Integral differential device of double-planet-row mechanism

Abstract

The utility model provides a double-planet-row mechanism integral differential device. The double-planet-row mechanism integral differential device comprises a first planet gear mechanism and a second planet gear mechanism, and the second planetary gear mechanism is in transmission connection with the first planetary gear mechanism, and the second planetary gear mechanism is of an axially-arranged double-row structure. According to the planetary gear differential device, the radial size of the planetary gear differential device can be controlled, so that the inertia of the planetary gear differential device is reduced, and potential risks in the using process are reduced.

Description

Technical Field

[0001] This application relates to the technical field of vehicle transmission mechanisms, and particularly to an integral differential device with a double planetary gear set mechanism. Background Art

[0002] A differential device is used in a vehicle drive system to distribute torque to the two wheels on both sides of the vehicle. It usually has an input end for introducing torque into it and two output ends for leading torque out from it. New energy vehicles adopt an integral planetary gear differential device to achieve the lateral arrangement of the motor reduction device. The existing integral planetary gear differential device has too large a radial dimension, resulting in too large an inertia of the planetary gear differential device and a relatively high potential risk during use. Summary of the Utility Model

[0003] This application provides an integral differential device with a double planetary gear set mechanism to control the radial dimension of the integral planetary gear differential device, thereby reducing the inertia of the planetary gear differential device and lowering the potential risk during use.

[0004] This application provides an integral differential device with a double planetary gear set mechanism, which includes:

[0005] A first planetary gear mechanism;

[0006] A second planetary gear mechanism, which is in transmission connection with the first planetary gear mechanism, and the second planetary gear mechanism is an axially arranged double-row structure.

[0007] Optionally, the first planetary gear mechanism includes a first planet carrier, a sun gear, and a first ring gear. The first planet carrier is installed with a plurality of first planet gears. The first ring gear is coaxially arranged with the sun gear. The first planet gears are respectively meshed with the sun gear and the first ring gear. The sun gear forms a power input end, and the first planet carrier forms a first power output end;

[0008] The second planetary gear mechanism includes a second planet carrier, a second ring gear, and a third ring gear;

[0009] The second planet carrier is installed with a plurality of second planet gears. The second double planet gears include a first meshing section and a second meshing section arranged axially. The plurality of second planet gears form a double planet gear train;

[0010] The second ring gear is coaxially arranged with the sun gear, and the first meshing section is meshed with the second ring gear;

[0011] The third ring gear is coaxially arranged with the sun gear, and the second meshing section is meshed with the third ring gear;

[0012] The second ring gear is a fixed part. Among the second planet carrier and the third ring gear, one of them is relatively fixed to the first ring gear, and the other forms a second power output end.

[0013] Optionally, the second planet carrier includes a main body portion and an end cover connected to each other. The second planet gear is installed between the main body portion and the end cover. The first ring gear is integrally connected to the end cover, and the third ring gear forms the second power output end.

[0014] Optionally, a first extension portion is provided at the center of the end cover. The first extension portion is annular and axially protrudes from the side of the end cover facing the main body portion. The first ring gear is integrally formed on the inner wall of the first extension portion.

[0015] Optionally, a first recessed portion is provided on the side of the main body portion facing away from the end cover;

[0016] The center of the third ring gear is embedded in the first recessed portion and forms the second power output end.

[0017] Optionally, the transmission ratio of the first planetary gear mechanism is i1, and the transmission ratio of the second planetary gear mechanism is i2. The relationship between i1 and i2 is 1 + 2i1 = i1 * i2.

[0018] Optionally, an end plate is provided at one end of the third ring gear away from the first meshing section. The first ring gear is integrally connected to the end plate, and the second planet carrier forms the second power output end.

[0019] Optionally, a second extension portion is provided at the center of the end plate. The second extension portion is annular and axially protrudes from the side of the end plate facing the third ring gear. The first ring gear is integrally formed on the inner wall of the second extension portion.

[0020] Optionally, a second recessed portion is provided at one end of the second planet carrier away from the end plate, and the second recessed portion forms the second power output end.

[0021] Optionally, both the second ring gear and the third ring gear are disposed outside the second planet gear.

