Three-gear electric drive axle structure of single gear shifting sliding sleeve

Abstract

The utility model relates to a three-gear electric drive axle structure of a single gear shifting sliding sleeve, a speed reducing mechanism comprises a first-stage driven gear, a gear shifting shaft, a third-stage driving gear shaft and a three-gear gear pair, a third-stage driving shaft gear is fixedly arranged on the third-stage driving gear shaft, and the three-gear gear pair comprises a driving gear and a driven gear corresponding to each gear. The first-level driven gear is fixedly arranged on the gear shifting shaft, the gear shifting shaft is sleeved with the driving gears of the three gears in an idle mode, the driven gears of the three gears are fixed to the third-level driving gear shaft, the driven gears of the three gears are connected with the corresponding driving gears respectively, and the gear shifting mechanism is arranged on the gear shifting shaft. The gear shifting mechanism performs gear shifting by being meshed with gears of different gears. By means of the single gear shifting executing mechanism and the single gear shifting sliding sleeve, output of three different speed ratios can be achieved, the gear shifting executing mechanism or a clutch and the like do not need to be additionally arranged, and the cost is more advantageous.

Description

Technical Field

[0001] The utility model relates to an electric drive axle, in particular to a three-speed electric drive axle structure with a single gear shift sliding sleeve. Background Art

[0002] Nowadays, with the continuous development of new energy drive technology, highly integrated electric drive axles are gradually being used in commercial vehicles. The difficulty in developing electric drive axle systems lies in arranging as many gear reduction mechanisms as possible within the limited space of the bridge housing, while taking into account the requirements of lightweight, climbing and high-speed driving. At present, pure electric heavy-duty commercial trucks mostly use central integrated electric drive axle drive to achieve vehicle power transmission, and the electric drive axle layout is mostly offset parallel axis and coaxial layout.

[0003] Patent CN116533732A provides a parallel shaft structure three-speed reducer drive structure, using three shift clutch structures, the shift controller is electrically connected to the first and second gear clutches and the third gear clutch, and is used to control the gear selection of the first and second gear clutches and the third gear clutch. Patent CN117141224A provides a parallel arrangement of multi-speed integrated electric drive axle assembly drive structure, using three shift mechanisms to control different meshing gear pairs to transmit power, so as to achieve multi-speed switching. Patent CN117341462A provides a parallel shaft + planetary gear coaxial output electric drive axle assembly, in which the shift elements are respectively combined with different driving gears, and the gear ring is controlled by the clutch to achieve gear change.

[0004] Patent CN117183626A provides a coaxial single-motor three-speed sequential shift electric drive axle system that uses a shift actuator and a shift gear sleeve to achieve sequential switching of three gears without power interruption. The shift gear sleeve has a first gear sleeve dog tooth, a second gear sleeve dog tooth, a third gear sleeve dog tooth and a fourth gear sleeve dog tooth; they are respectively engaged with the second-stage ring gear dog teeth and the first-stage ring gear dog teeth to achieve first-speed transmission; the third gear sleeve dog teeth and the second gear sleeve can be simultaneously engaged with the second-stage planetary carrier dog teeth and the first-stage ring gear dog teeth to achieve second-speed transmission; the fourth gear sleeve dog teeth and the second gear sleeve dog teeth can be simultaneously engaged with the first-stage planetary carrier dog teeth and the first-stage ring gear dog teeth to achieve three-speed transmission. The shift gear sleeve and the double planetary gear row structure are relatively complex; Patent CN115384304A provides a coaxial double planetary gear row structure, which realizes gear switching through a two-coupling gear shifter and a shift sliding sleeve. Patent CN116101054A provides an electric drive axle with a three-speed transmission mechanism. The double-star planetary gear cooperates with the original two-speed structure actuator to achieve the third gear, and the shift spline sleeve is rigidly connected to the sun gear coaxially.

[0005] Patent CN117048246A provides a coaxial three-speed dual-motor electric drive axle structure, which is equipped with a first shifter and a second shifter, which respectively drive the first shift fork to move and the second shift fork to move, thereby realizing three-speed switching.

