Vehicle equipped with electric motor and parking control method therefor

Patent metadata

Field	Value
Publication number	US-11453389-B2
Application number	US-202017094109-A
Country	US
Kind code	B2
Filing date	Nov 10, 2020
Priority date	Dec 11, 2019
Publication date	Sep 27, 2022
Grant date	Sep 27, 2022

Abstract

A method of parking control for a vehicle equipped with an electric motor independent from a transmission includes calculating external force applied to wheels when predetermined conditions including shifting to a parking (P) stage are satisfied, determining whether a drive shaft fixing apparatus activated according to shifting to the P stage is combined, and controlling the electric motor such that a torque having a magnitude less than the external force is applied to the wheels in a direction opposite to the external force when the drive shaft fixing apparatus is determined to be combined.

First claim

What is claimed is:

1. A method of parking control for a vehicle equipped with an electric motor independent from a transmission, the method comprising:
calculating external force applied to wheels when predetermined conditions including shifting to a parking (P) stage are satisfied;
determining whether a drive shaft fixing apparatus activated according to shifting to the P stage is combined; and
controlling the electric motor such that a torque having a magnitude less than the external force is applied to the wheels in a direction opposite to the external force when the drive shaft fixing apparatus is determined to be combined.

2. The method according to claim 1 , wherein the predetermined conditions are satisfied when brake operation and vehicle stop, shifting to the P stage, and cancellation of brake operation are sequentially performed.

3. The method according to claim 1 , wherein controlling the electric motor comprises controlling the electric motor such that the torque applied to the wheels and the external force have a predetermined difference therebetween.

4. The method according to claim 1 , further comprising controlling the electric motor such that a torque having a magnitude greater than the external force is applied to the wheels in a direction opposite to the external force when the drive shaft fixing apparatus is determined to be not combined.

5. The method according to claim 4 , wherein controlling the electric motor such that the torque having the magnitude greater than the external force is applied comprises limiting a rotation amount of the electric motor within a predetermined range.

6. The method according to claim 5 , wherein the predetermined range is determined in consideration of a sawtooth size of a parking gear of the drive shaft fixing apparatus.

7. The method according to claim 4 , wherein controlling the electric motor such that the torque having the magnitude greater than the external force is applied is performed until the drive shaft fixing apparatus is combined.

8. The method according to claim 4 , wherein controlling of the electric motor such that the torque having the magnitude greater than the external force is applied comprises controlling the electric motor such that the torque applied to the wheels and the external force have a predetermined difference therebetween.

9. The method according to claim 1 , wherein the electric motor has a drive shaft different from that of the transmission or is disposed in the wheels.

10. A non-transitory computer-readable recording medium storing a program for executing the method according to claim 1 .

11. A vehicle comprising:
a transmission;
an electric motor independent from the transmission;
a drive shaft fixing apparatus configured to be activated according to shifting to a parking (P) stage; and
a controller configured to:
calculate external force applied to wheels when predetermined conditions including shifting to the P stage are satisfied and to determine whether the drive shaft fixing apparatus activated according to shifting to the P stage is combined; and
determine a target torque of the electric motor such that a torque having a magnitude less than the external force is applied to the wheels in a direction opposite to the external force when the drive shaft fixing apparatus is determined to be combined.

12. The vehicle according to claim 11 , wherein the predetermined conditions are satisfied when brake operation and vehicle stop, shifting to the P stage, and cancellation of brake operation are sequentially performed.

13. The vehicle according to claim 11 , wherein the controller is configured to determine the target torque such that the torque applied to the wheels and the external force have a predetermined difference therebetween.

14. The vehicle according to claim 11 , wherein the controller is configured to determine the target torque such that a torque having a magnitude greater than the external force is applied to the wheels in a direction opposite to the external force when the drive shaft fixing apparatus is determined to be not combined.

15. The vehicle according to claim 14 , wherein the controller is configured to limit a rotation amount of the electric motor within a predetermined range.

16. The vehicle according to claim 15 , wherein the predetermined range is determined in consideration of a sawtooth size of a parking gear of the drive shaft fixing apparatus.

17. The vehicle according to claim 14 , wherein the controller is configured to determine the target torque such that the torque having a greater magnitude is applied until the drive shaft fixing apparatus is combined.

18. The vehicle according to claim 14 , wherein the controller is configured to determine the target torque such that the torque applied to the wheels and the external force have a predetermined difference therebetween.

19. The vehicle according to claim 11 , wherein the electric motor has a drive shaft different from that of the transmission or is disposed in the wheels.

20. The vehicle according to claim 11 , wherein the external force includes force applied to the vehicle due to a gradient of a road on which the vehicle stops.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Cho Jin Kyeom
• Jeon Sung Bae
• Son Hui Un

Classifications

• F16H63/486 Primary

  Common control of parking locks or brakes in the transmission and other parking brakes, e.g. wheel brakes · CPC title

• B60W10/18

  including control of braking systems · CPC title

• B60W10/08

  including control of electric propulsion units, e.g. motors or generators · CPC title

• B60W40/10

  related to vehicle motion · CPC title

• F16H2059/663

  Road slope · CPC title