[0022] The technical solution provided by this application can achieve the following beneficial effects:

[0023] The dual planetary gear mechanism integral differential device provided in the embodiment of the present application includes a first planetary gear mechanism and a second planetary gear mechanism, and the second planetary gear mechanism is connected to the first planetary gear mechanism in a transmission manner, so as to realize both deceleration and torque increase and differential function at the same time, so as to meet the driving requirements of the vehicle; the second planetary gear mechanism is an axially arranged double-row structure, that is, the second planetary gear mechanism and the first planetary gear mechanism form an axial stacking arrangement, so that the dual planetary gear mechanism integral differential device is axially extended and radially reduced, which can reduce the radial size of the dual planetary gear mechanism integral differential device, thereby reducing the inertia of the planetary differential device and reducing the potential risks during use. In addition, the present application axially extends and radially reduces the second planetary gear mechanism with a larger radial size, thereby realizing the axial extension and radial reduction of the dual planetary gear mechanism integral differential device, with relatively small changes and low costs. Moreover, the first planetary gear mechanism and the second planetary gear mechanism are two independent components, which can be disassembled and separated from each other and assembled with each other, which can reduce the complexity of the dual planetary gear mechanism integral differential device and minimize the defective rate of assembly and production line.

[0024] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of the structure of a dual planetary gear mechanism integral differential device provided in an embodiment of the present application;

[0026] Figure 2 for Figure 1 Schematic diagram of the structure from another angle;

[0027] Figure 3 for Figure 1 The lever principle diagram of the integral differential device of the double planetary gear mechanism shown;

[0028] Figure 4 for Figure 1 The first structural diagram of the double planetary gear mechanism integral differential device shown;

[0029] Figure 5 for Figure 1 The second structural diagram of the double planetary gear mechanism integral differential device shown;

[0030] Figure 6 for Figure 1 The third structural diagram of the double planetary gear mechanism integral differential device shown;

[0031] Figure 7 A schematic diagram of the structure of another dual planetary gear mechanism integral differential device provided in an embodiment of the present application;

[0032] Figure 8is Figure 7 Partial structural schematic diagram of

[0033] Figure 9 is Figure 7 Lever principle diagram of the overall differential device of the double planetary gear train mechanism shown in

[0034] Figure 10 is Figure 7 The first structural schematic diagram of the overall differential device of the double planetary gear train mechanism shown in

[0035] Figure 11 is Figure 7 The second structural schematic diagram of the overall differential device of the double planetary gear train mechanism shown in

[0036] Figure 12 is Figure 7 The third structural schematic diagram of the overall differential device of the double planetary gear train mechanism shown in

[0037] Reference numerals:

[0038] 1 - First planetary gear mechanism;

[0039] 11 - First planet carrier;

[0040] 12 - Sun gear;

[0041] 13 - First ring gear;

[0042] 14 - First planetary gear;

[0043] 2 - Second planetary gear mechanism;

[0044] 21 - Second planet carrier;

[0045] 211 - Main body part;

[0046] 2111 - First recessed part;

[0047] 212 - End cover;

[0048] 2121 - First extended part;

[0049] 213 - Second recessed part;

[0050] 22 - Second ring gear;

[0051] 23 - Third ring gear;

[0052] 231 - End plate;

[0053] 2311 - Second extended part;

[0054] 24 - Second planetary gear;

[0055] 241 - First meshing segment;

[0056] 242 - Second engagement section;

[0057] 3 - Electric motor;

[0058] 4 - Half shaft;

[0059] 5 - Wheel.

[0060] The accompanying drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application. Detailed implementation manners

[0061] In order to make the objectives, technical solutions and advantages of this application more clearly understood, the following further details this application in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0062] In the description of this application, unless otherwise clearly specified and defined, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance; unless otherwise specified or stated, the term "plurality" means two or more; terms such as "connection" and "fixation" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0063] In the description of this specification, it should be understood that the orientation terms such as "upper" and "lower" described in the embodiments of this application are described from the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. In addition, in the context, it should also be understood that when it is mentioned that one element is connected "above" or "below" another element, it can not only be directly connected "above" or "below" another element, but also be indirectly connected "above" or "below" another element through an intermediate element.