[0006] However, the problems with the above structure are also obvious. Although the use of planetary gears for deceleration can increase the overall speed ratio, the power of each gear needs to pass through the planetary gears when it is used, and the transmission efficiency is not high. The parallel shaft transmission efficiency is high, but there are too many shift mechanisms and transmission stages, which not only increases the envelope size of the electric drive axle, making the layout of the whole vehicle difficult, but also reduces the overall transmission efficiency. At the same time, a single shift actuator can only realize the layout switching of two gears. When the gear needs to be increased, a shift actuator or a clutch needs to be added to achieve it. This will lead to a complex system structure and low transmission efficiency. It is impossible to take into account the multi-gear / low-cost electric heavy truck scenarios with high torque climbing and high-speed operation. Summary of the invention

[0007] The technical problem to be solved by the utility model is: a three-speed electric drive axle structure with a single shift sliding sleeve to solve the application problem of heavy truck integrated electric drive axle in the prior art.

[0008] The technical solution to solve the above technical problems is: a three-speed electric drive axle structure with a single shift sliding sleeve, comprising a motor, an input shaft gear, a differential, a reduction mechanism and a shift mechanism, wherein the motor, the input shaft gear, the differential, the reduction mechanism and the shift mechanism are respectively arranged on the axle housing, the reduction mechanism is connected to the motor through the input shaft gear, the shift mechanism is arranged on the reduction mechanism, the differential is connected to the reduction structure, the reduction mechanism comprises a primary driven gear, a shift shaft, a three-stage driving gear shaft and a gear pair of three gears, a three-stage driving shaft gear is fixedly provided with a three-stage driving shaft, the gear pair of three gears comprises a driving gear and a driven gear corresponding to each gear, the primary driven gear is fixedly arranged on the shift shaft, the driving gears of the three gears are idly sleeved on the shift shaft, the driven gears of the three gears are fixed on the three-stage driving gear shaft, the driven gears of the three gears are respectively connected to the corresponding driving gears, the shift mechanism is arranged on the shift shaft, and the shift mechanism performs shifting by meshing with gears of different gears.

[0009] The further technical scheme of the utility model is: the gear pair of three gears includes a two-stage first gear driving gear, a two-stage second gear driving gear, a two-stage third gear driving gear, a first gear driven gear, a second gear driven gear and a third gear driven gear, and the two-stage first gear driving gear, the two-stage second gear driving gear and the two-stage third gear driving gear are respectively connected to the shift mechanism through a combination tooth. The first-stage driven gear is connected to the motor through the input shaft gear, the two-stage first gear driving gear, the two-stage second gear driving gear and the two-stage third gear driving gear are respectively sleeved on the shift shaft, the first gear driven gear, the second gear driven gear and the third gear driven gear are respectively fixedly arranged on the three-stage driving gear shaft, the first gear driven gear, the second gear driven gear and the third gear driven gear are respectively meshed with the corresponding two-stage first gear driving gear, the two-stage second gear driving gear and the two-stage third gear driving gear, the three-stage driving shaft gear is connected to the three-stage driven gear, and the three-stage driven gear is connected to the differential.

[0010] The coupling teeth include first gear coupling teeth, second gear coupling teeth and third gear coupling teeth which are respectively fixedly connected to the second-stage first gear driving gear, the second-stage second gear driving gear and the second-stage third gear driving gear. The second-stage third gear driving gear is loosely mounted on the second-stage second gear driving gear.

[0011] The second-stage first-gear driving gear is fixedly connected to the first-gear combining teeth, the second-stage second-gear driving gear is fixedly connected to the second-gear combining teeth, the second-stage third-gear driving gear is fixedly connected to the third-gear combining teeth, and the second-stage third-gear driving gear and the third-gear combining teeth are loosely sleeved on the connecting shaft sleeve between the second-stage second-gear driving gear and the second-gear combining teeth.

