Four-wheel drive transmission device with central differential mechanism and vehicle

Abstract

The utility model discloses a four-wheel drive transmission device with a central differential mechanism and a vehicle, which comprise a front gear box and a rear gear box which are connected through a transmission shaft, the rear gear box comprises an input gear shaft unit used for receiving power input, and a planetary gear unit is in power transmission connection with the input gear shaft unit. One part of power is transmitted to a rear secondary driven wheel through a gear ring, and the other part of power is transmitted to a transfer case unit through a sun wheel; the transfer case unit is in power transmission connection with the transmission shaft and transmits power of the sun gear to the transmission shaft; the front gearbox comprises a front input shaft unit, and the front input shaft unit is meshed with the transmission shaft and the front differential mechanism and transmits power of the transmission shaft to the front differential mechanism. The front differential is engaged with the first front output shaft and the second front output shaft. Driving force of the front output shaft and the rear two-stage driven wheel can be unequally distributed, differential speed among the front output shaft, the rear two-stage driven wheel, the front shaft left wheel and the front shaft right wheel is achieved, and dynamic property and stability are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicles, in particular to a transmission mechanism of a vehicle, and in particular to a four-wheel drive transmission device provided with a central differential mechanism and a vehicle. Background Art

[0002] With the rapid development of the automobile industry, various types of vehicles are widely used in various industries, making production and life more convenient and enriching. Among them, all-terrain off-road vehicles have entered the public's field of vision with their excellent off-road performance and price advantage.

[0003] Currently, all-terrain vehicles on the market are fuel-powered. Existing four-wheel drive transmission designs for single-seat all-terrain vehicles typically utilize a continuously variable transmission (CVT) with a rigid axle and no differential. The vehicle's engine power is transmitted to the CVT. The centrifugal action of the sling block on the CVT's driving wheel changes the rotational diameter of the driving and driven belts at different speeds to achieve speed change. The driven wheel of the CVT outputs the shifted power to the rigid axle transfer case, which evenly distributes the power to the vehicle's front and rear axles. The front and rear axles then distribute the power evenly to the left and right wheels via the rigid axle.

[0004] The defects of the four-wheel drive transmission mechanism of traditional single-seat all-terrain vehicles are mainly reflected in the following aspects: First, due to the lack of a central differential and a front axle differential, the rotation speeds of the four wheels are completely consistent. However, when cornering, the inconsistent turning radius of the four wheels will cause the linear speeds of the four wheels to be inconsistent, resulting in wheel slippage, which in turn aggravates tire wear and reduces the turning radius of the vehicle; Second, the front and rear axle driving forces are completely consistent, and load transfer will occur when the vehicle accelerates, the vertical load on the rear axle increases, and the vertical load on the front axle decreases. When the adhesion coefficient remains unchanged, the maximum friction force that the ground can provide to the front wheels is reduced. If the driving force of the power system is large, when the front and rear axle driving forces are completely consistent, it may cause the front wheels to slip, and dangerous situations such as skidding may occur, and the rear wheels will not be able to fully utilize the friction that the ground can exert on the wheels. Utility Model Content

[0005] The technical problem to be solved by the present invention is: in order to solve the technical problem of consistent driving force of the front and rear wheels in the prior art, the present invention provides a four-wheel drive transmission device and a vehicle provided with a central differential mechanism, which can achieve unequal distribution of driving force between the front output shaft and the rear secondary driven wheels, and achieve differential speed between the front output shaft and the rear secondary driven wheels and the left and right wheels of the front axle, thereby improving power and stability.

[0006] The technical solution adopted by the utility model to solve its technical problems is: a four-wheel drive transmission device provided with a central differential mechanism, including a front gearbox and a rear gearbox connected by a transmission shaft, the rear gearbox including: an input gear shaft unit for receiving power input; a planetary gear unit, the planetary gear unit is power-transmission connected to the input gear shaft unit, and transmits part of the power to the rear secondary driven wheel through the ring gear, and transmits the other part of the power to the transfer unit through the sun gear; the transfer unit, the transfer unit is power-transmission connected to the transmission shaft, and transmits the power of the sun gear to the transmission shaft; the front gearbox includes: a front input shaft unit, the front input shaft unit is meshed with the transmission shaft and the front differential, and transmits the power of the transmission shaft to the front differential; the front differential, the front differential is meshed with the first front output shaft and the second front output shaft.

