Heavy duty 6x6 off-road vehicle four-gear hub electric drive system
By using a hub motor matched with a transmission drive system and a planetary transmission in a heavy-duty 6×6 off-road vehicle, and designing four forward gears, the problem of balancing the highest wheel speed and the maximum driving torque in the hub electric drive system was solved, achieving a wide transmission ratio range, system lightweighting, and increased power density.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA NORTH VEHICLE RES INST
- Filing Date
- 2024-10-30
- Publication Date
- 2026-04-17
AI Technical Summary
Existing hub electric drive systems with hub motors and reducers struggle to meet the requirements of both maximum wheel speed and maximum drive torque for off-road vehicles, resulting in low system power density. This contradiction is particularly pronounced in heavy-duty 6x6 off-road vehicles.
It adopts a hub motor matched with a transmission drive system, combining a hub motor and a planetary transmission, including transmission components, planetary gear set, brakes and one-way clutch, and is designed with four forward gears to achieve a transmission ratio range of over 6.0, meeting the needs of heavy-duty 6×6 off-road vehicles.
It achieves a gear ratio range of over 6.0 for four forward gears, solving the problem of balancing maximum wheel speed and maximum drive torque in heavy 6×6 off-road vehicles. The system is lightweight and has increased power density.
Smart Images

Figure CN119189650B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of electric drive technology for new energy vehicles, and specifically relates to a four-speed wheel hub electric drive system for a heavy-duty 6×6 off-road vehicle. Background Technology
[0002] In-wheel electric drive systems place the powertrain inside the vehicle's wheel rim, representing a distributed drive system. Currently, in-wheel electric drive systems mainly employ three forms: in-wheel motor direct drive, in-wheel motor paired with a reducer, and in-wheel motor paired with a transmission. Off-road vehicles primarily use the in-wheel motor paired with a reducer form.
[0003] Off-road vehicles operate under complex conditions, requiring higher driving torque from the wheels. Existing in-wheel electric drive systems with in-wheel motors and reducers struggle to balance the demands of maximum wheel speed and maximum output torque, resulting in excessively large design margins for the in-wheel motors and low system power density. Furthermore, with advancements in in-wheel motor technology, their rotational speeds are increasing, exacerbating this contradiction. Therefore, it is necessary to develop an in-wheel electric drive system with an in-wheel motor and transmission drive configuration. For a 20-ton heavy-duty 6x6 off-road vehicle, the forward gear ratio range must be at least 6.0. Summary of the Invention
[0004] (a) Technical problems to be solved
[0005] The technical problem this invention aims to solve is: how to provide a four-speed in-wheel electric drive system for heavy-duty 6×6 off-road vehicles, employing an in-wheel motor matched with a transmission to achieve four forward gears. First gear should meet the maximum output torque requirement of the in-wheel electric drive system, while fourth gear should meet the maximum wheel speed requirement, thus resolving the technical challenge of simultaneously achieving maximum wheel speed and maximum drive torque in off-road vehicles. Furthermore, the transmission ratio range of the forward gears should be wide, exceeding 6.0.
[0006] (II) Technical Solution
[0007] To solve the above-mentioned technical problems, the present invention provides a four-speed wheel hub electric drive system for heavy-duty 6×6 off-road vehicles, the four-speed wheel hub electric drive system for heavy-duty 6×6 off-road vehicles includes: a wheel hub motor (①) and a planetary transmission (②);
[0008] The hub motor (①) includes: a hub motor stator (8) and a hub motor rotor (9);
[0009] The planetary transmission (②) includes: a transmission component assembly, a planetary gear set assembly, a brake assembly, and a one-way clutch assembly;
[0010] The transmission component assembly includes: a first component (1), a second component (2), a third component (3), a fourth component (4), a fifth component (5), a sixth component (6), and a seventh component (7);
[0011] The planetary array assembly includes: a first planetary array PGS1, a second planetary array PGS2, and a third planetary array PGS3;
[0012] The brake assembly includes: a first brake B1 and a second brake B2;
[0013] The one-way clutch assembly includes: a first one-way clutch C1 and a second one-way clutch C2;
[0014] The hub motor rotor (9) is connected to the first component (1);
[0015] The hub motor stator (8) is connected to the seventh component (7);
[0016] The first planetary gear set PGS1 includes a first sun gear S1, a first planet carrier CA1 and a first gear ring R1, which are connected to the seventh component (7), the first component (1) and the fifth component (5) respectively;
[0017] The second planetary gear set PGS2 includes a second sun gear S2, a second planet carrier CA2, and a second gear ring R2, which are connected to the fifth component (5), the sixth component (6), and the fourth component (4), respectively.
