Braking system and method for unmanned driving of port container truck

Abstract

The invention discloses an unmanned braking system and method for a port container truck. The unmanned braking system comprises a first service braking device, and the first service braking device is connected with a first service braking energy accumulator used for providing high-pressure oil for the first service braking device and a first electro-hydraulic proportional valve used for adjusting the braking oil pressure of the first service braking device; the second service braking device is connected with a second service braking energy accumulator used for providing high-pressure oil for the second service braking device and a second electro-hydraulic proportional valve used for adjusting the braking oil pressure of the second service braking device. The parking braking device is connected with a parking braking energy accumulator used for providing high-pressure oil for the parking braking device and a parking braking electromagnetic valve used for controlling the parking braking energy accumulator to implement or release the parking braking energy accumulator, and when the parking braking electromagnetic valve loses power, the parking braking device automatically conducts parking braking. The system is provided with redundant backup of braking, when one braking loop breaks down, pressurizing and control of other braking loops are not affected, and the braking safety is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of off-road vehicle braking, and in particular to a braking system and method for an unmanned port container truck. Background Art

[0002] With the rapid development of global intelligent technology, the intelligentization of domestic and foreign ports has entered a period of rapid transformation. Important coastal ports have been planning the construction of smart ports and continuously promoting the transformation of port shipping technology. At present, most port transportation uses traditional container trucks. In the current economic downturn and labor shortage situation, the high wage cost of truck drivers is a big challenge for port operations; and the port automation transportation solution mainly uses automatic guided AGV transport vehicles, but this solution has very high requirements for port infrastructure, and the fixed track is difficult to replace. At the same time, the manufacturing cost is high, which is not conducive to the intelligent and flexible characteristics of modern logistics; the demand for unmanned driving technology in ports has become increasingly urgent.

[0003] At present, some manufacturers are developing and producing unmanned container trucks, and have realized unmanned trial operation of unmanned container trucks in ports. For example, the Chinese invention patent (publication number: CN118107536A) discloses a service brake device and method based on the hydraulic brake system of unmanned container trucks. The relevant braking technology is that when the vehicle receives a braking command, the accumulator solenoid valve, the service brake solenoid valve, and the proportional pressure reducing valve are energized respectively, and the hydraulic station works to charge the accumulator first. When the accumulator pressure reaches the set value, the accumulator solenoid valve loses power, and the accumulator oil pressure is maintained for emergency braking; then the hydraulic pump continues to work, and by adjusting the current of the proportional pressure reducing valve, the size of the brake oil pressure is controlled to achieve service braking; when the service brake valve and the electro-hydraulic proportional valve lose power, the brake is released.

[0004] However, the above-mentioned prior art provides a service braking device and method based on the hydraulic braking system of an unmanned container truck. When any one of the hydraulic pump, accumulator, proportional pressure reducing valve and service brake solenoid valve of the vehicle fails during driving, the entire vehicle will lose its braking ability, posing a safety hazard; and the emergency braking of its accumulator can only be activated when the vehicle has power. When the power of the vehicle is suddenly cut off, the accumulator solenoid valve cannot be opened, and the emergency braking effect cannot be achieved, posing a safety hazard.

[0005] Therefore, it is necessary to improve the existing technology. Summary of the invention

[0006] The purpose of the present invention is to solve the problem in the prior art that when any one of the hydraulic pump, accumulator, proportional pressure reducing valve and service brake solenoid valve of the unmanned container truck fails, the entire vehicle will lose braking ability, posing a safety hazard, and to propose a braking system and method for an unmanned port container truck.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A brake system for an unmanned port container truck comprises a hydraulic oil tank for storing hydraulic oil, the hydraulic oil tank being connected to a hydraulic pump; further comprising: a first service brake device for realizing service brakes of a first axle and a second axle of the container truck, the first service brake device being connected to a first service brake accumulator for providing high-pressure oil thereto and a first electro-hydraulic proportional valve for adjusting the brake oil pressure thereof; a second service brake device for realizing service brakes of a third axle and a fourth axle of the container truck, the second service brake device being connected to a second service brake accumulator for providing high-pressure oil thereto and a second electro-hydraulic proportional valve for adjusting the brake oil pressure thereof; a parking brake device for realizing parking brakes of the entire container truck, the parking brake device being connected to a parking brake accumulator for providing high-pressure oil thereto and a parking brake solenoid valve for controlling the implementation or release thereof, and when the parking brake solenoid valve loses power, the parking brake device automatically performs parking brakes; and a charging valve group for respectively charging the first service brake accumulator, the second service brake accumulator and the parking brake accumulator.

[0008] Furthermore, the filling valve group includes a filling valve and a three-position three-way sequence valve, and the total oil outlet of the filling valve is connected to the filling port of the three-position three-way sequence valve; the filling valve group also includes an emergency brake action switch, the electrical end of the emergency brake action switch is connected to the parking brake solenoid valve, and the oil pressure end of the emergency brake action switch is connected to the filling port of the three-position three-way sequence valve. When the oil pressure of the first service brake accumulator and / or the second service brake accumulator drops to a limit value N, the emergency brake action switch acts on the parking brake solenoid valve, causing the parking brake device to perform parking braking.

[0009] Furthermore, it also includes a vehicle controller VCU and a brake controller ECU. The vehicle controller VCU is used to send a deceleration requirement to the brake controller ECU. The brake controller ECU is electrically connected to a load sensor, an angle sensor and a wheel speed sensor. The first electro-hydraulic proportional valve, the second electro-hydraulic proportional valve and the parking brake solenoid valve are respectively controlled by the brake controller ECU.