[0007] The utility model is provided with a four-wheel drive transmission device and a vehicle with a central differential mechanism, and adopts a planetary gear unit as the central differential, which can realize unequal distribution of driving force between the front and rear axles, fully utilize the maximum friction force that the ground can provide, and reduce the probability of slippage of the front axle, thereby improving the power and stability of the vehicle. In conjunction with the bevel gear open differential as the front wheel differential, the differential between the front output shaft and the rear secondary driven wheel and the left and right wheels of the front axle is realized, thereby ensuring that the performance of the vehicle steering system is fully exerted.

[0008] Furthermore, in order to realize power transmission between the front output shaft and the rear secondary driven wheel, the planetary gear unit includes a planetary carrier, planetary wheels, a sun gear and a ring gear. The planetary carrier is engaged with the input gear shaft unit to receive power. The planetary wheels are connected to the planetary carrier and are engaged with the inner ring of the ring gear and the outer ring of the sun gear. The sun gear is engaged with the transfer unit, and the ring gear is engaged with the rear secondary driven wheel.

[0009] Furthermore, in order to realize the differential function between the front output shaft and the rear secondary driven wheel, the speed relationship of the planetary gear unit is: ,in is the speed of the sun gear, is the speed of the ring gear, is the rotational speed of the planet carrier, is the gear ratio between the ring gear and the sun gear, and the torque relationship of the planetary gear unit is ,in is the torque of the sun gear, is the torque of the ring gear, The torque of the planetary carrier is adjusted by adjusting the gear ratio between the ring gear and the sun gear, and the driving force between the secondary driven gear and the first front output shaft and the second front output shaft is unequally distributed.

[0010] Furthermore, in order to change the direction of the power transmitted to the transmission shaft, the transfer case unit includes a transfer case driving wheel and a transfer case driven wheel that are vertically meshed, one end of the transfer case driving wheel has a first gear, the first gear is meshed with the inner ring of the sun gear, the other end of the transfer case driving wheel is meshed with the transfer case driven wheel through a bevel gear, and the other end of the transfer case driven wheel is connected to the transmission shaft.

[0011] Furthermore, the input gear shaft unit includes an input gear shaft and a rear driven wheel. The input gear shaft receives external power input and engages with the rear driven wheel through the second gear. The third gear of the rear driven wheel engages with the inner ring of the planet carrier.

[0012] Furthermore, in order to transmit power to the rear secondary driven wheel, the rear secondary driven wheel is engaged with the fourth gear of the ring gear.

[0013] Furthermore, in order to transmit power to the front output shaft, the front input shaft unit includes a front input shaft and a front secondary driven wheel. The front input shaft is connected to the transmission shaft. The front input shaft and the front secondary driven wheel are vertically arranged and the two are engaged through bevel gears.

[0014] Furthermore, in order to transmit power to the front differential, the front differential is connected to the front secondary driven wheels.

[0015] The technical solution adopted by the utility model to solve the technical problem is: a vehicle, comprising the above-mentioned four-wheel drive transmission device provided with a central differential mechanism.

[0016] Furthermore, the vehicle is an all-terrain vehicle or an off-road racing car.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] 1. The utility model provides a four-wheel drive transmission device and a vehicle with a central differential mechanism. A planetary gear unit is used as a central differential in the rear gearbox. Power is distributed to the rear secondary driven wheels and the front output shaft through the planetary gear unit, thereby achieving unequal distribution of driving force between the rear secondary driven wheels and the front output shaft. This fully utilizes the maximum friction provided by the ground and reduces the probability of front axle slippage, thereby improving the vehicle's power and stability. At the same time, a front differential is used in the front gearbox to achieve a differential between the left and right wheels of the front axle, ensuring that the performance of the vehicle's steering system can be fully utilized.

