Hydraulic systems and dump trucks

Abstract

This utility model provides a hydraulic system and a dump truck. The hydraulic system includes a hydraulic oil tank, a variable displacement pump, a steering valve assembly, a steering mechanism, a brake valve assembly, a parking brake, a lifting mechanism, an emergency pump, and an emergency valve assembly. The variable displacement pump and the emergency pump are connected to the hydraulic oil tank. The steering valve assembly is connected to the variable displacement pump and supplies oil to the steering mechanism. The lifting mechanism is connected to the steering valve assembly via a first oil circuit. The brake valve assembly is connected to the parking brake via a second oil circuit. The emergency valve assembly is connected to the emergency pump, and is connected to the steering valve assembly via a first emergency line and to the brake valve assembly via a second emergency line. The oil passing through the emergency pump is defined as emergency oil. The emergency oil, via the emergency valve assembly, can be used for emergency steering, emergency lifting, and releasing the parking brake. This utility model's hydraulic system can solve the problem of dump trucks being unable to work normally under fault conditions and the need for relocation and repair, improving relocation and repair capabilities.

Description

Technical Field

[0001] This utility model relates to the field of engineering machinery technology, and in particular to a hydraulic system and a dump truck. Background Technology

[0002] Currently, mining dump trucks are mostly used on roads in open-pit mines and large-scale civil engineering sites, where road conditions are extremely poor. To transport minerals, mining dump trucks generally employ large tonnage loads. Due to the weight and heavy load of the mining dump trucks, and the large size and weight of the vehicle components, on-site repairs are difficult. If a vehicle breaks down and loses power, even with a dedicated trailer, it is difficult to relocate it for repairs, causing significant difficulties for maintenance work and consequently affecting production efficiency.

[0003] In existing technologies, although mining dump trucks have energy storage devices, when a mining dump truck malfunctions and loses power, the energy storage device only has a brief emergency steering and braking function. It does not have the function of long-term control of emergency braking, steering, and lifting. Especially during transportation or unloading, vehicles without emergency functions will seriously affect road transportation and maintainability. Utility Model Content

[0004] In view of this, the purpose of this utility model is to provide a hydraulic system that can solve the problem of dump trucks being unable to work normally and being relocated for maintenance under fault conditions in the prior art, thereby improving the relocation and maintenance capability.

[0005] This utility model provides a hydraulic system, including a hydraulic oil tank, an engine, a variable displacement pump, a steering valve assembly, a steering mechanism, a brake valve assembly, a parking brake, a lifting mechanism, an emergency pump, and an emergency valve assembly. The variable displacement pump and the emergency pump are respectively connected to the hydraulic oil tank. The engine is connected to the variable displacement pump to drive its rotation. The steering valve assembly is connected to the variable displacement pump and supplies oil to the steering mechanism to control steering. The lifting mechanism is connected to the steering valve assembly via a first oil circuit. The brake valve assembly is connected to the parking brake via a second oil circuit. The emergency valve assembly is connected to the emergency pump, and is connected to the steering valve assembly via a first emergency line and to the brake valve assembly via a second emergency line. The oil passing through the emergency pump is defined as emergency oil. The emergency oil, via the emergency valve assembly, can be used for emergency steering, emergency lifting, and releasing the parking brake.

[0006] In one embodiment, the emergency valve assembly includes a first oil inlet, a first reversing valve, a first oil outlet, and a second oil outlet. When emergency steering or emergency lifting is required, the first oil inlet is connected to the first oil outlet, and the first oil inlet is disconnected from the second oil outlet. Emergency oil from the emergency pump enters the emergency valve assembly through the first oil inlet and flows from the first oil outlet to the first emergency pipeline. The emergency oil is supplied to the steering valve assembly through the first emergency pipeline, enabling the steering valve assembly to supply oil to the steering mechanism for emergency steering. When emergency steering is not required, the emergency oil is supplied to the lifting mechanism for emergency lifting through the first emergency pipeline, the steering valve assembly, and the first oil circuit.

