Projection headlamp for vehicles

• US 5,379,196 A
• Filed: 06/03/1993
• Issued: 01/03/1995
• Est. Priority Date: 06/05/1992
• Status: Expired due to Fees

• Current Assignee: Koito Manufacturing Company Limited
• Original Assignee: Koito Manufacturing Company Limited
• Inventors: Kobayashi, Shoji, Ishikawa, Masaaki, Hayami, Toshihisa
• Primary Examiner(s): Lazarus, Ira S.
• Assistant Examiner(s): CARIASO, ALAN B
• Application Number:
  US08/070,902
• Time in Patent Office: 579 Days
• Field of Search: 362/61, 362/282, 362/283, 362/284, 362/319, 362/322, 362/323, 362/324, 362/360, 362/308, 362/343, 362/347
• US Class Current: 362/466
• 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 1/122 with electrical actuating means details of the electric drive components, e.g. motors, shafts, ball joints B60Q1/076
• CPC Class Codes: B60Q 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/114 Vehicle acceleration or deceleration
• CPC Class Codes: B60Q 2300/132 Pitch
• CPC Class Codes: B60Q 2300/41 preceding vehicle
• CPC Class Codes: B60Q 2300/42 oncoming vehicle
• CPC Class Codes: F21S 41/698 Shaft-shaped screens rotating along its longitudinal axis

Abstract

A projection headlamp for vehicles has a substantially elliptical reflector 14, a light source (bulb) located at the first focal point F1 of the reflector 14, a projection lens 16 disposed in front of the reflector 14, and a shade 20 located at a position near to the second focal point F2 and the focal point of the projection lens 16. The shade 20 partially intercepts light beams going from the reflector 14 toward the projection lens 16. The shade 20 is allowed to turn about the horizontal shaft 23 of the reflector 14 to adjust the beam distribution pattern. The shade 14 includes right and left shades 21 and 22, which are separated and horizontally extended when seen from the point substantially right under the optical axis L, and are allowed to independently turn about the horizontal shaft 23.

Claims

1. A projection type headlamp, comprising:

a substantially oval reflector;

a light source disposed at a first focal point of said reflector;

a projection lens disposed in front of said reflector; and

shade means for cutting at a predetermined position a part of light beam emitted from said light source and reflected by said reflector, said shade means being provided between said reflector and said projection lens in the vicinity of a second focal point of said reflector and substantially at a focus point of said projection lens, said shade means rotating along a horizontal axis thereof for forming variable light distribution patterns, said shade means comprising;

a first shade member rotatably supported on said horizontal axis; and

a second shade member rotatably supported on said horizontal axis and rotating therealong independently from said first shade member.

2. The projection type headlamp of claim 1, wherein each of said first and second shade members comprises a substantially tubular body.

3. The projection type headlamp of claim 1, wherein at least one of said first and second shade members is eccentrically supported on said horizontal axis.

4. The projection type headlamp of claim 3, wherein merely first shade member is eccentrically supported on said horizontal axis.

5. The projection type headlamp of claim 3, wherein both said first and second shade members are eccentrically supported on said horizontal axis.

6. The projection type headlamp of claim 2, wherein a diameter of said first shade member is different from that of said second shade member.

7. The projection type headlamp of claim 1, further comprising:

a first drive means for operatively engaging with said first shade member through a first gear means; and

,

a second drive means for operatively engaging with said second shade member through a second gear means separate from said first drive motor.

8. The projection type headlamp of claim 7, wherein said first and second drive means comprise an electric motor controlled by a central processing unit.