Hydraulic brake system of mining dump truck

Abstract

The utility model discloses a hydraulic brake system of a mining dump truck, which comprises an oil source subsystem, a hydraulic control subsystem, a hydraulic control subsystem and an energy storage subsystem, and is characterized in that the oil source subsystem comprises a hydraulic oil tank, a gear pump, a double-loop prefill valve and an energy accumulator group which are sequentially connected; the service braking subsystem comprises a front axle service braking set, a middle and rear axle service braking set and a double-loop service braking valve set, and the double-loop service braking valve set comprises a double-loop foot braking valve and a double-loop electric proportional main braking valve which are arranged in parallel. The utility model discloses a mining dump truck. The oil source subsystem and the service braking subsystem are arranged, a plurality of pressure sensors are arranged, mechanical and unmanned braking can be achieved, the number of elements is small, reliability is high, the braking response speed and reliability are improved, and stable operation of the braking system is guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to mining dump truck vehicle braking technical field, more specifically, the utility model relates to a kind of hydraulic braking system of mining dump truck. BACKGROUND

[0002] Off-highway mining dump truck is important transport equipment in open-pit mine, water conservancy and hydropower and large-scale engineering mining operation, with the working characteristics of loading and unloading, heavy load, short transport distance, long continuous working time. The driving section of off-highway mining dump truck is mostly a simple repaired mixture of soil and gravel road, with common potholes, steep slopes and spirals, and needs to adapt to harsh working environments such as high temperature, high cold, mud, sand and wind. The driving environment of off-highway mining dump truck is poor, and the operation content is monotonous, which is easy to make the driver feel tired. The traditional off-highway mining dump truck is equipped with two to three drivers for each vehicle, and the vehicle is not rested to meet the large transportation requirements. As an important part of the whole vehicle, the braking system not only needs to adapt to various working environments, but also needs to meet the safety and reliability requirements.

[0003] Wide-body dump trucks with small tonnage are derived from heavy-duty trucks on highways, and use the common pneumatic drum brake system of power trucks, which has the advantages of large braking force, simple structure, low manufacturing cost and convenient maintenance. However, with the increasing load of dump trucks, the demand for braking force is also increasing. The traditional drum brake is limited by structure and is prone to overheating of the brake drum under heavy load and downhill working conditions, resulting in rapid decay of braking force. In severe cases, brake failure and tire burst may occur due to high temperature. In addition, the pneumatic drum brake system uses air as the power medium, which is compressed by a compressor and stored in a gas tank. The gas is then delivered to the brake chamber through various control valves to push the actuator to implement braking. In this process, air is subjected to suction, compression and storage, and the change in temperature will cause water vapor to condense and accumulate. If the drainage is not smooth, it will cause airway blockage and icing, seriously affecting the reliability and stability of the braking system. In addition, since the medium of pneumatic brake is air, the compression is relatively large, the response of the brake is slow, and the braking distance is also increased, which is not conducive to driving safety.

[0004] The traditional manned mine dump truck also has a hydraulic braking system. The hydraulic braking system of the manned mine dump truck comprises an oil tank, a hydraulic pump, a double-circuit liquid filling valve, an accumulator, a foot brake valve and a relay valve. The hydraulic pump sucks oil from the oil tank, and after passing through the double-circuit liquid filling valve, the hydraulic pump charges the accumulator with liquid, and at the same time, high-pressure oil enters the relay valve. When the driver steps on the foot brake valve, the control oil enters from the control oil port of the relay valve, and the output oil port of the relay valve outputs high-pressure oil to the brake. This braking system is suitable for a hydraulic caliper disc type service brake. The disadvantages of this system are as follows: once the hydraulic pump, the double-circuit liquid filling valve and the accumulator fail, it is difficult to achieve the braking purpose, the safety of the service brake is not high, the control precision of the braking force is low, and with the continuous development and maturity of the drive-by-wire chassis technology, the limitations of this system cannot meet the braking requirements of the unmanned mine dump truck.

[0005] Therefore, how to overcome the poor safety problem caused by the component failure of the hydraulic braking system of the traditional manned mine dump truck and the poor safety problem caused by the fatigue of the driver is a technical problem to be solved by the present application. SUMMARY

[0006] The utility model provides a mine dump truck hydraulic braking system, it is through setting up oil source subsystem and service brake subsystem, is equipped with a plurality of pressure sensor, element quantity is few, reliability is high, can realize mechanical and unmanned braking, improves braking response speed and reliability, guarantees the stable operation of braking system.

[0007] In order to realize these purposes and other advantages according to the utility model, a mine dump truck hydraulic braking system is provided, comprising:

[0008] The oil source subsystem comprises a hydraulic oil tank, a gear pump, a double-circuit liquid filling valve and an accumulator group connected in sequence, and the accumulator group comprises a front axle accumulator and a middle and rear axle accumulator connected in parallel.

