A vehicle braking device and a braking system

Abstract

The present invention provides a service braking device and a braking system, belonging to the technical field of vehicle braking; the service braking device includes: an EPB caliper and a brake disc, the brake disc is connected to the drive shaft through a flange, and the EPB caliper is connected to the reducer housing through a caliper bracket; the EPB controller is electrically connected to the EPB caliper; the brake disc detection module is used to detect the parameters of the brake disc; the EPB controller is electrically connected to the EPB caliper and the brake disc detection module respectively. The present invention solves the following problems existing in the existing electronic parking brake system / device (such as CN108001437B - Vehicle control device and its control method): when determining the target braking force, the influence of the brake disc parameters on the braking force is not considered (the brake disc parameters such as the surface temperature of the brake disc, when the surface temperature of the brake disc is high, the friction coefficient between the brake pads and the brake disc will decrease), which affects the reliability of the braking force determination.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle braking, and particularly relates to a service braking device and a braking system. Background Art

[0002] Vehicles are generally equipped with an electronic parking brake system, abbreviated as EPB, full name Electrical Park Brake. The electronic parking brake system controls parking braking through electronic circuits, with the same function as a mechanical lever handbrake, and the electronic parking brake system will automatically release when starting by stepping on the accelerator.

[0003] In existing electronic parking brake systems / devices (such as CN108001437B - Vehicle control device and its control method), there are the following problems:

[0004] When determining the target braking force, the influence of brake disc parameters on the braking force is not considered (brake disc parameters such as the surface temperature of the brake disc. When the surface temperature of the brake disc is high, the friction coefficient between the brake pads and the brake disc will decrease), affecting the reliability of braking force determination. Summary of the Invention

[0005] The present invention provides a service braking device and a braking system to solve the technical problems raised in the above background art.

[0006] To solve the above technical problems, the present invention discloses a service braking device, including:

[0007] An EPB caliper and a brake disc. The brake disc is connected to the drive shaft through a flange, and the EPB caliper is connected to the reducer housing through a caliper bracket;

[0008] An EPB controller, electrically connected to the EPB caliper;

[0009] A brake disc detection module: used to detect the parameters of the brake disc;

[0010] The EPB controller is electrically connected to the EPB caliper and the brake disc detection module respectively. The EPB controller includes:

[0011] A braking force determination module: used to determine the target braking force for the current braking of the brake disc corresponding to the current EPB caliper based on the detection result of the brake disc detection module corresponding to the brake disc corresponding to the current EPB caliper, the historical braking heat generation parameters of the brake disc corresponding to the current EPB caliper, and the temperature weight of the brake disc corresponding to the current EPB caliper;

[0012] A braking control module: used to control the EPB motor of the current EPB caliper to work for the current braking of the brake disc corresponding to the current EPB caliper based on the target braking force for the current braking of the brake disc corresponding to the current EPB caliper.

[0013] Preferably, the EPB caliper includes: a caliper body, an EPB screw and nut, and an actuator assembly. The actuator assembly is configured to drive the rotation of the EPB screw in the EPB screw and nut, so that the EPB nut in the EPB screw and nut drives the caliper body to clamp or release the brake disc. The actuator assembly is electrically connected to the EPB controller; the actuator assembly includes: an EPB motor and a transmission mechanism. The EPB motor drives the rotation of the EPB screw through the transmission mechanism.

[0014] Preferably, the parameters of the brake disc include: the surface temperature of the brake disc and the rotational speed of the brake disc.

