CN215719881U

CN215719881U - Electro-hydraulic control system and tractor

Info

Publication number: CN215719881U
Application number: CN202121686026.8U
Authority: CN
Inventors: 申屠军阳; 付颜红; 范道平
Original assignee: Weichai Lovol Heavy Industry Co Ltd
Current assignee: Weichai Lovol Intelligent Agricultural Technology Co Ltd
Priority date: 2021-07-23
Filing date: 2021-07-23
Publication date: 2022-02-01
Anticipated expiration: 2031-07-23

Abstract

The utility model relates to an electro-hydraulic control system and a tractor, which comprise a steering device, a multi-way valve device, a variable plunger pump and a steering priority valve, wherein an oil outlet I of the variable plunger pump is communicated with an oil inlet of the steering priority valve through a pipeline, and two oil outlets of the steering priority valve are respectively communicated with an oil inlet of the steering device and an oil inlet of the multi-way valve device through pipelines. The hydraulic control system has the advantages of high response speed, high control precision, convenience in operation and the like, and simplifies a hydraulic pipeline; the device has a constant speed control function and can switch a high maneuverability or high economy mode; the working performance and the service life of the wet clutch are improved; the constant power function can ensure that the engine works in the best economic condition.

Description

Electro-hydraulic control system and tractor

Technical Field

The utility model relates to the technical field of tractors, in particular to an electro-hydraulic control system and a tractor.

Background

The tractor is the most important member of agricultural machinery plate, related products are supported by the key of the country, and after more than ten years of development, the production process and research and development strength of a tractor main engine plant are rapidly improved, so that intelligent tractor products are diversified. The outstanding performance of the integration of the mechanical and electrical liquids after being applied to a tractor product, namely the service performance, the product quality and the operation comfort of the product are greatly improved.

The traditional tractor can be provided with no electro-hydraulic control system, the modern tractor can not be provided with the electro-hydraulic control system, and a load sensitive electro-hydraulic control system is arranged on a large-sized and medium-sized tractor, so that the energy conservation and emission reduction of corresponding products are greatly improved.

The electro-hydraulic control system comprises a closed center type load sensing system and an open type quantitative system. The load sensing system transmits the maximum load pressure of the steering system and the multi-way valve working system back to the variable displacement device of the variable plunger pump through the load sensing module, and the variable displacement device automatically adjusts the displacement of the variable plunger pump after comparing the sum of the load pressure and the fixed spring force with the outlet pressure of the variable plunger pump, so that the power required by the working device is provided, and the purposes of energy conservation and emission reduction are achieved. In addition, an oil cooling system and a lubricating system are arranged in the open type quantitative system to ensure the normal work of the transmission case and the wet clutch. The above prior art has the following disadvantages:

a. under any working condition, the pump outlet pressure is higher than the load pressure, the difference value is a pressure value (about 20bar) corresponding to the fixed spring force in the variable displacement device, certain power loss exists, and the larger the flow required by the system is, the larger the power loss is;

b. the maximum load is transmitted to the pump variable mechanism through a hydraulic pipeline, the dynamic response is slow, and meanwhile, the fluctuation of a low-pressure control oil source can be caused;

c. the load sensing module is realized through a hydraulic pipeline, and the pipeline arrangement is complex;

d. powershift input pressure fluctuations can affect clutch control performance.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem of providing an electro-hydraulic control system and a tractor, and aims to solve the problems in the prior art.

The technical scheme for solving the technical problems is as follows:

an electro-hydraulic control system comprises a steering device, a multi-way valve device, a variable plunger pump and a steering priority valve, wherein an oil outlet of the variable plunger pump is communicated with an oil inlet of the steering priority valve through a pipeline, and two oil outlets of the steering priority valve are respectively communicated with an oil inlet of the steering device and an oil inlet of the multi-way valve device through pipelines.

The utility model has the beneficial effects that: in the using process, oil is sent to the steering priority valve through the variable displacement plunger pump, then is divided into two parts to be supplied to the steering device and the multi-way valve device respectively, and finally the steering device and the multi-way valve device complete corresponding actions; when the multi-way valve device runs, the flow of output oil is adjusted through the variable plunger pump, and different operation requirements of the steering device and the multi-way valve device are met; in addition, oil is preferentially provided for the steering device through the steering priority valve, and the oil is provided for the multi-way valve device after the oil requirement of the steering device is met. The utility model has compact structure and reasonable design, and reduces energy loss.

On the basis of the technical scheme, the utility model can be further improved as follows.

The variable plunger pump is characterized by further comprising a lubricating pump, a power gear shifting device and a transmission case filled with oil, wherein an oil inlet of the variable plunger pump is communicated with the transmission case through a pipeline; an oil inlet of the lubricating pump is communicated with a pipeline between the transmission case and the variable plunger pump through a pipeline, and an oil outlet of the lubricating pump is communicated with an oil inlet of the power gear shifting device through a pipeline.

The further scheme has the advantages that the lubricating pump is used for conveying oil to the power gear shifting device to complete gear shifting; in addition, the transmission case provides oil for the lubricating pump and the variable plunger pump at the same time, and pipelines are simplified.

And an oil inlet of the oil cylinder control device is communicated with a pipeline between the power gear shifting device and the lubricating pump through a pipeline.

The oil is respectively sent to the oil cylinder control device and the power gear shifting device through the lubricating pump, so that gear shifting action and oil cylinder control action are completed; at the moment, the lubricating pump can provide oil for the oil cylinder control device and the power gear shifting device simultaneously through a pipeline, and the pipeline is simplified.

The oil inlet of the LS pressure control valve is communicated with the second oil outlet of the variable plunger pump through a pipeline, and the oil outlet of the LS pressure control valve is communicated with a pipeline between the lubricating pump and the power gear shifting device through a pipeline; the LS pressure control valve, the steering device and the multi-way valve device are respectively in communication connection with the LS pressure controller.

The beneficial effect of adopting above-mentioned further scheme is that during the operation, LS pressure controller according to the variable plunger pump outlet pressure and the difference of the maximum operating pressure who turns to device and/or multiple unit valve device, output instruction adjustment LS pressure control valve control oil mouth pressure value, and then realize that the variable plunger pump provides the fluid flow as required, two kinds of operating modes of high economic nature and high maneuverability can be realized to the difference of pressure difference, the power loss is reduced by a wide margin to the high economic nature mode, and high maneuverability mode can realize turning to the little control of device and/or multiple unit valve device.

Further, the power gear shifting device comprises at least one gear shifting mechanism, and an oil inlet of each gear shifting mechanism is communicated with an oil outlet of the lubricating pump through a pipeline.

Adopt above-mentioned further scheme's beneficial effect to send fluid to gearshift through the lubricating pump, accomplish the action of shifting gears.

Furthermore, the power gear shifting device also comprises a power gear shifting controller, each gear shifting mechanism comprises a gear shifting valve and a wet clutch, an oil inlet of each gear shifting valve is communicated with an oil outlet of the lubricating pump through a pipeline, and an oil outlet of each gear shifting valve is communicated with the corresponding wet clutch through a pipeline; and each gear shifting valve is respectively in communication connection with the power gear shifting controller.

When the gear shifting mechanism operates, a gear shifting instruction of a corresponding gear shifting mechanism is input manually in advance through the power gear shifting controller, and the power gear shifting controller controls the gear shifting valve to realize the action of the wet clutch according to the corresponding instruction.

Further, the oil cylinder control device comprises an AMT oil cylinder control valve group and an energy accumulator, wherein an oil inlet of the AMT oil cylinder control valve group is communicated with a pipeline between the lubricating pump and the power gear shifting device through an energy accumulation pipeline; the energy accumulator is communicated with the energy storage pipeline through a pipeline.

