Power assembly and all-terrain vehicle adopting same

Abstract

The application provides a power assembly and an all-terrain vehicle adopting the power assembly. The power assembly comprises an engine and a gear box. The gear box comprises a box body, an input shaft, a shifting mechanism, an output shaft and a gear set. The shifting mechanism comprises a shifting hub and a shift fork. The gear box further comprises a parking mechanism. The parking mechanism comprises a parking gear, a parking cam, a fixed shaft, a first transmission member and a second transmission member. The first transmission member surrounds the parking cam and has an abutting portion extending towards the parking cam. When the parking cam rotates to a predetermined position, the parking cam can abut against the abutting portion and drive the first transmission member to rotate around the fixed shaft. The second transmission member has an engaging portion formed at an end away from the fixed shaft. The second transmission member can drive the engaging portion to engage with the parking gear by rotating, or the second transmission member can drive the engaging portion to disengage from the parking gear by rotating the first transmission member. Through the above arrangement, the occupied space of the power assembly is reduced, and the service life of the shifting hub is improved.

Description

Technical Field

[0001] This application relates to the field of vehicle engineering, and in particular to a powertrain and an all-terrain vehicle using the powertrain. Background Technology

[0002] A powertrain is a collection of components that provide and transmit power for vehicle movement. The engine and transmission are connected in the powertrain. The engine includes a magneto. The crankshaft of the engine is coaxially mounted with gears for connecting the engine's balance shaft, gears or sprockets for driving the water pump, and gears or sprockets for driving the oil pump. All of these components are located on the side of the engine away from the transmission.

[0003] In related technologies, the transmission device includes a continuously variable transmission (CVT) and a gearbox. The CVT is connected between the gearbox and the engine. The gearbox is used to change the transmission ratio between the drive shaft and the crankshaft, wherein the drive shaft is connected to the wheels. The gearbox housing forms a receiving cavity, and a parking mechanism is installed within the receiving cavity. The parking mechanism can lock the output shaft of the gearbox to achieve vehicle parking.

[0004] While the aforementioned powertrain can achieve the vehicle parking function, on the one hand, the housing also houses components such as the transmission gear set, and the parking mechanism itself is relatively large, resulting in a large space occupied by the housing and the corresponding space occupied by the housing itself. On the other hand, the transmission components, parking cam, and transmission hub of the parking mechanism are coaxially arranged, and the torque generated during parking is mainly borne by the transmission hub, leading to a shorter service life for the transmission hub. Utility Model Content

[0005] The purpose of this application is to provide a powertrain and an all-terrain vehicle using the powertrain, which has a smaller overall size and a longer service life for its transmission hub.

[0006] To achieve the above objectives, this application adopts the following technical solution:

[0007] In a first aspect, this application provides a powertrain comprising an engine and a gearbox. The gearbox includes a housing, an input shaft, a shift mechanism, an output shaft, and a transmission gear set. The gearbox is connected to the engine via the input shaft. The shift mechanism includes a transmission hub and a shift fork connected to the transmission hub. The input shaft, output shaft, and transmission hub are all supported by the housing. The transmission gear set is connected between the input shaft and the output shaft. The end of the shift fork away from the transmission hub acts on the transmission gear set and can change the transmission ratio of the transmission gear set. The gearbox also includes a parking mechanism, which includes a parking gear, a parking cam, a fixed shaft, a first transmission component, and a second transmission component. The parking gear is mounted on the output shaft and fixed to the output shaft. The parking cam is coaxially connected to the transmission hub. A fixed shaft is fixed to the housing and located between the parking gear and the parking cam. The axis of the fixed shaft is parallel to the axis of the output shaft. A first transmission member is mounted on the fixed shaft and surrounds the parking cam. The first transmission member has an abutment portion extending towards the parking cam. When the parking cam rotates to a predetermined position, the parking cam can abut against the abutment portion and drive the first transmission member to rotate around the fixed shaft. A second transmission member is mounted on the fixed shaft and connected to the first transmission member. The end of the second transmission member away from the fixed shaft forms a meshing portion. The second transmission member can engage the meshing portion with the parking gear by rotating, or the second transmission member can disengage the meshing portion by rotating the first transmission member.

[0008] Furthermore, the distance between the rotation center line of the transmission hub and the axis of the fixed shaft is defined as the first distance, and the distance between the rotation center line of the transmission hub and the axis of the output shaft is defined as the second distance. The ratio of the first distance to the second distance ranges from 0.47 to 0.72.

[0009] Furthermore, observing along the extension direction of the fixed shaft axis, the line connecting the output shaft axis to the fixed shaft axis is defined as the first extension line, and the line connecting the fixed shaft axis to the rotation center line of the transmission hub is defined as the second extension line. The angle between the first extension line and the second extension line ranges from 25° to 40°.

[0010] Furthermore, the parking mechanism also includes an elastic element, one end of which abuts against the first transmission element and the other end of which abuts against the second transmission element. When the meshing part abuts against the teeth of the parking gear, if the parking gear rotates, the meshing part can be engaged in the tooth groove between two adjacent teeth under the action of the elastic element.

[0011] Furthermore, the elastic element is a torsion spring, which forms an annular mounting portion. The mounting portion is fitted onto the second transmission element, and the center line of the mounting portion coincides with the axis of the fixed shaft.

[0012] Furthermore, the first transmission member includes an unlocking part extending toward the engagement part. When the parking cam rotates in the first direction, the second transmission member rotates around a fixed shaft under the action of the elastic member. When the parking cam rotates in the second direction, the unlocking part abuts against the engagement part and applies a force away from the parking gear to the engagement part. The first direction is opposite to the second direction.

[0013] Furthermore, the first transmission member forms an annular structure, with the abutment portion located on the inner edge of the annular structure. The parking cam is located within the space formed by the annular structure, and the outer edge of the parking cam is provided with a protruding structure. When the parking cam rotates in the first direction, the protruding structure can abut against the abutment portion and drive the first transmission member to rotate, so that the meshing portion engages with the parking gear. When the parking cam rotates in the second direction, the protruding structure can abut against the inner edge of the annular structure and drive the first transmission member to rotate, so that the meshing portion separates from the parking gear.