[0015] Preferably, the braking force determination module includes:

[0016] A required braking force determination unit: configured to determine the initial required braking force for the current braking of the brake disc corresponding to the current EPB caliper;

[0017] A first acquisition unit: configured to acquire the surface temperature and rotational speed of the brake disc corresponding to the current EPB caliper before the current braking;

[0018] A second acquisition unit: configured to acquire the first target historical data of the target brake disc corresponding to the initial required braking force for the current braking of the brake disc corresponding to the current EPB caliper, and determine the braking heat generation amount of the brake disc after each braking in the first target historical data; the historical braking force of the EPB caliper corresponding to the first target historical data on the corresponding brake disc is within a first preset range of the initial required braking force for the current braking of the brake disc corresponding to the current EPB caliper, and the initial speed of the brake disc before the historical braking of the EPB caliper corresponding to the first target historical data on the corresponding brake disc is within a second preset range of the rotational speed of the brake disc corresponding to the current EPB caliper before the current braking; the target brake disc corresponding to the brake disc corresponding to the current EPB caliper is the same type of brake disc as the brake disc corresponding to the current EPB caliper;

[0019] A first calculation unit: configured to calculate the target braking force for the current braking of the brake disc corresponding to the current EPB caliper based on the first acquisition unit and the second acquisition unit.

[0020] Preferably, the first calculation unit calculates based on the following formula:

[0021] ;

[0022] is the target braking force for the current braking of the brake disc corresponding to the current EPB caliper; is the initial required braking force for the current braking of the brake disc corresponding to the current EPB caliper; The average braking heat generation of the brake disc after each braking in the first target historical data of the target brake disc corresponding to the initial required braking force of the current braking of the brake disc corresponding to the current EPB caliper; The surface temperature of the brake disc corresponding to the current EPB caliper before the current braking; The temperature coefficient of the brake disc corresponding to the current EPB caliper; The specific heat capacity of the brake disc corresponding to the current EPB caliper; The weight of the brake disc corresponding to the current EPB caliper; 、 The first temperature weight of the brake disc corresponding to the current EPB caliper and the second temperature weight of the brake disc corresponding to the current EPB caliper, respectively; The first reference temperature.

[0023] Preferably, it further includes:

[0024] The EPB motor detection module: used to detect the parameters of the EPB motor in the EPB caliper;

[0025] The braking control module includes:

[0026] The braking current determination unit: used to determine the target braking current of the EPB motor of the current EPB caliper for the current braking based on the target braking force of the current braking of the brake disc corresponding to the current EPB caliper and the detection result of the EPB motor detection module corresponding to the EPB motor of the current EPB caliper;

[0027] The control unit: used to control the operation of the EPB motor of the current EPB caliper to brake the brake disc corresponding to the current EPB caliper for the current braking based on the target braking current of the current braking of the EPB motor of the current EPB caliper.

[0028] Preferably, the parameters of the EPB motor include: the surface temperature of the armature winding of the EPB motor.

[0029] Preferably, it further includes:

[0030] The heat generation detection module: used to periodically determine the heat generation rate of the armature winding of the EPB motor based on the detection of the armature winding of the EPB motor;

[0031] The braking current determination unit includes:

[0032] The first determination subunit: used to determine the first torque corresponding to the current braking of the EPB motor of the current EPB caliper;

[0033] The first acquisition subunit: used to acquire the surface temperature of the armature winding of the EPB motor of the current EPB caliper before the current braking;

[0034] The second acquisition subunit is configured to acquire the temperature-torque constant change curve of the EPB motor of the current EPB caliper; in the temperature-torque constant change curve of the EPB motor, the abscissa is the temperature of the EPB motor, and the ordinate is the torque constant of the EPB motor;

[0035] The first calculation subunit is configured to determine the first ordinate of the temperature-torque constant change curve of the EPB motor of the current EPB caliper corresponding to the surface temperature before the current braking of the armature winding of the EPB motor of the current EPB caliper, and determine the first current corresponding to the current braking of the EPB motor of the current EPB caliper based on the first ordinate and the first torque;

[0036] The second determination subunit is configured to determine the total historical heat generation of the EPB motor of the current EPB caliper during the braking process when the historical braking current of the EPB motor of the current EPB caliper is within a preset range of the first current;

[0037] The second calculation subunit is configured to correct the first current based on the second determination subunit to obtain the target current corresponding to the current braking of the EPB motor of the current EPB caliper.

