A priority steering load sensing system capable of isolating high voltage and a vehicle

Abstract

The present invention discloses a priority steering load-sensitive system and vehicle capable of isolating high pressure in the field of vehicle priority steering control technology, comprising a load-sensitive variable pump, a multi-way valve group, a steering gear, a priority valve, an amplifying valve group, an isolation valve and a pressure-controlled shuttle valve, wherein the oil inlet of the priority valve is connected to the load-sensitive variable pump, the CF port is connected to the oil inlet of the amplifying valve group and the oil inlet of the isolation valve, and the EF port is connected to the oil inlet of the multi-way valve group; the control port of the steering gear is connected to the LS port of the priority valve, and the oil inlet is connected to the oil outlet of the isolation valve; the oil inlet of the pressure-controlled shuttle valve is connected to the control port of the steering gear and the LS port of the multi-way valve group, and the oil outlet is connected to the LS port of the load-sensitive variable pump; the control end of the isolation valve is connected to the LS port of the multi-way valve group by signal. The present invention controls the on-off of the steering gear and the priority valve through the isolation valve, and controls the reversing of the isolation valve through the oil pressure of the LS port of the multi-way valve group, so as to realize the high-pressure isolation of the steering module during heavy-load operation.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle priority steering control, and in particular to a priority steering load-sensitive system capable of isolating high voltage and a vehicle. Background Art

[0002] Generally, large and medium-sized engineering vehicles based on full hydraulic steering, such as tank trucks, are generally equipped with large-flow hydraulic power steering, large-arm tipping, suspension lifting, lock hook opening and closing and other working devices driven by hydraulic cylinders, so as to complete the operation requirements of tank unloading, etc. The pursuit of safety, reliability, economy and efficiency has always been an important indicator for measuring the quality of hydraulic system design, especially for high-temperature iron slag transport vehicles in the field of metallurgical logistics, where safety indicators are placed first. In recent years, with the maturity of the metallurgical logistics market at home and abroad, an economically configured and efficient system is more likely to be favored by customers.

[0003] As the core components of the full hydraulic steering system, the rated working pressure of the flow amplification valve is not higher than 21MPa, and the rated pressure of the steering gear is not higher than 16MPa. Therefore, the full hydraulic steering system generally belongs to the medium and low pressure system, and the pipe fittings and other pipeline accessories are configured and selected as light-duty. However, some branches in the hydraulic system of the working device, such as the arm tipping branch, are high-pressure and high-flow circuits, which are generally required to withstand a maximum pressure of 28MPa, and the corresponding pipeline accessories must be configured and selected as heavy-duty.

[0004] In response to this phenomenon of uneven pressure, there are three common hydraulic control solutions on the market. The first is the discrete oil source solution, which ensures the independence of the oil sources for steering and boom tipping to achieve mutual isolation of high pressure and low pressure, but this solution has the disadvantages of high cost and poor economy. The second is the large flow switching valve isolation solution, that is, the control of the flow direction of hydraulic oil by a large-diameter electromagnetic reversing valve, closing the steering branch pressure channel when the boom tipping action, to achieve mutual separation of high pressure and low pressure, but this solution follows the switching idea of ​​high-pressure and large-flow valves, and the economy is also not high, and it is easy to cause switching shocks accompanied by obvious noise, and the reliability is not high. The third is the technical solution of using a priority valve to control the flow direction of hydraulic oil, that is, by distributing different flows of hydraulic oil to the steering system and the working system, not only the isolation of the steering system from the working system is achieved, but also the advantage of low cost. However, this solution only achieves the isolation of the steering system from the working system, but does not achieve the isolation of the working system from the steering system (the reason for not isolating is: in order to improve working efficiency, it is necessary to perform steering operations and no-load operations at the same time under medium and low pressure conditions). However, when the vehicle's working system is in a heavy-load operating state, accidental contact or misoperation of the steering system will cause the high-pressure hydraulic oil of the working system to flow to the steering system, which may not only easily cause steering system failure or damage, but also cause interruption of the working system operation, and in serious cases, production safety accidents may occur.

[0005] Therefore, how to prevent the high-pressure hydraulic oil of the working system from flowing to the steering system has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0006] In view of this, an object of the present invention is to provide a priority steering load sensing system capable of isolating high pressure, so as to solve the technical problem that the existing steering system cannot isolate and work the high pressure oil of the system.

[0007] The technical solution adopted by the present invention is: a priority steering load sensing system capable of isolating high voltage, comprising:

[0008] An oil supply module, the oil supply module comprising a load-sensitive variable displacement pump;

[0009] A working module, wherein the working module comprises a multi-way valve group;

[0010] A steering module, the steering module comprising a steering gear, a priority valve, an amplifying valve group and an isolation valve; the oil inlet of the priority valve is connected to a load-sensitive variable pump, the CF port is connected to the oil inlet of the amplifying valve group, and the EF port is connected to the oil inlet of the multi-way valve group; the control port of the steering gear is connected to the LS port of the priority valve, and the steering oil port is connected to the steering control oil port of the amplifying valve group; the oil inlet of the isolation valve is connected to the CF port of the priority valve, and the oil outlet is connected to the oil inlet of the steering gear;

[0011] A pressure control shuttle valve, wherein the two oil inlets of the pressure control shuttle valve are respectively connected to the control port of the steering gear and the LS port of the multi-way valve group, and the oil outlet is connected to the LS port of the load-sensing variable pump, so as to control the output oil pressure of the load-sensing variable pump;

[0012] Wherein, the control end of the isolation valve is connected to the LS port signal of the multi-way valve group for automatic high-pressure isolation of the steering gear.

[0013] Preferably, a control switch is provided on the LS pipeline between the LS port of the multi-way valve group and the pressure-controlled shuttle valve, the control switch is connected to the control end of the isolation valve, and the threshold of the control switch is greater than the LS port oil pressure when the working module is operating at no load, and is less than the LS port oil pressure when the working module is operating at heavy load.

[0014] Preferably, the threshold of the control switch is 8MPa to 12MPa.

[0015] Preferably, the isolation valve is a two-position three-way hydraulically controlled reversing valve, the control switch is a sequence valve, and the oil drain port of the sequence valve is connected to the hydraulic control end of the two-position three-way hydraulically controlled reversing valve, which is used to automatically isolate the steering gear when the working module is operating under heavy load.

