CN212509471U - Tractor power electro-hydraulic control system that shifts - Google Patents

Abstract

The utility model relates to a tractor technical field discloses a tractor power electro-hydraulic control system that shifts, include: the oil tank is used as a gearbox shell of the tractor and used for storing oil; the gear pump is connected with the oil tank and used for pumping oil; the electro-hydraulic control valve bank is connected with the gear pump, the electro-hydraulic control valve bank comprises a plurality of electromagnetic valves, oil inlet ends of the electromagnetic valves are connected with an oil liquid output end of the gear pump, and output ends of the electromagnetic valves are respectively connected with corresponding execution elements; the liquid inlet end of the emptying reversing valve is communicated with the oil liquid output end of the gear pump, and the liquid outlet end of the emptying reversing valve is connected with a plurality of oil ways. The tractor power shift electro-hydraulic control system can prevent air from remaining in a hydraulic system, save power consumption, reduce heating of the system and prolong the service life of a hydraulic element.

Description

Tractor power electro-hydraulic control system that shifts

Technical Field

The utility model relates to a tractor technical field especially relates to a tractor power electro-hydraulic control system that shifts.

Background

When the tractor is initially assembled or maintained, no hydraulic oil is in the hydraulic pipeline; when the hydraulic system is placed for a long time, oil at a high position in a pipeline of the hydraulic system flows to a low position due to the influence of self weight, so that air exists in the hydraulic pipeline. When air exists in oil, the air in the oil can influence the normal operation of the system after the hydraulic system operates, and the wet clutch is separated and combined to generate pause feeling.

Disclosure of Invention

In order to solve the technical problem, the utility model provides a tractor power electro-hydraulic control system that shifts can prevent that the air from remaining in hydraulic system to can save power consumption, reduce generating heat of system, extension hydraulic component life.

The utility model provides a technical scheme as follows:

a tractor power shift electro-hydraulic control system, comprising:

the oil tank is used as a gearbox shell of the tractor and used for storing oil;

the gear pump is connected with the oil tank and used for pumping oil;

the electro-hydraulic control valve bank is connected with the gear pump, the electro-hydraulic control valve bank comprises a plurality of electromagnetic valves, oil inlet ends of the electromagnetic valves are connected with an oil liquid output end of the gear pump, and output ends of the electromagnetic valves are respectively connected with corresponding execution elements;

the liquid inlet end of the emptying reversing valve is communicated with the oil liquid output end of the gear pump, and the liquid outlet end of the emptying reversing valve is connected with a plurality of oil ways.

In this technical scheme, when the tractor initial assembly, place for a long time or maintenance back, the fluid of eminence can be because of the influence flow direction low department of dead weight in the hydraulic system pipeline, and hydraulic circuit becomes to have the air like this. When air exists in the oil, the air in the oil can influence the normal operation of the system after the hydraulic system operates. Under the effect of evacuation switching-over valve, when the tractor starts, can arrange the air in the system to the greatest extent, guarantee when the system normally works, do not have the air in the hydraulic pressure oil circuit.

Further preferably, the method further comprises the following steps: a system pressure control valve;

the liquid inlet end of the system pressure control valve is communicated with the oil liquid output end of the gear pump, and the liquid outlet end of the system pressure control valve is connected to a plurality of oil ways.

Further preferably, the plurality of electromagnetic valves comprise a forward high-gear control valve, a forward Low-gear control valve and a reverse gear control valve, and the electro-hydraulic control valve group is provided with a P port, a Hi port, a Low port and an REV port; the port P is used as a liquid inlet of the electro-hydraulic control valve group, a liquid inlet end of the port P is connected with the gear pump, and a liquid outlet end of the port P is respectively connected with liquid inlet ends of the system pressure control valve, the forward high-gear control valve, the forward low-gear control valve, the backward reverse gear control valve and the emptying reversing valve;

the executing elements comprise a forward high-gear wet clutch, a forward low-gear wet clutch and a reverse gear wet clutch; the forward high-gear control valve is connected with the forward high-gear wet clutch through the Hi port, the forward Low-gear control valve is connected with the forward Low-gear wet clutch through the Low port, and the reverse gear control valve is connected with the reverse gear wet clutch through the REV port.

In the technical scheme, when the current high-gear wet clutch, the current low-gear wet clutch and the reverse gear wet clutch are not operated, all oil can overflow from a system pressure control valve in the electro-hydraulic control valve bank to a lubricating system or an oil return tank, so that power loss can be caused, the oil is converted into heat energy to cause the temperature rise of hydraulic oil, and the oil is deteriorated, so that the service life of elements is reduced. In order to reduce overflow loss, when the forward high-gear wet clutch, the forward low-gear wet clutch and the backward reverse wet clutch do not work, the emptying reversing valve is continuously electrified, so that oil is directly communicated to a lubricating system or an oil return tank through the emptying reversing valve, the gear pump runs in a no-load mode, namely, the oil output by the pump flows to the lubricating system or the oil return tank at zero pressure or low pressure, and therefore power consumption can be saved, heating of the system is reduced, and the service life is prolonged.

Further preferably, the oil passage includes a first oil return passage;

the first oil return oil path comprises a lubricating pressure control valve and a T port arranged on the electro-hydraulic control valve group, the liquid inlet end of the lubricating pressure control valve is connected with the system pressure control valve and the emptying reversing valve respectively, and the liquid outlet end of the lubricating pressure control valve is connected with the oil tank through the T port to form a circulation loop.

