Standby braking system

Abstract

The utility model provides a standby braking system, which relates to the technical field of electric automobiles and comprises a current detection module, a fixed pulse time driving module, a fault signal output module, an actuator output switching module and an execution motor. The current detection module is connected with the fault signal output module; the current detection module, the fault signal output module, the fixed pulse time driving module, the actuator output switching module and the motor are connected in sequence; the current detection module is used for power supply and overcurrent protection of the standby braking system; the fixed pulse time driving module is used for outputting time-adjustable pulse square wave signals; and the fault signal output module is used for detecting external EHB power supply voltage and outputting an EHB fault signal to the whole vehicle. According to the utility model, the stability and maintainability of the system can be improved, and the probability of faults is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to electric automobile field, especially involves a standby braking system. BACKGROUND

[0002] The standby braking system is an emergency braking device that can ensure the vehicle to continue safe parking when the main braking system fails or malfunctions, and usually works with the main braking system. When the main braking system has problems, the standby braking system automatically switches to the standby power supply and controls the actuator to provide braking force, ensuring that the driver can safely stop the vehicle.

[0003] With the improvement of automobile electronicization and automation level, modern vehicles rely on complex electronic and electric braking systems. Once these systems fail or fail, it may cause serious safety accidents. The standby braking system can automatically switch to the standby power supply and drive the brake when the main braking system cannot work, ensuring that the vehicle can avoid accidents even if it fails at a critical moment.

[0004] However, the existing standby braking system may have response delay when switching power supply and controlling actuator. When power interruption or system failure occurs, it cannot provide sufficient braking force in time. When fault detection is performed, all types of voltage or current abnormalities cannot be comprehensively detected, resulting in failure to output fault signal or start standby braking in time when failure occurs. SUMMARY

[0005] In order to solve the technical problems that the existing standby braking system may have response delay when switching power supply and controlling actuator, cannot provide sufficient braking force in time when power interruption or system failure occurs, and cannot comprehensively detect all types of voltage or current abnormalities when fault detection is performed, resulting in failure to output fault signal or start standby braking in time when failure occurs, the utility model provides a standby braking system.

[0006] The technical scheme provided by the utility model embodiment is as follows:

[0007] The utility model embodiment provides a kind of standby braking system, comprising: current detection module, fixed pulse time driving module, fault signal output module, actuator output switching module and execution motor;

[0008] The current detection module is connected with the fault signal output module;

[0009] The current detection module, fixed pulse time driving module, fault signal output module, actuator output switching module and motor are sequentially connected;

[0010] The current detection module is used for power supply and overcurrent protection of the backup braking system.

[0011] The fixed pulse time driving module is used for outputting a time-adjustable pulse square wave signal.

[0012] The fault signal output module is used for detecting an external EHB power supply voltage and outputting an EHB fault signal to the whole vehicle.

[0013] The actuator output switching module is used for switching the power supply mode of the actuator motor from EHB power supply to backup power supply.

[0014] Optionally, the current detection module corresponds to a backup braking system power supply circuit, which specifically comprises a backup power supply signal, a backup power supply control signal, a power management chip U6, a power conversion chip U5, a third resistor R3, a fourth resistor R4, a fourteenth resistor R14, a thirteenth resistor R13, a first NMOS tube Q1 and a second NMOS tube Q2.

[0015] The backup power supply signal is connected to the anode of the backup power supply, and the backup power supply provides backup power for the entire circuit.

[0016] The backup power supply control signal is used to control the start and stop of the power supply through the key linkage of the KL15 key.

[0017] The power management chip U6 is connected with the first NMOS tube Q1 and the second NMOS tube Q2 respectively, and the power management chip U6 is used to control the power supply switching through the first NMOS tube Q1 and the second NMOS tube Q2.

[0018] The power management chip U6 is connected with the third resistor R3 and the fourth resistor R4, and the power management chip U6 is used to perform overcurrent protection by monitoring the third resistor R3 and the fourth resistor R4.

[0019] The power conversion chip U5 is used to convert the input voltage into the output voltage.

[0020] Optionally, the overcurrent protection specifically includes:

[0021] When the current flowing through the third resistor R3 and the fourth resistor R4 is greater than the overcurrent protection value, overcurrent protection is performed.

[0022] The calculation formula of the overcurrent protection value is specifically:

[0023]

[0024] Wherein, I(A) represents the overcurrent protection value, R3 represents the resistance value of the third resistor, R4 represents the resistance value of the fourth resistor, and A represents ampere.