[0014] Furthermore, the housing forms a storage cavity for the gear shifting mechanism and the output shaft. The parking mechanism is installed outside the storage cavity. The parking mechanism also includes a parking linkage and a drive gear. At least a portion of the parking linkage passes through the housing and extends outside the housing. The drive gear is connected to the parking linkage and is located outside the housing. The drive gear is connected to the parking cam drive.

[0015] Furthermore, in the vertical direction of the powertrain, the rotation center line of the transmission hub has a first height difference with the axis of the input shaft, and the rotation center line of the transmission hub has a second height difference with the axis of the output shaft. The ratio of the first height difference to the second height difference ranges from 0.9 to 1.42.

[0016] Secondly, this application also provides an all-terrain vehicle, which includes a frame, a running gear and a suspension system, wherein the running gear is at least partially located below the frame, the suspension system connects the running gear to the frame, and the all-terrain vehicle also includes any of the aforementioned powertrains, the powertrain being supported by the frame and used to drive the running gear.

[0017] The aforementioned powertrain incorporates a fixed shaft, fixed to the housing and located between the parking gear and the parking cam. A first transmission component and a second transmission component are mounted on this fixed shaft. The rotation of the first and second transmission components engages the parking gear at their meshing portion, thereby parking the vehicle. Because the fixed shaft is not coaxial with the transmission hub, it can bear at least a portion of the torque during rotation, reducing the torque borne by the transmission hub and thus extending its service life. Furthermore, the first and second transmission components overlap at least partially during rotation, reducing their vertical space requirements and consequently minimizing the overall vertical space occupied by the powertrain. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the powertrain in the embodiments of this application;

[0019] Figure 2 This is an exploded view of the powertrain in the embodiment of this application;

[0020] Figure 3 This is a schematic diagram of the crankshaft and balance shaft in the embodiments of this application;

[0021] Figure 4 This is a first schematic diagram of the internal structure of the powertrain in the embodiments of this application;

[0022] Figure 5 This is a schematic diagram of the accessory gear train in the embodiments of this application;

[0023] Figure 6 This is a schematic diagram of a continuously variable transmission (CVT) according to an embodiment of this application;

[0024] Figure 7 This is a second schematic diagram of the internal structure of the powertrain in the embodiments of this application;

[0025] Figure 8 This is a schematic diagram of the transmission method of the water pump and oil pump in the embodiments of this application;

[0026] Figure 9 This is a schematic diagram of the parking mechanism and the transmission gear set in the embodiments of this application;

[0027] Figure 10 This is a first schematic diagram of the parking mechanism in the embodiments of this application;

[0028] Figure 11 This is a second schematic diagram of the parking mechanism in the embodiments of this application;

[0029] Figure 12 This is a schematic diagram of the transmission hub, input shaft, and output shaft in the embodiments of this application;

[0030] Figure 13 This is a schematic diagram of an all-terrain vehicle according to an embodiment of this application. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0032] It should be noted that the terms "first," "second," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms "a" or "one," etc., do not indicate a quantity limitation, but rather indicate the presence of at least one. "A plurality of," or "several," indicates at least two. Unless otherwise stated, terms such as "front and back," "left and right," "up and down," etc., are for illustrative purposes only and are not limited to a single location or spatial orientation. The terms "connected" or "linked," etc., are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0033] like Figure 1 As shown, this application provides a powertrain 100, which includes an engine 11 and a transmission 12. The engine 11 is a device that converts chemical energy into mechanical energy by reciprocating one or more pistons (not shown) through the pressure generated by igniting the fuel-air mixture, and outputs the generated kinetic energy to drive the transmission 12 or wheels connected thereto. The transmission 12 can change the speed and torque of the engine 11, and change the transmission ratio between the engine 11 and the wheels to adapt to driving conditions, realize reverse driving, and interrupt power transmission.

[0034] Engine 11 includes a housing 111, which includes a cylinder block 1111, a crankcase 1112, and an oil pan 1113 connected in sequence. The oil pan 1113 is located at the bottom of the housing 111 and forms an oil pan space 1113a for storing lubricating oil (see [link to relevant documentation]). Figure 4 The crankcase 1112 is connected to the oil pan 1113, and the crankcase 1112 forms the crankcase space 1112a (see...). Figure 4 The cylinder body 1111 forms a cylinder 1111a that houses the piston and provides reciprocating motion for the piston (see...). Figure 4 Cylinder 1111a is connected to crankcase space 1112a.

[0035] To clearly illustrate the technical solution of this application, the following are also defined: Figure 1 The diagram shows the front-to-back, left-to-right, and up-down directions of the powertrain 100. It should be noted that the front-to-back, left-to-right, and up-down directions in this document refer to the directions in which the powertrain 100 is installed in the vehicle.

[0036] like Figure 2As shown, the engine 11 also includes a crankshaft connecting rod mechanism 112, a magneto 113, a lubrication system 114, and a balancing mechanism 115. The crankshaft connecting rod mechanism 112 is mounted in the crankcase 1112 and located within the crankcase space 1112a. The crankshaft connecting rod mechanism 112 includes a crankshaft 1121 and a connecting rod (not shown) connected to the crankshaft 1121. The rotation center line of the crankshaft 1121 is parallel to the left-right direction of the powertrain 100. The connecting rod is fitted onto the journal of the crankshaft 1121, and the end of the connecting rod facing away from the crankshaft 1121 is connected to the piston. When the piston moves within the cylinder 1111a under pressure, the connecting rod can drive the crankshaft 1121 to rotate relative to the crankcase 1112.

[0037] The magneto 113 is coaxially connected to the crankshaft 1121 and is located at one end of the crankshaft 1121. In the technical solution of this application, the other end of the crankshaft 1121 is connected to the transmission device 12.