[0009] The service brake subsystem comprises a front axle service brake group, a middle and rear axle service brake group and a double-circuit service brake valve group. The front axle service brake group comprises a front axle shuttle valve, a front axle relay valve and a front axle service brake connected in sequence, and the front axle relay valve is connected with the front axle accumulator. The middle and rear axle service brake group comprises a middle and rear axle shuttle valve, a middle and rear axle relay valve and a middle and rear axle service brake connected in sequence, and the middle and rear axle relay valve is connected with the middle and rear axle accumulator. The double-circuit service brake valve group comprises a double-circuit foot brake valve and a double-circuit electric proportional main brake valve arranged in parallel. The input ends of the double-circuit foot brake valve are connected with the front axle accumulator and the middle and rear axle accumulator respectively, the output ends of the double-circuit foot brake valve are connected with the front axle shuttle valve and the middle and rear axle shuttle valve respectively, the input end of the double-circuit electric proportional main brake valve is connected with the middle and rear axle accumulator, and the output end of the double-circuit electric proportional main brake valve is connected with the front axle shuttle valve and the middle and rear axle shuttle valve.

[0010] A plurality of pressure sensors are arranged on the hydraulic pipeline in the service brake subsystem to monitor the pressure of each part of the hydraulic brake system.

[0011] Preferably, the gear pump in the oil source subsystem is driven by an electric motor, and the gear pump is equipped with a high-pressure filter.

[0012] Preferably, the service brake valve group further comprises a double-circuit electric proportional backup brake valve, which is arranged in parallel with the double-circuit electric proportional main brake valve.

[0013] Preferably, the service brake valve group further comprises a pilot shuttle valve, the input ends of the double-circuit electric proportional main brake valve and the double-circuit electric proportional backup brake valve are connected with a rear axle accumulator, the output ends of the double-circuit electric proportional main brake valve and the double-circuit electric proportional backup brake valve are connected with the pilot shuttle valve, and the pilot shuttle valve is connected with the rear axle shuttle valve and the front axle shuttle valve.

[0014] Preferably, the system further comprises:

[0015] The parking brake subsystem comprises a parking brake, a parking brake accumulator, and a parking brake valve group, the parking brake valve group is connected with the double-circuit filling valve, and the parking brake valve group comprises a main check valve, a main electromagnetic reversing valve, and a pressure reducing valve connected in sequence, the parking brake accumulator is connected between the main check valve and the main electromagnetic reversing valve, and the flow direction of the main check valve is set to be from the double-circuit filling valve to the main electromagnetic reversing valve and the parking brake accumulator.

[0016] Preferably, a pressure switch is further installed on the hydraulic pipeline between the parking brake valve group and the parking brake.

[0017] Preferably, the parking brake valve group further comprises a backup electromagnetic reversing valve and a backup check valve, the backup electromagnetic reversing valve is connected in series between the main electromagnetic reversing valve and the pressure reducing valve, and the backup check valve is arranged in parallel with the pressure reducing valve; wherein the flow direction of the backup check valve is set to be from the parking brake to the backup electromagnetic reversing valve through the backup check valve.

[0018] Preferably, the plurality of pressure sensors are arranged in the service brake subsystem, including: one of the plurality of pressure sensors is arranged on a hydraulic pipeline between the dual-circuit filling valve and the front axle accumulator, one of the plurality of pressure sensors is arranged on a hydraulic pipeline between the dual-circuit filling valve and the rear axle accumulator, one of the plurality of pressure sensors is arranged on a hydraulic pipeline between the rear axle shuttle valve and the rear axle follow-up valve, one of the plurality of pressure sensors is arranged on a hydraulic pipeline between the front axle follow-up valve and the front axle service brake, and one of the plurality of pressure sensors is arranged on a hydraulic pipeline between the rear axle follow-up valve and the rear axle service brake.

[0019] The plurality of pressure sensors are arranged in the parking brake subsystem, including: one of the plurality of pressure sensors is arranged at an external oil port of the parking brake valve group, and one of the plurality of pressure sensors is arranged on a hydraulic pipeline between the parking brake valve group and the parking brake.

[0020] Preferably, the dual-circuit filling valve is connected to the hydraulic oil tank through a return hydraulic pipeline, the front axle follow-up valve is connected to the hydraulic oil tank through an oil return hydraulic pipeline, the rear axle follow-up valve is connected to the hydraulic oil tank through an oil return hydraulic pipeline, the dual-circuit foot brake valve is connected to the hydraulic oil tank through an oil return hydraulic pipeline, the dual-circuit electric proportional main brake valve and the dual-circuit electric proportional backup brake valve are connected to the hydraulic oil tank through an oil return hydraulic pipeline, and the parking brake valve group is connected to the hydraulic oil tank through an oil return hydraulic pipeline and an oil discharge hydraulic pipeline.

[0021] The mine dump truck comprises the mine dump truck hydraulic brake system.

[0022] The mine dump truck hydraulic brake system has at least the following beneficial effects:

[0023] Firstly, the front axle service brake and the rear axle service brake are two independent circuits, share the dual-circuit filling valve, the front axle service brake circuit is provided with the front axle accumulator, and the rear axle service brake circuit is provided with the rear axle accumulator, so that high-pressure oil stored in the accumulator can still complete multiple service brakes once any part of the oil source subsystem fails and cannot continuously supply oil to the brake system.