[0010] Furthermore, the three-position three-way sequential valve includes an oil outlet A for charging the first service brake accumulator and an oil outlet B for charging the second service brake accumulator, and the charging valve includes an oil outlet C for charging the parking brake accumulator.

[0011] Furthermore, when the parking brake solenoid valve is energized, the parking brake device is connected to the parking brake accumulator, and the parking brake device releases the parking brake; when the parking brake solenoid valve loses power, the parking brake device is connected to the hydraulic oil tank, and the parking brake device performs parking braking.

[0012] Further, a first oil pressure sensor is provided between the first electro-hydraulic proportional valve and the first service brake device for detecting the oil pressure of the first service brake device; a second oil pressure sensor is provided between the second electro-hydraulic proportional valve and the second service brake device for detecting the oil pressure of the second service brake device.

[0013] A braking method for a braking system of an unmanned port container truck, the filling valve group further includes a low-pressure alarm device, and the low-pressure alarm device is connected to the filling port of the three-position three-way sequence valve; the method includes: Step 1, after the vehicle is powered on, check whether the low-pressure alarm device of the filling valve group alarms. If so, start the hydraulic pump, and the filling valve group pressurizes the first service brake accumulator and the second service brake accumulator until the low-pressure alarm device解除 the low-pressure alarm; if not, the brake controller ECU controls the hydraulic pump to operate at low pressure; Step 2, when the vehicle receives a driving command, the brake controller ECU controls the parking brake solenoid valve to be powered on, so that the parking brake device releases the parking brake and the vehicle starts to drive; Step 3, during the vehicle's driving, the vehicle controller VCU sends a braking command of deceleration g to the brake controller ECU, and the brake controller ECU collects information from the load sensor, the angle sensor and the wheel speed sensor, and calculates the required braking oil pressure h; Step 4, the brake controller ECU controls the first electro-hydraulic proportional valve and the second electro-hydraulic proportional valve to regulate the braking oil pressure of the first service brake device and the second service brake device; Step 5, the brake controller ECU collects the braking oil pressure data of the first service brake device and the second service brake device to obtain the braking oil pressure H; Step 6, the brake controller ECU compares the collected braking oil pressure H with the required braking oil pressure h; if the oil pressure H - the oil pressure h ≤ m1, or the oil pressure H - the oil pressure h ≥ m2, execute Step 4 - Step 5, if m1 < the oil pressure H - the oil pressure h < m2, the braking requirement of the brake controller ECU is completed; Step 7, the brake controller ECU collects the actual deceleration G and compares the actual deceleration G with the required deceleration g; if the deceleration G - the deceleration g ≥ M1, or the deceleration G - the deceleration g ≤ M2, execute Step 4 - Step 6, if M1 > the deceleration G - the deceleration g > M2, the deceleration requirement of the vehicle controller VCU is completed and feedback to the vehicle controller VCU.

[0014] Further, it further includes the following steps: Step 8A, during the vehicle's driving, after the vehicle stops by service braking, if the continuous braking time of the first service brake device and the second service brake device exceeds the set duration T, the brake controller ECU controls the parking brake solenoid valve to lose power, and then the parking brake device performs parking braking.

[0015] Furthermore, the following steps are included: Step 8B, when the oil pressure of the first service brake accumulator and / or the second service brake accumulator drops to a limit value M, the low pressure alarm device sounds an alarm; when the oil pressure of the first service brake accumulator and / or the second service brake accumulator drops to a limit value N, the emergency brake action switch acts on the parking brake solenoid valve, causing the parking brake solenoid valve to lose power, thereby causing the parking brake device to perform parking braking.

[0016] Furthermore, the parking brake solenoid valve is connected to a manual hydraulic pump and an oil pressure gauge, the manual hydraulic pump is used to manually charge the parking brake accumulator, the parking brake solenoid valve is provided with a manual override button, which is used to manually release the brakes of the parking brake device, and also includes the following steps: Step 8C, when the entire vehicle fails and needs to be towed away for repair, the parking brake accumulator is charged by the manual hydraulic pump until the oil pressure displayed on the oil pressure gauge reaches a set value and then the charging is stopped; the brakes of the parking brake device are then released by the manual override button.

[0017] After adopting the above structure, the beneficial effects of the present invention are: (1) The unmanned braking system of a port container truck described in the present invention comprises a first service brake device for realizing service braking of a first axle and a second axle of the container truck, wherein the first service brake device is connected to a first service brake accumulator for supplying high-pressure oil thereto and a first electro-hydraulic proportional valve for regulating the brake oil pressure thereof; a second service brake device for realizing service braking of a third axle and a fourth axle of the container truck, wherein the second service brake device is connected to a second service brake accumulator for supplying high-pressure oil thereto and a second electro-hydraulic proportional valve for regulating the brake oil pressure thereof; a parking brake device for realizing parking braking of the entire container truck, wherein the parking brake device is connected to a parking brake accumulator for supplying high-pressure oil thereto and a parking brake solenoid valve for controlling the implementation or release thereof, and when the parking brake solenoid valve loses power, the parking brake device automatically performs parking braking. The present invention is provided with redundant backup of brakes. The charging devices and control devices of the first service brake device, the second service brake device and the parking brake device are independently provided. When one of the brake circuits fails, the charging and control of other brake circuits are not affected, which greatly improves the safety of braking. When the whole vehicle loses power, the parking brake solenoid valve also loses power, so that the parking brake device automatically performs parking brake, which further improves the safety of braking.

