Electric multi-gear speed change system, electric drive assembly and vehicle chassis

Abstract

The invention belongs to the technical field of automobile power transmission systems, and particularly relates to an electric multi-gear speed change system, an electric drive assembly and a vehicle chassis, two two-gear speed reduction systems are combined to form four-gear speed change power output, the front end is a high-speed speed reduction part, one-stage speed reduction design is adopted, and the rear end is a low-speed speed change part. Two-stage speed reduction design is adopted, power is output through three-stage speed reduction and speed change, the number of gear pairs is reduced, the weight and the size of a speed reduction system can be reduced, the input end can keep running at a high rotating speed, the energy efficiency is higher, and therefore the weight and the size of the electric drive assembly are smaller, and a high-speed small-torque motor with the smaller weight and the smaller size can be adopted. According to the electric drive assembly, the use amount of rare earth permanent magnet materials is reduced, the space occupied by installation of a vehicle chassis can be reduced through the electric drive assembly smaller in weight and size, more batteries can be installed on the chassis body, meanwhile, the energy efficiency of the electric drive assembly is higher, and the endurance mileage can be further increased.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile power transmission systems, and in particular relates to an electric multi-gear speed change system, an electric drive assembly and a vehicle chassis. Background Art

[0002] With the development of new energy vehicles, the trend of new energy for medium and heavy trucks is becoming increasingly obvious. Through product and technological innovation, the weight, volume and cost of new energy vehicle power system products can be effectively reduced, and the amount of permanent magnetic materials used in new energy power system products can be reduced, thereby better promoting the sustainable development of new energy vehicles.

[0003] To reduce the weight, volume and cost of new energy vehicle power systems, current common research directions include:

[0004] High-speed motor: By increasing the speed of the motor, the motor torque can be effectively reduced while ensuring the same power output capacity, thereby effectively reducing the material usage of the motor permanent magnet system and achieving lightweight and low-cost products. At the same time, a high-speed, low-torque gearbox suitable for the motor is developed to effectively reduce the weight, volume and cost of the electric drive system;

[0005] Electromechanical integration: Based on the motor, gearbox and motor controller, it effectively reduces the intermediate connection links and reduces the overall weight and cost;

[0006] Oil cooling: The motor adopts oil cooling to effectively improve the heat dissipation capacity of the motor, improve the motor output capacity, and effectively reduce the weight and volume of the motor product;

[0007] Flat wire motor: By adopting flat wire motor, the slot filling rate of motor stator is improved, and the contact area between motor copper wire winding and motor stator is increased, so as to achieve higher performance and heat dissipation capacity.

[0008] At present, medium and heavy trucks generally use motor + AMT gearbox as a pure electric power transmission system, which effectively improves the output torque of the motor through the gearbox to adapt to different working conditions. However, the motors used are generally low-speed and high-torque (peak speed 3500RPM, peak torque 2500Nm) motors, and the corresponding gearboxes used are low-speed and high-torque gearboxes, which often use a double intermediate shaft structure, making the system heavy, large, and high in energy consumption. The space occupied is also relatively large, which makes the space for installing batteries small and limits the vehicle's mileage. In addition, low-speed and high-torque motors are large in size and require more rare earth permanent magnet materials, which also causes high product costs. Summary of the invention

[0009] The present invention provides an electric multi-speed transmission system, an electric drive assembly and a vehicle chassis, which adopt a high-speed, low-torque motor and realize a three-level four-speed transmission function through two two-speed reduction systems, realize high-speed rotation of the motor, and effectively reduce the weight and volume of the transmission system.

