A single-planet wheel type three-gear reducer assembly, an electric drive axle and a vehicle

Abstract

The embodiment of the application discloses a single-planet-wheel type three-gear speed reducer assembly, an electric drive axle and a car. The speed reducer assembly comprises an input shaft, a first gear reduction mechanism, a second gear reduction mechanism, a first synchronizer, a second synchronizer, a center shaft and a planetary gear train. The input shaft is drivingly connected to the center shaft through the first gear reduction mechanism. The first synchronizer is fixed on the center shaft and can slide axially along the center shaft to change the speed reduction ratio of the first gear reduction mechanism. The second synchronizer is fixed on the center shaft and can slide axially along the center shaft to change the speed reduction ratio of the second gear reduction mechanism. The center shaft is drivingly connected to a sun gear shaft of the planetary gear train. The carrier of the planetary gear train is used as an output end. The coaxial planetary gear train and the parallel shaft gear combination transmission have stronger power and torque bearing capacity. The overall layout is more compact, the vehicle space occupation is reduced, the power transmission path is simplified, and the construction cost is reduced.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a single planetary gear type three-speed reducer assembly, an electric drive axle, and an automobile. Background Technology

[0002] Currently, the drive systems applicable to vehicles are broadly divided into two types: central drive and electric drive axle. Among them, the central drive system has been widely used in heavy-duty trucks. Similar to traditional models, it generally uses an electric motor with a multi-speed reducer, and connects to the rear axle through a drive shaft to achieve power transmission. The structure is relatively simple, but it occupies a large space, which is not conducive to freeing up battery space and affects the vehicle's range. Therefore, many OEMs have begun to start research on electric drive axles.

[0003] The electric drive axle inherits the electric channel system and rear axle, which can greatly free up battery space, while reducing the overall vehicle weight and lowering costs. Electric drive axle products in related technologies are broadly divided into two types based on the axle housing form: one-piece stamped and welded axle housings that can use traditional axle housings, and segmented axle housings that integrate the motor, reducer, and differential. Segmented axle housings are widely used due to their high integration and small size.

[0004] However, segmented axle housing electric drive axles are expensive because they often use large motors with small-ratio reducers. Furthermore, traditional layouts are not conducive to power distribution, result in large system mass, and have a dispersed overall layout, occupying a significant amount of vehicle space. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a single planetary gear type three-speed reducer assembly, an electric drive axle, and an automobile. It employs a synchronizer-optimized design structure to achieve multiple reducer gears by implementing different power transmission paths.

[0006] The embodiments of this application disclose the following technical solutions:

[0007] In a first aspect, embodiments of this application disclose a single planetary gear type three-speed reducer assembly, comprising:

[0008] Input shaft, first gear reduction mechanism, second gear reduction mechanism, first synchronizer, second synchronizer, central shaft and planetary gear train;

[0009] The input shaft is connected to the central shaft via the first gear reduction mechanism;

[0010] The first synchronizer is fixed on the central shaft and can slide along the central shaft axially to change the reduction ratio of the first gear reduction mechanism;

[0011] The second synchronizer is fixed on the central shaft and can slide along the central shaft axially to change the reduction ratio of the second gear reduction mechanism;

[0012] The central shaft is connected to the sun gear shaft of the planetary gear train; the planet carrier of the planetary gear train serves as the output end.

[0013] Optionally, the second gear reduction mechanism includes a first gear reduction structure and a second gear reduction structure; the reduction ratios of the first gear reduction structure and the second gear reduction structure are different.

[0014] The second synchronizer is fixed on the central shaft and can slide axially along the central shaft to change the reduction ratio of the second gear reduction mechanism, including:

[0015] The second synchronizer is fixed on the central shaft and can slide along the central shaft axially. It can be connected to the first gear reduction structure or the second gear reduction structure to achieve different reduction ratios.

[0016] Optionally, each of the gear reduction structures includes a driving gear and a driven gear;

[0017] The number of teeth on the driving gear is less than the number of teeth on the driven gear that meshes with it.