[0018] (2) In the unmanned braking system of a port container truck described in the present invention, the filling valve group includes a filling valve and a three-position three-way sequence valve, and the total oil outlet of the filling valve is connected to the filling port of the three-position three-way sequence valve; the filling valve group also includes an emergency brake action switch, the electrical end of the emergency brake action switch is connected to the parking brake solenoid valve, and the oil pressure end of the emergency brake action switch is connected to the filling port of the three-position three-way sequence valve. When the oil pressure of the first service brake accumulator and / or the second service brake accumulator drops to a limit value N, the emergency brake action switch acts on the parking brake solenoid valve, causing the parking brake solenoid valve to lose power, thereby causing the parking brake device to perform parking braking. The present invention is provided with a redundant backup of braking. When the braking functions of the first service brake device and the second service brake device are normal, a closed-loop control output brake oil pressure is formed by the first electro-hydraulic proportional valve and the second electro-hydraulic proportional valve to achieve precise control of vehicle deceleration and parking; when the first service brake device and / or the second service brake device fails, and the oil pressure of the first service brake accumulator and / or the second service brake accumulator is lower than the safety requirement, the emergency brake action switch acts on the parking brake solenoid valve, causing the parking brake solenoid valve to lose power, thereby causing the parking brake device to perform parking braking to ensure safe parking of the vehicle.

[0019] (3) In the unmanned braking system of a port container truck described in the present invention, the filling valve group also includes a low-pressure alarm device, which is connected to the filling port of the three-position three-way sequence valve. When the low-pressure alarm device sounds an alarm, the hydraulic pump is started, and the filling port of the filling valve pressurizes the first service brake accumulator and the second service brake accumulator until the low-pressure alarm device releases the low-pressure alarm. At this time, the brake controller ECU controls the hydraulic pump to switch to low-pressure operation. The feedback control of the low-pressure alarm device can realize intermittent operation of the hydraulic pump, thereby effectively saving energy consumption, conforming to the concept of green energy saving, and effectively extending the service life of system components.

[0020] (4) In the unmanned braking system of a port container truck described in the present invention, the parking brake solenoid valve is connected to a manual hydraulic pump and an oil pressure gauge, the manual hydraulic pump is used to manually charge the parking brake accumulator, and the parking brake solenoid valve is provided with a manual override button for manually releasing the brake of the parking brake device. When the whole vehicle fails and needs to be towed away for repair, the parking brake accumulator is manually charged by the manual hydraulic pump until the oil pressure displayed on the oil pressure gauge reaches the set value, and then the parking brake device is released by the manual override button, so that the whole vehicle can be towed away for repair.

[0021] (5) The braking method of the unmanned braking system of a port container truck described in the present invention also includes a vehicle controller VCU and a brake controller ECU. The vehicle controller VCU is used to send a deceleration demand to the brake controller ECU. The brake controller ECU is electrically connected to a load sensor, an angle sensor and a wheel speed sensor. The first electro-hydraulic proportional valve, the second electro-hydraulic proportional valve and the parking brake solenoid valve are respectively controlled by the brake controller ECU. When the vehicle is driving, the vehicle controller VCU sends a braking command of a deceleration g to the brake controller ECU. The brake controller ECU calculates the required brake oil pressure h according to the braking command of the deceleration g of the vehicle controller VCU and in combination with the weight, speed, slope and other information of the vehicle, and then controls the first electro-hydraulic proportional valve and the second electro-hydraulic proportional valve to regulate the brake oil pressure of the first service brake device and the second service brake device. The first oil pressure sensor collects the brake oil pressure data of the first service brake device, and the second oil pressure sensor collects the brake oil pressure data of the second service brake device, and then feeds back the collected actual brake oil pressure H to the brake controller ECU; the brake controller ECU compares the brake oil pressure H collected by the first oil pressure sensor and the second oil pressure sensor with the required brake oil pressure h. If the oil pressure H-oil pressure h≤m1, or the oil pressure H-oil pressure h≥m2, the above control process is repeated until the brake oil pressure reaches the braking requirement. At the same time, the brake controller ECU collects the actual deceleration G and compares it with the required deceleration g. If deceleration G-deceleration g≥M1, or deceleration G-deceleration g≤M2, the above control process is repeated until the deceleration reaches the required value, thus realizing closed-loop control. As above, deceleration and parking are accurately realized according to the braking requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the specific embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a structural principle diagram of the present invention; Figure 2 It is a structural principle diagram of the liquid filling valve group of the present invention; Figure 3 It is the control principle diagram of the present invention.

[0024] Figures 1 to 3 The bid number is: 1. Hydraulic oil tank; 11. Hydraulic pump; 12. Low-pressure filter; 2. First service brake device; 21. First service brake accumulator; 22. First electro-hydraulic proportional valve; 221. Service brake light switch; 23. First oil pressure sensor; 3. Second service brake device; 31. Second service brake accumulator; 32. Second electro-hydraulic proportional valve; 321. Parking brake light switch; 33. Second oil pressure sensor; 4. Parking brake device; 41. Parking brake accumulator; 42. Parking brake solenoid valve; 421. Manual hydraulic pump; 422, oil pressure gauge; 43, pressure reducing valve; 5, filling valve group; 51, filling valve; 511, oil outlet C; 5111, one-way valve; 52, three-position three-way sequential valve; 521, filling port; 522, oil outlet A; 523, oil outlet B; 53, emergency brake action switch; 54, low pressure alarm device; 6, pressure measuring connector; 80, vehicle controller VCU; 90, brake controller ECU; 100, first axis; 101, second axis; 102, third axis; 103, fourth axis. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0026] In the description of the present invention, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0027] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, if the term "plurality" appears, the term "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0028] In the present invention, unless otherwise clearly defined and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In the present invention, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or the like, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0030] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If present, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in the present invention are for illustrative purposes only and do not represent the only implementation method.

