Tractor power shift transmission system and tractor

Abstract

The invention provides a tractor power shift transmission system and a tractor. A tractor power shift transmission system comprises: a power high and low unit, a power shuttle unit, a main and auxiliary speed change unit, a hydraulic transfer case unit, a PTO unit, a central transmission unit, a PTO constant mesh unit, a double-speed four-wheel drive unit, a brake unit, and a final transmission unit. The power high and low unit is transmission-connected with the power shuttle unit, the power shuttle unit is transmission-connected with the main and auxiliary speed change unit, the main and auxiliary speed change unit is transmission-connected with the hydraulic transfer case unit, the PTO unit, and the central transmission unit, the PTO constant mesh unit, the double-speed four-wheel drive unit, and the final transmission unit are all connected with the central transmission unit, the double-speed four-wheel drive unit is installed in a gearbox housing, the brake unit is installed between the central transmission unit and the final transmission unit, and the PTO unit has multi-speed forward and reverse functions.

Description

Technical Field

[0001] The invention relates to the technical field of tractor power shifting, and in particular to a tractor power shifting transmission system and a tractor. Background Art

[0002] As an important part of agricultural machinery, tractors play the role of a powerful assistant for agricultural friends, and the tractor power shift transmission system is a key part of the tractor's performance and efficiency. In traditional tractors, mechanical shift transmission systems are mostly used, but with the advancement of technology and the continuous changes in demand, people have put forward higher requirements for the performance and efficiency of tractors, so the application prospects of tractor power shift transmission systems have attracted much attention.

[0003] PTO operation of the tractor is its commonly used working mode, especially in the paddy field operation environment in the south. A variety of PTO speeds can be matched with different agricultural machinery and are suitable for various operation modes. Different from the traditional PTO speed mode, the demand for PTO reverse and synchronous power output functions is gradually increasing.

[0004] During paddy field operations in the south, due to the small size of the land, the turning radius becomes an important indicator for judging the core competitiveness of tractors. Therefore, the high-speed reversing function that can reduce the turning radius has become the direction for tractor companies to benchmark against international standards. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a tractor power shift transmission system and a tractor in view of the deficiencies in the prior art.

[0006] The technical solution of the present invention to solve the above technical problems is as follows: A tractor power shift transmission system, comprising: a power high and low unit, a power shuttle unit, a main and auxiliary speed change unit, a hydraulic transfer case unit, a PTO unit, a central transmission unit, a PTO constant meshing unit, a double-speed four-wheel drive unit, a brake unit, and a final transmission unit, wherein the power high and low unit is transmission-connected to the power shuttle unit, the power shuttle unit is transmission-connected to the main and auxiliary speed change unit, the main and auxiliary speed change unit is transmission-connected to the hydraulic transfer case unit, the PTO unit and the central transmission unit, the PTO constant meshing unit, the double-speed four-wheel drive unit, and the final transmission unit are all connected to the central transmission unit, the double-speed four-wheel drive unit is installed in a gearbox housing, the brake unit is installed between the central transmission unit and the final transmission unit, and the PTO unit has multi-speed forward and reverse functions.

[0007] The beneficial effects of adopting the technical solution of the present invention are: the PTO unit has multi-speed forward and reverse functions, more speed options, and a wider range of machine matching options. A variety of PTO speeds can be matched with different agricultural machinery and are suitable for various operation modes. The double-speed four-wheel drive unit is arranged in the gearbox housing. Compared with the traditional arrangement in the rear axle housing, the length of the drive shaft connected to the front axle is reduced. The conventional arrangement of the two shafts with a support seat in the middle can use a shaft directly connected to the front axle, which has higher transmission performance and efficiency and lower cost. It solves the problem of people's higher requirements for tractor performance and efficiency, solves the problem of PTO operation needing to match a variety of agricultural machinery and solves the problem of large turning radius of tractors.

[0008] Furthermore, a planetary mechanism is installed in the power high and low unit, and the power high and low unit is connected to a power high and low unit electronic control system for controlling an oil circuit.

[0009] The beneficial effects of adopting the above further technical solution are: the electric control system of the power high and low unit controls the oil circuit, acts on the planetary mechanism, and uses the planetary principle to achieve deceleration and speed increase, thereby satisfying the high and low gear switching. The electric control system controls the oil circuit, acts on the planetary mechanism to achieve high and low gear switching. Reduce costs and reduce space occupancy.

[0010] Furthermore, the power high and low unit is connected to the engine; the power high and low unit is transmission-connected to the power shuttle unit through internal and external splines, and the power shuttle unit is transmission-connected to the main and auxiliary speed change units through internal and external splines.

[0011] The beneficial effect of adopting the above further technical solution is that the engine is connected to the power high and low unit, which is convenient for transmitting power to the power high and low unit. Each unit is connected by internal and external spline transmission to prevent relative rotation, achieve synchronous rotation, and improve system stability and reliability.

[0012] Furthermore, a forward and reverse wet clutch is installed in the power shuttle unit, and the power shuttle unit is connected to a power shuttle unit electronic control system for controlling an oil circuit.