[0018] The third planetary gear set PGS3 includes a third sun gear S3, a third planet carrier CA3, and a third gear ring R3, which are connected to the sixth component (6), the second component (2), and the third component (3), respectively.
[0019] The first brake B1 is used to brake the third component (3);
[0020] The second brake B2 is used to brake the fourth component (4);
[0021] The first one-way clutch C1 is used to connect the fourth component (4) and the second component (2);
[0022] The second one-way clutch C2 is used to connect the second component (2) and the sixth component (6).
[0023] When the first brake B1 and the second brake B2 are engaged, the third component (3) and the fourth component (4) brake to achieve first gear.
[0024] When the first one-way clutch C1 and the first brake B1 are engaged, the fourth component (4) and the second component (2) are connected and rotate as a whole, and the third component (3) brakes, thus achieving second gear.
[0025] When the second one-way clutch C2 and the second brake B2 are engaged, the second component (2) and the sixth component (6) rotate as a whole after being connected, and the fourth component (4) brakes, thus achieving three gears.
[0026] When the first one-way clutch C1 and the second one-way clutch C2 are engaged, the fourth component (4) and the second component (2) are connected and rotate as a whole. The second component (2) and the sixth component (6) are connected and rotate as a whole, thus achieving four gears.
[0027] The hub motor (①) is a permanent magnet synchronous inner rotor motor.
[0028] (III) Beneficial Effects
[0029] Compared to existing in-wheel electric drive systems for off-road vehicles that use in-wheel motors paired with reducers, the four-speed in-wheel electric drive system for heavy-duty 6×6 off-road vehicles proposed in this invention employs an in-wheel motor paired with a four-speed transmission, comprising an in-wheel motor and a planetary transmission. The in-wheel motor includes an in-wheel motor stator and an in-wheel motor rotor. The planetary transmission includes components 1-7, a first planetary gear set PGS1-PGS3, brakes B1-B2, and one-way clutches C1-C2, enabling four forward gears. The use of one-way clutches reduces the system's size and weight, achieving lightweight design. The transmission ratio range of the four forward gears can reach over 6.0, effectively solving the technical problem of simultaneously achieving the highest wheel speed and maximum driving torque in a 20-ton heavy-duty 6×6 off-road vehicle. Attached Figure Description
[0030] Figure 1 This is a schematic diagram of the four-speed wheel hub electric drive system for a heavy-duty 6×6 off-road vehicle according to the present invention.
[0031] Among them, ① is the hub motor, and ② is the planetary gearbox;
[0032] 1~7——First component, second component, third component, fourth component, fifth component, sixth component, seventh component;
[0033] PGS1, PGS2, and PGS3 – First Planetary Sorting, Second Planetary Sorting, and Third Planetary Sorting;
[0034] B1, B2 – First brake, second brake;
[0035] C1, C2 – First one-way clutch, second one-way clutch;
[0036] S1, CA1, R1 – the first sun gear, the first planet carrier, and the first gear ring of the first planetary gear set PGS1; S2, CA2, R2 – the second sun gear, the second planet carrier, and the second gear ring of the second planetary gear set PGS2; S3, CA3, R3 – the third sun gear, the third planet carrier, and the third gear ring of the third planetary gear set PGS3.
[0037] 8 – Stator of hub motor; 9 – Rotor of hub motor. Detailed Implementation
[0038] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.