[0064] As Figures 1 - 12As shown in the figure, an overall differential device for a dual planetary gear train provided by an embodiment of the present application is applied to a vehicle, and it includes a first planetary gear mechanism 1 and a second planetary gear mechanism 2. The radial dimension of the second planetary gear mechanism 2 is larger than that of the first planetary gear mechanism 1. The second planetary gear mechanism 2 is drivingly connected to the first planetary gear mechanism 1, so as to realize the functions of speed reduction, torque increase and differential, and meet the driving requirements of the vehicle. The second planetary gear mechanism 2 is an axially arranged double-row structure, that is to say, the second planetary gear mechanism 2 and the first planetary gear mechanism 1 are arranged in an axially stacked manner, so that the overall differential device of the dual planetary gear train is axially extended and radially reduced, which can reduce the radial dimension of the overall differential device of the dual planetary gear train, thereby reducing the inertia of the planetary differential device and reducing the potential risks during use. In addition, in the embodiment of the present application, the second planetary gear mechanism 2 with a larger radial dimension is axially extended and radially reduced, so as to realize the axial extension and radial reduction of the overall differential device of the dual planetary gear train, with less modification and lower cost. Moreover, the first planetary gear mechanism 1 and the second planetary gear mechanism 2 are two independent components, and they can be disassembled, separated and assembled with each other, which can reduce the complexity of the overall differential device of the dual planetary gear train and minimize the defective rate of the assembly and production line.

[0065] Specifically, the first planetary gear mechanism 1 forms a power input end and a first power output end, and the second planetary gear mechanism 2 forms a second power output end. The power input end is used to connect a driving mechanism such as a motor 3, the first power input end is used to connect one half shaft 4 of the vehicle, and the second power output end is used to connect the other half shaft 4 of the vehicle. The half shaft 4 is connected to the wheel 5.

[0066] Among them, the first planetary gear mechanism 1 includes a first planet carrier 11, a sun gear 12 and a first ring gear 13. A plurality of first planet gears 14 are installed on the first planet carrier 11, and the first planet gears 14 are rotatably connected to the planet carrier; the first ring gear 13 is coaxially arranged with the sun gear 12, and the first planet gears 14 are respectively meshed with the sun gear 12 and the first ring gear 13, and the first planet gears 14 can rotate around the sun gear 12 together with the first planet carrier 11. The sun gear 12 forms a power input end, and the first planet carrier 11 forms a first power output end.

[0067] Further, the second planetary gear mechanism 2 includes a second planet carrier 21, a second ring gear 22, and a third ring gear 23. The second planet carrier 21 is mounted with a plurality of second planet gears 24. The second planet gears 24 are rotatably connected to the planet carrier. The second planet gears 24 include a first meshing segment 241 and a second meshing segment 242 arranged along the axial direction. The plurality of second planet gears 24 form a double planetary gear train. Specifically, the first meshing segment 241 and the second meshing segment 242 respectively form a planetary gear train, and the two planetary gear trains rotate synchronously; the second ring gear 22 meshes with the first meshing segment 241, and the third ring gear 23 meshes with the second meshing segment 242. By setting the second planet gear 24 into a segmented structure arranged axially, not only can the radial dimension of the overall differential device of the double planetary row mechanism be reduced, but also the expected transmission ratio requirements can be met. The second ring gear 22 is a fixed member, that is to say, the second ring gear 22 can be fixedly connected to the housing or the vehicle body to realize the overall installation and fixation of the overall differential device of the double planetary row mechanism; among the second planet carrier 21 and the third ring gear 23, one of them is relatively fixed to the first ring gear 13 (for example, fixedly connected or integrally formed, etc.), and the other forms a second power output end, so that the torque input by the sun gear 12 can be transmitted to the second planetary gear mechanism 2 through the first ring gear 13, so that torque distribution can be performed on the two half shafts 4 as needed.

[0068] Further, both the second ring gear 22 and the third ring gear 23 surround the outside of the second planet gear 24, that is to say, both the second ring gear 22 and the third ring gear 23 are provided with tooth-shaped structures on the inner side, rather than on both the inner and outer sides of the ring gear, making the force distribution of the ring gear more reasonable and reducing the risk of damage to the ring gear.

[0069] As Figures 1 - 6 shown, in some embodiments, the first ring gear 13 is relatively fixed to the second planet carrier 21, so that the first ring gear 13 and the second planet carrier 21 are coupled. The first ring gear 13 and the second planet carrier 21 rotate at the same speed and with the same torque. The first ring gear 13 serves as the output member of the first planetary gear mechanism 1, which is equivalent to the second planet carrier 21 forming the input member of the second planetary gear mechanism 2, and the third ring gear 23 forms the second power output end.