[0016] Preferably, the isolation valve is a two-position three-way electromagnetic reversing valve, and the control switch is a pressure switch. The pressure switch is electrically connected to the control end of the two-position three-way electromagnetic reversing valve and is used to automatically isolate the steering gear when the working module is operating under heavy load.

[0017] Preferably, the working module also includes a boom tilting cylinder, a dual-line explosion-proof valve and a balancing valve group, the working oil port of the multi-way valve group is connected to the oil inlet of the balancing valve group, the oil outlet of the balancing valve group is connected to the boom tilting cylinder, and the dual-line explosion-proof valve is connected between the two boom tilting cylinders.

[0018] Preferably, the multi-way valve group includes an electronically controlled drive valve block, a proportional reversing valve and a pressure-selective shuttle valve; the oil inlet of the proportional reversing valve is connected to the EF port of the priority valve, and the working oil port is connected to the oil inlet of the balancing valve group; the electronically controlled drive valve block is a high-speed switching valve for controlling the reversing action of the proportional reversing valve; the two oil inlets of the pressure-selective shuttle valve are connected to the two LS ports of the proportional reversing valve in a one-to-one correspondence, and the oil outlet is connected to the oil inlet of the pressure-control shuttle valve.

[0019] Preferably, the hydraulic control system also includes an auxiliary function module, the auxiliary function module includes an oil supply pipeline and a hook lock branch, the oil supply module also includes a metering pump, and the metering pump is connected to the oil supply pipeline; the hook lock branch includes a hook lock cylinder, an accumulator, a first electromagnetic reversing valve and a two-way hydraulic lock, the oil inlet of the first electromagnetic reversing valve is connected to the oil supply pipeline, and the working oil port is connected to the hook lock cylinder through the hook lock pipeline, and the two-way hydraulic lock is arranged on the hook lock pipeline; a one-way oil inlet branch and a one-way oil replenishment branch are connected between the accumulator and the hook lock pipeline, the one-way oil inlet branch is used to store hydraulic oil, and the one-way oil replenishment branch is used to replenish hydraulic oil to the hook lock cylinder.

[0020] Preferably, the oil inlet end of the oil supply pipeline is connected to a two-way pipeline explosion-proof valve.

[0021] Preferably, the auxiliary function module includes an outrigger branch, which includes an outrigger cylinder, a balancing valve and a second solenoid reversing valve, the oil inlet of the second solenoid reversing valve is connected to the oil supply pipeline, the working oil port is connected to the outrigger cylinder through the outrigger pipeline, and the balancing valve is arranged at the rodless chamber oil port of the outrigger cylinder.

[0022] Preferably, there are two steering gears, the control ports of the two steering gears are connected to the two oil inlets of the pressure-controlled steering shuttle valve in a one-to-one correspondence, and the oil outlet of the pressure-controlled steering shuttle valve is connected to the LS port of the priority valve and the oil inlet of the pressure-controlled shuttle valve; the steering oil ports of the two steering gears are connected to the two oil inlets of the steering shuttle valve in a one-to-one correspondence, and the oil outlet of the steering shuttle valve is connected to the steering control oil port of the amplification valve group.

[0023] A second object of the present invention is to provide a vehicle comprising the above-mentioned priority steering load sensing system capable of isolating high voltage.

[0024] Beneficial effects of the present invention:

[0025] 1. The present invention adopts a method of controlling the flow direction of oil by oil pressure. First, a pressure control shuttle valve is arranged between the steering module and the working module, and the two oil inlets of the pressure control shuttle valve are connected to the control port of the steering gear and the LS port of the multi-way valve group one by one, and the oil outlet is connected to the LS port of the load-sensitive variable pump, so that the oil pressure signal of the steering module and the oil pressure signal of the working module are selected through the shuttle valve, and the output oil pressure of the load-sensitive variable pump is controlled to realize the control of the oil pressure of the hydraulic system; then an isolation valve is arranged between the oil inlet of the steering gear and the CF port of the priority valve, and the isolation valve is connected to the LS port signal of the working module, so that the on-off between the priority valve and the steering gear is controlled by the oil pressure signal of the LS port of the working module, so as to realize the automatic high-pressure isolation of the steering gear and prevent the high-pressure oil of the working module from entering the steering module.

[0026] 2. The present invention provides a control switch on the LS pipeline between the LS port of the working module and the pressure-controlled shuttle valve. The control switch is connected to the isolation valve signal and is used to control the on-off of the connecting pipeline between the priority valve and the steering gear. The opening pressure of the control switch is set to be greater than the LS port oil pressure of the working module during no-load operation and less than the LS port oil pressure of the working module during heavy-load operation. When the load-sensitive variable pump outputs medium and low-pressure hydraulic oil to the outside, the working module and the steering module are in a connected state, so that steering operations and no-load operations can be carried out simultaneously, thereby ensuring work efficiency; when the load-sensitive variable pump outputs high-pressure hydraulic oil to the outside, the working module and the steering module are in an isolated state to prevent the high-pressure oil of the working module from entering the steering module, and prohibit the steering module from performing steering operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of a priority steering load sensing system capable of isolating high voltage of the present invention;

[0028] Figure 2 It is a structural schematic diagram of the working module of the present invention;

[0029] Figure 3 It is a structural schematic diagram of the steering module of the present invention;

[0030] Figure 4 It is a structural schematic diagram of the oil supply module of the present invention;

[0031] Figure 5 It is a structural schematic diagram of the auxiliary function module of the present invention;

[0032] Figure 6The flow path diagram of the medium and low pressure oil of the steering module;

[0033] Figure 7 Flow path diagram of the high-pressure oil of the working module.