The oil is sent to the AMT oil cylinder control valve group and the energy accumulator through the lubricating pump, so that the AMT oil cylinder control valve group can complete corresponding actions and the energy accumulator can be charged; when the lubricating pump supplies oil to the AMT oil cylinder control valve group, the operation of the oil is not enough, the energy accumulator can supply the prestored oil to the AMT oil cylinder control valve group to normally operate, and the working performance and the service life are ensured.

Further, the cylinder control device further comprises a cylinder controller, and the AMT cylinder control valve group is in communication connection with the cylinder controller.

When the further scheme is adopted, the beneficial effects are that when the hydraulic control system runs, a corresponding instruction is input into the oil cylinder controller through manual work or a built-in program, and the oil cylinder controller controls the AMT oil cylinder control valve group to act according to the corresponding instruction.

Furthermore, the AMT oil cylinder control valve group comprises at least one clutch control valve and at least one control clutch which corresponds to the clutch control valve one by one, the oil inlet of each clutch control valve is communicated with a pipeline between the lubricating pump and the power gear shifting device through a pipeline, and the oil outlet of each clutch control valve is communicated with the corresponding control clutch through a pipeline; and each clutch control valve is in communication connection with the oil cylinder controller respectively.

When the clutch control valve is operated, a corresponding instruction is input to the oil cylinder controller through manual work or a built-in program, and the oil cylinder controller controls the clutch control valve to control the action of the clutch according to the corresponding instruction.

Further, the AMT cylinder control valve group comprises at least one cylinder mechanism, wherein an oil inlet of each cylinder mechanism is communicated with a pipeline between the lubricating pump and the power gear shifting device through a pipeline, and the oil inlet of each cylinder mechanism is in communication connection with the cylinder controller.

When the further scheme is adopted, the method has the beneficial effects that when the method runs, corresponding parameters are manually input in advance through the oil cylinder controller, and the oil cylinder controller controls the oil cylinder mechanism to act according to the corresponding parameters; in the process, an oil pressure signal in the oil cylinder mechanism can be transmitted to the LS pressure control valve, the LS pressure control valve sends a corresponding pressure signal to the LS pressure controller, and the LS pressure controller controls the LS pressure control valve to adjust the oil output by the variable plunger pump according to the signal, so that excessive oil is prevented from being input, and energy consumption is saved.

Furthermore, a load sensing port on the steering device is communicated with the steering priority valve through a pipeline, and a steering pressure sensor is fixedly arranged on the pipeline between the load sensing port and the steering priority valve; and a load sensing port on the multi-way valve device is connected with a multi-way valve pressure sensor, and the steering pressure sensor and the multi-way valve pressure sensor are respectively in communication connection with the LS pressure controller.

The beneficial effect who adopts above-mentioned further scheme is that through turning to pressure sensor detection and turning to device actual operating pressure, detects the multiple unit valve device actual operating pressure through multiple unit valve pressure sensor simultaneously, and the two sends corresponding pressure signal for LS pressure controller respectively, and LS pressure controller controls LS pressure control valve according to this signal and adjusts variable plunger pump output flow, reduces the excessive fluid of input, practices thrift the energy consumption. When the opening degrees of the steering device and the multi-way valve device are unchanged, and when the actual working pressure of the steering device or the actual working pressure of the multi-way valve device is increased/decreased, the LS pressure controller controls the oil port pressure value by reducing/increasing the LS pressure, increases/decreases the output flow of the variable plunger pump, ensures that the difference value between the actual working pressure of the steering device or the actual working pressure of the multi-way valve device and the output pressure of the variable pump reaches a constant value, and realizes constant speed control. Under the constant power control mode, after the output power of the multi-way valve device reaches a constant power control point, when the actual working pressure of the multi-way valve device becomes large, the LS pressure controller controls the oil port pressure value by increasing the LS pressure, the output flow of the variable plunger pump is reduced, and the constant power control of the output power of the multi-way valve device is realized.

Furthermore, a variable pump outlet pressure sensor is fixedly installed on a pipeline between the variable plunger pump and the steering priority valve, and the variable pump outlet pressure sensor is in communication connection with the LS pressure controller.

The beneficial effect of adopting above-mentioned further scheme is that through the pressure sensor of variable pump outlet port detection variable plunger pump oil outlet department pressure of fluid to send corresponding signal to LS pressure controller, LS pressure controller adjusts the fluid volume of variable plunger pump output according to this signal control LS pressure control valve, avoids inputing excessive fluid, practices thrift the energy consumption, realizes more accurate control.

The oil inlet of the lubricating device is communicated with a pipeline between the lubricating pump and the power gear shifting device through a lubricating pipeline; an oil outlet of the steering device is communicated with the lubricating pipeline through a pipeline.

The lubricating device has the advantages that the lubricating pump is used for conveying oil to the lubricating device for lubricating operation, so that the pipeline is further simplified; in addition, the return oil in the steering device is supplied to the lubricating device through a corresponding pipeline for lubricating operation, so that resources are saved.

Furthermore, an overflow valve is fixedly installed on the lubricating pipeline.

The beneficial effect who adopts above-mentioned further scheme is through overflow valve holding valve front pressure for provide control pressure oil for LS pressure control valve, gear shift valve and AMT hydro-cylinder control valve group.

The oil inlet of the booster pump is communicated with a pipeline between the transmission case and the variable plunger pump through a pipeline, the first oil outlet of the booster pump is communicated with the oil inlet of the variable plunger pump through a pipeline, the second oil outlet of the booster pump is communicated with the oil inlet of the bypass control valve group through a pipeline, the first oil outlet of the bypass control valve group is communicated with the lubricating pipeline corresponding to the position between the overflow valve and the lubricating device through a pipeline, and the second oil outlet of the bypass control valve group is communicated with a pipeline between the booster pump and the bypass control valve group through a pipeline; and an oil inlet of the lubricating pump is communicated with a pipeline between the booster pump and the transmission case through a pipeline.

The variable plunger pump has the advantages that the booster pump is used for providing oil for the variable plunger pump, so that the oil inlet of the variable plunger pump is provided with enough oil, the oil absorption performance of the variable plunger pump is ensured, and the working efficiency of the variable plunger pump is improved; on the other hand, the booster pump supplies oil to the lubricating device, so that the lubricating device is ensured to obtain sufficient lubricating oil. When the variable plunger pump does not output oil, the bypass control valve group can not only enable part of oil to flow back to the oil inlet of the booster pump, but also can ensure that the pressure of the oil inlet of the variable plunger pump is not greater than a certain safety pressure.

Further, an oil suction pressure switch is fixedly installed at the communication position of the pipeline between the lubricating pump and the booster pump as well as the transmission case.

The beneficial effect who adopts above-mentioned further scheme is that provide fluid for whole hydraulic system through the transmission case to through the pressure of oil absorption pressure switch monitoring booster pump and lubricating pump oil inlet pipeline, when pressure was too big, need the manual work to maintain or maintain.

Further, the lubricating device comprises a lubricating control oil passage and a cooler, wherein the inlet of the cooler is communicated with the outlet of the lubricating pipeline, and the outlet of the cooler is communicated with the lubricating control oil passage through a pipeline; an oil outlet of the steering device is communicated with the lubricating control oil passage and the cooler through a pipeline.

The beneficial effect of adopting above-mentioned further scheme is that the fluid that comes by the lubricating pump is through the cooler cooling, and then send to the lubrication control oil duct and lubricate, guarantees lubricated effect.

Further, the lubricating device also comprises a lubricating bypass valve bank, wherein the inlet of the lubricating bypass valve bank is communicated with the position, close to the cooler, of the lubricating pipeline through a pipeline, and the outlet of the lubricating bypass valve bank is communicated with the pipeline between the cooler and the lubricating control oil passage through a pipeline; and the lubricating bypass valve group is also provided with a pressure relief opening.

The lubricating bypass valve group is used as a standby lubricating route, and when the cooler is blocked, oil enters the lubricating control oil passage through the lubricating bypass valve group, so that the normal operation of lubricating operation is ensured; and when the inlet pressure of the lubricating control oil passage is overlarge, partial oil is discharged through a pressure relief opening of the lubricating bypass valve group so as to perform pressure relief treatment, and the pressure inside the system is ensured to be normal.