[0013] The beneficial effects of adopting the above further technical solution are: the power shuttle unit is equipped with a forward and reverse wet clutch, the high-pressure oil circuit realizes engagement and disengagement, and the power shuttle unit electronic control system controls the oil circuit to realize gear switching, which improves the performance and efficiency of the tractor and makes the operating experience more comfortable. The electronic control system controls the oil circuit, and the forward and reverse clutch realizes the gear switching.

[0014] Furthermore, the main and auxiliary transmission units have 6-speed main transmission and 2-speed auxiliary transmission functions, the main transmission of the main and auxiliary transmission units is shifted by a synchronizer, and the auxiliary transmission of the main and auxiliary transmission units is shifted by a clutch sleeve.

[0015] The beneficial effects of adopting the above further technical solution are: 6-speed main transmission, synchronizer shifting, 2-speed auxiliary transmission, and clutch sleeve shifting, which makes the shifting smoother and easier to operate, less prone to tooth knocking, and longer gear service life.

[0016] Furthermore, the housing of the hydraulic transfer case unit is integrated with the rear axle housing, the hydraulic transfer case unit is connected to a gear pump, and the gears of the hydraulic transfer case unit are helical gears.

[0017] The beneficial effects of adopting the above-mentioned further technical solution are: the hydraulic transfer case unit drives the gear pump to provide power for the power shift control valve and the steering lifting system. The gears of the hydraulic transfer case unit adopt helical gear transmission, which is more efficient than the traditional straight tooth transmission, runs smoothly, and reduces the risk of abnormal noise. The housing of the hydraulic transfer case unit is integrated into the rear axle housing, which is more convenient to install. At the same time, the hydraulic transfer case unit has forced lubrication to reduce the failure risk of bearing gears at high speeds.

[0018] Furthermore, the PTO unit has a 3-speed forward rotation and a 1-speed reverse rotation function, the PTO unit is installed in the rear central transmission, and a small bevel gear shaft is provided in the PTO unit.

[0019] The beneficial effects of adopting the above further technical solution are: PTO speed 3+1, three speeds 540 / 540E / 1000, another speed is PTO reverse, PTO unit 4-speed PTO, compared with the traditional 2-speed ratio, there are more speed options, and the machine matching selection is wider. The PTO unit is arranged in the rear central transmission, using the existing small bevel gear shaft, and the layout is compact. Compared with the traditional PTO arranged at the rear end of the rear axle housing, the axial length of the transmission chassis is greatly reduced, saving space and weight for the layout of the whole machine, and solving the problem that PTO operations need to match a variety of agricultural machinery. A variety of PTO speeds can be matched with different agricultural machinery and are suitable for various operation modes.

[0020] Furthermore, a wet clutch is installed in the double-speed four-wheel drive unit, and the double-speed four-wheel drive unit has two-wheel drive, four-wheel drive and double-speed functions. The double-speed four-wheel drive unit adopts three-way oil circuit control of the double-speed four-wheel drive unit electronic control system; the wet clutch in the double-speed four-wheel drive unit is a normally engaged wet clutch, and the wet clutch in the double-speed four-wheel drive unit is installed in the gearbox housing.

[0021] The beneficial effects of adopting the above further technical solution are: the double-speed four-wheel drive unit provides power for the front drive axle, and realizes two-wheel drive, four-wheel drive and double-speed modes through a wet clutch. The double-speed four-wheel drive unit adopts a three-way oil circuit control of the double-speed four-wheel drive unit electronic control system. Compared with the traditional two-way oil circuit control, the whole machine performance is better. The traditional arrangement of the two-wheel drive function has no oil circuit control, the default clutch is disengaged, and the power cannot be transmitted to the front axle. The double-speed four-wheel drive unit defaults to clutch engagement, and the front axle is a four-wheel drive function in the flameout state, which can better realize ramp parking. The front axle is quickly braked after the flameout, which can not only reduce the turning radius of the tractor, but also the gear switching is realized by the wet clutch. The operating experience is more comfortable. The wet clutch of the double-speed four-wheel drive unit is arranged in the gearbox housing. Compared with the traditional arrangement in the rear axle housing, the length of the drive shaft connected to the front axle is reduced. The conventional arrangement of the two shafts with a support seat in the middle, the double-speed four-wheel drive unit can use a shaft directly connected to the front axle, which has higher transmission performance and efficiency and lower cost. The gear at the rear end of the input shaft of the double-speed four-wheel drive unit engages with the gear at the front end of the central transmission unit to achieve power transmission, and this power is transmitted to the front axle of the tractor through the wet clutch in the double-speed four-wheel drive unit. The electronic control system controls the three-way oil circuit, which acts on the wet clutch to achieve double-speed, four-wheel drive, and two-wheel drive. The traditional two-way oil circuit control and three-way control are better for the performance of the whole machine. Solve the problem of large turning radius of tractors.

[0022] Furthermore, the brake unit has a built-in brake, a brake pad is installed in the brake unit, the central transmission unit is connected to the final transmission unit through left and right half shafts, and the brake pad is connected to the left and right half shafts through a spline.

