Vehicle headlamp device

• US 6,443,602 B1
• Filed: 02/03/2000
• Issued: 09/03/2002
• Est. Priority Date: 03/01/1999
• Status: Expired due to Fees

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: Fukuwa, Shinji, Tanabe, Toru
• Primary Examiner(s): Husar, Stephen
• Assistant Examiner(s): Lee, Guiyoung
• Application Number:
  US09/497,811
• Time in Patent Office: 943 Days
• Field of Search: 362/53, 362/464, 362/465, 362/466, 362/467, 362/276, 362/212, 315/79, 315/82, 315/81, 340/469, 340/458, 340/468
• US Class Current: 362/465
• CPC Class Codes: B60Q 1/085 due to special conditions, e.g. adverse weather, type of road, badly illuminated road signs or potential dangers B60Q1/10, B60Q1/12, B60Q1/1423 take precedence
• CPC Class Codes: B60Q 1/12 due to steering position
• CPC Class Codes: B60Q 1/18 being additional front lights bracket mounted headlights B60Q1/0483
• CPC Class Codes: B60Q 2300/054 Variable non-standard intensity, i.e. emission of various beam intensities different from standard intensities, e.g. continuous or stepped transitions of intensity
• CPC Class Codes: B60Q 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/122 Steering angle
• CPC Class Codes: B60Q 2300/128 Steering dead zone
• CPC Class Codes: H05B 41/42 in two steps only

Abstract

A vehicle headlamp device 10 can be equipped with a discharge lamp 11, a beam switch device 13 that is used to switch between the high beam and low beam, a light distribution switch device 14 which broadens the horizontal light distribution in the forward direction of the vehicle during cornering, and a lighting device 20 which supplies electric power to the discharge lamp. The light distribution switch device 14 can be controlled such that the horizontal light distribution is broadened in the forward direction when the vehicle speed and steering angle exceed specified values. The lighting device 20 can be controlled such that the electric power supplied to the discharge lamp increases only when the horizontal light distribution is broadened by the light distribution switch device 14.

Claims

1. A vehicle headlamp device for connection to a vehicle, comprising:

a light source connectable to a front of the vehicle and configured to produce a light beam;

means for switching between a high beam and a low beam located adjacent to said light source;

means for broadening a horizontal light distribution of said light beam in a direction of travel of the vehicle during cornering, said means for broadening a horizontal light distribution located adjacent said light source; and

a lighting device configured to receive a vehicle speed detection signal and a steering angle detection signal, said lighting device controlling electric power to said light source and said means for broadening a horizontal light distribution, such that electric power supplied to said light source increases, and said horizontal light distribution is broadened in the direction of travel of the vehicle, when the vehicle speed detection signal and the steering angle detection signal exceed predetermined values.

2. The vehicle headlamp device of claim 1, wherein said lighting device increases said electric power in synchronization with operation of said means for broadening a horizontal light distribution.

3. The vehicle headlamp device of claim 1, wherein said means for broadening a horizontal light distribution is constructed such that said light distribution is maximally broadened when said steering angle detection signal exceeds a predetermined maximum value, and

said increase in electric power effected by said lighting device is performed at a constant rate of increase when said steering angle detection signal exceeds said predetermined value.

4. The vehicle headlamp device of claim 1, wherein said means for broadening a horizontal light distribution is constructed such that said light distribution is gradually broadened in accordance with the steering angle detection signal, and

said lighting device is configured to control the electric power to gradually increase in accordance with the steering angle detection signal.

5. The vehicle headlamp device of claim 1, wherein said lighting device returns said electric power to its original value when the vehicle speed detection signal drops below a predetermined low value.

6. The vehicle headlamp device of claim 1, wherein said lighting device is controlled such that the electric power supplied to said light source is increased when said light beam is switched to high beam by said means for switching between high beam and low beam.

7. The vehicle headlamp device of claim 6, wherein said lighting device includes a microcomputer which increases the electric power of said lighting device based on one of:

1) the vehicle speed detection signal;

     2) the steering angle detection signal;

     3) a beam switching command signal emitted from said means for switching between high and low beam; and

     4) a combination of the vehicle speed detection signal, the steering angle detection signal and the beam switching command signal.

8. The vehicle headlamp device of claim 1, wherein said increase in electric power effected by said lighting device is approximately a 5% to 20% increase.

9. The vehicle headlamp device of claim 1, wherein the device is constructed as a two-lamp system in which said light source is configured for placement on the right front side of the vehicle and a second left light source is configured for placement on the left front side of the vehicle.

10. The vehicle headlamp device of claim 1, further comprising:

a first left light source configured for placement on the left front of the vehicle;

a second left light source configured for placement on the left front of the vehicle;

a second right light source configured for placement on the right front of the vehicle,

wherein said light source is configured for placement on the right front of the vehicle and the vehicle headlamp device is constructed as a four-lamp system.

