Control method, controller, and vehicle

Abstract

This invention relates to a vehicle control method, a controller, and a vehicle. The control method includes: upon receiving a locking command, first controlling the wheel-end decouplers of the vehicle's differential to perform a coupling operation, and then controlling the differential lock of the differential to perform a locking operation. According to the vehicle control method of this invention, when the differential lock is locked, the wheel-end decouplers have already been coupled in advance. This avoids the locking failure problem caused by performing the locking operation in a wheel-end uncoupled state, as seen in related technologies, and ensures the normal operation of the differential lock.

Description

Technical Field

[0001] This invention belongs to the field of vehicle powertrain technology, and relates to a vehicle control method, controller, and vehicle. Background Technology

[0002] In related technologies, differentials equipped with electronic differential locks can achieve differential rotation and same-speed rotation of the wheel ends by controlling the opening and closing of the locking mechanism, thus meeting the needs of different vehicle driving conditions. Therefore, preventing differential lock failure is a technical problem that urgently needs to be solved. Summary of the Invention

[0003] This invention provides a vehicle control method, controller, and vehicle to solve the problem of locking failure that occurs when performing locking operations in the prior art when the wheel ends are not coupled.

[0004] To address the aforementioned technical problems, in one aspect, embodiments of the present invention provide a vehicle control method, comprising:

[0005] Upon receiving a locking command, the system first controls the wheel-end decoupling device of the vehicle's differential to perform a coupling operation, and then controls the differential lock of the differential to perform a locking operation.

[0006] Optionally, the step of first controlling the wheel-end decoupling device of the vehicle's differential to perform a coupling operation, and then controlling the differential lock of the differential to perform a locking operation, includes:

[0007] When the vehicle meets the locking enable condition, the differential lock is controlled to perform a locking operation, wherein the locking enable condition includes: the vehicle speed is less than the first target vehicle speed;

[0008] When the vehicle meets the forced coupling condition, the wheel-end decoupler is controlled to perform a coupling operation, wherein the forced coupling condition includes: the vehicle speed is less than the second target vehicle speed;

[0009] Wherein, the first target vehicle speed is less than the second target vehicle speed.

[0010] Optionally, the range of the first target vehicle speed is (0, 5) km / h.

[0011] Optionally, the range of the second target vehicle speed is: [5, 10) km / h.

[0012] Optionally, when the vehicle meets the unlocking enable conditions, the differential lock is allowed to perform an unlocking operation, wherein the unlocking enable conditions include: the vehicle speed is greater than the third target speed, and the third target speed is greater than the second target speed.

[0013] Optionally, the range of the third target vehicle speed is (30, 50) km / h.

[0014] Optionally, the vehicle is a four-wheel drive vehicle, and the differential is the auxiliary drive differential of the four-wheel drive vehicle.

[0015] Optionally, it also includes:

[0016] When the vehicle meets the locking enable conditions, the differential lock is allowed to perform a locking operation. The locking enable conditions include: the vehicle speed is less than the first target vehicle speed, the speed difference between the connecting shafts at both ends of the wheel-end decoupler is less than the first target speed difference, and the output torque of the vehicle is less than the first target torque.

[0017] When the vehicle meets the coupling enable conditions, the wheel-end decoupler is allowed to perform coupling operation. The coupling enable conditions include: the speed difference between the connecting shafts at both ends of the wheel-end decoupler is less than a second target speed difference, and the output torque of the auxiliary drive is less than a first target torque, wherein the second target speed difference is less than the first target speed difference.

[0018] Optionally, the range of the first target speed difference is (30, 100) rpm.

[0019] Optionally, the range of the second target speed difference is (0, 30] rpm.

[0020] Optionally, when the auxiliary drive meets the forced coupling condition, the wheel-end decoupler of the auxiliary drive is controlled to perform a coupling operation, wherein the forced coupling condition includes: the speed of the four-wheel drive vehicle is greater than the fourth target speed, wherein the fourth target speed is greater than the third target speed.

[0021] Optionally, the range of the fourth target vehicle speed is (120, the maximum permissible speed) km / h.