[0034] Description of reference numerals in the figures:

[0035] 100. Oil supply module;

[0036] 110, load-sensitive variable pump; 120, first pressure filter; 130, quantitative pump; 140, second pressure filter; 150, radiator; 160, return oil filter; 170, oil tank; 180, two-way pipeline explosion-proof valve;

[0037] 200, working module;

[0038] 210, multi-way valve group; 220, big arm tilting cylinder; 230, balance valve group; 240, double-line explosion-proof valve;

[0039] 211, proportional reversing valve; 212, pressure-selective shuttle valve; 213, second LS relief valve; 214, pressure compensation valve; 215, buffer oil replenishment valve; 216, pilot pressure reducing valve; 217, third relief valve; 218, electronically controlled drive valve block;

[0040] 331, flow amplifier; 332, hydraulically controlled proportional reversing valve; 333, buffer oil replenishing valve group;

[0041] 300, steering module;

[0042] 310, steering gear; 320, priority valve; 330, amplification valve group; 340, isolation valve; 350, first LS relief valve; 360, back pressure oil replenishment valve; 370, pressure control steering shuttle valve; 380, steering shuttle valve; 390, steering cylinder;

[0043] 400, pressure control shuttle valve;

[0044] 500, control switch;

[0045] 600, auxiliary function module;

[0046] 610, oil supply pipeline; 620, hook lock branch; 630, outrigger branch;

[0047] 611, oil inlet pipeline; 612, oil return pipeline; 613, electric pilot unloading relief valve;

[0048] 621, hook lock cylinder; 622, accumulator; 623, pressure sensor; 624, first electromagnetic reversing valve; 625, two-way hydraulic lock; 626, one-way oil replenishment branch; 627, one-way oil inlet branch; 628, first overflow valve; 629, hook lock pipeline;

[0049] 631, outrigger oil cylinder; 632, balancing valve; 633, outrigger pipeline; 634, second solenoid reversing valve; 635, second overflow valve. DETAILED DESCRIPTION

[0050] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. These embodiments are only used to illustrate the present invention, but not to limit the present invention.

[0051] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0052] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be fixed connection, detachable connection, or integrated connection; it can be mechanical connection or electrical connection; it can be directly connected or indirectly connected through an intermediate medium, or it can be internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] Furthermore, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0054] Examples, such as Figure 1-Figure 7 As shown, a priority steering load-sensing system capable of isolating high pressure is installed on an engineering vehicle and is used to prohibit high-pressure hydraulic oil from flowing to the steering system and prohibit the steering action of the steering system when the working system of the engineering vehicle performs heavy-load operations; the system includes:

[0055] An oil supply module 100 includes a load-sensitive variable displacement pump 110. The load-sensitive variable displacement pump 110 can deliver medium- and low-pressure hydraulic oil and high-pressure hydraulic oil to the outside as needed.

[0056] A working module 200 includes a multi-way valve group 210, and the working module 200 is used to perform heavy-load operations and no-load operations externally.

[0057] A steering module 300 is used to perform steering operations and includes a steering gear 310, a priority valve 320, an amplifying valve group 330 and an isolating valve 340; wherein the oil inlet of the priority valve 320 is connected to the load-sensitive variable pump 110, the CF port of the priority valve 320 is connected to the oil inlet of the amplifying valve group 330, and the EF port of the priority valve 320 is connected to the oil inlet of the multi-way valve group 210; the control port of the steering gear 310 is connected to the LS port of the priority valve 320, and the steering oil port of the steering gear 310 is connected to the steering control oil port of the amplifying valve group 330; the oil inlet of the isolating valve 340 is connected to the CF port of the priority valve 320, and the oil outlet of the isolating valve 340 is connected to the control port of the steering gear 310.

[0058] A pressure-controlled shuttle valve 400, one oil inlet of the pressure-controlled shuttle valve 400 is connected to the control port of the steering gear 310, the other oil inlet of the pressure-controlled shuttle valve 400 is connected to the LS port of the multi-way valve group 210, and the oil outlet of the pressure-controlled shuttle valve 400 is connected to the LS port of the load-sensitive variable pump 110. The pressure-controlled shuttle valve 400 is used to control the external output oil pressure of the load-sensitive variable pump 110.

[0059] The control end of the isolation valve 340 is signal-connected to the LS port of the multi-way valve group 210 for automatic high-pressure isolation of the steering gear 310 .

[0060] The present application adopts the method of controlling the flow direction of oil by oil pressure. First, a pressure control shuttle valve 400 is set between the steering module 300 and the working module 200, and the two oil inlets of the pressure control shuttle valve 400 are connected to the control port of the steering gear 310 and the LS port of the multi-way valve group one by one, and the oil outlet is connected to the LS port of the load-sensitive variable pump 110, so that the oil pressure signal of the steering module 300 and the oil pressure signal of the working module 200 are selected through the pressure control shuttle valve 400, and the external output oil pressure of the load-sensitive variable pump 110 is controlled to realize the control of the oil pressure of the hydraulic control system; then, an isolation valve 340 is set between the oil inlet of the steering gear 310 and the CF port of the priority valve 320, and the isolation valve 340 is connected to the LS port signal of the working module 200, so that the on-off between the priority valve 320 and the steering gear 310 is controlled by the oil pressure signal of the LS port of the working module 200, so as to realize the automatic high-pressure isolation of the steering gear 310 and prevent the high-pressure oil of the working module 200 from entering the steering module 300.

[0061] It should be noted that the control port of the steering gear 310 is also called the LS port of the steering gear 310; the CF port of the priority valve 320 is connected to the hydraulic control end.

[0062] In a specific embodiment, if Figure 1As shown, an LS pipeline is connected between the LS port of the multi-way valve group 210 and the oil inlet of the pressure control shuttle valve 400. A control switch 500 is provided on the LS pipeline. The control switch is connected to the control end of the isolation valve 340, and the threshold of the control switch is greater than the LS port oil pressure of the working module in no-load operation and less than the LS port oil pressure of the working module in heavy-load operation, so that when the working module 200 performs heavy-load operation, the isolation valve 340 is automatically disconnected to achieve high-pressure isolation of the steering gear 310 and prevent the high-pressure oil of the working module 200 from entering the steering module 300. The threshold refers to the opening pressure set for the control switch 500.

[0063] This setting is because: for engineering vehicles, there are three main actions driven by the hydraulic control system, namely: the steering operation of the steering system, the no-load operation and heavy-load operation of the working system. Among them, the steering system can only be driven by medium and low pressure hydraulic oil (not higher than 16MPa), the no-load operation of the working system can be driven by medium and low pressure hydraulic oil, but the heavy-load operation of the working system must be driven by high-pressure hydraulic oil (not less than 16MPa); at the same time, in order to ensure that the engineering vehicles have high working efficiency, it is necessary to enable the steering operation of the steering system and the no-load operation of the working system to be carried out at the same time.