[0018] Optionally, the first synchronizer and the second synchronizer slide along the central axis, switching between the first gear, the second gear, the third gear, and the neutral position:

[0019] When the reducer assembly is in the first gear position, the first synchronizer is suspended, and the second synchronizer is connected to the first gear reduction structure.

[0020] When the reducer assembly is in the second gear position, the first synchronizer is suspended, and the second synchronizer is connected to the second gear reduction structure.

[0021] When the reducer assembly is in the third gear position, the first synchronizer is connected to the first gear reduction mechanism, and the second synchronizer is suspended.

[0022] When the reducer assembly is in the neutral position, both the first synchronizer and the second synchronizer are suspended.

[0023] Secondly, embodiments of this application disclose an electric drive bridge, including a bridge housing and a reducer assembly disposed within the bridge housing, wherein the reducer assembly adopts a single planetary gear type three-speed reducer assembly as described in the first aspect and any option thereof.

[0024] Optionally, the electric drive bridge further includes a drive motor, which is connected to the input shaft in a driving connection.

[0025] Optionally, the drive motor is connected to the input shaft via a spline.

[0026] Thirdly, embodiments of this application disclose an automobile including an electric drive axle, wherein the electric drive axle is an electric drive axle as described in the second aspect and any alternative to the second aspect.

[0027] As can be seen from the above technical solutions, by adopting a combination of coaxial planetary gear train and parallel shaft gear transmission, it has a stronger load-bearing capacity for power and torque distribution; and the overall layout is more compact, reducing the space occupied in the vehicle; by arranging the motor and intermediate shaft on both sides of the assembly, the overall center of gravity coordinate is closer to the shaft center, reducing the impact load on the electric drive axle caused by road impact; finally, the use of a multi-stage gear long meshing structure to achieve multi-stage reduction simplifies the power transmission path and reduces construction costs. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A simplified structural diagram of a single planetary gear type three-speed reducer assembly for an electric drive axle provided in this application embodiment;

[0030] Figure 2 A mid-position power transmission diagram of a single planetary gear type three-speed reducer assembly for an electric drive axle provided in an embodiment of this application;

[0031] Figure 3 A power transmission diagram of the first gear of a single planetary gear type three-speed reducer assembly for an electric drive axle provided in an embodiment of this application;

[0032] Figure 4 A power transmission diagram for the second gear of a single planetary gear type three-speed reducer assembly for an electric drive axle provided in this application embodiment;

[0033] Figure 5 This application provides a power transmission diagram for the third gear of a single planetary gear type three-speed reducer assembly for an electric drive axle, as shown in an embodiment of the present application. Detailed Implementation

[0034] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] Without loss of generality, this embodiment is based on Figure 1 The single planetary gear three-speed reducer assembly shown is used as the main description subject to detail the power path optimization implementation scheme that can be used for electric drive axles. It should be understood that the specific number of teeth of each gear component in this power path is not the core inventive point of this application and does not constitute a substantial limitation on the single planetary gear two-speed reducer assembly claimed in this application.

[0036] Please see Figure 1 , Figure 1 This is a simplified structural diagram of a single planetary gear type three-speed reducer assembly for an electric drive axle provided in an embodiment of this application.

[0037] In the picture:

[0038] Output: Power output; C: Central shaft / output shaft; Synchronizer 1: First synchronizer; Synchronizer 2: Second synchronizer;

[0039] O: Sun gear; X: Planet carrier; F: Planet gear; O, X, and F constitute the planetary gear train;

[0040] 11: Third driving gear, 12: Third driven gear, A: Input shaft; The third driving gear 11 and the third driven gear 12 constitute the third gear reduction structure;

[0041] 21: Fourth driving gear, 22: Fourth driven gear, B: Shaft shared by the third driven gear 12 and the fourth driving gear 21; The fourth driving gear 21 and the fourth driven gear 22 constitute the fourth gear reduction structure;

[0042] The third gear reduction structure and the fourth gear reduction structure together form the first gear reduction mechanism.

