wheel.

[0077] The above C afw 、C bw 、C uaf can all be regarded as constants. Therefore, it can be seen from the above formula that when the braking torque remains constant, the adhesion force and adhesion coefficient depend on the wheel angular acceleration. That is, when the braking torque remains unchanged for a period of time, the change in wheel angular acceleration can reflect the change in adhesion force and adhesion coefficient. For a constant braking torque, when the wheel angular acceleration reaches a local maximum, the adhesion force or adhesion coefficient also reaches its maximum value.

[0078] Example 2

[0079] In order to make readers more clear about the implementation process of the anti-lock braking control method provided by the present invention, the following Figure 2 The braking torque, angular acceleration, wheel speed and adhesion / adhesion coefficient F during this method are afw / μ af to clarify the changes.

[0080] See Figure 2 , which shows the comparison and change of various parameters between two consecutive control cycles. The essence of the control process is to control the braking torque to make the wheel decelerate and accelerate cyclically. Among them, 200a is a schematic diagram of the change of braking torque over time, 200b is a schematic diagram of the change of wheel angular acceleration over time, 200c is a schematic diagram of the change of wheel speed over time, and 200d is the adhesion / adhesion coefficient (F afw / μ af ) changes over time.

[0081] At time t0, the control braking torque is T bwd,1 And it remains constant during the deceleration phase of the first control cycle, the wheel angular acceleration a w Less than 0, reaches the minimum value a at time t0 wdn,0 , wheel speed is ω w0 , the wheel enters the deceleration phase of the first control cycle, a w increases (the absolute value decreases), so F afw / μ af Increase. When a w Increase to the maximum value of the deceleration stage, that is, the local maximum a wdx,1 When F afw / μ af Also reaches the maximum value F afw,max / μ af,max , at this time the wheel speed is ω w1 , the wheels stop decelerating and enter the acceleration phase of the first control cycle.

[0082] At time t1, the control braking torque is T bwa,1 And keep it constant during the acceleration phase of the first control cycle, so that the angular acceleration a w is greater than 0 and starts from the maximum value a in the deceleration phase wdx,1 becomes the maximum value a in the acceleration phase wax,1 , the wheel enters the acceleration phase of the first control cycle, a w Decreases (the absolute value is decreasing), so F afw / μ af Decrease. When a w Reduce to the angular acceleration reference value a of the first control cycle wdef,1 When F afw / μ af Also reaches the defined value F afw,def / μ af,def , at this time the wheel speed is ω w2 , controlling the wheels to stop accelerating and enter the deceleration phase of the next control cycle.

[0083] In the deceleration phase of the second control cycle, the braking torque is T bwd,2 , angular acceleration a w Reaching the local maximum a of the deceleration stage wdx,2 When the wheel stops decelerating and enters the acceleration phase, the vehicle braking is completed through continuous control cycles, which can make the adhesion / adhesion coefficient F afw / μ af Always close to the maximum value F afw,max / μ af,max .

[0084] In a further embodiment, the first braking torque of the current control cycle is calculated based on the first braking torque of the previous control cycle and the wheel angular acceleration reference value. Specifically, the relationship between the first braking torques of two adjacent control cycles is established as follows:

[0085] T bwd,k =T bwd,k-1 +C d (a wdef,k-1 -a wd,obj )

[0086] Among them, T bwd,k represents the first braking torque of the kth control cycle, T bwd,k-1 represents the first braking torque of the k-1th control cycle, C d represents the differential constant, a wdef,k-1 represents the wheel angular acceleration reference value of the k-1th control cycle, a wd,obj Indicates the target value of the wheel angular acceleration during the wheel deceleration phase, a wd,obj <0.

[0087] In a further embodiment, the second braking torque of the current control cycle is calculated based on the second braking torque of the previous control cycle and the local maximum value of the angular acceleration in the deceleration phase of the current control cycle. Specifically, the relationship between the second braking torques of two adjacent control cycles is established as follows:

[0088] T bwa,k =T bwa,k-1 +C d (a wdx,k -a wa,obj )

[0089] Among them, T bwa,k represents the second braking torque of the kth control cycle, T bwa,k-1 represents the second braking torque of the k-1th control cycle, C d represents the differential constant, a wdx,k represents the local maximum value of angular acceleration during the wheel deceleration phase of the kth control cycle, a wa,obj Indicates the target value of wheel angular acceleration during the wheel acceleration phase, a wa,obj >0.

