Parking braking control system

Abstract

The utility model discloses a parking brake control system which comprises a first micro-control unit, a first power management chip, a first data selector, a first pre-driver, a first H-bridge circuit, first calipers, a second micro-control unit, a second power management chip, a second data selector, a second pre-driver, a second H-bridge circuit and second calipers. The first micro-control unit, the first power management chip, the first data selector, the first pre-driver, the first H-bridge circuit and the first caliper form a first subsystem; the second micro-control unit, the second power management chip, the second data selector, the second pre-driver, the second H-bridge circuit and the second caliper form a second subsystem; the two systems keep enough independence, it is ensured that failure of one system does not affect operation of the other system, at least one caliper is reserved in the system design to achieve the braking function, guarantee is provided for the parking braking system from the hardware level, and safety is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle braking, in particular to a parking brake control system. Background Art

[0002] In the area of braking technology, GB 21670-2008 requires that parking brake systems equipped with electronic transmission devices be able to engage the parking brake from the driver's position and hold a fully loaded vehicle stationary on an 8% uphill or downhill slope if the internal wiring of the electronic transmission or the external wiring of the electronic control unit (excluding the power supply) is damaged, or if the control device fails. The industry currently addresses this requirement through redundancy, using two MCUs, PMICs, and driver chips to ensure that even if a single chip fails, the system can still "engage the parking brake from the driver's position and hold a fully loaded vehicle stationary on an 8% uphill or downhill slope."

[0003] Most current technical solutions for EPB redundancy solutions use logic to control the instructions given by the MCU to prevent conflicts on the execution end. However, the reliability of the operation and transmission of logical instructions is greatly reduced when the corresponding components fail, so the emergency response capability in emergency situations is not high.

[0004] Therefore, it is urgent to study a parking brake system that can guarantee the parking brake capability of the system at the hardware level and improve the ability to cope with sudden emergencies. Utility Model Content

[0005] This specification provides a parking brake control system to overcome at least one technical problem existing in the related art.

[0006] According to an embodiment of the present specification, a parking brake control system is provided, comprising a first microcontroller unit, a first power management chip, a first data selector, a first pre-driver, a first H-bridge circuit, a first caliper, a second microcontroller unit, a second power management chip, a second data selector, a second pre-driver, a second H-bridge circuit, and a second caliper, wherein:

[0007] The first micro control unit and the first power management chip constitute a first subsystem, and the second micro control unit and the second power management chip constitute a second subsystem; the first data selector includes a first address selection terminal, a first input terminal, a second input terminal, and a first output terminal; the second data selector includes a second address selection terminal, a third input terminal, a fourth input terminal, and a second output terminal;

[0008] The FS port of the first microcontroller unit and the ERROUT port of the first power management chip are connected to the first address selection terminal of the first data selector and the second address selection terminal of the second data selector through an AND gate logic circuit; the COMMAND instruction port of the first power management chip is connected to the first input terminal of the first data selector and the third input terminal of the second data selector; and the COMMAND instruction port of the second power management chip is connected to the second input terminal of the first data selector and the fourth input terminal of the second data selector;

[0009] The first output end of the first data selector is connected to the input end of the first pre-driver, the first pre-driver is connected to the first caliper via the first H-bridge circuit, and the first H-bridge circuit and the first micro control unit form a loop to control the first caliper;

[0010] The second output end of the second data selector is connected to the input end of the second pre-driver, the second pre-driver is connected to the second caliper through the second H-bridge circuit, and the second H-bridge circuit and the second micro control unit form a loop to control the second caliper.

[0011] Preferably, when any device in the first microcontroller unit or the first power management chip in the first subsystem fails, the system switches the address selection end of the data selector, and the second subsystem performs instruction calculation to drive the first caliper and the second caliper to operate.

[0012] Preferably, when any one of the first data selector or the second data selector fails, the system connects the signal output by the first microcontroller unit to the execution path through another data selector that is not faulty among the first data selector and the second data selector, thereby driving one of the first caliper and the second caliper to operate.