[0064] In the embodiment, by setting a control switch 500 on the LS pipeline between the multi-way valve group 210 and the pressure control shuttle valve 400, the control switch 500 can detect the LS port oil pressure signal of the working module 200 used to control the load-sensitive variable pump 110. When the oil pressure signal is lower than the threshold value, it means that the working module 200 is performing no-load operation, the load-sensitive variable pump 110 outputs medium and low pressure hydraulic oil to the outside, and the control switch 500 has no control signal output, the isolation valve 340 is in a normally closed connected state, and the steering gear 310 and the priority valve 320 are in a connected state, so that the engineering vehicle can perform steering operations and no-load operations at the same time. When the oil pressure signal is greater than the threshold, it means that the working module 200 is performing heavy-load operations, and the load-sensitive variable pump 110 outputs high-pressure hydraulic oil to the outside. The control switch 500 outputs a control signal to control the isolation valve 340 to automatically disconnect, and to disconnect the steering gear 310 and the priority valve 320 to prevent the high-pressure hydraulic oil from entering the steering gear 310 and the amplification valve group 330 through the priority valve 320, and prohibiting the steering module 300 from performing steering actions to ensure the safety of the steering module 300 and the safety of the heavy-load operation of the working module 200.

[0065] Preferably, the threshold of the control switch 500 is 8MPa to 12MPa. This setting is because: for the tank truck, when the working module 200 is in an unloaded state, that is, when the high-temperature slag tank of the tank truck is not injected with a high-temperature solution, the oil pressure of the LS port of the multi-way valve group 210 is 5MPa to 8MPa; when the working module 200 is in a heavy-loaded state, that is, when the high-temperature slag tank of the tank truck is filled with a high-temperature solution, the oil pressure of the LS port of the multi-way valve group 210 is greater than 12MPa; therefore, setting the threshold of the control switch 500 to any value between 8MPa and 12MPa, such as 10MPa, can ensure that the steering operation and the empty seat operation are carried out at the same time, and the steering operation is prohibited during the heavy-load operation.

[0066] In a specific embodiment, if Figure 1 , Figure 6 , Figure 7 As shown, the isolation valve 340 is a two-position three-way hydraulically controlled reversing valve, the oil inlet P of the two-position three-way hydraulically controlled reversing valve is connected to the CF port of the priority valve, the oil outlet A is connected to the oil inlet P of the steering gear, and the oil return port T is connected to the oil tank 170; the control switch 500 is a sequence valve, and a three-way is provided on the LS pipeline, the oil inlet of the three-way is connected to the LS port of the multi-way valve group 210, one oil outlet is connected to an oil inlet of the pressure control shuttle valve 400, and the other oil outlet is connected to the oil inlet of the sequence valve, and the oil outlet of the sequence valve is connected to the hydraulic control end of the two-position three-way hydraulically controlled reversing valve; when the working module 200 performs heavy-load operation, the pressure signal of the LS port of the multi-way valve group 210 is obtained through the sequence valve, and the two-position three-way hydraulically controlled reversing valve is controlled to automatically disconnect the connection between the priority valve 320 and the steering gear 310, so as to realize high-pressure isolation of the steering gear 310.

[0067] This arrangement is made because: the sequence valve is a mechanical valve, which has the advantages of simple structure and easy use; connecting the sequence valve with the LS pipeline between the LS port of the multi-way valve group 210 and the oil inlet of the pressure control shuttle valve 400 can not only realize the direct connection between the LS port of the multi-way valve group 210 and the oil inlet of the pressure control shuttle valve 400, but also automatically control the reversing of the two-position three-way hydraulically controlled reversing valve after the oil pressure at the LS port of the multi-way valve group 210 exceeds the threshold value, so as to isolate the steering gear 310, thereby preventing the high-pressure hydraulic oil of the working module 200 from flowing to the steering module 300.

[0068] In a specific embodiment, if Figure 1As shown, the isolation valve 340 is a two-position three-way solenoid reversing valve, the oil inlet P of the two-position three-way solenoid reversing valve is connected to the CF port of the priority valve, the oil outlet A is connected to the oil inlet P of the steering gear 310, and the oil return port T is connected to the oil tank 170; the control switch 500 is a pressure switch, and the pressure switch is electrically connected to the control end of the two-position three-way solenoid reversing valve, and is used to automatically control the two-position three-way solenoid reversing valve to be electrically switched when the oil pressure at the LS port of the multi-way valve group 210 exceeds the threshold value, thereby preventing the high-pressure hydraulic oil of the working module 200 from flowing to the steering module 300.

[0069] The reason for such arrangement is that: the two-position three-way solenoid reversing valve controls the on and off of the valve by electricity, which is convenient for arranging the connection lines; the pressure switch is arranged on the LS pipeline between the LS port of the multi-way valve group 210 and the oil inlet of the pressure control shuttle valve 400, which will not only not affect the flow of hydraulic oil in the LS pipeline, but also control the two-position three-way solenoid reversing valve to quickly reverse after the oil pressure at the LS port of the multi-way valve group 210 exceeds the threshold value, so as to isolate the steering gear 310, thereby preventing the high-pressure hydraulic oil of the working module 200 from flowing to the steering module 300.

[0070] In a specific embodiment, if Figure 1 , Figure 2 As shown, the working module 200 includes a multi-way valve group 210, a boom tilting cylinder 220, a dual-line explosion-proof valve 240 and a balancing valve group 230; wherein, the oil inlet of the multi-way valve group 210 is connected to the EF port of the priority valve, the two working oil ports of the multi-way valve group 210 are connected one-to-one with the two oil inlets of the balancing valve group 230, the two oil outlets of the balancing valve group 230 are connected one-to-one with the rod chamber and the rodless chamber of the boom tilting cylinder 220, and the dual-line explosion-proof valve 240 is connected between the two boom tilting cylinders 220.

[0071] The reason for this arrangement is that: a balancing valve group 230 is set between the multi-way valve group 210 and the boom tilting cylinder 220, which can automatically close the oil inlet and outlet of the boom tilting cylinder 220 after the connecting pipeline bursts, thereby preventing the hydraulic oil from leaking and preventing the occurrence of load failure; a double-line explosion-proof valve 240 is set on the connecting pipeline between the two boom tilting cylinders 220, which can automatically isolate the burst pipeline after one of the connecting pipelines bursts, thereby preventing the hydraulic oil from leaking, and continue to supply oil through the other connecting pipeline.