[0038] The present invention also discloses a service braking system, including the service braking device described above.

[0039] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0040] 1. Determine the first target historical data matching the brake disc corresponding to the current EPB caliper based on the detection result of the brake disc detection module corresponding to the brake disc corresponding to the current EPB caliper, determine the historical braking heat generation parameter of the brake disc corresponding to the current EPB caliper based on the first target historical data matching the brake disc corresponding to the current EPB caliper (specifically, the braking heat generation amount of the brake disc after each historical braking in the corresponding first target historical data), and correct the initial required braking force of the current braking of the brake disc corresponding to the current EPB caliper based on the historical braking heat generation parameter of the brake disc corresponding to the current EPB caliper to obtain the target braking force of the current braking of the brake disc corresponding to the current EPB caliper;

[0041] It is realized that the initial required braking force of the current braking of the brake disc corresponding to the current EPB caliper is appropriately increased in consideration of the heating temperature rise state of the brake disc to obtain the target braking force of the current braking of the brake disc corresponding to the current EPB caliper, ensuring the reliability of the current braking of the brake disc corresponding to the current EPB caliper.

[0042] 2. The heat generation temperature change performance of different types of brake discs is different. Different temperature weights are determined based on different types of brake discs, ensuring the reliable determination of the target braking force.

[0043] 3. The present invention solves the following problems in the prior art in the existing electronic parking brake system / device (such as CN108001437B - Vehicle control device and its control method):

[0044] When determining the target braking force, the influence of brake disc parameters on the braking force is not considered (brake disc parameters such as the surface temperature of the brake disc. When the surface temperature of the brake disc is high, the friction coefficient between the brake pad and the brake disc will decrease), affecting the reliability of the determination of the braking force. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0046] Figure 1 is a schematic structural diagram of the present invention;

[0047] Figure 2 is a schematic block diagram of some components of the present invention;

[0048] Figure 3 is a schematic structural diagram of the caliper bracket of the present invention.

[0049] In the figure: 1, EPB caliper; 2, brake disc; 3, transmission shaft; 4, caliper bracket; 5, reducer housing. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the present invention with reference to the drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0051] Embodiment 1:

[0052] A driving brake device provided by an embodiment of the present invention, as Figures 1 - 3 shown, includes:

[0053] EPB caliper 1 and brake disc 2, the brake disc 2 is connected to the drive shaft 3 through a flange (can be fastened by screws), and the EPB caliper 1 is connected to the reducer housing 5 through a caliper bracket 4;

[0054] An EPB controller, the EPB controller is electrically connected to the EPB caliper 1;

[0055] Brake disc 2 detection module: used to detect the parameters of the brake disc 2;

[0056] The EPB controller is electrically connected to the EPB caliper 1 and the brake disc 2 detection module respectively;

[0057] The EPB caliper 1 includes: a caliper body, an EPB screw and nut, and an actuator assembly. The actuator assembly is used to drive the rotation of the EPB screw in the EPB screw and nut, so that the EPB nut in the EPB screw and nut drives the caliper body to clamp or release the brake disc 2. The actuator assembly is electrically connected to the EPB controller; The actuator assembly includes: an EPB motor and a transmission mechanism. The EPB motor drives the EPB screw to rotate through the transmission mechanism (when the EPB motor rotates forward, the caliper body clamps the brake disc to achieve braking. When the EPB motor rotates backward, the brake disc is released and the braking is released). The above structure and working principle of the EPB caliper are all prior arts, and the existing EPB caliper can be referred to;

[0058] In the present invention, the mass of the EPB caliper is about 5 kg, and a set of braking systems are installed on the front and rear vehicles to control it. The control panel needs to reserve an EPB switch for controlling the EPB.

[0059] The EPB caliper is controlled by the EPB controller, and the EPBs of the front and rear vehicles both use the EPB switch button as the signal input.