[0007] In one embodiment, the emergency valve assembly is provided with a first oil inlet, a first reversing valve, and a second oil outlet. When it is necessary to release the parking brake, the first reversing valve connects the first oil inlet and the second oil outlet. The emergency oil from the emergency pump flows through the first oil inlet, the first reversing valve, and the second oil outlet to the second emergency pipeline. The second emergency pipeline supplies oil to the brake valve assembly, and the brake valve assembly supplies oil to the parking brake through the second oil circuit to release the parking brake.

[0008] In one embodiment, the emergency valve assembly further includes a pressure reducing valve connected between the first oil inlet and the first directional valve, the pressure reducing valve being used to reduce the pressure of the emergency oil flowing to the second emergency pipeline.

[0009] In one embodiment, the emergency valve assembly includes a first check valve connected between the first oil inlet and the first oil outlet, wherein emergency oil from the first oil inlet flows to the first oil outlet via the first check valve.

[0010] In one embodiment, the hydraulic system further includes an electric motor connected to the emergency pump, which drives the emergency pump to rotate in order to supply oil to the emergency valve assembly.

[0011] In one embodiment, the hydraulic system includes a flow amplification valve assembly connected between the steering valve assembly and the steering mechanism. The flow amplification valve assembly includes a priority valve. When emergency oil from the steering valve assembly flows to the priority valve, the priority valve communicates with the steering mechanism when the steering mechanism needs to turn, and the emergency oil flows to the steering mechanism via the priority valve.

[0012] In one embodiment, the steering valve assembly includes a first solenoid valve and a sequence valve. When the lifting mechanism needs to lift, the first solenoid valve is energized, the sequence valve connects the priority valve to the first oil circuit, and the emergency oil flows to the lifting mechanism after passing through the priority valve, the sequence valve, and the first oil circuit.

[0013] In one embodiment, the hydraulic system further includes an emergency brake release button, which is electrically connected to the first directional valve and is used to switch the operating position of the first directional valve; the first directional valve can be manually switched.

[0014] In one embodiment, the brake valve assembly includes a shuttle valve connected to the second oil circuit. When the engine malfunctions and the parking brake needs to be released, the emergency oil flows to the parking brake via the second emergency line, the shuttle valve, and the second oil circuit.

[0015] In one embodiment, the hydraulic system further includes a double gear pump, which is coaxially connected to the variable pump. One end of the double gear pump is connected to the hydraulic oil tank, and the other end of the double gear pump is connected to the lifting mechanism to supply oil.

[0016] This utility model also relates to a dump truck, including the aforementioned hydraulic system.

[0017] The hydraulic system of this utility model is equipped with an emergency pump and an emergency valve group. The emergency valve group is connected to the steering valve group through a first emergency pipeline. When the engine fails, the emergency pump and the emergency valve group work together to quickly supply emergency oil to the steering mechanism or lifting mechanism to realize emergency steering or emergency lifting functions. The emergency valve group is connected to the brake valve group through a second emergency pipeline. When the engine fails and needs to be moved for repair, emergency oil can be quickly supplied to the parking brake to release the parking brake and improve the relocation efficiency of the dump truck. The emergency pump and emergency valve group of this hydraulic system are not only easy to install and simple to use, but also low in cost. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the hydraulic system of this utility model.

[0020] Figure 2This is a schematic diagram of the steering valve assembly of this utility model.

[0021] Figure 3 This is a schematic diagram of the brake valve assembly of this utility model.

[0022] Figure 4 This is a schematic diagram of the emergency valve assembly of this utility model.

[0023] Figure 5 This is a schematic diagram of the flow amplification valve assembly of this utility model.