[0072] In a specific embodiment, if Figure 2As shown, the multi-way valve group 210 includes an electrically controlled drive valve block 218, a proportional reversing valve 211 and a pressure-selective shuttle valve 212. The oil inlet of the proportional reversing valve 211 is connected to the EF port of the priority valve 320, and the working oil port is connected to the oil inlet of the balance valve group 230; the electrically controlled drive valve block 218 is a high-speed switching valve or a proportional current type, which is used to control the reversing action of the proportional reversing valve 211; the two oil inlets of the pressure-selective shuttle valve 212 are connected to the two LS ports of the proportional reversing valve 211 in a one-to-one correspondence, and the oil outlet is connected to the oil inlet of the pressure control shuttle valve 400.

[0073] This is done because: the high-speed switch valve contains a valve core displacement sensor, which can monitor and feedback the valve core position in real time, and adjust the duty cycle through a dedicated controller to achieve precise adjustment of the proportional reversing valve 211. The two oil inlets of the pressure-selective shuttle valve 212 are connected to the two LS ports of the proportional reversing valve 211, so that when the proportional reversing valve 211 is in a non-neutral position, the oil pressure of the hydraulic oil inside the multi-way valve group 210 can be accurately obtained and fed back to the load-sensitive variable pump 110 to control the size of the oil pressure output by the load-sensitive variable pump 110.

[0074] Preferably, the multi-way valve group 210 further includes a pressure compensating valve 214 , a second LS relief valve 213 , a buffer oil replenishing valve 215 , a pilot pressure reducing valve 216 and a third relief valve 217 ; the pressure compensating valve 214 is arranged between the proportional reversing valve 211 and the priority valve 320 .

[0075] More preferably, the proportional reversing valve 211 is provided with a manual operating handle and a spare external power pilot emergency oil port M.

[0076] In a specific embodiment, if Figure 4 , Figure 5 As shown, the hydraulic control system also includes an auxiliary function module 600, which includes an oil supply pipeline 610 and a hook lock branch 620, and the oil supply module 100 also includes a metering pump 130; wherein, the oil supply pipeline 610 includes an incoming oil pipeline 611 and an oil return pipeline 612 arranged in parallel, and an electrically controlled pilot unloading relief valve is connected between the incoming oil pipeline 611 and the return oil pipeline 612; one end of the incoming oil pipeline 611 is connected to the oil outlet of the second pressure filter 140, the metering pump 130 is connected to the oil inlet end of the second pressure filter 140, one end of the return oil pipeline 612 is connected to the oil inlet of the radiator 150, and the oil outlet of the radiator 150 is connected to the oil tank 170, and the metering pump 130 is used to deliver low-pressure and small-flow hydraulic oil to the auxiliary function module 600.

[0077] This is set up because: except for the boom tipping cylinder 220 with high pressure and large flow requirements, the other auxiliary actions of the tanker, such as hanging legs, locking hooks and other auxiliary actions, belong to low-pressure and small-flow branches, which have the characteristics of short single operation time and low power required. However, the pipeline layout is long, generally from the pump source of the front vehicle to the periphery of the rear vehicle frame, especially the pipeline near the high-temperature slag tank. For example, the locking hook is used to fix the ear shafts on both sides of the high-temperature slag tank, and there are also leg cylinders 631 distributed on both sides of the high-temperature slag tank. For these auxiliary actions involving safety, the current hydraulic control system design is a high-pressure and high-flow oil source that shares the EF port of the priority valve 320, which has the disadvantages of low system operation efficiency and is not conducive to the safety design of explosion-proof for specific pipelines. In the present application, an auxiliary function module 600 and a metering pump 130 are provided, and low-pressure and low-flow hydraulic oil can be delivered to the auxiliary function module through the metering pump 130.

[0078] Preferably, the metering pump 130 is a gear pump and has an internal unloading valve. When the two-way pipeline explosion-proof valve 180 on the oil supply line 610 is started, the oil circuit of the oil outlet of the metering pump 130 is blocked, and internal emergency unloading can be achieved by the metering pump 130 itself.

[0079] In a specific embodiment, if Figure 5 As shown, the hook lock branch 620 includes a hook lock cylinder 621, an accumulator 622, a first electromagnetic reversing valve 624 and a two-way hydraulic lock 625. The oil inlet of the first electromagnetic reversing valve 624 is connected to the incoming oil pipeline 611, and the oil outlet is connected to the return oil pipeline 612. The two working oil ports are respectively connected to the rod chamber and the rodless chamber of the hook lock cylinder 621 through two hook lock pipelines 629, so as to deliver hydraulic oil to the two hook lock cylinders 621; the two-way hydraulic lock 625 is arranged on the two hook lock pipelines 629, so as to prevent the hydraulic oil from flowing in the two hook lock pipelines 629 in reverse at the same time. A pressure sensor 623 is provided on the hook lock pipeline 629, and the pressure sensor 623 is used to detect whether there is internal leakage in the hook lock cylinder 621, and a one-way oil inlet branch 627 and a one-way oil replenishment branch 626 are connected between the accumulator 622 and the hook lock pipeline 629 (which is connected to the rod cavity of the hook lock cylinder 621). The one-way oil inlet branch 627 is used to store hydraulic oil, and the one-way oil replenishment branch 626 is used to replenish hydraulic oil to the hook lock cylinder 621.

[0080] The reason for such arrangement is that: when the proportional reversing valve 211 of the multi-way valve group 210 is in a non-neutral working position, the hook needs to be kept in a reliable closed state during the process of the upper arm tilting cylinder 220 lifting and lowering the slag pot, so as to ensure that the slag pot ear axis will not fall off. However, when the hook lock cylinder 621 leaks internally, it will cause insufficient pressure, and the lock hook will be passively opened under external force. In this embodiment, by setting a two-way hydraulic lock 625 on the hook lock pipeline 629 between the first electromagnetic reversing valve 624 and the hook lock cylinder 621, not only can the reverse flow of hydraulic oil in the hook lock pipeline 629 be effectively prevented, but also the hydraulic oil output by the accumulator 622 through the one-way oil replenishment branch 626 can flow to the hook lock cylinder 621, and the hydraulic oil inside the hook lock cylinder 621 can be replenished in real time to maintain the stability of the oil pressure inside the hook lock cylinder 621.