[0038] The lubrication system 114 includes an oil pump 1141, which delivers lubricating oil from the oil pan 1113 to the corresponding lubrication areas. Lubrication areas may be the connection between the piston and connecting rod, the connection between the connecting rod and crankshaft 1121, or the connection between the crankshaft 1121 and crankcase 1112. These are merely examples of lubrication areas; any area in the engine 11 that requires lubrication to reduce wear between hardware components can have lubricating oil delivered to it by pumping it through the oil pump 1141.

[0039] The balancing mechanism 115 includes a balance shaft 1151, which is connected to the crankshaft 1121, and the rotation center line of the balance shaft 1151 is parallel to the rotation center line of the crankshaft 1121. The balance shaft 1151, through its eccentric structure that rotates in the opposite direction to the crankshaft 1121, counteracts the inertial force generated by the high-speed movement of the piston in the engine 11, thereby reducing vibration.

[0040] like Figure 3 As shown, in one implementation, the crankshaft 1121 is connected to a transmission gear 1121a at the end opposite to the magneto 113, and the crankshaft 1121 drives the balance shaft 1151 through the transmission gear 1121a. The balance shaft 1151 is connected to a drive sprocket 1151a at the end opposite to the transmission gear 1121a, and the drive sprocket 1151a can rotate synchronously with the balance shaft 1151. The drive sprocket 1151a is connected to the oil pump 1141 through a chain 1141a, so that the oil pump 1141 can work under the drive of the balance shaft 1151.

[0041] With the above configuration, the balance shaft 1151 drives the oil pump 1141, and the balance shaft 1151 serves as the medium for power transmission between the crankshaft 1121 and the oil pump 1141. This eliminates the need for a drive sprocket 1151a at the crankshaft 1121 to drive the oil pump 1141, thereby shortening the length of the crankshaft 1121. Correspondingly, the width of the crankcase 1112 can also be designed to be shorter in the left-right direction of the powertrain 100, reducing the space occupied by the powertrain 100 in the left-right direction.

[0042] Furthermore, using the balance shaft 1151 as the medium for power transmission between the crankshaft 1121 and the oil pump 1141 can also improve the flexibility of the oil pump 1141's arrangement. By changing the position of the drive sprocket 1151a on the balance shaft 1151, the arrangement of the oil pump 1141 can be adaptively adjusted.

[0043] like Figure 3 As shown in this embodiment, two balance shafts 1151 are used. Each balance shaft 1151 is connected to the crankshaft 1121 via a transmission gear 1121a, and the rotation center lines of both balance shafts 1151 are parallel to the rotation center line of the crankshaft 1121. To clearly illustrate the technical solution of this application, the two balance shafts 1151 are defined as a first balance shaft 1151b and a second balance shaft 1151c. The first balance shaft 1151b and the second balance shaft 1151c are respectively disposed on the front and rear sides of the crankshaft 1121, and the drive sprocket 1151a is connected to the end of the first balance shaft 1151b that is away from the transmission gear 1121a. By using two balance shafts 1151, the inertial force generated when the crankshaft 1121 rotates can be better balanced, reducing the vibration and noise of the engine 11.

[0044] Specifically, both the first balance shaft 1151b and the second balance shaft 1151c are connected to driven gears. To clearly illustrate the technical solution of this application, the driven gear connected to the first balance shaft 1151b is defined as the first driven gear 1151d. The first driven gear 1151d is fitted onto the end of the first balance shaft 1151b facing away from the magneto 113 and is splinedly connected to the first balance shaft 1151b, enabling the first driven gear 1151d to rotate synchronously with the first balance shaft 1151b. The driven gear connected to the second balance shaft 1151c is defined as the second driven gear 1151e. The second driven gear 1151e is fitted onto the end of the second balance shaft 1151c facing away from the magneto 113 and is splinedly connected to the second balance shaft 1151c, enabling the second driven gear 1151e to rotate synchronously with the second balance shaft 1151c. The transmission gear 1121a meshes with both the first driven gear 1151d and the second driven gear 1151e simultaneously.

[0045] It should be noted that, since the crankshaft 1121 transmits power to the first balance shaft 1151b and the second balance shaft 1151c through gears, the rotation directions of the first balance shaft 1151b and the second balance shaft 1151c are opposite to the rotation direction of the crankshaft 1121, thereby reducing the inertial force generated by the uneven mass distribution of the crankshaft 1121 when it rotates.

[0046] like Figure 4 As shown, viewed along the left-right direction of the powertrain 100, the line connecting the rotation center of the first balance shaft 1151b and the rotation center of the crankshaft 1121 is defined as the first straight line 102, and the line connecting the rotation center of the second balance shaft 1151c and the rotation center of the crankshaft 1121 is defined as the second straight line 103. The rotation center of the first balance shaft 1151b coincides with its axis, and the rotation center of the second balance shaft 1151c coincides with its axis.

[0047] The first straight line 102 forms a first angle θ with the cylinder center line 101 of the cylinder block 1111, and the second straight line 103 forms a second angle γ with the cylinder center line 101 of the cylinder block 1111. The second angle γ is the same as the first angle θ. The cylinder 1111a is basically cylindrical.

[0048] Since the first included angle θ and the second included angle γ are the same, the following only limits the angle range of the first included angle θ. As one implementation, the range of the first included angle θ is 65° to 90°; further, the range of the first included angle θ is 68° to 85°. More preferably, the range of the first included angle θ is 71° to 81°.

