A multi-main reducer dual-motor coupling drive system

Abstract

The present invention discloses a multi-main reducer dual-motor coupling drive system, which is composed of a main drive motor, a main motor driving gear, a speed coupling driving gear, a speed coupling device, an auxiliary motor driving gear, an auxiliary drive motor, an auxiliary motor driven gear, a differential, a speed coupling driven gear, a main motor driven gear, and an electromagnetic clutch. By changing the different opening and closing states of the electromagnetic clutch and the different working states of the two drive motors, four driving modes can be realized, namely, dual-motor speed coupling drive, dual-motor torque coupling drive, main motor single drive, and auxiliary motor single drive. The high-efficiency range of the two drive motors can be more fully utilized to match different driving conditions, improve the economy of the whole vehicle, and increase the cruising range. At the same time, a multi-main reduction design is adopted, and the power of different drive modes is directly output to the differential, with fewer transmission links and high transmission efficiency; the differential housing is directly used for torque coupling, the number of shaft systems is reduced, and the structure is more compact.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy vehicle powertrain, and specifically relates to a dual-motor coupling drive system for a pure electric vehicle. Background Art

[0002] At present, the traditional automobile industry has begun to transform to electrification under the dual pressure of energy and ecology. The main disadvantage of pure electric vehicles in daily use is insufficient endurance, which leads to low reliability in long-distance driving applications. Therefore, an important part of developing pure electric vehicles and improving their user experience is to enhance the endurance of pure electric vehicles.

[0003] Electric vehicles use a dual-motor coupling drive system, which can decompose a large-capacity motor into two small-capacity motors to drive the car, avoiding the motor load rate being too low when the car is in a low-load condition; and can achieve the complementarity of the mechanical characteristics of the two motors through the coupling device, facing the various working conditions of the car, and can make the two motors operate in their own high-efficiency range as much as possible. Therefore, no matter what form of energy supply (battery or fuel cell) the electric vehicle adopts, compared with vehicles driven by a single motor or multiple motors independently, vehicles equipped with a dual-motor coupling drive system are expected to achieve more efficient driving, thereby achieving energy saving and increasing the cruising range. Many patents have been published in related fields, but most of them have complex structures due to the pursuit of comprehensive functions, which in turn causes the transmission device to be larger in size, which is not conducive to the layout of the entire vehicle. At the same time, the large number of transmission links also causes some energy loss. The relevant patents mainly achieve power coupling in two ways. One is to use a floating stator, such as the utility model CN207510200 U. This configuration has a simple structure, but because the floating stator requires collector rings and brushes for power supply, the system reliability is reduced, the maintenance cost is increased, and the stator has a large moment of inertia. The other is to use a planetary gear row with a fixed-axis gear train to achieve different power coupling methods. This structure works stably, but the power coupling device will occupy a larger space, and more transmission links will produce additional energy losses. Summary of the invention

[0004] The purpose of the present invention is to increase the cruising range of a pure electric vehicle by improving the efficiency of the drive system, while minimizing the size of the power coupling device to leave more space for the power battery pack.

[0005] The object of the present invention is achieved through the following technical solutions: a multi-main reducer dual-motor coupling drive system, including a main drive motor, a main motor driving gear, a first electromagnetic clutch, a speed coupling driving gear, a speed coupling device, a second electromagnetic clutch, an auxiliary motor driving gear, an auxiliary drive motor, an auxiliary motor driven gear, a third electromagnetic clutch, a differential, a speed coupling driven gear, a fourth electromagnetic clutch, and a main motor driven gear. The main motor driving gear and the main motor driven gear, the speed coupling driving gear and the speed coupling driven gear, the auxiliary motor driving gear and the auxiliary motor driven gear constitute three sets of main reducers; the main drive motor and the auxiliary drive motor are on opposite sides. Coaxial arrangement; the output shaft of the main drive motor directly drives the main motor driving gear, the main motor driven gear is suspended on the half shaft through a hollow shaft, and is connected to the differential housing through a fourth electromagnetic clutch; the output shaft of the auxiliary drive motor directly drives the auxiliary motor driving gear, the auxiliary motor driven gear is suspended on the half shaft through a hollow shaft, and is connected to the differential housing through a third electromagnetic clutch; the shafts of the main motor driving gear and the auxiliary motor driving gear are respectively connected to the two sun gears of the speed coupling device through the first electromagnetic clutch and the second electromagnetic clutch; the speed coupling driving gear is installed on the housing of the speed coupling device, and the speed coupling device driven gear is installed on the housing of the differential.