The oil inlet of the safety valve is communicated with a pipeline between the steering priority valve and the multi-way valve device through a pipeline, the oil outlet of the multi-way valve device is communicated with an oil return pipeline, and the oil outlet of the safety valve is communicated with the oil return pipeline through a pipeline.

The adoption of the further scheme has the beneficial effects that when the pressure of the oil in the corresponding pipeline is less than the set pressure, all the oil enters the multi-way valve device; when the pressure of oil in the corresponding pipeline is greater than the set pressure, a part of oil enters the multi-way valve device to be used for normal operation of the multi-way valve device, and the other part of oil returns through the safety valve, so that overlarge pressure in the system is avoided, and the safety and the reliability are realized.

The utility model also relates to a tractor comprising the electro-hydraulic control system.

The tractor with the electro-hydraulic control system has the advantages that the tractor with the electro-hydraulic control system has the characteristics of high response speed, high control precision, convenience in operation and the like, and hydraulic pipelines are simplified; the device has a constant speed control function and can switch a high maneuverability or high economy mode; the working performance and the service life of the wet clutch are improved; the constant power function can ensure that the engine works in the best economic condition.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

In the drawings, the components represented by the respective reference numerals are listed below:

1. a multi-way valve pressure sensor; 2. a steering pressure sensor; 3. a steering priority valve; 4. an LS pressure controller; 5. a variable pump outlet pressure sensor; 6. an LS pressure control valve; 7. pressing oil filter; 8. a booster pump; 9. an oil suction pressure switch; 10. a transmission case; 11. an oil absorption filter; 12. a variable displacement plunger pump; 13. a lubrication pump; 14. a lubrication pump pressure filter; 15. a safety valve; 16. a multi-way valve device; 17. a shift valve; 18. a wet clutch; 19. a power shift controller; 20. lubricating the bypass valve bank; 21. a lubrication control oil passage; 22. a cooler; 23. an accumulator; 24. a power shift pressure sensor; 25. a one-way valve; 26. a four-wheel drive control clutch; 27. a cylinder controller; 28. an AMT oil cylinder control valve group; 29. a differential control clutch; 30. controlling the oil cylinder; 31. a PTO control clutch; 32. a PTO brake control clutch; 33. a bypass control valve bank; 34. an overflow valve; 35. a steering cylinder; 36. a full hydraulic steering gear.

Detailed Description

The principles and features of this invention are described in connection with the drawings and the detailed description of the utility model, which are set forth below as examples to illustrate the utility model and not to limit the scope of the utility model.

As shown in figure 1, the utility model provides an electro-hydraulic control system, which comprises a steering device, a multi-way valve device 16, a variable plunger pump 12 and a steering priority valve 3, wherein an oil outlet I of the variable plunger pump 12 is communicated with an oil inlet of the steering priority valve 3 through a pipeline, and two oil outlets of the steering priority valve 3 are respectively communicated with an oil inlet of the steering device and an oil inlet of the multi-way valve device 16 through pipelines. In the use process, the oil is sent to the steering priority valve 3 through the variable displacement plunger pump 12, then is divided into two parts to be respectively supplied to the steering device and the multi-way valve device 16, and finally the steering device and the multi-way valve device 16 complete corresponding actions; during operation, the flow of output oil is adjusted through the variable plunger pump 12, different operation requirements of the steering device and the multi-way valve device 16 are met, in addition, oil is preferentially provided for the steering device through the steering priority valve 3, and oil is provided for the multi-way valve device 16 after the oil requirement of the steering device is met. The utility model has compact structure and reasonable design, and reduces energy loss.

Example 1

On the basis of the structure, the variable plunger pump further comprises a lubricating pump 13, a power gear shifting device and a transmission case 10 filled with oil, wherein an oil inlet of the variable plunger pump 12 is communicated with the transmission case 10 through a pipeline; an oil inlet of the lubricating pump 13 is communicated with a pipeline between the transmission case 10 and the variable plunger pump 12 through a pipeline, and an oil outlet of the lubricating pump is communicated with an oil inlet of the power gear shifting device through a pipeline. During operation, oil is sent to the power gear shifting device through the lubricating pump 13, and gear shifting action is completed.

Example 2

On the basis of the structure, the oil cylinder control device is further included in the embodiment, and an oil inlet of the oil cylinder control device is communicated with a pipeline between the power gear shifting device and the lubricating pump 13 through the pipeline. When the gear shifting device runs, oil is simultaneously sent to the oil cylinder control device and the power gear shifting device through the lubricating pump 13, and gear shifting action and oil cylinder control action are completed; at this moment, the lubricating pump 13 can provide oil for the oil cylinder control device and the power gear shifting device simultaneously through a pipeline, and the pipeline is simplified.

Example 3

On the basis of the above embodiments, the present embodiment further includes an LS pressure controller 4 and an LS pressure control valve 6, a control oil port of the LS pressure control valve 6 is communicated with a variable control oil cylinder communicated with the second oil outlet of the variable plunger pump 12 through a pipeline, and an oil inlet thereof is communicated with a pipeline between the lubrication pump 13 and the power shift device through a pipeline; the LS pressure control valve 6, the steering device and the multi-way valve device 16 are each connected in communication with the LS pressure controller 4. When the hydraulic control system runs, the LS pressure controller 4 outputs an instruction to adjust the pressure value of the control oil port of the LS pressure control valve 6 according to the difference value between the pressure of the oil outlet of the variable plunger pump 12 and the maximum working pressure of the steering device and/or the multi-way valve device 16, so that the variable plunger pump 12 can provide oil flow according to needs, two running modes of high economy and high maneuverability can be realized through the difference of the pressure difference values, the power loss is greatly reduced through the high economy mode, and the micro control of the steering device and/or the multi-way valve device 16 can be realized through the high maneuverability mode.

When the scheme is based on the scheme of the embodiment 1, namely the oil cylinder control device and the power gear shifting device exist at the same time, the lubricating pump 13 supplies oil to the oil cylinder control device and the power gear shifting device at the same time, and an oil inlet of the oil cylinder control device is communicated with a pipeline between the LS pressure control valve 6 and the power gear shifting device; when the above-described scheme is not based on the mode of embodiment 1, that is, the cylinder control device and the power shift device are alternatively present, the oil is supplied to the cylinder control device or the power shift device through the lubricating pump 13.

Example 4

On the basis of embodiment 3, in this embodiment, the power shift device includes at least one shift mechanism, and an oil inlet of each shift mechanism is communicated with an oil outlet of the lubrication pump 13 through a pipeline. During operation, oil is sent to the gear shifting mechanism through the lubricating pump 13, and gear shifting action is completed.

Example 5

On the basis of embodiment 4, in this embodiment, the power shift device further includes a power shift controller 19, each shift mechanism includes a shift valve 17 and a wet clutch 18, an oil inlet of each shift valve 17 is communicated with an oil outlet of the lubrication pump 13 through a pipeline, and a control oil port thereof is communicated with the corresponding wet clutch 18 through a pipeline; each of the selector valves 17 is in communication with a respective power shift control 19. During operation, a command corresponding to the gear shifting mechanism is manually input in advance through the power gear shifting controller 19, and the power gear shifting controller 19 controls the gear shifting valve 17 according to the corresponding command to realize the action of the wet clutch 18

Example 6

On the basis of embodiment 4 or embodiment 5, preferably, in this embodiment, the power shift device includes a plurality of shift mechanisms distributed in parallel, oil inlets of a plurality of shift valves 17 in the plurality of shift mechanisms are respectively communicated with an oil inlet pipeline through a pipeline, and an oil inlet end of the oil inlet pipeline is communicated with an oil outlet of the lubricating pump 13 through a pipeline; meanwhile, oil outlets of the gear shifting valves 17 in the gear shifting mechanisms are communicated with an oil return pipeline through pipelines respectively, and the oil return pipeline is communicated with an oil return box, so that the oil is quickly recovered, the oil is recycled, and resources are saved.