[0049] It should be noted that having the same first angle θ and the same second angle γ allows the first balance shaft 1151b and the second balance shaft 1151c to better reduce the inertial force generated by the rotation of the crankshaft 1121. If the range of the first angle θ is too large, the first balance shaft 1151b and the second balance shaft 1151c will encroach on the positions of other components (such as the oil pump 1141, water pump 116, etc.) in the longitudinal direction of the powertrain 100, resulting in a larger space volume occupied by the powertrain 100 in the longitudinal direction. If the range of the first angle θ is too small, the first balance shaft 1151b and the second balance shaft 1151c will be too close to the cylinder 1111a, and the chain 1141a connecting the first balance shaft 1151b and the oil pump 1141 may interfere with the crankshaft 1121. It is necessary to set a corresponding chain baffle to change the extension direction of the chain 1141a, which will increase the number of parts in the engine 11 and affect the spatial layout of the engine 11. The above arrangement makes the layout of the components in the engine 11 more compact and improves the space utilization efficiency, thereby reducing the space occupied by the powertrain 100 in the front-rear direction.

[0050] like Figure 4 As shown, in one implementation, the cylinder centerline 101 of the cylinder block 1111 extends rearward and upward towards the powertrain 100, the first balance shaft 1151b is located frontward and above the crankshaft 1121, and the oil pump 1141 is located frontward and below the crankshaft 1121. This minimizes the space occupied by the first balance shaft 1151b and the oil pump 1141 in the longitudinal direction of the powertrain 100. Since the connection point between the crankcase 1112 and the cylinder block 1111 is always higher than the first balance shaft 1151b, even if the first balance shaft 1151b is positioned frontward and above the crankshaft 1121, it will not increase the vertical space occupied by the crankcase 1112. Through the above arrangement, the vertical space occupied by the powertrain 100 can be reduced without changing the vertical space occupied by the powertrain 100.

[0051] The oil pump 1141 has an oil pump sprocket 1141b connected to a chain 1141a. Viewed from the left-right direction of the powertrain 100, a reference line 104 is defined as the line connecting the rotation center of the oil pump sprocket 1141b and the rotation center of the drive sprocket 1151a. The rotation center of the oil pump sprocket 1141b coincides with its axis, and the rotation center of the drive sprocket 1151a coincides with its axis.

[0052] like Figure 4 As shown, in one implementation, the reference line 104 extends rearward and upward toward the engine 11, and the angle α between the reference line 104 and the horizontal plane 105 ranges from 75° to 85°. Further, the angle α between the reference line 104 and the horizontal plane 105 ranges from 78° to 83°. More preferably, the angle α between the reference line 104 and the horizontal plane 105 ranges from 81° to 82°.

[0053] It should be noted that the oil pump 1141 is located close to the oil pan 1113, meaning at least a portion of the oil pump 1141 is located below the crankcase space 1112a. If the included angle α is too small, with the first balance shaft 1151b fixed in position, the oil pump 1141's position will shift forward of the powertrain 100, increasing the distance between the crankshaft 1121 and the oil pump 1141 in the longitudinal direction of the powertrain 100, and increasing the space occupied by the crankcase 1112 in the longitudinal direction. If the included angle α is too large, the chain 1141a may interfere with the crankshaft 1121, requiring a corresponding chain 1141a baffle to change the extension direction of the chain 1141a, which would increase the number of components inside the engine 11 and affect the spatial layout of the engine 11. Through the above arrangement, the space occupied by the crankcase 1112 in the longitudinal direction of the powertrain 100 is reduced while ensuring that the oil pump 1141 does not encroach on other components.

[0054] like Figure 5 As shown, in one implementation, the transmission device 12 includes a gearbox 122, which includes an input shaft 1221, an output shaft 1223, and a transmission gear set 1224. The gearbox 122 is connected to the engine 11 via the input shaft 1221. The power generated by the engine 11 is transmitted from the input shaft 1221 to the output shaft 1223. The transmission gear set 1224 is connected between the input shaft 1221 and the output shaft 1223 and is used to change the transmission ratio between the input shaft 1221 and the output shaft 1223.

[0055] In the implementation of this application, the gearbox 122 housing is integrally formed with the crankcase 1112, and the internal space of the gearbox 122 housing is connected to the crankcase space 1112a.

[0056] Specifically, the gearbox 122 also includes an accessory gear train 1226 disposed within its housing and a drive shaft 1227 connected to the accessory gear train 1226. The drive shaft 1227 extends along the longitudinal direction of the powertrain 100 and passes through the crankcase 1112, and is capable of transmitting power to the wheels. The accessory gear train 1226 connects the output shaft 1223 and the drive shaft 1227 to transmit power from the output shaft 1223 to the drive shaft 1227. The accessory gear train 1226 is also capable of changing the rotational speed and power direction from the output shaft 1223 to the drive shaft 1227.

[0057] The accessory gear train 1226 includes at least one gear. When there are multiple gears in the accessory gear train 1226, the multiple gears have different sizes, number of teeth, and types. For example, the gear types include spiral bevel gears, disc gears, and / or double gears, etc. The conversion of the power transmission direction is achieved by the interaction of the above different types of gears.

[0058] like Figure 6 As shown, the transmission 12 also includes a continuously variable transmission (CVT) 121, which includes a drive pulley set 1211 and a driven pulley set 1212. The drive pulley set 1211 and the driven pulley set 1212 are connected by a drive belt. The drive pulley set 1211 is connected to the crankshaft 1121, and the driven pulley set 1212 is connected to the accessory gear train 1226. Along the left-right direction of the powertrain 100, the oil pump 1141 is located on the side of the drive shaft 1227 opposite to the CVT 121.

[0059] With the above configuration, the first balance shaft 1151b serves as the power transmission medium between the crankshaft 1121 and the oil pump 1141, and the drive sprocket 1151a determines the arrangement of the oil pump 1141. This positions the oil pump 1141 on the side of the drive shaft 1227 away from the continuously variable transmission (CVT) 121, allowing the drive shaft 1227 to be as close to the CVT 121 as possible. This provides more space on the side of the drive shaft 1227 away from the CVT 121, facilitating the arrangement of the oil pump 1141 and the accessory gear train 1226, and improving the space utilization efficiency within the engine 11.