[0039] To solve the above-mentioned technical problems, the present invention provides a four-speed wheel hub electric drive system for heavy-duty 6×6 off-road vehicles, the four-speed wheel hub electric drive system for heavy-duty 6×6 off-road vehicles includes: a wheel hub motor (①) and a planetary transmission (②);
[0040] The hub motor (①) includes: a hub motor stator (8) and a hub motor rotor (9);
[0041] The planetary transmission (②) includes: a transmission component assembly, a planetary gear set assembly, a brake assembly, and a one-way clutch assembly;
[0042] The transmission component assembly includes: a first component (1), a second component (2), a third component (3), a fourth component (4), a fifth component (5), a sixth component (6), and a seventh component (7);
[0043] The planetary array assembly includes: a first planetary array PGS1, a second planetary array PGS2, and a third planetary array PGS3;
[0044] The brake assembly includes: a first brake B1 and a second brake B2;
[0045] The one-way clutch assembly includes: a first one-way clutch C1 and a second one-way clutch C2;
[0046] The hub motor rotor (9) is connected to the first component (1);
[0047] The hub motor stator (8) is connected to the seventh component (7);
[0048] The first planetary gear set PGS1 includes a first sun gear S1, a first planet carrier CA1 and a first gear ring R1, which are connected to the seventh component (7), the first component (1) and the fifth component (5) respectively;
[0049] The second planetary gear set PGS2 includes a second sun gear S2, a second planet carrier CA2, and a second gear ring R2, which are connected to the fifth component (5), the sixth component (6), and the fourth component (4), respectively.
[0050] The third planetary gear set PGS3 includes a third sun gear S3, a third planet carrier CA3, and a third gear ring R3, which are connected to the sixth component (6), the second component (2), and the third component (3), respectively.
[0051] The first brake B1 is used to brake the third component (3);
[0052] The second brake B2 is used to brake the fourth component (4);
[0053] The first one-way clutch C1 is used to connect the fourth component (4) and the second component (2);
[0054] The second one-way clutch C2 is used to connect the second component (2) and the sixth component (6).
[0055] When the first brake B1 and the second brake B2 are engaged, the third component (3) and the fourth component (4) brake to achieve first gear.
[0056] When the first one-way clutch C1 and the first brake B1 are engaged, the fourth component (4) and the second component (2) are connected and rotate as a whole, and the third component (3) brakes, thus achieving second gear.
[0057] When the second one-way clutch C2 and the second brake B2 are engaged, the second component (2) and the sixth component (6) rotate as a whole after being connected, and the fourth component (4) brakes, thus achieving three gears.
[0058] When the first one-way clutch C1 and the second one-way clutch C2 are engaged, the fourth component (4) and the second component (2) are connected and rotate as a whole. The second component (2) and the sixth component (6) are connected and rotate as a whole, thus achieving four gears.
[0059] The hub motor (①) is a permanent magnet synchronous inner rotor motor.
[0060] Example
[0061] The heavy-duty 6×6 off-road vehicle four-speed hub electric drive system proposed in this embodiment includes a hub motor (①) and a planetary transmission (②), arranged horizontally from left to right. The first planetary gear set PGS1 of the planetary transmission (②) is nested inside the hub motor (①), as shown below. Figure 1 As shown.
[0062] The hub motor (①) includes a hub motor stator (8) and a hub motor rotor (9), and the planetary gearbox (②) includes components 1 to 7, planetary gearboxes PGS1 to PGS3, brakes B1 to B2, and one-way clutches C1 to C2.
[0063] The hub motor (①) can be a permanent magnet synchronous internal rotor motor. The hub motor rotor (9) is connected to the first component (1), and the hub motor stator (8) is connected to the seventh component (7).
[0064] The first planetary gear set PGS1 includes a first sun gear S1, a first planet carrier CA1 and a first ring gear R1, which are connected to the seventh component (7), the first component (1) and the fifth component (5) respectively; the second planetary gear set PGS2 includes a second sun gear S2, a second planet carrier CA2 and a second ring gear R2, which are connected to the fifth component (5), the sixth component (6) and the fourth component (4) respectively; the third planetary gear set PGS3 includes a third sun gear S3, a third planet carrier CA3 and a third ring gear R3, which are connected to the sixth component (6), the second component (2) and the third component (3) respectively.
[0065] The first brake B1 is used to brake the third component (3), and the second brake B2 is used to brake the fourth component (4); the first one-way clutch C1 is used to connect the fourth component (4) and the second component (2), and the second one-way clutch C2 is used to connect the second component (2) and the sixth component (6).