[0043] 31: Intermediate gear;

[0044] 41: First driving gear; 42: First driven gear; The first driving gear 41 and the first driven gear 42 form a first gear reduction structure;

[0045] 51: Second driving gear; 52: Second driven gear; D: Shaft shared by intermediate gear 31, first driving gear 41 and second driving gear 51; Second driving gear 51 and second driven gear 52 form a second gear reduction structure;

[0046] The first gear reduction structure and the second gear reduction structure together form the second gear reduction mechanism.

[0047] This single planetary gear three-speed reducer assembly comprises a total of five reduction stages, with four gear reduction stages and a planetary gear reduction stage each completing one stage of reduction. The planetary gear reduction stage is configured so that the sun gear inputs power and the planet carrier outputs power.

[0048] Based on the drive motor, the embodiments of this application are configured with an input shaft corresponding to the drive motor, so that the power provided by the drive motor is introduced into the reducer assembly, and connected to the central shaft C through the first gear reduction structure and the second gear reduction mechanism. The central shaft C is connected to the sun gear O of the planetary gear train.

[0049] By employing a multi-stage gear reduction structure, a large reduction ratio can be achieved, realizing the function of increasing torque and reducing speed. The combination of coaxial planetary gear trains and parallel shaft gears provides stronger power and torque load capacity; the overall layout is more compact, reducing the space occupied in the vehicle; placing the motor and intermediate shaft on both sides of the assembly brings the overall center of gravity closer to the shaft center, reducing the impact load on the electric drive axle from road impacts; the use of a multi-stage gear long-mesh structure to achieve multi-stage reduction simplifies the power transmission path and reduces construction costs. Simultaneously, this structure, through the suspension and engagement of synchronizers, enables power splitting, increasing power density and improving vehicle performance and ride comfort.

[0050] It should be understood that the actual reduction ratio of the two gear reduction mechanisms between the two input shafts and the central shaft in this embodiment can be set according to the overall design requirements of the vehicle.

[0051] It is understood that, in order to achieve the torque increase and speed reduction function, the number of teeth of the driving gear in all the gear reduction structures mentioned in the embodiments of this application is less than the number of teeth of the driven gear meshing with it.

[0052] As one possible approach, the number of teeth on the driving gear and the number of teeth on the driven gear in the same gear reduction structure are coprime. This can prevent specific gears from meshing repeatedly, allowing the entire gear reduction structure to bear the wear caused by gear meshing on an average basis, thereby improving the service life of the gears.

[0053] Please see Figure 2 , Figure 2 This is a mid-position power transmission diagram of a single planetary gear type three-speed reducer assembly for an electric drive axle provided in an embodiment of this application.

[0054] in, Figure 2 The components represented by the component codes in the text are... Figure 1 The components are the same, and have been... Figure 1 The explanation is given in the middle, and Figure 3 and Figure 4 This is true for all of them. To avoid repetition, further details will be provided later. Figure 2 , Figure 3 and Figure 4 The description directly quotes the target Figure 1 For an explanation of the corresponding component codes, please refer to the preceding text if needed. Figure 1 The introduction in the text is sufficient; it will not be repeated here or thereafter.

[0055] and Figure 1 The difference is that, Figure 2 as well as Figure 3 , Figure 4 The dotted line represents the power transmission path, that is, the path through which power is transmitted from the input shaft to the output shaft and through various mechanical structures. The light-colored part indicates that the corresponding gear does not receive power transmission in this state.

[0056] in, Figure 2 The components represented by the component codes in the text are... Figure 1 The components are the same, and have been... Figure 1 The explanation is given in the middle, and Figure 3 , Figure 4 and Figure 5 This is true for all of them. To avoid repetition, further details will be provided later. Figure 2 , Figure 3 , Figure 4 and Figure 5 The description directly quotes the target Figure 1 For an explanation of the corresponding component codes, please refer to the preceding text if needed. Figure 1 The introduction in the text is sufficient; it will not be repeated here or thereafter.