[0070] Further, the transmission ratio of the first planetary gear mechanism 1 is i1, and the transmission ratio of the second planetary gear mechanism 2 is i2. The relationship between i1 and i2 is 1 + 2i1 = i1 * i2, so that the torque input by the sun gear 12 can be evenly distributed to the first power output end and the second power output end, thereby ensuring that both wheels 5 on both sides can obtain sufficient torque to provide sufficient traction force to ensure that the vehicle can drive smoothly, while reducing the problems that may occur when the vehicle turns.

[0071] Furthermore, the overall transmission ratio of the double planetary gear set differential device is \(i\), and \(i = n_{s1} / n_{pc1}=(1 + i_1)\times i_2 / (i_2 - 1)\). The magnitude of the overall transmission ratio \(i\) affects aspects such as the vehicle's acceleration performance, driving stability, and fuel economy, and can be reasonably selected according to needs to meet the design requirements and performance demands.

[0072] Specifically, in combination with Figure 3 , the derivation process of the above relational expression is as follows:

[0073] \(i_1 = Z\) R1 / Z S1 , \(i_2 = Z\) P3 *Z r2 / (Z R3 *Z P2 );

[0074] T S1 * \(i_1 = T\) R1 *1 -> T R1 = \(i_1\times T\) S1 ;

[0075] T R1 = T PC2 -> T PC2 = \(i_1\times T\) S1 ;

[0076] T PC1 *1 = (\(i_1 + 1\))*T S1 → T PC1 = (\(1 + i_1\))*T S1 ;

[0077] T PC2 *1 = T R3 *( \(i_2 - 1\));

[0078] ∴ T R3 = 1 / ( \(i_2 - 1\))*T PC2 = \(i_1\) / ( \(i_1 - 1\))*T S1 ;

[0079] 1 + \(i_1\) = \(i_1\)*( \(i_2 - 1\)) → 1 + 2\(i_1\) = \(i_1\)*\(i_2\)+\(i_2\);

[0080] \(i = n_{s1} / n_{pc1}=(1 + i_1)\times i_2 / (i_2 - 1)\).

[0081] Among them, \(i_1\) is the speed ratio of the first-stage planetary gear set, \(i_2\) is the speed ratio of the second-stage planetary gear set, \(Z\) is the number of teeth, \(T\) is the torque, \(n\) is the rotational speed; \(R\) is the ring gear, \(S\) is the sun gear 12, and \(PC\) is the planet carrier.

[0082] Furthermore, the second planet carrier 21 includes a main body portion 211 and an end cover 212 that are connected to each other. The second planet gear 24 is installed between the main body portion 211 and the end cover 212. The first ring gear 13 is integrally connected to the end cover 212, making full use of the original structure of the second planet carrier 21 and reducing the processing cost of the overall differential device of the double planetary row mechanism.

[0083] In one embodiment, referring to Figure 4 , a through hole is provided in the center of the end cover 212, and the first ring gear 13 is integrally formed on the inner wall of the through hole. This can not only simplify the structure of the end cover 212 and reduce the production cost, but also enable the end cover 212 to directly form a radial support around the outer wall of the first ring gear 13, which is beneficial to ensuring the stability of the ring gear and reducing abnormalities such as vibration and deformation that may occur in the ring gear.

[0084] In another embodiment, referring to Figure 5 , a first extension portion 2121 is provided in the center of the end cover 212. The first extension portion 2121 is annular, and the first extension portion 2121 axially protrudes from the side of the end cover 212 facing the main body portion 211. The first ring gear 13 is integrally formed on the inner wall of the first extension portion 2121, so that the first planetary gear mechanism 1 moves axially into the inner cavity of the second planetary gear mechanism 2 together with the first ring gear 13, thereby reducing the axial dimension of the overall differential device of the double planetary row mechanism and making the overall structure more compact.

[0085] Furthermore, referring to Figure 6 , a first recessed portion 2111 is provided on the side of the main body portion 211 facing away from the end cover 212. The center of the third ring gear 23 is embedded in the first recessed portion 2111 and forms a second power output end. That is to say, the half shaft 4 is connected within the first recessed portion 2111, which also reduces the distance between the two side wheels 5 and meets the installation requirements of vehicles with a small axial space.

