A tractor redundant safety air brake system

Abstract

The present application provides a kind of tractor redundancy safety air pressure brake system, the proportional relay valve is used to when electronic brake system normal, according to the pressure correspondence of pre-stored control port and outlet, and the pressure value of actual control port, the pressure of output to ABS solenoid valve inlet is decided, so as to adjust the braking force of left and right sides, to adjust the situation of running deviation in vehicle braking process;When electronic brake system fails, the outlet of proportional relay valve is communicated with inlet, and the outlet air pressure of electronic brake system acts on ABS solenoid valve through proportional relay valve, realizes the braking of front axle, to ensure the remaining braking efficiency under the condition of electronic brake system failure, achieves redundancy brake effect, effectively improves the reliability of tractor safety brake system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automobile braking, in particular to a redundant safety pneumatic braking system of a tractor. BACKGROUND

[0002] Commercial vehicles, especially heavy-duty tractor trucks, play a vital role in modern logistics. Due to the large cargo mass and volume of the whole vehicle, higher requirements are put forward for the safety and stability of the tractor vehicle. In order to meet the transportation of bulk goods, safe and effective braking performance is particularly important, and the rapid response and precise execution of the braking system are the top priority.

[0003] In the prior art, the safety braking system of the tractor generally uses an EBS (Electronic Brake System) braking system for safety braking. However, the reliability of single braking is low, and in the case of normal EBS braking system, the vehicle cannot correct the deviation during braking. In the case of EBS braking system failure, the normal braking force and comfort in mechanical mode cannot guarantee the braking of the front axle in the case of front axle air supply pipe failure, making it difficult to ensure the remaining braking efficiency in the case of electronic braking system failure, and the reliability of the safety braking system of the tractor is low. SUMMARY

[0004] In order to solve the problems in the prior art, the present application innovatively proposes a redundant safety pneumatic braking system of a tractor, which effectively solves the problem of low reliability of the redundant safety pneumatic braking system of the tractor caused by the prior art, and effectively improves the reliability of the safety braking system of the tractor.

[0005] The first aspect of the present application provides a tractor redundant safety air pressure brake system, comprising: an air compressor, a brake signal transmitter, an air treatment unit, a proportional relay valve, an ABS solenoid valve, an air cylinder, a trailer control module, a trailer joint, an electronic parking module, an electronic brake system, the air outlet of the air compressor is connected with the air inlet of the air treatment unit; the air outlet of the air treatment unit is respectively connected with the air inlet of the air cylinder, the air inlet of the electronic parking module, the air inlet of the trailer control module and the air inlet of the proportional relay valve; the air outlet of the air cylinder is respectively connected with the air inlet of the electronic brake system and the air inlet of the brake signal transmitter; the air outlet of the brake signal transmitter is respectively connected with the control port of the electronic brake system, the control port of the proportional relay valve and the control port of the trailer control module, for realizing the control of the electronic brake system, the proportional relay valve and the trailer control module; the air outlet of the electronic parking module is connected with the control port of the trailer control module; the air outlet of the trailer control module is connected with the control port of the trailer joint, the proportional relay valve is used for determining the pressure output to the air inlet of the ABS solenoid valve according to the pressure corresponding relationship between the control port and the air outlet and the pressure value of the actual control port when the electronic brake system is normal, so as to adjust the braking force of the left and right sides to adjust the deviation in the vehicle braking process; when the electronic brake system fails, the air outlet of the proportional relay valve is communicated with the air inlet, and the air pressure of the air outlet of the electronic brake system acts on the ABS solenoid valve through the proportional relay valve to realize the braking of the front axle, so as to ensure the remaining braking efficiency under the failure of the electronic brake system and achieve the redundant braking effect.

[0006] Optionally, the electronic brake system comprises an EBS single-channel module and an EBS double-channel module, the air cylinder comprises a front axle air cylinder and a rear axle air cylinder, the air inlet of the EBS single-channel module is connected with the air outlet of the front axle air cylinder for controlling the pressure output of the whole front axle; the air inlet of the EBS double-channel module is connected with the air outlet of the rear axle air cylinder for controlling the pressure output of the brake chambers on the left and right sides of the rear axle; the control ports of the EBS single-channel module and the EBS double-channel module are respectively connected with the air outlet of the brake signal transmitter.

[0007] Further, the ABS solenoid valve comprises a front axle right ABS solenoid valve and a front axle left ABS solenoid valve, the air inlet of the front axle right ABS solenoid valve is connected with the air outlet of the proportional relay valve, the air inlet of the front axle left ABS solenoid valve is connected with the first air outlet of the EBS single-channel module, and the second air outlet of the EBS single-channel module is connected with the air inlet of the proportional relay valve;

[0008] The proportional relay valve is used to determine the pressure of the front axle right ABS solenoid valve outlet according to the pre-stored pressure corresponding relationship between the control port and the inlet port and the actual pressure value of the control port when the EBS single channel module and the EBS double channel module are normal, so as to adjust the braking forces of the left and right sides to adjust the left deviation during the vehicle braking process.