[0006] Furthermore, splines are processed on both sides of the clutch housing, and the splines respectively match with the splines on the driven parts of the fourth electromagnetic clutch and the third electromagnetic clutch.

[0007] Furthermore, the speed coupling device adopts a straight bevel gear planetary gear system structure.

[0008] The present invention has the following beneficial effects: (1) Compared with the existing dual-motor coupling drive system, the present configuration simplifies the shaft system structure, the power coupling device is more compact, and its radial size is small, which is conducive to the layout of the interior space. (2) While maintaining a compact structure, the present invention can realize multiple driving modes. For frequent start-stop and slow driving congested road conditions, the auxiliary motor can be driven alone to reduce losses. For extreme conditions of climbing and high speed, the torque coupling mode and the speed coupling mode are used to maintain the efficient driving of the two motors. The main motor single drive mode covers the power requirements of daily driving on urban roads. There are many driving modes and flexible control schemes, which can effectively utilize the high-efficiency range of the motor. (3) The present invention changes the single main reducer design of the traditional drive axle. The power of the speed coupling device and the torque coupling device are directly output to the differential housing. There are fewer transmission links and a shorter transmission route. Compared with other dual-motor coupling configurations, it is more conducive to improving the transmission efficiency of the drive system. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of the structure of the present invention.

[0010] Figure 2 Schematic diagram of energy flow in speed-coupled drive mode.

[0011] Figure 3 Schematic diagram of energy flow in torque coupling drive mode.

[0012] Figure 4 Schematic diagram of energy flow for the main motor single drive mode.

[0013] Figure 5 Schematic diagram of energy flow in auxiliary motor single drive mode.

[0014] Explanation of the accompanying drawings: 1. main drive motor; 2. main motor driving gear; 3. first electromagnetic clutch; 4. speed coupling driving gear; 5. speed coupling device; 6. second electromagnetic clutch; 7. auxiliary motor driving gear; 8. auxiliary drive motor; 9. auxiliary motor driven gear; 10. third electromagnetic clutch; 11. differential; 12. speed coupling driven gear; 13. fourth electromagnetic clutch; 14. main motor driven gear. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the preferred embodiments are only for illustrating the present invention and are not intended to limit the protection scope of the present invention.

[0016] A multi-main reducer dual-motor coupling drive system comprises a main drive motor 1, a main motor driving gear 2, a first electromagnetic clutch 3, a speed coupling driving gear 4, a speed coupling device 5, a second electromagnetic clutch 6, an auxiliary motor driving gear 7, an auxiliary drive motor 8, an auxiliary motor driven gear 9, a third electromagnetic clutch 10, a differential 11, a speed coupling driven gear 12, a fourth electromagnetic clutch 13, and a main motor driven gear 14. The main motor driving gear 2 and the main motor driven gear 14, the speed coupling driving gear 4 and the speed coupling driven gear 12, the auxiliary motor driving gear 7 and the auxiliary motor driven gear 9 constitute three sets of main reducers; the main drive motor 1 and the auxiliary drive motor 8 are coaxially arranged on opposite sides; The output shaft of the driving motor 1 directly drives the main motor driving gear 2, and the main motor driven gear 14 is suspended on the half shaft through a hollow shaft, and is connected to the differential 11 housing through the fourth electromagnetic clutch 13; the output shaft of the auxiliary driving motor 8 directly drives the auxiliary motor driving gear 7, and the auxiliary motor driven gear 9 is suspended on the half shaft through a hollow shaft, and is connected to the differential housing through the third electromagnetic clutch 10; the shafts of the main motor driving gear 2 and the auxiliary motor driving gear 7 are respectively connected to the two sun gears of the speed coupling device through the first electromagnetic clutch 3 and the second electromagnetic clutch 6; the speed coupling driving gear 4 is installed on the housing of the speed coupling device 5, and the speed coupling device driven gear 12 is installed on the housing of the differential 11.

