Electric control two-gear high-speed box and hydraulic system thereof

Abstract

The utility model discloses an electric control two-gear high-speed box, which relates to the technical field of engineering machinery and comprises a box body, a coarse filter element, a variable speed pump, a fine filter element, a pressure regulating valve, an oil cooler, a gear shifting control valve, a gearbox, a clutch and an oil level gauge. The clutch oil pressure is adjusted to be within the working pressure range through the pressure adjusting valve, pressure fluctuation is small, the pressure adjusting response speed is high, the pressure adjusting valve is compact in structure, whole machine layout is facilitated, the speed change valve is of an embedded electric proportional valve structure, a clutch pressure buildup curve is controlled through PWM current output of an electric control program, and the clutch pressure buildup curve is controlled. The stable combination of a clutch in the gear shifting process is achieved, the gear shifting quality is improved, an electric control program can comprehensively consider the deviation of factors such as temperature and oil viscosity, a pressurization curve is corrected, in a variable speed hydraulic system, an outer seal on a piston is of an L-shaped structure, the sealing lip structure is optimally designed, the pressure maintaining performance is good, and the abrasion resistance is good; the device is suitable for severe working conditions such as high load, high temperature and continuous operation of loaders.

Description

Technical Field

[0001] The utility model relates to the technical field of engineering machinery, in particular to an electronically controlled two-speed high-speed box and a hydraulic system thereof. Background Art

[0002] Wheel loaders can be divided into fuel loaders and electric loaders according to their power sources. With the continuous advancement of the country's "dual carbon" strategy, electric loaders have gradually become a popular choice in the market. The market sales of electric loaders have increased rapidly. In 2023, the total sales of electric loaders were 3,595 units, accounting for 6.36% of the total sales of loaders, an increase of more than 300% year-on-year compared with 2022.

[0003] At present, most of the electronically controlled gearboxes used in electric loaders on the market are modified or technically upgraded from oil-mounted ones, and have the disadvantages of large size, multiple gears, and complex structure. Due to the large number of gears, the gear shifting operation is frequent and the operation is difficult, making it difficult to give full play to the advantages of the motor's high speed and wide high-efficiency speed range. At the same time, due to the upgrade of the gearbox on the traditional oil-mounted one, most of the key components inside the box, such as sealing rings, are borrowed, which makes it difficult to meet the use requirements under high speed. In terms of hydraulic systems, the speed-changing and torque-changing hydraulic system of the traditional oil-mounted one is matched with the torque converter, the speed-changing pressure system of the gearbox, and the torque-changing hydraulic system. Since the electric loader has cancelled the original torque converter, the original hydraulic system can hardly meet the needs of the electric loader.

[0004] Therefore, there is an urgent need for an electronically controlled second-speed high-speed box and a hydraulic system thereof to solve the above-mentioned technical problems. Utility Model Content

[0005] The purpose of the utility model is to provide an electronically controlled two-speed high-speed box to solve the problems raised by the above-mentioned background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an electronically controlled two-speed high-speed gearbox, comprising a gearbox, a coarse filter element, a speed pump, a fine filter element, a pressure regulating valve, an oil cooler, a shift control valve, a gearbox, a clutch and an oil level gauge, wherein the pressure regulating valve and the shift control valve are integrally mounted on the gearbox, the coarse filter element is mounted on the bottom of the gearbox, the speed pump is connected to the oil outlet of the coarse filter element via an oil suction port arranged at the oil inlet, and the outlet of the speed pump is connected to the fine filter element, the clutch comprises a first-gear clutch and a second-gear clutch, the clutch adopts a wear-resistant composite material, the sealing ring on the clutch piston adopts an L-shaped structure, and the sealing lip on the clutch adopts an arc structure, the two ends of the pressure regulating valve are respectively provided with a valve inlet, a pressure oil outlet and an overflow oil outlet, the valve The inlet is fixedly connected to the outlet of the fine filter element through a pipeline, the pressure oil outlet is fixedly connected to the shift control valve through a pipeline, the overflow oil outlet is connected to the oil inlet of the oil cooler through a pipeline, the oil inlet of the shift control valve is connected to the pressure regulating valve, and the oil outlet of the shift control valve is respectively connected to the first-gear clutch and the second-gear clutch through a hose, a first-gear electric proportional valve and a second-gear electric proportional valve are installed on the valve body of the shift control valve, the connectors of the first-gear electric proportional valve and the second-gear electric proportional valve are connected to the controller through a wiring harness, and the pressure of the first-gear clutch and the second-gear clutch is controlled by a PWM current signal, and a speed sensor is installed on one side of the box body, the speed sensor and the clutch are arranged one by one, and the speed sensor is used to detect the input speed and output speed of the corresponding clutch.