[0024] Secondly, the power medium is hydraulic oil, the hydraulic oil can be considered as incompressible, and the hydraulic pipeline is filled with hydraulic oil at all times, so that the dual-circuit foot brake valve in the manned mode and the dual-circuit electric proportional main brake valve in the unmanned mode are connected to the front axle service brake group and the rear axle service brake group, and brake instructions can be rapidly transmitted to the wheel service brake, the service brake has high sensitivity and fast response speed.

[0025] Third, the utility model disciously realize manned and unmanned braking system. When manned, the driver presses the brake pedal, and the relay valve is inputted control oil, and the braking purpose can be realized. When unmanned, the hydraulic braking system is inputted control oil to the relay valve through electromagnetic proportional brake valve, and the braking purpose can also be realized.

[0026] Fourth, the utility model disciously realize manned and unmanned braking system. When manned, the driver presses the brake pedal, and the relay valve is inputted control oil, and the braking purpose can be realized. When unmanned, the hydraulic braking system is inputted control oil to the relay valve through electromagnetic proportional brake valve, and the braking purpose can also be realized.

[0027] The other advantages, objects and features of the utility model will be embodied partly through the following description, and will be understood by the person skilled in the art through the research and practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of one technical scheme of the utility model. DETAILED DESCRIPTION

[0029] The utility model will be further explained in detail in connection with the drawings, so that the person skilled in the art can implement according to the description.

[0030] It should be understood that the terms such as "have", "contain" and "include" used in this paper do not exclude the presence or addition of one or more other elements or combinations thereof.

[0031] It should be noted that the experimental methods in the following embodiments are conventional methods, and the reagents and materials can be obtained from commercial channels unless otherwise specified. In the description of the utility model, it should be noted that unless otherwise explicitly specified and limited, the terms "mount", "connect", "set" should be understood broadly, for example, it can be fixedly connected, set, or detachably connected, set, or integrally connected, set. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances. The orientation or position relationship indicated by the terms "transverse", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and cannot be understood as indicating or implying that the device or element must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation on the utility model.

[0032] As shown in Figure 1 The utility model provides a kind of unmanned mine dump truck hydraulic braking system, comprising:

[0033] The oil source subsystem comprises a hydraulic oil tank 1, a gear pump, a double-circuit filling valve 4, an accumulator group connected in sequence, the double-circuit filling valve 4 is used for controlling the filling process of oil to the accumulator group, the accumulator group comprises a front axle accumulator 6.1 and a rear axle accumulator 6.2 connected in parallel, the hydraulic oil tank 1 is an independent hydraulic oil tank 1, an oil suction filter screen is arranged in the hydraulic oil tank 1, so that large-particle pollutants are prevented from entering the system, a large-diameter ball valve is arranged at the bottom of the hydraulic oil tank 1 and connected to an oil inlet of the gear pump, the gear pump delivers oil to the double-circuit filling valve 4 after the oil is sucked from the hydraulic oil tank 1, and the double-circuit filling valve 4 delivers hydraulic oil to the front axle accumulator 6.1 and the rear axle accumulator 6.2;

[0034] The service brake subsystem comprises a front axle service brake group, a rear axle service brake group and a double-circuit service brake valve group, the front axle service brake group and the rear axle service brake group are respectively responsible for service braking of the front axle and the rear axle, the front axle service brake group comprises a front axle shuttle valve 9.3, a front axle relay valve 11 and a front axle service brake 16 connected in sequence, the front axle relay valve 11 is connected with the front axle accumulator 6.1, the front axle relay valve 11 is also connected with the front axle service brake 16, the front axle shuttle valve 9.3 is used for selecting a suitable pressure oil source, the front axle relay valve 11 controls braking action of the front axle service brake 16 according to an input pressure signal, and when the front axle needs to be braked, oil in the front axle accumulator 6.1 is delivered to the front axle service brake 16 through the front axle relay valve 11 to realize braking; the rear axle service brake group comprises a rear axle shuttle valve 9.2, a rear axle relay valve 10 and a rear axle service brake 15 connected in sequence, the rear axle relay valve 10 is connected with the rear axle accumulator 6.2, the rear axle relay valve 10 is also connected with the rear axle service brake, the rear axle shuttle valve 9.2 is used for selecting a suitable pressure oil source, the rear axle relay valve 10 controls braking action of the rear axle service brake 15 according to an input pressure signal, and when the rear axle needs to be braked, oil in the rear axle accumulator 6.2 is delivered to the rear axle service brake 15 through the rear axle relay valve 10 to realize braking; preferably, control oil pressure received by the front axle relay valve 11 and the rear axle relay valve 10 is the same, but output pressure of the front axle relay valve 11 is slightly lower than that of the rear axle relay valve 10, so that front wheel slip during braking on a wet road surface is avoided, and steering ability is ensured while braking;

[0035] The double-circuit foot brake valve 7 is powered in response to a mechanical brake action, the input end of the double-circuit foot brake valve 7 is connected with the front axle accumulator 6.1 and the rear axle accumulator 6.2 respectively, the output end of the double-circuit foot brake valve 7 is connected with the front axle shuttle valve 9.3 and the rear axle shuttle valve 9.2 respectively, and the double-circuit foot brake valve 7 can be provided with an angle sensor; after the driver steps on the brake pedal, the vehicle control unit (VCU) detects the amplitude of the brake pedal stepping, powers the double-circuit foot brake valve 7, controls the oil to enter from the front axle relay valve 11 and the rear axle relay valve 10, outputs high-pressure oil from the front axle relay valve 11 and the rear axle relay valve 10 to the front axle service brake 16 and the rear axle service brake 15, and realizes mechanical braking.