[0017] In this embodiment, splines are processed on both sides of the housing of the clutch 11, and the splines respectively cooperate with the splines on the driven parts of the fourth electromagnetic clutch 13 and the third electromagnetic clutch 10, thereby realizing torque coupling in the differential housing.

[0018] In this embodiment, the speed coupling device 5 adopts a straight bevel gear planetary gear system structure to further reduce the radial size of the power coupling device.

[0019] In the present invention, the main drive motor 1 and the auxiliary drive motor 8 can be replaced with other forms of power sources (such as internal combustion engines), that is, the power coupling device can be adapted to different types of power source combinations.

[0020] The working principle of the multi-main reducer dual-motor coupling drive system proposed in the present invention is as follows:

[0021] The controller realizes the conversion of different working modes by controlling the different opening and closing states of the four electromagnetic clutches and the different working states of the two drive motors. Table 1 lists the driving mode relationships corresponding to different clutch opening and closing states. In Table 1, "●" represents clutch engagement; "○" represents clutch disconnection; "M" represents the motor working in the motor state; "G" represents the motor working in the generator state; "C" represents the motor off.

[0022] Table 1 Correspondence between actuator status and drive mode

[0023]

[0024] In the speed coupling driving mode, the first electromagnetic clutch 3 and the second electromagnetic clutch 6 are engaged, and both drive motors are in the motor working state. The power of the main drive motor 1 and the auxiliary drive motor 8 is transmitted to the sun gear of the speed coupling device 5 through the first electromagnetic clutch 3 and the second electromagnetic clutch 6. The sun gear drives the speed coupling active gear 4 outside the speed coupling device housing through the planetary gear. The speed coupling active gear 4 drives the speed coupling driven gear 12 on the differential housing. The differential 11 distributes the power to the two drive half-axles driving wheels. The energy flow route in this mode can be referred to Figure 2 The speed coupling working mode is suitable for high-speed cruising conditions of automobiles.

[0025] In the torque coupling mode, the fourth electromagnetic clutch 13 and the third electromagnetic clutch 10 are engaged, and both drive motors work in the motor state. The power of the main drive motor 1 is transmitted to the housing of the differential 5 via the main motor driving gear 2, the main motor driven gear 14, and the fourth electromagnetic clutch 13. The power of the auxiliary motor 8 is transmitted to the housing of the differential 5 via the auxiliary motor driving gear 7, the auxiliary motor driven gear 9, and the third electromagnetic clutch 10. After the power of the two motors is directly coupled in the differential housing, the differential 5 distributes the power to the two drive half-axles driving wheels. The energy flow route in this mode can be referred to Figure 3 The torque coupling working mode is suitable for low-speed and high-torque conditions such as vehicle climbing.

[0026] In the main motor single drive mode, only the fourth electromagnetic clutch 13 is engaged, the main drive motor works in the motor state, and the auxiliary drive motor is turned off. The power of the main drive motor 1 is transmitted to the housing of the differential 5 via the main motor driving gear 2, the main motor driven gear 14, and the fourth electromagnetic clutch 13. The differential 5 distributes the power to the two driving half-axles driving wheels. The energy flow route in this mode can be referred to Figure 4 The main motor single drive working mode is suitable for vehicle starting and medium-speed cruising conditions.

[0027] In the torque coupling mode, the fourth electromagnetic clutch 13 and the third electromagnetic clutch 10 are engaged, and both drive motors work in the motor state. The power of the main drive motor 1 is transmitted to the housing of the differential 5 via the main motor driving gear 2, the main motor driven gear 14, and the fourth electromagnetic clutch 13. The power of the auxiliary motor 8 is transmitted to the housing of the differential 5 via the auxiliary motor driving gear 7, the auxiliary motor driven gear 9, and the third electromagnetic clutch 10. After the power of the two motors is directly coupled in the differential housing, the differential 5 distributes the power to the two drive half-axles driving wheels. The energy flow route in this mode can be referred to Figure 3 The torque coupling working mode is suitable for low-speed and high-torque conditions such as vehicle climbing.

[0028] Corresponding to the above four driving working modes, when the working motor switches from the motor state to the generator state, the braking energy recovery of the corresponding mode can be realized.