[0031] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0032] like Figure 1 and Figure 2As shown, a brake system for an unmanned port container truck includes a hydraulic oil tank 1 for storing hydraulic oil, and the hydraulic oil tank 1 is connected to a hydraulic pump 11; it also includes a first service brake device 2 for realizing service braking of a first shaft 100 and a second shaft 101 of the container truck, and the first service brake device 2 is connected to a first service brake accumulator 21 for providing high-pressure oil thereto, and a first electro-hydraulic proportional valve 22 for adjusting the brake oil pressure thereof; a second service brake device 3 for realizing service braking of a third shaft 102 and a fourth shaft 103 of the container truck, and the second service brake device 3 is connected to A second service brake accumulator 31 for providing high-pressure oil thereto, and a second electro-hydraulic proportional valve 32 for adjusting the brake oil pressure thereto; a parking brake device 4 for realizing parking brake of the entire truck, the parking brake device 4 is connected with a parking brake accumulator 41 for providing high-pressure oil thereto, and a parking brake solenoid valve 42 for controlling the implementation or release thereof, and when the parking brake solenoid valve 42 loses power, the parking brake device 4 automatically performs parking brake; a charging valve group 5 for respectively charging the first service brake accumulator 21, the second service brake accumulator 31 and the parking brake accumulator 41. A first oil pressure sensor 23 is provided between the first electro-hydraulic proportional valve 22 and the first service brake device 2, for detecting the oil pressure of the first service brake device 2; a second oil pressure sensor 33 is provided between the second electro-hydraulic proportional valve 32 and the second service brake device 3, for detecting the oil pressure of the second service brake device 3. The first electro-hydraulic proportional valve 22 is arranged between the first service brake accumulator 21 and the first service brake device 2, and is used to adjust the oil pressure charged into the first service brake device 2; the second electro-hydraulic proportional valve 32 is arranged between the second service brake accumulator 31 and the second service brake device 3, and is used to adjust the oil pressure charged into the second service brake device 3; the parking brake solenoid valve 42 is used to control the parking brake device 4 to be connected with the parking brake accumulator 41, or to be connected with the hydraulic oil tank 1.

[0033] Based on the above embodiments, the present invention aims to provide an unmanned braking system for a port container truck, comprising a first service brake device 2 for realizing service braking of a first axle 100 and a second axle 101 of the container truck, wherein the first service brake device 2 is connected to a first service brake accumulator 21 for providing high-pressure oil thereto, and a first electro-hydraulic proportional valve 22 for adjusting the brake oil pressure thereof; a second service brake device 3 for realizing service braking of a third axle 102 and a fourth axle 103 of the container truck, wherein the second service brake device 3 is connected to a second service brake accumulator 31 for providing high-pressure oil thereto, and a second electro-hydraulic proportional valve 32 for adjusting the brake oil pressure thereof; a parking brake device 4 for realizing parking braking of the entire container truck, wherein the parking brake device 4 is connected to a parking brake accumulator 41 for providing high-pressure oil thereto, and a parking brake solenoid valve 42 for controlling the implementation or release thereof, and when the parking brake solenoid valve 42 loses power, the parking brake device 4 automatically performs parking braking. The present invention is provided with redundant backup of brakes. The charging and control of the first service brake device 2, the second service brake device 3 and the parking brake device 4 are independently set. When one of the brake circuits fails, the charging and control of other brake circuits are not affected, which greatly improves the safety of braking. When the whole vehicle loses power, the parking brake solenoid valve 42 also loses power, so that the parking brake device 4 automatically performs parking brake, which further improves the safety of braking.

[0034] In this embodiment, the oil outlet of the hydraulic pump 11 is connected to the charging valve group 5, and the first service brake accumulator 21, the second service brake accumulator 31 and the parking brake accumulator 41 are pressurized through the charging valve group 5; the first service brake accumulator 21 is connected to the first electro-hydraulic proportional valve 22, and the first electro-hydraulic proportional valve 22 adjusts the oil pressure charged into the first service brake device 2 after receiving the signal from the brake controller ECU90, thereby realizing the service braking of the first axle 100 and the second axle 101 of the container truck; a first oil pressure sensor 23 is provided between the first electro-hydraulic proportional valve 22 and the first service brake device 2, and the first oil pressure sensor 23 is used to detect the oil pressure of the first service brake device 2. The second service brake accumulator 31 is connected to the second electro-hydraulic proportional valve 32. After receiving the signal from the brake controller ECU90, the second electro-hydraulic proportional valve 32 adjusts the oil pressure charged into the second service brake device 3, thereby realizing the service brake of the third shaft 102 and the fourth shaft 103 of the truck; a second oil pressure sensor 33 is provided between the second electro-hydraulic proportional valve 32 and the second service brake device 3, and the second oil pressure sensor 33 is used to detect the oil pressure of the second service brake device 3. The parking brake accumulator 41 is connected to the parking brake solenoid valve 42. A pressure reducing valve 43 is provided between the parking brake solenoid valve 42 and the parking brake device 4, which is used to ensure that the working oil pressure of the parking brake device 4 is not higher than the safe working oil pressure, thereby protecting the parking brake device 4.