[0024] Reference numerals: First oil inlet - P1; First oil outlet - ES; Second oil outlet - EB; Hydraulic oil tank - 11; Engine - 12; Variable displacement pump - 13; Steering valve assembly - 14; First solenoid valve - 141; Sequence valve - 142; Brake valve assembly - 15; Shuttle valve - 151; Parking solenoid valve - 152; Flow amplification valve assembly - 16; Priority valve - 161; Steering mechanism - 171; Parking brake - 172; Service brake - 173; Lifting mechanism - 174; Steering accumulator - 175; Brake accumulator - 176; First filter - 177; High pressure filter - 178; Return oil filter element - 179; Foot valve - 181; Double gear pump - 182; First emergency line - 191; Second emergency line - 192; First oil line - 193; Second oil line - 194; First branch line - 195; Second branch line - 196; Third branch line - 197; Emergency pump - 21; Emergency valve assembly - 22; First directional valve - 221; Pressure reducing valve - 222; First check valve - 223; First on / off valve - 224; First relief valve - 225; Motor - 23. Detailed Implementation

[0025] The specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of this utility model. Based on the description of this utility model, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this utility model.

[0026] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0027] The terms “upper,” “lower,” “left,” “right,” “front,” “back,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of description and simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0028] The terms “first,” “second,” “third,” etc., are used merely to distinguish elements with similar properties, not to indicate or imply relative importance or a specific order.

[0029] The terms “include,” “comprising,” or any other variation thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0030] like Figures 1 to 5 As shown, the dump truck includes a hydraulic system with an emergency function. The hydraulic system includes a hydraulic oil tank 11, an engine 12, a variable displacement pump 13, a steering valve assembly 14, a steering mechanism 171, a brake valve assembly 15, a parking brake 172, a lifting mechanism 174, an emergency pump 21, and an emergency valve assembly 22. The variable displacement pump 13 and the emergency pump 21 are respectively connected to the hydraulic oil tank 11. The engine 12 is connected to the variable displacement pump 13 to drive its rotation. The steering valve assembly 14 is connected to the variable displacement pump 13 and is used to provide steering... Mechanism 171 supplies oil to control steering; the hydraulic system includes a flow amplification valve assembly 15, which is connected between the steering valve assembly 14 and the steering mechanism 171. The flow amplification valve assembly 15 includes a priority valve 161, which regulates the working state of the hydraulic system by controlling the priority channel and priority flow. Specifically, when the hydraulic system needs to control the steering mechanism 171 for steering, the priority valve 161 connects to the steering mechanism 171, prioritizing the steering function before satisfying other functions. The steering mechanism 171 and the lifting mechanism 174 are drive cylinders. It is understood that in this embodiment, the valve assemblies and valves are connected via pipelines.

[0031] like Figure 1 and Figure 2As shown, the hydraulic system also includes a steering accumulator 175, which is connected to the steering valve assembly 14. The steering valve assembly 14 includes a first branch 195, a second branch 196, and a third branch 197. The steering accumulator 175 is connected to the first branch 195, the flow amplification valve assembly 15 is connected to the second branch 196, and the brake valve assembly 15 is connected to the third branch 197. Therefore, when the engine 12 starts, hydraulic oil flows simultaneously to the steering accumulator 175, the steering valve assembly 14, and the brake valve assembly 15. The hydraulic system also includes a brake accumulator 176, which is connected to the brake valve assembly 15 and is connected to the third branch 197, allowing hydraulic oil to flow to the brake accumulator 176 via the third branch 197. Steering energy accumulator 175 can provide a short-term emergency function, but it can only meet the needs of turning the steering wheel one round and one round. Brake energy accumulator 176 can provide a short-term emergency function, and can meet the needs of foot valve 1815-8 braking actions. Therefore, steering energy accumulator 175 and brake energy accumulator 176 can only meet short-term emergency needs and cannot meet the needs of relocation and maintenance.

[0032] Preferably, the lifting mechanism 174 is connected to the steering valve assembly 14 via the first oil circuit 193; the brake valve assembly 15 is connected to the parking brake 172 via the second oil circuit 194; the brake valve assembly 15 includes a parking solenoid valve 152, and when the parking solenoid valve 152 is energized, hydraulic oil enters the parking brake 172 through the parking solenoid valve 152 to release the parking brake.