[0013] Preferably, when the first pre-driver or the second pre-driver fails, the system connects the signal output by the first microcontroller unit to the execution path through another pre-driver of the first pre-driver and the second pre-driver that is not faulty, thereby driving one of the first caliper and the second caliper to operate.

[0014] Preferably, when the first H-bridge circuit or the second H-bridge circuit fails, the system connects the signal output by the first microcontroller unit to the execution path through another H-bridge circuit in the first H-bridge circuit and the second H-bridge circuit that is not faulty, thereby driving one of the first caliper and the second caliper to operate.

[0015] The beneficial effects of the embodiments of this specification are as follows:

[0016] An embodiment of the present specification provides a parking brake control system, comprising a first microcontroller unit, a first power management chip, a first data selector, a first pre-driver, a first H-bridge circuit, a first caliper, a second microcontroller unit, a second power management chip, a second data selector, a second pre-driver, a second H-bridge circuit, and a second caliper. The first microcontroller unit and the first power management chip constitute a first subsystem, and the second microcontroller unit and the second power management chip constitute a second subsystem. The two systems are used for redundancy to ensure system safety. The first data selector and the second data selector respectively include an address selection terminal, two output terminals, and an output terminal, serving as hardware switching switches for the redundant system to ensure that when the first subsystem is normal, only instructions from the first subsystem are sent to the execution terminal. When the first subsystem fails, a hardware switch is performed so that instructions from the second subsystem are sent to the execution terminal. This embodiment not only ensures sufficient independence of the two systems, but also ensures that the failure of one system does not affect the other. This provides hardware protection for the parking brake system, greatly improving the ability to respond to dangerous emergencies and enhancing safety.

[0017] The innovative features of the embodiments of this specification include:

[0018] 1. In this manual, a conversion switch, i.e., a data selector, is added to the hardware architecture to ensure that when the first subsystem is normal, only the instructions of the first subsystem will be sent to the execution end. When the first subsystem fails, the hardware will switch so that the instructions of the second subsystem will be sent to the execution end. Through the hardware switching circuit, it can be ensured that under normal circumstances, the instructions of the second subsystem will not affect the normal operation of the system, and it can also ensure that after the first subsystem fails, the controller will be quickly handed over to the second subsystem for control.

[0019] 2. In this specification, the mechanism of automatic hardware switching after a single point failure in the entire hardware architecture can ensure the independence of the first subsystem and the second subsystem, and fully considers the independence of the entire system. The drive power supply of the two H-bridges is independent, and the power supply of all chips is independent. This ensures that after a single system fails, at least half of the calipers can still be retained to achieve the expected function. This is one of the innovative points of the embodiments of this specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of this specification or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is a structural diagram of a parking brake control system provided in one embodiment of this specification.

[0022] Among them, 1 represents a first micro control unit, 2 represents a first power management chip, 3 represents a first data selector, 4 represents a first pre-driver, 5 represents a first H-bridge circuit, 6 represents a first caliper, 7 represents a second micro control unit, 8 represents a second power management chip, 9 represents a second data selector, 10 represents a second pre-driver, 11 represents a second H-bridge circuit, 12 represents a second caliper, 13 represents a first input terminal, 14 represents a second input terminal, 15 represents a first output terminal, 16 represents a first address selection terminal, 17 represents a fourth input terminal, 18 represents a second output terminal, 19 represents a second address selection terminal, and 20 represents a third input terminal. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of this specification to clearly and completely describe the technical solutions in the embodiments of this specification. Obviously, the embodiments described are only part of the embodiments of this utility model, not all of the embodiments. Based on the embodiments of this utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this utility model.

[0024] It should be noted that the terms "including" and "having" and any variations thereof in the embodiments of this specification and the accompanying drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to the process, method, product, or apparatus.

[0025] The embodiments of this specification disclose a parking brake control system, which is described in detail below.