[0086] As Figures 7 - 12 shown, in some other embodiments, the first ring gear 13 and the third ring gear 23 are relatively fixed, so that the first ring gear 13 and the third ring gear 23 are coupled. The third ring gear 23 rotates at the same speed and with the same torque as the first ring gear 13. The first ring gear 13 serves as the output member of the first planetary gear mechanism 1 and is equivalent to the third ring gear 23 forming the input member of the second planetary gear mechanism 2. The second planet carrier 21 forms a second power output end.

[0087] Further, the transmission ratio of the first planetary gear mechanism 1 is i1, and the transmission ratio of the second planetary gear mechanism 2 is i2. The relationship between i1 and i2 is 1 + 2i1 = i1 * i2 + i2, so that the torque input by the sun gear 12 can be evenly distributed to the first power output end and the second power output end, ensuring that the wheels 5 on both sides can obtain sufficient torque to provide sufficient traction and ensuring the smooth driving of the vehicle. At the same time, the problems that may occur when the vehicle turns are reduced.

[0088] Further, the total transmission ratio of the double planetary row mechanism integral differential device is i, i = ns1 / npc1 = (1 + i1) / (1 / i2) → i = (1 + i1) * i2. The magnitude of the total transmission ratio i affects aspects such as the acceleration performance, driving stability, and fuel economy of the vehicle, and can be reasonably selected according to needs to meet the design requirements and performance requirements.

[0089] Specifically, referring to Figure 9 , the derivation process of the above relational expression is as follows:

[0090] i1 = Z R1 / Z S1 , i2 = (Z P3 *Z R2 ) / (Z R3 *Z P2 );

[0091] T S1 *i1 = T R1 *1, T R1 = i1 * T S1 ;

[0092] T R1 = T R3 , T R3 = i * T S1 ;

[0093] T S1 *(i1 + 1) = T PC1 *1 → T PC1 = (1 + i1) * T S1 ;

[0094] T R3 *(i2 - 1) = T PC2 *1 → T PC2 = (i2 - 1) * T R3 ;

[0095] ∴T PC2 = (i2 - 1) * i1 * T S1 ;

[0096] (1 + i1) = i1 * (i2 - 1) → 1 + 2i1 = i1 * i2;

[0097] i = ns1 / npc1 = (1 + i1) / (1 / i2) → i = (1 + i1) * i2.

[0098] Wherein, i1 is the speed ratio of the first planetary gear set, i2 is the speed ratio of the second planetary gear set, Z is the number of teeth, T is the torque, n is the rotational speed; R is the ring gear, S is the sun gear 12, and PC is the planetary carrier.

[0099] Furthermore, one end of the third ring gear 23 away from the first engagement section 241 is provided with an end plate 231, and the first ring gear 13 is integrally connected with the end plate 231, so that the third ring gear 23 and the first ring gear 13 are connected through the end plate 231 to form a whole, which can play a role in radial support and strengthening for the first ring gear 13 and the third ring gear 23, and prevent the first ring gear 13 or the second ring gear 22 from deforming.

[0100] Specifically, the first ring gear 13 and the end plate 231 can be connected to each other by connecting parts such as splines, or can be integrally formed by methods such as one-time sharpening; similarly, the third ring gear 23 and the end plate 231 can be connected to each other by connecting parts such as splines, or can be integrally formed by methods such as one-time sharpening.

[0101] In one embodiment, referring to Figure 10 , the end plate 231 is arranged in a ring structure, and the first ring gear 13 is integrally formed on the inner ring of the end plate 231, which can not only simplify the structure of the end plate 231 and reduce the production cost, but also enable the end plate 231 to directly form a radial support around the outer wall of the first ring gear 13, which is beneficial to ensuring the stability of the ring gear and reducing abnormalities such as vibration and deformation that the ring gear may generate.

[0102] In another embodiment, referring to Figure 11 , the center of the end plate 231 is provided with a second extension part 2311, the second extension part 2311 is annular, the second extension part 2311 axially protrudes from the side of the end plate 231 facing the third ring gear 23, and the first ring gear 13 is integrally formed on the inner wall of the second extension part 2311, so that the first planetary gear mechanism 1 moves axially into the inner cavity of the second planetary gear mechanism 2 together with the first ring gear 13, thereby reducing the axial dimension of the overall differential device of the double planetary gear set mechanism and making the overall structure more compact.