[0009] Optionally, the electronic braking system further comprises a central processing module, which acquires the electric signal and the air signal generated by the brake signal transmitter, the electric signal being used to acquire the pedal stroke information of the driver transmitted by the brake signal transmitter; according to the percentage of the pedal stroke information in the full stroke and the pre-set braking force distribution result of the brake, the pressure request values respectively distributed to the front axle, the rear axle and the trailer are determined and transmitted to the EBS single channel module, the EBS double channel module and the trailer control module respectively.

[0010] Further, the EBS single channel module, the EBS double channel module and the trailer control module are internally integrated with pressure sensors, which are used to determine whether the actual pressure output of the EBS single channel module, the EBS double channel module and the trailer control module is consistent with the expected value in real time, so as to realize the closed-loop control of the braking force.

[0011] Optionally, the inlet port of the electronic parking module is connected with the outlet port of the air treatment unit, and the outlet port of the electronic parking module is connected with the inlet port of the rear axle parking air chamber and the control port of the trailer control module respectively, which is used to realize the parking function through the rear axle parking air chamber and the trailer control module when the parking signal is acquired.

[0012] Optionally, the determination of the pressure output to the ABS solenoid valve inlet according to the pre-stored pressure corresponding relationship between the control port and the outlet port and the actual pressure value of the control port specifically comprises:

[0013] acquiring the pressure values of the proportional relay valve inlet and the control port, and determining the pressure corresponding relationship between the control port and the outlet port according to the acquired pressure value relationship of the proportional relay valve inlet and the control port;

[0014] determining the pressure output from the proportional relay valve outlet to the ABS solenoid valve inlet according to the actual pressure of the control port and the corresponding determined pressure corresponding relationship.

[0015] Further, the determination of the pressure corresponding relationship between the control port and the outlet port according to the acquired pressure value relationship of the proportional relay valve inlet and the control port specifically comprises:

[0016] Judge whether the pressure value relationship of the obtained inlet and control port of the proportional relay valve meets the first function relationship, if the first function relationship is met, the pressure corresponding relationship of the control port and the outlet port corresponds to the first pressure corresponding relationship;

[0017] If the first function relationship is not met, judge whether the pressure value of the inlet of the proportional relay valve is zero, if it is zero, the pressure corresponding relationship of the control port and the outlet port corresponds to the second pressure corresponding relationship, if it is not zero, the pressure corresponding relationship of the control port and the outlet port corresponds to the third pressure corresponding relationship, wherein the first pressure corresponding relationship, the second pressure corresponding relationship and the third pressure corresponding relationship are proportional relationships, and the slope of the first pressure corresponding relationship, the slope of the second pressure corresponding relationship and the slope of the third pressure corresponding relationship decrease in turn.

[0018] Further, the first function relationship is:

[0019] Wherein, P 12 The pressure value of the inlet of the proportional relay valve is P4, the pressure value of the control port of the proportional relay valve is P4.

[0020] Optionally, in the case of electronic brake system failure, the outlet of the proportional relay valve is communicated with the inlet, the outlet gas pressure of the electronic brake system acts on the ABS solenoid valve through the proportional relay valve, and the front axle is braked to ensure the remaining braking efficiency under the condition of electronic brake system failure, and the redundant braking effect is achieved, which is specifically:

[0021] When the electronic brake system fails or fails, the brake signal transmitter enters the standby pressure mode, the standby solenoid valve in the EBS single channel module and the EBS double channel module is always open, when the driver steps on the brake pedal, the outlet of the proportional relay valve is communicated with the inlet, the first outlet of the EBS single channel module is communicated with the second outlet, the outlet gas pressure of the electronic brake system reaches the left ABS solenoid valve of the front axle, the gas pressure of the outlet of the proportional relay valve and the gas pressure of the control port are in the first pressure corresponding relationship, and the front axle is braked to ensure the remaining braking efficiency under the condition of front axle energy supply pipeline failure, and the redundant braking effect is achieved.

[0022] The technical scheme adopted by the application includes the following technical effects:

[0023] 1. The proportional relay valve is used for determining the pressure output to the ABS solenoid valve inlet according to the pressure corresponding relationship between the control port and the outlet and the actual pressure value of the control port when the electronic brake system is normal, so as to adjust the braking force of the left and right sides to adjust the deviation during the braking process of the vehicle; when the electronic brake system fails, the outlet of the proportional relay valve is communicated with the inlet, and the outlet pressure of the electronic brake system acts on the ABS solenoid valve through the proportional relay valve to realize the braking of the front axle, so as to ensure the residual braking efficiency under the failure of the electronic brake system, achieve the redundant braking effect, effectively solve the problem of low reliability of the redundant safety pressure brake system of the tractor caused by the prior art, and effectively improve the reliability of the safety brake system of the tractor.