[0007] Preferably, one end of the box body is fixedly connected to an output end face gear flange, and the other end of the box body is fixedly connected to an input end face gear flange, and the input end face gear flange and the output end face gear flange both adopt the structural form of end face gears, the input end face gear flange is connected to the motor, and the output end face gear flange is connected to the output transmission shaft.

[0008] Preferably, a main pressure measuring point is provided on the pressure measuring port of the shift control valve, the inlet of the pressure regulating valve is connected to the oil outlet of the fine filter element, and a pressure regulating nut is provided on the pressure regulating valve, and the pressure regulating nut is used to adjust the pressure of the pressure regulating valve.

[0009] Preferably, the valve body of the shift control valve is made of aluminum alloy, and the oil level gauge is installed on the box body by two hinged hollow bolts. The oil level gauge is used to display the hydraulic oil level height in the gearbox cavity.

[0010] Preferably, a distributor is fixedly connected to the box body by bolts, and the distributor is provided with an oil inlet and four oil outlets, wherein the oil inlet is connected to the outlet of the oil cooler, and the four oil outlets are respectively connected to the first gear clutch, the second gear clutch and the gear meshing part through oil pipes.

[0011] Preferably, the pressure relief oil circuit of the distributor is provided with a lubricating oil port connected to the lubricating oil circuit, and a cooling unit is provided on the pressure relief oil circuit and between the lubricating oil port and the outlet of the pressure regulating valve.

[0012] Preferably, a first-gear pressure oil pipe is provided at the top of the distributor, and a second-gear pressure oil pipe is fixedly connected to one side of the distributor, and a hydraulic brake is fixedly connected to one end of the box.

[0013] A hydraulic system of an electronically controlled two-speed high-speed box, comprising an electronic control system, a speed-changing hydraulic system and a lubrication system;

[0014] The electronic control system is used to control the pressure and flow of the clutch through an electric proportional valve, and to achieve communication and control of the gearbox through a wiring harness;

[0015] The speed change hydraulic system is used to control the pressure of the gear clutch and the gear shifting operation;

[0016] The lubrication system is used to provide good lubrication and cooling effects on the bearings, friction plates, and tooth surface meshing parts.

[0017] Preferably, the electronic control system includes an electronic control handle, a controller, an electric proportional valve, a speed sensor and a wiring harness. The electronic control handle is installed on a pillar of the entire machine cab, and the controller is installed on a base in the cab. The wiring harness connects the electronic control handle, the controller, the electric proportional valve and the speed sensor to achieve communication and control of the electronic control system. The speed change hydraulic system is provided with three pressure measuring points, namely, a main pressure measuring point, a first gear pressure measuring point and a second gear pressure measuring point. The main pressure measuring point detects the set pressure of the pressure regulating valve through a pressure sensor, the first gear pressure measuring point detects the working pressure of the first gear clutch through a first gear speed sensor, and the second gear pressure measuring point detects the working pressure of the second gear clutch through a second gear speed sensor.

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] 1. In the utility model, an electronically controlled two-speed high-speed gearbox and its hydraulic system can match the advantages of high speed and wide high-efficiency range of the motor. It has only a gear clutch but no directional clutch, is easy to operate, and has obvious advantages in energy saving and consumption reduction. The clutch oil pressure is adjusted to the working pressure range by a pressure regulating valve, and the pressure fluctuation is small, the pressure regulation response speed is fast, and the oil pressure measuring port is provided, which is convenient for pressure measurement. The pressure regulating valve has a compact structure and is integrated into the gearbox. The pipeline connection is convenient and convenient for the overall layout. The speed change valve adopts an embedded electric proportional valve structure. The clutch decompression curve is controlled by the PWM current output of the electronic control program to achieve a smooth engagement of the clutch during the gear shifting process and improve the gear shifting quality.

