Headlight control device and method for vehicles

• US 20070268159A1
• Filed: 05/16/2007
• Published: 11/22/2007
• Est. Priority Date: 05/18/2006
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Futamura, Shinichi
• Granted Patent: US 7,898,182 B2
• Time in Patent Office: Days
• US Class Current: 340/933
• CPC Class Codes: B60Q 1/143 combined with another condition, e.g. using vehicle recognition from camera images or activation of wipers
• CPC Class Codes: B60Q 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/122 Steering angle
• CPC Class Codes: B60Q 2300/21 Manual control
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/314 Ambient light

Abstract

If a beam state of headlight is manually switched over in a manual control mode, threshold values of vehicle speed, steering angle or the like, are learned for determining the switching over to the low-beam state or to the high-beam state based on the results detected by a speed sensor, illumination sensor, steering angle sensor and weather sensor, and are stored in a nonvolatile memory. In an automatic control mode, a CPU determines the switching over to the low-beam state or to the high-beam state based on the traveling condition detected by the illumination sensor by using the threshold values for determining the switching over learned in the manual control mode. The CPU automatically switches over the state of the beam of the headlight based upon the determination result.

Claims

1. A headlight control device for vehicles comprising:

manual switching means for manually switching over an illumination state of a headlight between a first illumination state and a second illumination state where the amount of illumination to a distance is larger than that in the first illumination state;

traveling condition detector means for detecting a traveling condition of the vehicle;

automatic switching means for automatically switching over the illumination state of the headlight between the first illumination state and the second illumination state depending upon the traveling condition detected by the traveling condition detector means; and

learning means for learning a threshold value for determining switching over between the first illumination state and the second illumination state based on the traveling condition detected by the traveling condition detector means when the illumination state of the headlight is manually switched by the manual switching means,

wherein the automatic switching means determines the switching over between the first illumination state and the second illumination state by using threshold value for determining the switching over learned by the learning means.

2. The headlight control device for vehicles according to claim 1, wherein the learning means learns the threshold value for determining the switching over during a predetermined learning condition.

3. The headlight control device for vehicles according to claim 2, wherein the learning condition includes a case where a value representing the traveling condition detected by the traveling condition detector means at the time of manual switching is a normal value.

4. The headlight control device for vehicles according to claim 2, further comprising:

mode switching means for switching over an operation mode between an automatic control mode which enables the operation of the automatic switching means and a manual control mode which inhibits the operation of the automatic switching means,

wherein the learning condition includes a case where the manual control mode is being assumed.

5. The headlight control device for vehicles according to claim 1, wherein the learning means learns the threshold value for determining the switching over by moderating the value representing the traveling condition detected by the traveling condition detector means at the time of manual switching.

6. The headlight control device for vehicles according to claim 1, further comprising:

adjusting means for adjusting the threshold value for determining the switching over.

7. The headlight control device for vehicles according to claim 1, wherein the traveling condition detector means includes front illumination detector means for detecting front illumination, and the learning means learns a threshold illumination level as the threshold value for determining the switching over.

8. The headlight control device for vehicles according to claim 1, wherein the traveling state detector means includes vehicle speed detector means for detecting a vehicle speed, and the learning means learns a threshold vehicle speed as the threshold value for determining the switching over.

9. The headlight control device for vehicles according to claim 1, wherein the traveling condition detector means includes turning condition detector means for detecting a turning condition, and the learning means learns a threshold value related to the turning condition as the threshold value for determining the switching over.

10. The headlight control device for vehicles according to claim 1, wherein the traveling condition detector means includes weather condition detector means for detecting a weather condition, and the learning means learns a threshold value related to the weather condition as the threshold value for determining the switching over.

11. A headlight control method for vehicles comprising:

detecting a traveling condition of a vehicle;

automatically switching over an illumination state of a headlight between a first illumination state and a second illumination state depending upon a comparison of a detected traveling condition with a threshold value, the amount of illumination to a distance being larger in the second illumination state than that in the first illumination state; and

learning the threshold value for determining automatic switching over between the first illumination state and the second illumination state based on the traveling condition detected when the illumination state of the headlight is manually switched over by a manual switch.

12. The headlight control method according to claim 11, wherein the learning learns the threshold value only in a predetermined learning condition in which the detected traveling condition at the time of manual switching over is not an abnormal value.

13. The headlight control method according to claim 11, wherein the learning learns, as the threshold value, at least one of a vehicle front illumination level, a vehicle speed, a vehicle turning condition, and a weather condition.

14. The headlight control method according to claim 11, further comprising:

delaying the automatic switching over from the first illumination state to the second illumination state for a predetermined time after a determination of switching over based on the comparison of the detected traveling condition.