[0090] In a further embodiment, the wheel angular acceleration reference value is calculated as follows:

[0091] a wdef,k =k a a wax,k

[0092] Among them, a wdef,krepresents the wheel angular acceleration reference value of the kth control cycle, k a Indicates the attenuation coefficient of the wheel angular acceleration during the wheel acceleration phase (0<k a <1), a wax,k It represents the local maximum value of angular acceleration during the wheel acceleration phase of the kth control cycle.

[0093] Example 3

[0094] Based on the above description of the anti-lock braking control method disclosed in the present invention, it can be used Figure 3 To briefly explain the braking control process, Figure 3 One of the situations of the braking control process is shown.

[0095] 201a indicates that the wheel enters the kth control cycle, and then executes 201b.

[0096] 201b represents the calculation of the braking torque in the deceleration phase of this control cycle, which depends on the braking torque in the deceleration phase of the previous control cycle and the reference value of the wheel angular acceleration, and the target value of the wheel angular acceleration a wd,obj <0, under this constant braking torque, the wheel speed decreases, the angular acceleration is less than 0 and increases, F afw / μ af Increased accordingly.

[0097] Go to 201c and determine whether the angular acceleration reaches the local maximum value a wdx,k If not reached, it means F afw / μ af Has not yet reached its maximum value F afw,max / μ af,max , the wheel continues to decelerate. The angular acceleration reaches a local maximum value a wdx,k When , the braking torque is controlled to change and enter the acceleration phase 201d of this control cycle.

[0098] 201d represents the calculation of the braking torque in the acceleration phase of this control cycle, which depends on the braking torque in the acceleration phase of the previous control cycle and the local maximum value of the angular acceleration in the deceleration phase of this control cycle, and the target value of the wheel angular acceleration a wa,obj >0, under this constant braking torque, the wheel accelerates, the angular acceleration is greater than 0 and decreases, F afw / μ af Then it decreases.

[0099] Entering 201e, the angular acceleration reference value of the current control cycle is calculated, which depends on the local maximum value of the acceleration phase of the current control cycle.

[0100] Enter 201f and determine whether the angular acceleration reaches the reference value a wdef,k If not reached, it means F afw / μ af Has not yet reached the defined value F afw,def / μ af,def , the wheel continues to accelerate. The angular acceleration reaches the reference value a wdef,k When the braking torque is controlled to change, the next control cycle is entered, 201g updates the cycle number, and 201a to 201g are executed cyclically.

[0101] It is easy to understand that Figure 3 It only shows one of the control flow situations and is not a limitation of the embodiments of the present invention. The execution order of the steps can be changed without departing from the technical solution of the present invention. For example, 201d and 201e can be executed at the same time.

[0102] In order to illustrate the applicability and stability of the anti-lock braking control method disclosed in the embodiment of the present invention, the following Figures 4 to 7 To clarify.

[0103] See Figure 4 202 represents a simulated braking operation using the anti-lock braking control method of an embodiment of the present invention, simulating an initial vehicle speed of 120 km / h on a dry asphalt road. 202a represents the simulated vehicle speed (Vehicle) and wheel peripheral speed (Wheel), 202b represents the braking distance, 202c shows the changes in the maximum adhesion coefficient (Maximum) and the real-time adhesion coefficient (Real-time), and 202d represents the braking torque. It can be seen that for braking on a dry asphalt road, the anti-lock braking control method of the present invention can force the real-time adhesion coefficient to always approach the maximum adhesion coefficient and vary around the maximum value.

[0104] See Figure 5 203 shows a simulated braking operation using the anti-lock braking control method of an embodiment of the present invention, simulating an initial vehicle speed of 80 km / h on a wet asphalt road. 203a represents the simulated vehicle speed (Vehicle) and wheel speed (Wheel), 203b represents the braking distance, 203c shows the changes in the maximum adhesion coefficient (Maximum) and the real-time adhesion coefficient (Real-time), and 203d represents the braking torque. It can be seen that for braking on a wet asphalt road, the anti-lock braking control method of the present invention can force the real-time adhesion coefficient to always approach the maximum adhesion coefficient and vary around the maximum value.

[0105] Likewise, Figure 6 The simulation shows the braking situation on the snowy road with an initial speed of 45 km / h. Figure 7 In the simulation of braking on an icy road at an initial speed of 35 km / h, the anti-lock braking control method of the present invention can force the real-time adhesion coefficient to always be close to the maximum adhesion coefficient and vary around the maximum value.