[0012] The shift mechanism includes a shift sleeve, a shift actuator and a shift fork. The shift sleeve is connected to the shift actuator through the shift fork. The shift sleeve is sleeved on the outer spline of the shift shaft. The left and right ends of the shift sleeve are provided with inner splines. Different gears can be switched by moving the shift sleeve left and right.

[0013] Due to the adoption of the above technical solution, the three-speed electric drive axle structure with a single shift sleeve of the utility model has the following beneficial effects:

[0014] 1. The utility model can achieve outputs of three different speed ratios through a single shift actuator and a single shift sleeve, without the need to add a shift actuator or a clutch, etc., and has a more cost-effective approach. At the same time, the structural layout is simpler, which is more beneficial to the overall layout and inclusion of the electric drive axle reducer. The utility model solves the problems in the prior art that the planetary gear reduction structure has low transmission efficiency, too many parallel shaft shift mechanisms and transmission stages, and when three-stage reduction needs to be achieved, a shift actuator or a clutch needs to be added, which results in a complex system structure, increases the envelope size of the electric drive axle, makes the layout of the entire vehicle difficult, and reduces the overall transmission efficiency, making it impossible to take into account the use scenarios of high-torque climbing and high-speed operation of multi-gear / low-cost electric heavy trucks.

[0015] 2. The utility model adopts a parallel shaft integrated structure and a three-stage cylindrical gear reduction. The three-stage cylindrical gear reduction has a relatively small number of transmission stages and a high transmission efficiency. The shift shaft is the shift shaft, the space layout is more compact, and the existing traditional bridge housing and wheel rim are utilized, which can effectively reduce the weight and cost of the powertrain.

[0016] 3. The utility model adopts a single-motor multi-speed electric drive bridge structure, relying on the shift actuator and the sliding sleeve to achieve low, medium and high speed three-speed output, taking into account the torque and speed requirements when the vehicle starts, which can reduce the weight and volume of the motor and provide good vehicle dynamic performance, improve cruising range and other effects.

[0017] Next, the technical features of a three-speed electric drive axle structure with a single shift sleeve of the utility model will be further described in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 : Schematic diagram of a three-speed electric drive axle structure with a single shift sleeve.

[0019] In the above drawings, the descriptions of the reference numerals are as follows:

[0020] 10-motor, 11-input shaft gear, 21-first-stage driven gear, 22-second-stage first-gear driving gear, 23-second-stage second-gear driving gear, 24-second-stage third-gear driving gear, 25-first-gear combining tooth, 26-second-gear combining tooth, 27-third-gear combining tooth, 28-shift shaft, 29-shift sliding sleeve, 31-third-stage driving shaft gear, 32-first-gear driven gear, 33-second-gear driven gear, 34-third-gear driven gear, 40-differential, 41-third-stage driven gear, 51-shift actuator, 52-shift fork, 61-left half shaft, 62-right half shaft, 71-left wheel end, 72-right wheel end. DETAILED DESCRIPTION

[0021] A three-speed electric drive axle with a single shift sliding sleeve comprises a motor, an input shaft gear, a differential, a reduction mechanism and a shift mechanism, wherein the motor, the input shaft gear, the differential, the reduction mechanism and the shift mechanism are respectively arranged on the axle housing, the reduction mechanism is connected to the motor through the input shaft gear, the shift mechanism is arranged on the reduction mechanism, the differential is connected to the reduction structure, the reduction mechanism comprises a primary driven gear 21, a shift shaft, a three-stage driving gear shaft and gear pairs of three gears, a three-stage driving shaft gear 31 is fixedly arranged on the three-stage driving gear shaft, the gear pairs of the three gears comprise a driving gear and a driven gear corresponding to each gear, the primary driven gear 21 is fixedly arranged on the shift shaft, the driving gears of the three gears are idly sleeved on the shift shaft, the driven gears of the three gears are fixed on the three-stage driving gear shaft, the driven gears of the three gears are respectively connected to the corresponding driving gears, the shift mechanism is arranged on the shift shaft, and the shift mechanism performs shifting by meshing with gears of different gears.

