Vehicular headlamp apparatus

• US 7,021,791 B1
• Filed: 03/24/2000
• Issued: 04/04/2006
• Est. Priority Date: 03/26/1999
• Status: Active Grant

• Current Assignee: Koito Manufacturing Company Limited
• Original Assignee: Koito Manufacturing Company Limited
• Inventors: Kobayashi, Shoji
• Primary Examiner(s): Quach-Lee, Y. My
• Application Number:
  US09/535,939
• Time in Patent Office: 2,202 Days
• Field of Search: 362/212, 362/214, 362/464, 362/465, 362/508, 362/510, 362/512, 362/539, 362/282, 362/284, 362/322, 362/324
• US Class Current: 362/212
• 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 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/21 Manual control
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/336 Crossings
• CPC Class Codes: F21S 41/14 characterised by the type of light source
• CPC Class Codes: F21S 41/334 the reflector consisting of patch like sectors
• CPC Class Codes: F21S 41/43 characterised by the shape thereof
• CPC Class Codes: F21S 41/692 Shields, i.e. screens not creating an image meant to be projected

Abstract

A vehicular headlamp apparatus 1 is provided with a first and a second light-emitting portion including a common light source 3 or a plurality of light sources 3 and 3′. The first light-emitting portion 2_1 forms a base beam by normally lighting the light source 3 to use emission light from the light source. The second light-emitting portion 2_2 is caused to emit an auxiliary beam for supplementing the light distribution of the base beam made available by the first light-emitting portion 2_1. The distribution, the quantity of light or light color of the light emitted from the first light-emitting portion 2_1 is varied with the travel condition or travel environment of a vehicle.

Claims

1. A vehicular headlamp apparatus comprising:

(i) a first light-emitting portion that forms a base beam by reflecting light from a first light source;

(ii) a second light-emitting portion that forms a second light beam by reflecting light from a second light source, a light distribution of the second light beam supplements a light distribution of the base beam; and

(iii) a light emission control means for varying the light distribution of the second light beam formed by adjusting the light distribution formed by the second light-emitting portion based on travel environment information,

wherein the light distribution of the base beam is used as a low beam and wherein a light distribution of part of a high beam is used for irradiating a forward field of the vehicle in a wide range and further wherein the second light beam is formed by using a peripheral zone of a reflective surface of a reflector.

2. The vehicular headlamp apparatus as claimed in claim 1, wherein the second light beam is used for irradiating a center line of a roadway or the shoulder thereof.

3. The vehicular headlamp apparatus as claimed in claim 1, wherein the second light beam is emitted to irradiate a field on and near a cutoff that divides the distribution of the low beam into a light and a shade side with a boundary between the light side and the shade side.

4. The vehicular headlamp apparatus as claimed in claim 1, wherein

(i) the first light source is from at least the low beam and the high beam, and

(ii) the second light-emitting portion includes a plurality of luminescent portions, whereby an irradiation range is changed by switching the plurality of luminescent portions.

5. The vehicular headlamp apparatus as claimed in claim 1, wherein the second light-emitting portion includes a plurality of luminescent portions, whereby an irradiation range is changed by switching the plurality of luminescent portions.

6. The vehicular headlamp apparatus as claimed in claim 1, wherein the second light-emitting portion includes a luminescent portion having two filaments, and wherein the two filaments are disposed such that a central axis of the filaments extends along an optical axis of the second light-emitting portion.

7. The vehicular headlamp apparatus as claimed in claim 6, wherein one of the filaments irradiates a remote side area irradiation beam and a near side area irradiation beam.