Further preferably, the oil passage further includes a second power train lubrication oil passage;

the second transmission system lubricating oil path comprises a Lub port arranged on the electro-hydraulic control valve group, the liquid inlet end of the Lub port is connected with the system pressure control valve and the emptying reversing valve respectively, the liquid outlet end of the Lub port is connected with a transmission system lubricating damping plug, the outlet end of the transmission system lubricating damping plug is connected with the oil tank, and the transmission system lubricating damping plug is used for performing forced lubrication on a tractor transmission system.

Further preferably, a wet clutch lubricating oil passage is provided in the second drive train lubricating oil passage, and a liquid outlet end of the wet clutch lubricating oil passage is connected to the forward high-gear wet clutch, the forward low-gear wet clutch, and the reverse wet clutch, respectively.

Further preferably, the method further comprises the following steps: a system accumulator;

and two ends of the system energy accumulator are respectively connected with the gear pump and the P port, and the system energy accumulator is used for playing a buffer role when the forward high-gear wet clutch, the forward low-gear wet clutch and the reverse gear wet clutch are separated and combined.

In the technical scheme, the system energy accumulator is an energy accumulator which is used for separating and combining a forward high-gear wet clutch, a forward low-gear wet clutch and a reverse gear wet clutch to play a buffering role. When the forward high-gear wet clutch, the forward low-gear wet clutch and the reverse wet clutch are combined and separated, the connected load can feed back impact to the tractor, and jerk and fluctuation caused to a hydraulic system can be caused. The system energy accumulator can absorb and release impact brought by the combination and separation of the forward high-gear wet clutch, the forward low-gear wet clutch and the reverse gear wet clutch, and has a buffer effect on a hydraulic system, so that the hitching is more stable. As an auxiliary power source, the pump power can be reduced, the efficiency is improved, the temperature rise is reduced, the energy is saved, and the energy loss of the system and the heat generation caused by the energy loss are reduced.

Further preferably, the method further comprises the following steps: a hydraulic radiator;

one end of the hydraulic radiator is connected with the gear pump, the other end of the hydraulic radiator is respectively connected with the port P and the system energy accumulator, and the hydraulic radiator is used for cooling oil.

In the technical scheme, the hydraulic radiator is a device for cooling oil in a hydraulic system, the oil is subjected to efficient heat exchange with cold air which forcibly flows in a heat exchanger, so that the oil temperature is reduced to the working temperature to ensure that the system can continuously and normally operate, and the work can be smoothly carried out.

Further preferably, the method further comprises the following steps: an oil absorption filter;

the one end of oil absorption filter with the oil tank is connected, the other end of oil absorption filter with the gear pump is connected, the oil absorption filter is used for filtering the fluid that gets into the gear pump.

In the technical scheme, the oil absorption filter is arranged at an oil suction port of the gear pump and used for protecting the gear pump and other hydraulic elements so as to avoid sucking polluted impurities, effectively control pollution of a hydraulic system and adjust the cleanliness of the hydraulic system.

Further preferably, the method further comprises the following steps: a pressure oil line oil filter;

one end of the pressure oil filter is connected with the hydraulic radiator, the other end of the pressure oil filter is respectively connected with the port P and the system energy accumulator, and the pressure oil filter is used for carrying out secondary filtration on oil.

In the technical scheme, the pressure oil line oil filter has the main functions of filtering oil, various impurities inevitably appear in a hydraulic system, and the cleanliness of the oil can be further improved through the pressure oil line oil filter.

Compared with the prior art, the utility model discloses a tractor power electro-hydraulic control system that shifts beneficial effect lies in:

in the utility model, when the tractor works, the tractor power gear-shifting electro-hydraulic control system can exhaust air in the system through the emptying reversing valve, so that no air exists in the hydraulic oil circuit when the system works normally; when the forward high-gear wet clutch, the forward low-gear wet clutch and the reverse gear wet clutch do not work, the emptying reversing valve is continuously electrified, so that oil is directly communicated to the lubricating system or the oil return tank through the emptying reversing valve, the gear pump runs in a no-load mode, namely, the oil output by the pump flows to the lubricating system or the oil return tank at zero pressure or low pressure, so that the power consumption can be saved, the heating of the system is reduced, and the service life is prolonged.

Drawings

The foregoing features, technical features, advantages and embodiments are further described in the following detailed description of the preferred embodiments, which is to be read in connection with the accompanying drawings.

FIG. 1 is a hydraulic schematic diagram of a power shift electro-hydraulic control system of a tractor according to the embodiment;

fig. 2 is a hydraulic schematic diagram of the electro-hydraulic control valve group of the embodiment.

The reference numbers illustrate:

1. the hydraulic transmission system comprises an oil tank, 2 parts of an oil suction filter, 3 parts of a gear pump, 4 parts of a hydraulic radiator, 5 parts of a pressure oil-way filter, 6 parts of a system accumulator, 7 parts of an electro-hydraulic control valve group, 8 parts of a forward high-gear wet clutch, 9 parts of a forward Low-gear wet clutch, 10 parts of a reverse-gear wet clutch, 11 parts of a transmission system lubrication damping plug, 12 parts of a system pressure control valve, 13 parts of a forward high-gear control valve, 14 parts of a forward Low-gear control valve, 15 parts of a reverse-gear control valve, 16 parts of an emptying reversing valve, 17 parts of a lubrication pressure control valve, 18 parts of a P port, 19 parts of a T port, 20 parts of a Lub port, 21 parts of a Hi port, 22 parts of a Low port.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

For the sake of simplicity, only the parts relevant to the present invention are schematically shown in the drawings, and they do not represent the actual structure as a product. In addition, in order to make the drawings concise and understandable, components having the same structure or function in some of the drawings are only schematically illustrated or only labeled. In this document, "one" means not only "only one" but also a case of "more than one".