[0025] Optionally, the fixed pulse time driving module corresponds to an EHB power failure detection and single fixed time driving circuit, which specifically comprises an EHB power failure detection sub-circuit, a 555 single pulse trigger sub-circuit and a MOS tube isolation driving sub-circuit.

[0026] The EHB power failure detection sub-circuit specifically comprises an eighteenth resistor R18, a voltage stabilizing diode D1 and a comparator U1.

[0027] The battery voltage VBAT obtains a reference voltage through the eighteenth resistor R18 and the voltage stabilizing diode D1.

[0028] The reference voltage is input to the inverse end of the comparator U1.

[0029] The EHB power supply positive network signal is input to the same phase end of the comparator U1.

[0030] The comparator U1 is used for detecting the change of the power supply voltage.

[0031] The 555 single pulse trigger sub-circuit specifically comprises a 555 timing chip U7.

[0032] The comparator U1 is connected with the TRIG pin of the 555 timing chip U7.

[0033] The 555 timing chip U7 is used for outputting a pulse signal of fixed time.

[0034] The MOS tube isolation driving sub-circuit comprises a voltage driving chip U8, a first MOS tube Q6 and a second MOS tube Q8.

[0035] The voltage driving chip U8 is connected with the first MOS tube Q6 and the second MOS tube Q8 respectively.

[0036] The pulse signal is input to the voltage driving chip U8 as a control signal.

[0037] The first MOS tube Q6 and the second MOS tube Q8 are used for controlling the output of the standby power supply, so as to ensure automatic switching to the standby power supply when the EHB power supply fails.

[0038] Optionally, the actuator output switching module corresponds to a driving execution motor circuit, which specifically comprises a first relay, a second relay, an execution motor, a first triode Q10 and a second triode Q11.

[0039] The input control signal is input to the base B of the first triode Q10 and the base B of the second triode Q11.

[0040] The first triode Q10 is connected with the first relay.

[0041] The second triode Q11 is connected with the second relay;

[0042] The first relay and the second relay are connected with the execution motor;

[0043] The first relay and the second relay are used for providing power to the execution motor through the power output, so as to ensure that the execution motor starts or stops working according to the control signal.

[0044] Optionally, the power supply fault output circuit corresponding to the fault signal output module comprises a comparator chip U4, an or gate chip U3A and a single-ended amplifier U1C.

[0045] The comparator chip U4 comprises a same-end comparator chip U4A and a reverse-end comparator chip U4B.

[0046] The EHB power positive signal is input into the same-end comparator chip U4A.

[0047] The standby output power signal is input into the reverse-end comparator chip U4B.

[0048] The or gate chip U3A is connected with the comparator chip U4, and the or gate chip U3A is used for outputting a fault signal FAULT.

[0049] The single-ended amplifier U1C is used for processing the fault signal FAULT, so as to ensure that the fault signal can be effectively output.

[0050] The technical scheme provided by the embodiment of the utility model has at least the following beneficial effects:

[0051] In the utility model, through the fixed pulse time driving module, the time-adjustable pulse square wave signal can be quickly generated, so that when the main braking system fails, the standby braking system can be quickly started and the required braking force can be provided, through the fault signal output module, the power supply voltage of the EHB system can be monitored in real time, so that the driver can obtain the warning in time and take necessary safety measures, the actuator output switching module can be smoothly switched to the standby power supply when the EHB power supply fails, so that even when the main power supply fails, the vehicle can still obtain sufficient braking capacity, through the current monitoring and overcurrent protection design of the current detection module, the problem of current overload can be solved, so that the circuit can be cut off in time under the overcurrent condition, further damage is avoided, through the integration of multiple key function modules, the complexity of the system is reduced, the stability and maintainability of the system are improved, and the probability of failure is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0053] Figure 1 A structural schematic diagram of a backup braking system provided by the embodiment of the present application is shown in the figure.

[0054] Figure 2 A power supply circuit diagram of the backup braking system provided by the embodiment of the present application is shown in the figure.

[0055] Figure 3 An EHB power failure detection and single fixed time driving circuit diagram provided by the embodiment of the present application is shown in the figure.

[0056] Figure 4 A driving execution motor circuit diagram provided by the embodiment of the present application is shown in the figure.

[0057] Figure 5 An EHB power failure output circuit diagram provided by the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0058] The technical solutions in the present application will be described below with reference to the drawings. It should be noted that, in order to make the embodiments more detailed, the following embodiments are the best, preferred embodiments, and other alternative ways can also be used by those skilled in the art to implement them; and the drawings are only used to more specifically describe the embodiments, and are not intended to specifically limit the present application.