[0020] 2. In the utility model, the electronic control system forms a current curve with time as the horizontal axis and pressure as the vertical axis by comparing the current output value of the proportional valve through the electronic control program. The current curve mainly consists of the stages of clutch rapid oil filling, pressure boosting process, and dual plate combination. Compared with the traditional switch-type solenoid valve, the clutch pressure boosting curve can be controlled by the electronic control program. At the same time, the deviation of factors such as temperature and oil viscosity is comprehensively considered to correct the pressurization curve. In the speed change hydraulic system, the sealing ring on the clutch piston adopts an L-shaped structure, and the sealing lip adopts an arc-shaped optimized design, which has good sealing performance, ensures the inner cavity pressure of the clutch, and has good pressure holding performance. Wear-resistant composite materials are used to adapt to the axial reciprocating motion of the piston during the frequent engagement and separation of the clutch, and have good wear resistance. It is suitable for harsh working conditions such as high load, high temperature, and continuous operation of the loader. The electronically controlled second-speed high-speed box can meet the input requirements of the motor at high speed, can meet the working pressure of the clutch under conditions of high speed and large centrifugal force, and provide good cooling and lubrication for the clutch pack, bearings, and tooth surface meshing.

[0021] 3. In the utility model, the gearbox is provided with two working gears, and the forward and reverse switching gears are realized by the forward and reverse rotation of the motor. The input of the gearbox is a unidirectional input, and the input end face gear flange adopts an end face gear structure. The output end adopts a front and rear two-way flange output, and the output end face gear flange adopts an end face gear structure. It has large torque transmission and good stability, and is easy to install on the whole machine, meeting the requirements of the whole machine to realize front and rear four-wheel drive. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a hydraulic principle diagram of a three-dimensional diagram of an electronically controlled second-speed high-speed box of the utility model;

[0023] Figure 2 This is a front end axial view of an electronically controlled two-speed high-speed box of the utility model;

[0024] Figure 3 This is a rear end axle view of an electronically controlled two-speed high-speed box of the utility model;

[0025] Figure 4 This is a schematic diagram of the structure of a pressure regulating valve of an electronically controlled second-speed high-speed box of the utility model;

[0026] Figure 5 The utility model is a hydraulic system diagram of an electronically controlled two-speed high-speed box.

[0027] In the figure:

[0028] 1. Box; 2. Coarse filter element; 3. Speed ​​pump; 4. Fine filter element; 5. Pressure regulating valve; 6. Oil cooler; 7. Lubrication system; 8. First gear electric proportional valve; 9. Second gear electric proportional valve; 10. Shift control valve; 11. First gear clutch; 12. Second gear clutch; 13. Main pressure measuring point; 14. First gear pressure measuring point; 15. Second gear pressure measuring point; 16. Transmission; 17. Distributor; 18. Pressure oil outlet; 19. Valve inlet; 20. Speed ​​sensor; 21. Oil level gauge; 22. Oil suction port; 23. Output end face gear flange; 24. Input end face gear flange; 25. Hydraulic brake; 26. First gear pressure oil pipe; 27. Lubricating oil port; 28. Overflow oil outlet; 29. ​​Second gear pressure oil pipe; 30. Pressure regulating nut; 31. Clutch; 32. Electronic control system; 33. Speed ​​hydraulic system. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the implementation regulations described are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] Reference Figure 1 - Figure 5 As shown: an electronically controlled two-speed high-speed box, including a box body 1, a coarse filter element 2, a speed pump 3, a fine filter element 4, a pressure regulating valve 5, an oil cooler 6, a shift control valve 10, a gearbox 16, a clutch 31 and an oil level gauge 21, and also includes a shift motor, the shift motor is used to drive the speed pump 3 to work, the high-speed motor matched with the electronically controlled two-speed high-speed box is connected to the input end of the gearbox 16 through a reduction device, the input end of the gearbox 16 adopts a face gear structure, and the output end has front and rear bidirectional outputs, both of which adopt a face gear structure; the oil level gauge 21 is installed on the box body 1 through two hinged hollow bolts, and the oil level gauge 21 is used to display the hydraulic oil level height of the inner cavity of the gearbox 16;