[0106] Example 4

[0107] like Figure 8 As shown, this embodiment provides an anti-lock braking control system 300, including an electronic control unit 310 and a brake control unit 320. The electronic control unit 310 is configured to store a computer program. When the program is executed, it implements the anti-lock braking control method shown in the above embodiments and outputs a brake control signal corresponding to the first braking torque or the second braking torque. The brake control unit 320 is configured to receive the brake control signal from the electronic control unit 310 and control the braking device on the vehicle to generate a braking torque corresponding to the brake control signal. The braking torque acts on the wheels to achieve anti-lock braking.

[0108] In other possible embodiments, the wheel angular acceleration can be calculated by detecting continuous wheel speed. The anti-lock braking control system 300 may further include a wheel speed sensor, which is configured to be connected to the electronic control unit to detect the wheel speed and send it to the electronic control unit 310 to calculate the wheel angular acceleration.

[0109] Example 5

[0110] like Figure 9 and Figure 10 Figure 1 shows the overall structure of an electromechanical brake device 100 according to the present invention, comprising a brake 101, a lever structure 102, a brake bracket 103, and a brake wedge 104. Brake 101 is secured to brake bracket 103 via a first fixing member 105 and is connected to brake wedge 104 via lever structure 102. Braking force from brake 101 drives lever structure 102 to rotate relative to brake bracket 103.

[0111] One side of the brake wedge 104 contacts the first brake pad, and the other side is slidably connected to the brake caliper 106. The brake caliper 106 is fastened to the brake bracket 103 through the second fixing member 110. A second brake pad is arranged between the brake caliper 106 and the brake wedge 104, and the brake disc is arranged between the first brake pad and the second brake pad.

[0112] The braking force acting on the brake 101 is transmitted to the brake wedge 104 through the lever structure 102. The brake wedge 104 squeezes the first brake pad under the action of the force, causing the first brake pad and the second brake pad to move toward each other and contact the brake disc or move in the opposite direction away from the brake disc.

[0113] Figure 11 yes Figure 9 A top view of the braking device is shown, Figure 12 yes Figure 11Cross-sectional view taken along the AA direction. The lever structure 102 includes a first end 102a, a second end 102b, and a third end 102c. The first end 102a and the second end 102b are pivotally connected to the brake 101 via a first connecting member and a second connecting member, respectively. The third end 102c is pivotally connected to the brake wedge 104 via a third connecting member. The first end 102a and the third end 102c pivot on the second connecting member as the brake 101 moves. The pivoting of the third end 102c drives the brake wedge 104 to slide relative to the brake caliper 106.

[0114] In a possible design, in order to facilitate force transmission, the distance between the first end 102a and the second end 102b is greater than the distance between the second end 102b and the third end 102c.

[0115] In a possible design, the brake 101 includes a frame 101a, a stator 101b and a mover 101c. The stator 101b is fixed on the frame 101a and is arranged around the outside of the mover 101c. The mover 101c is pivotally connected to the first end 102a of the lever structure 102 through a first connecting member. When braking force is applied, the mover 101c moves linearly in the vertical direction, driving the first end 102a of the lever structure 102 to pivot on the second connecting member.

[0116] The present invention does not limit the specific structures of the first fixing member 105, the second fastener 110, the first connecting member, the second connecting member and the third connecting member mentioned above. Without departing from the technical concept of the present invention, those skilled in the art can adopt connecting members and connection methods commonly used in mechanical design, such as detachable connections or fixed connections, and for example, using bolts, sleeves, rivets, etc.

[0117] See Figure 13 , which is an exploded diagram of the coordination relationship between the various components of the electromechanical braking device provided in this embodiment.

[0118] The fixing member 105 includes a first bolt 105 a and a second bolt 105 b , which fastens the frame 101 a of the brake 101 to the brake bracket 103 .

[0119] The first connecting member includes a first pin 107a, a second pin 107b, a first set 107c and a second set 107d. The first pin 107a connects the first end of the first set 107c and the first end of the second set 107d to the mover 101c, and the second pin 107b connects the second end of the first set 107c and the second end of the second set 107d to the first end 102a of the lever structure 102. The first set 107c and the second set 107d can pivot on the first pin 107a and the second pin 107b.