[0026] Figure 1 This is a schematic diagram of the structure of a parking brake control system provided in one embodiment of this specification. Figure 1As shown, a parking brake control system includes a first microcontroller unit 1, a first power management chip 2, a first data selector 3, a first pre-driver 4, a first H-bridge circuit 5, a first caliper 6, a second microcontroller unit 7, a second power management chip 8, a second data selector 9, a second pre-driver 10, a second H-bridge circuit 11 and a second caliper 12, wherein

[0027] The first microcontroller unit 1 and the first power management chip 2 form a first subsystem, while the second microcontroller unit 7 and the second power management chip 8 form a second subsystem. The first data selector 3 and the second data selector 9 each include an address selection terminal, two input terminals, and an output terminal. Specifically, the first data selector 3 includes a first address selection terminal 16, a first input terminal 13, a second input terminal 14, and a first output terminal 15. The second data selector 9 includes a second address selection terminal 19, a third input terminal 20, a fourth input terminal 17, and a second output terminal 18.

[0028] The FS port of the first microcontroller unit 1 and the ERROUT port of the first power management chip 2 are connected to the address selection end of the first data selector 3 and the address selection end of the second data selector 9 through an AND gate logic circuit. The COMMAND instruction port of the first power management chip 2 is connected to one input end of the first data selector 3 and one input end of the second data selector 9. The COMMAND instruction port of the second power management chip 8 is connected to another input end of the first data selector 3 and another input end of the second data selector 9.

[0029] The output end of the first data selector 3 is connected to the first pre-driver 4 , which is connected to the first caliper 6 via the first H-bridge circuit 5 . The first H-bridge circuit 5 and the first micro control unit 1 form a loop to control the first caliper 6 .

[0030] The output end of the second data selector 9 is connected to the second pre-driver 10 , which is connected to the second caliper 12 via a second H-bridge circuit 11 . The second H-bridge circuit 11 and the second micro control unit 7 form a loop to control the second caliper 12 .

[0031] In the specific implementation, the first microcontroller unit MCU1: Microcontroller 1; the first power management chip PMIC1: Power Management Integrated Circuit 1; the second microcontroller unit MCU2: Microcontroller 2; the second power management chip PMIC2: Power Management Integrated Circuit2; the embodiment of this specification has two independent control channels and two common execution channels, MCU1 and PMIC1 constitute control system 1, and MCU2 and PMIC2 constitute control system 2.

[0032] The EPB (electric park brake) requires functionality that meets ASIL-D functional safety standards, so the selected chips all meet ASIL-D functional safety standards. ASIL-D-compliant MCUs and PMICs typically have pin outputs to indicate whether the chip is faulty. This pin signal is used to control the chip's selection and enable automatic switching after a failure.

[0033] When there is no failure in any device in the system, system 1 uses switch input, sensor information and other inputs (not the focus of this article, so it is useless to reflect it in the Figure 1 ), analyzes and gives instructions to drive the two calipers to operate; when any device of MCU1 or PMIC1 in system 1 fails, the MUX chip will be switched, and MCU2 will perform calculations and give instructions to drive the two calipers to operate.

[0034] Specifically, when any device in the first microcontroller unit 1 or the first power management chip 2 in the first subsystem fails, the system switches the address selection end of the data selector, and the second subsystem performs instruction calculation to drive the two calipers to operate. When the first data selector 3 or the second data selector 9 fails, the system connects the signal output by the first microcontroller unit to the execution path through another data selector that has not failed, thereby driving one caliper to operate. When the first pre-driver 4 or the second pre-driver 10 fails, the system connects the signal output by the first microcontroller unit to the execution path through another pre-driver that has not failed, thereby driving one caliper to operate. When the first H-bridge circuit 5 or the first H-bridge circuit 11 fails, the system connects the signal output by the first microcontroller unit to the execution path through another H-bridge circuit that has not failed, thereby driving one caliper to operate.

[0035] Then, in a specific embodiment, when a single MUX chip fails, it can still be ensured that the instruction given by MCU1 is given to the execution channel of another MUX connected to this channel, driving a caliper to perform an action.