[0033] The oil in the hydraulic oil tank 11 that passes through the variable pump 13 or the double gear pump 182 is defined as hydraulic oil;

[0034] When the engine 12 is in normal working condition, the working principle of the steering mechanism 171 is as follows: After the engine 12 is started, the engine 12 drives the variable pump 13 to rotate. The hydraulic oil enters the steering valve group 14 through the variable pump 13. The hydraulic oil fills the steering accumulator 175 through the first branch 195. When the driver turns the steering wheel, the priority valve 161 switches to the right position, that is, the priority valve 161 connects the second branch 196 with the steering mechanism 171. The oil enters the steering mechanism 171 through the flow amplification valve group 15 to achieve steering.

[0035] When the engine 12 is in normal working condition, the braking principle is as follows: Braking includes parking brake and service brake. After starting the engine 12, the engine 12 drives the variable pump 13 to rotate. Hydraulic oil enters the steering valve group 14 through the variable pump 13. The hydraulic oil fills the brake accumulator 176 through the third branch 197. When the driver presses the parking brake release button in the cab, the parking solenoid valve 152 is energized, and hydraulic oil enters the parking brake 172 to release the parking brake, ensuring that the vehicle can drive. During driving, if it is necessary to decelerate, the driver can step on the brake pedal. Hydraulic oil enters the service brake 173 through the foot valve 181, so that the vehicle decelerates. It can be understood that the foot valve 181 is located in the brake valve group 15.

[0036] When the engine 12 is in normal working condition, after starting the engine 12, the hydraulic oil enters the first branch 195, the second branch 196 and the third branch 197 simultaneously through the variable pump 13. The steering accumulator 175 and the brake accumulator 176 are filled with oil at the same time. When there is no steering or lifting or other operation, the hydraulic oil in the second branch 196 finally returns to the hydraulic oil tank 11.

[0037] Preferably, the hydraulic system further includes a double gear pump 182 and a high-pressure filter 178. The double gear pump 182 is coaxially connected to the variable pump 13. One end of the double gear pump 182 is connected to the hydraulic oil tank 11, and the other end is connected to the lifting mechanism 174. The high-pressure filter 178 is connected between the double gear pump 182 and the lifting mechanism 174 to filter impurities. The steering valve assembly 14 also includes a first solenoid valve 141 and a sequence valve 142. When the lifting mechanism 174 needs to lift, the first solenoid valve 141 is energized, and the sequence valve 142 connects the priority valve 161 and the first oil circuit 193.

[0038] Preferably, the hydraulic system further includes a first filter 177, which is connected between the variable pump 13 and the steering valve assembly 14, and is used to filter impurities in the hydraulic oil.

[0039] When the engine 12 is in normal working condition, the lifting mechanism 174 works as follows: When the driver pushes the handle to the lifting position in the cab, the lifting positions are lifting, holding, and floating. At this time, two parts of hydraulic oil flow into the lifting mechanism 174. One part is the hydraulic oil from the variable pump 13. When there is no steering and the first solenoid valve 141 is energized, the hydraulic oil enters the lifting mechanism 174 from the EF2 port of the steering valve group 14 via the E port. The other part enters the lifting mechanism 174 through the double gear pump 182 and the high-pressure filter 178, achieving a large-flow lifting. When the driver pushes the handle to the forced-down position, the flow merging function is not required. Therefore, the first solenoid valve 141 is not energized, and only the double gear pump 182 outputs hydraulic oil into the lifting mechanism 174 to achieve the lowering function.

[0040] like Figure 1 As shown, the hydraulic system also includes a motor 23, which is electrically connected to the emergency pump 21. The emergency valve assembly 22 is connected to the emergency pump 21. The motor 23 can drive the emergency pump 21 to rotate to supply oil to the emergency valve assembly 22. The emergency valve assembly 22 is connected to the steering valve assembly 14 through the first emergency pipeline 191 and to the brake valve assembly 15 through the second emergency pipeline 192. The oil passing through the emergency pump 21 is defined as emergency oil.