[0023] The beneficial effect of adopting the above further technical solution is that the brake of the brake unit is built-in, which avoids the risk of oil leakage compared with the traditional external brake. The central transmission unit transmits power to the final transmission unit through the left and right half shafts, thereby driving the rear wheels to operate.

[0024] In addition, the present invention also provides a tractor, comprising a tractor power shift transmission system as described in any one of the above.

[0025] The beneficial effects of adopting the technical solution of the present invention are: the PTO unit has multi-speed forward and reverse functions, more speed options, and a wider range of machine matching options. A variety of PTO speeds can be matched with different agricultural machinery and are suitable for various operation modes. The double-speed four-wheel drive unit is arranged in the gearbox housing. Compared with the traditional arrangement in the rear axle housing, the length of the drive shaft connected to the front axle is reduced. The conventional arrangement of the two shafts with a support seat in the middle can use a shaft directly connected to the front axle, which has higher transmission performance and efficiency and lower cost. It solves the problem of people's higher requirements for tractor performance and efficiency, solves the problem of PTO operation needing to match a variety of agricultural machinery and solves the problem of large turning radius of tractors.

[0026] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is one of the structural schematic diagrams of the tractor power shift transmission system provided by an embodiment of the present invention.

[0028] Figure 2 for Figure 1 Structural schematic diagram of the power high and low units in the structure shown.

[0029] Figure 3 for Figure 1 Schematic diagram of the structure of the power shuttle unit in the structure shown.

[0030] Figure 4 for Figure 1 Schematic diagram of the structure of the main and auxiliary speed change units in the structure shown.

[0031] Figure 5 for Figure 1 Schematic diagram of the structure of the hydraulic transfer case unit in the structure shown.

[0032] Figure 6 for Figure 1 Schematic diagram of the structure of the PTO unit in the structure shown.

[0033] Figure 7 for Figure 1 Schematic diagram of the structure of the central transmission unit in the structure shown.

[0034] Figure 8 for Figure 1 Schematic diagram of the structure of the PTO constantly engaged unit in the structure shown.

[0035] Fig. 9 for Figure 1 Schematic diagram of the structure of the double-speed four-wheel drive unit in the structure shown.

[0036] Fig.10 The second structural schematic diagram of the tractor power shift transmission system provided by the embodiment of the present invention.

[0037] Fig.11 for Fig.10 Schematic diagram of the structure of the central transmission unit in the structure shown.

[0038] Fig.12 for Fig.10 Schematic diagram of the structure of the brake unit in the structure shown.

[0039] Fig.13 for Fig.10 Schematic diagram of the structure of the final drive unit in the structure shown.

[0040] Explanation of the accompanying figures: 1. Power high and low unit; 2. Power shuttle unit; 3. Main and auxiliary speed change unit; 4. Hydraulic transfer case unit; 5. PTO unit; 6. Central transmission unit; 7. PTO constant engagement unit; 8. Double-speed four-wheel drive unit; 9. Braking unit; 10. Final drive unit. DETAILED DESCRIPTION

[0041] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention but not to limit the scope of the present invention.

[0042] like Figures 1 to 13 As shown, an embodiment of the present invention provides a tractor power shift transmission system, comprising: a power high and low unit 1, a power shuttle unit 2, a main and auxiliary speed change unit 3, a hydraulic transfer case unit 4, a PTO unit 5, a central transmission unit 6, a PTO constant meshing unit 7, a double-speed four-wheel drive unit 8, a brake unit 9, and a final transmission unit 10, wherein the power high and low unit 1 is transmission-connected with the power shuttle unit 2, the power shuttle unit 2 is transmission-connected with the main and auxiliary speed change unit 3, the main and auxiliary speed change unit 3 is transmission-connected with the hydraulic transfer case unit 4, the PTO unit 5 and the central transmission unit 6, the PTO constant meshing unit 7, the double-speed four-wheel drive unit 8, and the final transmission unit 10 are all connected with the central transmission unit 6, the double-speed four-wheel drive unit 8 is installed in a gearbox housing, the brake unit 9 is installed between the central transmission unit 6 and the final transmission unit 10, and the PTO unit 5 has multi-speed forward and reverse functions.

[0043] The beneficial effects of adopting the technical solution of the present invention are: the PTO unit has multi-speed forward and reverse functions, more speed options, and a wider range of machine matching options. A variety of PTO speeds can be matched with different agricultural machinery and are suitable for various operation modes. The double-speed four-wheel drive unit is arranged in the gearbox housing. Compared with the traditional arrangement in the rear axle housing, the length of the drive shaft connected to the front axle is reduced. The conventional arrangement of the two shafts with a support seat in the middle can use a shaft directly connected to the front axle, which has higher transmission performance and efficiency and lower cost. It solves the problem of people's higher requirements for tractor performance and efficiency, solves the problem of PTO operation needing to match a variety of agricultural machinery and solves the problem of large turning radius of tractors.