[0035] In a further embodiment, the first electro-hydraulic proportional valve 22 is electrically connected to a driving brake light and a driving brake light switch 221 for controlling the driving brake light; the parking brake solenoid valve 42 is electrically connected to a parking brake light and a parking brake light switch 321 for controlling the parking brake light. The driving brake light facilitates the observation of the working state of the first driving brake device 2, and the parking brake light facilitates the observation of the working state of the parking brake device 4. In a further embodiment, the hydraulic oil tank 1 is integrated with a low-pressure filter 12, and the low-pressure filter 12 is connected to the oil suction port of the hydraulic pump 11, and the oil passing through is filtered by the low-pressure filter 12, so as to ensure the stability and reliability of the operation of the braking system. In a further embodiment, the braking system also includes a plurality of pressure measuring joints 6, and the pressure measuring joints 6 are used to detect the oil pressure value of the installation point, so as to facilitate the diagnosis and analysis of the fault when the braking system fails in the later stage.

[0036] As another preferred embodiment of the present invention, the filling valve group 5 includes a filling valve 51 and a three-position three-way sequence valve 52, and the total oil outlet of the filling valve 51 is connected to the filling port 521 of the three-position three-way sequence valve 52; the filling valve group 5 also includes an emergency brake action switch 53, the electrical end of the emergency brake action switch 53 is connected to the parking brake solenoid valve 42, and the oil pressure end of the emergency brake action switch 53 is connected to the filling port 521 of the three-position three-way sequence valve 52. When the oil pressure of the first service brake accumulator 21 and / or the second service brake accumulator 31 drops to the limit value N, the emergency brake action switch 53 acts on the parking brake solenoid valve 42, so that the parking brake device 4 performs parking braking. When the parking brake solenoid valve 42 is energized, the parking brake device 4 is connected to the parking brake accumulator 41, and the parking brake device 4 releases the parking brake; when the parking brake solenoid valve 42 is de-energized, the parking brake device 4 is connected to the hydraulic oil tank 1, and the parking brake device 4 performs the parking brake. Figure 2As shown, the present invention is provided with a redundant backup of braking. When the braking functions of the first service brake device 2 and the second service brake device 3 are normal, the brake oil pressure input to the first service brake device 2 and the second service brake device 3 is controlled by the first electro-hydraulic proportional valve 22 and the second electro-hydraulic proportional valve 32 to achieve precise control of vehicle deceleration and parking; when the oil pressure of the first service brake accumulator 21 and / or the second service brake accumulator 31 drops to the limit value N, the emergency brake action switch 53 acts on the parking brake solenoid valve 42, causing the parking brake solenoid valve 42 to lose power, thereby connecting the parking brake device 4 to the hydraulic oil tank 1. At this time, the parking brake device 4 performs parking braking to ensure safe parking of the vehicle. In this embodiment, the oil pressure end of the emergency brake action switch 53 is connected to the filling port 521 of the three-position three-way sequence valve 52. When the oil pressures of the first service brake accumulator 21 and the second service brake accumulator 31 are equal, the filling port 521 of the three-position three-way sequence valve 52 is connected to both the oil outlet A522 and the oil outlet B523; when the oil pressures of the first service brake accumulator 21 and the second service brake accumulator 31 are not equal, the filling port 521 of the three-position three-way sequence valve 52 is connected to the low-pressure oil outlet. When the oil pressure of the first service brake accumulator 21 and / or the second service brake accumulator 31 decreases, the filling port 521 of the three-position three-way sequential valve 52 is connected to the low-pressure oil outlet. When the oil pressure decreases to the limit value M, the low-pressure alarm device issues a warning. When the oil pressure continues to decrease to the limit value N, the emergency brake action switch 53 is triggered. The emergency brake action switch 53 acts on the parking brake solenoid valve 42, causing the parking brake solenoid valve 42 to lose power, thereby connecting the parking brake device 4 to the hydraulic oil tank 1. At this time, the parking brake device 4 performs parking braking to ensure safe parking of the vehicle.

[0037] In a further embodiment, the emergency brake action switch 53 is electrically connected to the hydraulic pump 11. When the oil pressure of the hydraulic pump 11 drops to a limit value N, the emergency brake action switch 53 acts on the parking brake solenoid valve 42, causing the parking brake solenoid valve 42 to lose power, thereby causing the parking brake device 4 to be connected to the hydraulic oil tank 1. At this time, the parking brake device 4 performs parking braking to ensure safe parking of the vehicle.

[0038] In a further embodiment, when the three-position three-way sequence valve 52 is in the first position, the three-position three-way sequence valve 52 charges the first service brake accumulator 21 through the oil outlet A522; when the three-position three-way sequence valve 52 is in the second position, the three-position three-way sequence valve 52 charges the first service brake accumulator 21 through the oil outlet A522 and charges the second service brake accumulator 31 through the oil outlet B523; when the three-position three-way sequence valve 52 is in the third position, the three-position three-way sequence valve 52 charges the second service brake accumulator 31 through the oil outlet B523. In this embodiment, Figure 2 As shown, the automatic adjustment function of the three-position three-way sequence valve 52 realizes balanced charging of the first service brake accumulator 21 and the second service brake accumulator 31, thereby ensuring balanced operation of the first service brake device 2 and the second service brake device 3.

[0039] In a further embodiment, a one-way valve 5111 is connected in series between the total oil outlet and the oil outlet C511 of the charging valve 51 to maintain the pressure of the parking brake accumulator 41 after charging.

[0040] As another preferred embodiment of the present invention, it also includes a vehicle controller VCU80 and a brake controller ECU90, wherein the vehicle controller VCU80 is used to send a deceleration demand to the brake controller ECU90, and the brake controller ECU90 is electrically connected to a load sensor, an angle sensor, and a wheel speed sensor, and the first electro-hydraulic proportional valve 22, the second electro-hydraulic proportional valve 32, and the parking brake solenoid valve 42 are respectively controlled by the brake controller ECU90. In this embodiment, Figure 1 As shown, the braking system is controlled by the vehicle controller VCU80 and the brake controller ECU90 to accurately achieve vehicle deceleration and parking.