[0036] The double-circuit electric proportional main brake valve 8.1 is powered in response to an unmanned driving brake instruction, the input end of the double-circuit electric proportional main brake valve 8.1 is connected with the rear axle accumulator 6.2, and high-pressure oil is real-time waiting at the input end, the output end of the double-circuit electric proportional main brake valve 8.1 is connected with the front axle shuttle valve 9.3 and the rear axle shuttle valve 9.2, controls the oil to enter from the front axle relay valve 11 and the rear axle relay valve 10, outputs high-pressure oil from the front axle relay valve 11 and the rear axle relay valve 10 to the front axle service brake 16 and the rear axle service brake 15, and realizes unmanned driving braking;

[0037] A plurality of pressure sensors are arranged on the hydraulic pipeline in the service brake subsystem to monitor the pressure of each part of the hydraulic brake system, specifically, a pressure sensor 5.1 is arranged on the hydraulic pipeline between the double-circuit filling valve 4 and the front axle accumulator 6.1, and a pressure sensor 5.2 is arranged on the hydraulic pipeline between the double-circuit filling valve 4 and the rear axle accumulator 6.2, the pressure sensors 5.1 and 5.2 monitor the system pressure in real time and feed back the pressure signal to the VCU, and the double-circuit filling valve 4 limits the working pressure of the system within a suitable range, specifically, when the VCU detects that the system pressure is lower than the set value, it sends a start command to charge the system; when the VCU detects that the system pressure reaches the set value, it sends a stop command, the motor 2 stops running, the accumulator maintains pressure, and the electric energy is saved. A pressure sensor 5.3 is arranged on the hydraulic pipeline between the rear axle shuttle valve 9.2 and the rear axle follow-up valve 10 to monitor the control oil pressure output by the double-circuit foot brake valve 7 to the rear axle follow-up valve 10 in real time; a pressure sensor 5.4 is arranged on the hydraulic pipeline between the front axle follow-up valve 11 and the front axle service brake 16, and a pressure sensor 5.5 is arranged on the hydraulic pipeline between the rear axle follow-up valve 10 and the rear axle service brake 15, the pressure sensors 5.4 and 5.5 monitor the pressure of the corresponding service brake in real time. These pressure sensors monitor the pressure of each part in real time and feed back the pressure signal to the vehicle controller (VCU). When the pressure of a certain part is abnormal, the vehicle controller (VCU) can respond in time to ensure the reliability and stability of the brake system. For example, if the pressure sensor between the front axle accumulator 6.1 and the double-circuit filling valve 4 detects that the pressure is too low, it may mean that there is a problem with the filling process, and the control system can control the gear pump to increase the working effort or check whether the double-circuit filling valve 4 is blocked.

[0038] In the above technical solution, by arranging the oil source subsystem and the service brake subsystem, a plurality of pressure sensors can monitor the pressure of each part of the brake system in real time to ensure stable operation of the brake system. The double-circuit service brake valve group can realize mechanical braking and unmanned braking, improving the adaptability and reliability of the brake system, effectively reducing the brake response time and reducing safety hazards.

[0039] In another technical solution, the gear pump in the oil source subsystem is driven by the motor 2, and the gear pump is equipped with a high-pressure filter 3. The gear pump is driven by the motor 2 to suck hydraulic oil from the hydraulic oil tank 1 when the motor 2 is running, and the oil outlet of the gear pump is equipped with a high-pressure filter 3 to improve the cleanliness of the system, preferably, a differential pressure alarm is installed on the high-pressure filter 3, when the filter element of the high-pressure filter 3 is too dirty, a significant pressure difference will occur between the inlet and outlet, at this time the differential pressure alarm can send a blockage alarm signal to the driver to remind replacing the filter element of the high-pressure filter 3.

[0040] In another technical solution, the service brake valve group further comprises a double-circuit electric proportional backup brake valve 8.2, which is arranged in parallel with the double-circuit electric proportional main brake valve 8.1, and is powered in response to an unmanned emergency service brake instruction, i.e., a service brake instruction when the double-circuit electric proportional main brake valve 8.1 fails. The double-circuit electric proportional backup brake valve 8.2 is a service brake function redundancy design. When the vehicle is in a normal unmanned driving state, the double-circuit electric proportional backup brake valve 8.2 is in a power-off state and does not participate in braking work. In the above technical solution, the double-circuit electric proportional backup brake valve 8.2 is added to provide a backup solution for the service brake. In the event of a main brake valve failure or an emergency, the backup brake valve can be used in time to ensure that the vehicle can be reliably braked, greatly improving the safety of the service brake and avoiding dangerous situations caused by brake failure.