[0024] 2. In the technical scheme of the present application, a proportional relay valve with two inlets and one outlet is added to the EBS single-channel module in the electronic brake system, the inlet of the front axle right ABS solenoid valve is connected with the outlet of the proportional relay valve, the inlet of the front axle left ABS solenoid valve is connected with the first outlet of the EBS single-channel module, and the second outlet of the EBS single-channel module is connected with the inlet of the proportional relay valve; under the normal condition of the electronic brake system, the deviation during the braking process of the vehicle is corrected, the normal braking force and comfort in the mechanical mode are considered, and under the condition that the front axle supply pipe fails, the front axle brake can still participate in braking, the braking force of the whole vehicle in the failure mode is improved, so that the efficiency and safety of the braking system of the vehicle during transportation are more effectively ensured.

[0025] 3. In the technical scheme of the present application, the pressure sensors are integrated in the EBS single-channel module, the EBS double-channel module and the trailer control module, which are used for judging whether the actual pressure output of the EBS single-channel module, the EBS double-channel module and the trailer control module is consistent with the expected value in real time, so as to realize the closed-loop control of the braking force.

[0026] 4. In the technical scheme of the present application, the pressure values of the proportional relay valve inlet and the control port are obtained, the pressure corresponding relationship between the control port and the outlet is determined according to the obtained pressure value relationship of the proportional relay valve inlet and the control port, the pressure output from the outlet of the proportional relay valve to the inlet of the ABS solenoid valve is determined according to the actual pressure of the control port and the corresponding determined pressure corresponding relationship, and the effective braking of the front axle ABS solenoid valve by the proportional relay valve is realized.

[0027] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, for those skilled in the field, other drawings can also be obtained based on these drawings without any creative effort.

[0029] Figure 1 It is a structural schematic diagram of the system of the embodiment one in the present application scheme.

[0030] Figure 2 It is a structural schematic diagram of the air processing unit 15 in the system of the embodiment one in the present application scheme.

[0031] Figure 3 It is a structural schematic diagram of the air suspension system in the system of the embodiment one in the present application scheme.

[0032] Figure 4 It is a schematic diagram of the air pressure corresponding relationship between the air outlet and the control port of the proportional servo valve in the system of the embodiment one in the present application scheme.

[0033] Wherein: 1 - brake signal transmitter; 2 - pedal auxiliary air distribution; 3 - front axle right ABS solenoid valve; 4 - front axle left ABS solenoid valve; 5 - air compressor; 6 - energy supply heat dissipation steel pipe; 7 - proportional servo valve; 8 - EBS single channel module; 9 - trailer spiral pipe joint - red; 10 - trailer spiral pipe joint - yellow; 11 - auxiliary air distribution module; 12 - AMT air cylinder; 13 - trailer control module; 14 - energy supply hose; 15 - air processing unit; 16 - front axle air cylinder; 17 - EBS double channel module; 18 - electronic parking module; 19 - rear axle air cylinder; 20 - service brake air chamber; 21 - rear axle parking air chamber. DETAILED DESCRIPTION

[0034] In order to clearly illustrate the technical features of the present scheme, the present application will be described in detail below through specific embodiments and in combination with the drawings. The following disclosure provides many different embodiments or examples for implementing different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described below. In addition, the present application can repeatedly refer to numbers and / or letters in different examples. Such repetition is for the purpose of simplification and clarity, and in itself does not indicate the relationship between the various embodiments and / or settings being discussed. It should be noted that the components illustrated in the drawings are not necessarily drawn to scale. The present application omits the description of well-known components and processing techniques and processes to avoid unnecessary limitation of the present application.

[0035] Embodiment one

[0036] As Figures 1-4As shown, the present application provides a trailer redundant safety air pressure brake system, comprising: an air compressor 5, a brake signal transmitter 1, an air processing unit (APU) 15, a proportional relay valve 7, an ABS solenoid valve, an air cylinder, a trailer control module 13, a trailer joint, an electronic parking module (EPB module) 18, an electronic brake system, the air outlet of the air compressor 5 is connected with the air inlet of the air processing unit 15; the air outlet of the air processing unit 15 is respectively connected with the air inlet of the air cylinder, the air inlet of the electronic parking module 18, the air inlet of the trailer control module 13, and the air inlet of the proportional relay valve 7; the air outlet of the air cylinder is respectively connected with the air inlet of the electronic brake system and the air inlet of the brake signal transmitter 1; the air outlet of the brake signal transmitter 1 is respectively connected with the control port of the electronic brake system, the control port of the proportional relay valve 7, and the control port of the trailer control module 13, for realizing the control of the electronic brake system, the proportional relay valve 7, and the trailer control module 13; the air outlet of the electronic parking module 18 is connected with the control port of the trailer control module 13; the air outlet of the trailer control module 13 is connected with the control port of the trailer joint; the proportional relay valve 7 is used for determining the pressure output to the air inlet of the ABS solenoid valve according to the pre-stored pressure corresponding relationship between the control port and the air outlet and the actual pressure value of the control port, so as to adjust the braking force of the left and right sides, thereby adjusting the deviation in the vehicle braking process; in the case of electronic brake system failure, the air outlet of the proportional relay valve 7 is communicated with the air inlet, and the air pressure of the air outlet of the electronic brake system acts on the ABS solenoid valve through the proportional relay valve 7, so as to realize the braking of the front axle, thereby ensuring the remaining braking efficiency in the case of electronic brake system failure and achieving the redundant braking effect.