[0041] like Figures 1 to 3As shown, the present invention further provides a braking method for a braking system of driverless port container trucks. The liquid filling valve group 5 further includes a low-pressure alarm device 54, and the low-pressure alarm device 54 is connected to the liquid filling port 521 of the three-position three-way sequence valve 52. The method includes: Step 1, after the vehicle is powered on, check whether the low-pressure alarm device 54 of the liquid filling valve group 5 alarms. If it does, start the hydraulic pump 11, and the liquid filling valve group 5 pressurizes the first service brake accumulator 21 and the second service brake accumulator 31 until the low-pressure alarm device 54解除 the low-pressure alarm. If not, the brake controller ECU90 controls the hydraulic pump 11 to operate at low pressure; Step 2, when the vehicle receives a driving instruction, the brake controller ECU90 controls the parking brake solenoid valve 42 to be powered on, so that the parking brake device 4 releases the parking brake and the vehicle starts to drive; Step 3, during the vehicle's driving, the vehicle controller VCU80 sends a braking instruction of deceleration g to the brake controller ECU90. The brake controller ECU90 collects information from the load sensor, the angle sensor, and the wheel speed sensor, and calculates the required braking oil pressure h; Step 4, the brake controller ECU90 controls the first electro-hydraulic proportional valve 22 and the second electro-hydraulic proportional valve 32 to regulate the braking oil pressure of the first service brake device 2 and the second service brake device 3; Step 5, the brake controller ECU90 collects the braking oil pressure data of the first service brake device 2 and the second service brake device 3 to obtain the braking oil pressure H; Step 6, the brake controller ECU90 compares the collected braking oil pressure H with the required braking oil pressure h. If the oil pressure H - oil pressure h ≤ m1, or the oil pressure H - oil pressure h ≥ m2, execute Steps 4 - 5. If m1 < oil pressure H - oil pressure h < m2, the braking requirement of the brake controller ECU90 is completed; Step 7, the brake controller ECU90 collects the actual deceleration G and compares the actual deceleration G with the required deceleration g. If the deceleration G - deceleration g ≥ M1, or the deceleration G - deceleration g ≤ M2, execute Steps 4 - 6. If M1 > deceleration G - deceleration g > M2, the deceleration requirement of the vehicle controller VCU80 is completed and feedback is sent to the vehicle controller VCU80.

[0042] It should be noted that there may be some inaccuracies in the translation due to the lack of clear understanding of some terms in the original text. It is recommended to further check and correct according to the specific technical content.Based on the above embodiments, the present invention aims to provide a braking method for an unmanned braking system of a port container truck. When the vehicle is driving, the vehicle controller VCU80 sends a braking command of a deceleration g to the brake controller ECU90. The brake controller ECU90 calculates the required brake oil pressure h according to the braking command of the deceleration g of the vehicle controller VCU80, combined with the weight, speed, slope and other information of the vehicle, and then controls the first electro-hydraulic proportional valve 22 and the second electro-hydraulic proportional valve 32 to regulate the brake oil pressure of the first service brake device 2 and the second service brake device 3. The first oil pressure sensor 23 collects the brake oil pressure data of the first service brake device 2, and the second oil pressure sensor 33 collects the brake oil pressure data of the second service brake device 3, and then feeds back the collected actual brake oil pressure H to the brake controller ECU90; the brake controller ECU90 compares the brake oil pressure H collected by the first oil pressure sensor 23 and the second oil pressure sensor 33 with the required brake oil pressure h. If the oil pressure H-oil pressure h≤m1, or the oil pressure H-oil pressure h≥m2, repeat the above control process until the brake oil pressure reaches the braking requirement. It should be noted here that regardless of whether the condition of m1> oil pressure H- oil pressure h> m2 is met, the first service brake device 2 and the second service brake device 3 will perform braking action according to the brake oil pressure H, thereby generating a deceleration G. At the same time, the brake controller ECU90 collects the actual deceleration G and then compares it with the required deceleration g. If the deceleration G-deceleration g≥M1, or the deceleration G-deceleration g≤M2, the above control process is repeated until the deceleration reaches the requirement, thereby realizing closed-loop control. As above, deceleration and parking are accurately achieved according to the braking requirements. In this embodiment, the vehicle controller VCU80 collects the final deceleration in order to prepare for sending the deceleration requirement to the brake controller ECU90 next time.

[0043] In this embodiment, Figure 3The brake controller ECU90 mentioned in the description is the same unit, and is listed multiple times for the convenience of displaying the logical order. In this embodiment, the brake controller ECU90 calculates the required brake oil pressure h according to the brake instruction of the deceleration g of the vehicle controller VCU80, combined with the weight, speed, slope and other information of the vehicle. The brake controller ECU90 controls the current of the first electro-hydraulic proportional valve 22 and the second electro-hydraulic proportional valve 32 through the PWM signal, and regulates the output oil pressure of the first electro-hydraulic proportional valve 22 and the second electro-hydraulic proportional valve 32, thereby realizing the control of the brake oil pressure of the first service brake device 2 and the second service brake device 3; the first oil pressure sensor 23 collects the brake oil pressure data of the first service brake device 2, and the second oil pressure sensor 33 collects the brake oil pressure data of the second service brake device 3. The actual brake oil pressure H data collected is then converted into an analog voltage signal and fed back to the brake controller ECU90. The brake controller ECU90 compares the brake oil pressure H collected by the first oil pressure sensor 23 and the second oil pressure sensor 33 with the required brake oil pressure h. If the oil pressure H-oil pressure h≤m1, or the oil pressure H-oil pressure h≥m2, the above control process is repeated until the brake oil pressure reaches the braking requirement.