[0022] According to the vehicle control method of this invention, upon receiving a locking command, the wheel-end decouplers of the vehicle's differential are first controlled to perform a coupling operation, and then the differential lock of the differential is controlled to perform a locking operation. In this way, when the differential lock is locked, the wheel-end decouplers have already been coupled in advance. This avoids the locking failure problem caused by performing the locking operation in a wheel-end uncoupled state, as seen in related technologies, and ensures the normal operation of the differential lock.

[0023] On the other hand, embodiments of the present invention provide a controller that operates according to the control method described above.

[0024] In another aspect, embodiments of the present invention provide a vehicle including the aforementioned controller. Attached Figure Description

[0025] Figure 1 This is a block diagram of a differential control method provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of a vehicle powertrain provided in an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the differential of a vehicle's power system provided in an embodiment of the present invention.

[0028] The reference numerals in the accompanying drawings are as follows:

[0029] 10. Differential;

[0030] 1. Differential body; 11. Housing; 12. Planetary gear; 13. Planetary gear shaft; 14. First half-shaft gear; 15. Second half-shaft gear; 2. Differential lock; 3. Wheel end decoupling device;

[0031] 20. Drive motor; 30. First half-shaft; 40. First wheel; 50. Second half-shaft; 60. Second wheel; 70. Reduction mechanism; 701. First-stage reduction drive gear; 702. First-stage reduction driven gear; 703. Second-stage reduction drive gear; 704. Second-stage reduction driven gear; 80. Controller. Detailed Implementation

[0032] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the invention. Figure 1 In the diagram, the direction perpendicular to the paper is the Y-axis; for the X-axis and Z-axis, please refer to [reference needed]. Figure 2 The coordinates in the diagram.

[0033] See Figure 1 The vehicle control method provided in this embodiment of the invention includes:

[0034] Upon receiving a locking command, the system first controls the wheel-end decoupling device of the vehicle's differential to perform a coupling operation, and then controls the differential lock of the differential to perform a locking operation.

[0035] According to the vehicle control method of this invention, upon receiving a locking command, the wheel-end decouplers of the vehicle's differential are first controlled to perform a coupling operation, and then the differential lock of the differential is controlled to perform a locking operation. In this way, when the differential lock is locked, the wheel-end decouplers have already been coupled in advance. This avoids the locking failure problem caused by performing the locking operation in a wheel-end uncoupled state, as seen in related technologies, and ensures the normal operation of the differential lock.

[0036] In one embodiment, the step of first controlling the wheel-end decoupling device of the vehicle's differential to perform a coupling operation, and then controlling the differential lock of the differential to perform a locking operation, includes:

[0037] When the vehicle meets the locking enable condition, the differential lock is controlled to perform a locking operation, wherein the locking enable condition includes: the vehicle speed is less than a first target speed.

[0038] When the vehicle meets the forced coupling condition, the wheel-end decoupler is controlled to perform a coupling operation, wherein the forced coupling condition includes: the vehicle speed is less than the second target vehicle speed.

[0039] Wherein, the first target vehicle speed is less than the second target vehicle speed.

[0040] In one embodiment, the range of the first target vehicle speed is (0, 5) km / h.

[0041] In one embodiment, the range of the second target vehicle speed is: [5, 10) km / h.

[0042] Through autonomous vehicle speed control: first, the wheel-end decoupling device of the auxiliary drive of the four-wheel drive vehicle is controlled to perform a coupling operation, and then the differential lock of the auxiliary drive of the differential is controlled to perform a locking operation.

[0043] In one embodiment, when the vehicle meets the unlocking enable conditions, the differential lock is allowed to perform an unlocking operation, wherein the unlocking enable conditions include: the vehicle speed is greater than a third target speed, and the third target speed is greater than the second target speed.

[0044] When locked, the auxiliary drive will automatically unlock when the unlocking enable condition is met. For example, after getting out of trouble, the auxiliary drive will automatically switch to the unlocked state.

[0045] In one embodiment, the range of the third target vehicle speed is (30, 50) km / h.