[0044] The embodiment of the present invention provides a tractor power shift transmission system, which can be a tractor power shift transmission system structure, and has the following main functions: power high and low (realized by a power high and low unit, using a power high and low unit electronic control system to control the oil circuit, acting on a planetary mechanism to achieve high and low gear switching), power reversing (realized by a power reversing unit, also known as a power shuttle unit, the power shuttle unit electronic control system controls the oil circuit, and the forward and reverse clutch achieves gear switching), wet PTO, PTO speed 3+1 (realized by a PTO unit and a PTO constant meshing unit, a total of 4-speed PTO, 1 of which has a reverse speed), double-speed reversing, wet four-wheel drive, wet two-wheel drive (realized by a double-speed four-wheel drive unit, using a double-speed four-wheel drive unit electronic control system to control three oil circuits, acting on a wet clutch, achieving double speed, four-wheel drive, and two-wheel drive, traditional two-way oil circuit control, three-way control has better overall machine performance), solves the problem of people's higher requirements for tractor performance and efficiency, solves the problem that PTO operations need to match a variety of agricultural machinery, and solves the problem of a large turning radius of the tractor.

[0045] Specifically, the power high and low unit 1 may include: a first shell, a first transmission shaft and a planetary mechanism, wherein the planetary mechanism and the first transmission shaft are rotatably installed in the first shell, one end of the first transmission shaft is connected to the engine, the other end of the first transmission shaft is connected to the power shuttle unit 2, and the planetary mechanism is connected to the middle part of the first transmission shaft.

[0046] The power shuttle unit 2 may include: a second housing, a second transmission shaft, a third transmission shaft, a fourth transmission shaft, and a forward and reverse wet clutch. The second transmission shaft, the third transmission shaft, and the fourth transmission shaft are all rotatably mounted in the second housing. The forward and reverse wet clutch is mounted on the second transmission shaft. The second transmission shaft is connected to the first transmission shaft of the power high and low unit 1. The third transmission shaft and the fourth transmission shaft are both connected to the main and auxiliary speed change unit 3. The second transmission shaft is provided with a first gear and a second gear, the third transmission shaft is provided with a third gear, and the fourth transmission shaft is provided with a fourth gear and a fifth gear; the second gear is meshed with the third gear, and the third gear is meshed with the fifth gear.

[0047] The main and auxiliary speed change unit 3 may include: a third housing, a fifth transmission shaft, a sixth transmission shaft, a seventh transmission shaft and an eighth transmission shaft. The fifth transmission shaft, the sixth transmission shaft, the seventh transmission shaft and the eighth transmission shaft are all rotatably installed in the third housing. The two ends of the fifth transmission shaft are respectively connected to the second transmission shaft of the power shuttle unit 2 and the hydraulic transfer case unit 4, the sixth transmission shaft is connected to the third transmission shaft of the power shuttle unit 2, the two ends of the seventh transmission shaft are respectively connected to the fourth transmission shaft of the power shuttle unit 2 and the PTO unit 5, and the eighth transmission shaft is connected to the PTO unit 5.

[0048] The fifth transmission shaft is provided with a sixth gear, a seventh gear, an eighth gear, a ninth gear, a tenth gear and an eleventh gear, the sixth transmission shaft is provided with a twelfth gear, a thirteenth gear, a fourteenth gear, a fifteenth gear, a sixteenth gear and a seventeenth gear, the seventh transmission shaft is provided with an eighteenth gear, a nineteenth gear, a twentieth gear, a twenty-first gear, a twenty-second gear and a twenty-third gear, the eighth transmission shaft is provided with a twenty-fourth gear and a twenty-fifth gear, the sixth gear is meshed with the twelfth gear, the seventh gear is meshed with the thirteenth gear, the eighth gear is meshed with the fourteenth gear, the ninth gear is meshed with the fifteenth gear, the tenth gear is meshed with the sixteenth gear, the eleventh gear is meshed with the seventeenth gear, the twelfth gear is meshed with the eighteenth gear, the thirteenth gear is meshed with the nineteenth gear, the fourteenth gear is meshed with the twentieth gear, the fifteenth gear is meshed with the twenty-first gear, the sixteenth gear is meshed with the twenty-second gear, the seventeenth gear is meshed with the twenty-third gear, and the twenty-third gear is meshed with the twenty-fifth gear.

[0049] The hydraulic transfer case unit 4 may include: a fourth housing, a first gear shaft and a second gear shaft, the first gear shaft and the second gear shaft are both rotatably mounted in the fourth housing, the first gear shaft is connected to the fifth transmission shaft of the main and auxiliary speed change unit 3, and the second gear shaft is connected to the seventh transmission shaft of the main and auxiliary speed change unit 3 through gears.

[0050] The PTO unit 5 may include: a fifth housing, a ninth transmission shaft, a tenth transmission shaft and an eleventh transmission shaft, wherein the ninth transmission shaft, the tenth transmission shaft and the eleventh transmission shaft are all rotatably mounted in the fifth housing, the two ends of the ninth transmission shaft are respectively connected to the seventh transmission shaft of the primary and secondary transmission unit 3 and the central transmission unit 6, and the two ends of the tenth transmission shaft are respectively connected to the eighth transmission shaft of the primary and secondary transmission unit 3 and the central transmission unit 6. The ninth transmission shaft is provided with a twenty-sixth gear, a twenty-seventh gear, a twenty-eighth gear and a twenty-ninth gear, the tenth transmission shaft is provided with a thirtieth gear, a thirty-first gear, a thirty-second gear and a thirty-third gear, and the eleventh transmission shaft is provided with a thirty-fourth gear. The twenty-sixth gear meshes with the thirtieth gear, the twenty-seventh gear meshes with the thirty-first gear, the twenty-eighth gear meshes with the thirty-second gear, and the thirty-second gear meshes with the thirty-fourth gear.