[0059] It should be noted that in the specification, "one embodiment", "embodiment", "exemplary embodiment", "some embodiments" and the like indicate that the described embodiments can include specific features, structures or characteristics, but not necessarily every embodiment includes the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in combination with an embodiment, it should be within the knowledge of those skilled in the art to realize this feature, structure or characteristic in combination with other embodiments (whether or not explicitly described).

[0060] In general, terminology can be understood at least in part from the usage in context. For example, the term "one or more" as used herein, depending at least in part upon context, can be used to describe any feature, structure, or characteristic in a singular sense or can be used to describe combinations of features, structures or characteristics in a plural sense. Additionally, the term "based on" can be understood as not necessarily being confined to one set of factors or parameters, but can, instead, be broadly understood as being based on at least one factor or parameter, as appropriate.

[0061] It is to be understood that the terms "on", "over", and "above" in the present application should be interpreted in the broadest possible way so that "on" not only means "directly on" but also includes the meaning of being "on" with intervening features or layers therebetween, and "over" or "above" not only means "over" or "above" but also can include the meaning of being "over" or "above" without intervening features or layers therebetween.

[0062] In addition, spatially relative terms, such as "under", "below", "lower", "over", "upper" and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. The devices can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0063] With reference to the drawings, a schematic structural view of a backup braking system is shown. Figure 1 , a schematic structural view of a backup braking system provided by the present application is shown.

[0064] As Figure 1 Based on the original EHB function module and wire harness of the whole vehicle, the backup braking system is installed at the chassis of the whole vehicle or a position easy to install, the positive and negative wire harnesses connected with the original EHB output and execution motor of the whole vehicle are disconnected, and the wire harnesses are connected with signal 5, signal 6, signal 8 and signal 9 of the backup braking system respectively; the remaining signals can be installed on the original controller of the whole vehicle according to the signal description through the wire harness respectively.

[0065] As Figure 1As shown, the backup braking system includes a backup power supply and a current detection module (module 1), a fault signal output module (module 3), a fixed pulse time driving module (module 2), an actuator output switching module, and a motor drive (M), each module is connected through a signal line (signals 1 to 9), wherein signal 1 refers to the positive electrode of the backup power supply, corresponding to the "SBT_BA" T network signal in the circuit diagram. Signal 2 refers to the backup power supply control signal +, corresponding to the "STB_POWER_CTR" network signal in the circuit diagram. Signal 3 refers to the positive electrode of the EHB power supply, corresponding to the "EHB_POWER+" network signal in the circuit diagram, connected to the positive electrode of the trailer brake controller power supply, used for backup braking system start control. Signal 4 refers to the main circuit fault feedback (low effective), corresponding to the "FAULT" network signal in the circuit diagram. Signal 5 refers to the positive electrode of the actuator controller output, corresponding to the "EHB_OUT+" network signal in the circuit diagram, connected to the positive electrode of the motor output of the actuator (EHB) controller. Signal 6 refers to the negative electrode of the actuator controller output, corresponding to the "EHB_OUT-" network signal in the circuit diagram, connected to the negative electrode of the motor output of the actuator (EHB) controller. Signal 7 refers to the negative electrode of the system power supply, corresponding to the "GND" network signal in the circuit diagram. Signal 8 refers to the positive electrode of the execution motor, corresponding to the "MOTOR+" network signal in the circuit diagram. Signal 9 refers to the negative electrode of the execution motor, corresponding to the "MOTOR-" network signal in the circuit diagram.

[0066] The embodiment of the utility model provides a kind of backup braking system, comprising: current detection module, fixed pulse time driving module, fault signal output module, actuator output switching module and execution motor.

[0067] Current detection module and fault signal output module are connected.

[0068] Current detection module, fixed pulse time driving module, fault signal output module, actuator output switching module and motor are sequentially connected.

[0069] Current detection module is used for power supply and overcurrent protection of backup braking system.

[0070] Fixed pulse time driving module is used for output time adjustable pulse square wave signal.

[0071] Fault signal output module is used for detecting external EHB power voltage, and EHB fault signal is output to whole vehicle.

[0072] Actuator output switching module is used for switching the power supply mode of execution motor from EHB power supply to backup power supply.

[0073] It should be noted that the standby braking system can automatically switch to standby power supply when EHB power supply fails through the cooperative work of the current detection module, the fixed pulse time driving module, the fault signal output module and the actuator output switching module, ensures that the braking function is not affected, improves the reliability and safety of the system, and at the same time, accurate current monitoring and overcurrent protection can avoid circuit damage and ensure long-term stable operation of the system.