In addition, a plurality of shift valves 17 in the plurality of shift mechanisms are respectively connected with the power shift controller 19 in a communication mode, and the control of the plurality of shift valves 17 is realized through the power shift controller 19.

Example 7

On the basis of embodiment 3, in this embodiment, the cylinder control device includes an AMT cylinder control valve group 28 and an accumulator 23, and an oil inlet of the AMT cylinder control valve group 28 is communicated with a pipeline between the lubrication pump 13 and the power shift device through an energy accumulation pipeline; the accumulator 23 is in communication with the accumulator line via a line. When the hydraulic system runs, oil is sent to the AMT cylinder control valve group 28 and the energy accumulator through the lubricating pump 13, so that the AMT cylinder control valve group 28 can complete corresponding actions and the energy accumulator 23 can be charged; in addition, when the lubrication pump 13 supplies the oil to the AMT cylinder control valve group 28, there is an excess part of the oil when the operation is satisfied, and the excess part of the oil is stored in the accumulator 23; when the oil supplied to the AMT cylinder control valve set 28 by the lubricating pump 13 is not enough to meet the operation requirement, the accumulator 23 can supply the pre-stored oil to the AMT cylinder control valve set to operate normally, so that the working performance and the service life of each component are ensured.

Example 8

On the basis of embodiment 7, in this embodiment, the cylinder control device further includes a cylinder controller 27, and the AMT cylinder control valve group 28 is in communication connection with the cylinder controller 27. When the AMT hydraulic control system operates, a corresponding instruction is input into the cylinder controller 27 through manual work or a built-in program, and the cylinder controller 27 controls the AMT cylinder control valve group 28 to act according to the corresponding instruction

Example 9

On the basis of embodiment 8, in this embodiment, a power shift pressure sensor 24 is fixedly installed on a pipeline through which the accumulator 23 communicates with the AMT cylinder control valve set 28, and the power shift pressure sensor 24 is in communication connection with the cylinder controller 27 and the power shift controller 19, respectively. During operation, the power gear shifting pressure sensor 24 detects the oil pressure at the energy accumulator 23 and sends a corresponding pressure signal to the oil cylinder controller 27, the oil cylinder controller 27 receives the corresponding pressure signal and compares the pressure signal with a pressure threshold value input in advance, and the two pressure values are analyzed and judged; when the pressure sensor 24 is not less than the pressure threshold value through power shifting, the oil cylinder controller 27 receives a signal sent by an operator operating button and executes a corresponding action, so that the AMT oil cylinder control valve group 28 is ensured to normally operate; when the pressure sensor 24 is less than the pressure threshold value through power shifting, the cylinder controller 27 receives a signal sent by an operator operating button, but the cylinder controller 27 does not execute corresponding actions and needs to be maintained by an operator, so that the normal operation of the AMT cylinder control valve group 28 is ensured.

Example 10

On the basis of embodiment 8 or embodiment 9, in this embodiment, the AMT cylinder control valve set 28 includes at least one clutch control valve and at least one control clutch corresponding to the clutch control valve one to one, an oil inlet of each clutch control valve is communicated with a pipeline between the lubrication pump 13 and the power shift device through a pipeline, and an oil outlet thereof is communicated with the corresponding control clutch through a pipeline; each clutch control valve is in communication with a respective cylinder controller 27. When the clutch is operated, a corresponding instruction is input into the oil cylinder controller 27 in advance through a manual or built-in program, and the oil cylinder controller 27 controls the clutch control valve to control the action of the clutch according to the corresponding instruction

Example 11

On the basis of the embodiment 10, in this embodiment, the AMT cylinder control valve set 28 includes a four-wheel drive control clutch 26 and a four-wheel drive clutch control valve, an oil inlet of the four-wheel drive clutch control valve is communicated with a pipeline between the lubrication pump 13 and the power shift device through a pipeline, and an oil outlet of the four-wheel drive clutch control valve is communicated with the four-wheel drive control clutch 26 through a pipeline; the four-wheel drive clutch control valve is in communication connection with the cylinder controller 27.

Example 12

On the basis of embodiment 10 or embodiment 11, in this embodiment, the AMT cylinder control valve set 28 further includes a differential control clutch 29 and a differential clutch control valve, an oil inlet of the differential clutch control valve is communicated with a pipeline between the lubrication pump 13 and the power shift device through a pipeline, and an oil outlet of the differential clutch control valve is communicated with the differential control clutch 29 through a pipeline; the differential clutch control valve is in communication with the cylinder controller 27.

Example 13

On the basis of any one of embodiments 10 to 12, in this embodiment, the AMT cylinder control valve set 28 further includes a PTO control clutch 31 and a PTO control valve, an oil inlet of the PTO control valve is communicated with a pipeline between the lubrication pump 13 and the power shift device through a pipeline, and an oil outlet thereof is communicated with the PTO control clutch 31 through a pipeline; the PTO control valve is in communication with the cylinder controller 27.

Example 14

On the basis of any one of embodiment 10 to embodiment 13, in this embodiment, the AMT cylinder control valve set 28 further includes a PTO brake control clutch 32 and a PTO brake control valve, an oil inlet of the PTO brake control valve is communicated with a pipeline between the lubrication pump 13 and the power shift device through a pipeline, and an oil outlet thereof is communicated with the PTO brake control clutch 32 through a pipeline; the PTO brake control valve is in communication with the cylinder controller 27.

The oil inlets of the four-wheel drive clutch control valve, the differential clutch control valve, the PTO control valve and the PTO brake control valve can be respectively and directly communicated with the pipeline between the lubricating pump 13 and the power gear shifting device through pipelines, or can be firstly communicated with an oil supply pipeline, and the oil inlet end of the oil supply pipeline is communicated with the pipeline between the lubricating pump 13 and the power gear shifting device, preferably the latter, so that the pipelines are simplified.

In addition, the oil outlets of the four-wheel drive clutch control valve, the differential clutch control valve, the PTO control valve and the PTO brake control valve can be respectively and directly communicated with the oil return tank through an oil return pipeline, or can be communicated with the oil return pipeline firstly, and the oil outlet of the oil return pipeline is communicated with the oil return tank.

Example 15

On the basis of any one of embodiments 10 to 14, in this embodiment, the AMT cylinder control valve set 28 includes at least one cylinder mechanism, an oil inlet of each cylinder mechanism is communicated with a pipeline between the lubrication pump 13 and the power shift device through a pipeline, and an oil return port thereof is communicated with an oil return tank; the cylinder mechanism is in communication connection with a cylinder controller 27. When the device operates, corresponding parameters are manually input in advance through the oil cylinder controller 27, and the oil cylinder controller 27 controls the oil cylinder mechanism to act according to the corresponding parameters; in the process, the oil pressure signal in the oil cylinder mechanism can be transmitted to the LS pressure control valve 6, the LS pressure control valve 6 sends the corresponding pressure signal to the LS pressure controller 4, and the LS pressure controller 4 controls the LS pressure control valve 6 to adjust the oil amount output by the variable displacement piston pump 12 according to the signal, so that excessive oil is prevented from being input, and energy consumption is saved.

Example 16

On the basis of the embodiment 15, in the embodiment, each oil cylinder mechanism comprises a control oil cylinder 30 and two oil cylinder control valves, wherein an oil inlet of one oil cylinder control valve is communicated with a pipeline between the lubricating pump 13 and the power gear shifting device through a pipeline, and an oil outlet of the one oil cylinder control valve is communicated with an oil inlet of the control oil cylinder 30; the oil outlet of the control oil cylinder 30 is communicated with the oil inlet of the other oil cylinder control valve through a pipeline, and the oil outlet of the other oil cylinder control valve is communicated with the oil return tank through a pipeline.