[0029] The above is an exemplary description of the present invention in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various modifications are made using the method concept and technical solution of the present invention, or are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A multi-main reducer dual-motor coupling drive system, comprising a main drive motor (1), a main motor driving gear (2), a first electromagnetic clutch (3), a speed coupling driving gear (4), a speed coupling device (5), a second electromagnetic clutch (6), an auxiliary motor driving gear (7), an auxiliary drive motor (8), an auxiliary motor driven gear (9), a third electromagnetic clutch (10), a differential (11), a speed coupling driven gear (12), a fourth electromagnetic clutch (13), and a main motor driven gear (14), characterized in that: The main motor driving gear (2) and the main motor driven gear (14), the speed coupling driving gear (4) and the speed coupling driven gear (12), the auxiliary motor driving gear (7) and the auxiliary motor driven gear (9) form three sets of main reducers; the main drive motor (1) and the auxiliary drive motor (8) are coaxially arranged on different sides; the output shaft of the main drive motor (1) directly drives the main motor driving gear (2), the main motor driven gear (14) is suspended on the half shaft through a hollow shaft, and is connected to the differential (11) housing through the fourth electromagnetic clutch (13); the output shaft of the auxiliary drive motor (8) directly drives the auxiliary motor driving gear (7), the auxiliary motor The driven gear (9) of the main motor is suspended on the half shaft through a hollow shaft and is connected to the differential housing through the third electromagnetic clutch (10); the shafts of the main motor driving gear (2) and the auxiliary motor driving gear (7) are respectively connected to the two sun gears of the speed coupling device through the first electromagnetic clutch (3) and the second electromagnetic clutch (6); the speed coupling driving gear (4) is installed on the housing of the speed coupling device (5), and the speed coupling driven gear (12) is installed on the housing of the differential (11); the controller can realize four-speed automatic transmission by controlling the different opening and closing states of the first electromagnetic clutch, the second electromagnetic clutch, the third electromagnetic clutch and the fourth electromagnetic clutch and the different working states of the main drive motor and the auxiliary drive motor. There are different working modes, namely speed coupling driving mode, torque coupling mode, main motor single driving mode, auxiliary motor single driving mode, among which: in the speed coupling driving mode, the first electromagnetic clutch and the second electromagnetic clutch are engaged, and the two drive motors are in the motor working state; the power of the main drive motor and the auxiliary drive motor is transmitted to the sun gear of the speed coupling device through the first electromagnetic clutch and the second electromagnetic clutch, and the sun gear drives the speed coupling active gear outside the housing of the speed coupling device through the planetary gear, and the speed coupling active gear drives the speed coupling driven gear on the differential housing, and the differential distributes the power to the two drive half-shafts to drive the wheels; in the torque coupling mode, the fourth electromagnetic clutch and the third electromagnetic clutch are engaged, Both drive motors work in the motor state; the power of the main drive motor is transmitted to the differential housing via the main motor driving gear, the main motor driven gear, and the fourth electromagnetic clutch, and the power of the auxiliary motor is transmitted to the differential housing via the auxiliary motor driving gear, the auxiliary motor driven gear, and the third electromagnetic clutch. After the power of the two motors is directly coupled in the differential housing, the differential distributes the power to the two drive half-axles driving wheels; in the main motor single drive mode, only the fourth electromagnetic clutch is engaged, the main drive motor works in the motor state, and the auxiliary drive motor is shut down; the power of the main drive motor is transmitted to the differential housing via the main motor driving gear, the main motor driven gear, and the fourth electromagnetic clutch, and the differential distributes the power to the two drive half-axles driving wheels;In the auxiliary motor single drive mode, only the third electromagnetic clutch is engaged, the main drive motor is shut down, and the auxiliary drive motor works in the motor state; the power of the auxiliary motor is transmitted to the differential housing via the auxiliary motor driving gear, the auxiliary motor driven gear, and the electromagnetic clutch, and the differential distributes the power to the two driving half-axles driving wheels; Both sides of the housing of the differential (11) are processed with splines, and the splines respectively match with the splines on the driven parts of the fourth electromagnetic clutch (13) and the third electromagnetic clutch (10); The speed coupling device (5) adopts a straight bevel gear planetary gear system structure.

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