[0046] In one embodiment, the vehicle is a four-wheel drive vehicle, which has a main drive and an auxiliary drive, and the differential is the differential of the auxiliary drive of the four-wheel drive vehicle. Both the main drive and the auxiliary drive have their own drive motors and differentials, and the differential includes a differential body (conventional differential), a differential lock, and wheel-end decoupling devices.

[0047] In one embodiment, it further includes:

[0048] When the vehicle meets the locking enable conditions, the differential lock is allowed to perform a locking operation. The locking enable conditions include: the vehicle speed is less than a first target speed, the speed difference between the connecting shafts at both ends of the wheel-end decoupler is less than a first target speed difference, and the vehicle's output torque is less than a first target torque. The inclusion of the vehicle's output torque being less than the first target torque in the locking enable conditions ensures smooth operation during differential lock locking and wheel-end decoupler coupling.

[0049] The locking of the differential lock corresponds to the extreme conditions of the vehicle, such as: slippage, off-road mode (potholes and uneven terrain), and get-out-of-trouble mode.

[0050] When the vehicle meets the coupling enable conditions, the wheel-end decoupler is allowed to perform coupling operation. The coupling enable conditions include: the speed difference between the connecting shafts at both ends of the wheel-end decoupler is less than a second target speed difference, and the output torque of the auxiliary drive is less than a first target torque, wherein the second target speed difference is less than the first target speed difference.

[0051] The coupling of the wheel-end decoupler allows the vehicle to switch from two-wheel drive to four-wheel drive. The smaller the speed difference between the connecting shafts at both ends of the wheel-end decoupler, the better the ride smoothness.

[0052] The differential lock operates when wheel slippage occurs, resulting in a speed difference between the left and right wheels. The wheel-end decoupling operates in two-wheel drive mode by cutting off the auxiliary drive torque and controlling the speed difference between the two connecting shafts of the wheel-end decoupling.

[0053] In one embodiment, the range of the first target speed difference is (30, 100) rpm.

[0054] In one embodiment, the range of the second target speed difference is (0, 30] rpm.

[0055] In one embodiment, when the auxiliary drive meets the forced coupling condition, the wheel-end decoupler of the auxiliary drive is controlled to perform a coupling operation, wherein the forced coupling condition includes: the speed of the four-wheel drive vehicle is greater than a fourth target speed, wherein the fourth target speed is greater than the third target speed.

[0056] When the vehicle is traveling at high speed, the wheel-end decoupling device needs to be coupled regardless of whether the auxiliary drive motor is working, in order to avoid damage to the differential.

[0057] In one embodiment, the range of the fourth target speed is (120, maximum permissible speed) km / h. The maximum permissible speed is the legally defined maximum speed. Setting the fourth target speed ensures the reliability of the differential and vehicle stability at high speeds.

[0058] In one embodiment, the control method further includes:

[0059] Detect vehicle speed; for example, by using a vehicle speed sensor.

[0060] Detect the vehicle's output torque.

[0061] In addition, this embodiment of the invention provides a controller 10, which operates according to the control method described in the above embodiment.

[0062] Additionally, see Figure 2 and Figure 3 This invention provides a vehicle including a powertrain and a controller 80. The powertrain includes a main drive and an auxiliary drive. Both the main drive and the auxiliary drive include their respective drive motors 20 and differentials 10. The differential 10 includes a differential body 1, a differential lock 2, and a wheel-end decoupling device 3.

[0063] Differential lock 2 is used for locking and unlocking the differential; wheel end decoupling device 3 is connected between one of the half-shaft gears of the differential body 1 and the half-shaft on the same side, and is used for coupling and decoupling the differential body 1 and the wheel connected to the half-shaft.

[0064] Specifically, see Figure 3 The differential body 1 includes a housing 11, planetary gears 12, a planetary gear shaft 13, a first half-shaft gear 14, and a second half-shaft gear 15. Both ends of the planetary gear shaft 13 are connected to the housing 11 and each is fitted with a planetary gear 12. The planetary gears 12, 14, and 15 are all bevel gears. The planetary gears 12 and 14 mesh orthogonally, and the planetary gears 12 and 15 mesh orthogonally. A wheel-end decoupling device 3 is connected between the inner end of the first half-shaft gear 14 and the inner end of the first half-shaft 30. The outer end of the first half-shaft 30 is connected to the first wheel 40. The second half-shaft gear 15 is connected to the second wheel 60 via the second half-shaft 50. The first half-shaft gear 14, 15, 30, and 50 are coaxial. A differential lock 2 is connected between the housing 11 and the second half-shaft 50.