[0037] The electronic brake system comprises an EBS single-channel module 8 and an EBS double-channel module 17, the air cylinder comprises a front axle air cylinder 16 and a rear axle air cylinder 19, the air inlet of the EBS single-channel module 8 is connected with the air outlet of the front axle air cylinder 16, for controlling the pressure output of the whole front axle; the air inlet of the EBS double-channel module 17 is connected with the air outlet of the rear axle air cylinder 19, for controlling the pressure output of the left and right brake chambers of the rear axle; the control ports of the EBS single-channel module 8 and the EBS double-channel module 17 are respectively connected with the air outlet of the brake signal transmitter 1. Preferably, the air cylinder further comprises an AMT (automatically mechanically controlled transmission) air cylinder 12, and the air inlet of the AMT air cylinder 12 is connected with the air outlet of the air processing unit 15.

[0038] The ABS solenoid valve comprises a front axle right ABS solenoid valve 3 and a front axle left ABS solenoid valve 4, the air inlet of the front axle right ABS solenoid valve 3 is connected with the air outlet of the proportional relay valve 7, the air inlet of the front axle left ABS solenoid valve 4 is connected with the first air outlet of the EBS single-channel module 8, and the second air outlet of the EBS single-channel module 8 is connected with the air inlet of the proportional relay valve 7.

[0039] The proportional relay valve 7 is used to determine the pressure of the front axle right ABS solenoid valve 3 outlet according to the pre-stored control port and outlet pressure corresponding relationship and the actual control port pressure value, so as to adjust the braking force of the left and right sides, and to adjust the left running deviation in the vehicle braking process.

[0040] The air compressor 5 provides air source for the whole braking system. In order to ensure the output of sufficient high pressure gas, the high pressure gas is connected with the air inlet 11 of the APU air treatment unit 15 through the outlet of the air compressor 5, the energy supply heat dissipation steel pipe 6 and the energy supply hose 14. The outlets 21 and 22 of the air treatment unit 15 are connected with the front axle air reservoir 16 and the rear axle air reservoir 19 through nylon pipes respectively. The front axle air reservoir 16 supplies air to the 11 air inlet of the front axle EBS single channel module 8 and the brake signal transmitter 1 respectively. The rear axle air reservoir 19 supplies air to the 11 air inlet of the rear axle EBS double channel module 17 and the brake signal transmitter 1 respectively. The outlets 21 and 22 of the brake signal transmitter 1 control the EBS single channel module 8 (front axle) and the EBS double channel module 17 (rear axle) respectively. The pipe line of the 22 air inlet of the brake signal transmitter 1 is connected with the control port 4 of the proportional relay valve 7 through a three-way joint. The pipe line of the 21 air inlet of the brake signal transmitter 1 is connected with the control port 4 of the trailer control module 13 through a three-way joint. The 23.1 air outlet of the air treatment unit 15 is connected with the air inlet of the electronic parking module 18. The 21 air outlet of the electronic parking module 18 is connected with the rear axle parking air chamber 21. The 22 air outlet of the electronic parking module 18 is connected with the control port 43 of the trailer control module 13. The control of the electronic parking module 18 is controlled by the EPB switch in the cab. The 23 air inlet of the air treatment unit 15 is connected with the air inlet of the trailer control module 13. The 21 and 22 air outlets of the trailer control module 13 are connected with the trailer joint on the gantry through red and yellow spiral pipes respectively, that is, the trailer joint is divided into trailer spiral pipe joint-red 9 and trailer spiral pipe joint-yellow 10. The 24 air inlet of the air treatment unit 15 is connected with the air inlet 1 of the proportional relay valve 7 and the auxiliary air distribution module 11. The 21 air outlet of the auxiliary air distribution module 11 is connected with the air inlet 1 of the pedal auxiliary air distribution 2. The 24.1 air outlet of the air treatment unit 15 is connected with the AMT air reservoir. The 25 air inlet of the air treatment unit 15 is connected with the 1 air inlet of the air suspension ECAS (electronic controlled air suspension system) solenoid valve. The 27 air inlet of the air treatment unit 15 is connected with the ESS air inlet of the air compressor 5. That is, the air treatment unit 15 has one air inlet 11 and seven air outlets, which can meet various air pressure output and auxiliary air use conditions.

[0041] In this embodiment, the electronic parking module (i.e. electronic parking system, EPB) is used to replace the mechanical parking brake system; the front and rear axles are controlled by the EBS single and double channel modules respectively, which improves the response time of the braking system and the stability of the service brake. Specifically, the air outlet 22 of the front axle EBS single channel module 8 is connected to the air inlet 12 of the proportional relay valve 7, the air source of the air inlet 1 of the proportional relay valve 7 comes from the air outlet 24 of the air treatment unit 15, and the control port of the proportional relay valve 7 is simultaneously controlled by the control port of the EBS double channel module 17 and the air outlet 22 of the brake signal transmitter 1.