[0120] The second connecting member includes a third pin 108, which connects the second end 102b of the lever structure 102 to the frame 101a, so that the second end 102b of the lever structure 102 can pivot on the third pin 108, and the first end 102a of the lever structure 102 can pivot on the third pin 108 along with the linear movement of the mover 101c.

[0121] The third connecting member includes a fourth pin 109a, a fifth pin 109b, a third kit 109c and a fourth kit 109d. The fourth pin 109a connects the first end of the third kit 109c and the first end of the fourth kit 109d to the third end 102c of the lever structure 102. The fifth pin 109b connects the second end of the third kit 109c and the second end of the fourth kit 109d to the brake wedge 104. The third kit 109c and the fourth kit 109d can pivot on the fourth pin 109a and the fifth pin 109b, and the third end 102c of the lever structure 102 can pivot on the third pin 108.

[0122] The second fastener 110 includes a third bolt 110a, a fourth bolt 110b, a first guide rod 110c and a second guide rod 110d. The third bolt 110a and the fourth bolt 110b fasten the brake caliper 106 with the first guide rod 110c and the second guide rod 110d. The first guide rod 110c and the second guide rod 110d are inserted into the brake bracket 103 and can move linearly.

[0123] The brake caliper 106 has a U-shaped groove, with a first end 106a of the caliper 106 slidingly contacting a first side of the brake wedge 104. The second side of the brake wedge 104 contacts a first brake pad 111. The second end 106b of the caliper 106 contacts a second brake pad 112. The brake disc 113 is disposed between the first brake pad 111 and the second brake pad 112. The brake wedge 104 can move linearly due to the pivoting of the third end 102c of the lever structure 102.

[0124] Based on the above structure, the force transmission process of the electromechanical brake device is described below, and the principle of braking by using the brake device is further explained.

[0125] When the driver steps on the pedal to brake, the electromagnetic force acting on the mover 101c is directed downward, and the mover 101c generates a first force through the first connecting member, which acts on the first end 102a of the lever structure 102, and the mover 101c moves linearly downward. Under the action of the first force, the first end 102a of the lever structure 102 pivots clockwise on the third pin 108. Therefore, the first connecting member converts the linear motion of the mover 101c into a rotational motion of the first end 102a of the lever 102.

[0126] The first force is transmitted through lever 102 and converted into a second force applied to third end 102c of lever 102, causing third end 102c of lever 102 to pivot clockwise on third pin 108. Because the distance between first end 102a and second end 102b is greater than the distance between second end 102b and third end 102c, the magnitude of the second force is significantly greater than the magnitude of the first force. The third connecting member converts the second force into a third force, which is applied to brake wedge 104. The third force is directed upward, causing brake wedge 104 to move upward. Thus, the third connecting member converts the rotational motion of third end 102c of lever 102 into linear motion of brake wedge 104.

[0127] The upward movement of brake wedge 104 generates a fourth force, a normal force, acting to the left on first brake pad 111. A counterforce to the fourth force, the fifth force, acts to the right on the inner side of first end 106a of brake caliper 106. Consequently, first brake pad 111 moves leftward and brake caliper 106 moves rightward. Through brake caliper 106, the fifth force is converted into a sixth force, a normal force acting to the right, acting on second brake pad 112. The fourth force is equal in magnitude to the sixth force but opposite in direction.

[0128] Under the action of the fourth and sixth forces, the first and second brake pads 111, 112 move toward each other toward the brake disc 113 disposed between them until they contact the brake disc 113. The fourth force is converted by the first brake pad 111 into a seventh force acting on the first side of the brake disc 113, a normal force directed to the left. The sixth force is converted by the second brake pad 112 into an eighth force acting on the second side of the brake disc 113, a normal force directed to the right. The seventh and eighth forces are equal in magnitude. Therefore, the seventh force generates a first friction force between the first brake pad 111 and the brake disc 113, while the eighth force generates a second friction force between the second brake pad 112 and the brake disc 113. The first and second friction forces generate a friction torque, i.e., a braking torque, in the opposite direction of the rotation of the brake disc 113, thereby stopping the rotation of the brake disc 113.

[0129] On the contrary, if the direction of the electromagnetic force acting on the mover 101c is upward, the mover 101c moves upward, and the first end 102a of the lever 102 rotates counterclockwise on the third pin 108, and the third end 102c pivots counterclockwise on the third pin 108, which causes the brake wedge 104 to move downward, the first brake pad 111 and the second brake pad 112 are released, and the braking is terminated.