[0060] The EPB controller communicates with the VCU through CAN. The EPB controller sends the EPB status signal to the whole vehicle and receives the required vehicle status information from the bus;

[0061] The working voltage of the EPB caliper is 12V, and a DC transformer is required;

[0062] When the vehicle breaks down and the EPB parking needs to be released, the on-vehicle battery or an external power supply is used to supply power to the EPB controller, and then the parking can be released through the EPB switch to achieve a non-powered trailer.

[0063] The EPB is controlled by a button, and only through the button can the parking be achieved;

[0064] If the EPB is damaged in the parking state, the EPB motor can be reversed through an external power supply to release it;

[0065] Among them, the EPB controller includes:

[0066] Braking force determination module: used to determine the target braking force for the current braking of the brake disc 2 corresponding to the current EPB caliper based on the detection result of the brake disc 2 detection module corresponding to the current EPB caliper and the historical braking heat generation parameters of the brake disc 2 corresponding to the current EPB caliper;

[0067] Braking current determination module: used to determine the target braking current for the current braking of the EPB motor of the current EPB caliper based on the target braking force for the current braking of the brake disc 2 corresponding to the current EPB caliper and the detection result of the EPB motor detection module corresponding to the EPB motor of the current EPB caliper;

[0068] Control module, used to control the operation of the EPB motor of the current EPB caliper for the current braking of the brake disc 2 corresponding to the current EPB caliper based on the target braking current for the current braking of the EPB motor of the current EPB caliper.

[0069] In the present invention, the maximum clamping force of the EPB motor is 14 KN; the operating temperature of the EPB caliper 1 is -40°C - 120°C; the positive and negative pin feet of the EPB motor are connected to the EPB controller through the EPB wiring harness.

[0070] The parameters of the brake disc 2 include: the surface temperature of the brake disc 2 and the rotational speed of the brake disc 2;

[0071] The parameters of the EPB motor include: the surface temperature of the EPB motor and the operating duration of the EPB motor.

[0072] The braking force determination module includes:

[0073] Required braking force determination unit: used to determine the initial required braking force for the current braking of the brake disc 2 corresponding to the current EPB caliper (which can be determined based on the prior art without considering the heat generation of the brake disc 2, such as determined according to the vehicle parking environment (the target braking force determined with reference to CN119459639 A));

[0074] First acquisition unit: used to acquire the surface temperature and rotational speed of the brake disc 2 corresponding to the current EPB caliper before the current braking;

[0075] The second acquisition unit: configured to acquire first target historical data of a target brake disc corresponding to the initial required braking force of the current braking of the brake disc 2 corresponding to the current EPB caliper, and determine the braking heat generation amount of the brake disc 2 after each braking in the first target historical data; the historical braking force of the corresponding brake disc 2 by the EPB caliper 1 corresponding to the first target historical data is within a first preset range of the initial required braking force of the current braking of the brake disc 2 corresponding to the current EPB caliper, and the initial speed of the brake disc 2 before the historical braking of the corresponding brake disc 2 by the EPB caliper 1 corresponding to the first target historical data is within a second preset range of the rotational speed before the current braking of the brake disc 2 corresponding to the current EPB caliper; the target brake disc corresponding to the brake disc 2 corresponding to the current EPB caliper is the same type of brake disc 2 as the brake disc 2 corresponding to the current EPB caliper;

[0076] The first calculation unit: configured to calculate the target braking force of the current braking of the brake disc 2 corresponding to the current EPB caliper based on the first acquisition unit and the second acquisition unit.