[0074] With reference to the accompanying drawings Figure 2 The accompanying drawings show the standby braking system power supply circuit diagram provided by the utility model.

[0075] As Figure 2 shown, Q1, Q2 (MOS tube): for switching power supply in different power supply, control current flows to standby power supply, R3, R4, R7, R8, R9, R10, R11, R14, R15, R21 (resistor) for limiting current, setting voltage division and adjusting the flow of current. C2, C6, C7, C8, C9, C10, C11 (capacitor) for filtering, stabilizing voltage and eliminating noise. U6 (power management chip) is a power management integrated circuit (IC), responsible for controlling power switching, monitoring current, processing input signals and controlling other components through its internal control logic. U5 (power conversion chip) is used to convert the input voltage into the required output voltage to ensure stable operation of the circuit. D2 (diode) is used to prevent reverse current flow and protect other parts of the circuit from damage.

[0076] In one possible implementation, the current detection module corresponds to the standby braking system power supply circuit, which specifically comprises: a standby power supply signal, a standby power supply control signal, a power management chip U6, a power conversion chip U5, a third resistor R3, a fourth resistor R4, a fourteenth resistor R14, a thirteenth resistor R13, a first NMOS tube Q1 and a second NMOS tube Q2.

[0077] The standby power supply signal accesses the positive pole of the standby power supply to provide standby power for the entire circuit.

[0078] The standby power supply control signal is used to control the start and stop of the power supply through the key linkage with KL15.

[0079] The power management chip U6 is connected with the first NMOS tube Q1 and the second NMOS tube Q2, and the power management chip U6 is used to switch the power supply by controlling the first NMOS tube Q1 and the second NMOS tube Q2.

[0080] The power management chip U6 is connected with the third resistor R3 and the fourth resistor R4, and the power management chip U6 is used for overcurrent protection by monitoring the third resistor R3 and the fourth resistor R4.

[0081] The power conversion chip U5 is used for converting the input voltage into the output voltage.

[0082] It should be noted that through the cooperation of the power management chip U6, the NMOS tubes Q1 and Q2, the start and stop of the standby power supply can be accurately controlled, and the overcurrent protection is performed through the resistors R3 and R4, thereby effectively ensuring that the circuit does not overload during the standby power supply switching process, at the same time, the power conversion chip U5 converts the input voltage into the required output voltage, thereby ensuring stable power supply of the system and improving the reliability and safety of the standby power supply.

[0083] In a possible implementation, the overcurrent protection specifically includes:

[0084] When the current flowing through the third resistor R3 and the fourth resistor R4 is greater than the overcurrent protection value, the overcurrent protection is performed.

[0085] The calculation formula of the overcurrent protection value specifically includes:

[0086]

[0087] Wherein, I(A) represents the overcurrent protection value, R3 represents the resistance value of the third resistor, R4 represents the resistance value of the fourth resistor, and A represents ampere.

[0088] In the utility model, STB_BAT network signal connects the anode of standby power supply. STB_POWER_CTR network signal is the power supply control port of system, and it can be connected with KL15 key of whole vehicle, when it is low level 0V state, this signal is given to the 7 feet of chip U6 (LT4356) after being divided by resistor R14, R15, and is less than the chip internal starting voltage threshold 2.1V, and the standby braking system is powered off and does not work, and the energy consumption is reduced. When it is high level 12V, the voltage of the 7 feet of chip U6 is greater than 2.1V at this time, and the chip 4 feet output high level makes the first NMOS tube Q1 and the second NMOS tube Q2 saturated conduction, and the standby braking system executes the power-on working state. This part of circuit module outputs 3 voltage for the power supply of system, and is BAT (voltage follows standby input voltage, and the typical value is 12V), VDD_5V, VCC_9V.

[0089] The calculation formula of the starting voltage threshold specifically includes:

[0090]

[0091] Wherein, V represents the starting voltage threshold, R14 represents the resistance value of the fourteenth resistor R14, and R15 represents the resistance value of the fifteenth resistor R15.

[0092] After power on, the chip U6 compares the voltage difference between the resistors R3 and R4 with the threshold value of the internal comparator, when the current flowing through R3 and R4 is too large, the voltage difference reaches 50mv, triggering the internal overcurrent alarm value of the chip, the 4th pin outputs low level, the first NMOS tube Q1 and the second NMOS tube Q2 are turned off, the output is disconnected, and the overcurrent protection function is achieved.