[0041] In another technical solution, the service brake valve group further comprises: a pilot shuttle valve 9.1, the input ends of the double-circuit electric proportional main brake valve 8.1 and the double-circuit electric proportional standby brake valve 8.2 are connected with the middle and rear axle accumulator 6.2, and high-pressure oil is in real time at the two input ends, the output ends of the double-circuit electric proportional main brake valve 8.1 and the double-circuit electric proportional standby brake valve 8.2 are connected with the pilot shuttle valve 9.1, and the pilot shuttle valve 9.1 is connected with the middle and rear axle shuttle valve 9.2 and the front axle shuttle valve 9.3. When an emergency occurs, such as a failure of the double-circuit electric proportional main brake valve 8.1, an unmanned emergency service brake command is issued, at this time, the double-circuit electric proportional standby brake valve 8.2 is powered on, and the pressure oil in the middle and rear axle accumulator 6.2 reaches the pilot shuttle valve 9.1 through the double-circuit electric proportional standby brake valve 8.2. When the double-circuit electric proportional main brake valve 8.1 is powered on, the high-pressure oil enters the 1 port of the pilot shuttle valve 9.1 through the double-circuit electric proportional main brake valve 8.1, and when the double-circuit electric proportional standby brake valve 8.2 is powered on, the high-pressure oil enters the 2 port of the pilot shuttle valve 9.1 through the double-circuit electric proportional standby brake valve 8.2. After the two high-pressure oils are automatically screened by the pilot shuttle valve 9.1, the higher pressure oil flows out from the 3 port of the pilot shuttle valve 9.1 and simultaneously enters the 2 ports of the front axle shuttle valve 9.3 and the middle and rear axle shuttle valve 9.2, and the front axle shuttle valve 9.3 and the middle and rear axle shuttle valve 9.2 again screen the pressures of the 1 port and the 2 port respectively, output the higher pressure oil, and output the higher pressure oil from the 3 ports of the front axle shuttle valve 9.3 and the middle and rear axle shuttle valve 9.2 respectively, and through the hydraulic pipeline, the higher pressure oil enters the front axle follow-up valve 11 and the middle and rear axle follow-up valve 10 respectively, and the front axle follow-up valve 11 and the middle and rear axle follow-up valve 10 output high-pressure oil and enter the front axle service brake 16 and the middle and rear axle service brake 15 respectively to implement braking. In the double-circuit service brake valve group, the double-circuit electric proportional main brake valve 8.1 and the double-circuit electric proportional standby brake valve 8.2 are installed in parallel, which are used to implement service braking in the unmanned driving mode, the functions of the two electromagnetic proportional valves are different, in order to improve the safety and reliability of the unmanned braking system, the two electromagnetic proportional pressure reducing valves are installed in parallel, one is used as a main brake valve and the other is used as a standby brake valve, and the functions of the manned driving mode and the unmanned driving mode coexist.

[0042] In another technical solution, it further comprises:

[0043] The parking brake subsystem includes a parking brake 14, a parking brake accumulator 15, a parking brake valve group 12, an inlet port P of the parking brake valve group 12 being connected to a bypass port SW of the double-circuit filling valve 4 through a hydraulic pipeline, an external oil port of the parking brake valve group 12 being connected to the parking brake accumulator 15 through a hydraulic pipeline, and oil being able to enter the parking brake valve group 12 through the double-circuit filling valve 4 when the oil source subsystem is working. Specifically, the parking brake valve group 12 includes a main one-way valve 12.1, a main electromagnetic reversing valve 12.2 and a pressure reducing valve 12.4 connected in sequence, the main one-way valve 12.1 being installed inside the inlet port P of the parking brake valve group 12 to prevent hydraulic oil backflow and ensure that the parking brake accumulator 15 can normally store pressure. The pressure reducing valve 12.4 functions to adjust the pressure to a suitable range to avoid damage to the parking brake 14 caused by excessively high pressure. The parking brake accumulator 15 is connected between the main one-way valve 12.1 and the main electromagnetic reversing valve 12.2, and high-pressure oil waits at the main electromagnetic reversing valve 12.2 to effectively ensure that the pressure is continuous and stable when the parking brake is released, the main electromagnetic reversing valve 12.2 being powered in response to a parking brake instruction, and the flow direction of the main one-way valve 12.1 being set such that oil flows from the double-circuit filling valve 4 to the main electromagnetic reversing valve 12.2 and the parking brake accumulator 15. When the vehicle needs to be parked, the vehicle controller (VCU) sends a parking brake instruction, and the main electromagnetic reversing valve 12.2 is powered. When the main electromagnetic reversing valve 12.2 is powered, high-pressure oil is allowed to pass, is reduced in pressure by the pressure reducing valve 12.4, reaches a set pressure required for parking brake release, and finally enters the parking brake 14 through a hydraulic pipeline to push the piston to retract and release the parking brake.