[0019] 2. The four-wheel drive transmission device and vehicle of the present invention are provided with a central differential mechanism, and the planetary gear unit is integrated into the rear gearbox between the two stages of reduction, which can minimize the space occupied and the weight of the transmission mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Figure 1 This is a schematic structural diagram of a four-wheel drive transmission device provided with a central differential mechanism according to the present invention;

[0022] Figure 2 This is an exploded view of the rear gearbox;

[0023] Figure 3 This is an exploded view of the front gearbox.

[0024] In the picture:

[0025] 1. Rear gearbox, 11. Input gear shaft, 111. Second gear, 12. Rear primary driven gear, 121. Third gear, 13. Planet carrier, 14. Planet gears, 15. Sun gear, 16. Ring gear, 161. Fourth gear, 17. Transfer case driving gear, 171. First gear, 18. Transfer case driven gear, 19. Rear secondary driven gear;

[0026] 2. Front gearbox, 21. Front input shaft, 22. Front secondary driven wheel, 23. First front output shaft, 24. Second front output shaft, 25. Front differential;

[0027] 3. Drive shaft. DETAILED DESCRIPTION

[0028] The present invention will now be described in further detail with reference to the accompanying drawings, which are simplified schematic diagrams that illustrate the basic structure of the present invention in a schematic manner.

[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0030] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0031] like Figure 1 As shown, a four-wheel drive transmission with a central differential mechanism includes a front gearbox 2 and a rear gearbox 1 connected by a transmission shaft 3. Power is input from the rear gearbox 1, part of which is output by the rear gearbox 1 to the rear wheels, and part of the power is input to the front gear through the transmission shaft 3 and then output to the front wheels.

[0032] Single-seat, four-wheel-drive, all-terrain vehicles, due to size and space limitations, mostly utilize a fully rigid axle connection. This lack of a differential during the entire power transmission process, along with equal torque distribution between the front and rear axles, impacts the vehicle's handling stability and dynamics. Furthermore, if the planetary gear unit is located before the final reducer, because it incorporates a transfer function, both the front gearbox 2 and the rear gearbox 1 require a two-stage gear reduction to meet the requirements for speed reduction and torque increase, resulting in a larger weight and size for the entire transmission mechanism. If the planetary gear unit is located after the final reducer, because part of the power needs to be transmitted to the front wheels, two pairs of bevel gears for redirecting the power are essential. The resulting torque after the two-stage speed reduction and torque increase is excessive, requiring larger reversing bevel gears and a thicker drive shaft to meet the strength requirements of the transmission mechanism.

[0033] Therefore, the present application integrates the planetary gear unit between the two-stage reduction gearbox 1, which can minimize the occupied space and weight of the transmission mechanism.

[0034] like Figure 2 As shown, the rear gearbox 1 includes an input gear shaft unit, a planetary gear unit and a transfer unit.

[0035] The input gear unit is used to receive power input. It includes an input gear shaft 11 and a subsequent driven pulley 12. The input gear shaft 11 receives external power input and meshes with the subsequent driven pulley 12 via a second gear 111. The third gear 121 of the subsequent driven pulley 12 meshes with the inner ring of the planetary carrier 13. External power is input to the input gear shaft 11, which transmits the power to the subsequent driven pulley 12. This power is then reduced in torque by the subsequent driven pulley 12, achieving a first-stage torque reduction. The reduced power is then input into the planetary gear unit via the planetary carrier 13.

[0036] The planetary gear unit is connected to the input gear shaft unit for power transmission, and transmits part of the power to the rear secondary driven wheel 19 through the ring gear 16, and then to the rear wheel by the rear secondary driven wheel 19. The other part of the power is transmitted to the transfer unit through the sun gear 15, and then to the front gearbox 2 by the transfer unit. That is, the differential function of the front and rear axles is realized through the planetary gear unit, and the unequal power distribution between the front and rear axles is also realized.