[0051] The central transmission unit 6 may include: a sixth housing, a twelfth transmission shaft and left and right half-shaft transmission mechanisms. The twelfth transmission shaft is rotatably installed in the sixth housing. The two ends of the twelfth transmission shaft are respectively connected to the ninth transmission shaft of the PTO unit 5 and the PTO constant meshing unit 7. The left and right half-shaft transmission mechanisms are connected to the tenth transmission shaft of the PTO unit 5.

[0052] The PTO constant meshing unit 7 may include: a seventh housing and a thirteenth transmission shaft, the thirteenth transmission shaft is rotatably mounted on the seventh housing, one end of the twelfth transmission shaft is located in the seventh housing, a thirty-fifth gear is provided at one end of the twelfth transmission shaft, a thirty-sixth gear is provided on the thirteenth transmission shaft, and the thirty-fifth gear is meshed with the thirty-sixth gear.

[0053] The double-speed four-wheel drive unit 8 may include: an eighth housing, a wet clutch, a fourteenth transmission shaft and a fifteenth transmission shaft. The fourteenth transmission shaft and the fifteenth transmission shaft are both rotatably mounted on the eighth housing, the wet clutch is mounted on the fourteenth transmission shaft, the fourteenth transmission shaft is connected to the tenth transmission shaft of the PTO unit through gears, and the fourteenth transmission shaft and the fifteenth transmission shaft are connected through gear transmission.

[0054] There are two brake units 9 and two final transmission units 10, and the two final transmission units 10 are connected to the central transmission unit 6 through the left half shaft and the right half shaft. The two brake units 9 are installed between the two final transmission units 10 and the central transmission unit 6, respectively.

[0055] Furthermore, a planetary mechanism is installed in the power high and low unit 1, and the power high and low unit 1 is connected to a power high and low unit electronic control system for controlling an oil circuit.

[0056] The beneficial effects of adopting the above further technical solution are: the electric control system of the power high and low unit controls the oil circuit, acts on the planetary mechanism, and uses the planetary principle to achieve deceleration and speed increase, thereby satisfying the high and low gear switching. The electric control system controls the oil circuit, acts on the planetary mechanism to achieve high and low gear switching. Reduce costs and reduce space occupancy.

[0057] like Figures 1 to 13 As shown, further, the power high and low unit 1 is connected to the engine; the power high and low unit 1 is transmission connected to the power shuttle unit 2 through internal and external splines, and the power shuttle unit 2 is transmission connected to the main and auxiliary speed change unit 3 through internal and external splines.

[0058] The beneficial effect of adopting the above further technical solution is that the engine is connected to the power high and low unit, which is convenient for transmitting power to the power high and low unit. Each unit is connected by internal and external spline transmission to prevent relative rotation, achieve synchronous rotation, and improve system stability and reliability.

[0059] like Figures 1 to 13 As shown, further, a forward and reverse wet clutch is installed in the power shuttle unit 2, and the power shuttle unit 2 is connected to a power shuttle unit electronic control system for controlling the oil circuit.

[0060] The beneficial effects of adopting the above further technical solution are: the power shuttle unit is equipped with a forward and reverse wet clutch, the high-pressure oil circuit realizes engagement and disengagement, and the power shuttle unit electronic control system controls the oil circuit to realize gear switching, which improves the performance and efficiency of the tractor and makes the operating experience more comfortable. The electronic control system controls the oil circuit, and the forward and reverse clutch realizes the gear switching.

[0061] like Figures 1 to 13 As shown, further, the main and auxiliary transmission unit 3 has a 6-speed main transmission and a 2-speed auxiliary transmission function, the main transmission of the main and auxiliary transmission unit 3 is shifted by a synchronizer, and the auxiliary transmission of the main and auxiliary transmission unit 3 is shifted by a clutch sleeve.

[0062] The beneficial effects of adopting the above further technical solution are: 6-speed main transmission, synchronizer shifting, 2-speed auxiliary transmission, and clutch sleeve shifting, which makes the shifting smoother and easier to operate, less prone to tooth knocking, and longer gear service life.

[0063] like Figures 1 to 13 As shown, further, the housing of the hydraulic transfer case unit 4 is integrated with the rear axle housing, the hydraulic transfer case unit 4 is connected to a gear pump, and the gears of the hydraulic transfer case unit 4 are helical gears.

[0064] The beneficial effects of adopting the above-mentioned further technical solution are: the hydraulic transfer case unit drives the gear pump to provide power for the power shift control valve and the steering lifting system. The gears of the hydraulic transfer case unit adopt helical gear transmission, which is more efficient than the traditional straight tooth transmission, runs smoothly, and reduces the risk of abnormal noise. The housing of the hydraulic transfer case unit is integrated into the rear axle housing, which is more convenient to install. At the same time, the hydraulic transfer case unit has forced lubrication to reduce the failure risk of bearing gears at high speeds.