[0044] In the above technical solution, the bypass port of the double-circuit filling valve 4 is connected to the inlet port of the parking brake valve group 12, and the flow direction of oil is controlled by an insertion type electromagnetic valve installed on the parking brake valve; when the main electromagnetic reversing valve 12.2 is powered, high-pressure oil passes through the main electromagnetic reversing valve 12.2, then passes through an insertion type pressure reducing valve 12.4, and finally enters the parking brake 14 through a hydraulic pipeline to push the piston of the parking brake 14 to retract and release the parking brake. The parking brake subsystem can realize reliable parking brake and can monitor the system state in real time, thereby improving the stability and safety of the parking brake. The pressure sensor and the pressure switch 13 can monitor the pressure of the parking brake in real time to ensure the reliability of the parking brake.

[0045] In another technical solution, a pressure switch 13 is further installed on the hydraulic pipeline between the parking brake valve group 12 and the parking brake 14, and when the pressure switch 13 monitors that the pressure oil entering the parking brake 14 reaches a set value, the internal circuit of the pressure switch 13 is connected, a signal is sent to the vehicle VCU, and the parking brake light on the instrument in the cockpit is turned off.

[0046] In another technical solution, the parking brake valve group 12 further comprises a backup electromagnetic directional valve 12.3 and a backup check valve 12.5. The backup electromagnetic directional valve 12.3 is a parking brake function redundancy design. When the main electromagnetic directional valve 12.2 fails to safely park the parking brake 14, the backup electromagnetic directional valve 12.3 is powered on, and the high-pressure oil in the parking brake 14 returns through the backup electromagnetic directional valve 12.3. The backup electromagnetic directional valve 12.3 is connected in series between the main electromagnetic directional valve 12.2 and the pressure reducing valve 12.4. The backup electromagnetic directional valve 12.3 is powered on in response to an emergency parking brake command, i.e., a parking brake command when the main electromagnetic directional valve 12.2 fails. The backup check valve 12.5 is connected in parallel with the pressure reducing valve 12.4. The flow direction of the backup check valve 12.5 is set so that the oil flows from the parking brake 14 to the backup electromagnetic directional valve 12.3 through the backup check valve 12.5. In a normal parking brake process, the backup electromagnetic directional valve 12.3 is in a power-off state. However, when an emergency situation occurs, such as a failure of the main electromagnetic directional valve 12.2, the vehicle controller (VCU) will issue an emergency parking brake command, and the backup electromagnetic directional valve 12.3 will be powered on.

[0047] In the above technical solution, the addition of the backup electromagnetic directional valve 12.3 and the backup check valve 12.5 provides an emergency braking function for the parking brake system. In an emergency situation, parking brake can be quickly achieved to avoid safety accidents caused by parking brake system failure.

[0048] In another technical solution, a pressure sensor 5.6 is arranged at the external oil port of the parking brake valve group 12 to monitor the pressure of the parking brake accumulator 15 in real time. A pressure sensor 5.7 is arranged on the hydraulic pipeline between the parking brake valve group 12 and the parking brake 14 to monitor the parking brake release pressure in real time.

[0049] In another technical solution, the double-circuit liquid filling valve 4 is connected to the hydraulic oil tank 1 through a backflow hydraulic pipeline, so that excess oil can flow back to the hydraulic oil tank 1 during the liquid filling process, ensuring the stability of the system pressure. The front axle relay valve 11 is connected to the hydraulic oil tank 1 through an oil return hydraulic pipeline, the middle and rear axle relay valve 10 is connected to the hydraulic oil tank 1 through an oil return hydraulic pipeline, the double-circuit foot brake valve 7 is connected to the hydraulic oil tank 1 through an oil return hydraulic pipeline, and the double-circuit electric proportional main brake valve 8.1 and the double-circuit electric proportional standby brake valve 8.2 are connected to the hydraulic oil tank 1 through an oil return hydraulic pipeline. During the release of the service brake, the oil in these valves can flow back to the hydraulic oil tank 1 through the oil return hydraulic pipeline. For example, when the driver releases the brake pedal or the autonomous driving system cancels the brake instruction, the oil in the front axle relay valve 11 and the middle and rear axle relay valve 10 will flow back to the hydraulic oil tank 1 through the oil return hydraulic pipeline, causing the brake to release and the vehicle to resume normal driving. The parking brake valve group 12 is connected to the hydraulic oil tank 1 through an oil return hydraulic pipeline, and the oil in the parking brake valve group 12 can flow back to the hydraulic oil tank 1 when the parking brake is released. The parking brake valve group 12 is also connected to the hydraulic oil tank 1 through a drain oil hydraulic pipeline, which functions to quickly drain the oil in the parking brake valve group 12 when necessary.

[0050] In the above technical solution, the arrangement of multiple backflow and drain oil hydraulic pipelines ensures the normal backflow and drainage of hydraulic oil in the hydraulic system, maintains the stability of the hydraulic system pressure, and improves the performance and reliability of the brake system.

[0051] The autonomous mine dump truck comprises the autonomous mine dump truck hydraulic brake system.