[0060] like Figure 4 As shown, in one implementation, the engine 11 also includes a starting system 117, which includes a starter motor 1171 and a reduction gear set 1172. The starter motor 1171 is connected to the reduction gear set 1172, and the starter motor 1171 is connected to the magneto 113 through the reduction gear set 1172.

[0061] The crankcase 1112 includes a first housing 1112b and a second housing 1112c, with the first housing 1112b located in front of the second housing 1112c. In this embodiment, the first housing 1112b and the second housing 1112c are integrally formed, and their internal spaces are connected. The first housing 1112b houses the accessory gear train 1226, and the second housing 1112c is detachably connected to the side cover 1114 and houses the reduction gear set 1172, the first balance shaft 1151b, and the oil pump 1141.

[0062] In the left-right direction of the powertrain 100, the width of the first housing 1112b is defined as the first width W1, and the total width of the second housing 1112c and the side cover 1114 is defined as the second width W2, where the first width W1 is less than the second width W2. As one implementation, the ratio of the first width W1 to the second width W2 ranges from 0.4 to 0.64. Further, the ratio ranges from 0.45 to 0.58. More preferably, the ratio ranges from 0.49 to 0.51. This creates a clearance space in front of the side cover 1114, which can be used as a space for arranging related vehicle accessories, such as the chassis and body panels. Since the first housing 1112b is used to house the accessory wheel system 1226, and the width of the first housing 1112b remains constant when the structure of the accessory wheel system 1226 is fixed, if the ratio is too small, although it can increase the width of the space in front of the side cover 1114 in the left and right directions, it will lead to redundant space inside the engine 11, which is not conducive to the miniaturization design of the engine 11. Through the above settings, the overall layout of the powertrain 100 is optimized, and the space occupied by the powertrain 100 is reduced while ensuring the versatility of the powertrain 100.

[0063] like Figure 7and Figure 8 As shown, in one implementation, the engine 11 also includes a water pump 116, which is located behind the crankshaft 1121 and is connected to the second balance shaft 1151c via a drive.

[0064] When the crankshaft 1121 rotates, power is transmitted from the crankshaft 1121 to the first driven gear 1151d through the transmission gear 1121a, thereby driving the first balance shaft 1151b to rotate. When the first balance shaft 1151b rotates under the drive of the crankshaft 1121, power is transmitted from the first balance shaft 1151b to the chain 1141a through the drive sprocket 1151a, and then to the oil pump 1141 through the chain 1141a, thereby driving the oil pump 1141 to work.

[0065] Power is also transmitted from the crankshaft 1121 to the second driven gear 1151e via the transmission gear 1121a, thereby driving the second balance shaft 1151c to rotate. When the second balance shaft 1151c rotates under the drive of the crankshaft 1121, power is transmitted from the second balance shaft 1151c to the water pump 116, thereby driving the water pump 116 to work.

[0066] With the above configuration, the first balance shaft 1151b and the second balance shaft 1151c drive the oil pump 1141 and the water pump 116 respectively, making the arrangement of the components inside the engine 11 more reasonable and improving the utilization efficiency of the space inside the engine 11. Compared with related technologies, the number of parts on the crankshaft 1121 is reduced. That is, there is no need to set up structures on the crankshaft 1121 to drive the oil pump 1141 and the water pump 116. Only a transmission gear 1121a is needed to drive the oil pump 1141 and the water pump 116 simultaneously through the first balance shaft 1151b and the second balance shaft 1151c, thereby shortening the length of the crankshaft 1121 and further reducing the space occupied by the powertrain 100 in the left and right directions.

[0067] As one implementation method, the oil pump 1141 and the water pump 116 are driven by the first balance shaft 1151b and the second balance shaft 1151c respectively, so as to design the transmission ratio between the oil pump 1141 and the first balance shaft 1151b, and between the water pump 116 and the second balance shaft 1151c, so as to realize that the oil pump 1141 and the water pump 116 operate at different speeds.

[0068] With the above arrangement, on the one hand, the oil pump 1141 and the water pump 116 are respectively connected to different balance shafts 1151. The oil pump 1141 and the first balance shaft 1151b are located on the front side of the crankshaft 1121, while the water pump 116 and the second balance shaft 1151c are located on the rear side of the crankshaft 1121. This avoids the oil pump 1141, the water pump 116, and the pair of balance shafts 1151 being concentrated on one side of the crankshaft 1121, which would encroach on the position of other components. On the other hand, it facilitates the flexible adjustment of the transmission ratio between the crankshaft 1121 and the oil pump 1141, as well as the transmission ratio between the crankshaft 1121 and the water pump 116, according to the cooling and lubrication requirements of the engine 11.

[0069] like Figure 8 As shown, in one implementation, the end of the second balance shaft 1151c opposite to the second driven gear 1151e is connected to a transition gear 1151f, and the second balance shaft 1151c is driven by the water pump 116 through the transition gear 1151f. By increasing or decreasing the number of teeth on the transition gear 1151f, the transmission ratio between the water pump 116 and the second balance shaft 1151c is adjusted, so that the speed of the water pump 116 is different from the speed of the oil pump 1141.

[0070] In one implementation, the water pump 116 is located behind the crankshaft 1121. Viewed from the left-right direction along the powertrain 100, the second balance shaft 1151c is located between the water pump 116 and the crankshaft 1121. Since the second balance shaft 1151c is driven by the crankshaft 1121 and the water pump 116 is driven by the second balance shaft 1151c, the above arrangement allows for a more compact arrangement of the crankshaft 1121, the second balance shaft 1151c, and the water pump 116, reducing the space occupied by these three components in the vertical direction of the powertrain 10.