[0057] and Figure 1 The difference is that, Figure 2 , Figure 3 , Figure 4 as well as Figure 5 The dotted line represents the power transmission path, that is, the path through which power is transmitted from the input shaft to the output shaft and through various mechanical structures.

[0058] exist Figure 2 In the middle, both the first synchronizer and the second synchronizer are suspended, forming the neutral position, i.e., the neutral position.

[0059] At this point, both the first and second synchronizers are disengaged from the gears and are in a suspended state. Figure 2 As shown by the dashed line, the power output from the motor is transmitted to the first drive gear 41 and the second drive gear 51 and then no longer transmitted to the next gear. The output shaft does not receive any power transmission, and the planetary gear train spins idly, so there is no power output, forming a neutral position.

[0060] Please see Figure 3 , Figure 3 This is a diagram showing the first gear power transmission of a single planetary gear type three-speed reducer assembly for an electric drive axle, provided as an embodiment of this application.

[0061] exist Figure 3 In the middle, the first synchronizer is suspended, the second synchronizer slides to the left axial direction, and the second synchronizer is connected to the first gear reduction structure.

[0062] In this embodiment, the third driving gear 11 and the third driven gear 12 on the input shaft mesh to achieve the first stage of speed reduction; the third driven gear 12 and the fourth driving gear 21 are connected to the shaft B via a spline, and the fourth driving gear 21 and the fourth driven gear 22 on the shaft B mesh to achieve the second stage of speed reduction; the intermediate gear 31 on the shaft D meshes with the fourth driven gear 22 to achieve the third stage of speed reduction; the second synchronizer slides axially to the left along the central shaft C, and the intermediate gear 31 is connected to the first driving gear 41 via a spline, and the first driving gear 41 meshes with the first driven gear 42 to achieve the fourth stage of speed reduction; the planetary gear F revolves around the sun gear O under the drive of the sun gear O, and outputs power through the planet carrier X to achieve the fifth stage of speed reduction.

[0063] Please see Figure 4 , Figure 4 This is a diagram showing the second gear power transmission of a single planetary gear type three-speed reducer assembly for an electric drive axle, provided as an embodiment of this application.

[0064] exist Figure 4 In the middle, the first synchronizer is suspended, the second synchronizer slides to the right axial direction, and the second synchronizer is connected to the second gear reduction structure.

[0065] In this implementation, the power transmission path from the input shaft to shaft D is the same as that of the first gear. The first and second stages of reduction are achieved before the power is transmitted to shaft D, which will not be elaborated here. Afterward, the second synchronizer slides axially to the right, connecting the intermediate gear 31 to the second driving gear 51 via a spline. The second driving gear 51 meshes with the second driving gear 52, achieving the third stage of reduction. The planetary gear F, driven by the sun gear O, revolves around the sun gear O, outputting power through the planet carrier X, achieving the fourth stage of reduction.

[0066] Please see Figure 5 , Figure 5 This application provides a diagram showing the third gear power transmission of a single planetary gear type three-speed reducer assembly for an electric drive axle, as shown in an embodiment of the present application.

[0067] exist Figure 5 In the middle, the second synchronizer is suspended, the first synchronizer slides to the right axial direction, and the first synchronizer is connected to the fourth gear reduction structure.

[0068] In this implementation, the power transmission path from the input shaft to the central shaft C is the same as that of the first gear. First and second stage reduction are achieved before the power is transmitted to the central shaft C, which will not be elaborated here. Afterward, the first synchronizer slides axially to the right, connecting the planetary gear F to the fourth driven gear 22 via a spline. Therefore, power is directly transmitted from the fourth driven gear 22 to the planetary gear F of the planetary gear train, and then through the planetary gear train to the planet carrier, where it is output via the planet carrier X.