[0081] Specifically, the one-way oil inlet branch 627 includes an oil inlet pipeline and a first one-way valve, one end of the oil inlet pipeline is connected to the hook lock pipeline 629 between the first solenoid reversing valve 624 and the two-way hydraulic lock 625 (the hook lock pipeline 629 is connected to the rod chamber of the hook lock cylinder 621), and the other end is connected to the accumulator 622; the first one-way valve is arranged on the oil inlet pipeline, and the oil inlet port of the first one-way valve is connected to the working oil port of the first solenoid reversing valve 624, and the oil outlet port is connected to the accumulator 622, which is used to distribute hydraulic oil to the accumulator 622. The one-way oil replenishment branch 626 includes an oil replenishment pipeline and a second one-way valve, one end of the oil replenishment pipeline is connected to the hook lock pipeline 629 between the two-way hydraulic lock 625 and the hook lock cylinder 621 (the hook lock pipeline 629 is connected to the rod chamber of the hook lock cylinder 621), and the other end is connected to the accumulator 622; the second one-way valve is arranged on the oil replenishment pipeline, and the oil inlet of the second one-way valve is connected to the accumulator 622, and the oil outlet is connected to the hook lock cylinder 621, which is used to replenish hydraulic oil into the hook lock cylinder 621.

[0082] Preferably, the one-way oil replenishment branch 626 is also connected to the oil return line 612 through a first relief valve 628 to limit the maximum oil pressure inside the accumulator 622 .

[0083] In a specific embodiment, if Figure 1 , Figure 4As shown, a two-way pipeline explosion-proof valve 180 is connected to one end of the incoming oil pipeline 611, and the two-way pipeline explosion-proof valve 180 is arranged between the second pressure filter 140 and the auxiliary function module 600. Such arrangement is because: since the hook lock branch 620 and the leg branch 630 of the auxiliary function module 600 are relatively close to the high-temperature tank body, pipe explosion is prone to occur. In this embodiment, when the internal pipeline of the auxiliary function module 600 explodes, the two-way pipeline explosion-proof valve 180 can cut off the pump port oil source in time, which can effectively prevent the oil in the oil tank 170 from continuing to spray out; when the inlet pipeline of the two-way pipeline explosion-proof valve 180 explodes, it can also prevent the oil source of the oil cylinder from flowing back, preventing the occurrence of dangerous situations such as the leg underpassing or the lock hook being released.

[0084] In a specific embodiment, the auxiliary function module 600 also includes a leg branch 630, which includes a leg cylinder 631, a balancing valve 632 and a second solenoid reversing valve 634; wherein, the oil inlet of the second solenoid reversing valve 634 is connected to the incoming oil pipeline 611, and the oil return port is connected to the return oil pipeline 612, and the two working oil ports are respectively connected to the rod chamber and the rodless chamber of the two leg cylinders 631 through two leg pipelines 633, and the balancing valve 632 is set at the rodless chamber oil port of the leg cylinder 631 and is connected to one of the leg pipelines 633, and the other leg pipeline 633 is connected to the oil supply pipeline 610 through the second overflow valve 635, which is used to overflow the leg pipeline 633.

[0085] This is set up because: for engineering vehicles, such as U-shaped tank trucks, the suspension frame needs to be suspended and supported by the outrigger branch 630, but during long-term use, the outrigger branch 630 is prone to bursting and leaking. In this embodiment, by installing a balance valve 632 at the oil port of the rodless chamber of the outrigger cylinder 631, and connecting the oil inlet of the balance valve 632 with the working oil port of the second electromagnetic reversing valve 634, the rodless chamber of the outrigger cylinder 631 can be actively closed after the outrigger pipeline 633 bursts, preventing the occurrence of load failure and falling.

[0086] In a specific embodiment, if Figure 1 , Figure 3 As shown, the number of the steering gear 310 can be one or two. When the number of the steering gear 310 is one, it is necessary to connect the left steering port of the steering gear 310 with the left steering control port of the amplifying valve group 330, connect the right steering control port of the steering gear 310 with the right steering control port of the amplifying valve group 330, and connect the control port of the steering gear 310 with the LS port of the priority valve 320 and the oil inlet of the pressure control shuttle valve 400 respectively through a connecting pipeline.

[0087] When there are two steering gears 310, namely the front steering gear and the rear steering gear, it is necessary to first connect the control ports of the front steering gear and the rear steering gear to the two oil inlets of a pressure-controlled steering shuttle valve 370 one by one, and then connect the oil outlet of the pressure-controlled steering shuttle valve 370 to the LS port of the priority valve 320 and the oil inlet of the pressure-controlled shuttle valve 400 respectively; at the same time, it is necessary to connect the left steering oil port of the front steering gear and the right steering oil port of the rear steering gear to the two oil inlets of the first steering shuttle valve 380 respectively, and then connect the oil outlet of the first steering shuttle valve 380 to the left steering control oil port of the amplifying valve group 330 respectively; connect the right steering oil port of the front steering gear and the left steering oil port of the rear steering gear to the two oil inlets of the second steering shuttle valve 380 respectively, and then connect the oil outlet of the second steering shuttle valve 380 to the right steering control oil port of the amplifying valve group 330 respectively.

[0088] This arrangement is because: a front steering gear is set at the front of the engineering vehicle, and a rear steering gear is set at the rear of the engineering vehicle. The engineering vehicle can be driven to steer by rotating different steering gears 310, thereby achieving control of the vehicle steering at different positions.

[0089] In a specific embodiment, if Figure 1 , Figure 3 As shown, the steering module 300 also includes a steering cylinder 390, a back pressure oil replenishment valve 360 ​​and a first LS relief valve 350, and the amplification valve group 330 includes a buffer oil replenishment valve group 333, a hydraulic proportional reversing valve 332 and a flow amplifier 331; wherein the oil inlet of the flow amplifier 331 is connected to the CF port of the priority valve 320; the oil outlet is connected to the oil inlet of the hydraulic proportional reversing valve 332, and the steering control oil port is connected to the steering oil port of the steering gear 310, The two working oil ports are connected to the rod chamber and rodless chamber of the steering cylinder 390 respectively, and the return oil port is connected to the oil inlet of the return oil filter 160 through the back pressure oil replenishing valve 360, and the oil outlet of the return oil filter 160 is connected to the oil tank 170; the oil inlet of the first LS overflow valve 350 is connected to the LS port of the priority valve 320, and the oil outlet is connected to the oil inlet of the back pressure oil replenishing valve 360, which is used to overflow the control hydraulic oil flowing from the steering gear 310 to the priority valve 320.