[0010] Based on the above purpose, the present invention provides an electric multi-gear transmission system, comprising:

[0011] At least one rotating shaft 1, the rotating shaft 1 being a power input end, a driving gear 1 and a driving gear 2 being fixedly mounted on the rotating shaft 1, and the driving gear 1 and the driving gear 2 being meshed with a driven gear 1 and a driven gear 2 respectively;

[0012] at least one rotating shaft 2, on which a driven gear 3 and a driving gear 3 are fixedly mounted, and the driven gear 3 and the driving gear 3 are respectively meshed with a driving gear 4 and a driven gear 4; and

[0013] An intermediate shaft, on which a transmission shift member 1 and a transmission shift member 2 are provided, wherein the transmission shift member 1 can be selectively engaged with the driven gear 1 or the driven gear 2 to form a two-speed reduction system 1; the transmission shift member 2 can be selectively engaged with the driving gear 4 or the driven gear 4 to form a two-speed reduction system 2, and the driven gear 4 is used to connect the power output end.

[0014] Optionally, the number of the rotating shafts 1 is two, and each rotating shaft 1 is used to connect to a motor.

[0015] Optionally, the intermediate shaft passes through the shaft holes of the driven gear 1, the driven gear 2 and the driving gear 4 and is clearance-fitted, and an output shaft is rotatably provided at one end of the intermediate shaft, and the output shaft is fixedly connected to the driven gear 4.

[0016] Optionally, a bearing is fixedly mounted on the end of the intermediate shaft, and the outer ring of the bearing is coaxially and rigidly connected to the output shaft.

[0017] Optionally, the number of the second rotating shafts is two.

[0018] Optionally, the transmission shift member 1 and the transmission shift member 2 are connected to the intermediate shaft via splines and can selectively move along the axial direction of the intermediate shaft.

[0019] Optionally, the transmission shift member 1 and the transmission shift member 2 are coupling sleeves or clutches.

[0020] Optionally, the transmission ratio of the driving gear 1 to the driven gear 1 is 1-4, the transmission ratio of the driving gear 2 to the driven gear 2 is 1-4, the transmission ratio of the driving gear 4 to the driven gear 3 is 1-2, and the transmission ratio of the driving gear 3 to the driven gear 4 is 1-2.

[0021] The present invention provides an electric drive assembly, comprising the electric multi-speed transmission system as described above, a drive motor drivingly connected to the input end of the electric multi-speed transmission system, and an output flange fixedly connected to the power output end of the electric multi-speed transmission system.

[0022] Optionally, the peak speed of the drive motor is ≥10000RPM, and the peak torque is ≤500Nm.

[0023] The present invention provides a vehicle chassis, comprising the electric drive assembly and a chassis body as described above, wherein the electric drive assembly is fixedly mounted on the chassis body.

[0024] The beneficial effects of the present invention are as follows: the electric multi-speed transmission system provided by the present invention has a two-speed reduction system 1 that adopts a two-speed one-stage high-speed reduction speed change. Specifically, the driving gear 1 is meshed with the driven gear 1, and the driving gear 2 is meshed with the driven gear 2 to form two reduction gear pairs. The transmission shift member 1 on the intermediate shaft selectively engages with the driven gear 1 or the driven gear 2 during operation to reduce the high-speed power at the power input end and increase the torque, and the output is a low-speed and high-torque. The power is transmitted to the two-speed reduction system 2 at the rear end, and the transmission shift member 2 selectively engages with the driving gear 4 to achieve two-stage reduction. Therefore, the transmission system realizes the output of power through three-stage reduction speed change through four pairs of gears, reduces the number of gear pairs, and is beneficial to reducing the weight and volume of the reduction system; and the two-speed reduction system 1 adopts a high-speed and low-torque design, which is lighter and smaller than the existing low-speed and high-torque design, and the motor as the power input source can be kept running at a high speed, and the energy efficiency is also higher.

[0025] The electric drive assembly provided by the present invention can be equipped with a small high-speed, low-torque motor through an electric multi-speed transmission system with smaller volume and weight and higher deceleration efficiency, so that the weight and volume of the electric drive assembly are smaller, the drive motor can rotate at high speed, and while ensuring the output power, the amount of rare earth permanent magnet material used is reduced. The drive motor can maintain a high rotation speed for a long time, thereby improving the energy efficiency of the electric drive assembly.