It should be further understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

In the embodiments shown in the drawings, the directions (such as up, down, left, right, front, and rear) are used to explain the structure and movement of the various components of the present invention not absolutely, but relatively. These illustrations are appropriate when these components are in the positions shown in the figures. If the description of the positions of these components changes, the indication of these directions changes accordingly.

In addition, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not intended to indicate or imply relative importance. In the description of the present application, "a number" means at least one, such as one, two, etc., unless specifically limited otherwise. Furthermore, it is to be understood that the term "coupled" is to be interpreted broadly, unless explicitly stated or limited otherwise. For example, the connection can be fixed, detachable or integrated; can be mechanically or electrically connected; either directly or indirectly through intervening media, or through the communication between two elements.

In order to more clearly illustrate embodiments of the present invention or technical solutions in the prior art, specific embodiments of the present invention will be described below with reference to the accompanying drawings. It is obvious that the drawings in the following description are only examples of the invention, and that for a person skilled in the art, other drawings and embodiments can be obtained from these drawings without inventive effort.

As a specific embodiment, as shown in fig. 1 and fig. 2, the embodiment provides an electro-hydraulic control system for power shifting of a tractor, including: the device comprises an oil tank 1, a gear pump 3, an electro-hydraulic control valve group 7 and an emptying reversing valve 16. The oil tank 1 is used as a gearbox shell of the tractor for storing oil. The gear pump 3 is connected with the oil tank 1 and used for pumping oil. The electro-hydraulic control valve group 7 is connected with the gear pump 3, the electro-hydraulic control valve group 7 comprises a plurality of electromagnetic valves, oil inlet ends of the electromagnetic valves are connected with an oil output end of the gear pump 3, and output ends of the electromagnetic valves are respectively connected with corresponding execution elements. The liquid inlet end of the emptying reversing valve 16 is communicated with the oil liquid output end of the gear pump 3, and the liquid outlet end of the emptying reversing valve 16 is connected with a plurality of oil ways.

In the embodiment, the emptying reversing valve 16 is preferably arranged in the electro-hydraulic control valve group 7, so that the integration level is higher and the device is more compact. The liquid outlet end of the emptying reversing valve 16 is connected with one oil way or a plurality of parallel oil ways, when the tractor is initially assembled, placed for a long time or maintained, oil liquid at a high position in a hydraulic system pipeline flows to a low position due to the influence of dead weight, and thus air exists in the hydraulic pipeline. When air exists in the oil, the air in the oil can influence the normal operation of the system after the hydraulic system operates. Under the action of the emptying reversing valve 16, when the tractor is started, air in the system can be exhausted, and the condition that no air exists in a hydraulic oil circuit when the system works normally is ensured.

Further, tractor power shift electricity liquid control system still includes: the system pressure control valve 12 is characterized in that the liquid inlet end of the system pressure control valve 12 is respectively connected with a plurality of electromagnetic valves in parallel, the liquid outlet end of the system pressure control valve 12 is connected to a plurality of oil ways, the electromagnetic valves are preferably electromagnetic proportional valves, and the electric curve proportion control of the electromagnetic valves realizes that the wet clutch is combined and separated according to curves to achieve different running states. The electromagnetic valves comprise a forward high-gear control valve 13, a forward Low-gear control valve 14 and a reverse gear control valve 15, and the electro-hydraulic control valve group 7 is provided with a P port 18, a Hi port 21, a Low port 22 and an REV port 23. The P port 18 is used as a liquid inlet of the electro-hydraulic control valve group 7, the liquid inlet end of the P port 18 is connected with the gear pump 3, and the liquid outlet end of the P port 18 is respectively connected with the system pressure control valve 12, the forward high-gear control valve 13, the forward low-gear control valve 14, the backward reverse gear control valve 15 and the emptying reversing valve 16. The liquid inlet end of the system pressure control valve 12 is arranged between the liquid outlet end of the P port 18 and the forward high gear control valve 13, the forward low gear control valve 14 and the backward reverse gear control valve 15; the liquid inlet end of the emptying reversing valve 16 is respectively connected with the forward high gear control valve 13, the forward low gear control valve 14 and the backward reverse gear control valve 15; the liquid outlet end of the emptying reversing valve 16 and the liquid outlet end of the system pressure control valve 12 are connected with a plurality of parallel oil paths. The forward high range control valve 13 is connected to the forward high range wet clutch 8 through a Hi port 21, the forward Low range control valve 14 is connected to the forward Low range wet clutch 9 through a Low port 22, and the reverse control valve 15 is connected to the reverse wet clutch 10 through a REV port 23.

In this embodiment, the evacuation switching valve 16 is a two-position two-way electromagnetic switch valve, and is normally closed in the oil passage. When the tractor works, the emptying reversing valve 16 is electrified due to a starting instruction, the electromagnetic coil is attracted, the oil duct of the emptying reversing valve 16 is switched to be in a connected state, and at the moment, oil can circulate in the system pipeline in a hollow load mode to exhaust air completely. When the air is exhausted, the solenoid of the exhaust directional valve 16 is de-energized, and the oil passage is switched to a closed state, which is the normal operating state of the hydraulic system. When the forward high-gear control valve 13, the forward low-gear control valve 14 and the reverse-gear control valve 15 are all in the closed state, in order to reduce overflow loss, the emptying reversing valve 22 is continuously powered, so that oil is directly communicated to a lubricating system or an oil return tank through the emptying reversing valve 22, the gear pump 3 is in no-load operation, namely, all the oil output by the pump flows to the lubricating system or the oil return tank at zero pressure or low pressure, so that the power consumption can be saved, the heat generation of the system is reduced, and the service life is prolonged.