[0037] Specifically, the planetary gear unit includes a planet carrier 13, planetary gears 14, a sun gear 15, and a ring gear 16. The planet carrier 13 meshes with the input gear shaft unit to receive power. The planetary gears 14 are connected to the planet carrier 13 and mesh with the inner ring of the ring gear 16 and the outer ring of the sun gear 15. The sun gear 15 meshes with the transfer case unit, while the ring gear 16 meshes with the rear secondary driven gear 19.

[0038] Specifically, the power of the planetary carrier 13 is transmitted to the sun gear 15 and the ring gear 16 respectively through the planetary gears 14. The sun gear 15 transmits the power to the transfer case driving gear 17, which changes the power direction through the transfer case driven gear 18 and transmits it to the transmission shaft 3, which transmits the power to the front gearbox 2.

[0039] Preferably, the transfer case unit includes a vertically meshed transfer case driving wheel 17 and a driven transfer case wheel 18. One end of the transfer case driving wheel 17 has a first gear 171, which meshes with the inner ring of the sun gear 15. The other end of the transfer case driving wheel 17 meshes with the driven transfer case wheel 18 via a bevel gear. The other end of the driven transfer case wheel 18 is connected to the transmission shaft 3.

[0040] Specifically, the power of the ring gear 16 is transmitted to the rear secondary driven wheel 19, and then output to the rear wheels of the vehicle after a first-stage deceleration and torque increase.

[0041] Preferably, the rear secondary driven wheel 19 is engaged with the fourth gear 161 of the ring gear 16 to achieve power transmission.

[0042] Because of the degree of freedom of the planetary gear unit, that is, the motion state of the vehicle body determines the motion state of the front and rear wheels, the motion state of the front and rear wheels reaches the sun gear 15 and ring gear 16 of the planetary gear unit respectively through the transmission mechanism. The speed of the sun gear 15 and the ring gear 16 jointly determine the speed of the planet carrier 13. The speed relationship of the planetary gear unit is: ,in is the speed of the sun gear, is the speed of the ring gear, is the rotational speed of the planet carrier, is the gear ratio between the ring gear and the sun gear. The rotational speed of the sun gear and the rotational speed of the ring gear do not affect each other, thereby realizing the differential function between the front and rear axles.

[0043] The torque relationship of the planetary gear unit is ,in is the torque of the sun gear, is the torque of the ring gear, = ...

[0044] like Figure 3 As shown, the front gearbox 2 includes a front input shaft unit and a front differential 25 .

[0045] Specifically, the front input shaft unit engages with the propeller shaft 3 and the front differential 25 , and transmits the power of the propeller shaft 3 to the front differential 25 .

[0046] Preferably, the front input shaft unit includes a front input shaft 21 and two front driven wheels 22. A front differential 25 meshes with a first front output shaft 23 and a second front output shaft 24. The front differential 25 is connected to the two front driven wheels 22. The front input shaft 21 is connected to the transmission shaft 3, and the front input shaft 21 and the two front driven wheels 22 are arranged perpendicularly and meshed via bevel gears.

[0047] Specifically, power from the drive shaft 3 is input through the front input shaft 21, decelerated and torque-increased by the front secondary driven wheels 22, and then transmitted to the front differential 25. The front differential 25 transmits power to the left and right wheels via the first and second front output shafts 23 and 24, achieving differential speed between the left and right wheels on the front axle.

[0048] A vehicle includes the above-mentioned four-wheel drive transmission device with a central differential mechanism. The vehicle is a small all-terrain vehicle or an entertainment off-road racing vehicle.

[0049] The utility model is provided with a four-wheel drive transmission device and a vehicle with a central differential mechanism, which can realize unequal distribution of driving force between the front output shaft and the rear secondary driven wheels, realize differential speed between the front output shaft and the rear secondary driven wheels and the left and right wheels of the front axle, and improve power and stability.