[0071] like Figure 9 As shown, gearbox 122 is connected to engine 11 via a transmission, or gearbox 122 is connected to engine 11 via continuously variable transmission 121 to change the transmission ratio between transmission shaft 1227 and crankshaft 1121. Gearbox 122 also includes a shift mechanism 1222, which includes a shift hub 1222a and a shift fork 1222b connected to the shift hub 1222a. Input shaft 1221, output shaft 1223, and shift hub 1222a are all supported by a housing. A transmission gear set 1224 is connected between input shaft 1221 and output shaft 1223. The end of shift fork 1222b facing away from shift hub 1222a acts on transmission gear set 1224 and can change the transmission ratio of transmission gear set 1224.

[0072] It should be noted that the gearbox 122 housing and the first housing 1112b mentioned above are actually the same component. For the convenience of describing the gearbox 122 and its related components, they are collectively referred to as the housing below.

[0073] Specifically, the gear set 1224 includes several gears 1224a, each with a different number of teeth. A shift fork 1222b acts on the gears 1224a with different numbers of teeth to change the transmission ratio of the gear set 1224. The structure of the gear set 1224 in this embodiment is basically the same as that of the gear set 1224 in related technologies. It is used to adjust the transmission ratio between the output shaft 1223 and the input shaft 1221. The number of gears in the gear set 1224 can be adaptively adjusted according to the number of gears in the gearbox 122.

[0074] like Figure 10 and Figure 11 As shown, in one implementation, the gearbox 122 further includes a parking mechanism 1225. The parking mechanism 1225 includes a parking gear 1225a, a parking cam 1225b, a fixed shaft 1225c, a first transmission member 1225d, and a second transmission member 1225e. The parking gear 1225a is fitted onto the output shaft 1223 and is fixedly connected to the output shaft 1223. The parking cam 1225b is coaxially connected to the transmission hub 1222a. The fixed shaft 1225c is fixed to the housing and located between the parking gear 1225a and the parking cam 1225b. The axis of the fixed shaft 1225c is parallel to the axis of the output shaft 1223. The first transmission member 1225d is mounted on the fixed shaft 1225c. A portion of the first transmission member 1225d surrounds the outer periphery of the parking cam 1225b and has an abutment portion 1225f extending toward the parking cam 1225b. When the parking cam 1225b rotates to the predetermined position, it abuts against the abutment portion 1225f and drives the first transmission member 1225d to rotate around the fixed shaft 1225c. The second transmission member 1225e is mounted on the fixed shaft 1225c and connected to the first transmission member 1225d. The end of the second transmission member 1225e facing away from the fixed shaft 1225c forms a meshing portion 1225g. The second transmission member 1225e can engage the meshing portion 1225g with the parking gear 1225a by rotating, or the second transmission member 1225e can disengage the meshing portion 1225g by rotating the first transmission member 1225d.

[0075] Specifically, the axis of the fixed shaft 1225c is parallel to the left-right direction of the powertrain 100. The first transmission member 1225d can apply a force to the second transmission member 1225e to drive the second transmission member 1225e to rotate around the fixed shaft 1225c, so that the meshing part 1225g approaches the parking gear 1225a. The outer edge of the meshing part 1225g has a toothed structure 1225h for engaging the parking gear 1225a. When the meshing part 1225g engages with the parking gear 1225a, the output shaft 1223 stops rotating with the parking gear 1225a, blocking the power transmission path and realizing the parking of the vehicle.

[0076] With the above configuration, the rotation centers of the first transmission member 1225d and the second transmission member 1225e coincide with the axis of the fixed shaft 1225c. When viewed along the extension direction of the axis of the fixed shaft 1225c, at least a portion of the first transmission member 1225d and at least a portion of the second transmission member 1225e overlap. As the meshing part 1225g meshes with the parking gear 1225a, the space occupied by the first transmission member 1225d and the second transmission member 1225e in the vertical direction of the powertrain 100 is reduced, thereby reducing the space occupied by the powertrain 100 in its own vertical direction. When the meshing part 1225g meshes with the parking gear 1225a, the second transmission member 1225e applies torque to the parking gear 1225a. The fixed shaft 1225c bears at least part of the torque, thereby reducing the torque on the transmission hub 1222a. This reduces the impact on the transmission hub 1222a when the parking gear 1225a is locked, and improves the service life of the transmission hub 1222a.

[0077] like Figure 11 As shown, in one implementation, the distance between the rotation center line of the transmission hub 1222a and the axis of the fixed shaft 1225c is defined as the first distance D1, and the distance between the rotation center line of the transmission hub 1222a and the axis of the output shaft 1223 is defined as the second distance D2. The ratio of the first distance D1 to the second distance D2 ranges from 0.47 to 0.72. Further, the ratio ranges from 0.52 to 0.65. More preferably, the ratio ranges from 0.57 to 0.58.

[0078] It should be noted that, since both the first transmission component 1225d and the second transmission component 1225e rotate during the locking of the parking gear 1225a, given the fixed positions of the transmission hub 1222a and the output shaft 1223, if the ratio is too large, the first transmission component 1225d will occupy a large amount of space in the vertical direction of the powertrain 100, which is not conducive to the arrangement of the parking mechanism 1225 within the gearbox. If the ratio is too small, the lever ratio between the first transmission component 1225d and the second transmission component 1225e will be too large, requiring a greater force to rotate the second transmission component 1225e during parking. This design makes the internal structure of the gearbox 122 more compact, reduces the overall space occupied by the powertrain 100, and makes parking easier for the user.

[0079] As one implementation, viewed along the axial extension direction of the fixed shaft 1225c, the line connecting the axis of the output shaft 1223 to the axis of the fixed shaft 1225c is defined as the first extension line 106, and the line connecting the axis of the fixed shaft 1225c to the rotation center line of the transmission hub 1222a is defined as the second extension line 107. The included angle Φ between the first extension line 106 and the second extension line 107 ranges from 25° to 40°. Further, the included angle ranges from 27° to 36°. More preferably, the included angle ranges from 30° to 32°.