In another embodiment, as shown in fig. 1 and fig. 2, on the basis of the above embodiment, the oil path includes a first oil return path; the first oil return oil circuit comprises a lubricating pressure control valve 17 and a T port 19 arranged on the electro-hydraulic control valve group 7, the liquid inlet end of the lubricating pressure control valve 17 is respectively connected with the system pressure control valve 12 and the emptying reversing valve 16, and the liquid outlet end of the lubricating pressure control valve 17 is connected with the oil tank 1 through the T port 19 to form a circulation loop.

Further, the oil path further comprises a second transmission system lubricating oil path; the second transmission system lubricating oil path comprises a Lub port 20 arranged on the electro-hydraulic control valve group 7, the liquid inlet end of the Lub port 20 is connected with the system pressure control valve 12 and the emptying reversing valve 16 respectively, the liquid outlet end of the Lub port 20 is connected with a transmission system lubricating damping plug 11, the outlet end of the transmission system lubricating damping plug 11 is connected with the oil tank 1, and the transmission system lubricating damping plug 11 is used for performing forced lubrication on the tractor transmission system.

Furthermore, a wet clutch lubricating oil passage is arranged on the second transmission system lubricating oil passage, and the liquid outlet end of the wet clutch lubricating oil passage is respectively communicated with the forward high-gear wet clutch 8, the forward low-gear wet clutch 9 and the reverse wet clutch 10.

Preferably, the liquid inlet end of the wet clutch lubricating oil path is connected between the Lub port 20 and the transmission system lubricating damping plug 11, and the liquid outlet end is respectively communicated to the forward high-gear wet clutch 8, the forward low-gear wet clutch 9 and the reverse gear wet clutch 10 to provide lubrication for each wet clutch.

In another embodiment, as shown in fig. 1 and fig. 2, on the basis of the above embodiments, the tractor power shift electro-hydraulic control system further includes: a system accumulator 6. Two ends of the system energy accumulator 6 are respectively connected with the gear pump 3 and the P port 18, and the system energy accumulator 6 is used for ensuring the stability of the separation and combination of the forward high-gear wet clutch 8, the forward low-gear wet clutch 9 and the reverse gear wet clutch 10. The system energy accumulator 6 is an energy accumulator which has a buffer function by separating and combining a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10. When the forward high wet clutch 8, the forward low wet clutch 9, and the reverse wet clutch 10 are engaged and disengaged, the connected load feeds back an impact to the tractor, and a jerk fluctuation is caused to the hydraulic system. The system energy accumulator 6 can absorb and release impact caused by the combination and separation of the forward high-gear wet clutch 8, the forward low-gear wet clutch 9 and the reverse gear wet clutch 10, and has a buffering effect on a hydraulic system, so that the hitching is more stable. As an auxiliary power source, the pump power can be reduced, the efficiency is improved, the temperature rise is reduced, the energy is saved, and the energy loss of the system and the heat generation caused by the energy loss are reduced.

Further, as shown in fig. 1 and fig. 2, the tractor power shift electro-hydraulic control system further includes: a hydraulic radiator 4, an oil suction filter 2 and a pressure oil filter 5. One end of the hydraulic radiator 4 is connected with the gear pump 3, the other end of the hydraulic radiator 4 is respectively connected with the P port 18 and the system energy accumulator 6, and the hydraulic radiator 4 is used for cooling oil. The hydraulic radiator 4 is a device for cooling oil in a hydraulic system, and the oil is subjected to efficient heat exchange with cold air which forcibly flows in a heat exchanger, so that the oil temperature is reduced to the working temperature to ensure that the system can continuously and normally operate, and the work can be smoothly carried out. The one end and the oil tank 1 of oil absorption filter 2 are connected, and the other end and the gear pump 3 of oil absorption filter 2 are connected, and oil absorption filter 2 is used for filtering the fluid that gets into gear pump 3. The oil absorption filter 2 is arranged at an oil absorption port of the gear pump 3 and used for protecting the gear pump 3 and other hydraulic elements so as to avoid absorbing pollution impurities, effectively control the pollution of a hydraulic system and adjust the cleanliness of the hydraulic system. One end of the pressure oil filter 5 is connected with the hydraulic radiator 4, the other end of the pressure oil filter 5 is respectively connected with the P port 18 and the system accumulator 6, and the pressure oil filter 5 is used for carrying out secondary filtration on oil. The pressure oil-way oil filter 5 mainly functions to filter oil, various impurities inevitably appear in a hydraulic system, and the cleanliness of the oil can be further improved through the pressure oil-way oil filter 5.

Under the normal working condition of the tractor, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are electrically triggered, and the right oil circuit of the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 is connected, so that the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10 are respectively combined, and corresponding mechanisms are driven to enable the forward high gear, the forward low gear and the reverse gear to work. The forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are de-energized, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are positioned at the left position, the oil path is closed, the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10 are respectively separated, the corresponding mechanisms stop operating, and the forward high gear, the forward low gear and the reverse gear stop operating. The drain switch valve 16 will be energized to allow oil to pass directly through the drain switch valve 16 to the lubrication system or to the return tank. The forward high wet clutch 8, the forward low wet clutch 9, and the reverse wet clutch 10 cannot be engaged at the same time.