[0026] The vehicle chassis provided by the present invention can reduce the space occupied by the installation through the electric drive assembly with smaller weight and volume, so that more batteries can be installed on the chassis body. At the same time, the energy efficiency of the electric drive assembly is higher, which can further improve the cruising range. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of a multi-speed transmission system of an electric drive assembly provided in an embodiment of the present invention;

[0028] Figure 2The three-stage speed change principle of the multi-gear speed change system provided by the embodiment of the present invention Figure 1 ;

[0029] Figure 3 The three-stage speed change principle of the multi-gear speed change system provided by the embodiment of the present invention Figure 2 ;

[0030] Figure 4 The first-stage speed change principle of the multi-gear speed change system provided by the embodiment of the present invention Figure 1 ;

[0031] Figure 5 The first-stage speed change principle of the multi-gear speed change system provided by the embodiment of the present invention Figure 2 .

[0032] In the figure: 1, two-speed reduction system one; 2, two-speed reduction system two; 10, rotating shaft one; 11, driving gear one; 12, driving gear two; 13, driven gear one; 14, driven gear two; 20, intermediate shaft; 21, transmission shift piece one; 22, transmission shift piece two; 23, bearing; 30, rotating shaft two; 31, driven gear three; 32, driving gear three; 33, driving gear four; 34, driven gear four; 40, output shaft; 50, drive motor; 60, output flange. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0034] like Figure 1-5 As shown, the present invention provides an electric multi-gear transmission system, comprising: at least one rotating shaft 10, at least one rotating shaft 2 30 and an intermediate shaft 20, wherein the rotating shaft 10 is a power input end, a driving gear 11 and a driving gear 2 12 are fixedly mounted on the rotating shaft 10, and the driving gear 11 and the driving gear 2 12 are respectively meshed with a driven gear 13 and a driven gear 2 14; a driven gear 3 31 and a driving gear 3 32 are fixedly mounted on the rotating shaft 2 30, and the driven gear 13 and the driven gear 13 are respectively meshed with the driven gear 13 and the driven gear 13. The gear three 31 and the driving gear three 32 are respectively meshed with the driving gear four 33 and the driven gear four 34; the intermediate shaft 20 is provided with a transmission shift member 1 21 and a transmission shift member 2 22, the transmission shift member 1 21 can selectively engage with the driven gear one 13 or the driven gear two 14 to form a two-speed reduction system one 1; the transmission shift member two 22 can selectively engage with the driving gear four 33 or the driven gear four 34 to form a two-speed reduction system two 2, and the driven gear four 34 is used to connect the power output end.

[0035] Compared with the prior art, the electric multi-speed transmission system provided by the embodiment of the present invention has a two-speed reduction system 1 that adopts a two-speed one-stage high-speed reduction speed change. Specifically, the driving gear 11 is meshed with the driven gear 13, and the driving gear 2 12 is meshed with the driven gear 2 14 to form two reduction gear pairs. The transmission shift member 1 21 on the intermediate shaft 20 selectively engages with the driven gear 1 13 or the driven gear 2 14 during operation to reduce the high-speed power at the power input end and increase the torque, and outputs a low-speed and high-torque power. The power is transmitted to the two-speed reduction system 2 at the rear end, and the transmission shift member 2 22 selectively engages with the driving gear 4 33 to achieve two-stage reduction. Therefore, the transmission system realizes the output of power through three-stage reduction speed change through four pairs of gears, reduces the number of gear pairs, and is conducive to reducing the weight and volume of the reduction system; in addition, the two-speed reduction system 1 adopts a high-speed and low-torque design, which is lighter and smaller than the existing low-speed and high-torque design, and the motor as the power input source can be kept running at a high speed, and the energy efficiency is also higher.