[0130] When the electromechanical brake device is applied to the braking system of a vehicle, Figure 14As shown in the structural diagram, when pedal 114 is depressed, pedal 114 outputs a signal voltage to the brake control unit (ACU) 115 of the braking device. Power supply 116 supplies power to the brake control unit 115 and brake 101. The magnitude of the signal voltage varies with the angle at which pedal 114 is depressed. Force transmission is accomplished in components 102-110 of the electromechanical braking device, causing the first brake pad 111 and the second brake pad 112 to move toward the brake disc 113 until they contact the brake disc 113. The normal force applied to the first brake pad 111 and the second brake pad 112 varies with the electrical signal output by the pedal, generating friction between the first brake pad 111 and the second brake pad 112 and the brake disc 113, causing the rotating brake disc 113 to stop.

[0131] If the pedal 114 is released, the signal voltage output by the pedal 114 decreases to a minimum value, so the ACU 115 controls the brake 101 to output electromagnetic force in the opposite direction, so that the mover 101c of the brake 101 moves linearly in another direction, thereby releasing the first brake pad 111 and the second brake pad 112, and terminating the braking.

[0132] When the electromechanical brake device is used to implement the anti-lock brake control method provided in the above embodiment, a conversion relationship between the signal voltage and the braking torque can be established. Here, assuming that the angle of the brake wedge 104 is α, the signal voltage V in and braking torque T bw The relationship is as follows:

[0133]

[0134]

[0135] Among them, μ pd Indicates the friction coefficient between the brake pad and the brake disc, r p Indicates the average radius of the brake pad, L r represents the distance between the first end 102a and the second end 102b of the lever 102, L l represents the distance between the second end 102 b and the third end 102 c of the lever 102 , and represents the friction coefficient between the first brake pad 111 and the brake wedge 104 .

[0136] Example 6

[0137] See Figure 15This embodiment provides a vehicle 400 , wherein 401-404 represent wheels, 405-408 represent electromechanical brake devices according to an embodiment of the present invention, 409-412 represent wheel speed sensors, 413-416 represent brake control units (ACUs), 417 represents a brake pedal, and 418 represents an electronic control unit (ECU) for an anti-lock braking control system according to an embodiment of the present invention. The system is installed with a program for implementing the anti-lock braking control method according to an embodiment of the present invention. During a braking operation, ECU 418 receives the wheel speeds measured by sensors 409-412, executes the control algorithm of the anti-lock braking control method, and outputs brake control signals to ACUs 413-416, which control brake devices 405-408 to generate the desired braking torque to maximize the adhesion and adhesion coefficient of the four wheels.

[0138] It is understood that the electromechanical braking device provided in each embodiment of the present invention can be integrated into one device on a vehicle, or an independent braking device can be provided for each wheel, and is not limited to Figure 15 The situation shown.

[0139] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0140] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An anti-lock braking control method, characterized in that: This is accomplished through successive control cycles, each cycle consisting of a deceleration phase and an acceleration phase. The control method includes: The vehicle triggers anti-lock braking and enters the deceleration phase. The wheels decelerate under the action of the first braking torque. The calculation of the first braking torque includes: According to the first braking torque of the previous control cycle and the wheel angular acceleration reference value, the relationship between the first braking torques of two adjacent control cycles is established as follows: ； in, Indicates the The first braking torque of a control cycle, Indicates the The first braking torque of a control cycle, represents the differential constant, Indicates the The wheel angular acceleration reference value of a control cycle, Indicates the target value of the wheel angular acceleration during the wheel deceleration stage; When the wheel angular acceleration reaches the local maximum value of the angular acceleration in the deceleration phase of the current control cycle, the ratio of the adhesion force to the adhesion coefficient reaches the maximum value, the wheel stops decelerating and enters the acceleration phase; The wheel accelerates under the action of the second braking torque. When the wheel angular acceleration reaches the wheel angular acceleration reference value of the current control cycle, the ratio of adhesion to adhesion coefficient reaches the defined value, the wheel stops accelerating, and enters the next control cycle.

2. The anti-lock braking control method according to claim 1, characterized in that: The calculation of the second braking torque includes: The second braking torque of the current control cycle is calculated according to the second braking torque of the previous control cycle and the local maximum value of the angular acceleration in the deceleration phase of the current control cycle.

