Vehicle lamp unit and rotary light shielding member

Patent metadata

Field	Value
Publication number	US-10024513-B2
Application number	US-201615138575-A
Country	US
Kind code	B2
Filing date	Apr 26, 2016
Priority date	May 22, 2015
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

Provided is a vehicle lamp unit which includes an optical system configured to form a light distribution pattern ahead of a vehicle; and a rotary light shielding member configured to block at least a part of light of a light source. The rotary light shielding member includes a spiral light shielding portion formed to change a blocked quantity of light of the light source as the rotary light shielding member rotates around a rotating axis. The light shielding portion is configured to form a plurality of light distribution patterns such that a position of a cutoff line extending in a direction crossing a horizontal direction changes in the horizontal direction. Further, the light shielding portion is configured such that a change of a position of an edge portion projected as a cutoff line becomes nonlinear in relation to a change of a rotational position of the rotary light shielding member.

First claim

What is claimed is:

1. A vehicle lamp unit comprising:
an optical system configured to form a light distribution pattern ahead of a vehicle; and
a rotary light shielding member rotatable around a rotational axis thereof, and including a light shielding portion having a side surface continuously formed by a plurality of spiral surfaces where a plurality of edge portions are formed, and configured to block at least a part of light emitted from a light source,
wherein the plurality of spiral surfaces of the light shielding portion are formed to approach toward a left end of the rotary light shielding member, respectively, while rotating the rotary light shielding member toward a rear side of the vehicle around the rotational axis thereof when viewed in a front side of the vehicle, such that a blocked quantity of light emitted from the light source by the rotary light shielding member is changed,
the light shielding portion is configured to form a plurality of light distribution patterns including an inclined cutoff line extending in a direction that crosses a horizontal line, and a horizontal cutoff line connected to the inclined cutoff line, respectively such that a position of the inclined cutoff line moves along the horizontal line, while rotating the rotary light shielding member around the rotational axis, and
the light shielding portion is configured such that a change of a position of each of the plurality of edge portions of the side surface that is projected as the inclined cutoff line in a direction of the rotational axis of the rotary light shielding member becomes nonlinear in relation to a change of a rotational position of the rotary light shielding member while rotating the rotary light shielding member around the rotational axis thereof.

2. The vehicle lamp unit of claim 1 , wherein the plurality of light distribution patterns includes a first light distribution pattern, a second light distribution pattern, and a third light distribution pattern,
the plurality of edge portions of the side surface includes:
a first edge portion that is projected as a first inclined cutoff line of the first light distribution pattern in a first rotational position R 1 of the rotary light shielding member;
a second edge portion that is projected as a second inclined cutoff line of the second light distribution pattern in a second rotational position R 2 (R 1 <R 2 ) of the rotary light shielding member which is further rotated from the first rotational position R 1 ; and
a third edge portion that is projected as a third inclined cutoff line of the third light distribution pattern in a third rotational position R 3 (R 2 <R 3 ) of the rotary light shielding member which is further rotated from the second rotational position R 2 , and
the light shielding portion is configured such that a ratio ΔH/ΔR defined by a change ΔH from the first edge portion to the second edge portion in a direction of the rotational axis to a rotational change ΔR from the second rotational position R 1 to the second rotational position R 2 , is different from a ratio ΔH′/ΔR′ defined by a change ΔH′ from the second edge portion to the third edge portion in the direction of the rotational axis to a rotational change ΔR′ from the second rotational position R 2 to the third rotational position R 3 .

3. The vehicle lamp unit of claim 2 , wherein the light shielding portion is configured such that an area illuminated by the second light distribution pattern becomes larger than an area illuminated by the first light distribution pattern and narrower than an area illuminated by the third light distribution pattern, and meets a condition of the ratio ΔH/ΔR<the ratio ΔH′/ΔR′.

4. The vehicle lamp unit of claim 2 , wherein the light shielding portion is configured such that, assuming that a spiral surface which has a constant ratio ΔH″/ΔR″ defined by a change ΔH″ from the first edge portion to the third edge portion in the direction of the rotational axis to a rotational change ΔR″ from the first rotational position R 1 to the third rotational position R 3 is an imaginary surface α, an angle θ 1 formed between a first light shielding surface P 1 extending from the first edge portion to the second edge portion and the imaginary surface α is equal to or less than an angle θ 2 formed between a second light shielding surface P 2 extending from the second edge portion to the third edge portion and the imaginary surface α.

5. The vehicle lamp unit of claim 3 , wherein the light shielding portion is configured such that, assuming that a spiral surface which has a constant ratio ΔH″/ΔR″ of a change ΔH″ from the first edge portion to the third edge portion in the direction of the rotational axis to of a rotational change ΔR″ from the first rotational position R 1 to the third rotational position R 3 is an imaginary surface α, an angle θ 1 formed between a first light shielding surface P 1 extending from the first edge portion to the second edge portion and the imaginary surface α is equal to or less than an angle θ 2 formed between a second light shielding surface P 2 extending from the second edge portion to the third edge portion and the imaginary surface α.

6. The vehicle lamp unit of claim 2 , wherein the optical system includes a projection lens,
the rotary light shielding member is disposed near a focal point of the projection lens, and
the side surface of the light shielding portion serves as a light shielding surface which is curved about the second edge portion, and is configured such that a lower end of the second inclined cutoff line which is formed ahead of a vehicle when the second edge portion is projected in the second rotational position R 2 is disposed in a range of ±X H ° in a horizontal direction with reference to an optical axis of the projection lens [wherein X H is equal to or less than an angular difference X V between the lower end of the second inclined cutoff line and a line H-H (a horizontal line)].

7. The vehicle lamp unit of claim 3 , wherein the optical system includes a projection lens,
the rotary light shielding member is disposed near a focal point of the projection lens, and
the side surface of the light shielding portion serves as a light shielding surface which is curved about the second edge portion, and is configured such that a lower end of the second inclined cutoff line which is formed ahead of a vehicle when the second edge portion is projected in the second rotational position R 2 is disposed in a range of ±X H ° in a horizontal direction with reference to an optical axis of the projection lens [wherein X H is equal to or less than an angular difference X V between the lower end of the second inclined cutoff line and a line H-H (a horizontal line)].

8. The vehicle lamp unit of claim 4 , wherein the optical system includes a projection lens,
the rotary light shielding member is disposed near a focal point of the projection lens, and
the side surface of the light shielding portion serves as a light shielding surface which is curved about the second edge portion, and is configured such that a lower end of the second inclined cutoff line which is formed ahead of a vehicle when the second edge portion is projected in the second rotational position R 2 is disposed in a range of ±X H ° in a horizontal direction with reference to an optical axis of the projection lens [wherein X H is equal to or less than an angular difference X V between the lower end of the second inclined cutoff line and a line H-H (a horizontal line)].

9. The vehicle lamp unit of claim 5 , wherein the optical system includes a projection lens,
the rotary light shielding member is disposed near a focal point of the projection lens, and
the side surface of t

Assignees

• Koito Mfg Co Ltd

Inventors

• Yamamoto Teruaki
• Matsumoto Akinori

Classifications

• B60Q2300/40

  Indexing codes relating to other road users or special conditions · CPC title

• B60Q1/143

  combined with another condition, e.g. using vehicle recognition from camera images or activation of wipers · CPC title

• F21S41/25

  Projection lenses · CPC title

• F21S41/47

  Attachment thereof (achieving variable light distribution by movable screens F21S41/683) · CPC title

• B60Q2300/056

  Special anti-blinding beams, e.g. a standard beam is chopped or moved in order not to blind · CPC title