[0065] The connecting shafts at both ends of the wheel end decoupler 3 are the output shafts of the first half-shaft 30 and the first half-shaft gear 14, respectively.

[0066] One of the first wheel 40 and the second wheel 60 is the left wheel, and the other is the right wheel.

[0067] Differential lock 2 is an electronic differential lock, such as an electromagnetic clutch. Wheel-end decoupling device 3 is, for example, an electromagnetic clutch.

[0068] See Figure 2 The controller 80 is connected to the differential lock 2, the wheel end decoupler 3 and the drive motor 20 respectively to control the locking and unlocking of the differential lock 2, the coupling and decoupling of the wheel end decoupler 3 and the operation of the drive motor 20.

[0069] The differentials in related technologies do not have wheel-end decoupling functionality. If reducing the drag torque of the drive motor is required to achieve energy saving, a separate wheel-end decoupling device is needed in the vehicle's powertrain. This results in the differentials in related technologies having drawbacks such as large space requirements, low integration, and limited functionality. In one embodiment of the invention, see... Figure 3 The differential lock 2 and the wheel end decoupling device 3 are integrated into the differential body 1. That is, the differential body 1, the differential lock 2 and the wheel end decoupling device 3 are integrated into the same housing 11 to form an integrated differential 10, which has the advantages of small footprint, high integration and multiple functions.

[0070] In addition, see Figure 2 The vehicle also includes a reduction gear 70, which is connected between the drive motor 20 and the housing 11 of the differential 1. The reduction gear 70 can be a single-gear or multi-gear reduction gear.

[0071] For example, in Figure 2 In the illustrated embodiment, the reduction mechanism 70 is a two-speed parallel shaft gear reduction mechanism. Specifically, the reduction mechanism 70 includes a first-stage reduction drive gear 701, a first-stage reduction driven gear 702, a second-stage reduction drive gear 703, and a second-stage reduction driven gear 704. The first-stage reduction drive gear 701 is connected to the output shaft of the drive motor 20. The first-stage reduction driven gear 702 and the second-stage reduction drive gear 703 are coaxially connected. The second-stage reduction driven gear 704 is fixed on the outer periphery of the housing 11 of the differential 1. The first-stage reduction drive gear 701 meshes with the first-stage reduction driven gear 702, and the second-stage reduction drive gear 703 meshes with the second-stage reduction driven gear 704.

[0072] The vehicle has a normal mode, an off-road mode, and an energy-saving mode. The control of the drive motor 20, differential lock 2, and wheel-end decoupling device 3 in each mode is shown in Table 1 below:

[0073] Table 1

[0074]

[0075] In normal mode, the wheel end decoupling device 3 is engaged and the differential lock 2 is disengaged. The torque of the drive motor 20 can be transmitted normally to the left and right wheels through the differential 1 and the left and right half shafts, enabling the vehicle to perform normal functions such as straight-line driving and differential cornering.

[0076] In the traction mode, the wheel-end decoupling device 3 engages and the differential lock 2 locks. The differential lock 2 rigidly connects the second half-shaft gear 15 to the housing 11 of the differential 1, so that the left and right wheels are rigidly connected and transmit the output torque of the drive motor 20 at the same speed, thereby improving the vehicle's traction capability.

[0077] In energy-saving mode, the wheel-end decoupling device 3 is disconnected, the differential lock 2 is disconnected, and the drive motor 20 is not working. The wheel (first wheel 40) on the side of the wheel-end decoupling device 3 is disconnected from the differential 1 and cannot transmit power. The other wheel (second wheel 60) drives the differential gear (planetary gear 12, first half-shaft gear 14 and second half-shaft gear 15) to rotate freely. The wheel cannot drive the housing 11 of the differential 1 to rotate, and thus cannot drive the drive motor 20 to rotate. This achieves decoupling between the wheel and the drive motor 20, eliminates the drag torque between the reduction mechanism 70 and the drive motor 20, thereby reducing the drag torque of the vehicle and achieving the purpose of energy saving and consumption reduction.