[0031] like Figure 2As shown, the structure of the electronically controlled two-speed high-speed box, the pressure regulating valve 5 and the shift control valve 10 are integrated and installed on the gearbox 16, the coarse filter element 2 is installed at the bottom of the box body 1, and the speed pump 3 is connected to the oil outlet of the coarse filter element 2 through the oil suction port 22 set at the oil inlet, and the outlet of the speed pump 3 is connected to the fine filter element 4; the filtration accuracy of the fine filter element 4 is higher than that of the coarse filter element 2, and a bypass safety valve is built in. When the oil is contaminated or the cleanliness is poor, the oil difference between the inlet and outlet of the fine filter element 4 increases. When the pressure difference reaches the set pressure difference, the bypass safety valve opens to play a safety role, but the oil filtering function fails. For this reason, a pressure alarm is set on the oil filter. When the pressure difference between the oil inlet and the oil outlet of the oil filter exceeds the set value, the pressure alarm alarms;

[0032] like Figure 2 and Figure 3 As shown, the clutch 31 includes a clutch housing, a friction plate, a backing plate, a piston, a sealing ring, a return spring, a one-way valve, a retaining ring and other parts. The clutch 31 includes a first-gear clutch 11 and a second-gear clutch 12. The clutch 31 adopts a wear-resistant composite material. A sealing ring is installed on the piston in the clutch 31. The sealing ring adopts an L-shaped structure, and the sealing lip on the clutch 31 adopts an arc-shaped optimized design, which has good sealing performance and ensures the inner cavity pressure of the clutch 31. The wear-resistant composite material is adopted to adapt to the axial reciprocating motion of the piston during the frequent engagement and separation of the clutch 31, and has good wear resistance; under the control of the shift control valve 10, the engagement and separation of the clutch 31 are achieved by the on-off of the hydraulic oil. When the oil cylinder body of the clutch 31 is filled with pressure oil, the friction plate and the backing plate are engaged, and the clutch 31 is engaged to transmit power. On the contrary, when the clutch 31 is drained, the friction plate and the backing plate are separated, and the clutch 31 cuts off the power transmission;

[0033] like Figure 4 As shown, the pressure regulating valve 5 is mainly composed of a pressure regulating valve core, a valve body, a spring, an adjusting gasket, a pressure regulating nut 30 and other parts. The two ends of the pressure regulating valve 5 are respectively provided with a valve inlet 19, a pressure oil outlet 18 and an overflow oil outlet 28. The valve inlet 19 is fixedly connected to the outlet of the fine filter element 4 through a pipeline, the pressure oil outlet 18 is fixedly connected to the shift control valve 10 through a pipeline, and the overflow oil outlet 28 is connected to the oil inlet of the oil cooler 6 through a pipeline. The oil inlet of the shift control valve 10 is connected to the pressure regulating valve 5. The hydraulic oil flows from the gear shift control valve 10 to the pressure regulating valve 5. The outlet of the pump 3 flows into the pressure regulating valve 5, and the outlet of the pressure regulating valve 5 is connected to the shift control valve 10. After the hydraulic oil reaches the set pressure, the pressure regulating valve 5 opens, and the overflowed hydraulic oil enters the inner cavity of the box body 1 through the oil drain hole; under the regulation of the pressure regulating valve 5, the hydraulic oil enters the shift control valve 10 through the pressure oil outlet 18, and the overflowed hydraulic oil enters the oil cooler 6 through the overflow oil outlet 28 for cooling. The oil outlet of the shift control valve 10 is connected to the first gear clutch 11 and the second gear clutch 12 through a hose respectively;