[0052] During driving, whether the driver performs mechanical brake operation or the autonomous driving system issues a brake instruction, the brake system can respond quickly. The design of the double-circuit service brake valve group allows flexible switching and cooperation between mechanical brake and autonomous driving brake, improving the adaptability and reliability of the brake. In case of emergency, the double-circuit electric proportional standby brake valve 8.2 and the standby electromagnetic reversing valve 12.3 and other standby mechanisms can quickly work, providing additional brake protection for the vehicle. The reasonable arrangement of the backflow and drain oil hydraulic pipelines ensures the stability of the hydraulic system pressure and the normal circulation of the oil, prolonging the service life of the brake system. By applying the optimized brake system to the autonomous mine dump truck, the braking performance and safety of the entire vehicle are improved, meeting the operational requirements in complex mine environments.

[0053] In the above technical solution, the optimized brake system is applied to the autonomous mine dump truck, improving the braking response speed, reliability, and precise control ability of the entire vehicle, meeting the safe driving requirements of the autonomous mine dump truck in complex mine environments.

[0054] Specifically, as shown in Figure 1 P1 and P2 ports of the double-circuit foot brake valve 7 are connected to the front axle accumulator 6.1 and the rear axle accumulator 6.2 through hydraulic pipelines respectively, A1 and A2 ports of the double-circuit foot brake valve 7 are respectively installed with 1 ports of the front axle shuttle valve 9.3 and the rear axle shuttle valve 9.2, and the T port of the double-circuit foot brake valve 7 is connected to the oil return port of the hydraulic oil tank 1 through a hydraulic pipeline.

[0055] The P ports of the double-circuit electric proportional main brake valve 8.1 and the double-circuit electric proportional standby brake valve 8.2 are connected to the rear axle accumulator 6.2 through hydraulic pipelines and three-way joints respectively, high-pressure oil enters the 1 port and the 2 port of the pilot shuttle valve 9.1 after passing through the double-circuit electric proportional main brake valve 8.1 and the double-circuit electric proportional standby brake valve 8.2 respectively, and the pressure of the two high-pressure oils is automatically screened through the pilot shuttle valve 9.1, the higher pressure oil flows out from the 3 port of the pilot shuttle valve 9.1 and enters the 2 ports of the front axle shuttle valve 9.3 and the rear axle shuttle valve 9.2, and the 1 ports of the front axle shuttle valve 9.3 and the rear axle shuttle valve 9.2 are connected to the A1 and A2 ports of the double-circuit foot brake valve 7 respectively, the front axle shuttle valve 9.3 and the rear axle shuttle valve 9.2 screen the pressure of the 1 port and the 2 port again, output the higher pressure oil, and the higher pressure oil is output from the 3 ports of the front axle shuttle valve 9.3 and the rear axle shuttle valve 9.2 respectively, enters the PP port of the rear axle follow-up valve 10 and the PP port of the front axle follow-up valve 11 through hydraulic pipelines respectively, and outputs high-pressure oil to the front axle service brake 16 and the rear axle service brake 15 through the A port of the rear axle follow-up valve 10 and the A port of the front axle follow-up valve 11, the P port of the rear axle follow-up valve 10 is connected to the rear axle accumulator 6.2, and the P port of the front axle follow-up valve 11 is connected to the front axle accumulator 6.1.

[0056] The hydraulic brake system oil circuit composition of the utility model is specifically:

[0057] The oil source subsystem composition is: hydraulic oil tank 1-gear pump-high pressure filter 3-double circuit liquid filling valve 4-front axle accumulator 6.1+rear axle accumulator 6.2, and the liquid filling is automatically completed in the process, so that the brake system pressure is maintained in the set range.

[0058] The hydraulic brake system of the utility model can realize the following actions, and the front axle service brake, the rear axle service brake, the emergency service brake, the parking brake, and the emergency parking brake oil circuit composition are specifically:

[0059] (1) Front axle service brake:

[0060] ① Manual driving mode: double-circuit foot brake valve 7-front axle shuttle valve 9.3-front axle follow-up valve 11-front axle service brake 16, the process is purely mechanical, and the safety and reliability are high;

[0061] (2) Front axle service brake:

[0062] (2) Rear axle service brake:

[0063] (1) Manual service brake:

[0064] (2) Autonomous service brake:

[0065] (3) Emergency service brake:

[0066] (1) Manual service brake:

[0067] (2) Autonomous service brake:

[0068] (3) Emergency service brake:

[0069] (4) Parking brake:

[0070] (1) Manual service brake:

[0071] (5) Emergency parking brake:

[0072] (1) Manual service brake:

[0073] The number of devices and the scale of processing described herein are used to simplify the description of the present application. The application, modification and change of the present application are obvious to those skilled in the art.

[0074] Although the embodiments of the present application have been disclosed as above, it is not limited to the application listed in the specification and the embodiments, and it can be applied to various fields suitable for the present application. For those skilled in the art, other modifications can be easily realized, and therefore the present application is not limited to specific details and the figures shown and described herein.