In addition, the two cylinder control valves are respectively connected with the cylinder controller 27 in communication.

When the control system operates, a corresponding instruction is input into the oil cylinder controller 27 through manual work or a built-in program, and the oil cylinder controller 27 controls the oil cylinder control valve according to the corresponding instruction, so that the oil cylinder control valve controls the oil cylinder 30 to act.

In addition to the above manner, the oil inlet of one of the cylinder control valves is communicated with the oil supply pipeline through a pipeline, and the oil outlet is communicated with the oil inlet of the control cylinder 30; the oil outlet of the control oil cylinder 30 is communicated with the oil inlet of the other oil cylinder control valve through a pipeline, and the oil outlet of the other oil cylinder control valve is communicated with the oil return pipeline through a pipeline.

The control cylinders 30 can realize gear shifting, and one control cylinder 30 controls one gear to shift upwards and shift downwards. The number of the control cylinders 30 may be one or more as necessary.

Example 17

On the basis of embodiment 15 or embodiment 16, preferably, in this embodiment, the number of the cylinder mechanisms is two, and the two cylinder mechanisms are arranged in parallel.

The above-mentioned manual input of the corresponding parameters through the cylinder controller 27 means which control cylinder 30 and the corresponding two cylinder control valves are operated.

Example 18

In addition to the above embodiments, in the present embodiment, the load sensing port of the steering device is communicated with the steering priority valve 3 through a pipeline, and the steering pressure sensor 2 is fixedly mounted on the pipeline between the load sensing port and the steering priority valve; the load sensing port on the multi-way valve device 16 is connected with a multi-way valve pressure sensor 1, and the steering pressure sensor 2 and the multi-way valve pressure sensor 1 are respectively in communication connection with an LS pressure controller 4. When the hydraulic control system runs, the actual working pressure of the steering device is detected through the steering pressure sensor 2, the actual working pressure of the multi-way valve device 16 is detected through the multi-way valve pressure sensor 1, corresponding pressure signals are respectively sent to the LS pressure controller 4, the LS pressure controller 4 controls the LS pressure control valve 6 to adjust the output flow of the variable displacement plunger pump 12 according to the signals, the input of excessive oil is reduced, and the energy consumption is saved.

When the opening degrees of the steering device and the multi-way valve device 16 are not changed, and the actual working pressure of the steering device or the actual working pressure of the multi-way valve device 16 is increased/decreased, the LS pressure controller 4 controls the oil port pressure value by reducing/increasing the LS pressure control valve 6, increases/decreases the output flow of the variable plunger pump 12, ensures that the difference value between the actual working pressure of the steering device or the actual working pressure of the multi-way valve device 16 and the pressure at the oil outlet of the variable plunger pump 12 reaches a constant value, and realizes constant speed control. Under the constant power control mode, after the output power of the multi-way valve device 16 reaches a constant power control point, when the actual working pressure of the multi-way valve device 16 becomes large, the LS pressure controller 4 controls the pressure value of the oil port by increasing the LS pressure control valve 6, the output flow of the variable plunger pump is reduced, and the constant power control of the output power of the multi-way valve device 16 is realized.

Example 19

On the basis of the embodiment 18, in the embodiment, the variable displacement pump outlet pressure sensor 5 is fixedly installed on the pipeline between the variable displacement plunger pump 12 and the steering priority valve 3, and the variable displacement pump outlet pressure sensor 5 is in communication connection with the LS pressure controller 4. When the variable plunger pump is in operation, the pressure of oil at the oil outlet of the variable plunger pump 12 is detected through the variable pump outlet pressure sensor 5, a corresponding signal is sent to the LS pressure controller 4, the LS pressure controller 4 controls the LS pressure control valve 6 to adjust the oil output by the variable plunger pump 12 according to the signal, excessive oil is prevented from being input, energy consumption is saved, and more accurate control is achieved.

Example 20

On the basis of the above embodiments, the present embodiment further includes a lubricating device, an oil inlet of the lubricating device is communicated with a pipeline between the lubricating pump 13 and the power gear shifting device through a lubricating pipeline; an oil outlet of the steering device is communicated with the lubricating pipeline through a pipeline. During operation, the lubricating pump 13 is used for sending oil to the lubricating device for lubricating operation, so that the pipeline is further simplified; in addition, partial oil in the steering device is supplied to the lubricating device through the corresponding pipeline for lubricating operation, so that resources are saved.

Example 21

In addition to embodiment 20, in this embodiment, a relief valve 34 is fixedly attached to the lubrication line. In operation, the pre-valve pressure is maintained by the relief valve 34 for providing control pressure oil to the LS pressure control valve 6, the shift valve 17 and the AMT cylinder control valve block 28.

Preferably, in this embodiment, a pipeline close to an oil outlet of the lubricating pump 13 is fixedly provided with a lubricating pump pressure filter 14, and the lubricating pump pressure filter 14 filters oil to remove impurities in the oil, thereby ensuring the working performance of each device.

Example 22

On the basis of the embodiment 21, the present embodiment further includes a booster pump 8 and a bypass control valve group 33, an oil inlet of the booster pump 8 is communicated with a pipeline between the transmission case 10 and the variable plunger pump 12 through a pipeline, an oil outlet one of the booster pump 8 is communicated with an oil inlet of the variable plunger pump 12 through a pipeline, an oil outlet two of the booster pump is communicated with an oil inlet of the bypass control valve group 33 through a pipeline, an oil outlet one of the bypass control valve group 33 is communicated with a position between the lubricating device and the overflow valve 34 corresponding to the lubricating pipeline through a pipeline, and an oil outlet two of the bypass control valve group 33 is communicated with a pipeline between the booster pump 8 and the bypass control valve group 33 through a pipeline; an oil inlet of the lubricating pump 13 is communicated with a pipeline between the booster pump 8 and the transmission case 10 through a pipeline. When the variable plunger pump 12 operates, the booster pump 8 supplies oil to the variable plunger pump 12, so that the oil inlet of the variable plunger pump 12 has enough oil, the oil absorption performance of the variable plunger pump 12 is ensured, and the working efficiency of the variable plunger pump is improved; on the other hand, the booster pump 8 supplies oil to the lubricating device, so that the lubricating device is ensured to obtain sufficient lubricating oil. When the variable plunger pump 12 does not output oil, the bypass control valve group 33 can not only return part of the oil to the oil inlet of the booster pump 8, but also ensure that the pressure of the oil inlet of the variable plunger pump 12 is not greater than the set safety pressure.

Preferably, in this embodiment, the hydraulic control system further includes a check valve 25, a first pipeline is a pipeline between the booster pump 8 and a first oil outlet of the bypass control valve group 33, and a second oil outlet of the bypass control valve group 33 is communicated with the first pipeline through a second pipeline; an oil inlet of the one-way valve 25 is communicated with the second pipeline through a pipeline, and an oil outlet of the one-way valve is communicated with a pipeline between an oil inlet of the booster pump 8 and the transmission case 10 through a pipeline. When the variable plunger pump 12 does not output oil, the check valve 25 can not only return part of the oil to the oil inlet of the booster pump 8, but also ensure that the pressure of the oil inlet of the variable plunger pump 12 is not greater than the set safety pressure.

Example 23

On the basis of the embodiment 22, the bypass control valve group 33 is composed of two check valves, oil inlets of the two check valves are communicated through a pipeline, and oil outlets of the booster pump 8 are communicated with the pipeline communicated between the two check valves through a pipeline; oil outlets of the two check valves are respectively communicated with a lubricating pipeline and a pipeline between the booster pump 8 and the bypass control valve group 33.