[0034] like Figure 2 and Figure 3 As shown, a distributor 17 is fixedly connected to the housing 1 by bolts, and the distributor 17 is provided with an oil inlet and four oil outlets, wherein the oil inlet is connected to the outlet of the oil cooler 6, and the four oil outlets are respectively connected to the first gear clutch 11, the second gear clutch 12 and the gear meshing part through oil pipes, so as to lubricate and cool the bearings, friction plates, gear meshing surfaces and other parts inside the gearbox 16 respectively; a first gear pressure oil pipe 26 is provided at the top of the distributor 17, and a second gear pressure oil pipe 29 is fixedly connected to one side of the distributor 17, and a hydraulic brake 25 is fixedly connected to one end of the housing 1; the pressure relief oil circuit of the distributor 17 is provided with a connecting lubrication oil pipe 26, and the second gear pressure oil pipe 29 is fixedly connected to one side of the distributor 17, and the hydraulic brake 25 is fixedly connected to one end of the housing 1; the pressure relief oil circuit of the distributor 17 is provided with a connecting lubrication oil pipe 26, and the second gear pressure oil pipe 29 is fixedly connected to the one side of the distributor 17, and the hydraulic brake 25 is fixedly connected to the ... side of the housing 1 The lubricating oil port 27 of the oil circuit, and the cooling unit is provided on the pressure relief oil circuit and between the lubricating oil port 27 and the outlet of the pressure regulating valve 5; the hydraulic oil enters the clutch 31 after the pressure is adjusted by the pressure regulating valve 5, and the overflowing hydraulic oil enters the oil cooler 6 through the overflow oil outlet 28, so as to realize the cooling of the hydraulic oil of the lubricating system 7, and the cooled hydraulic oil enters the distributor 17 through the lubricating oil port 27 through the pipeline, and the distributor 17 can reasonably distribute the hydraulic oil from the oil cooler 6 to the lubrication of different parts of the gearbox 16 through the built-in oil channel of the oil, so as to perform oil cooling and lubrication on key components such as bearings, friction plates, gear surfaces, etc.;

[0035] like Figure 1 As shown, the hydraulic oil from the pressure regulating valve 5 enters the shift control valve 10 through the pipeline. The shift control valve 10 includes a valve body, an electric proportional cartridge valve, a pressure measuring interface, etc. The valve body of the shift control valve 10 is made of aluminum alloy. A first-gear electric proportional valve 8 and a second-gear electric proportional valve 9 are installed on the valve body of the shift control valve 10. The control signal interface of the electric proportional valve is connected to the controller through a wiring harness. The connectors of the first-gear electric proportional valve 8 and the second-gear electric proportional valve 9 are connected to the controller through a wiring harness. Under the action of the electronic control program, the controller outputs a PWM current signal, and the pressure of the first-gear clutch 11 and the second-gear clutch 12 is controlled by the PWM current signal, thereby controlling the boost curve of the clutch 31 to achieve smooth shifting.

[0036] like Figure 1 - Figure 3 As shown, a speed sensor 20 is installed on one side of the housing 1. The speed sensor 20 is arranged in a one-to-one correspondence with the clutch 31, and the speed sensor 20 is used to detect the input speed and output speed of the corresponding clutch 31. The speed is calculated through a certain algorithm through the gear ratio of the meshing gear pair, and the speed of the output end gear of the clutch 31 is calculated. The speed of the input end of the clutch 31 is read by the output speed sensor 20 on the motor. The electronic control program uses a certain algorithm. When the input speed and output speed difference of the clutch 31 are within a certain range (when the speed difference is within the set speed difference range), the gearbox 16 realizes gear switching to ensure smoothness of gear shifting;

[0037] like Figure 2 and Figure 3 As shown, one end of the housing 1 is fixedly connected to an output end face gear flange 23, and the other end of the housing 1 is fixedly connected to an input end face gear flange 24. Both the input end face gear flange 24 and the output end face gear flange 23 adopt the structure of end face gears. Compared with the traditional disc flange, this structure has large torque transmission, good stability, and is easy to install and disassemble. The input end face gear flange 24 is connected to the motor, and the output end face gear flange 23 is connected to the output transmission shaft.

[0038] like Figure 1 and Figure 2 As shown, a main pressure measuring point 13 is provided on the pressure measuring port of the shift control valve 10, the inlet of the pressure regulating valve 5 is connected with the oil outlet of the fine filter element 4, and a pressure regulating nut 30 is provided on the pressure regulating valve 5, and the pressure regulating nut 30 is used to adjust the pressure of the pressure regulating valve 5; Figure 4 After the pressure of the pressure regulating valve 5 shown in the figure is adjusted, the hydraulic oil enters the shift control valve 10 through the pressure oil outlet 18, thereby realizing the engagement and disengagement of the clutch 31. The pressure is adjusted by the pressure regulating nut 30. Counterclockwise rotation increases the pressure, and vice versa, it reduces the set pressure. When the pressure regulating valve 5 is tested on a test bench, it is usually adjusted to the designed pressure range under certain flow conditions and fixed with the locking nut on the pressure regulating valve 5.