In this embodiment, the specific oil path route of the tractor power shift electro-hydraulic control system is as follows:

emptying an oil path:

as shown in fig. 1 and 2, each element is in an initial state, when the tractor is started, the evacuation switching valve 16 is energized according to a start command, the solenoid is closed, and the oil passage is switched to a connected state. Oil enters from a P port 18 of an electro-hydraulic control valve group 7 through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4, a pressure oil-way oil filter 5, and is preferentially shunted through an evacuation reversing valve 16 in the right direction, and no matter whether a forward high-gear control valve 13, a forward low-gear control valve 14 and a reverse-gear control valve 15 are in a connected state or not, one path of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively lubricated for a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse-gear wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop. At the moment, oil liquid can be circulated in the system pipeline in a hollow mode, air is exhausted, and the air cannot enter each wet clutch. After the air is exhausted, if the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are all in the closed state, the emptying reversing valve 16 is continuously powered on, and all the oil flows to a lubricating system or an oil return tank, so that the purpose of reducing power consumption is achieved. When the air is exhausted, if one of the forward high range control valve 13, the forward low range control valve 14 and the reverse range control valve 15 is in the on state, the emptying reversing valve 16 will lose power.

(II) wet clutch working oil path route: as shown in fig. 1 and 2, each element is in an initial state after evacuation is started.

1. Working oil path route of forward high-gear wet clutch 8:

when the electric liquid control valve is not electrified, oil enters from a P port 18 of the electro-hydraulic control valve group 7 through an oil tank 1, an oil suction oil filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil way oil filter 5, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are in a closed state, the evacuation reversing valve 16 is continuously electrified after evacuation, the oil is shunted at the right position through the evacuation reversing valve 16, and one path of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively lubricated for the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward high-gear control valve 13 is powered on, the electromagnetic coil of the forward high-gear control valve 13 is attracted to be positioned at the right position, the oil path is communicated, and the emptying reversing valve 16 is powered off at the same time. Oil enters through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5 through a P port 18 of an electro-hydraulic control valve group 7, passes through the right position of a forward high-gear control valve 13, and fills the forward high-gear wet clutch 8. And meanwhile, the system energy accumulator 6 is filled with liquid, and system fluctuation is buffered. Because the forward high-gear control valve 13 is switched on, oil flows into the forward high-gear wet clutch 8 to be combined according to a current curve, and due to load change, the system pressure control valve 12 can fluctuate momentarily to influence system pressure and stably combine the wet clutch to cause impact, and at the moment, the system energy accumulator 6 can absorb system impact to stabilize the system pressure, so that the forward high-gear wet clutch 8 can be stably combined. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward high-gear control valve 13 is powered off, the electromagnetic coil of the forward high-gear control valve 13 is released to be in the left position, an oil way is closed, oil passes through the oil tank 1, the oil suction oil filter 2, the gear pump 3, the hydraulic radiator 4 and the pressure oil way oil filter 5, at the moment, the forward high-gear control valve 13, the forward low-gear control valve 14 and the reverse gear control valve 15 are in a closed state, the emptying reversing valve 16 is powered on again, the oil is shunted through the right position of the emptying reversing valve 16, and one way of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively used for lubricating the forward high-gear wet clutch 8, the forward low-gear wet clutch 9 and; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop. The oil in the forward high-gear wet clutch 8 is bypassed to each lubricating system by the system pressure control valve 12 through the left position of the forward high-gear control valve 13, and finally returns to the oil tank 1.

2. Working oil path route of forward low-gear wet clutch 9:

when the electric liquid control valve is not electrified, oil enters from a P port 18 of the electro-hydraulic control valve group 7 through an oil tank 1, an oil suction oil filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil way oil filter 5, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are in a closed state, the evacuation reversing valve 16 is continuously electrified after evacuation, the oil is shunted at the right position through the evacuation reversing valve 16, and one path of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively lubricated for the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward low gear control valve 14 is powered on, the electromagnetic coil of the forward low gear control valve 14 is attracted to be positioned at the right position, the oil path is connected, and the emptying reversing valve 16 is powered off at the same time. Oil enters through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5 through a P port 18 of an electro-hydraulic control valve group 7 and fills the forward low-gear wet clutch 9 through the right position of a forward low-gear control valve 14. And meanwhile, the system energy accumulator 6 is filled with liquid, and system fluctuation is buffered. Because the forward low-gear control valve 14 is switched on, oil flows into the forward low-gear wet clutch 9 to be combined according to a current curve, and due to load change, the system pressure control valve 12 can fluctuate momentarily to influence system pressure and stably combine the wet clutch to cause impact, and at the moment, the system energy accumulator 6 can absorb system impact to stabilize the system pressure, so that the forward low-gear wet clutch 9 can be stably combined. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward low-gear control valve 14 is powered off, the electromagnetic coil of the forward low-gear control valve 14 is released to be in the left position, an oil way is closed, oil passes through the oil tank 1, the oil suction oil filter 2, the gear pump 3, the hydraulic radiator 4 and the pressure oil way oil filter 5, at the moment, the forward high-gear control valve 13, the forward low-gear control valve 14 and the reverse gear control valve 15 are in a closed state, the emptying reversing valve 16 is powered on again, the oil is shunted through the right position of the emptying reversing valve 16, one way of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively used for lubricating the forward high-gear wet clutch 8, the forward low-gear wet clutch 9 and the; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop. The oil in the forward low wet clutch 9 is bypassed to each lubrication system by the system pressure control valve 12 through the left position of the forward low control valve 14, and finally returns to the oil tank 1.