[0036] When a single pre-driver chip fails, it can still ensure that the instructions given by MCU1 are given to another pre-driver to perform a single caliper action.

[0037] When a single H-bridge driver fails, it can still ensure that the instructions given by MCU1 are given to the other H-bridge to perform a single caliper action.

[0038] Through the above analysis, it can be ensured that any single failure can ensure that at least one caliper can be driven normally.

[0039] In summary, the embodiments of this specification provide a parking brake control system. On the premise of setting up two independent systems as redundant protection, a data selector is designed as a hardware-level protection, which not only ensures sufficient independence of the two systems, but also ensures that the failure of one system does not affect the other. In addition, at least half of the calipers are retained in the system design to achieve the expected braking function, providing protection for the parking brake system from the hardware level, greatly improving the ability to respond to dangerous emergencies, and improving safety.

[0040] Those skilled in the art will appreciate that the accompanying drawings are merely schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily necessary for implementing the present invention.

[0041] Those skilled in the art will appreciate that the modules in the apparatuses of the embodiments may be distributed in the apparatuses of the embodiments as described in the embodiments, or may be located in one or more apparatuses different from the embodiments with corresponding changes. The modules in the above embodiments may be combined into one module or further divided into multiple sub-modules.

[0042] 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 it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. 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. A parking brake control system, characterized in that: The control system includes a first microcontroller unit, a first power management chip, a first data selector, a first pre-driver, a first H-bridge circuit, a first caliper, a second microcontroller unit, a second power management chip, a second data selector, a second pre-driver, a second H-bridge circuit and a second caliper, wherein: The first micro control unit and the first power management chip constitute a first subsystem, and the second micro control unit and the second power management chip constitute a second subsystem; the first data selector includes a first address selection terminal, a first input terminal, a second input terminal, and a first output terminal; the second data selector includes a second address selection terminal, a third input terminal, a fourth input terminal, and a second output terminal; The FS port of the first microcontroller unit and the ERROUT port of the first power management chip are connected to the first address selection terminal of the first data selector and the second address selection terminal of the second data selector through an AND gate logic circuit; the COMMAND instruction port of the first power management chip is connected to the first input terminal of the first data selector and the third input terminal of the second data selector; and the COMMAND instruction port of the second power management chip is connected to the second input terminal of the first data selector and the fourth input terminal of the second data selector; The first output end of the first data selector is connected to the input end of the first pre-driver, the first pre-driver is connected to the first caliper via the first H-bridge circuit, and the first H-bridge circuit and the first micro-control unit form a loop to control the first caliper; The second output end of the second data selector is connected to the input end of the second pre-driver, the second pre-driver is connected to the second caliper through the second H-bridge circuit, and the second H-bridge circuit and the second micro control unit form a loop to control the second caliper.

2. The system according to claim 1, wherein: When any device in the first microcontroller unit or the first power management chip in the first subsystem fails, the system switches the address selection end of the data selector, and the second subsystem performs instruction calculation to drive the first caliper and the second caliper to operate.

3. The system according to claim 1, wherein: When any one of the first data selector or the second data selector fails, the system connects the signal output by the first microcontroller unit to the execution path through the other data selector that is not faulty among the first data selector and the second data selector, thereby driving one of the first caliper and the second caliper to operate.

4. The system according to claim 1, wherein: When the first pre-driver or the second pre-driver fails, the system connects the signal output by the first microcontroller unit to the execution path through the other pre-driver of the first pre-driver and the second pre-driver that is not faulty, thereby driving one of the first caliper and the second caliper to operate.

5. The system according to claim 1, wherein: When the first H-bridge circuit or the second H-bridge circuit fails, the system connects the signal output by the first microcontroller unit to the execution path through the other H-bridge circuit that is not faulty in the first H-bridge circuit and the second H-bridge circuit, thereby driving one of the first caliper and the second caliper to operate.

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