[0093] With reference to the accompanying drawings Figure 3 The utility model discloses EHB power failure detection and single fixed time drive circuit diagram provided by an embodiment of the utility model.

[0094] As Figure 3 shown, a backup power control circuit is displayed, mainly used for managing the start and stop of the backup power and signal output, ensuring that stable backup power can be provided when the main power fails, the circuit includes multiple elements and modules, and power switching and control are realized through coordinated work. U1A refers to a comparator U1, which is used for processing voltage signals, detecting EHB power voltage by being connected with a voltage source, and outputting a control signal. D1, D3 and D2 (diodes) are used for unidirectional current flow, protecting the circuit from reverse current. C3, C5, C13, C14 and C16 (capacitors) are used for filtering, stabilizing voltage and eliminating noise, ensuring smooth current flow of the circuit. R18, R19, R31, R32, R33, R35, R36, R37, R40, R41 and R42 (resistors) are used for current limiting, voltage division setting, feedback adjustment and control of the working state of the circuit. U7 (555 timing chip) is used for controlling the timing of the circuit, providing timing control signals (such as trigger signals). Q6, Q8 (MOS tubes) control the switching of the power supply, responsible for transmitting the backup power signal to the output end. U8 (voltage drive chip) is used for power isolation, protecting the system from power fluctuations. VDD provides the main power, BAT connects the backup power, STB POW OUT+ is used for outputting the backup power signal, and GND is the ground.

[0095] In a possible implementation, the EHB power failure detection and single fixed time drive circuit corresponding to the fixed pulse time drive module specifically includes an EHB power failure detection sub-circuit, a 555 single pulse trigger sub-circuit and a MOS tube isolation drive sub-circuit.

[0096] It should be noted that through the cooperative work of the EHB power failure detection sub-circuit, the 555 single pulse trigger sub-circuit and the MOS tube isolation drive sub-circuit, accurate power failure detection and control are realized. When the EHB power fails, the backup power system can be started in time, ensuring that the vehicle can still be switched to the backup power when the main power fails, and providing a safe and reliable braking function.

[0097] The EHB power supply off detection sub-circuit specifically comprises an eighteenth resistor R18, a stabilizing diode D1 and a comparator U1.

[0098] The battery voltage VBAT obtains a reference voltage through the eighteenth resistor R18 and the stabilizing diode D1.

[0099] The reference voltage is input to the inverting terminal of the comparator U1.

[0100] The EHB power supply positive network signal is input to the non-inverting terminal of the comparator U1.

[0101] The comparator U1 is used for detecting the change of the power supply voltage.

[0102] It should be noted that the stable reference voltage is formed by the battery voltage and the stabilizing diode, and compared with the EHB power supply positive signal, the comparator U1 can detect the change of the power supply voltage in real time, so as to ensure that when the EHB power supply voltage abnormally fluctuates or is off, the system can quickly respond and trigger the backup power supply switching, thereby improving the reliability and fault emergency ability of the system.

[0103] The 555 single pulse trigger sub-circuit specifically comprises a 555 timing chip U7.

[0104] The comparator U1 is connected with the TRIG pin of the 555 timing chip U7.

[0105] The 555 timing chip U7 is used for outputting a pulse signal with a fixed time.

[0106] It should be noted that the pulse signal with a fixed time is generated by the 555 timing chip U7, so that the system can respond to the EHB power supply off event in a precise time window, and the 555 timing chip provides reliable time control through the triggering action of the comparator U1, thereby avoiding the time sequence inaccuracy in the power supply switching process, and improving the stability and response speed of the backup braking system.

[0107] The MOS tube isolation driving sub-circuit comprises a voltage driving chip U8, a first MOS tube Q6 and a second MOS tube Q8.

[0108] The voltage driving chip U8 is connected with the first MOS tube Q6 and the second MOS tube Q8 respectively.

[0109] The pulse signal is input to the voltage driving chip U8 as a control signal.

[0110] The first MOS tube Q6 and the second MOS tube Q8 are used for controlling the output of the backup power supply, so as to ensure that the backup power supply is automatically switched when the EHB power supply is off.

[0111] It needs to be explained that through the cooperation of the voltage driving chip U8 and the first MOS tube Q6 and the second MOS tube Q8, the pulse signal can accurately control the switching of the standby power supply. When the EHB power supply is powered off, the MOS tube can quickly respond and automatically switch to the standby power supply for power supply, thereby guaranteeing the continuity and reliability of the system.