3. The anti-lock braking control method according to claim 2, characterized in that: The calculation of the second braking torque includes: According to the second braking torque of the previous control cycle and the local maximum value of angular acceleration in the deceleration phase of the current control cycle, the relationship between the second braking torques of two adjacent control cycles is established as follows: ； in, Indicates the The second braking torque of the control cycle, Indicates the The second braking torque of the control cycle, represents the differential constant, Indicates the The local maximum value of angular acceleration during the wheel deceleration phase of a control cycle, Indicates the target value of the wheel angular acceleration during the wheel acceleration phase.

4. The anti-lock braking control method according to claim 1, wherein: The calculation of the wheel angular acceleration reference value is as follows: ； in, Indicates the The wheel angular acceleration reference value of a control cycle, Indicates the attenuation coefficient of the wheel angular acceleration during the wheel acceleration phase, Indicates the The local maximum value of angular acceleration during the wheel acceleration phase of a control cycle.

5. The anti-lock braking control method according to claim 1, wherein: The method comprises: The relationship between wheel angular acceleration and adhesion is established as follows ； in, , , Indicates adhesion, is the wheel angular acceleration, represents the moment of inertia of the wheel, represents the wheel radius, Indicates braking torque; The relationship between wheel angular acceleration and adhesion coefficient is established as follows ； in, , represents the adhesion coefficient, Indicates the vertical force acting on the wheel.

6. The anti-lock braking control method according to claim 1, wherein: The wheel angular acceleration is calculated based on the continuously measured wheel speed.

7. An anti-lock braking control system, characterized in that: The method for implementing the anti-lock braking control method according to any one of claims 1 to 6 comprises: an electronic control unit configured to store a computer program, wherein when the program is executed, the anti-lock braking control method according to any one of claims 1 to 6 is implemented, and a braking control signal corresponding to the first braking torque or the second braking torque is output; The brake control unit is configured to receive the brake control signal from the electronic control unit and to control the brake device to generate a braking torque corresponding to the brake control signal.

8. The anti-lock braking control system according to claim 7, wherein: The system further includes a wheel speed sensor configured to be connected to the electronic control unit, for detecting wheel speed and sending the speed to the electronic control unit to calculate wheel angular acceleration.

9. An electromechanical braking device, characterized in that: The method for implementing the anti-lock braking control method according to any one of claims 1 to 6 comprises: The brake is fastened to the brake bracket via a first fixing member and is connected to the brake wedge via a lever structure, wherein the brake drives the lever structure to rotate relative to the brake bracket under the action of a braking force; One side of the brake wedge contacts the first brake pad, and the other side is slidably connected to the brake caliper, the brake caliper is fastened to the brake bracket via a second fixing member, a second brake pad is arranged between the brake caliper and the brake wedge, and a brake disc is arranged between the first brake pad and the second brake pad; The braking force acting on the brake is transmitted to the brake wedge through the lever structure. The brake wedge squeezes the first brake pad under the action of the force, so that the first brake pad and the second brake pad move toward each other and contact the brake disc or move in the opposite direction away from the brake disc.

10. The electromechanical brake device according to claim 9, characterized in that: The lever structure includes a first end, a second end, and a third end; The first end and the second end are pivotally connected to the brake via a first connecting member and a second connecting member respectively, and the third end is pivotally connected to the brake wedge via a third connecting member. The first end and the third end pivot on the second connecting member as the brake moves, and the pivoting of the third end drives the brake wedge to slide relative to the brake caliper.

11. The electromechanical brake device according to claim 10, characterized in that: In the lever structure, a distance between the first end and the second end is greater than a distance between the second end and the third end.

12. The electromechanical brake device according to claim 10, characterized in that: The brake comprises a frame, a stator and a mover; The stator is fixed on the frame and is arranged around the outside of the mover; The mover is pivotally connected to the first end of the lever structure through a first connecting member. When a braking force is applied, the mover moves in a vertical direction, driving the first end of the lever structure to pivot on the second connecting member.

13. A vehicle, characterized in that: An anti-lock braking control system according to any one of claims 7 to 8 is installed thereon, for implementing the anti-lock braking control method according to any one of claims 1 to 6, and the vehicle is provided with at least one electromechanical braking device according to any one of claims 9 to 12.

14. The vehicle according to claim 13, characterized in that The vehicle has a plurality of wheels, and each wheel is provided with an electromechanical braking device according to any one of claims 9 to 12.

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