[0036] In this embodiment, when the weight and volume of the transmission system are smaller, the number of rotating shafts 10 can be two, so that the transmission system has two power input ends, which can drive and connect two motors, and realize dual-motor drive by coupling the two motors, which is beneficial to improving the torque at the output end and is more suitable for the drive systems of medium and heavy trucks.

[0037] Specifically, two rotating shafts 10 are arranged side by side, and the driving gear 11 and the driving gear 2 12 installed on the two transmission shafts 1 are respectively meshed with the driven gear 1 13 and the driven gear 2 14. The power input from the two power input ends passes through the driving gear 1 11 and the driven gear 1 13, or through the driving gear 2 12 and the driven gear 2 14, and is transmitted to the intermediate shaft 20 through the transmission shift member 1 21, and then transmitted to the rear end two-speed reduction system 2 2. Among them, the two rotating shafts 10 and the intermediate shaft 20 can be arranged in a plane form or in a triangle form.

[0038] Among them, the driven gear 1 13 and the driven gear 2 14 are both tower-type gears with a large gear and a small gear. The transmission shift member 1 21 is located between the driven gear 1 and the driven gear 2 14, connected to the intermediate shaft 20 through a spline, and can selectively move along the axial direction of the intermediate shaft 20, so that the transmission shift member 1 21 engages with the small gear of the driven gear 1 13, or engages with the small gear of the driven gear 2 14, to achieve a one-stage two-speed shift.

[0039] In this embodiment, the intermediate shaft 20 passes through the shaft holes of the driven gear 13, the driven gear 2, 14 and the driving gear 4, 33 and is clearance-fitted. The intermediate shaft 20 is arranged to rotate with a fixed axis. An output shaft 40 is rotatably arranged at one end of the intermediate shaft 20, and the output shaft 40 is fixedly connected to the driven gear 4, 34. Specifically, one end of the intermediate shaft 20 away from the two-speed reduction system 1 is located between the driving gear 4, 33 and the driven gear 4, 34. The output shaft 40 is interference-fitted with the shaft hole of the driven gear. The intermediate shaft 20 and the output shaft 40 can rotate at a certain speed respectively, so that the rotation centers of the intermediate shaft 20 and the output shaft 40 are consistent, which is beneficial to the stability of power transmission.

[0040] Among them, the driving gear four 33 and the driven gear four 34 are both tower-shaped gears with a large gear and a small gear. The transmission shift member 22 is located between the driving gear four 33 and the driven gear four 34, connected to the intermediate shaft 20 through a spline, and can selectively move along the axial direction of the intermediate shaft 20, so that the transmission shift member 22 engages with the small gear of the driving gear four 33, or engages with the small gear of the driven gear four 34, to achieve a two-stage two-speed shift.

[0041] In one embodiment, a bearing 23 is fixedly installed at the end of the intermediate shaft 20, and the outer ring of the bearing 23 is coaxially rigidly connected to the output shaft 40. Specifically, the bearing 23 is fixedly installed, the intermediate shaft 20 and the inner ring of the bearing 23 are interference fit, and the output shaft 40 is fixedly connected to the outer ring of the bearing 23 through a sleeve, so that the intermediate shaft 20 and the bearing 23 are rotatably connected; in other embodiments, the intermediate shaft 20 and the bearing 23 can also be connected at the ends of the two bearings 23 to realize that the intermediate shaft 20 and the bearing 23 can each rotate at a certain speed.

[0042] In this embodiment, there are two rotating shafts 2 30. The driven gear 3 31 and the driving gear 3 32 provided on the two rotating shafts 2 30 are respectively meshed with the driving gear 4 33 and the driven gear 4 34, so that the power of the intermediate shaft 20 is divided into two groups and transmitted to the output shaft 40, so that the carrying capacity of the two-speed reduction system 2 2 can be improved, and the two-speed reduction system 2 2 can adopt a low-speed and high-torque design, which is also conducive to improving the reduction ratio.