[0065] like Figures 1 to 13 As shown, further, the PTO unit 5 has a 3-speed forward rotation and a 1-speed reverse rotation function, the PTO unit 5 is installed in the rear central transmission, and a small bevel gear shaft is provided in the PTO unit 5.

[0066] The beneficial effects of adopting the above further technical solution are: PTO speed 3+1, three speeds 540 / 540E / 1000, another speed is PTO reverse, PTO unit 4-speed PTO, compared with the traditional 2-speed ratio, there are more speed options, and the machine matching selection is wider. The PTO unit is arranged in the rear central transmission, using the existing small bevel gear shaft, and the layout is compact. Compared with the traditional PTO arranged at the rear end of the rear axle housing, the axial length of the transmission chassis is greatly reduced, saving space and weight for the layout of the whole machine, and solving the problem that PTO operations need to match a variety of agricultural machinery. A variety of PTO speeds can be matched with different agricultural machinery and are suitable for various operation modes.

[0067] like Figures 1 to 13As shown, further, a wet clutch is installed in the double-speed four-wheel drive unit 8, and the double-speed four-wheel drive unit 8 has two-wheel drive, four-wheel drive and double-speed functions. The double-speed four-wheel drive unit 8 adopts a three-way oil circuit control of the double-speed four-wheel drive unit electronic control system; the wet clutch in the double-speed four-wheel drive unit 8 is a normally engaged wet clutch, and the wet clutch in the double-speed four-wheel drive unit 8 is installed in the gearbox housing.

[0068] The beneficial effects of adopting the above further technical solution are: the double-speed four-wheel drive unit provides power for the front drive axle, and realizes two-wheel drive, four-wheel drive and double-speed modes through a wet clutch. The double-speed four-wheel drive unit adopts a three-way oil circuit control of the double-speed four-wheel drive unit electronic control system. Compared with the traditional two-way oil circuit control, the whole machine performance is better. The traditional arrangement of the two-wheel drive function has no oil circuit control, the default clutch is disengaged, and the power cannot be transmitted to the front axle. The double-speed four-wheel drive unit defaults to clutch engagement, and the front axle is a four-wheel drive function in the flameout state, which can better realize ramp parking. The front axle is quickly braked after the flameout, which can not only reduce the turning radius of the tractor, but also the gear switching is realized by the wet clutch. The operating experience is more comfortable. The wet clutch of the double-speed four-wheel drive unit is arranged in the gearbox housing. Compared with the traditional arrangement in the rear axle housing, the length of the drive shaft connected to the front axle is reduced. The conventional arrangement of the two shafts with a support seat in the middle, the double-speed four-wheel drive unit can use a shaft directly connected to the front axle, which has higher transmission performance and efficiency and lower cost. The gear at the rear end of the input shaft of the double-speed four-wheel drive unit engages with the gear at the front end of the central transmission unit to achieve power transmission, and this power is transmitted to the front axle of the tractor through the wet clutch in the double-speed four-wheel drive unit. The electronic control system controls the three-way oil circuit, which acts on the wet clutch to achieve double-speed, four-wheel drive, and two-wheel drive. The traditional two-way oil circuit control and three-way control are better for the performance of the whole machine. Solve the problem of large turning radius of tractors.

[0069] like Figures 1 to 13 As shown, further, the brake unit 9 has a built-in brake, a brake pad is installed in the brake unit 9, the central transmission unit 6 is connected to the final transmission unit 10 through left and right half shafts, and the brake pad is connected to the left and right half shafts through a spline.

[0070] The beneficial effect of adopting the above further technical solution is that the brake of the brake unit is built-in, which avoids the risk of oil leakage compared with the traditional external brake. The central transmission unit transmits power to the final transmission unit through the left and right half shafts, thereby driving the rear wheels to operate.