Based on the scheme, when a large amount of lubricating liquid is needed in the combination of the wet clutch 18, the flow rate of the oil passing through the left check valve is large, so that the working performance and the service life of the wet clutch 18 are ensured; when the wet clutch 18 needs a small amount of lubricating liquid, the flow rate of the left check valve passing through the oil liquid is small, so that the working performance and the service life of the wet clutch 18 are ensured; in a low-temperature environment, part of oil can flow through the right check valve, so that the oil suction pressure of the lubricating pump 13 is higher, and the working efficiency of the lubricating pump 13 is improved.

Example 24

On the basis of the embodiment 22, in the embodiment, the oil suction pressure switch 9 is fixedly installed at the communication part of the pipelines between the lubrication pump 13 and the booster pump 8 and the transmission case 10. In operation, oil is provided to the whole hydraulic system through the transmission case 10, and the pressure of the oil inlet pipeline is switched between the booster pump 8 and the lubricating pump 13 through oil absorption pressure.

Preferably, the oil suction pressure switch 9 is in communication connection with an alarm, when the pressure inside the transmission case 10 is too high, the oil suction pressure switch 9 transmits a signal to the alarm, and the alarm gives an alarm to remind a worker of maintenance or repair in time.

Example 25

On the basis of embodiment 24, in this embodiment, fixed mounting has the oil absorption filter 11 on the pipeline between transmission 10 and the oil absorption pressure switch 9, carries out preliminary filtration processing to fluid through oil absorption filter 11 in the operation process, gets rid of most impurity in the fluid, avoids impurity to influence the working property of each part.

Example 26

On the basis of the embodiment 24 or the embodiment 25, in this embodiment, the pressure oil filter 7 is fixedly installed on the pipeline between the booster pump 8 and the bypass control valve group 33, and during the operation, the pressure oil filter 7 is used to further filter the oil liquid, so as to remove impurities in the oil liquid and further ensure the working performance of each component.

Example 27

On the basis of any one of embodiments 20 to 26, in the present embodiment, the lubricating device includes the lubrication control oil passage 21 and the cooler 22, an inlet of the cooler 22 communicates with an outlet of the lubrication line, and an outlet thereof communicates with the lubrication control oil passage 21 through a line; the oil outlet of the steering device is communicated with a pipeline between the lubrication control oil passage 21 and the cooler 22 through a pipeline. During operation, oil delivered by the lubricating pump 13 is cooled by the cooler 22 and then delivered to the lubricating control oil passage 21 for lubrication, so that the lubricating effect is ensured.

The above-described lubrication control oil passage 21 refers to an oil passage that supplies oil to a component that needs to be lubricated.

Example 28

On the basis of embodiment 27, in this embodiment, the lubricating apparatus further includes a lubricating bypass valve group 20, an inlet of the lubricating bypass valve group 20 is communicated with a position of the lubricating pipeline close to the cooler 22 through a pipeline, and an outlet thereof is communicated with a pipeline between the cooler 22 and the lubricating control oil passage 21 through a pipeline; the lubricating bypass valve set 20 is also provided with a pressure relief port. In the operation process, the lubricating bypass valve group 20 is used as a standby lubricating route, and when the cooler 22 is blocked, oil enters the lubricating control oil passage 21 through the lubricating bypass valve group 20, so that the normal operation of the lubricating operation is ensured; moreover, when the inlet pressure of the lubrication control oil passage 20 is too high, part of oil is discharged through a pressure relief port of the lubrication bypass valve group 20 to perform pressure relief processing, so that the pressure inside the system is ensured to be normal.

Example 29

On the basis of the embodiment 28, in this embodiment, the lubricating bypass valve set 20 is composed of two check valves, wherein an inlet and an outlet of one check valve are respectively communicated with the lubricating pipeline at a position close to the cooler 22 through a pipeline, and an outlet of one check valve is communicated with the pipeline between the cooler 22 and the lubricating control oil passage 21 through a pipeline; the inlet of the other one-way valve is communicated with the pipeline between one-way valve and the lubricating control oil channel 21 through a pipeline, and the outlet of the other one-way valve is the pressure relief port and is communicated with an oil return tank.

Example 30

On the basis of the above embodiments, the present embodiment further includes a safety valve 15, an oil inlet of the safety valve 15 is communicated with a pipeline between the steering priority valve 3 and the multi-way valve device 16 through a pipeline, an oil outlet of the multi-way valve device 16 is communicated with an oil return pipeline, and an oil outlet of the safety valve 15 is communicated with the oil return pipeline through a pipeline. When the pressure of the oil in the corresponding pipeline is lower than the set pressure during operation, all the oil enters the multi-way valve device 16; when the pressure of the oil in the corresponding pipeline is greater than the set pressure, a part of the oil enters the multi-way valve device 16 at the moment so that the multi-way valve device 16 can normally operate, and the other part of the oil returns through the safety valve 15, so that overlarge pressure in the system is avoided, and the safety and reliability are realized.

In addition, the oil outlet end of the oil return pipeline is communicated with an oil return tank.

It should be noted that, the oil recovery of the above components can be respectively recovered by an oil return tank, or directly recovered into the transmission case 10, preferably the latter, which simplifies the structure and reduces the cost.

Example 31

On the basis of the above embodiments, in this embodiment, the steering apparatus includes the full hydraulic steering gear 36 and the steering cylinder 35, the full hydraulic steering gear 36 is in transmission connection with the steering wheel, an oil inlet thereof is communicated with one of the oil outlets of the steering priority valve 3, an oil outlet thereof is communicated with the pipeline between the lubrication control oil passage 21 and the cooler 22, and a load sensing port thereof is communicated with the steering priority valve 3 through the pipeline; in addition, an oil inlet and an oil outlet of the steering oil cylinder 35 are respectively communicated with a full hydraulic steering gear 36. When the tractor is operated, a driver rotates a steering wheel to enable an L/R working oil port of the full hydraulic steering gear 36 to output pressure oil, and the steering oil cylinder 35 is driven to move left/right to achieve steering of the tractor.

In addition, the port P shown in fig. 1 is an oil inlet, the port T is an oil return port, the port LS is a load sensing port, the port L is a left-turn working oil port, and the port R is a right-turn working oil port.

Example 32

In addition to the above embodiments, in the present embodiment, the multiple-way valve device 16 is used to connect the actuators, and the number of the connected actuators may be one or more.

When the number of the actuating mechanisms is one, the oil pressure required by the actuating mechanisms is detected through the multi-way valve pressure sensor 1, the corresponding pressure signals are sent to the LS pressure controller 4, meanwhile, the pressure signals are also sent to the LS pressure controller 4 through the variable pump outlet pressure sensor 5, the LS pressure controller 4 controls the LS pressure control valve 6 to adjust the oil quantity output by the variable plunger pump 12 according to the pressure difference value obtained by the two signals, the input of excessive oil is avoided, the energy consumption is saved, and more accurate control is realized.

When the number of the actuating mechanisms is multiple, the number of the multi-way valve pressure sensors 1 is multiple at the moment, the multi-way valve pressure sensors are respectively in one-to-one correspondence with the actuating mechanisms and are respectively used for detecting the oil pressure force required by the operation of the actuating mechanisms, the corresponding pressure signals are sent to the LS pressure controller 4, the LS pressure controller 4 judges the maximum oil pressure force required by the operation of the actuating mechanisms and the number of the actuating mechanisms working simultaneously according to the signals, the difference value between the maximum pressure and the pressure detected by the variable pump outlet pressure sensor 5 is obtained, the oil amount output by the variable plunger pump 12 is adjusted by controlling the control oil port pressure value of the LS pressure control valve 6, the input of excessive oil is avoided, the energy consumption is saved, and more accurate control is realized. Under the condition that the pressure difference value is the same, the more the number of the actuating mechanisms working simultaneously is, the smaller the pressure value of the control oil port of the LS pressure control valve 6 is, and the larger the output flow of the variable displacement plunger pump 12 is.

Preferably, in this embodiment, the number of the actuators is four, and the multiplex valve device 16 is provided with four ports connected to the four actuators, which are respectively S _1, S _2, S _3 and S _ 4.