[0041] When engine 12 fails, emergency oil is supplied to steering valve assembly 14 via emergency valve assembly 22 and first emergency line 191, so that steering valve assembly 14 can supply oil to steering mechanism 171 for emergency steering.

[0042] Alternatively, emergency oil can be supplied to the lifting mechanism 174 via emergency valve assembly 22, first emergency pipeline 191, steering valve assembly 14, and first oil line 193 for emergency lifting;

[0043] Alternatively, emergency oil can be supplied to brake valve assembly 15 via emergency valve assembly 22 and second emergency pipeline 192. Brake valve assembly 15 then supplies oil to parking brake 172 via second oil line 194 to release the parking brake.

[0044] The following describes the situation where emergency pump 21 and emergency valve assembly 22 are activated to supply fuel in the event of an engine 12 failure.

[0045] like Figure 1 and Figure 4 As shown, the emergency valve assembly 22 includes a first oil inlet P1, a first reversing valve 221, a first oil outlet ES, and a second oil outlet EB. When emergency steering or emergency lifting is required, the first oil inlet P1 is connected to the first oil outlet ES, and the first oil inlet P1 is disconnected from the second oil outlet EB. The emergency oil from the emergency pump 21 enters the emergency valve assembly 22 through the first oil inlet P1, flows from the first oil outlet ES to the first emergency pipeline 191, and then enters the steering valve assembly 14 from the first emergency pipeline 191, realizing the emergency steering according to the driver's operation. In the emergency steering or emergency lifting function, when the emergency oil flow from the steering valve assembly 14 to the priority valve 161, and the steering mechanism 171 needs to be turned, the priority valve 161 is connected to the steering mechanism 171, and the emergency oil flows to the steering mechanism 171 through the priority valve 161; when the lifting mechanism 174 needs to be lifted, the first solenoid valve 141 is energized, and the sequence valve 142 connects the priority valve 161 and the first oil circuit 193, and the emergency oil flows to the lifting mechanism 174 after passing through the priority valve 161, the sequence valve 142, and the first oil circuit 193.

[0046] When the parking brake needs to be released, the first reversing valve 221 connects the first oil inlet P1 and the second oil outlet EB. The emergency oil from the emergency pump 21 flows through the first oil inlet P1, the first reversing valve 221, and the second oil outlet EB to the second emergency pipeline 192, and then enters the brake valve group 15 from the second pipeline to realize the relocation and maintenance of the dump truck.

[0047] Preferably, the hydraulic system further includes an emergency brake release button, which is electrically connected to the first directional valve 221. The emergency brake release button is used to switch the working position of the first directional valve 221. In addition, the first directional valve 221 can also be switched manually.

[0048] like Figure 4 As shown, the emergency valve assembly 22 also includes a pressure reducing valve 222, which is connected between the first oil inlet P1 and the first directional valve 221. Since the parking brake 172 only requires a small amount of oil pressure to release the parking brake, the pressure reducing valve 222 is used to reduce the pressure of the emergency oil flowing to the second emergency line 192.

[0049] Preferably, the emergency valve assembly 22 includes a first check valve 223, which is connected between the first oil inlet P1 and the first oil outlet ES. The emergency oil from the first oil inlet P1 flows to the first oil outlet ES through the first check valve 223. The first check valve 223 can ensure that the emergency oil can enter the steering valve assembly 14 normally when the engine 12 fails. When the engine 12 is not faulty, it prevents the oil in the steering valve assembly 14 in the hydraulic system from flowing back to the emergency valve assembly 22 through the first emergency pipeline.

[0050] like Figure 1 and Figure 3 As shown, the brake valve assembly 15 includes a shuttle valve 151, which is connected to the second oil circuit 194. When the engine 12 fails and the parking brake needs to be released, emergency oil flows through the second emergency line 192, the shuttle valve 151, and the second oil circuit 194 to the parking brake 172.