3. Working oil path route of the reverse wet clutch 10:

when the electric liquid control valve is not electrified, oil enters from a P port 18 of the electro-hydraulic control valve group 7 through an oil tank 1, an oil suction oil filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil way oil filter 5, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are in a closed state, the evacuation reversing valve 16 is continuously electrified after evacuation, the oil is shunted at the right position through the evacuation reversing valve 16, and one path of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively lubricated for the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the reverse gear control valve 15 is powered on, the electromagnetic coil of the reverse gear control valve 15 is attracted and positioned at the right position, the oil path is connected, and the emptying reversing valve 16 is simultaneously powered off. Oil enters through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5 through a P port 18 of an electro-hydraulic control valve group 7, passes through a reverse gear control valve 15 at the right position, and fills the reverse gear clutch 10. And meanwhile, the system energy accumulator 6 is filled with liquid, and system fluctuation is buffered. Because the reverse gear control valve 15 is switched on, oil flows into the reverse gear wet clutch 10 to be combined according to a current curve, and due to load change, the system pressure control valve 12 can fluctuate momentarily to influence system pressure and stably combine the wet clutch to cause impact, and at the moment, the system energy accumulator 6 can absorb system impact to stabilize the system pressure, so that the reverse gear wet clutch 10 can be stably combined. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the reverse gear control valve 15 is powered off, the electromagnetic coil of the reverse gear control valve 15 is released to be in the left position, the oil way is closed, oil passes through the oil tank 1, the oil suction filter 2, the gear pump 3, the hydraulic radiator 4 and the pressure oil way filter 5, at the moment, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are in a closed state, the emptying reversing valve 16 is powered on again, the oil is shunted through the right position of the emptying reversing valve 16, and one way of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 to respectively lubricate the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop. The oil in the reverse wet clutch 10 is bypassed to each lubrication system by the system pressure control valve 12 through the left position of the reverse control valve 15, and finally returns to the oil tank 1.

(III) switching working oil path lines among the wet clutches: as shown in fig. 1 and 2, each element is in an initial state after evacuation is started.

1. The working oil path route is switched between the forward high-gear wet clutch 8 and the forward low-gear wet clutch 9:

when the electric liquid control valve is not electrified, oil enters from a P port 18 of the electro-hydraulic control valve group 7 through an oil tank 1, an oil suction oil filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil way oil filter 5, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are in a closed state, the evacuation reversing valve 16 is continuously electrified after evacuation, the oil is shunted at the right position through the evacuation reversing valve 16, and one path of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively lubricated for the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward high-gear control valve 13 is powered on, the electromagnetic coil of the forward high-gear control valve 13 is attracted to be positioned at the right position, the oil path is communicated, and the emptying reversing valve 16 is powered off at the same time. Oil enters through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5 through a P port 18 of an electro-hydraulic control valve group 7, passes through the right position of a forward high-gear control valve 13, and fills the forward high-gear wet clutch 8. And meanwhile, the system energy accumulator 6 is filled with liquid, and system fluctuation is buffered. Because the forward high-gear control valve 13 is switched on, oil flows into the forward high-gear wet clutch 8 to be combined according to a current curve, and due to load change, the system pressure control valve 12 can fluctuate momentarily to influence system pressure and stably combine the wet clutch to cause impact, and at the moment, the system energy accumulator 6 can absorb system impact to stabilize the system pressure, so that the forward high-gear wet clutch 8 can be stably combined. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward high gear and the forward low gear are switched, when the forward high gear is shifted to the forward low gear, namely the forward high gear control valve 13 is powered off and the forward low gear control valve 14 is powered on, the electromagnetic coil of the forward high gear control valve 13 is released to be in the left position, and the oil way is closed. The solenoid of the forward low gear control valve 14 is combined at the right position, and the oil circuit is connected. When in switching, the respective power-off and power-on of the proportional valve are carried out simultaneously according to a current curve. The forward high wet clutch 8 and the forward low wet clutch 9 are also simultaneously disengaged and engaged. The oil passes through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5, passes through a system pressure control valve 12, and controls the system pressure. At this time, the forward high-gear control valve 13 is in the left position, the oil path is closed, the forward low-gear control valve 14 is in the right position, the oil path is connected, the reverse gear control valve 15 is in the left position, the oil path is closed, and the oil in the forward high-gear wet clutch 8 bypasses the system pressure control valve 12 to be distributed to each lubricating system through the left position of the forward high-gear control valve 13 and finally returns to the oil tank 1.

When the forward high-gear wet clutch 8 is separated, oil enters through a P port of the electro-hydraulic control valve group 7 and passes through the right position of the forward low-gear control valve 14 to charge the forward low-gear wet clutch 9. Because the oil liquid flows into the forward low-gear wet clutch 9, the forward low-gear wet clutch 9 is combined according to a current curve, the system pressure control valve 12 can fluctuate briefly due to load change, the system pressure is influenced, impact can be caused by stable combination of the wet clutch, the system energy accumulator 6 can absorb system impact at the moment, the system pressure is stable, and the forward low-gear wet clutch 9 can be combined stably. The forward high wet clutch 8 is disengaged and engaged simultaneously with the forward low wet clutch 9, and switching between the forward high and the forward low is realized. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