[0077] The first calculation unit calculates based on the following formula:

[0078] ;

[0079] is the target braking force of the current braking of the brake disc 2 corresponding to the current EPB caliper; is the initial required braking force of the current braking of the brake disc 2 corresponding to the current EPB caliper; is the average value of the braking heat generation amount of the brake disc after each braking (determined based on the prior art) in the first target historical data of the target brake disc corresponding to the initial required braking force of the current braking of the brake disc 2 corresponding to the current EPB caliper; is the surface temperature of the brake disc 2 corresponding to the current EPB caliper before the current braking; is the temperature coefficient of the brake disc 2 corresponding to the current EPB caliper (the value ranges from 2 - 5×10 -6 , with the unit of 1 / ℃); is the specific heat capacity of the brake disc 2 corresponding to the current EPB caliper; is the weight of the brake disc 2 corresponding to the current EPB caliper; 、 are respectively the first temperature weight and the second temperature weight of the brake disc 2 corresponding to the current EPB caliper (the values respectively range from greater than 0 to less than 1); is the first reference temperature (the reference temperature when calculating the initial required braking torque of the brake disc 2, and the first reference temperature can also be set to 100℃);

[0080] , It can also be determined based on the first test. The first test is as follows: use an EPB caliper for the standard braking force control test (the standard braking force can be 0.5 - 1 times the rated braking force of the corresponding EPB caliper) to perform a braking test on the corresponding test brake disc of the current EPB caliper (the corresponding test brake disc of the current EPB caliper is of the same type as the brake disc corresponding to the current EPB caliper. The same type means the same material and the same structure). During the braking test, repeatedly obtain the surface temperature of the corresponding test brake disc of the current EPB caliper, and construct a time - surface temperature change curve of the corresponding test brake disc of the current EPB caliper (the abscissa is time, and the ordinate is the surface temperature of the corresponding test brake disc of the current EPB caliper), and determine the initial ordinate of the time - surface temperature change curve of the corresponding test brake disc of the current EPB caliper. and the end ordinate , and divide the time - surface temperature change curve of the corresponding test brake disc of the current EPB caliper into a first sub - curve segment and a second sub - curve segment. The ratio of all the ordinates of the first sub - curve segment to the initial ordinate ranges from 1 to 1.2, and the ratio of all the ordinates of the second sub - curve segment to the end ordinate ranges from 0.8 to 1. Determine the sum B of the abscissa lengths of all the first sub - curve segments of the time - surface temperature change curve of the corresponding test brake disc of the current EPB caliper, and determine the sum C of the abscissa lengths of all the second sub - curve segments of the time - surface temperature change curve of the corresponding test brake disc of the current EPB caliper. ,

[0081] , where D is the sum of the abscissa lengths of the time - surface temperature change curve of the corresponding test brake disc of the current EPB caliper except for the first sub - curve segment and the second sub - curve segment). The heat - generating temperature change performance of different types of brake discs is different (the temperature change state is different between the initial ordinate and the end ordinate of the time - surface temperature change curve of the corresponding test brake disc of the current EPB caliper). Different temperature weights are determined based on different types of brake discs.

[0082] Before the service of the vehicle braking device, the present invention can obtain the initial required braking force in common use and the braking heat generation at the initial speed of the common brake disc through tests as the initial historical data;

[0083] The beneficial effects of the above technical solutions are as follows:

[0084] 1. Determine the first target historical data matching the brake disc 2 corresponding to the current EPB caliper based on the detection result of the brake disc 2 detection module corresponding to the current EPB caliper. Determine the historical braking heat generation parameter of the brake disc 2 corresponding to the current EPB caliper based on the first target historical data matching the brake disc 2 corresponding to the current EPB caliper (specifically, the braking heat generation amount of the brake disc 2 after each historical braking in the corresponding first target historical data). Modify the initial required braking force for the current braking of the brake disc 2 corresponding to the current EPB caliper based on the historical braking heat generation parameter of the brake disc 2 corresponding to the current EPB caliper to obtain the target braking force for the current braking of the brake disc 2 corresponding to the current EPB caliper;

[0085] It is realized that the initial required braking force for the current braking of the brake disc 2 corresponding to the current EPB caliper is appropriately increased considering the heat rise state of the brake disc to obtain the target braking force for the current braking of the brake disc 2 corresponding to the current EPB caliper, ensuring the reliability of the current braking of the brake disc 2 corresponding to the current EPB caliper.