[0043] The two second rotating shafts 30 and the intermediate shaft 20 may be arranged in a plane or in a triangle, and may be arranged in the same manner as the first rotating shaft 10, or may be different.

[0044] Optionally, the transmission shift member 1 21 and the transmission shift member 2 22 are a coupling sleeve or a clutch, etc.

[0045] In this embodiment, the transmission ratio of the driving gear 11 and the driven gear 1 13 is 1-4, the transmission ratio of the driving gear 2 12 and the driven gear 2 14 is 1-4, the transmission ratio of the driving gear 4 33 and the driven gear 3 31 is 1-2, and the transmission ratio of the driving gear 3 32 and the driven gear 4 34 is 1-2, so that the motor power is output through three-stage speed reduction, the maximum reduction ratio is ≥40, and the reduction efficiency is high.

[0046] It should be noted that the number of teeth of the driving gear 1 11 is different from that of the driving gear 2 12, the number of teeth of the driven gear 1 13 and the driven gear 2 14 are selected according to the driving gear 1 11 and the driving gear 2 12 respectively, the number of teeth of the driving gear 3 32 and the driven gear 3 31 is different, and the number of teeth of the driving gear 4 33 and the driven gear 4 34 rotate according to the driven gear 3 31 and the driving gear 3 32 respectively.

[0047] When using, please refer to Figure 2 , the arrow in the figure indicates the direction of power transmission, the same below, when the transmission shift member 21 is engaged with the driven gear 1 13, and the transmission shift member 22 is engaged with the driving gear 4 33, the power at the input end passes through the driving gear 1 11 and the driven gear 1 13, performs a first-stage deceleration, is transmitted to the driving gear 4 33 and the driven gear 3 31, performs a second-stage deceleration, passes through the rotating shaft 2 30 to the driving gear 3 32 and the driven gear 4 34, performs a third-stage deceleration, and outputs the power through the output shaft 40.

[0048] See also Figure 3 When the transmission shift member 1 21 is engaged with the driven gear 2 14, and the transmission shift member 22 is engaged with the driving gear 4 33, the power at the input end passes through the driving gear 2 12 and the driven gear 2 14, performs a first-stage deceleration, is transmitted to the driving gear 4 33 and the driven gear 3 31, performs a second-stage deceleration, passes through the rotating shaft 2 30 to the driving gear 3 32 and the driven gear 4 34, performs a third-stage deceleration, and outputs the power through the output shaft 40.

[0049] See also Figure 4 When the transmission shift member 21 is engaged with the driven gear 13, and the transmission shift member 22 is engaged with the driven gear 4 34, the power at the input end is reduced in one stage through the driving gear 11 and the driven gear 1 13, and is transmitted to the driven gear 4 34, and the power is output through the output shaft 40.

[0050] See also Figure 5 When the transmission shift member 1 21 is engaged with the driven gear 2 14, and the transmission shift member 2 22 is engaged with the driven gear 4 34, the power at the input end is reduced in one stage through the driving gear 2 12 and the driven gear 2 14, and is transmitted to the driven gear 4 34, and the power is output through the output shaft 40.

[0051] The present invention provides an electric drive assembly, comprising the electric multi-speed transmission system as described above, a drive motor 50 drivingly connected to the input end of the electric multi-speed transmission system, and an output flange 60 fixedly connected to the power output end of the electric multi-speed transmission system. The electric multi-speed transmission system with smaller volume and weight and higher deceleration efficiency can be equipped with a small-volume high-speed and low-torque motor, so that the weight and volume of the electric drive assembly are smaller, so that the drive motor 50 can rotate at a high speed, while ensuring the output power, reducing the amount of rare earth permanent magnet material, and the drive motor 50 can maintain a high speed for a long time, thereby improving the energy efficiency of the electric drive assembly.

[0052] Optionally, the peak speed of the driving motor 50 is ≥10000 RPM, and the peak torque is ≤500 Nm.