[0044] As another preferred embodiment of the present invention, the following steps are also included: Step 8A, during the driving process of the vehicle, after the vehicle is stopped by the service brake, the first service brake device 2 and the second service brake device 3 continue to brake for more than the set time T, and the brake controller ECU90 controls the parking brake solenoid valve 42 to lose power, thereby causing the parking brake device 4 to perform parking brake. In this embodiment, this design is used to automatically start the parking brake when the vehicle is stopped by the service brake for a long time; when the vehicle is parked, the first service brake device 2 and the second service brake device 3 release the brake, thereby preventing the vehicle from being in the service brake state for a long time, affecting the service life of the first service brake device 2 and the second service brake device 3.

[0045] As another preferred embodiment of the present invention, the following steps are also included: Step 8B, when the oil pressure of the first service brake accumulator 21 and / or the second service brake accumulator 31 drops to the limit value M, the low pressure alarm device 54 alarms; when the oil pressure of the first service brake accumulator 21 and / or the second service brake accumulator 31 drops to the limit value N, the emergency brake action switch 53 acts on the parking brake solenoid valve 42, causing the parking brake solenoid valve 42 to lose power, thereby causing the parking brake device 4 to perform parking braking. In this embodiment, when the oil pressure of the first service brake accumulator 21 and / or the second service brake accumulator 31 drops to the limit value M, the low pressure alarm device 54 gives an alarm to remind personnel to perform maintenance; when the oil pressure of the first service brake accumulator 21 and / or the second service brake accumulator 31 drops to the limit value N, the emergency brake action switch 53 acts on the parking brake solenoid valve 42, causing the parking brake solenoid valve 42 to lose power, thereby causing the parking brake device 4 to perform parking brake. When the first service brake device 2 and / or the second service brake device 3 fails, the parking brake device 4 can automatically perform parking brake, ensuring the safety of parking brake.

[0046] As another preferred embodiment of the present invention, the parking brake solenoid valve 42 is connected to a manual hydraulic pump 421 and an oil pressure gauge 422. The manual hydraulic pump 421 is used to manually charge the parking brake accumulator 41. The parking brake solenoid valve 42 is provided with a manual override button (not shown in the figure) for manually releasing the parking brake device 4. The steps include: Step 8C, when the vehicle fails and needs to be towed away for repair, the parking brake accumulator 41 is charged by the manual hydraulic pump 421 until the oil pressure displayed by the oil pressure gauge 422 reaches the set value and then the charging is stopped; the parking brake device 4 is released by the manual override button. In this embodiment, Figure 2 As shown, when the whole vehicle fails and needs to be towed away for repair, the oil pressure of the parking brake accumulator 41 is observed through the oil pressure gauge 422. If the oil pressure of the parking brake accumulator 41 is greater than the oil pressure of the parking brake device 4, the manual override button is manually pressed to release the parking brake of the vehicle, and the vehicle can be towed away for repair; if the oil pressure of the parking brake accumulator 41 is less than the oil pressure of the parking brake device 4, the parking brake accumulator 41 is pressurized by the manual hydraulic pump 421, and the oil pressure on the oil pressure gauge 422 stops after reaching the set value, and then the manual override button is pressed to release the parking brake of the vehicle, and the vehicle can be towed away for repair.

[0047] Obviously, the above embodiments are merely examples for clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from them are still within the protection scope of the present invention.

Claims

1. A brake system for an unmanned port container truck, comprising a hydraulic oil tank (1) for storing hydraulic oil, wherein the hydraulic oil tank (1) is connected to a hydraulic pump (11); characterized in that: Also includes: A first service brake device (2) for achieving service brakes on a first shaft (100) and a second shaft (101) of a container truck, wherein the first service brake device (2) is connected to a first service brake accumulator (21) for supplying high-pressure oil thereto, and a first electro-hydraulic proportional valve (22) for adjusting the brake oil pressure thereof; A second service brake device (3) for achieving service brakes on the third axle (102) and the fourth axle (103) of the container truck, the second service brake device (3) being connected to a second service brake accumulator (31) for supplying high-pressure oil thereto, and a second electro-hydraulic proportional valve (32) for regulating the brake oil pressure thereof; A parking brake device (4) is used to implement parking brake of the entire container truck, the parking brake device (4) is connected to a parking brake accumulator (41) for providing high-pressure oil thereto, and a parking brake solenoid valve (42) for controlling the implementation or release thereof, and when the parking brake solenoid valve (42) loses power, the parking brake device (4) automatically performs parking brake; The charging valve group (5) is used to charge the first service brake accumulator (21), the second service brake accumulator (31) and the parking brake accumulator (41) respectively.

2. The unmanned braking system for port container trucks according to claim 1 is characterized by: The charging valve group (5) comprises a charging valve (51) and a three-position three-way sequence valve (52), wherein a total oil outlet of the charging valve (51) is communicated with a charging port (521) of the three-position three-way sequence valve (52); the charging valve group (5) further comprises an emergency brake action switch (53), wherein an electrical end of the emergency brake action switch (53) is connected to a parking brake solenoid valve (42), and an oil pressure end of the emergency brake action switch (53) is connected to a charging port (521) of the three-position three-way sequence valve (52). When the oil pressure of the first service brake accumulator (21) and / or the second service brake accumulator (31) drops to a limit value N, the emergency brake action switch (53) acts on the parking brake solenoid valve (42), so that the parking brake device (4) performs parking braking.