[0039] like Figure 1 - Figure 5 As shown, a hydraulic system of an electronically controlled two-speed high-speed gearbox includes an electronic control system 32, a speed-changing hydraulic system 33 and a lubrication system 7; the electronic control system 32 is used to control the pressure and flow of the clutch 31 through an electric proportional valve, and at the same time realizes the communication and control of the gearbox 16 through a wiring harness; the speed-changing hydraulic system 33 is used to control the pressure and shifting operation of the gear clutch 31; the lubrication system 7 is used to provide good lubrication and cooling for the bearings, friction plates, and tooth surface meshing parts, reduce energy loss, and take away harmful heat; the electronic control system 32 includes an electronic control handle, a controller, an electronic proportional valve, a speed sensor 20 and a wiring harness, the electronic control handle is installed on the column of the cab of the whole machine, the driver performs the shifting operation, and the controller is installed It is installed on the base in the cab to prevent exposure to the sun, rain and other environments. The electric proportional valve is installed on the valve body of the shift valve to control the pressure and flow of the clutch 31. The wiring harness connects the electric control handle, the controller, the electric proportional valve and the speed sensor 20 to realize the communication and control of the electronic control system 32. The speed change hydraulic system 33 is provided with three pressure measuring points, namely, the main pressure measuring point 13, the first gear pressure measuring point 14 and the second gear pressure measuring point 15. The main pressure measuring point 13 detects the set pressure of the pressure regulating valve 5 through the pressure sensor, the first gear pressure measuring point 14 detects the working pressure of the first gear clutch 11 through the first gear speed sensor, and the second gear pressure measuring point 15 detects the working pressure of the second gear clutch 12 through the second gear speed sensor.

[0040] Working principle of this embodiment: the utility model is provided with a one-way valve at the bottom of the clutch 31 oil cylinder body, the one-way valve comprises a valve body and a steel ball, the angle of the conical sealing surface of the valve body is determined by optimizing the design of the steel ball mass, the maximum speed, the oil pressure and the oil viscosity, etc., and through matching calculation and optimization design, it is ensured that during the pressure building process of the clutch 31, the steel ball quickly combines with the conical surface, the one-way valve is closed, and the clutch 31 is pressurized. During the pressure relief process of the clutch 31, the one-way valve steel ball is quickly disengaged under the action of centrifugal force, and the one-way valve is opened to achieve fast oil leakage of the clutch 31, thereby avoiding the sliding friction between the friction plate and the backing plate during the disengagement process, ensuring the high input speed of the electric second gear box while affecting the service life of the clutch 31 (the centrifugal force generated by the oil in the inner cavity of the clutch 31 during high-speed rotation increases to generate axial force, and the opening of the one-way valve is delayed during the oil leakage process, resulting in the friction plate and the backing plate not being able to separate quickly and generating sliding friction work, causing temperature rise, and easily causing the friction plate to warp and deform);

[0041] The utility model also provides a clutch combination control method, using the above-mentioned electronically controlled two-speed high-speed gearbox, the main implementation steps are: the structure of the gearbox 16 adopts the structure of a wet friction plate clutch, which is characterized by only a gear clutch package and no direction clutch package, and is used in conjunction with a travel drive motor to achieve reversing through the forward and reverse rotation of the motor. The structural principle of the gearbox 16 is as follows: Figure 1 As shown, the gearbox 16 shifts gears through an electronic control handle. After the driver operates the handle, the gear shift signal transmits information to the controller through CAN communication. The electronic control program outputs a PWM current signal through a certain electronic control algorithm to control the electric proportional valve on the speed change valve, thereby achieving gear switching. This solves the problem that during the gear shifting process, the large speed difference between the friction plate and the pad causes gear shifting shock, affects the driving experience of the entire machine, and affects the service life of the gearbox 16.