Claims

1. Hydraulic braking system for a mine dump truck, characterized in that Comprise: The oil source subsystem comprises a hydraulic oil tank, a gear pump, a double circuit filling valve, an accumulator group connected in sequence, the accumulator group comprises a front axle accumulator, a rear axle accumulator connected in parallel; The service brake subsystem comprises a front axle service brake group, a rear axle service brake group, a double circuit service brake valve group, the front axle service brake group comprises a front axle shuttle valve, a front axle relay valve, a front axle service brake connected in sequence, the front axle relay valve is connected with the front axle accumulator; the rear axle service brake group comprises a rear axle shuttle valve, a rear axle relay valve, a rear axle service brake connected in sequence, the rear axle relay valve is connected with the rear axle accumulator; the double circuit service brake valve group comprises a double circuit foot brake valve, a double circuit electric proportional main brake valve connected in parallel; the input end of the double circuit foot brake valve is connected with the front axle accumulator and the rear axle accumulator respectively, the output end of the double circuit foot brake valve is connected with the front axle shuttle valve and the rear axle shuttle valve respectively; the input end of the double circuit electric proportional main brake valve is connected with the rear axle accumulator, the output end of the double circuit electric proportional main brake valve is connected with the front axle shuttle valve and the rear axle shuttle valve. A plurality of pressure sensors are arranged on the hydraulic pipeline in the service brake subsystem for monitoring the pressure of each part of the hydraulic brake system.

2. The hydraulic braking system for a mining dump truck of claim 1, wherein, The gear pump in the oil source subsystem is driven by a motor, and the gear pump is provided with a high pressure filter.

3. The hydraulic braking system for a mining dump truck of claim 1, wherein, The service brake valve group further comprises a double circuit electric proportional standby brake valve connected in parallel with the double circuit electric proportional main brake valve.

4. The hydraulic braking system for a mining dump truck of claim 3, wherein, The service brake valve group further comprises a pilot shuttle valve, the input end of the double circuit electric proportional main brake valve and the double circuit electric proportional standby brake valve is connected with the rear axle accumulator, the output end of the double circuit electric proportional main brake valve and the double circuit electric proportional standby brake valve is connected with the pilot shuttle valve, the pilot shuttle valve is connected with the rear axle shuttle valve and the front axle shuttle valve.

5. A hydraulic braking system for a mining dump truck as claimed in any one of claims 1 to 4, characterised in that, Further comprise: The parking brake subsystem comprises a parking brake, a parking brake accumulator, a parking brake valve group, the parking brake valve group is connected with the double circuit filling valve, the parking brake valve group comprises a main check valve, a main electromagnetic reversing valve, a pressure reducing valve connected in sequence, the parking brake accumulator is connected between the main check valve and the main electromagnetic reversing valve, the flow direction of the main check valve is set as oil flowing from the double circuit filling valve to the main electromagnetic reversing valve and the parking brake accumulator.

6. The hydraulic braking system for a mining dump truck of claim 5, wherein, A pressure switch is further installed on the hydraulic pipeline between the parking brake valve group and the parking brake.

7. The hydraulic braking system for a mining dump truck of claim 6, wherein, The parking brake valve group further comprises a standby electromagnetic reversing valve and a standby check valve, the standby electromagnetic reversing valve is connected in series between the main electromagnetic reversing valve and the pressure reducing valve, the standby check valve is connected in parallel with the pressure reducing valve; wherein, the flow direction of the standby check valve is set as oil flowing from the parking brake to the standby electromagnetic reversing valve through the standby check valve.

8. The hydraulic braking system of a mining dump truck as claimed in claim 7, wherein, The multiple pressure sensors are arranged in the service brake subsystem, including: one of the multiple pressure sensors is arranged on the hydraulic pipeline between the double-circuit filling valve and the front axle accumulator, one of the multiple pressure sensors is arranged on the hydraulic pipeline between the double-circuit filling valve and the rear axle accumulator, one of the multiple pressure sensors is arranged on the hydraulic pipeline between the rear axle shuttle valve and the rear axle follow-up valve, one of the multiple pressure sensors is arranged on the hydraulic pipeline between the front axle follow-up valve and the front axle service brake, and one of the multiple pressure sensors is arranged on the hydraulic pipeline between the rear axle follow-up valve and the rear axle service brake; The multiple pressure sensors are arranged in the parking brake subsystem, including: one of the multiple pressure sensors is arranged at the external oil port of the parking brake valve group, and one of the multiple pressure sensors is arranged on the hydraulic pipeline between the parking brake valve group and the parking brake.

9. The hydraulic braking system for a mining dump truck of claim 7, wherein, The double-circuit filling valve is connected to the hydraulic oil tank through a return hydraulic pipeline, the front axle follow-up valve is connected to the hydraulic oil tank through an oil return hydraulic pipeline, the rear axle follow-up valve is connected to the hydraulic oil tank through an oil return hydraulic pipeline, the double-circuit foot brake valve is connected to the hydraulic oil tank through an oil return hydraulic pipeline, the double-circuit electric proportional main brake valve and the double-circuit electric proportional standby brake valve are connected to the hydraulic oil tank through an oil return hydraulic pipeline, the parking brake valve group is connected to the hydraulic oil tank through an oil return hydraulic pipeline, and the parking brake valve group is further connected to the hydraulic oil tank through an oil discharge hydraulic pipeline.

10. A mine dump truck, characterized in that The hydraulic brake system of the mine dump truck comprises the hydraulic brake system of the mine dump truck according to any one of claims 1-9.

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