[0051] When a dump truck breaks down and loses power, the emergency operating principle is as follows:

[0052] (1) Emergency steering: When the engine 12 fails, the driver operates the emergency button in the cab. The motor 23 receives the start signal and starts to drive the emergency pump 21 to rotate. The emergency pump 21 pumps oil from the hydraulic oil tank 11 to the first oil port and enters the first valve group. After passing through the first check valve 223, it flows out from the first oil outlet ES and enters the first emergency pipeline 191. It enters the steering valve group 14 through the first emergency pipeline 191. It passes through the second check valve in the steering valve group 14 and then through the priority valve 161, the flow amplification valve and the steering mechanism 171 in sequence to realize the steering function.

[0053] (2) Emergency lifting: When lifting is required, the driver operates the lifting handle, the first solenoid valve 141 of the steering valve group 14 is energized, the sequence valve 142 connects the priority valve 161 and the first oil circuit 193, the emergency oil passes through the first emergency pipeline 191, the second check valve, the priority valve 161 and the sequence valve 142 in sequence, and then enters from the EF2 port of the steering valve group 14 and passes through the sequence valve 142, the first oil circuit 193 and the lifting mechanism 174 in sequence to realize emergency lifting.

[0054] (3) Emergency braking: When the engine 12 fails and the vehicle is in a parking brake state, making it impossible to transfer to another site for maintenance, the driver can operate the emergency brake release button in the cab to switch the first reversing valve 221 in the emergency valve group 22 to the left position to connect the first oil inlet P1 and the second oil outlet EB. Then, the driver can operate the emergency button in the cab, and the motor 23 will receive the start signal and start to drive the emergency pump 21 to rotate and supply oil to the emergency valve group 22. Since the pressure required to release the brake is less than the pressure of steering and lifting, a pressure reducing valve 222 is added to reduce the pressure of the emergency oil. After passing through the pressure reducing valve 222 and the first reversing valve 221, the emergency oil flows out from the second oil outlet EB and enters the second emergency pipeline 192. It flows through the second emergency pipeline 192 to the EPB port of the brake valve group 15, and flows through the shuttle valve 151 from the Pb port of the brake valve group 15 into the parking brake 172 to release the parking brake and achieve the purpose of transferring to another site for maintenance. If the emergency brake release button fails to activate and the first directional valve 221 reverses, the operating position of the first directional valve 221 can be manually switched to ensure timely relocation for maintenance.

[0055] The hydraulic system of this utility model is equipped with an emergency pump 21 and an emergency valve group 22. The emergency valve group 22 is connected to the steering valve group 14 through the first emergency pipeline 191. When the engine 12 fails, the emergency pump 21 and the emergency valve group 22 work together to quickly supply emergency oil to the steering mechanism 171 or the lifting mechanism 174 to realize emergency steering or emergency lifting functions. Unloading can be completed without the assistance of other vehicles. The emergency valve group 22 is connected to the brake valve group 15 through the second emergency pipeline 192. When the engine 12 fails and needs to be moved for maintenance, emergency oil can be quickly supplied to the parking brake 172 to release the parking brake and improve the relocation efficiency of the dump truck. The emergency pump 21 and the emergency valve group 22 of this hydraulic system are not only easy to install and simple to use, but also low in cost.

[0056] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the appended claims.

Claims

1. A hydraulic system characterized by, The system includes a hydraulic oil tank (11), an engine (12), a variable displacement pump (13), a steering valve assembly (14), a steering mechanism (171), a brake valve assembly (15), a parking brake (172), a lifting mechanism (174), an emergency pump (21), and an emergency valve assembly (22). The variable displacement pump (13) and the emergency pump (21) are respectively connected to the hydraulic oil tank (11). The engine (12) is connected to the variable displacement pump (13) to drive the variable displacement pump (13) to rotate. The steering valve assembly (14) is connected to the variable displacement pump (13) and is used to supply oil to the steering mechanism (171) to control steering. The lifting mechanism (174) is connected to the steering valve assembly (14) via the first oil passage (193); The brake valve assembly (15) is connected to the parking brake (172) via the second oil passage (194); The emergency valve assembly (22) is connected to the emergency pump (21), the emergency valve assembly (22) is connected to the steering valve assembly (14) through the first emergency pipeline (191), and the emergency valve assembly (22) is connected to the brake valve assembly (15) through the second emergency pipeline (192). The oil passing through the emergency pump (21) is defined as emergency oil; The emergency oil, via the emergency valve assembly (22), can be used for emergency steering, emergency lifting, and releasing the parking brake.