[0078] In another embodiment not shown in the figure, the differential lock 2 may be integrated into the housing 11 of the differential 1, and the wheel end decoupling device 3 may be disposed outside the housing 11 of the differential 1.

[0079] In another embodiment not shown in the figure, the wheel-end decoupling device 3 may be integrated into the housing 11 of the differential 1, and the differential lock 2 may be disposed outside the housing 11 of the differential 1.

[0080] In another embodiment not shown in the figure, the differential lock 2 and the wheel end decoupling device 3 may both be disposed outside the housing 11 of the differential 1.

[0081] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A vehicle control method, wherein the vehicle has a differential, the differential comprising a differential body, a differential lock, and wheel-end decoupling devices, characterized in that, The vehicle control method includes: Upon receiving a locking command, the system first controls the wheel-end decoupling device of the vehicle's differential to perform a coupling operation, and then controls the differential lock of the differential to perform a locking operation.

2. The control method according to claim 1, characterized in that, The steps of first controlling the wheel-end decoupling device of the vehicle's differential to perform a coupling operation, and then controlling the differential lock of the differential to perform a locking operation, include: When the vehicle meets the locking enable condition, the differential lock is controlled to perform a locking operation, wherein the locking enable condition includes: the vehicle speed is less than the first target vehicle speed; When the vehicle meets the forced coupling condition, the wheel-end decoupler is controlled to perform a coupling operation, wherein the forced coupling condition includes: the vehicle speed is less than the second target vehicle speed; Wherein, the first target vehicle speed is less than the second target vehicle speed.

3. The control method according to claim 2, characterized in that, The range of the first target vehicle speed is (0, 5) km / h.

4. The control method according to claim 2, characterized in that, The range of the second target vehicle speed is: [5, 10) km / h.

5. The control method according to claim 2, characterized in that, Also includes: When the vehicle meets the unlocking enable conditions, the differential lock is allowed to perform the unlocking operation, wherein the unlocking enable conditions include: the vehicle speed is greater than the third target speed, and the third target speed is greater than the second target speed.

6. The control method according to claim 5, characterized in that, The range of the third target vehicle speed is (30, 50) km / h.

7. The control method according to any one of claims 1-6, characterized in that, The vehicle is a four-wheel drive vehicle, and the differential is the auxiliary drive differential of the four-wheel drive vehicle.

8. The control method according to claim 7, characterized in that, Also includes: When the vehicle meets the locking enable conditions, the differential lock is allowed to perform a locking operation. The locking enable conditions include: the vehicle speed is less than the first target vehicle speed, the speed difference between the connecting shafts at both ends of the wheel-end decoupler is less than the first target speed difference, and the output torque of the vehicle is less than the first target torque. When the vehicle meets the coupling enable conditions, the wheel-end decoupler is allowed to perform coupling operation. The coupling enable conditions include: the speed difference between the connecting shafts at both ends of the wheel-end decoupler is less than a second target speed difference, and the output torque of the auxiliary drive is less than a first target torque, wherein the second target speed difference is less than the first target speed difference.

9. The control method according to claim 8, characterized in that, The range of the first target speed difference is (30, 100) rpm.

10. The control method according to claim 8, characterized in that, The range of the second target speed difference is (0, 30] rpm.

11. The control method according to claim 8, characterized in that, Also includes: When the auxiliary drive meets the forced coupling condition, the wheel-end decoupler of the auxiliary drive is controlled to perform a coupling operation. The forced coupling condition includes: the speed of the four-wheel drive vehicle is greater than the fourth target speed, wherein the fourth target speed is greater than the third target speed.

12. The control method according to claim 11, characterized in that, The range of the fourth target vehicle speed is (120, the maximum permissible speed) km / h.

13. A controller, characterized in that, The controller operates according to the control method described in any one of claims 1-12.

14. A vehicle, characterized in that, Includes the controller as described in claim 13.

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