[0071] The embodiment of the present invention provides a tractor power shift transmission system, which can be a tractor power shift transmission system structure, and its structure diagram is as follows: Figure 1 and Figure 2As shown. The power shift transmission system structure (tractor power shift transmission system) includes: the engine is connected to the power high and low unit 1, the power high and low unit 1 (the power high and low unit electronic control system controls the oil circuit, acts on the planetary mechanism, and uses the planetary principle to achieve deceleration and speed increase, thereby satisfying the high and low gear switching; the traditional structure power high and low is controlled by the electronic control system The wet clutch uses the increase and decrease of the gear meshing transmission ratio to achieve the high and low gear functions, the cost is high, and the axial space requirement is large), the power high and low unit 1 transmits power to the power shuttle unit 2 through the internal and external splines (the power shuttle unit 2, also known as the power reversing unit, is equipped with a forward and reverse wet clutch, and the high-pressure oil circuit realizes the engagement and separation of the wet clutch, and the power shuttle The electronic control system of the hydraulic transfer case unit controls the oil circuit to achieve gear switching, which improves the performance and efficiency of the tractor and makes the operating experience more comfortable). The power shuttle unit 2 transmits power to the main and auxiliary transmission units 3 (main transmission 6 speeds, synchronizer shifting, auxiliary transmission 2 speeds, meshing sleeve shifting) through internal and external spline connections. The hydraulic transfer case unit 4 (the hydraulic transfer case unit 4 drives the gear pump to provide power for the power shift control valve and the steering lifting system. The gears of the hydraulic transfer case unit 4 are transmitted by helical gears. Compared with the traditional straight tooth transmission ratio, it has higher efficiency, smoother operation and reduces the risk of abnormal noise. The housing of the hydraulic transfer case unit is integrated into the rear axle housing, which is more convenient to install. At the same time, the hydraulic transfer case unit 4 is equipped with forced lubrication to reduce the bearing gears at high speeds. The failure risk caused by the situation), PTO unit 5 (PTO speed 3+1, three speeds 540 / 540E / 1000, the other speed is PTO reverse, this unit has 4-speed PTO, compared with the traditional 2-speed ratio, more speed options, and a wider range of machine matching options. This unit is arranged in the rear central transmission, using the existing small bevel gear shaft, with a compact layout. Compared with the traditional PTO arranged at the rear end of the rear axle housing, the axial length of the transmission chassis is greatly reduced, saving space and weight for the layout of the whole machine) greatly meets various PTO operation modes. The power passes through the main and auxiliary speed change units 3 through the spline sleeve connection to reach the central transmission unit 6, and finally the central transmission unit 6 transmits the power to the final transmission unit through the left and right half shafts. 10, and then drive the rear wheels to work, PTO constant mesh unit 7 (PTO shaft head connected to agricultural machinery), double-speed four-wheel drive unit 8 (double-speed four-wheel drive unit 8 provides power for the front drive axle, and realizes two-wheel drive, four-wheel drive and double-speed modes through wet clutch. This unit adopts three-way oil circuit control of the double-speed four-wheel drive unit electronic control system. Compared with the traditional two-way oil circuit control, the overall performance of the machine is better. The traditional layout of the two-wheel drive function has no oil circuit control, and the clutch is disengaged by default, and the power cannot be transmitted to the front axle. This unit defaults to clutch engagement, and the front axle is a four-wheel drive function when the engine is turned off, which can better realize slope parking and rapid braking of the front axle after the engine is turned off) can not only reduce the turning radius of the tractor, but also realize gear switching through the wet clutch. The operating experience is more comfortable.The wet clutch of this unit is arranged in the gearbox housing. Compared with the traditional arrangement in the rear axle housing, the length of the drive shaft connected to the front axle is reduced. The conventional arrangement with a support seat between the two shafts can use one shaft directly connected to the front axle, which has higher transmission performance and efficiency and lower cost).

[0072] The gear at the rear end of the input shaft of the double-speed four-wheel drive unit 8 engages with the gear at the front end of the central transmission unit 6 to realize power transmission, and this power is transmitted to the front axle of the tractor through the wet clutch in the double-speed four-wheel drive unit 8.

[0073] Braking unit 9 (built-in brake, the brake of this unit is built-in, compared with the traditional external brake, it avoids the risk of oil leakage); the braking unit 9 is located between the central transmission unit 6 and the final transmission unit 10, and the brake pads are connected to the left and right half shafts through splines.

[0074] The power high and low unit structure layout (the power high and low unit electronic control system controls the oil circuit, acts on the planetary mechanism, and uses the planetary principle to achieve deceleration and speed increase, thereby satisfying the high and low gear switching; the traditional structure power high and low is controlled by the electronic control system The wet clutch uses the increase and decrease of the gear meshing transmission ratio to achieve the high and low gear functions, which is costly and requires a large axial space), PTO four-speed layout structure (4-speed PTO, compared with the traditional 2-speed ratio, has more speed options and a wider range of machine matching options. This unit is arranged in the rear central transmission, using the existing small bevel gear shaft, and has a compact layout. Compared with the traditional PTO arranged at the rear end of the rear axle housing, it greatly reduces the axial length of the transmission chassis and saves space and weight for the layout of the entire machine), the structure of the double-speed four-wheel drive unit Structure layout (provides power for the front drive axle, and realizes two-wheel drive, four-wheel drive, and double-speed modes through a wet clutch. This unit adopts three-way oil circuit control of the electronic control system. Compared with the traditional two-way oil circuit control, the overall performance of the machine is better. The traditional layout of the two-wheel drive function has no oil circuit control, the clutch is disengaged by default, and the power cannot be transmitted to the front axle. This unit defaults to clutch engagement, and the front axle is a four-wheel drive function when the engine is turned off, which can better realize ramp parking and rapid braking of the front axle after the engine is turned off. The wet clutch of this unit is arranged in the gearbox housing. Compared with the traditional arrangement in the rear axle housing, the length of the drive shaft connected to the front axle is reduced. The conventional arrangement of the two shafts with a support seat in the middle can use a shaft directly connected to the front axle, which has higher transmission performance and efficiency and lower cost). The power shift transmission system structure is more advanced, intelligent, and powerful.