2. The working oil path route is switched between the forward high-gear wet clutch 8 and the reverse gear wet clutch 10:

when the electric liquid control valve is not electrified, oil enters from a P port 18 of the electro-hydraulic control valve group 7 through an oil tank 1, an oil suction oil filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil way oil filter 5, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are in a closed state, the evacuation reversing valve 16 is continuously electrified after evacuation, the oil is shunted at the right position through the evacuation reversing valve 16, and one path of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively lubricated for the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward high-gear control valve 13 is powered on, the electromagnetic coil of the forward high-gear control valve 13 is attracted to be positioned at the right position, the oil path is communicated, and the emptying reversing valve 16 is powered off at the same time. Oil enters through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5 through a P port 18 of an electro-hydraulic control valve group 7, passes through the right position of a forward high-gear control valve 13, and fills the forward high-gear wet clutch 8. And meanwhile, the system energy accumulator 6 is filled with liquid, and system fluctuation is buffered. Because the forward high-gear control valve 13 is switched on, oil flows into the forward high-gear wet clutch 8 to be combined according to a current curve, and due to load change, the system pressure control valve 12 can fluctuate momentarily to influence system pressure and stably combine the wet clutch to cause impact, and at the moment, the system energy accumulator 6 can absorb system impact to stabilize the system pressure, so that the forward high-gear wet clutch 8 can be stably combined. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward high gear and the reverse gear are switched, when the forward high gear is shifted to the reverse gear, namely the forward high gear control valve 13 is powered off, and the reverse gear control valve 15 is powered on, the electromagnetic coil of the forward high gear control valve 13 is released to be in the left position, and the oil way is closed. The reverse gear control valve 15 is connected with the electromagnetic coil at the right position, and the oil path is communicated. When in switching, the respective power-off and power-on of the proportional valve are carried out simultaneously according to a current curve. The forward high wet clutch 8 and the reverse wet clutch 10 are also simultaneously disengaged and engaged. The oil passes through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5, passes through a system pressure control valve 12, and controls the system pressure. At this time, the forward high-gear control valve 13 is in the left position, the oil path is closed, the reverse control valve 15 is in the right position, the oil path is connected, the forward low-gear control valve 14 is in the left position, the oil path is closed, and the oil in the forward high-gear wet clutch 8 bypasses the system pressure control valve 12 to be distributed to each lubricating system through the left position of the forward high-gear control valve 13 and finally returns to the oil tank 1.

When the forward high-gear wet clutch 8 is separated, oil enters through a P port of the electro-hydraulic control valve group 7 and passes through the right position of the reverse gear control valve 15 to charge the reverse gear wet clutch 10. Because the oil fluid flow retreats and reverses the wet clutch 10 of the gear, so that the oil fluid flow retreats and reverses the gear and the wet clutch 10 of the gear is combined according to a current curve, and due to load change, transient fluctuation can occur in a system pressure control valve 12, so that system pressure is influenced, impact can be caused to the stable combination of the wet clutch, at the moment, the system energy accumulator 6 can absorb system impact, the system pressure is stable, and the retreating and reversing wet. The forward high wet clutch 8 is disengaged and the reverse wet clutch 10 is engaged at the same time, and switching between the forward high and reverse gears is realized. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

3. The working oil path route is switched between the forward low-gear wet clutch 9 and the reverse gear wet clutch 10:

when the electric liquid control valve is not electrified, oil enters from a P port 18 of the electro-hydraulic control valve group 7 through an oil tank 1, an oil suction oil filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil way oil filter 5, the forward high gear control valve 13, the forward low gear control valve 14 and the reverse gear control valve 15 are in a closed state, the evacuation reversing valve 16 is continuously electrified after evacuation, the oil is shunted at the right position through the evacuation reversing valve 16, and one path of the oil comes out from a Lub port 20 of the electro-hydraulic control valve group 7 and is respectively lubricated for the forward high gear wet clutch 8, the forward low gear wet clutch 9 and the reverse gear wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward low gear control valve 14 is powered on, the electromagnetic coil of the forward low gear control valve 14 is attracted to be positioned at the right position, the oil path is connected, and the emptying reversing valve 16 is powered off at the same time. Oil enters through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5 through a P port 18 of an electro-hydraulic control valve group 7 and fills the forward low-gear wet clutch 9 through the right position of a forward low-gear control valve 14. And meanwhile, the system energy accumulator 6 is filled with liquid, and system fluctuation is buffered. Because the forward low-gear control valve 14 is switched on, oil flows into the forward low-gear wet clutch 9 to be combined according to a current curve, and due to load change, the system pressure control valve 12 can fluctuate momentarily to influence system pressure and stably combine the wet clutch to cause impact, and at the moment, the system energy accumulator 6 can absorb system impact to stabilize the system pressure, so that the forward low-gear wet clutch 9 can be stably combined. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

When the forward low gear and the reverse gear are switched, when the forward low gear is shifted to the reverse gear, namely the forward low gear control valve 14 is powered off, and the reverse gear control valve 15 is powered on, the electromagnetic coil of the forward low gear control valve 14 is released to be in the left position, and the oil way is closed. The reverse gear control valve 15 is connected with the electromagnetic coil at the right position, and the oil path is communicated. When in switching, the respective power-off and power-on of the proportional valve are carried out simultaneously according to a current curve. The forward low wet clutch 9 and the reverse wet clutch 10 are also simultaneously disengaged and engaged. The oil passes through an oil tank 1, an oil suction filter 2, a gear pump 3, a hydraulic radiator 4 and a pressure oil line filter 5, passes through a system pressure control valve 12, and controls the system pressure. At this time, the forward low gear control valve 14 is in the left position, the oil path is closed, the reverse gear control valve 15 is in the right position, the oil path is connected, the forward high gear control valve 15 is in the left position, the oil path is closed, and the oil in the forward low gear wet clutch 9 bypasses the system pressure control valve 12 to be distributed to each lubricating system through the left position of the forward low gear control valve 14, and finally returns to the oil tank 1.