[0086] 2. The heat generation temperature change performances of different types of brake discs 2 are different. Different temperature weights are determined based on different types of brake discs 2, ensuring the reliable determination of the target braking force.

[0087] 3. The present invention solves the following problems in the background technology: in the existing electronic parking brake system / device (such as CN108001437B - vehicle control device and its control method):

[0088] When determining the target braking force, the influence of brake disc 2 parameters on the braking force is not considered (brake disc 2 parameters such as the surface temperature of the brake disc 2. When the surface temperature of the brake disc 2 is high, the friction coefficient between the brake pad and the brake disc 2 will decrease), affecting the reliability of the determination of the braking force.

[0089] In Embodiment 2, on the basis of Embodiment 1, a vehicle braking device further includes:

[0090] EPB motor detection module: used to detect the parameters of the EPB motor in the EPB caliper 1;

[0091] The braking control module includes:

[0092] Braking current determination unit: used to determine the target braking current for the current braking of the EPB motor of the current EPB caliper based on the target braking force for the current braking of the brake disc 2 corresponding to the current EPB caliper and the detection result of the EPB motor detection module corresponding to the EPB motor of the current EPB caliper;

[0093] A control unit, configured to control an EPB motor of a current EPB caliper to operate for a current braking of a brake disc corresponding to the current EPB caliper based on a target braking current of a current braking of the EPB motor of the current EPB caliper.

[0094] The parameters of the EPB motor include: the surface temperature of the armature winding of the EPB motor.

[0095] Specifically, a service braking device further includes:

[0096] A heat generation detection module: configured to periodically determine a heat generation rate of the armature winding of the EPB motor based on a detection of the armature winding of the EPB motor.

[0097] The braking current determination unit includes:

[0098] A first determination subunit: configured to determine a first torque corresponding to a current braking of the EPB motor of the current EPB caliper.

[0099] A first acquisition subunit: configured to acquire a surface temperature of the armature winding of the EPB motor of the current EPB caliper before the current braking.

[0100] A second acquisition subunit: configured to acquire a temperature-torque constant change curve of the EPB motor of the current EPB caliper; in the temperature-torque constant change curve of the EPB motor, the abscissa is the temperature of the EPB motor, and the ordinate is the torque constant of the EPB motor.

[0101] A first calculation subunit: configured to determine a first ordinate of the temperature-torque constant change curve of the EPB motor of the current EPB caliper corresponding to the surface temperature of the armature winding of the EPB motor of the current EPB caliper before the current braking, and determine a first current corresponding to the current braking of the EPB motor of the current EPB caliper based on the first ordinate and the first torque.

[0102] A second determination subunit: configured to determine a historical total heat generation amount of the EPB motor of the current EPB caliper during a braking process when a historical braking current of the EPB motor of the current EPB caliper is within a preset range of the first current (the preset range of the first current is 0.95 times the first current to 1.05 times the first current).

[0103] A second calculation subunit: configured to correct the first current based on the second determination subunit to obtain a target current corresponding to the current braking of the EPB motor of the current EPB caliper.

[0104] The first determination subunit is calculated based on the following formula:

[0105] ;

[0106] r is the pitch diameter of the EPB screw of the current EPB caliper, is the helix angle of the EPB screw of the current EPB caliper, is the friction coefficient of the thread pair in the EPB screw sleeve of the current EPB caliper; is the friction coefficient between the brake pad and the brake disc in the caliper body of the current EPB caliper; i is the transmission ratio of the transmission mechanism in the actuator assembly of the current EPB caliper; tan represents the tangent; is the first torque corresponding to the current braking of the EPB motor of the current EPB caliper 1; is the target braking force of the current braking of the brake disc 2 corresponding to the current EPB caliper 1;

[0107] ;

[0108] Among them, is the surface temperature of the armature winding of the EPB motor of the current EPB caliper before the current braking, is in the temperature-torque constant change curve of the EPB motor of the current EPB caliper, corresponding to the ordinate corresponding thereto (the first ordinate); is the first current corresponding to the current braking of the EPB motor of the current EPB caliper (corresponding to the first ordinate);