[0112] In the utility model, EHB power supply anode network EHB_POWER+ signal is input to the noninverting terminal of comparator U1, and the reference voltage of the inverting input terminal of the comparator is 5.1V, which is obtained through the current limiting resistor R18 and the voltage stabilizing diode D1 by VBAT, and when the EHB voltage is normal (usually 12V), the voltage of the noninverting terminal of U1 is greater than the reference voltage 5.1V of the inverting terminal, the comparator output high level is consistent with the default high level, at this time, the 3 pin output of U7 chip is low level 0V, and the rear standby drive does not work. The actuator relies on the EHB controller to brake normally. When the EHB power supply anode is powered off, the EHB_POWER+ signal becomes low level 0V, at this time, the voltage of the noninverting terminal of chip U1 is lower than the voltage 5.1V of the inverting terminal, the 3 pin output of chip U13 is high level 5V, this voltage drives the primary side LED of U8 chip to turn on, the 5 pin output of U8 chip is high level 9V, drives the rear MOS tube Q6, Q8 to turn on, so that the actuator rear network STB_POW_OUT+ is connected to the VBAT power supply, and the actuator is powered.

[0113] The calculation formula of the single pulse high level driving time of the 555 chip is specifically:

[0114] τ (s) = R32·C13

[0115] Wherein, τ (s) represents the single pulse high level driving time of the 555 chip, R32 represents the resistance value of the 23th resistor, and C13 represents the capacitance value of the 13th capacitor.

[0116] Reference Description Figure 4 The utility model discloses an actuator driving circuit, which belongs to the field of electrical engineering.

[0117] As Figure 4As shown, Relay1 and Relay2 (relays) are used to control the power switching of the actuator output, through the respective normally open contact (87a) and normally closed contact (30) to control the on and off of the power supply, the first relay and the second relay are connected with the battery (BAT) signal and the motor (M) output respectively. Q10 and Q11 (triode) are used to drive the relay coil, so that the relay can act according to the control signal, and the connection and disconnection of the control circuit. D4, D5, D6, D7 (diode) are used to protect the circuit and avoid damage caused by reverse current flow, especially when the relay is switched on, the diode plays a role in absorbing the reverse electromotive force generated by the inductive load. R43, R44, R45, R46 (resistor) is used to limit current and adjust the signal in the circuit to ensure the stable operation of the relay coil. C17 and C18 (capacitor) are used for filtering to ensure smooth current fluctuations in the circuit and avoid unnecessary interference. STB POWOUT+ and EHB OUT are power output ports that output standby power signals controlled by relays to provide power for the execution motor.

[0118] In one possible implementation, the actuator output switching module corresponds to a driving execution motor circuit, which specifically includes: a first relay, a second relay, an execution motor, a thirteenth triode Q10, and an eleventh triode Q11.

[0119] The input control signal is input to the base B of the thirteenth triode Q10 and the base B of the eleventh triode Q11.

[0120] The thirteenth triode Q10 is connected with the first relay.

[0121] The eleventh triode Q11 is connected with the second relay.

[0122] The first relay and the second relay are both connected with the execution motor.

[0123] The first relay and the second relay are used to provide power to the execution motor through the power output to ensure that the execution motor starts or stops working according to the control signal.

[0124] It should be noted that through the cooperation of the first relay, the second relay and the triode, the start and stop of the execution motor can be accurately controlled. The control signal drives the relay through the triode to ensure that the motor can quickly switch the power supply as needed, realize reliable motor driving and shutdown function, improve the response speed and stability of the system, and avoid damage to the circuit caused by overcurrent.

[0125] In the utility model, 555 chip 5 foot output OUT_CTRL signal high level 5V, synchronous to the base B of triode Q10 and Q11, base voltage is greater than triode source conduction voltage 0.7V, make Q10 and Q11 saturation conduction, the coil of relay Relay1 and Relay2 is electrified, its normally closed contact breaks, normally open contact closes, make the positive and negative port of execution motor access the output positive pole STB_POW_OUT+ and negative pole GND signal of standby braking system, let execution motor continue to rotate, realize emergency brake.If the above resistance R32 and C13 are R32=1MΩ, C13=4.7uF respectively, single pulse output time is 4.7s, then standby emergency brake time is also 4.7s.

[0126] Reference the accompanying drawings Figure 5 of the utility model embodiment provide EHB power supply fault output circuit diagram.

