VEHICLE STEERING DEVICE

• US 20150203147A1
• Filed: 01/20/2015
• Published: 07/23/2015
• Est. Priority Date: 01/20/2014
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Kuramochi, Toshikatsu, Yamazaki, Norio, Hanji, Munetsugu, Nakajima, Kenichi
• Granted Patent: US 9,701,334 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B62D 5/001 Mechanical components or aspects of steer-by-wire systems, not otherwise provided for in this maingroup
• CPC Class Codes: B62D 5/008 Changing the transfer ratio between the steering wheel and the steering gear by variable supply of energy, e.g. by using a superposition gear
• CPC Class Codes: B62D 5/0463 calculating assisting torque from the motor based on driver input
• CPC Class Codes: B62D 5/0496 by using a temperature sensor
• CPC Class Codes: B62D 6/008 Control of feed-back to the steering input member, e.g. simulating road feel in steer-by-wire applications

Abstract

A vehicle steering device includes a steering wheel operated by a driver to steer a vehicle; a steering reaction force motor that applies a reaction force to the steering wheel; a turning device that turns turning wheels of the vehicle by a turning motor; a clutch mechanism that mechanically connects and disconnects the steering wheel with and from the turning device; a control device that provides control so that a turning angle is based on a steering angle of the steering wheel; and a temperature sensor that measures a temperature. The vehicle steering device mechanically couples the steering wheel and the turning device and activates the steering wheel and the turning device if the temperature is a predetermined value or lower.

Claims

1. A vehicle steering device comprising:

a steering member operated by a driver to steer a vehicle;

a reaction force motor that applies a reaction force to the steering member;

a turning mechanism that turns turning wheels of the vehicle by a turning motor;

a clutch mechanism that mechanically connects and disconnects the steering member with and from the turning mechanism;

a control unit that provides control so that a turning angle is based on a steering angle of the steering member; and

a temperature acquisition section that can acquire a temperature by measuring or estimating the temperature,

wherein, if the temperature is a predetermined value or lower, the steering member and the turning mechanism are mechanically coupled and the vehicle steering device is activated.

2. The vehicle steering device according to claim 1, wherein the temperature acquisition section includes a temperature measurement unit connected with the control unit.

3. The vehicle steering device according to claim 1, wherein the temperature acquisition section acquires the temperature by estimating the temperature based on any of temperature information of an external thermometer, air-conditioner operation information, seat-heater temperature rise characteristic information, tire pressure information, information of a tire pressure monitoring system, information of a navigation device, and information received through the Internet.

4. The vehicle steering device according to claim 1, wherein, if a state, in which the temperature acquired by the temperature acquisition section is the predetermined value or lower, continues for a predetermined time or longer, the steering member and the turning mechanism are mechanically coupled and the vehicle steering device is activated.

5. The vehicle steering device according to claim 1, wherein, after the steering member and the turning mechanism are mechanically coupled and activated, if the temperature acquired by the temperature acquisition section exceeds the predetermined value, an operation mode is shifted to a steer by wire mode in which the steering member and the turning mechanism are not mechanically coupled.

6. The vehicle steering device according to claim 1, further comprising:

a turning motor current detection unit that detects a current value of the turning motor,

wherein, after the steering member and the turning mechanism are mechanically coupled and activated, if a current integrated value of the turning motor becomes a predetermined value or larger, an operation mode is shifted to a steer by wire mode in which the steering member and the turning mechanism are not mechanically coupled.

7. The vehicle steering device according to claim 1, wherein the activation while the steering member and the turning mechanism are mechanically coupled represents activation in an electronic power steering mode.

8. The vehicle steering device according to claim 7, wherein at least two motors are driven in the electronic power steering mode.

9. The vehicle steering device according to claim 8, further comprising:

a reaction force motor current detection unit that detects a current value of the reaction force motor,

wherein, after the steering member and the turning mechanism are mechanically coupled and activated, the reaction force motor is driven in the electronic power steering mode, and if a current integrated value of the reaction force motor is increased to a predetermined value, an operation mode is shifted to a steer by wire mode in which the steering member and the turning mechanism are not mechanically coupled.

10. The vehicle steering device according to claim 3, wherein the temperature is an ambient temperature surrounding the vehicle.

11. The vehicle steering device according to claim 2, wherein the temperature measurement unit measures a temperature of a turning gear box.

12. The vehicle steering device according to claim 8, wherein the at least two motors include the reaction force motor and the turning motor, and the at least two motors provide assist force for steering the vehicle.

13. The vehicle steering device according to claim 6, wherein the predetermined value is changed in accordance with the acquired temperature.

14. The vehicle steering device according to claim 9, wherein the predetermined value is changed in accordance with the acquired temperature.

15. A vehicle comprising the vehicle steering device according to claim 1.

16. A vehicle steering device comprising:

a steering device to steer a vehicle;

a reaction force motor that applies a reaction force to the steering device;

a turning mechanism that turns turning wheels of the vehicle by a turning motor;

a clutch mechanism that mechanically connects and disconnects the steering device with and from the turning mechanism;

a controller that controls the turning mechanism such that a turning angle of the turning wheels corresponds to a steering angle of the steering device; and

a temperature acquisition section that acquires a temperature by measuring or estimating the temperature,

wherein, if the temperature is a predetermined value or lower, the controller mechanically connects the steering device to the turning mechanism by the clutch mechanism and activates the vehicle steering device.

17. The vehicle steering device according to claim 16, wherein the temperature is a temperature around the turning mechanism.

18. A method for controlling a vehicle steering device, the vehicle steering device comprising:

a steering device to steer a vehicle;

a reaction force motor that applies a reaction force to the steering device;

a turning mechanism that turns turning wheels of the vehicle by a turning motor;

a clutch mechanism that mechanically connects and disconnects the steering device with and from the turning mechanism;

a controller that controls the turning mechanism such that a turning angle of the turning wheels corresponds to a steering angle of the steering device; and

a temperature acquisition section that acquires a temperature by measuring or estimating the temperature,

wherein, the method comprising;

obtaining a temperature around the vehicle;

deciding if the temperature is a predetermined value or lower; and

if the temperature is a predetermined value or lower, mechanically connecting, by using a computer, the steering device to the turning mechanism by the clutch mechanism and activating the vehicle steering device.