[0109] ;

[0110] is the target braking current of the current braking of the EPB motor of the current EPB caliper (which can be the average current during the braking process); is the surface temperature of the armature winding of the EPB motor of the current EPB caliper before the current braking of the current EPB caliper, is the weight of the armature winding of the EPB motor of the current EPB caliper; is the specific heat capacity of the armature winding of the EPB motor of the current EPB caliper; M is the quantity of the historical total heat generation obtained by the second determination sub-unit; is the jth historical total heat generation obtained by the second determination sub-unit; is the heat generation rate of the armature winding of the EPB motor of the current EPB caliper obtained most recently before the current braking of the current EPB caliper, is the heat generation rate of the armature winding of the EPB motor of the current EPB caliper obtained most recently before the historical braking corresponding to the jth historical total heat generation obtained by the second determination sub-unit; In the temperature-torque constant change curve of the EPB motor of the current EPB caliper, it is related to The corresponding ordinate.

[0111] The beneficial effects of the above technical solution are as follows:

[0112] Based on the surface temperature of the armature winding of the EPB motor of the current EPB caliper before the current braking and the temperature-torque constant change curve of the EPB motor of the current EPB caliper, initially determine the first current that matches the target braking force of the current braking of the brake disc 2 corresponding to the current EPB caliper; then determine the historical heating parameter corresponding to the first current of the EPB motor of the current EPB caliper (that is, when the historical braking current of the EPB motor of the current EPB caliper is within the preset range of the first current, the historical total heat generation of the EPB motor of the current EPB caliper during the braking process), and correct the first current in combination with the historical heating parameter corresponding to the first current of the EPB motor of the current EPB caliper to obtain the target current corresponding to the current braking of the EPB motor of the current EPB caliper. The calculation is reliable, ensuring the selection of a suitable target current, thereby ensuring the braking effect of the present invention.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A service braking device, characterized in that, Including: An EPB caliper (1) and a brake disc (2), the brake disc (2) is flange-connected to a drive shaft (3), and the EPB caliper (1) is connected to a reducer housing (5) through a caliper bracket (4); An EPB controller, the EPB controller is electrically connected to the EPB caliper (1); A brake disc (2) detection module: used to detect parameters of the brake disc (2); The EPB controller is electrically connected to the EPB caliper (1) and the brake disc (2) detection module respectively, and the EPB controller includes: A braking force determination module: used to determine the target braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1) based on the detection result of the brake disc (2) detection module corresponding to the brake disc (2) corresponding to the current EPB caliper (1), the historical braking heat generation parameter of the brake disc (2) corresponding to the current EPB caliper (1), and the temperature weight of the brake disc (2) corresponding to the current EPB caliper (1); A braking control module: used to control the EPB motor of the current EPB caliper (1) to work for the current braking of the brake disc (2) corresponding to the current EPB caliper (1) based on the target braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1); The parameters of the brake disc (2) include: the surface temperature of the brake disc (2) and the rotational speed of the brake disc (2); The braking force determination module includes: A required braking force determination unit: used to determine the initial required braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1); A first acquisition unit: used to acquire the surface temperature and rotational speed of the brake disc (2) corresponding to the current EPB caliper (1) before the current braking; A second acquisition unit: used to acquire the first target historical data of the target brake disc corresponding to the initial required braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1), and determine the braking heat generation amount of the brake disc (2) after each braking in the first target historical data; the historical braking force of the EPB caliper (1) corresponding to the first target historical data on the corresponding brake disc (2) is within the first preset range of the initial required braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1), and the initial speed of the brake disc (2) before the historical braking of the EPB caliper (1) corresponding to the first target historical data is within the second preset range of the rotational speed of the brake disc (2) corresponding to the current EPB caliper (1) before the current braking; the target brake disc corresponding to the brake disc (2) corresponding to the current EPB caliper (1) is the same type of brake disc (2) as the brake disc (2) corresponding to the current EPB caliper (1); A first calculation unit: used to calculate the target braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1) based on the first acquisition unit and the second acquisition unit; The first calculation unit calculates based on the following formula: ； is the target braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1); is the initial required braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1); is the average value of the braking heat generation of the brake disc (2) after each braking in the first target historical data of the target brake disc corresponding to the initial required braking force for the current braking of the brake disc (2) corresponding to the current EPB caliper (1); is the surface temperature of the brake disc (2) corresponding to the current EPB caliper (1) before the current braking; is the temperature coefficient of the brake disc (2) corresponding to the current EPB caliper (1); is the specific heat capacity of the brake disc (2) corresponding to the current EPB caliper (1); is the weight of the brake disc (2) corresponding to the current EPB caliper (1); 、 are respectively the first temperature weight of the brake disc (2) corresponding to the current EPB caliper (1) and the second temperature weight of the brake disc (2) corresponding to the current EPB caliper (1); is the first reference temperature.