[0080] It should be noted that if the included angle Φ between the first extension line 106 and the second extension line 107 is too large, the rotation angle of the first transmission component 1225d and the second transmission component 1225e will be large. Since the first transmission component 1225d is mounted on the fixed shaft 1225c, and the parking cam 1225b is coaxially connected to the transmission hub 1222a, the first transmission component 1225d surrounds the parking cam 1225b. Consequently, the required dimensions of the first transmission component 1225d and the second transmission component 1225e are large, resulting in a larger overall space occupied by the powertrain 100. A large rotation angle between the first transmission component 1225d and the second transmission component 1225e will result in excessive parking torque, reducing parking efficiency. If the ratio is too small, the rotation space between the first transmission component 1225d and the second transmission component 1225e will be limited, causing them to interact and hindering the engagement of the meshing part 1225g with the transmission gear 1121a. Furthermore, during the disengagement of the meshing part 1225g from the parking gear 1225a, the limited space results in incomplete disengagement. Through the above design, the overall space occupied by the powertrain 100 is reduced while ensuring that the meshing part 1225g and the parking gear 1225a can engage and disengage completely.

[0081] As one implementation, the parking mechanism 1225 also includes an elastic element 1225j, one end of which abuts against the first transmission member 1225d, and the other end of which abuts against the second transmission member 1225e. When the meshing portion 1225g abuts against the teeth of the parking gear 1225a, if the parking gear 1225a rotates, the meshing portion 1225g can engage in the tooth groove between two adjacent teeth under the action of the elastic element 1225j.

[0082] Specifically, the elastic element 1225j is a torsion spring, which forms an annular mounting portion 1225k (see...). Figure 10 The mounting part 1225k is fitted onto the second transmission component 1225e, and the center line of the mounting part 1225k coincides with the axis of the fixed shaft 1225c.

[0083] With the above configuration, when the meshing part 1225g abuts against the parking gear 1225a, the elastic element 1225j is compressed to accumulate elastic potential energy. When the parking gear 1225a rotates, the elastic potential energy is converted into kinetic energy, pushing the meshing part 1225g into the tooth groove. When the toothed structure 1225h of the meshing part 1225g abuts against the tooth tip of the parking gear 1225a, if the wheel rotates under the influence of inertia or gravity, the output shaft 1223 can rotate under the drive of the wheel, and drive the parking gear 1225a to rotate synchronously. This allows the meshing part 1225g to have its toothed structure 1225h inserted into the tooth groove of the parking gear 1225a from the tooth tip under the elastic force applied by the elastic member 1225j. As described above, this avoids the problem of wear between the meshing part 1225g and the gear teeth. Furthermore, when the meshing part 1225g abuts against the parking gear 1225a, the operator does not need to continue to apply force, reducing the difficulty of parking.

[0084] In one implementation, the first transmission member 1225d includes an unlocking part 1225m extending toward the engagement part 1225g. When the parking cam 1225b rotates along the first direction F1, the second transmission member 1225e rotates around the fixed shaft 1225c under the action of the elastic member 1225j. When the parking cam 1225b rotates along the second direction F2, the unlocking part 1225m abuts against the engagement part 1225g and applies a force away from the parking gear 1225a to the engagement part 1225g. The first direction F1 is opposite to the second direction F2.

[0085] In the implementation of this application, there is no need to set up a complex structure. By setting up the unlocking part 1225m, the engaging part 1225g can be separated from the parking gear 1225a. The structure for releasing the parking gear 1225a from locking is simpler. Moreover, the unlocking part 1225m acts directly on the engaging part 1225g, which can reduce the torque required to disengage the engaging part 1225g from the parking gear 1225a.

[0086] Specifically, the first transmission member 1225d forms an annular structure 1225n, with an abutment portion 1225f located on the inner edge of the annular structure 1225n. The parking cam 1225b is located within the space formed by the annular structure 1225n, and a protrusion 1225p is provided on the outer edge of the parking cam 1225b. When the parking cam 1225b rotates in the first direction, the protrusion 1225p abuts against the abutment portion 1225f and drives the first transmission member 1225d to rotate, causing the meshing portion 1225g to mesh with the parking gear 1225a. When the parking cam 1225b rotates in the second direction, the protrusion 1225p abuts against the inner edge of the annular structure 1225n and drives the first transmission member 1225d to rotate, causing the meshing portion 1225g to separate from the parking gear 1225a.

[0087] Furthermore, a groove is formed on the outer edge of the protruding structure 1225p, and the groove is formed in the middle of the outer edge of the protruding structure 1225p.

[0088] The above arrangement creates a space for the annular structure 1225n and provides a groove for the protruding structure 1225p, thereby reducing the weight of the parking mechanism 1225.

[0089] In one implementation, the housing forms a cavity for housing the gear shift mechanism 1222 and the output shaft 1223, while the parking mechanism 1225 is installed outside the cavity. The input shaft 1221 and the gear set 1224 are both housed within the cavity.

[0090] In the implementation of this application, the parking mechanism 1225 is installed on the outer wall of the housing, which reduces the required volume of the accommodating cavity and thus reduces the size of the housing. If the parking mechanism 1225 needs to be inspected or replaced, it can be directly disassembled and installed without opening the housing, improving the convenience of inspecting and replacing the parking mechanism 1225.

[0091] like Figure 12 As shown, specifically, the parking mechanism 1225 also includes a parking linkage 1225q and a drive gear 1225r. At least a portion of the parking linkage 1225q passes through the housing and extends outside the housing. The drive gear 1225r is connected to the parking linkage 1225q and is located outside the housing. The drive gear 1225r is drive-connected to the parking cam 1225b.

[0092] like Figure 12As shown, in one implementation, in the vertical direction of the powertrain 100, the rotation center line of the transmission hub 1222a has a first height difference H1 with the axis of the input shaft 1221, and the rotation center line of the transmission hub 1222a has a second height difference H2 with the axis of the output shaft 1223. The ratio of the first height difference H1 to the second height difference H2 ranges from 0.9 to 1.42. Further, the ratio ranges from 1 to 1.28. More preferably, the ratio ranges from 1.12 to 1.14.