[0050] The above description is based on the ideal embodiment of the present invention. Based on the above description, relevant personnel can make various changes and modifications without departing from the technical scope of this utility model. The technical scope of this utility model is not limited to the content of the specification and must be determined according to the scope of the claims.

Claims

1. A four-wheel drive transmission device with a central differential mechanism, comprising a front gearbox (2) and a rear gearbox (1) connected via a transmission shaft (3), characterized in that: The rear gearbox (1) comprises: An input gear shaft unit for receiving power input; A planetary gear unit, wherein the planetary gear unit is connected to the input gear shaft unit for power transmission, and transmits a portion of the power to the rear secondary driven wheel (19) through the ring gear (16), and transmits another portion of the power to the transfer case unit through the sun gear (15); A transfer case unit, the transfer case unit being connected to the transmission shaft (3) in a power transmission manner, transmitting the power of the sun gear (15) to the transmission shaft (3); The front gearbox (2) comprises: a front input shaft unit, the front input shaft unit being engaged with the drive shaft (3) and the front differential (25), and transmitting power of the drive shaft (3) to the front differential (25); A front differential (25) is engaged with the first front output shaft (23) and the second front output shaft (24).

2. The four-wheel drive transmission device with a central differential mechanism according to claim 1, characterized in that: The planetary gear unit comprises a planet carrier (13), planetary wheels (14), a sun gear (15) and a ring gear (16); the planet carrier (13) is engaged with an input gear shaft unit to receive power; the planetary wheels (14) are connected to the planet carrier (13) and are engaged with an inner ring of the ring gear (16) and an outer ring of the sun gear (15); the sun gear (15) is engaged with a transfer unit; and the ring gear (16) is engaged with a rear secondary driven wheel (19).

3. The four-wheel drive transmission device with a central differential mechanism according to claim 2, characterized in that: The speed relationship of the planetary gear unit is ,in is the speed of the sun gear, is the speed of the ring gear, is the rotational speed of the planet carrier, is the gear ratio between the ring gear and the sun gear, and the torque relationship of the planetary gear unit is ,in is the torque of the sun gear, is the torque of the ring gear, The torque of the planetary carrier is adjusted by adjusting the gear ratio between the ring gear and the sun gear, so that the driving forces of the secondary driven wheel (19), the first front output shaft (23) and the second front output shaft (24) are unequally distributed.

4. The four-wheel drive transmission device with a central differential mechanism according to claim 3, characterized in that: The transfer case unit comprises a transfer case driving wheel (17) and a transfer case driven wheel (18) that are vertically meshed, one end of the transfer case driving wheel (17) having a first gear (171), the first gear (171) meshing with the inner ring of the sun gear (15), and the other end of the transfer case driven wheel (18) being connected to the transmission shaft (3).

5. The four-wheel drive transmission device with a central differential mechanism according to claim 3, characterized in that: The input gear shaft unit comprises an input gear shaft (11) and a rear-stage driven wheel (12), wherein the input gear shaft (11) receives external power input and meshes with the rear-stage driven wheel (12) through a second gear (111), and the third gear (121) of the rear-stage driven wheel (12) meshes with the inner ring of the planet carrier (13).

6. The four-wheel drive transmission device with a central differential mechanism according to claim 3, characterized in that: The rear secondary driven wheel (19) is meshed with the fourth gear (161) of the ring gear (16).

7. The four-wheel drive transmission device with a central differential mechanism according to claim 1, characterized in that: The front input shaft unit comprises a front input shaft (21) and a front secondary driven wheel (22); the front input shaft (21) is connected to the transmission shaft (3); the front input shaft (21) and the front secondary driven wheel (22) are arranged vertically, and the two are meshed through bevel gears.

8. The four-wheel drive transmission device with a central differential mechanism according to claim 7, characterized in that: The front differential (25) is connected to the front secondary driven wheel (22).

9. A vehicle, characterized in that: A four-wheel drive transmission device with a central differential mechanism comprising the method according to any one of claims 1 to 8.

10. The vehicle according to claim 9, characterized in that The vehicle is an all-terrain vehicle or an off-road racing car.

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