2. The hydraulic system of claim 1, wherein, The emergency valve assembly (22) is provided with a first oil inlet (P1), a first reversing valve (221), a first oil outlet (ES), and a second oil outlet (EB). When emergency steering or emergency lifting is required, the first oil inlet (P1) is connected to the first oil outlet (ES), and the first oil inlet (P1) is disconnected from the second oil outlet (EB). The emergency oil from the emergency pump (21) enters the emergency valve assembly (22) through the first oil inlet (P1) and then flows from the first oil outlet (ES) to the first emergency pipeline (191). The emergency oil is supplied to the steering valve assembly (14) via the first emergency pipeline (191), enabling the steering valve assembly (14) to supply oil to the steering mechanism (171) for emergency steering; When emergency steering is not required, the emergency oil is supplied to the lifting mechanism (174) via the first emergency line (191), the steering valve group (14), and the first oil line (193) for emergency lifting.

3. The hydraulic system of claim 1, wherein, The emergency valve assembly (22) is provided with a first oil inlet (P1), a first reversing valve (221), and a second oil outlet (EB). When it is necessary to release the parking brake, the first reversing valve (221) connects the first oil inlet (P1) and the second oil outlet (EB). The emergency oil of the emergency pump (21) flows through the first oil inlet (P1), the first reversing valve (221), and the second oil outlet (EB) to the second emergency pipeline (192). The second emergency pipeline (192) supplies oil to the brake valve assembly (15). The brake valve assembly (15) supplies oil to the parking brake (172) through the second oil circuit (194) to release the parking brake.

4. The hydraulic system of claim 3, wherein, The emergency valve assembly (22) also includes a pressure reducing valve (222), which is connected between the first oil inlet (P1) and the first directional valve (221). The pressure reducing valve (222) is used to reduce the pressure of the emergency oil flowing to the second emergency pipeline (192).

5. The hydraulic system of claim 4, wherein, The hydraulic system also includes an emergency brake release button, which is electrically connected to the first directional valve (221) and is used to switch the working position of the first directional valve (221). The first directional valve (221) can be manually switched in its operating position.

6. The hydraulic system of claim 1, wherein, The hydraulic system also includes a motor (23), which is connected to the emergency pump (21). The motor (23) can drive the emergency pump (21) to rotate to supply oil to the emergency valve group (22).

7. The hydraulic system of claim 2, wherein, The hydraulic system includes a flow amplification valve assembly (15), which is connected between the steering valve assembly (14) and the steering mechanism (171). The flow amplification valve assembly (15) includes a priority valve (161). When the emergency oil from the steering valve assembly (14) flows to the priority valve (161), the priority valve (161) is connected to the steering mechanism (171) when the steering mechanism (171) needs to turn. The emergency oil flows to the steering mechanism (171) through the priority valve (161).

8. The hydraulic system of claim 2, wherein, The steering valve assembly (14) includes a first solenoid valve (141) and a sequence valve (142). When the lifting mechanism (174) needs to lift, the first solenoid valve (141) is energized, and the sequence valve (142) connects the priority valve (161) and the first oil circuit (193). The emergency oil flows to the lifting mechanism (174) after passing through the priority valve (161), the sequence valve (142), and the first oil circuit (193).

9. The hydraulic system as described in claim 3, characterized in that, The brake valve assembly (15) includes a shuttle valve (151), which is connected to the second oil circuit (194). When the engine (12) fails and the parking brake needs to be released, the emergency oil flows through the second emergency line (192), the shuttle valve (151), and the second oil circuit (194) to the parking brake (172).

10. A dump truck characterized by Includes the hydraulic system as described in any one of claims 1 to 9.

Images