[0042] Under normal circumstances of the electronic brake system, the proportional relay valve 7 can adjust the air pressure of the front axle right side pipeline, i.e. adjust the air pressure output to the air inlet of the front axle right ABS solenoid valve 3, to correct the left deviation trend during vehicle braking; in the case of electronic brake system failure, the brake signal transmitter 1, the EBS single channel module 8 and the EBS double channel module 17 enter the standby pressure mode, which improves the braking force of the whole vehicle and ensures the safety of the vehicle during driving; in the case of failure of the front axle EBS single channel module 8 air supply pipeline, the proportional relay valve 7 connected with the front axle EBS single channel module 8 can also become the air inlet of the EBS single channel module 8, and the left side 21 of the EBS single channel module 8 is opened at the same time, so that the front axle brake can still provide braking force and improve the residual braking efficiency of the vehicle in the case of failure of the energy supply pipeline.

[0043] Preferably, the electronic brake system further comprises a central processing module (not shown in the figure), which obtains the electrical signal and air signal generated by the brake signal transmitter, the electrical signal is used to obtain the pedal stroke information transmitted by the brake signal transmitter; according to the percentage of the pedal stroke information in the full stroke and the pre-set brake force distribution result of the brake, the pressure request values respectively distributed to the front axle, the rear axle and the trailer are determined and transmitted to the EBS single channel module 8, the EBS double channel module 17 and the trailer control module 13 respectively. Specifically, when the driver steps on the pedal, the brake signal transmitter 1 with an integrated stroke sensor generates corresponding electrical signal and air signal, and the electrical signal feeds back the pedal stroke information to the central processing module inside the electronic brake system. The central processing module judges the deceleration demand of the driver according to the percentage of the brake signal transmitter's stepping stroke in the full stroke and the feeling curve, and gives the pressure request values of the front axle, the rear axle and the trailer according to the pre-set brake force distribution, while taking into account the uniform wear of the front and rear axle brakes. Then the values are transmitted to the EBS single channel module 8, the EBS double channel module 17 and the trailer control module 13 through the CAN line. The EBS single channel module 8 controls the pressure output of the whole front axle, the EBS double channel module 17 can control the pressure output of the left and right brake chambers of the rear axle respectively, and the trailer control module 13 controls the pressure output of the trailer control part.

[0044] Preferably, the EBS single-channel module 8, the EBS double-channel module 17 and the trailer control module 13 are each internally integrated with a pressure sensor for real-time determination of whether the actual pressure output of the EBS single-channel module 8, the EBS double-channel module 17 and the trailer control module 13 is consistent with the expected value, so as to realize closed-loop control of the braking force. That is, the EBS single-channel module 8, the EBS double-channel module 17 and the trailer control module 13 are each internally integrated with a pressure sensor arranged at the outlet side, for real-time acquisition of the outlet air pressure value of the EBS single-channel module 8, the EBS double-channel module 17 and the trailer control module 13, real-time determination of whether the actual pressure output is consistent with the expected value set in advance, and realization of closed-loop control of the braking force.

[0045] The air inlet of the electronic parking module 18 is in air connection with the air outlet of the air handling unit, and the air outlet of the electronic parking module 18 is connected with the air inlet of the rear axle parking air chamber 21 and the control port of the trailer control module 13, respectively, for realizing the parking function through the rear axle parking air chamber 21 and the trailer control module 13 when the parking signal is acquired. Specifically, when the EPB switch is pulled up, the electric signal will directly act on the electronic parking module 18 to realize the parking function; when the vehicle starts, the ECU (Electronic Control Unit) in the electronic parking module 18 will collect the vehicle clutch, gear and throttle (only the gear when AMT) signals to automatically release the parking without manual operation. When the vehicle is powered off, even if the handbrake is forgotten, the parking can also be automatically completed.

[0046] Further, the pressure output to the air inlet of the ABS solenoid valve is determined according to the pre-stored pressure corresponding relationship between the control port and the air outlet and the actual pressure value of the control port, and specifically includes:

[0047] The pressure values of the air inlet and the control port of the proportional relay valve are acquired, and the pressure corresponding relationship between the control port and the air outlet is determined according to the acquired pressure value relationship between the air inlet and the control port of the proportional relay valve;

[0048] The pressure output to the air inlet of the ABS solenoid valve from the air outlet of the proportional relay valve is determined according to the actual pressure of the control port and the corresponding determined pressure corresponding relationship.