[0022] The gear pair of three gears includes a two-stage first gear driving gear 22, a two-stage second gear driving gear 23, a two-stage third gear driving gear 24, a first gear driven gear 32, a second gear driven gear 33 and a third gear driven gear 34. The two-stage first gear driving gear 22, the two-stage second gear driving gear 23 and the two-stage third gear driving gear 24 are respectively connected to the shift mechanism through coupling teeth. The first-stage driven gear 21 is connected to the motor through the input shaft gear, the second-stage first-gear driving gear 22, the second-stage second-gear driving gear 23, and the second-stage third-gear driving gear 24 are respectively sleeved on the shift shaft 28, the first-gear driven gear 32, the second-gear driven gear 33, and the third-gear driven gear 34 are respectively fixedly arranged on the third-stage driving gear shaft, the first-gear driven gear 32, the second-gear driven gear 33, and the third-gear driven gear 34 are respectively meshed with the corresponding second-stage first-gear driving gear 22, the second-stage second-gear driving gear 23, and the second-stage third-gear driving gear 24, the third-stage driving shaft gear 31 is connected to the third-stage driven gear 41, and the third-stage driven gear 41 is connected to the differential.

[0023] The coupling teeth include a first gear coupling tooth 25, a second gear coupling tooth 26, and a third gear coupling tooth 27 which are respectively fixedly connected to the second-stage first gear driving gear 22, the second-stage second gear driving gear 23, and the second-stage third gear driving gear 24, and the second-stage third gear driving gear 24 is loosely sleeved on the second-stage second gear driving gear 23. The second-stage first gear driving gear 22 is fixedly connected to the first gear coupling tooth 25, the second-stage second gear driving gear 23 is fixedly connected to the second gear coupling tooth 26, the second-stage third gear driving gear 24 is fixedly connected to the third gear coupling tooth 27, and the second-stage third gear driving gear 24 and the third gear coupling tooth 27 are loosely sleeved on the connecting shaft sleeve between the second-stage second gear driving gear 23 and the second gear coupling tooth 26.

[0024] The shift mechanism includes a shift sleeve 29, a shift actuator 51 and a shift fork 52. The shift sleeve 29 is connected to the shift actuator 51 through the shift fork 52. The shift sleeve 29 is sleeved on the external spline of the shift shaft. Internal splines are provided on the left and right ends of the shift sleeve 29. Different gears can be switched by moving the shift sleeve 29 left and right. For example, referring to the attached drawings, when the shift sleeve 29 moves to the right, it meshes with the first gear combining tooth 25. At this time, the two ends of the shift sleeve 29 are respectively meshed with the outer spline of the shift shaft and the first gear combining tooth 25, which is the first gear state. The shift shaft drives the second-stage first gear driving gear 22 to rotate through the shift sleeve 29, thereby driving the first gear driven gear 32 to rotate, and then drives the third-stage driving gear shaft and the third-stage driving shaft gear 31 to rotate; when the shift sleeve 29 moves to the left, it meshes with the second gear combining tooth 26. At this time, the two ends of the shift sleeve 29 are respectively meshed with the outer spline of the shift shaft and the second gear combining tooth 26, which is the second gear state. The shift shaft drives the second-stage first gear driving gear 22 to rotate through the shift sleeve 29, thereby driving the first gear driven gear 32 to rotate, and then drives the third-stage driving gear shaft and the third-stage driving shaft gear 31 to rotate; The sliding sleeve 29 drives the secondary second gear driving gear 23 to rotate, thereby driving the second gear driven gear 33 to rotate, and then driving the third gear driving gear shaft and the third gear driving shaft gear 31 to rotate; the shift sliding sleeve 29 moves to the left again when it is in the second gear state, and at this time the shift sliding sleeve 29 is meshed with the third gear combining tooth 27, and at this time the two ends of the shift sliding sleeve 29 are respectively meshed with the outer spline of the shift shaft and the third gear combining tooth 27, which is in the third gear state, and the shift shaft drives the secondary third gear driving gear 24 to rotate through the shift sliding sleeve 29, thereby driving the third gear driven gear 34 to rotate, and then driving the third gear driving gear shaft and the third gear driving shaft gear 31 to rotate.