Example 33

On the basis of the above embodiments, the present embodiment further provides a tractor including the above-described electro-hydraulic control system. The embodiment provides a tractor with the electro-hydraulic control system, which has the characteristics of high response speed, high control precision, convenience in operation and the like, and simplifies a hydraulic pipeline; the device has a constant speed control function and can switch a high maneuverability or high economy mode; the operating performance and the service life of the wet clutch 18 are improved; the constant power function can ensure that the engine works in the best economic condition.

The operation principle of the utility model is as follows:

the booster pump 8 sucks the oil which passes through the oil suction filter 11 from the transmission case 10, the oil passes through the oil pressing filter 7, part of the oil enters the variable displacement plunger pump 12, and the rest of the oil flows into the bypass control valve group 33. The hydraulic oil supplied by the variable displacement piston pump 12 passes through the steering priority valve 3 and is then delivered to the steering device and the multi-way valve device 16 according to different priority levels.

The oil supplied by the lubricating pump 13 firstly passes through the lubricating pump pressure filter 14, power gear-shifting control oil is output under the action of the overflow valve 34, the rest part of the oil flows out of the converging bypass control valve group 33 and is conveyed to the cooler 22 together with the oil return of the full hydraulic steering gear 36, and the oil are conveyed to the lubricating device and finally directly returned to the transmission case 10.

The LS pressure control valve 6 is used for controlling the pressure value of a variable control oil port on the variable plunger pump 12 and realizing the adjustment of the displacement of the variable plunger pump 12.

The system sets parameters: standby LS pressure P1, steering LS pressure P2, LS pressure controller 4 calculating LS pressures PX and PY, adjustable constant speed control pressure difference delta P, constant power control pressure PP and system maximum working pressure Pmax, and the specific operation principle is as follows:

(1) when the tractor hydraulic system is in a standby state, the LS pressure controller 4 controls the output pressure of the LS pressure control valve 6 to be P1, the variable displacement plunger pump 12 is in a small flow output state, and output oil is used for lubricating and leaking the variable displacement plunger pump 12.

(2) Only the steering device works, and the following two control principles are adopted:

A. the steering pressure sensor 2 transmits the working pressure to the LS pressure controller 4, the LS pressure controller 4 outputs a control signal, the LS pressure control valve 6 controls the pressure of an oil port to be P2, and the variable displacement plunger pump 12 outputs constant oil required by a steering system. The control principle ensures that the steering flow is sufficient and safer.

B. The steering pressure sensor 2 transmits a working pressure signal to the LS pressure controller 4, the variable displacement pump outlet pressure sensor 5 transmits a pressure signal to the LS pressure controller 4, the LS pressure controller 4 outputs a control signal according to a pressure difference value delta P3 obtained by the two pressure signals, the LS pressure control valve 6 is controlled to control the pressure of an oil port, and then the variable displacement plunger pump 12 is adjusted to output oil liquid required by the steering device. The faster/slower the steering device is turned, the more/less flow the variable displacement pump 12 will output in order to ensure that the pressure differential ap 3 is constant. The control principle variable plunger pump 12 provides flow according to the requirement of the steering device, and the system is more energy-saving.

(3) Only the multi-way valve device 16 is operated, a driver operates a control knob for controlling the multi-way valve device 16, the LS pressure controller 4 outputs control signals S _1, S _2, S _3 and S _4, and the multi-way valve device 16 executes corresponding actions after obtaining the control signals S _1, S _2, S _3 and S _ 4. The LS pressure controller 4 calculates the pressure difference between the multi-way valve pressure sensor 1 and the variable pump outlet pressure sensor 5 in real time and the number of the actuating mechanisms, outputs control signals, controls the LS pressure control valve 6 to control the pressure of the oil port, and then adjusts the variable plunger pump 12 to output oil required by the multi-way valve device 16. The multi-way valve device 16 is electrically controlled, and if the multi-way valve device 16 is manually operated, the transmission of the output control signals S _1, S _2, S _3 and S _4 is realized by a mechanical pull rod or a flexible shaft, but not by the LS pressure controller 4.

(4) The steering device and the multi-way valve device 16 work simultaneously, assuming that the multi-way valve device 16 is in a normal working state, the pressure of the LS pressure control valve 6 is PY at the moment, the steering device starts to work, the steering pressure sensor 2 transmits the steering working pressure to the LS pressure controller 4, the LS pressure controller 4 calculates and outputs a control signal corresponding to the total flow required by the steering device and the multi-way valve device 16, and if the pressure of the LS pressure control valve 6 is P2+ PY, the variable displacement plunger pump 12 outputs a constant flow required by the steering device and a real-time variable flow required by the multi-way valve device 16; if the pressure of the LS pressure control valve 6 is PX + PY, the variable displacement plunger pump 12 outputs the oil flow which is the real-time variable flow required by the steering device + the real-time variable flow required by the multi-way valve device 16.

Assuming that the steering device is in a normal working state, at this time, the pressure of the LS pressure control valve 6 is PX, a driver operates a control knob of the multi-way valve device 16, the LS pressure controller 4 outputs control signals S _1, S _2, S _3 and S _4, the multi-way valve device 16 receives the control signals S _1, S _2, S _3 and S _4 and executes corresponding actions, the LS pressure controller 4 calculates the difference between the pressures detected by the multi-way valve pressure sensor 1 and the variable pump outlet pressure sensor 5 in real time and the number of execution mechanisms, and outputs control signals to control the pressure of the oil port of the LS pressure control valve 6 to be PX + PY, thereby adjusting the oil flow rate required by the variable displacement plunger pump 12 to output the steering device and the multi-way valve device 16. (5) The multi-way valve device 16 works in a single connection (only one actuating mechanism), when the load becomes larger/smaller, the pressure difference value delta P1 returned by the multi-way valve pressure sensor 1 and the variable pump outlet pressure sensor 5 is smaller/larger than the constant speed control pressure difference delta P set by the system, the LS pressure controller 4 calculates and outputs the control signal of the LS pressure control valve 6 according to the absolute value of the difference value delta P1 and the delta P, and the purpose of constant speed control is achieved.

When the constant power control switch of the variable plunger pump 12 is turned on, and the working pressure is brought to the constant power control pressure PP, the output pressure of the variable plunger pump 12 is continuously increased, the control pressure of the LS pressure control valve 6 is increased, so that the output flow of the variable plunger pump 12 is reduced, otherwise, the control pressure of the LS pressure control valve 6 is reduced, so that the output flow of the variable plunger pump 12 is increased.

(6) The multi-way valve device 16 works in a multi-way mode (a plurality of actuating mechanisms work simultaneously), when the maximum load is increased, the pressure difference delta P2 returned by the multi-way valve pressure sensor 1 and the variable pump outlet pressure sensor 5 is smaller than the constant speed control pressure difference delta P set by the system, or when the maximum load is decreased, the pressure difference delta P2 returned by the multi-way valve pressure sensor 1 and the variable pump outlet pressure sensor 5 is larger than the constant speed control pressure difference delta P set by the system, the LS pressure controller 4 calculates and outputs the control signal of the LS pressure control valve 6 according to the absolute value of the difference between the delta P2 and the delta P, and the multi-way valve device achieves a multi-way compound action.

When the total flow required by the multiplex valve arrangement 16 reaches the maximum value that the variable displacement piston pump 12 can provide to the multiplex valve arrangement 16, the actuators of the multiplex valve arrangement 16 distribute all the oil flows proportionally according to the opening area. If the working pressure value of the multi-way valve device 16 reaches the maximum working pressure Pmax of the system, the LS pressure controller 4 controls the LS pressure control valve 6 to control the pressure to be maximum, so that the variable displacement plunger pump 12 reaches the minimum displacement.

(7) According to the requirement of the multi-way valve device 16 on the speed regulation performance, the constant speed control pressure difference delta P set by the system can be adjusted. When the constant-speed control pressure difference delta P is small, the speed regulation performance is weak, and the power loss is small, otherwise, the speed regulation performance is good, and the power loss is large.