[0090] An embodiment of a vehicle includes the above-mentioned priority steering load sensing system capable of isolating high voltage.

[0091] Preferably, the weighing is done by a tank truck or a loader.

[0092] The use process of the tooling of the present invention is as follows:

[0093] In the standby state, the hydraulic oil pumped out by the load-sensitive variable pump 110 (variable plunger pump) enters the oil inlet of the priority valve 320. At this time, the priority valve 320 is in the priority position, and the hydraulic oil flows out from the CF port of the priority valve 320. Most of the hydraulic oil flows to the oil inlet of the hydraulically controlled proportional reversing valve 332, and a small part of the hydraulic oil flows to the oil inlet of the steering gear 310 through the isolation valve 340. At this time, only the steering operation of the vehicle can be performed.

[0094] like Figure 6 As shown, the steering gear 310 is controlled by the steering wheel, and a part of the control hydraulic oil flowing out of the control port of the steering gear 310 flows to the spring end of the priority valve 320, and this part of the hydraulic oil keeps the priority valve 320 in the priority position state, and the other part flows to the load-sensitive variable pump 110 to control the load-sensitive variable pump 110 to output medium and low pressure hydraulic oil to the outside; the hydraulic oil flowing out of the left steering oil port of the steering gear 310 flows to the left steering control oil port of the hydraulic-controlled proportional reversing valve 332, and this part of the hydraulic oil first switches the hydraulic-controlled proportional reversing valve 332 from the middle position to the left position, thereby making most of the hydraulic oil flowing out of the CF port of the priority valve 320 enter the steering cylinder 390 through the hydraulic-controlled proportional reversing valve 332, the flow amplifier 331 and the buffer oil replenishing valve group 333, and drive the vehicle to perform a left steering action; at the same time, the control hydraulic oil entering the hydraulic-controlled proportional reversing valve 332 from the left steering control oil port will merge in the flow amplifier 331 and finally flow to the steering cylinder 390.

[0095] During this process, since the priority valve 320 is in the priority position, no hydraulic oil flows to the oil inlet of the multi-way valve group 210, so the working module 200 does not act.

[0096] like Figure 7 As shown, when the steering gear 310 is not in motion, the hydraulic oil flowing out from the CF port of the priority valve 320 flows to the hydraulic control end of the priority valve 320, and controls the priority valve 320 to switch from the priority position to the working position, so that most of the hydraulic oil pumped out by the load-sensitive variable pump 110 flows to the multi-way valve group 210 through the EF port of the priority valve 320. Under the action of the proportional reversing valve 211, the hydraulic oil output by the multi-way valve group 210 enters the boom tilting cylinder 220, so that the working module 200 performs no-load operation or heavy-load operation.

[0097] When the working module 200 performs heavy-load operations, the oil pressure of the control hydraulic oil flowing out of the LS port of the multi-way valve group 210 is higher than 12MPa. The control hydraulic oil flows to the load-sensitive variable pump 110 through the pressure-control shuttle valve 400, and controls the load-sensitive variable pump 110 to output high-pressure oil to the outside; at the same time, the control switch 500 between the LS port of the multi-way valve group 210 and the pressure-control shuttle valve 400 sends a control signal to the isolation valve 340, and controls the isolation valve 340 to disconnect the priority valve 320 and the steering gear 310, so that the high-pressure oil pumped out by the load-sensitive variable pump 110 cannot enter the steering gear 310 and the amplification valve group 330, so as to prohibit the steering operation of the steering module 300 when the working module 200 performs heavy-load operations.

[0098] Compared with the prior art, this application has at least the following beneficial technical effects:

[0099] 1. This application strengthens the safety design of the hydraulic control system, reduces system configuration costs, and improves system efficiency.

[0100] 2. The pressure oil pumped out by the metering pump in this application is filtered and then returned to the oil inlet, which is directly connected to the radiator's inlet. The return oil of the radiator is directly connected to the oil tank, thereby realizing a circulation loop of the constant flow system in which the oil is filtered first and then dissipated, thereby ensuring the reliability of the entire working hydraulic system.

[0101] 3. The present application provides an accumulator for oil replenishment and pressure stabilization on the lock hook branch line. When the boom tipping cylinder is actuated, the cavity pressure of the lock hook cylinder with the lock hook closed is detected by the pressure sensor to be lower than the set pressure, and the corresponding first solenoid reversing valve will automatically be energized and loaded until the cavity pressure of the lock hook cylinder reaches the set value. At the same time, during heavy load operation, when the pressure sensor detects that the cavity pressure of the lock hook cylinder is lower than the set pressure, the accumulator can be used to replenish oil and pressure to the lock hook cylinder, thereby ensuring safe control during the tank lifting and unloading process.

[0102] 4. When the boom tipping cylinder is in action, the present application can cut off the high-pressure oil of the same system from flowing to the steering system through an isolation valve installed on the steering gear inlet pipeline, thereby preventing harmful impact of high pressure on steering system components and preventing vehicle shaking caused by accidental touching of the steering wheel, thereby improving the working safety of the boom and also helping to reduce the cost of high-pressure isolation.

[0103] 5. The pipelines of the auxiliary function module of the present application are spread throughout the actuators of the front and rear frames of the vehicle, especially the lock hook branch and the support leg branch near the high-temperature tank body. The risk of pipe explosion is relatively higher. The two-way pipeline explosion-proof valve installed at the outlet of the metering pump is conducive to controlling the explosion of the pipeline and preventing the leakage of oil at the outlet of the metering pump, thereby improving the safety of on-site operations.

[0104] 6. This application can associate the lock hook branch when the boom is working, cooperate with the pressure sensor monitoring to achieve interlocking loading, and realize double self-control pressure maintenance to ensure that the lock hook branch works more reliably.

[0105] 7. The electrically controlled drive valve block of the multi-way valve group of the present application adopts a high-speed switching valve, which is beneficial to improving the control accuracy of the boom; the proportional reversing valve is equipped with an external pilot control oil port and an operating handle, which can improve the emergency operation function.