[0042] In the utility model, an electronically controlled two-speed high-speed gearbox and its hydraulic system can match the advantages of high speed and wide high-efficiency range of the motor. It has only a gear clutch but no directional clutch, is easy to operate, and has obvious advantages in energy saving and consumption reduction. The oil pressure of the clutch 31 is adjusted to the working pressure range through the pressure regulating valve 5, with small pressure fluctuation and fast pressure regulation response speed. It is equipped with a pressure measuring port, which is convenient for pressure measurement. The pressure regulating valve 5 has a compact structure and is integrated into the gearbox 16. The pipeline connection is convenient and convenient for the overall layout. The speed change valve adopts an embedded electric proportional valve structure. The pressure building curve of the clutch 31 is controlled through the PWM current output of the electronic control program, so as to realize the smooth engagement of the clutch 31 during the gear shifting process and improve the gear shifting quality.

[0043] By setting the electronic control system 32, the electronic control system 32 forms a current curve with time as the horizontal axis and pressure as the vertical axis through the electronic control program to the current output value of the proportional valve. The current curve mainly consists of the clutch 31 fast oil filling, pressure increase process, dual plate combination and other stages. Compared with the traditional switch type solenoid valve, the clutch 31 pressure increase curve can be controlled by the electronic control program. At the same time, the deviation of factors such as temperature and oil viscosity is comprehensively considered to correct the pressurization curve. In the speed change hydraulic system 33, the sealing ring on the clutch 31 piston adopts an L-shaped structure, and the sealing lip adopts an arc-shaped optimized design, which has good sealing performance, ensures the inner cavity pressure of the clutch 31, and has good pressure holding performance. Wear-resistant composite materials are used to adapt to the axial reciprocating motion of the piston during the frequent engagement and separation of the clutch 31, and have good wear resistance. It is suitable for severe working conditions such as high load, high temperature, and continuous operation of the loader; the electronically controlled second-speed high-speed box can meet the input requirements of the motor at high speed, can meet the working pressure of the clutch 31 under the conditions of high speed and large centrifugal force, and provide good cooling and lubrication for the clutch pack, bearings, tooth surface meshing, etc.;

[0044] At the same time, the gearbox 16 has two working gears, and the forward and reverse switching gears are realized by the forward and reverse rotation of the motor. The input of the gearbox 16 is a unidirectional input, and the input end face gear flange 24 adopts an end face gear structure. The output end adopts a front and rear two-way flange output, and the output end face gear flange 23 adopts an end face gear structure. It has large torque transmission and good stability, and is easy to install on the whole machine, meeting the requirements of the whole machine to realize front and rear four-wheel drive.

[0045] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. An electronically controlled two-speed high-speed gearbox, characterized in that: The invention comprises a housing (1), a coarse filter element (2), a speed change pump (3), a fine filter element (4), a pressure regulating valve (5), an oil cooler (6), a shift control valve (10), a gearbox (16), a clutch (31) and an oil level gauge (21), wherein the pressure regulating valve (5) and the shift control valve (10) are integrally mounted on the gearbox (16), the coarse filter element (2) is mounted on the bottom of the housing (1), the speed change pump (3) is connected to the oil outlet of the coarse filter element (2) via an oil suction port (22) arranged at the oil inlet, and the oil level gauge (21) is connected to the oil outlet of the coarse filter element (2) via an oil suction port (22) arranged at the oil inlet. The outlet of the variable speed pump (3) is connected to the fine filter element (4); the clutch (31) comprises a first gear clutch (11) and a second gear clutch (12); the clutch (31) is made of a wear-resistant composite material; the sealing ring on the piston of the clutch (31) is of an L-shaped structure; and the sealing lip on the clutch (31) is of an arc-shaped structure; the two ends of the pressure regulating valve (5) are respectively provided with a valve inlet (19), a pressure oil outlet (18) and an overflow oil outlet (28); the valve inlet (19) is connected to the pressure regulating valve (5); The oil outlet (18) is fixedly connected to the outlet of the fine filter element (4) through a pipeline, the pressure oil outlet (18) is fixedly connected to the shift control valve (10) through a pipeline, the overflow oil outlet (28) is connected to the oil inlet of the oil cooler (6) through a pipeline, the oil inlet of the shift control valve (10) is connected to the pressure regulating valve (5), and the oil outlet of the shift control valve (10) is respectively connected to the first gear clutch (11) and the second gear clutch (12) through a hose, and a first gear electric proportional clutch is installed on the valve body of the shift control valve (10). A first-gear electric proportional valve (8) and a second-gear electric proportional valve (9), the connectors of the first-gear electric proportional valve (8) and the second-gear electric proportional valve (9) being connected to a controller via a wiring harness, and the pressure of the first-gear clutch (11) and the second-gear clutch (12) being controlled via a PWM current signal, a speed sensor (20) being installed on one side of the housing (1), the speed sensor (20) being arranged in a one-to-one correspondence with the clutch (31), and the speed sensor (20) being used to detect the input speed and output speed of the corresponding clutch (31).