[0069] In addition to the aforementioned single planetary gear three-speed reducer assembly, this application embodiment also provides an electric drive axle including the single planetary gear three-speed reducer assembly, which is disposed in the axle housing.

[0070] As one possible implementation, the electric drive bridge also includes a drive motor, which is connected to the input shaft.

[0071] As one possible implementation, the drive motor is connected to the input shaft via a spline.

[0072] It should be noted that the other functional components of the electric drive bridge are not the core inventive point of this application, and those skilled in the art can implement them based on existing technology, so this specification will not elaborate further.

[0073] In addition to the aforementioned electric drive axle, embodiments of this application also provide a vehicle including the electric drive axle. This vehicle can be a new energy heavy-duty truck or any other type of vehicle. It should be noted that other functional components of the vehicle are not the core inventive point of this application, and those skilled in the art can implement them based on existing technology; therefore, they will not be described in detail here.

[0074] In the description of this embodiment and its various implementations, terms such as "up," "down," "left," and "right" used to characterize direction are only used to describe the relative positions or relative operations of the components in the illustrated diagram. It is understood that these directional terms do not constitute a substantial limitation on this solution. Furthermore, as a possible implementation, the specific function of the shift gears can be a dog-tooth structure.

[0075] It should be noted that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0076] The above description is merely one specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A single planetary gear type three-speed reducer assembly, characterized in that, include: Input shaft, first gear reduction mechanism, second gear reduction mechanism, first synchronizer, second synchronizer, central shaft and planetary gear train; The first gear reduction mechanism includes a third gear reduction structure and a fourth gear reduction structure; The second gear reduction mechanism includes a first gear reduction structure and a second gear reduction structure; the reduction ratios of the first gear reduction structure and the second gear reduction structure are different. The input shaft is connected to the central shaft via the first gear reduction mechanism; The first synchronizer is fixed on the central shaft and can slide along the central shaft axially to change the reduction ratio of the first gear reduction mechanism; The second synchronizer is fixed on the central shaft and can slide along the central shaft axially. It can be connected to the first gear reduction structure or the second gear reduction structure to achieve different reduction ratios. The central shaft is connected to the sun gear shaft of the planetary gear train; the reducer assembly includes a five-stage reduction structure, namely, the first gear reduction structure, the second gear reduction structure, the third gear reduction structure, the fourth gear reduction structure and the planetary gear train reduction structure each complete a first-stage reduction, the planetary gear train reduction structure is configured to input power from the sun gear and output power from the planet carrier of the planetary gear train; The first synchronizer and the second synchronizer slide along the central axis, switching between the first gear, the second gear, the third gear and the neutral position; When the reducer assembly is in the first gear position, the first synchronizer is suspended, and the second synchronizer is connected to the first gear reduction structure. When the reducer assembly is in the second gear position, the first synchronizer is suspended, and the second synchronizer is connected to the second gear reduction structure. When the reducer assembly is in the third gear position, the first synchronizer is connected to the first gear reduction mechanism, and the second synchronizer is suspended. When the reducer assembly is in the neutral position, both the first synchronizer and the second synchronizer are suspended.

2. The single planetary gear type three-speed reducer assembly according to claim 1, characterized in that, Each of the gear reduction structures includes a driving gear and a driven gear; The number of teeth on the driving gear is less than the number of teeth on the driven gear that meshes with it.

3. An electric drive bridge, characterized in that, It includes an axle housing and a reducer assembly disposed within the axle housing, wherein the reducer assembly is a single planetary gear type three-speed reducer assembly as described in any one of claims 1-2.

4. The electric drive bridge according to claim 3, characterized in that, The electric drive bridge also includes a drive motor, which is connected to the input shaft in a transmission manner.

5. The electric drive bridge according to claim 4, characterized in that, The drive motor is connected to the input shaft via a spline.

6. A car, characterized in that, Includes an electric drive bridge, wherein the electric drive bridge is the electric drive bridge described in any one of claims 3-5.

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