[0049] Specifically, the pressure corresponding relationship between the control port and the air outlet is determined according to the acquired pressure value relationship between the air inlet and the control port of the proportional relay valve, and specifically includes:

[0050] It is determined whether the acquired pressure value relationship between the air inlet and the control port of the proportional relay valve satisfies a first functional relationship, and if the first functional relationship is satisfied, the pressure corresponding relationship between the control port and the air outlet corresponds to a first pressure corresponding relationship (such as the middle curve ① in FIG. 1). Figure 4 ​

[0051] If the first function relationship is not satisfied, it is judged whether the pressure value of the intake port of the proportional relay valve is zero. If it is zero, the pressure corresponding relationship between the control port and the gas outlet is the second pressure corresponding relationship (as shown in curve ② in the figure); if it is not zero, the pressure corresponding relationship between the control port and the gas outlet is the third pressure corresponding relationship (as shown in curve ③ in the figure); wherein the first pressure corresponding relationship, the second pressure corresponding relationship and the third pressure corresponding relationship are proportional relationships, and the slope of the first pressure corresponding relationship, the slope of the second pressure corresponding relationship and the slope of the third pressure corresponding relationship decrease in turn. Figure 4 Figure 4

[0052] Specifically, the first function relationship can be:

[0053] Wherein, P 12 is the pressure value of the intake port of the proportional relay valve, and P4 is the pressure value of the control port of the proportional relay valve.

[0054] When the electronic control system circuit is normal and fault-free, the brake signal transmitter 1 outputs an electrical signal at the same time as the output port 21, 22 of the brake signal transmitter 1 also outputs gas pressure. Under normal operation of the electronic control system, the two gas pressure signals will be blocked in the control port 4 of the corresponding module by the standby pressure solenoid in the EBS single-channel module 8 and the EBS double-channel module 17, and the output of gas pressure in the EBS single-channel module 8 and the EBS double-channel module 17 is completely controlled by the circuit. The gas pressure output at the 21 and 22 ports of the EBS single-channel module 8 is consistent, which together with the ABS solenoid valves on the right and left sides of the front axle (the front axle right ABS solenoid valve 3 and the front axle left ABS solenoid valve 4) determines the pressure of the brake air chamber on the right and left sides of the front axle. Since a proportional relay valve is added in the right output pipeline, the valve determines the pressure of the intake port 1 of the front axle right ABS solenoid valve 3 according to the pressure relationship curve of the 4 port and the 12 port, thereby optimizing the braking force on the right and left sides of the front axle and appropriately increasing the braking force on the right side to adjust the left deviation during vehicle braking.

[0055] When the electronic brake system fails, the gas outlet of the proportional relay valve is communicated with the intake port, and the gas pressure of the electronic brake system acts on the ABS solenoid valve through the proportional relay valve to realize the braking of the front axle, so as to ensure the residual braking efficiency under the failure of the electronic brake system and achieve the effect of redundant braking. Specifically:

[0056] ​​When the electronic brake system fails, the brake signal transmitter enters the standby mode, the standby solenoid valve in the EBS single-channel module and the EBS double-channel module is normally open, when the driver steps on the brake pedal, the outlet of the proportional relay valve is communicated with the inlet, the first outlet of the EBS single-channel module is communicated with the second outlet, the outlet gas pressure of the electronic brake system reaches the front axle left ABS solenoid valve, the gas pressure of the outlet of the proportional relay valve and the control port are in a first pressure corresponding relationship, the front axle is braked to ensure the remaining braking efficiency under the failure of the front axle energy supply pipeline and achieve the redundant braking effect.

[0057] Specifically, when the EBS electronic control system fails, the brake signal transmitter 1, the EBS single-channel module 8 and the EBS double-channel module 17 enter the standby mode, the standby solenoid valve in the EBS single-channel module 8 and the EBS double-channel module 17 is normally open, and enters the traditional air pressure control mode. However, the output pressure ratio of the 21 port and the 22 port of the brake signal transmitter 1 in the standby mode is 1:1.5, and without the proportional relay valve 7, the front axle brake is less involved, but when the driver steps on the brake pedal, the 4 port of the proportional relay valve 7 is controlled by the rear axle control pipeline, the 2 port of the proportional relay valve 7 is communicated with the 12 port, and since the 21 port and the 22 port of the EBS single-channel module 8 are communicated, the air pressure can also reach the front axle left ABS solenoid valve 4, when the proportional relay valve 7 is under the control of the larger pressure (i.e. the driver steps deeper, the vehicle demand braking force is larger), the output of the outlet 2 port and the control port 4 port is in a 1:1 relationship, when the vehicle demand braking force is smaller, the 2 port output air pressure is smaller, so as to ensure the comfort of the braking process. That is, the braking force under the failure of the electronic control module can be improved, and the comfort of the vehicle braking is also considered.

[0058] When the air supply pipeline of the front axle EBS single-channel module 8 fails, without the proportional relay valve 7, the front axle cannot participate in braking. Since the 1 port of the proportional relay valve 7 is supplied with air by the outlet 24 port of the air treatment unit 15, and the control loop is controlled by the control loop of the rear axle EBS double-channel module 17, under the condition that the air supply pipeline of the front axle EBS single-channel module 8 fails, the 2 port and the 12 port of the proportional relay valve 7 are communicated, and the 21 port and the 22 port of the EBS single-channel module 8 are communicated, the air pressure can also reach the front axle left ABS solenoid valve 4, the front axle is braked to ensure the remaining braking efficiency under the failure of the front axle energy supply pipeline. Achieve the redundant braking effect and ensure the safety of automobile driving.