[0066] When the first brake B1 and the second brake B2 are engaged, the third component (3) and the fourth component (4) brake to achieve first gear;
[0067] When the first one-way clutch C1 and the first brake B1 are engaged, the fourth component (4) and the second component (2) are connected and rotate as a whole, and the third component (3) brakes, thus achieving second gear;
[0068] When the second one-way clutch C2 and the second brake B2 are engaged, the second component (2) and the sixth component (6) are connected and rotate as a whole, and the fourth component (4) brakes, thus achieving three gears;
[0069] When the first one-way clutch C1 and the second one-way clutch C2 are engaged, the fourth component (4) and the second component (2) are connected and rotate as a whole. The second component (2) and the sixth component (6) are connected and rotate as a whole, thus achieving four gears.
[0070] like Figure 1 In the embodiment shown, when the k values of the first planetary gear set PGS1 to PGS3 are k1 = -1.073, k2 = 1.50 and k3 = 1.50 respectively, the parameters of the four gears can be obtained, as listed in the table below.
[0071]
[0072] Note: In the table, “〇” indicates that the control element is engaged, and “×” indicates that the control element is disengaged.
[0073] In this example, planetary gear sets PGS2 and PGS3 adopt equal k-value structural design parameters. The gear tooth parameters of the sun gear, planet gears, and ring gear of the two planetary gear sets can be designed uniformly, reducing the types of gears, lowering gear processing costs, and improving the system's economy. In this example, the transmission ratio range of the four forward gears is wider, reaching 6.25, which can meet the usage requirements of a 20-ton heavy-duty 6×6 off-road vehicle.
[0074] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principle of the present invention and without changing the connection relationship, such as changing the arrangement position of the planetary gear set and the one-way clutch, or modifying the first planetary gear set into a simple double-planet gear set. These improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A four-speed wheel hub electric drive system for a heavy-duty 6×6 off-road vehicle, characterized in that, The heavy-duty 6×6 off-road vehicle four-speed hub electric drive system includes: hub motor (①) and planetary transmission (②); The hub motor (①) includes: hub motor stator (8) and hub motor rotor (9); The planetary transmission (②) includes: a transmission component assembly, a planetary gear set assembly, a brake assembly, and a one-way clutch assembly; The transmission component assembly includes: a first component (1), a second component (2), a third component (3), a fourth component (4), a fifth component (5), a sixth component (6), and a seventh component (7); The planetary array assembly includes: a first planetary array PGS1, a second planetary array PGS2, and a third planetary array PGS3; The brake assembly includes: a first brake B1 and a second brake B2; The one-way clutch assembly includes: a first one-way clutch C1 and a second one-way clutch C2; The hub motor rotor (9) is connected to the first component (1); The hub motor stator (8) is connected to the seventh component (7); The first planetary gear set PGS1 includes a first sun gear S1, a first planet carrier CA1 and a first gear ring R1, which are connected to the seventh component (7), the first component (1) and the fifth component (5) respectively; The second planetary gear set PGS2 includes a second sun gear S2, a second planet carrier CA2, and a second gear ring R2, which are connected to the fifth component (5), the sixth component (6), and the fourth component (4), respectively. The third planetary gear set PGS3 includes a third sun gear S3, a third planet carrier CA3, and a third gear ring R3, which are connected to the sixth component (6), the second component (2), and the third component (3), respectively. The first brake B1 is used to brake the third component (3); The second brake B2 is used to brake the fourth component (4); The first one-way clutch C1 is used to connect the fourth component (4) and the second component (2); The second one-way clutch C2 is used to connect the second component (2) and the sixth component (6); When the first brake B1 and the second brake B2 are engaged, the third component (3) and the fourth component (4) brake to achieve first gear; When the first one-way clutch C1 and the first brake B1 are engaged, the fourth component (4) and the second component (2) are connected and rotate as a whole, and the third component (3) brakes to achieve second gear; When the second one-way clutch C2 and the second brake B2 are engaged, the second component (2) and the sixth component (6) are connected and rotate as a whole, and the fourth component (4) brakes, thus achieving three gears; When the first one-way clutch C1 and the second one-way clutch C2 are engaged, the fourth component (4) and the second component (2) are connected and rotate as a whole, and the second component (2) and the sixth component (6) are connected and rotate as a whole, thus achieving four gears; The hub motor (①) is a permanent magnet synchronous internal rotor motor; The system uses a hub motor matched with a transmission drive, which can achieve four forward gears; The system requires a forward gear ratio range of at least 6.0.
Citation Information
Patent Citations
Compact-layout two-gear coaxial electric drive axle
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Vehicle three-gear variable-speed hub driving system
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