Power steering device

• US 5,762,160 A
• Filed: 04/04/1996
• Issued: 06/09/1998
• Est. Priority Date: 04/17/1995
• Status: Expired due to Fees

• Current Assignee: Koyo Seiko Co., Ltd. (Toyota Motor Corporation)
• Original Assignee: Koyo Seiko Co., Ltd. (Toyota Motor Corporation)
• Inventors: Shimizu, Yoshinobu
• Primary Examiner(s): DePumpo, Daniel G.
• Application Number:
  US08/625,851
• Time in Patent Office: 796 Days
• Field of Search: 180/167, 180/169, 180/421, 180/422, 180/443, 180/446
• US Class Current: 180/446
• CPC Class Codes: B62D 15/0265 Automatic obstacle avoidance by steering
• CPC Class Codes: B62D 5/0463 calculating assisting torque from the motor based on driver input
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/9315 Monitoring blind spots
• CPC Class Codes: G01S 2013/9318 Controlling the steering
• CPC Class Codes: G01S 2013/932 using own vehicle data, e.g. ground speed, steering wheel direction
• CPC Class Codes: G01S 2013/9323 Alternative operation using light waves
• CPC Class Codes: G01S 2013/9324 Alternative operation using ultrasonic waves
• CPC Class Codes: G01S 2013/93274 on the side of the vehicles

Abstract

A power steering device uses a control value set in accordance with a vehicle'"'"'s detected steering torque to control an actuator, which generates steering assistance power. When the vehicle appears to be on a collision course with an obstacle detected in its steering direction, the control value is modified so as to inhibit the steering. The control value after the modification for the steering inhibition is a function of the control value prior to the modification. When the detected value of the steering torque is greater than the preset value, the function is modified such that the degree of steering inhibition is increased by comparison with a situation in which the detected torque is less than the preset value.

Claims

1. A power steering device, comprising:

means for detecting a steering torque;

means for controlling the steering assistance power generation actuator by using a control value corresponding to the detected steering torque;

means for determining whether or not there is a possibility of collision between the vehicle and an obstacle detected in the steering direction; and

means for modifying said control value such that the vehicle'"'"'s steering is inhibited when there is the possibility of collision;

wherein;

the control value after the modification for the steering inhibition is a function of the control value prior to the modification; and

wherein;

when the detected steering torque is greater than a preset value, the function is modified such that the degree of steering inhibition is increased by comparison with a situation in which the detected steering torque is less than the preset value.

2. A power steering device, comprising:

means for detecting a steering torque;

means for controlling the steering assistance power generation actuator by using a control value corresponding to the detected steering torque;

means for determining whether or not there is a possibility of collision between the vehicle and an obstacle detected in the steering direction; and

means for modifying said control value such that the vehicle'"'"'s steering is inhibited when there is the possibility of collision;

wherein;

the control value after the modification for the steering inhibition is a function of the control value prior to the modification; and

wherein;

when the rate of change of the detected steering torque is greater than a preset value, the function is modified such that the degree of steering inhibition is increased by comparison with a situation in which the rate of change of the detected steering torque is less than the preset value.

4. The power steering device according to claim 2, wherein:

when the rate of change of the detected steering torque is greater than the preset value, the control value after modification is determined such that the degree of steering inhibition is gradually reduced.

3. A power steering device, comprising:

means for detecting a steering torque;

means for controlling the steering assistance power generation actuator by using a control value corresponding to the detected steering torque;

means for determining whether or not there is a possibility of collision between the vehicle and an obstacle detected in the steering direction; and

means for modifying said control value such that the vehicle'"'"'s steering is inhibited when there is the possibility of collision;

wherein;

the control value after the modification for the steering inhibition is a function of the control value prior to the modification;

wherein;

when the detected steering torque is greater than a preset value, the function is modified such that the degree of steering inhibition is increased by comparison with a situation in which the detected steering torque is less than the preset value; and

wherein;

when the rate of change of the detected steering torque is greater than a preset value, the function is modified such that the degree of steering inhibition is increased by comparison with a situation in which the rate of change of the detected steering torque is less than the preset value.

5. The power steering device according to claim 3, wherein:

when the rate of change of the detected steering torque is greater than the preset value, the control value after modification is determined such that the degree of steering inhibition is gradually reduced.