3. The unmanned braking system for a port container truck according to claim 1 or 2, characterized in that: The invention also comprises a vehicle controller VCU (80) and a brake controller ECU (90), wherein the vehicle controller VCU (80) is used to send a deceleration demand to the brake controller ECU (90), the brake controller ECU (90) is electrically connected to a load sensor, an angle sensor and a wheel speed sensor, and the first electro-hydraulic proportional valve (22), the second electro-hydraulic proportional valve (32) and the parking brake solenoid valve (42) are respectively controlled by the brake controller ECU (90).

4. The unmanned braking system for port container trucks according to claim 2 is characterized by: The three-position three-way sequence valve (52) comprises an oil outlet A (522) for charging the first service brake accumulator (21) and an oil outlet B (523) for charging the second service brake accumulator (31), and the charging valve (51) comprises an oil outlet C (511) for charging the parking brake accumulator (41).

5. The unmanned braking system for port container trucks according to claim 1 is characterized by: When the parking brake solenoid valve (42) is energized, the parking brake device (4) is communicated with the parking brake accumulator (41), and at this time, the parking brake of the parking brake device (4) is released; when the parking brake solenoid valve (42) is de-energized, the parking brake device (4) is communicated with the hydraulic oil tank (1), and at this time, the parking brake device (4) performs parking brake.

6. The unmanned braking system for port container trucks according to claim 1 is characterized by: A first oil pressure sensor (23) is provided between the first electro-hydraulic proportional valve (22) and the first service brake device (2) for detecting the oil pressure of the first service brake device (2); a second oil pressure sensor (33) is provided between the second electro-hydraulic proportional valve (32) and the second service brake device (3) for detecting the oil pressure of the second service brake device (3).

7. A braking method using the unmanned braking system of a port container truck as claimed in claim 3, characterized in that: The fluid filling valve group (5) further includes a low-pressure alarm device (54), and the low-pressure alarm device (54) is connected to the fluid filling port (521) of the three-position three-way sequence valve (52); the method includes: Step 1, after the whole vehicle is powered on, whether the low-pressure alarm device (54) of the fluid filling valve group (5) alarms, If so, start the hydraulic pump (11), and the fluid filling valve group (5) pressurizes the first service brake accumulator (21) and the second service brake accumulator (31) until the low-pressure alarm device (54)解除 the low-pressure alarm; If not, the brake controller ECU (90) controls the hydraulic pump (11) to operate at low pressure; Step 2, when the whole vehicle receives a driving instruction, the brake controller ECU (90) controls the parking brake solenoid valve (42) to be energized so that the parking brake device (4) releases the parking brake and the vehicle travels; Step 3, during the vehicle's travel, the vehicle controller VCU (80) sends a braking instruction of deceleration g to the brake controller ECU (90), and the brake controller ECU (90) collects information from the load sensor, the angle sensor and the wheel speed sensor, and calculates the required braking oil pressure h; Step 4, the brake controller ECU (90) controls the first electro-hydraulic proportional valve (22) and the second electro-hydraulic proportional valve (32) to regulate the braking oil pressure of the first service brake device (2) and the second service brake device (3); Step 5, the brake controller ECU (90) collects the braking oil pressure data of the first service brake device (2) and the second service brake device (3) to obtain the braking oil pressure H; Step 6, the brake controller ECU (90) compares the collected braking oil pressure H with the required braking oil pressure h; If the oil pressure H - the oil pressure h ≤ m1, or the oil pressure H - the oil pressure h ≥ m2, execute Steps 4 - 5, If m1 < the oil pressure H - the oil pressure h < m2, complete the braking requirement of the brake controller ECU (90); Step 7, the brake controller ECU (90) collects the actual deceleration G and compares the actual deceleration G with the required deceleration g; If the deceleration G - the deceleration g ≥ M1, or the deceleration G - the deceleration g ≤ M2, execute Steps 4 - 6, If M1>deceleration G-deceleration g>M2, the deceleration requirement of the vehicle controller VCU (80) is completed and fed back to the vehicle controller VCU (80).

8. The braking method of the unmanned braking system of a port container truck according to claim 7, characterized in that: The following steps are also included: Step 8A: During vehicle travel, after the vehicle is stopped by service braking, the first service braking device (2) and the second service braking device (3) continue braking for a time period exceeding a set time period T, and the brake controller ECU (90) controls the parking brake solenoid valve (42) to lose power, thereby causing the parking brake device (4) to perform parking braking.

9. The braking method of the unmanned braking system of a port container truck according to claim 7, characterized in that: The following steps are also included: Step 8B: when the oil pressure of the first service brake accumulator (21) and / or the second service brake accumulator (31) drops to a limit value M, the low pressure alarm device (54) sounds an alarm; when the oil pressure of the first service brake accumulator (21) and / or the second service brake accumulator (31) drops to a limit value N, the emergency brake action switch (53) acts on the parking brake solenoid valve (42), causing the parking brake solenoid valve (42) to lose power, thereby causing the parking brake device (4) to perform parking braking.

10. The braking method of the unmanned braking system of a port container truck according to claim 7, characterized in that: The parking brake solenoid valve (42) is connected to a manual hydraulic pump (421) and an oil pressure gauge (422), the manual hydraulic pump (421) is used to manually charge the parking brake accumulator (41), the parking brake solenoid valve (42) is provided with a manual override button, which is used to manually release the parking brake device (4), and further comprises the following steps: Step 8C, when the vehicle fails and needs to be towed away for repair, the parking brake accumulator (41) is charged by the manual hydraulic pump (421) until the oil pressure displayed by the oil pressure gauge (422) reaches a set value and then the charging is stopped; then the parking brake device (4) is released by the manual override button.

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