The electronic components and the corresponding controllers may be connected by wireless communication or by wires.

In addition, the electronic components according to the present invention are conventionally used, and the above-described components are electrically connected to each other, and the control circuit between the components is conventionally used.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. An electro-hydraulic control system, characterized by: the hydraulic steering control system comprises a steering device, a multi-way valve device (16), a variable plunger pump (12) and a steering priority valve (3), wherein an oil outlet I of the variable plunger pump (12) is communicated with an oil inlet of the steering priority valve (3) through a pipeline, and two oil outlets of the steering priority valve (3) are respectively communicated with an oil inlet of the steering device and an oil inlet of the multi-way valve device (16) through pipelines.

2. The electro-hydraulic control system of claim 1, wherein: the variable plunger pump is characterized by further comprising a lubricating pump (13), a power gear shifting device and a transmission case (10) filled with oil, wherein an oil inlet of the variable plunger pump (12) is communicated with the transmission case (10) through a pipeline; an oil inlet of the lubricating pump (13) is communicated with a pipeline between the transmission case (10) and the variable plunger pump (12) through a pipeline, and an oil outlet of the lubricating pump is communicated with an oil inlet of the power gear shifting device through a pipeline.

3. The electro-hydraulic control system of claim 2, wherein: the oil cylinder control device is characterized in that an oil inlet of the oil cylinder control device is communicated with a pipeline between the power gear shifting device and the lubricating pump (13) through a pipeline.

4. The electro-hydraulic control system of claim 2 or 3, wherein: the hydraulic control system is characterized by further comprising an LS pressure controller (4) and an LS pressure control valve (6), wherein a control oil port of the LS pressure control valve (6) is communicated with a second oil outlet of the variable plunger pump (12) through a pipeline, and an oil inlet of the LS pressure control valve is communicated with a pipeline between the lubricating pump (13) and the power gear shifting device through a pipeline; the LS pressure control valve (6), the steering device and the multi-way valve device (16) are respectively in communication connection with the LS pressure controller (4).

5. The electro-hydraulic control system of claim 4, wherein: the power gear shifting device comprises at least one gear shifting mechanism, and an oil inlet of each gear shifting mechanism is communicated with an oil outlet of the lubricating pump (13) through a pipeline.

6. The electro-hydraulic control system of claim 5, wherein: the power gear shifting device further comprises a power gear shifting controller (19), each gear shifting mechanism comprises a gear shifting valve (17) and a wet clutch (18), an oil inlet of each gear shifting valve (17) is communicated with an oil outlet of the lubricating pump (13) through a pipeline, and a control oil port of each gear shifting valve is communicated with the corresponding wet clutch (18) through a pipeline; each gear shifting valve (17) is in communication connection with the power gear shifting controller (19).

7. The electro-hydraulic control system of claim 3, wherein: the oil cylinder control device comprises an AMT oil cylinder control valve group (28) and an energy accumulator (23), wherein an oil inlet of the AMT oil cylinder control valve group (28) is communicated with a pipeline between the lubricating pump (13) and the power gear shifting device through an energy accumulation pipeline; the accumulator (23) is communicated with the energy storage pipeline through a pipeline.

8. The electro-hydraulic control system of claim 7, wherein: the oil cylinder control device further comprises an oil cylinder controller (27), and the AMT oil cylinder control valve group (28) is in communication connection with the oil cylinder controller (27).

9. The electro-hydraulic control system of claim 8, wherein: the AMT oil cylinder control valve group (28) comprises at least one clutch control valve and at least one control clutch which corresponds to the clutch control valve one by one, the oil inlet of each clutch control valve is communicated with a pipeline between the lubricating pump (13) and the power gear shifting device through a pipeline, and the oil outlet of each clutch control valve is communicated with the corresponding control clutch through a pipeline; each clutch control valve is respectively in communication connection with the oil cylinder controller (27).

10. The electro-hydraulic control system of claim 8, wherein: the AMT oil cylinder control valve group (28) comprises at least one oil cylinder mechanism, wherein an oil inlet of each oil cylinder mechanism is communicated with a lubricating pump (13) and a pipeline between the power gear shifting devices through pipelines, and the oil inlets are in communication connection with the oil cylinder controller (27).

11. The electro-hydraulic control system of claim 4, wherein: a load sensing port on the steering device is communicated with the steering priority valve (3) through a pipeline, and a steering pressure sensor (2) is fixedly arranged on the pipeline between the load sensing port and the steering priority valve; a load sensing port on the multi-way valve device (16) is connected with a multi-way valve pressure sensor (1), and the steering pressure sensor (2) and the multi-way valve pressure sensor (1) are respectively in communication connection with the LS pressure controller (4).

12. The electro-hydraulic control system of claim 11, wherein: a variable pump outlet pressure sensor (5) is fixedly mounted on a pipeline between the variable plunger pump (12) and the steering priority valve (3), and the variable pump outlet pressure sensor (5) is in communication connection with the LS pressure controller (4).

13. The electro-hydraulic control system of claim 2 or 3, wherein: the oil inlet of the lubricating device is communicated with a pipeline between the lubricating pump (13) and the power gear shifting device through a lubricating pipeline; an oil outlet of the steering device is communicated with the lubricating pipeline through a pipeline.

14. The electro-hydraulic control system of claim 13, wherein: an overflow valve (34) is fixedly arranged on the lubricating pipeline.

15. The electro-hydraulic control system of claim 14, wherein: the oil inlet of the booster pump (8) is communicated with a pipeline between the transmission case (10) and the variable plunger pump (12) through a pipeline, the first oil outlet of the booster pump is communicated with the oil inlet of the variable plunger pump (12) through a pipeline, the second oil outlet of the booster pump is communicated with the oil inlet of the bypass control valve group (33) through a pipeline, the first oil outlet of the bypass control valve group (33) is communicated with the lubricating pipeline corresponding to the position between the overflow valve (34) and the lubricating device through a pipeline, and the second oil outlet of the bypass control valve group (33) is communicated with a pipeline between the booster pump (8) and the bypass control valve group (33) through a pipeline; an oil inlet of the lubricating pump (13) is communicated with a pipeline between the booster pump (8) and the transmission case (10) through a pipeline.

16. The electro-hydraulic control system of claim 15, wherein: an oil suction pressure switch (9) is fixedly installed at the communication position of the pipeline between the lubricating pump (13) and the booster pump (8) and the transmission case (10).

17. The electro-hydraulic control system of claim 13, wherein: the lubricating device comprises a lubricating control oil passage (21) and a cooler (22), wherein the inlet of the cooler (22) is communicated with the outlet of the lubricating pipeline, and the outlet of the cooler is communicated with the lubricating control oil passage (21) through a pipeline; an oil outlet of the steering device is communicated with a pipeline between the lubrication control oil passage (21) and the cooler (22) through a pipeline.

18. The electro-hydraulic control system of claim 17, wherein: the lubricating device further comprises a lubricating bypass valve group (20), wherein the inlet of the lubricating bypass valve group (20) is communicated with the position, close to the cooler (22), of the lubricating pipeline through a pipeline, and the outlet of the lubricating bypass valve group is communicated with the pipeline between the cooler (22) and the lubricating control oil channel (21) through a pipeline; and a pressure relief opening is also formed in the lubricating bypass valve group (20).

19. The electro-hydraulic control system of any of claims 1-3, wherein: still include relief valve (15), the oil inlet of relief valve (15) pass through the pipeline with turn to priority valve (3) with pipeline intercommunication between multiple unit valve device (16), multiple unit valve device (16) oil-out intercommunication returns oil pipe way, the oil-out of relief valve (15) pass through the pipeline with return oil pipe way intercommunication.

20. A tractor, its characterized in that: comprising an electro-hydraulic control system according to any of claims 1-19.