11. The vehicle headlamp device of claim 1, wherein said light source is a discharge lamp.

12. The vehicle headlamp device of claim 1, further comprising:

a vehicle speed detector for detecting the speed of the vehicle; and

a vehicle steering angle detector for detecting the steering angle of the vehicle.

13. The vehicle headlamp device of claim 1, wherein said means for switching between a high beam and a low beam includes a moveable hood positioned adjacent said light source.

14. The vehicle headlamp device of claim 1, wherein said means for broadening a horizontal light distribution includes a reflective member that is split into an upper portion and a lower portion in a horizontal direction, and said upper portion connected to rotate with respect to said lower portion such that said upper portion can reflect light in a different direction as compared to said lower portion.

15. A vehicle headlamp device for connection to a vehicle, comprising:

a light source connectable to a front of the vehicle;

a vertical light directing structure located adjacent said light source and configured to direct a light beam emitted from said light source in one of a low beam direction in which said light beam is directed away from the front of the vehicle, and a high beam direction in which said light beam is directed away from the front of the vehicle and at a higher vertical angle relative to said low beam direction;

a horizontal light directing structure located adjacent said light source and configured to direct a light beam emitted from said light source in one of a normal beam direction in which said light beam is directed away from the front of the vehicle, and a wide beam direction in which said light beam is directed away from the front of the vehicle and at a larger horizontal angle relative to said low beam direction; and

a lighting device configured to receive a vehicle steering angle signal and a vehicle speed signal, and to increase electric power to said light source when the vehicle speed signal and steering angle signal exceed predetermined values.

16. The vehicle headlamp device of claim 15, wherein said lighting device increases electric power in synchronization with operation of said vertical light directing structure.

17. The vehicle headlamp device of claim 15, wherein said horizontal light directing structure is controlled by said lighting device such that a horizontal light distribution is maximally broadened when the steering angle signal exceeds a predetermined maximum value.

18. The vehicle headlamp device of claim 15, wherein said increase in electric power effected by said lighting device is performed at a constant rate of increase when the steering angle exceeds said predetermined value.

19. The vehicle headlamp device of claim 15, wherein said horizontal light directing structure is controlled by said lighting device such that a horizontal distribution of light is gradually broadened in accordance with the detected steering angle signal, and

said increase in electric power is controlled by said lighting device such that electric power is gradually increased in accordance with the detected steering angle signal.

20. The vehicle headlamp device of claim 15, wherein said lighting device returns the electric power to its original value when the detected vehicle speed signal drops below a predetermined low value.

21. The vehicle headlamp device of claim 15, further comprising:

a high beam/low beam switch, wherein said lighting device increases electric power supplied to said light source when said light beam is switched to high beam by said high beam/low beam switch.

22. The vehicle headlamp device of claim 21, wherein said lighting device includes a microcomputer which increases electric power of said lighting device based on one of:

1) the detected vehicle speed signal;

     2) the detected steering angle signal;

     3) a beam switching command signal emitted from said high beam/low beam switch; and

     4) a combination of the detected vehicle speed signal, the detected steering angle signal and the beam switching command signal.

23. The vehicle headlamp device of claim 15, wherein the increase in electric power effected by said lighting device is approximately a 5% to 20% increase.

24. The vehicle headlamp device of claim 15, wherein the device is constructed as a two-lamp system in which said light source is configured for placement on the right front side of the vehicle and a second left light source is configured for placement on the left front side of the vehicle.

25. The vehicle headlamp device of claim 15, further comprising:

a first left light source configured for placement on the left front of the vehicle;

a second left light source configured for placement on the left front of the vehicle;

a second right light source configured for placement on the right front of the vehicle,

wherein said light source is configured for placement on the right front of the vehicle and the vehicle headlamp device is constructed as a four-lamp system.

26. The vehicle headlamp device of claim 15, wherein said light source is a discharge lamp.

27. The vehicle headlamp device of claim 15, further comprising:

a vehicle speed detector for detecting the speed of the vehicle and outputting said speed signal to said lighting device; and

a vehicle steering angle detector for detecting the steering angle of the vehicle connected to said lighting device and outputting said steering angle signal to said lighting device.

28. The vehicle headlamp device of claim 15, wherein said vertical light directing structure includes a moveable hood positioned adjacent said light source.

29. The vehicle headlamp device of claim 15, wherein said horizontal light directing structure includes a reflective member that is split into an upper portion and a lower portion in a horizontal direction, and said upper portion connected to rotate with respect to said lower portion such that said upper portion can reflect light in a different direction as compared to said lower portion.

30. A method of controlling illumination of a headlamp in a vehicle, the headlamp having a light source including light directing structures proximate the headlamp, the method comprising:

sensing at least one of a vehicle speed signal and a vehicle steering signal;

supplying electric power to the lightsource at a predetermined electric power; and

increasing electric power to the lightsource whenever the vehicle speed signal and vehicle steering signal reach predetermined values.

31. The method as claimed in claim 30, further comprising reducing the electric power to the light source whenever one of the vehicle speed signal and vehicle steering signal is not greater than the predetermined values.