[0075] In addition, the present invention also provides a tractor, comprising a tractor power shift transmission system as described in any one of the above.

[0076] The beneficial effects of adopting the technical solution of the present invention are: the PTO unit has multi-speed forward and reverse functions, more speed options, and a wider range of machine matching options. A variety of PTO speeds can be matched with different agricultural machinery and are suitable for various operation modes. The double-speed four-wheel drive unit is arranged in the gearbox housing. Compared with the traditional arrangement in the rear axle housing, the length of the drive shaft connected to the front axle is reduced. The conventional arrangement of the two shafts with a support seat in the middle can use a shaft directly connected to the front axle, which has higher transmission performance and efficiency and lower cost. It solves the problem of people's higher requirements for tractor performance and efficiency, solves the problem of PTO operation needing to match a variety of agricultural machinery and solves the problem of large turning radius of tractors.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A tractor power shift transmission system, characterized in that: include: A power high and low unit, a power shuttle unit, a main and auxiliary speed change unit, a hydraulic transfer case unit, a PTO unit, a central transmission unit, a PTO constant mesh unit, a double-speed four-wheel drive unit, a brake unit, and a final transmission unit. The power high and low unit is connected to the power shuttle unit in a transmission manner, the power shuttle unit is connected to the main and auxiliary speed change units in a transmission manner, the main and auxiliary speed change units are connected to the hydraulic transfer case unit, the PTO unit, and the central transmission unit in a transmission manner, the PTO constant mesh unit, the double-speed four-wheel drive unit, and the final transmission unit are all connected to the central transmission unit, the double-speed four-wheel drive unit is installed in the transmission case, and the brake unit is installed between the central transmission unit and the final transmission unit. Between the final drive units, the PTO unit has multi-speed forward and reverse functions; the power high and low unit is installed with a planetary mechanism, and the power high and low unit is connected to a power high and low unit electronic control system for controlling the oil circuit; the power shuttle unit is installed with a forward and reverse wet clutch, and the power shuttle unit is connected to a power shuttle unit electronic control system for controlling the oil circuit; the double-speed four-wheel drive unit is installed with a wet clutch, and the double-speed four-wheel drive unit has two-wheel drive, four-wheel drive, and double-speed functions, and the double-speed four-wheel drive unit adopts a three-way oil circuit control of the double-speed four-wheel drive unit electronic control system; the wet clutch in the double-speed four-wheel drive unit is a normally engaged wet clutch, and the wet clutch in the double-speed four-wheel drive unit is installed in the gearbox housing; The power high and low unit includes: a first housing, a first transmission shaft and a planetary mechanism, the planetary mechanism and the first transmission shaft are both rotatably mounted in the first housing, one end of the first transmission shaft is connected to the engine, the other end of the first transmission shaft is connected to the power shuttle unit, and the planetary mechanism is connected to the middle of the first transmission shaft; the power shuttle unit includes: a second housing, a second transmission shaft, a third transmission shaft, a fourth transmission shaft, a forward and reverse wet clutch, the second transmission shaft, the third transmission shaft and the fourth transmission shaft are all rotatably mounted in the second housing, the forward and reverse wet clutch is mounted on the second transmission shaft, the second transmission shaft is connected to the first transmission shaft of the power high and low unit; the third transmission shaft and the fourth transmission shaft are both connected to the main and auxiliary speed change unit; the second transmission shaft is provided with a first gear and a second gear, the third transmission shaft is provided with a third gear, and the fourth transmission shaft is provided with a fourth gear and a fifth gear; the second gear is meshed with the third gear, and the third gear is meshed with the fifth gear.

2. A tractor power shift transmission system according to claim 1, characterized in that: The power high and low unit is connected to the engine; the power high and low unit is transmission-connected to the power shuttle unit through internal and external splines, and the power shuttle unit is transmission-connected to the main and auxiliary speed change units through internal and external splines.

3. A tractor power shift transmission system according to claim 1, characterized in that: The main and auxiliary transmission units have 6-speed main transmission and 2-speed auxiliary transmission functions. The main transmission of the main and auxiliary transmission units is shifted by a synchronizer, and the auxiliary transmission of the main and auxiliary transmission units is shifted by a meshing sleeve.

4. A tractor power shift transmission system according to claim 1, characterized in that: The housing of the hydraulic transfer case unit is integrated with the rear axle housing, the hydraulic transfer case unit has a forced lubrication function, the hydraulic transfer case unit is connected to a gear pump, and the gears of the hydraulic transfer case unit are helical gears.

5. A tractor power shift transmission system according to claim 1, characterized in that: The PTO unit has a 3-speed forward rotation and a 1-speed reverse rotation function, and is installed in the rear central transmission. A small bevel gear shaft is provided in the PTO unit.

6. A tractor power shift transmission system according to claim 1, characterized in that: The brake unit has a built-in brake, a brake pad is installed in the brake unit, the central transmission unit is connected to the final transmission unit through left and right half shafts, and the brake pad is connected to the left and right half shafts through splines.

7. A tractor, characterized in that: A tractor power shift transmission system comprising any one of claims 1 to 6.

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