2. The vehicle braking device according to claim 1, wherein The EPB caliper (1) includes: a caliper body, an EPB screw and nut assembly, and an actuator assembly. The actuator assembly is used to drive the rotation of the EPB screw in the EPB screw and nut assembly, so that the EPB nut in the EPB screw and nut assembly drives the caliper body to clamp or release the brake disc (2). The actuator assembly is electrically connected to the EPB controller; the actuator assembly includes: an EPB motor and a transmission mechanism. The EPB motor drives the rotation of the EPB screw through the transmission mechanism.

3. A vehicle braking device according to claim 1, characterized in that, It further includes: The EPB motor detection module: used to detect the parameters of the EPB motor in the EPB caliper (1); The brake control module includes: The braking current determination unit: used to determine the target braking current of the current EPB motor of the current EPB caliper (1) for the current braking based on the target braking force of the current braking of the brake disc (2) corresponding to the current EPB caliper (1) and the detection result of the EPB motor detection module corresponding to the EPB motor of the current EPB caliper (1); The control unit: used to control the operation of the EPB motor of the current EPB caliper (1) to perform the current braking on the brake disc (2) corresponding to the current EPB caliper (1) based on the target braking current of the current braking of the EPB motor of the current EPB caliper (1).

4. The vehicle braking device according to claim 3, characterized in that The parameters of the EPB motor include: the surface temperature of the armature winding of the EPB motor.

5. The vehicle braking device according to claim 4, characterized in that It further includes: The heat generation detection module: used to periodically determine the heat generation rate of the armature winding of the EPB motor based on the detection of the armature winding of the EPB motor; The braking current determination unit includes: The first determination subunit: used to determine the first torque corresponding to the current braking of the EPB motor of the current EPB caliper (1); The first acquisition subunit: used to acquire the surface temperature of the armature winding of the EPB motor of the current EPB caliper (1) before the current braking; The second acquisition subunit: used to acquire the temperature-torque constant change curve of the EPB motor of the current EPB caliper (1); in the temperature-torque constant change curve of the EPB motor, the abscissa is the temperature of the EPB motor, and the ordinate is the torque constant of the EPB motor; The first calculation subunit: used to determine the first ordinate of the temperature-torque constant change curve of the EPB motor of the current EPB caliper (1) corresponding to the surface temperature of the armature winding of the EPB motor of the current EPB caliper (1) before the current braking, and determine the first current corresponding to the current braking of the EPB motor of the current EPB caliper (1) based on the first ordinate and the first torque; The second determination subunit: used to determine the total historical heat generation of the EPB motor of the current EPB caliper (1) during the braking process when the historical braking current of the EPB motor of the current EPB caliper (1) is within the preset range of the first current; The second calculation subunit: used to correct the first current based on the second determination subunit to obtain the target current corresponding to the current braking of the EPB motor of the current EPB caliper (1).

6. A vehicle braking system, characterized in that, It includes: A vehicle braking device according to any one of claims 1 to 5.

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