[0093] It should be noted that if the ratio of the first height difference H1 to the second height difference H2 is too large, since the parking mechanism 1225 is located outside the housing, the input shaft 1221 and output shaft 1223 will occupy too much space in the vertical direction of the powertrain 100, wasting space above the input shaft 1221 and increasing the volume of the housing. If the ratio is too small, it will cause damage to the transmission gear set 1224 and shifting jamming. Through the above settings, the volume of the housing is reduced while avoiding problems such as damage to the transmission gear set 1224 and shifting jamming.

[0094] like Figure 13 As shown, this application also provides an all-terrain vehicle 10, which includes a frame 200, a suspension system 400, a running system 300, and a steering system 500. The suspension system 400 includes a front suspension 41 connected to the frame 200. The running system 300 includes a front wheel 31 and a rear wheel 32 connected to the front suspension 41. The steering system 500 includes a steering handle 51, a steering drive mechanism (not shown), and a steering tie rod (not shown). The steering handle 51 pulls the steering tie rod laterally through the steering drive mechanism, causing the steering tie rod to deflect the front wheel 31.

[0095] As one implementation, the all-terrain vehicle 10 also includes the powertrain 100 in any of the above embodiments, the powertrain 100 being supported by the frame 200 and driving the front wheels 31 and / or the rear wheels 32.

[0096] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A powertrain, comprising: engine; A gearbox includes a housing, an input shaft, a shifting mechanism, an output shaft, and a transmission gear set. The gearbox is connected to the engine via the input shaft. The shifting mechanism includes a transmission hub and a shift fork connected to the transmission hub. The input shaft, output shaft, and transmission hub are all supported by the housing. The transmission gear set is connected between the input shaft and the output shaft. The end of the shift fork facing away from the transmission hub acts on the transmission gear set and can change the transmission ratio of the transmission gear set. The gearbox is characterized in that it further includes a parking mechanism, the parking mechanism comprising: A parking gear is fitted onto the output shaft and fixedly connected to it. The parking cam is coaxially connected to the transmission hub. A fixed shaft is fixed to the housing and located between the parking gear and the parking cam, the axis of the fixed shaft being parallel to the axis of the output shaft; A first transmission member is mounted on the fixed shaft. The first transmission member surrounds the parking cam and has an abutment portion extending toward the parking cam. When the parking cam rotates to a predetermined position, the parking cam can abut against the abutment portion and drive the first transmission member to rotate around the fixed shaft. The second transmission component is mounted on the fixed shaft and connected to the first transmission component. The end of the second transmission component facing away from the fixed shaft forms a meshing part. The second transmission component can engage the meshing part with the parking gear by rotating, or the second transmission component can disengage the meshing part by rotating the first transmission component.

2. The powertrain according to claim 1, characterized in that, The distance between the rotation center line of the transmission hub and the axis of the fixed shaft is defined as the first distance, and the distance between the rotation center line of the transmission hub and the axis of the output shaft is defined as the second distance. The ratio of the first distance to the second distance is in the range of 0.47 to 0.

72.

3. The powertrain according to claim 1, characterized in that, Viewed along the axial direction of the fixed shaft, the line connecting the axis of the output shaft to the axis of the fixed shaft is defined as the first extension line, and the line connecting the axis of the fixed shaft to the rotation center line of the transmission hub is defined as the second extension line. The angle between the first extension line and the second extension line is in the range of 25° to 40°.

4. The powertrain according to claim 1, characterized in that, The parking mechanism also includes an elastic element, one end of which abuts against the first transmission element and the other end of which abuts against the second transmission element. When the meshing part abuts against the teeth of the parking gear, if the parking gear rotates, the meshing part can be engaged in the tooth groove between two adjacent teeth under the action of the elastic element.

5. The powertrain according to claim 4, characterized in that, The elastic element is a torsion spring, which forms an annular mounting portion. The mounting portion is fitted onto the second transmission element, and the center line of the mounting portion coincides with the axis of the fixed shaft.

6. The powertrain according to claim 4, characterized in that, The first transmission member includes an unlocking part extending toward the engagement part. When the parking cam rotates in a first direction, the second transmission member rotates around the fixed axis under the action of the elastic member. When the parking cam rotates in a second direction, the unlocking part abuts against the engagement part and applies a force away from the parking gear to the engagement part. The first direction is opposite to the second direction.

7. The powertrain according to claim 6, characterized in that, The first transmission member forms an annular structure, the abutting part is located on the inner edge of the annular structure, the parking cam is located in the space formed by the annular structure, and the outer edge of the parking cam is provided with a protruding structure. When the parking cam rotates along the first direction, the protruding structure can abut against the abutting part and drive the first transmission member to rotate, so that the meshing part meshes with the parking gear. When the parking cam rotates in the second direction, the protruding structure abuts against the inner edge of the annular structure and drives the first transmission member to rotate, causing the meshing part to separate from the parking gear.

8. The powertrain according to claim 1, characterized in that, The housing forms a storage cavity for accommodating the gear shifting mechanism and the output shaft, and the parking mechanism is installed outside the storage cavity; The parking mechanism further includes a parking linkage and a drive gear. At least a portion of the parking linkage passes through the housing and extends outside the housing. The drive gear is connected to the parking linkage and is located outside the housing. The drive gear is drively connected to the parking cam.

9. The powertrain according to claim 8, characterized in that, In the vertical direction of the powertrain, the rotation center line of the transmission hub has a first height difference with the axis of the input shaft, and the rotation center line of the transmission hub has a second height difference with the axis of the output shaft. The ratio of the first height difference to the second height difference ranges from 0.9 to 1.

42.

10. An all-terrain vehicle, comprising: Frame; A walking system, at least partially located below the vehicle frame; A suspension system that connects the running gear to the vehicle frame; The all-terrain vehicle is characterized in that it further includes the powertrain according to any one of claims 1-9, the powertrain being supported by the vehicle frame and used to drive the walking system.

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