[0053] The present invention provides a vehicle chassis, comprising the above-mentioned electric drive assembly and a chassis body, wherein the electric drive assembly is fixedly mounted on the chassis body. The electric drive assembly with a smaller weight and volume can reduce the space occupied by the installation, so that more batteries can be installed on the chassis body. At the same time, the electric drive assembly has a higher energy efficiency, which can further improve the cruising range.

[0054] A person skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0055] One or more embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the present application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of the present application should be included in the protection scope of the present application.

Claims

1. An electric multi-speed transmission system, characterized in that: include: At least one rotating shaft (10), the rotating shaft (10) being a power input end, a driving gear (11) and a driving gear (12) being fixedly mounted on the rotating shaft (10), the driving gear (11) and the driving gear (12) being respectively meshed with a driven gear (13) and a driven gear (14); At least one rotating shaft 2 (30), on which a driven gear 3 (31) and a driving gear 3 (32) are fixedly mounted, and the driven gear 3 (31) and the driving gear 3 (32) are respectively meshed with a driving gear 4 (33) and a driven gear 4 (34); and An intermediate shaft (20) is provided with a transmission shift member 1 (21) and a transmission shift member 2 (22), wherein the transmission shift member 1 (21) can be selectively engaged with a driven gear 1 (13) or a driven gear 2 (14) to form a two-speed reduction system 1 (1); the transmission shift member 2 (22) can be selectively engaged with a driving gear 4 (33) or a driven gear 4 (34) to form a two-speed reduction system 2 (2), wherein the driven gear 4 (34) is used to connect to a power output end.

2. The electric multi-speed transmission system according to claim 1, characterized in that: The number of the rotating shafts one (10) is two, and each rotating shaft one (10) is used to connect to a motor.

3. The electric multi-speed transmission system according to claim 1, characterized in that: The intermediate shaft (20) passes through the shaft holes of the driven gear 1 (13), the driven gear 2 (14) and the driving gear 4 (33) and is clearance-fitted therewith. An output shaft (40) is rotatably provided at one end of the intermediate shaft (20), and the output shaft (40) is fixedly connected to the driven gear 4 (34).

4. The electric multi-speed transmission system according to claim 3, characterized in that: A bearing (23) is fixedly mounted on the end of the intermediate shaft (20), and the outer ring of the bearing (23) is coaxially and rigidly connected to the output shaft (40).

5. The electric multi-speed transmission system according to claim 1, characterized in that: The number of the second rotating shaft (30) is two.

6. The electric multi-speed transmission system according to claim 1, characterized in that: The transmission shift member 1 (21) and the transmission shift member 2 (22) are connected to the intermediate shaft (20) via splines and can selectively move along the axial direction of the intermediate shaft (20).

7. The electric multi-speed transmission system according to claim 6, characterized in that: The transmission shifting member 1 (21) and the transmission shifting member 2 (22) are coupling sleeves or clutches.

8. The electric multi-speed transmission system according to any one of claims 1 to 7, characterized in that: The transmission ratio between the driving gear 1 (11) and the driven gear 1 (13) is 1-4, the transmission ratio between the driving gear 2 (12) and the driven gear 2 (14) is 1-4, the transmission ratio between the driving gear 4 (33) and the driven gear 3 (31) is 1-2, and the transmission ratio between the driving gear 3 (32) and the driven gear 4 (34) is 1-2.

9. An electric drive assembly, characterized in that: It comprises the electric multi-speed transmission system as claimed in any one of claims 1 to 7, a driving motor (50) drivingly connected to the input end of the electric multi-speed transmission system, and an output flange (60) fixedly connected to the power output end of the electric multi-speed transmission system.

10. A vehicle chassis, characterized in that: It comprises the electric drive assembly as claimed in claim 9 and a chassis body, wherein the electric drive assembly is fixedly mounted on the chassis body.

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