[0025] Specific embodiment: A shifting method for a three-speed electric drive bridge with a single shift sleeve, comprising a motor 10, an input shaft gear 11, a primary driven gear 21, a secondary first gear driving gear 22, a secondary second gear driving gear 23, a secondary third gear driving gear 24, a first gear combining gear 25, a second gear combining gear 26, a third gear combining gear 27, a shift shaft 28, a shift sleeve 29, a shift actuator 51, a shift fork 52, a third gear driving gear shaft, a third gear driving shaft gear 31, a first gear driven gear 32, a second gear driven gear 33, a third gear driven gear 34, a differential 40, a third gear driven gear 41, a left half shaft 61, a right half shaft 62, a left wheel end 71 and a right wheel end 72. The input shaft gear 11 is connected to the motor 10 input, and the power is transmitted from the motor 10 and transmitted to the primary driven gear 21 by the input shaft gear 11. This power transmission is the first stage reduction i1. The primary driven gear 21 is fixedly connected to the shift shaft 28, and the primary driven gear 21 and the shift shaft 28 can be fixedly connected by interference fit. The secondary first gear driving gear 22, the secondary second gear driving gear 23, and the secondary third gear driving gear 24 are all loosely sleeved on the shift shaft 28. When the shift shaft is in neutral, the rotation of the shift shaft will not drive the driving gears of the three gears to rotate. The secondary first gear driving gear 22, the secondary second gear driving gear 23, and the secondary third gear driving gear 24 are respectively in a constant meshing state with the corresponding secondary first gear driven gear 32, the secondary second gear driven gear 33, and the secondary first gear driven gear 34. This power transmission is the second stage reduction i2, that is, the primary driven gear 21 is transmitted to the third stage driving shaft gear 31 through the corresponding gears of each gear in the three gears, forming the second stage reduction ratio i2, and the speed ratios of different gear pairs in different gears are respectively i 21 、i 22 、i 23 The third-stage driving shaft gear 31 meshes with the third-stage driven gear 41, and the power transmission is the third-stage reduction i3. Finally, the power is transmitted to both sides of the bridge through the differential 40, and output to the left half shaft 61, the right half shaft 62, the left wheel end 71, and the right wheel end 72.

[0026] The second-stage first-gear driving gear 22, the second-stage second-gear driving gear 23, and the second-stage third-gear driving gear 24 are fixedly connected with the first-gear combining teeth 25, the second-gear combining teeth 26, and the third-gear combining teeth 27, respectively. The driving gears of each gear and the corresponding combining teeth can be integrated into an integral structure, or can be fixedly connected by welding. The first-gear combining teeth 25, the second-gear combining teeth 26, and the third-gear combining teeth 27 are respectively arranged with external splines that cooperate with the shift sleeve. The shift sleeve 29 is sleeved on the external splines of the shift shaft 28 through internal splines, and can slide left and right under the action of external force. The left and right ends of the shift sleeve 29 are respectively provided with internal splines, and there is no spline in the middle position. When the vehicle is shifting through the external VCU and TCU, the shift actuator 51 drives the shift fork 52 to move, controlling the shift sleeve 29 to move left and right. The shift sleeve 29 is in different positions, and the shift shaft 28 can be connected to different combination teeth (first gear combination teeth 25, second gear combination teeth 26, and third gear combination teeth 27), thereby realizing the selection of different secondary master and slave gear ratios i 21 、i 22 、i 23 Output, thereby outputting different speed ratios to achieve shift control and switching. At the same time, a gap is set between the adjacent gears of the first gear coupling tooth 25, the second gear coupling tooth 26, and the third gear coupling tooth 27 on the shift shaft 28, and the gear shifting is realized in 3-N-2-N-1, which effectively ensures the controllability and smoothness of the switching process.