[0103] Furthermore, referring to Figure 12 , one end of the second planetary carrier 21 away from the end plate 231 is provided with a second recess 213, and the second recess 213 forms a second power output end. That is to say, the half shaft 4 is connected within the second recess 213, which also reduces the distance between the two side wheels 5 and meets the installation requirements of vehicles with a small axial space.

[0104] In addition, an embodiment of the present application further provides a vehicle, which includes any one of the overall differential devices of the double planetary gear train mechanism provided by the embodiment of the present application. By using the overall differential device of the double planetary gear train mechanism provided by the embodiment of the present application, the requirements of decelerating and increasing torque at the same time and the differential function can be achieved, meeting the driving needs of the vehicle. The torque density of the present invention can reach 70 Nm / kg, and the peak torque can reach more than 4000 Nm. In addition, by using the overall differential device of the double planetary gear train mechanism provided by the embodiment of the present application, a unique compact space can be formed (saving about 25% of the space), making the overall differential device of the double planetary gear train mechanism lighter in weight (saving about 10% of the mass), lower in power consumption (20% of the power consumption), and better in NVH performance.

[0105] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. An overall differential device for a double planetary gear train mechanism, characterized in that, Comprising: A first planetary gear mechanism; A second planetary gear mechanism, which is in transmission connection with the first planetary gear mechanism, and the second planetary gear mechanism is an axially arranged double-row structure.

2. The integral differential device of the double planetary row mechanism according to claim 1, wherein The first planetary gear mechanism includes a first planet carrier, a sun gear and a first ring gear. A plurality of first planet gears are installed on the first planet carrier. The first ring gear is coaxially arranged with the sun gear. The first planet gears are respectively meshed with the sun gear and the first ring gear. The sun gear forms a power input end, and the first planet carrier forms a first power output end; The second planetary gear mechanism includes a second planet carrier, a second ring gear and a third ring gear; A plurality of second planet gears are installed on the second planet carrier. The second planet gears include a first meshing section and a second meshing section arranged axially. The plurality of second planet gears form a double planet gear train; The second ring gear is coaxially arranged with the sun gear, and the first meshing section is meshed with the second ring gear; The third ring gear is coaxially arranged with the sun gear, and the second meshing section is meshed with the third ring gear; The second ring gear is a fixed part. Among the second planet carrier and the third ring gear, one of them is relatively fixed to the first ring gear, and the other forms a second power output end.

3. The overall differential device of the double planetary gear set according to claim 2, wherein, The second planet carrier includes a main body part and an end cover connected to each other. The second planet gears are installed between the main body part and the end cover. The first ring gear is integrally connected with the end cover, and the third ring gear forms the second power output end.

4. The overall differential device of the double planetary gear train mechanism according to claim 3, characterized in that, A first extension part is provided at the center of the end cover. The first extension part is annular. The first extension part axially protrudes from the side of the end cover facing the main body part. The first ring gear is integrally formed on the inner wall of the first extension part.

5. The overall differential device of the double planetary gear set according to claim 3, characterized in that, A first recessed part is provided on the side of the main body part facing away from the end cover; The center of the third ring gear is embedded in the first recessed part and forms the second power output end.

6. The overall differential device of the double planetary gear train mechanism according to claim 3, characterized in that, The transmission ratio of the first planetary gear mechanism is i1, the transmission ratio of the second planetary gear mechanism is i2, and the relationship between i1 and i2 is 1 + 2i1 = i1 * i2.

7. The overall differential device of the double planetary gear set according to claim 2, characterized in that, An end plate is provided at one end of the third ring gear away from the first meshing section. The first ring gear is integrally connected with the end plate, and the second planet carrier forms a second power output end.

8. The overall differential device of the double planetary gear train mechanism according to claim 7, characterized in that, A second extension part is provided at the center of the end plate. The second extension part is annular. The second extension part axially protrudes from the side of the end plate facing the third ring gear. The first ring gear is integrally formed on the inner wall of the second extension part.

9. The overall differential device of the double planetary gear train mechanism according to claim 7, characterized in that, A second recessed part is provided at one end of the second planet carrier away from the end plate, and the second recessed part forms the second power output end.

10. The overall differential device of the double planetary gear train mechanism according to any one of claims 2-9, characterized in that, Both the second ring gear and the third ring gear surround the outside of the second planet gears.

Images