[0127] As Figure 5 shown, U4A and U4B (comparator chip) are used for monitoring power voltage and comparing, and voltage difference of EHB_POWER+ and STB_POW_OUT+ is detected respectively, and whether power failure occurs is determined by comparing the level state of these signals.R25, R26, R27, R28, R29, R30 (resistor) are used for adjusting voltage and current, and ensure the normal work of circuit and the stability of signal.U3A (or gate chip) is used for processing output signal from operational amplifier U4A and U4B, and comprehensively judges whether power is normal.When power failure occurs, the output signal of U3A will trigger fault signal.R23, R24, R25, R22 (resistor) are related to power, and ensure the proper adjustment of voltage and current, so that the circuit can operate normally.U1C (single-ended amplifier) is used for further processing power signal, and ensures accurate output of fault signal.Fault signal output (FAULT) is used for outputting fault alarm in the case of power abnormality.

[0128] In a possible implementation, the power supply fault output circuit corresponding to the fault signal output module specifically comprises: a comparator chip U4, an or gate chip U3A and a single-ended amplifier U1C.

[0129] The comparator chip U4 specifically comprises a same-end comparator chip U4A and a reverse-end comparator chip U4B.

[0130] The EHB power positive signal input same-end comparator chip U4A.

[0131] The standby output power signal input reverse-end comparator chip U4B.

[0132] The or gate chip U3A is connected with the comparator chip U4, and the or gate chip U3A is used for outputting fault signal FAULT.

[0133] The single-ended amplifier U1C is used for processing the fault signal FAULT, and ensures that the fault signal can be effectively output.

[0134] It should be noted that, through the cooperation of the comparator chip U4, the OR gate chip U3A and the single-ended amplifier U1C, the states of the EHB power supply and the backup power supply can be monitored in real time, and power supply faults can be detected in time. By comparing the power supply signals and generating the fault signal FAULT, it is effectively ensured that the fault alarm can be triggered quickly when the power supply is abnormal, reliable protection is provided for the system, and more serious faults or damage is avoided.

[0135] In the utility model, when EHB power supply loss, backup brake system intervention work, fault event also will synchronous feedback to the whole vehicle controller, make the whole vehicle can make reasonable action. EHB power supply positive pole EHB_POWER+ signal access U4 comparator chip's same end, backup output power supply STB_POW_OUT+ signal input U4's reverse end, its 2 group comparison voltage is 5.1V, when EHB power supply positive pole power failure and backup output power supply STB_POW_OUT+ has output voltage, U4 comparator's output 1 foot and 7 foot all output low level 0V, this 2 output signals give to U3 or gate chip, make U3's output 12 foot become low level 0V, FAULT output low level alarm signal. Normal HB power supply positive pole no power failure, fault FAULT signal is high level signal.

[0136] The technical scheme provided by the utility model embodiment has at least the following beneficial effects:

[0137] In the utility model, through the fixed pulse time driving module, the time-adjustable pulse square wave signal can be quickly generated, so that when the main brake system fails, the backup brake system can be quickly started and the required braking force can be provided, the power supply voltage of the EHB system can be monitored in real time through the fault signal output module, the driver can be warned in time and take necessary safety measures, the actuator output switching module can be smoothly switched to the backup power supply when the EHB power supply fails, so that even when the main power supply fails, the vehicle can still have sufficient braking ability, the current overload problem can be solved through the current monitoring and overcurrent protection design of the current detection module, so that the circuit can be cut off in time under the overcurrent condition, further damage is avoided, through the integration of multiple key function modules, the complexity of the system is reduced, the stability and maintainability of the system are improved, and the probability of fault occurrence is reduced.

[0138] The utility model covers any alternative, modification, equivalent method and scheme which are made on the essence and range of the utility model. In order to make the public have the thorough understanding of the utility model, the specific details are explained in detail in the preferred embodiment of the utility model, and the utility model can also be completely understood without the description of these details for the person skilled in the art. In addition, in order to avoid unnecessary confusion to the essence of the utility model, the well-known method, process, flow, element and circuit and the like are not explained in detail.

[0139] The above is only the preferred embodiment of the utility model, and it should be pointed out that, for ordinary skilled person in the art, under the premise of not departing from the principle of the utility model, a plurality of improvements and refinements can also be made, and these improvements and refinements should also be regarded as the protection range of the utility model.