2. The electronically controlled second-speed high-speed gearbox according to claim 1, characterized in that: An output end face gear flange (23) is fixedly connected to one end of the housing (1), and an input end face gear flange (24) is fixedly connected to the other end of the housing (1); both the input end face gear flange (24) and the output end face gear flange (23) adopt the structure of end face gears; the input end face gear flange (24) is connected to the motor, and the output end face gear flange (23) is connected to the output transmission shaft.

3. The electronically controlled second-speed high-speed gearbox according to claim 1, characterized in that: A main pressure measuring point (13) is provided on the pressure measuring port of the shift control valve (10), the inlet of the pressure regulating valve (5) is connected to the oil outlet of the fine filter element (4), and a pressure regulating nut (30) is provided on the pressure regulating valve (5), and the pressure regulating nut (30) is used to adjust the pressure of the pressure regulating valve (5).

4. The electronically controlled second-speed high-speed gearbox according to claim 1, characterized in that: The valve body of the shift control valve (10) is made of an aluminum alloy material. The oil level gauge (21) is mounted on the housing (1) via two hinged hollow bolts. The oil level gauge (21) is used to display the height of the hydraulic oil level in the inner cavity of the gearbox (16).

5. The electronically controlled second-speed high-speed gearbox according to claim 1, characterized in that: A distributor (17) is fixedly connected to the box body (1) by means of bolts, and the distributor (17) is provided with an oil inlet and four oil outlets, wherein the oil inlet is connected to the outlet of the oil cooler (6), and the four oil outlets are respectively connected to the first gear clutch (11), the second gear clutch (12) and the gear meshing portion through oil pipes.

6. The electronically controlled second-speed high-speed gearbox according to claim 5, characterized in that: The pressure relief oil circuit of the distributor (17) is provided with a lubricating oil port (27) connected to the lubricating oil circuit, and a cooling unit is provided on the pressure relief oil circuit and between the lubricating oil port (27) and the outlet of the pressure regulating valve (5).

7. The electronically controlled second-speed high-speed gearbox according to claim 5, characterized in that: A first-gear pressure oil pipe (26) is provided at the top of the distributor (17), and a second-gear pressure oil pipe (29) is fixedly connected to one side of the distributor (17), and a hydraulic brake (25) is fixedly connected to one end of the box (1).

8. A hydraulic system for an electronically controlled second-speed high-speed gearbox, characterized in that: An electronically controlled two-speed high-speed gearbox according to any one of claims 1 to 7, comprising an electronic control system (32), a speed change hydraulic system (33) and a lubrication system (7); The electronic control system (32) is used to control the pressure and flow of the clutch (31) through an electric proportional valve, and to achieve communication and control of the gearbox (16) through a wiring harness; The speed change hydraulic system (33) is used to control the pressure of the gear clutch (31) and the gear shifting operation; The lubrication system (7) is used to provide good lubrication and cooling effects on the bearings, friction plates, and tooth surface meshing parts.

9. The hydraulic system of the electronically controlled second-speed high-speed box according to claim 8, characterized in that: The electric control system (32) comprises an electric control handle, a controller, an electric proportional valve, a speed sensor (20) and a wiring harness. The electric control handle is mounted on a column of a cab of the whole machine, and the controller is mounted on a base in the cab. The wiring harness connects the electric control handle, the controller, the electric proportional valve and the speed sensor (20) to achieve communication and control of the electric control system (32). The speed change hydraulic system (33) is provided with three pressure measuring points, namely a main pressure measuring point (13), a first gear pressure measuring point (14) and a second gear pressure measuring point (15). The main pressure measuring point (13) detects the set pressure of the pressure regulating valve (5) through a pressure sensor, the first gear pressure measuring point (14) detects the working pressure of the first gear clutch (11) through a first gear speed sensor, and the second gear pressure measuring point (15) detects the working pressure of the second gear clutch (12) through a second gear speed sensor.

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