[0027] Furthermore, the total reduction ratio of the reducer is defined as i, and the reduction ratios of the first-stage reduction, the second-stage reduction, and the third-stage reduction are i1, i2, and i3 respectively. 21 / i 22 / i 23 , i3, then: when the shift sleeve is spline-connected with the first gear engaging teeth, the second-stage first gear driving gear 22 and the second-stage first gear driven gear 32 are meshed, and the output is 1st gear. At this time, the total reduction ratio i=i1×i 21 ×i3. When the shift sleeve is spline-connected with the second gear engaging teeth, the second-stage second gear driving gear 23 and the second-stage second gear driven gear 33 are meshed, and the output is 2nd gear. At this time, the total reduction ratio i=i1×i 22 ×i3. When the shift sleeve is spline-connected with the third gear engaging teeth, the second-stage third gear driving gear 24 and the second-stage first gear driven gear 34 are meshed, and the output is 3rd gear. At this time, the total reduction ratio i=i1×i 21 ×i3.

[0028] The purpose of adapting the multi-speed electric drive axle to the high-speed and low-torque motor is achieved on heavy-duty trucks. A large speed ratio is used at low speeds, and a small speed ratio is used at high speeds. The relationship between the motor speed and the vehicle speed is reasonably controlled so that the motor runs in the high-efficiency speed range most of the time, providing good vehicle dynamic performance and improving the cruising range.

Claims

1. A three-speed electric drive axle structure with a single shift sleeve, comprising a motor, an input shaft gear, a differential, a speed reduction mechanism and a shift mechanism, wherein the speed reduction mechanism is connected to the motor through the input shaft gear, the shift mechanism is arranged on the speed reduction mechanism, and the differential is connected to the speed reduction mechanism, characterized in that: The reduction mechanism includes a primary driven gear, a shift shaft, a third driving gear shaft and a gear pair for three gears. A third driving shaft gear is fixedly provided on the third driving gear shaft. The gear pair for the three gears includes a driving gear and a driven gear corresponding to each gear. The primary driven gear is fixedly provided on the shift shaft. The driving gears for the three gears are loosely mounted on the shift shaft. The driven gears for the three gears are fixed on the third driving gear shaft. The driven gears for the three gears are respectively connected with the corresponding driving gears. The shift mechanism is provided on the shift shaft. The shift mechanism shifts gears by meshing with gears of different gears.

2. A three-speed electric drive axle structure with a single shift sleeve according to claim 1, characterized in that: The gear pair of three gears includes a two-stage first-gear driving gear, a two-stage second-gear driving gear, a two-stage third-gear driving gear, a first-gear driven gear, a second-gear driven gear and a third-gear driven gear. The two-stage first-gear driving gear, the two-stage second-gear driving gear and the two-stage third-gear driving gear are respectively connected to the shift mechanism through a coupling tooth.

3. A three-speed electric drive axle structure with a single shift sleeve according to claim 2, characterized in that: The coupling teeth include first gear coupling teeth, second gear coupling teeth and third gear coupling teeth which are respectively fixedly connected to the second-stage first gear driving gear, the second-stage second gear driving gear and the second-stage third gear driving gear. The second-stage third gear driving gear is loosely mounted on the second-stage second gear driving gear.

4. A three-speed electric drive axle structure with a single shift sleeve according to claim 3, characterized in that: The second-stage second-gear driving gear is fixedly connected to the second-gear combining teeth, the second-stage third-gear driving gear is fixedly connected to the third-gear combining teeth, and the second-stage third-gear driving gear and the third-gear combining teeth are loosely sleeved on the connecting shaft sleeve between the second-stage second-gear driving gear and the second-gear combining teeth.

5. The three-speed electric drive axle structure with a single shift sleeve according to claim 1, characterized in that: The shift mechanism includes a shift sleeve, a shift actuator and a shift fork. The shift sleeve is connected to the shift actuator through the shift fork. The shift sleeve is sleeved on the outer spline of the shift shaft. The left and right ends of the shift sleeve are provided with inner splines. Different gears can be switched by moving the shift sleeve left and right.

Images