[0059] The proportional relay valve is used for determining the pressure output to the intake port of the ABS solenoid valve according to the pressure corresponding relationship between the control port and the outlet port and the pressure value of the actual control port when the electronic brake system is normal, so as to adjust the braking forces on the left and right sides to adjust the deviation during the braking of the vehicle; when the electronic brake system fails, the outlet port of the proportional relay valve is communicated with the intake port, and the outlet pressure of the electronic brake system acts on the ABS solenoid valve through the proportional relay valve to realize the braking of the front axle, so as to ensure the residual braking efficiency under the failure of the electronic brake system, achieve the redundant braking effect, effectively solve the problem of low reliability of the redundant safety pressure brake system of the tractor caused by the prior art, and effectively improve the reliability of the safety brake system of the tractor.

[0060] In the technical scheme of the present application, a proportional relay valve with two-in-one-out control is added in the EBS single-channel module of the electronic brake system, the intake port of the front axle right ABS solenoid valve is connected with the outlet port of the proportional relay valve, the intake port of the front axle left ABS solenoid valve is connected with the first outlet port of the EBS single-channel module, and the second outlet port of the EBS single-channel module is connected with the intake port of the proportional relay valve; under the normal condition of the electronic brake system, the deviation during the braking of the vehicle is corrected, the normal braking force and comfort in the mechanical mode are considered, and under the condition that the front axle supply pipe fails, the front axle brake can still participate in braking, the braking force of the whole vehicle in the failure mode is improved, so that the efficiency and safety of the braking system of the vehicle during transportation are more effectively ensured.

[0061] In the technical scheme of the present application, the pressure sensors are integrated in the EBS single-channel module, the EBS double-channel module and the trailer control module, which are used for judging whether the actual pressure output of the EBS single-channel module, the EBS double-channel module and the trailer control module is consistent with the expected value in real time, and realizing the closed-loop control of the braking force.

[0062] In the technical scheme of the present application, the pressure values of the intake port and the control port of the proportional relay valve are obtained, the pressure corresponding relationship between the control port and the outlet port is determined according to the obtained pressure value relationship of the intake port and the control port of the proportional relay valve, the pressure output from the outlet port of the proportional relay valve to the intake port of the ABS solenoid valve is determined according to the pressure of the actual control port and the corresponding determined pressure corresponding relationship, and the effective braking of the front axle by the proportional relay valve to the front axle ABS solenoid valve is ensured.

[0063] The above describes the specific embodiments of the present application in combination with the drawings, but is not a limitation on the protection scope of the present application, and those skilled in the art should understand that various modifications or changes made by those skilled in the art on the basis of the technical scheme of the present application without creative labor are still within the protection scope of the present application.

Claims

1. A tractor redundant air brake system, comprising: The air compressor, brake signal transmitter, air processing unit, proportional relay valve, ABS solenoid valve, air cylinder, trailer control module, trailer connector, electronic parking module, electronic brake system, the air outlet of the air compressor is connected with the air inlet of the air processing unit; the air outlet of the air processing unit is connected with the air inlets of the air cylinder, the electronic parking module, the trailer control module and the proportional relay valve respectively; the air outlet of the air cylinder is connected with the air inlets of the electronic brake system and the brake signal transmitter respectively; the air outlet of the brake signal transmitter is connected with the control ports of the electronic brake system, the proportional relay valve and the trailer control module respectively, so as to realize the control of the electronic brake system, the proportional relay valve and the trailer control module; the air outlet of the electronic parking module is connected with the control port of the trailer control module; the air outlet of the trailer control module is connected with the control port of the trailer connector; the proportional relay valve is used for determining the pressure output to the air inlet of the ABS solenoid valve according to the pressure corresponding relationship between the control port and the air outlet and the pressure value of the actual control port when the electronic brake system is normal, so as to adjust the braking forces on the left and right sides and adjust the deviation of the vehicle in the braking process; when the electronic brake system is faulty, the air outlet of the proportional relay valve is communicated with the air inlet, and the air pressure of the electronic brake system is applied to the ABS solenoid valve through the proportional relay valve, so as to realize the braking of the front axle and ensure the remaining braking efficiency and achieve the redundant braking effect when the electronic brake system is faulty. The electronic brake system comprises an EBS single-channel module and an EBS double-channel module, the air cylinder comprises a front axle air cylinder and a rear axle air cylinder, the air inlet of the EBS single-channel module is connected with the air outlet of the front axle air cylinder, and the air inlet of the EBS double-channel module is connected with the air outlet of the rear axle air cylinder; the control ports of the EBS single-channel module and the EBS double-channel module are connected with the air outlet of the brake signal transmitter respectively. The ABS solenoid valve comprises a front axle right ABS solenoid valve and a front axle left ABS solenoid valve, the air inlet of the front axle right ABS solenoid valve is connected with the air outlet of the proportional relay valve, the air inlet of the front axle left ABS solenoid valve is connected with the first air outlet of the EBS single-channel module, and the second air outlet of the EBS single-channel module is connected with the air inlet of the proportional relay valve. The proportional relay valve is used for determining the pressure of the air outlet of the front axle right ABS solenoid valve according to the pressure corresponding relationship between the control port and the air outlet and the pressure value of the actual control port when the EBS single-channel module and the EBS double-channel module are normal, so as to adjust the braking forces on the left and right sides and adjust the deviation of the vehicle to the left in the braking process.