Claims

1. A backup braking system characterized by, The application relates to a current detection module, a fixed pulse time driving module, a fault signal output module, an actuator output switching module and an execution motor. The current detection module and the fault signal output module are connected. The current detection module, the fixed pulse time driving module, the fault signal output module, the actuator output switching module and the execution motor are sequentially connected. The current detection module is used for power supply and overcurrent protection of a backup braking system. The fixed pulse time driving module is used for outputting a time-adjustable pulse square wave signal. The fault signal output module is used for detecting an external EHB power supply voltage and outputting an EHB fault signal to a whole vehicle. The actuator output switching module is used for switching the power supply mode of the execution motor from EHB power supply to backup power supply. The current detection module corresponds to a backup braking system power supply circuit which specifically comprises a backup power supply signal, a backup power supply control signal, a power management chip U6, a power conversion chip U5, a third resistor R3, a fourth resistor R4, a fourteenth resistor R14, a thirteenth resistor R13, a first NMOS tube Q1 and a second NMOS tube Q2.

2. The backup braking system of claim 1, wherein, The backup power supply signal is connected to the anode of the backup power supply and provides backup power for the whole circuit. The backup power supply control signal is used for controlling the start and stop of the power supply through the KL15 key linkage. The power management chip U6 is connected with the first NMOS tube Q1 and the second NMOS tube Q2 respectively, and the power management chip U6 is used for controlling the first NMOS tube Q1 and the second NMOS tube Q2 to switch the power supply. The power management chip U6 is connected with the third resistor R3 and the fourth resistor R4, and the power management chip U6 is used for monitoring the third resistor R3 and the fourth resistor R4 to perform overcurrent protection. The power conversion chip U5 is used for converting the input voltage into the output voltage. The overcurrent protection specifically comprises:

3. The backup brake system of claim 2, wherein, When the current flowing through the third resistor R3 and the fourth resistor R4 is greater than an overcurrent protection value, overcurrent protection is performed. The calculation formula of the overcurrent protection value is specifically as follows: Wherein, I (A) represents the overcurrent protection value, R3 represents the resistance value of the third resistor, R4 represents the resistance value of the fourth resistor, and A represents ampere. The fixed pulse time driving module corresponds to an EHB power failure detection and single fixed time driving circuit which specifically comprises an EHB power supply power failure detection subcircuit, a 555 single pulse trigger subcircuit and a MOS tube isolation driving subcircuit.

4. The backup braking system of claim 1, wherein, The EHB power supply power failure detection subcircuit specifically comprises an eighteenth resistor R18, a stabilizing diode D1 and a comparator U1. The battery voltage VBAT obtains a reference voltage through the eighteenth resistor R18 and the stabilizing diode D1. The reference voltage is input to the reverse end of the comparator U1. The EHB power supply anode network signal is input to the same-phase end of the comparator U1. The comparator U1 is used for detecting the change of the power supply voltage. The 555 single pulse trigger subcircuit specifically comprises a 555 timing chip U7. The comparator U1 is connected with the TRIG pin of the 555 timing chip U7. ​ The 555 timing chip U7 is used for outputting pulse signal of fixed time; The MOS isolation driving sub-circuit comprises a voltage driving chip U8, a first MOS Q6 and a second MOS Q8; The voltage driving chip U8 is connected with the first MOS Q6 and the second MOS Q8 respectively; The pulse signal is inputted into the voltage driving chip U8 as a control signal; The first MOS Q6 and the second MOS Q8 are used for controlling the output of the standby power supply, so as to ensure automatic switching to the standby power supply when the EHB power supply is powered off.

5. The backup braking system of claim 1, wherein, The driving execution motor circuit corresponding to the executor output switching module comprises a first relay, a second relay, an execution motor, a first triode Q10 and a second triode Q11; The input control signal is inputted into the base B of the first triode Q10 and the base B of the second triode Q11; The first triode Q10 is connected with the first relay; The second triode Q11 is connected with the second relay; The first relay and the second relay are both connected with the execution motor; The first relay and the second relay are used for providing power to the execution motor through power output, so as to ensure that the execution motor starts or stops working according to the control signal.

6. The backup brake system of claim 1, wherein, The power failure output circuit corresponding to the fault signal output module comprises a comparator chip U4, an or gate chip U3A and a single-ended amplifier U1C; The comparator chip U4 comprises a same-end comparator chip U4A and a reverse-end comparator chip U4B; The EHB power supply positive signal is inputted into the same-end comparator chip U4A; The standby output power supply signal is inputted into the reverse-end comparator chip U4B; The or gate chip U3A is connected with the comparator chip U4, and the or gate chip U3A is used for outputting a fault signal FAULT; The single-ended amplifier U1C is used for processing the fault signal FAULT, so as to ensure that the fault signal can be effectively outputted.

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