[0106] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A priority steering load sensing system capable of isolating high voltage, characterized in that: include: An oil supply module (100), the oil supply module (100) comprising a load-sensitive variable displacement pump (110); A working module (200), wherein the working module (200) comprises a multi-way valve group (210); A steering module (300), the steering module (300) comprising a steering gear (310), a priority valve (320), an amplifying valve group (330) and an isolation valve (340); the oil inlet of the priority valve (320) is in communication with a load-sensitive variable pump (110), the CF port is in communication with the oil inlet of the amplifying valve group (330), and the EF port is in communication with the oil inlet of the multi-way valve group (210); the control port of the steering gear (310) is in communication with the LS port of the priority valve (320), and the steering oil port is in communication with the steering control oil port of the amplifying valve group (330); the oil inlet of the isolation valve (340) is in communication with the CF port of the priority valve (320), and the oil outlet is in communication with the oil inlet of the steering gear (310); a pressure-controlled shuttle valve (400), wherein two oil inlets of the pressure-controlled shuttle valve (400) are respectively connected to a control port of a steering gear (310) and an LS port of a multi-way valve group (210), and an oil outlet is connected to an LS port of a load-sensitive variable pump (110), and is used to control the output oil pressure of the load-sensitive variable pump (110); The control end of the isolation valve (340) is signal-connected to the LS port of the multi-way valve group (210) for automatic high-pressure isolation of the steering gear (310), and a control switch (500) is provided on the LS pipeline between the LS port of the multi-way valve group (210) and the pressure control shuttle valve (400), the control switch (500) being connected to the control end of the isolation valve (340), and the threshold value of the control switch (500) being greater than the LS port oil pressure of the working module (200) in no-load operation and less than the LS port oil pressure of the working module (200) in heavy-load operation.

2. A priority steering load sensing system capable of isolating high voltage according to claim 1, characterized in that: The threshold value of the control switch (500) is 8 MPa to 12 MPa.

3. A priority steering load sensing system capable of isolating high voltage according to claim 2, characterized in that: The isolation valve (340) is a two-position three-way hydraulically controlled reversing valve, the control switch (500) is a sequence valve, and the oil drain port of the sequence valve is connected to the hydraulic control end of the two-position three-way hydraulically controlled reversing valve, so as to automatically isolate the steering gear (310) when the working module (200) is in heavy-load operation; or The isolation valve (340) is a two-position three-way electromagnetic reversing valve, and the control switch (500) is a pressure switch. The pressure switch is electrically connected to the control end of the two-position three-way electromagnetic reversing valve and is used to automatically isolate the steering gear (310) when the working module (200) is in heavy-load operation.

4. A priority steering load sensing system capable of isolating high voltage according to claim 1, characterized in that: The working module (200) further comprises a boom tilting oil cylinder (220), a dual-line explosion-proof valve (240) and a balancing valve group (230); the working oil port of the multi-way valve group (210) is connected to the oil inlet of the balancing valve group (230); the oil outlet of the balancing valve group (230) is connected to the boom tilting oil cylinder (220); and the dual-line explosion-proof valve (240) is connected between the two boom tilting oil cylinders (220).

5. A priority steering load sensing system capable of isolating high voltage according to claim 4, characterized in that: The multi-way valve group (210) comprises an electrically controlled drive valve block (218), a proportional reversing valve (211) and a pressure-selective shuttle valve (212); the oil inlet of the proportional reversing valve (211) is connected to the EF port of the priority valve (320), and the working oil port is connected to the oil inlet of the balancing valve group (230); the electrically controlled drive valve block (218) is a high-speed switch valve, used to control the reversing action of the proportional reversing valve (211); the two oil inlets of the pressure-selective shuttle valve (212) are connected to the two LS ports of the proportional reversing valve (211) in a one-to-one correspondence, and the oil outlet is connected to the oil inlet of the pressure-control shuttle valve (400).

6. A priority steering load sensing system capable of isolating high voltage according to claim 1, characterized in that: The priority steering load-sensing system further comprises an auxiliary function module, the auxiliary function module comprises an oil supply pipeline (610) and a hook lock branch (620), the oil supply module (100) further comprises a metering pump (130), the metering pump (130) is in communication with the oil supply pipeline (610); the hook lock branch (620) comprises a hook lock oil cylinder (621), an accumulator (622), a first electromagnetic reversing valve (624) and a bidirectional hydraulic lock (625), the oil inlet of the first electromagnetic reversing valve (624) The working oil port is connected to the oil supply pipeline (610), and the working oil port is connected to the hook lock cylinder (621) through the hook lock pipeline (629), and the bidirectional hydraulic lock (625) is arranged on the hook lock pipeline (629); a one-way oil inlet branch (627) and a one-way oil replenishment branch (626) are connected between the accumulator (622) and the hook lock pipeline (629), and the one-way oil inlet branch (627) is used to store hydraulic oil, and the one-way oil replenishment branch (626) is used to replenish hydraulic oil to the hook lock cylinder (621).

7. A priority steering load sensing system capable of isolating high voltage according to claim 6, characterized in that: The oil inlet end of the oil supply pipeline (610) is connected to a two-way pipeline explosion-proof valve (180).

8. A priority steering load sensing system capable of isolating high voltage according to claim 6, characterized in that: The auxiliary function module includes an outrigger branch (630), and the outrigger branch (630) includes an outrigger oil cylinder (631), a balancing valve (632) and a second electromagnetic reversing valve (634). The oil inlet of the second electromagnetic reversing valve (634) is connected to the oil supply pipeline (610), and the working oil port is connected to the outrigger oil cylinder (631) through the outrigger pipeline (633), and the balancing valve (632) is arranged at the rodless chamber oil port of the outrigger oil cylinder (631).

9. A priority steering load sensing system capable of isolating high voltage according to claim 1, characterized in that: There are two steering gears (310), the control ports of the two steering gears (310) are connected to the two oil inlets of the pressure-controlled steering shuttle valve (370) in a one-to-one correspondence, and the oil outlet of the pressure-controlled steering shuttle valve (370) is connected to the LS port of the priority valve (320) and the oil inlet of the pressure-controlled shuttle valve (400); the steering oil ports of the two steering gears (310) are connected to the two oil inlets of the steering shuttle valve (380) in a one-to-one correspondence, and the oil outlet of the steering shuttle valve (380) is connected to the steering control oil port of the amplification valve group (330).

10. A vehicle, characterized in that: A priority steering load sensing system capable of isolating high voltage as described in any one of claims 1-9.

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