2. A tractor redundant air brake system according to claim 1 wherein, The electronic brake system further comprises a central processing module, which acquires an electric signal and an air signal generated by a brake signal transmitter, the electric signal being used to acquire pedal stroke information of a driver transmitted by the brake signal transmitter; According to the percentage of the pedal stroke information in the full stroke, and the pre-set brake force distribution result of the brake, pressure request values respectively allocated to the front axle, the rear axle and the trailer are determined and transmitted to the EBS single-channel module, the EBS double-channel module and the trailer control module respectively.

3. A tractor redundant air brake system according to claim 2, wherein, The EBS single-channel module, the EBS double-channel module and the trailer control module are internally integrated with pressure sensors, which are used to determine whether the actual pressure output of the EBS single-channel module, the EBS double-channel module and the trailer control module is consistent with the expected value in real time, so as to realize closed-loop control of the brake force.

4. A tractor redundant air brake system according to claim 1 wherein, The air inlet of the electronic parking module is connected with the air outlet of the air processing unit, and the air outlet of the electronic parking module is connected with the air inlet of the rear axle parking air chamber and the control port of the trailer control module respectively, so as to realize the parking function through the rear axle parking air chamber and the trailer control module when the parking signal is acquired.

5. A tractor redundant air brake system according to claim 1 wherein, The pressure output to the air inlet of the ABS solenoid valve according to the pre-stored pressure corresponding relationship between the control port and the air outlet, and the pressure value of the actual control port specifically comprises: The pressure values of the air inlet and the control port of the proportional relay valve are acquired, and the pressure corresponding relationship between the control port and the air outlet is determined according to the acquired pressure value relationship between the air inlet and the control port of the proportional relay valve; The pressure output to the air inlet of the ABS solenoid valve by the air outlet of the proportional relay valve is determined according to the pressure of the actual control port and the corresponding determined pressure corresponding relationship.

6. A tractor redundant air brake system according to claim 5 wherein, The pressure corresponding relationship between the control port and the air outlet determined according to the acquired pressure value relationship between the air inlet and the control port of the proportional relay valve specifically comprises: It is determined whether the acquired pressure value relationship between the air inlet and the control port of the proportional relay valve satisfies a first function relationship, if the first function relationship is satisfied, the pressure corresponding relationship between the control port and the air outlet corresponds to a first pressure corresponding relationship; If the first function relationship is not satisfied, it is determined whether the pressure value of the air inlet of the proportional relay valve is zero, if it is zero, the pressure corresponding relationship between the control port and the air outlet corresponds to a second pressure corresponding relationship; if it is not zero, the pressure corresponding relationship between the control port and the air outlet corresponds to a third pressure corresponding relationship; wherein the first pressure corresponding relationship, the second pressure corresponding relationship and the third pressure corresponding relationship are all proportional relationships, and the slope of the first pressure corresponding relationship, the slope of the second pressure corresponding relationship and the slope of the third pressure corresponding relationship decrease in turn.

7. A tractor redundant air brake system according to claim 6 wherein, The first function relationship is: P 12 ≥ wherein P 12 is the pressure value at the inlet of the proportional relay valve and P4 is the pressure value at the control port of the proportional relay valve.

8. A tractor redundant air brake system according to claim 6 wherein When the electronic brake system fails, the air outlet of the proportional relay valve is communicated with the air inlet, and the air pressure of the air outlet of the electronic brake system acts on the ABS solenoid valve through the proportional relay valve to realize the braking of the front axle, so as to ensure the remaining braking efficiency under the failure of the electronic brake system and achieve the redundant braking effect, which specifically comprises: When the electronic brake system fails, the brake signal transmitter enters the standby mode, the standby solenoid valve in the EBS single-channel module and the EBS double-channel module is normally open, when the driver steps on the brake pedal, the outlet of the proportional relay valve is communicated with the inlet, the first outlet of the EBS single-channel module is communicated with the second outlet, the gas pressure of the outlet of the electronic brake system reaches the front axle left ABS solenoid valve, the gas pressure of the outlet of the proportional relay valve and the control port gas pressure are in a first pressure corresponding relationship, and the front axle is braked, so that the residual braking efficiency under the failure of the front axle energy supply pipeline is ensured, and the redundant braking effect is achieved.

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