When the forward low-gear wet clutch 9 is separated, oil enters through a P port of the electro-hydraulic control valve group 7 and passes through the right position of the reverse gear control valve 15 to charge the reverse gear wet clutch 10. Because the oil fluid flow retreats and reverses the wet clutch 10 of the gear, so that the oil fluid flow retreats and reverses the gear and the wet clutch 10 of the gear is combined according to a current curve, and due to load change, transient fluctuation can occur in a system pressure control valve 12, so that system pressure is influenced, impact can be caused to the stable combination of the wet clutch, at the moment, the system energy accumulator 6 can absorb system impact, the system pressure is stable, and the retreating and reversing wet. The forward low wet clutch 9 is disengaged and engaged with the reverse wet clutch 10, and the forward low and reverse gears are switched. Meanwhile, the flow is divided by a system pressure control valve 12, and one path of the flow is discharged from a Lub port 20 of the electro-hydraulic control valve group 7 and respectively lubricates a forward high-gear wet clutch 8, a forward low-gear wet clutch 9 and a reverse wet clutch 10; and the lubricating oil enters the oil tank 1 after lubricating the transmission system from the transmission system lubricating damping plug 11 to form a circulating loop. The other path controls the lubricating pressure through a lubricating pressure control valve 17 and directly enters the oil tank 1 to form a circulation loop.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or recited in detail in a certain embodiment.

It should be noted that the above embodiments can be freely combined as necessary. The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (10)

1. The utility model provides a tractor power electrohydraulic control system that shifts which characterized in that includes:

the oil tank is used as a gearbox shell of the tractor and used for storing oil;

the gear pump is connected with the oil tank and used for pumping oil;

the electro-hydraulic control valve bank is connected with the gear pump, the electro-hydraulic control valve bank comprises a plurality of electromagnetic valves, oil inlet ends of the electromagnetic valves are connected with an oil liquid output end of the gear pump, and output ends of the electromagnetic valves are respectively connected with corresponding execution elements;

the liquid inlet end of the emptying reversing valve is communicated with the oil liquid output end of the gear pump, and the liquid outlet end of the emptying reversing valve is connected with a plurality of oil ways.

2. The tractor power shift electro-hydraulic control system of claim 1, further comprising: a system pressure control valve;

the liquid inlet end of the system pressure control valve is communicated with the oil liquid output end of the gear pump, and the liquid outlet end of the system pressure control valve is connected to a plurality of oil ways.

3. The tractor power shift electro-hydraulic control system of claim 2, characterized in that:

the electromagnetic valves comprise a forward high-gear control valve, a forward Low-gear control valve and a backward reverse gear control valve, and the electro-hydraulic control valve group is provided with a P port, a Hi port, a Low port and an REV port; the port P is used as a liquid inlet of the electro-hydraulic control valve group, a liquid inlet end of the port P is connected with the gear pump, and a liquid outlet end of the port P is respectively connected with liquid inlet ends of the system pressure control valve, the forward high-gear control valve, the forward low-gear control valve, the backward reverse gear control valve and the emptying reversing valve;

the executing elements comprise a forward high-gear wet clutch, a forward low-gear wet clutch and a reverse gear wet clutch; the forward high-gear control valve is connected with the forward high-gear wet clutch through the Hi port, the forward Low-gear control valve is connected with the forward Low-gear wet clutch through the Low port, and the reverse gear control valve is connected with the reverse gear wet clutch through the REV port.

4. The tractor power shift electro-hydraulic control system of claim 3, characterized in that:

the oil path comprises a first oil return path;

the first oil return oil path comprises a lubricating pressure control valve and a T port arranged on the electro-hydraulic control valve group, the liquid inlet end of the lubricating pressure control valve is connected with the system pressure control valve and the emptying reversing valve respectively, and the liquid outlet end of the lubricating pressure control valve is connected with the oil tank through the T port to form a circulation loop.

5. The tractor power shift electro-hydraulic control system of claim 4, characterized in that:

the oil circuit further comprises a second transmission system lubricating oil circuit;

the second transmission system lubricating oil path comprises a Lub port arranged on the electro-hydraulic control valve group, the liquid inlet end of the Lub port is connected with the system pressure control valve and the emptying reversing valve respectively, the liquid outlet end of the Lub port is connected with a transmission system lubricating damping plug, the outlet end of the transmission system lubricating damping plug is connected with the oil tank, and the transmission system lubricating damping plug is used for performing forced lubrication on a tractor transmission system.

6. The tractor power shift electro-hydraulic control system of claim 5, characterized in that:

and a wet clutch lubricating oil path is arranged on the second transmission system lubricating oil path, and the liquid outlet end of the wet clutch lubricating oil path is respectively communicated to the forward high-gear wet clutch, the forward low-gear wet clutch and the reverse wet clutch.

7. The tractor power shift electro-hydraulic control system of claim 3, further comprising: a system accumulator;

and two ends of the system energy accumulator are respectively connected with the gear pump and the P port, and the system energy accumulator is used for playing a buffer role when the forward high-gear wet clutch, the forward low-gear wet clutch and the reverse gear wet clutch are separated and combined.

8. The tractor power shift electro-hydraulic control system of claim 7, further comprising: a hydraulic radiator;

one end of the hydraulic radiator is connected with the gear pump, the other end of the hydraulic radiator is respectively connected with the port P and the system energy accumulator, and the hydraulic radiator is used for cooling oil.

9. The tractor power shift electro-hydraulic control system of claim 8, further comprising: an oil absorption filter;

the one end of oil absorption filter with the oil tank is connected, the other end of oil absorption filter with the gear pump is connected, the oil absorption filter is used for filtering the fluid that gets into the gear pump.

10. The tractor power shift electro-hydraulic control system of claim 9, further comprising: a pressure oil line oil filter;

one end of the pressure oil filter is connected with the hydraulic radiator, the other end of the pressure oil filter is respectively connected with the port P and the system energy accumulator, and the pressure oil filter is used for carrying out secondary filtration on oil.

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