JP4962869B2 - Vehicle lighting - Google Patents

Description

  The present invention relates to a vehicular lamp used for a headlamp, a fog lamp, or the like of an automobile.

  2. Description of the Related Art As a headlamp of an automobile, there is known a headlamp having two thin plate structures, in which a light distribution formed from each of these shades is overlapped to form a predetermined light distribution pattern.

In this headlamp, two thin plate shades are arranged at a required interval between a projection lens and a reflector, and a cut-off line is formed at the upper edge by a light / dark boundary forming portion at the upper end of each shade. A low beam light distribution pattern for passing is formed (see Patent Document 1).
JP 2004-172104 A

  The two front and rear shades are arranged with the bright and dark boundary forming portions at the upper ends aligned on the optical axis extending in the vehicle front-rear direction of the projection lens.

  For this reason, the cut-off line formed at the light-dark boundary forming part of the front shade and the cut-off line formed at the light-dark boundary forming part of the rear shade appear almost overlapping on the light distribution pattern.

  As a result, the cut-off line of the light distribution pattern becomes clear, and the difference in brightness near the cut-off line becomes remarkable. As a result, for the driver, the amount of light suddenly decreases on the upper side of the cut-off line of the light distribution pattern, and the forward visibility deteriorates.

  Therefore, the present invention provides a vehicular lamp that can obtain a light distribution pattern with excellent visibility by deceiving a cut-off line in a low-beam light distribution pattern for passing and reducing a difference in brightness near the cut-off line. It is to provide.

In the vehicular lamp according to the present invention, a projection lens having an optical axis extending in the vehicle front-rear direction, a light source disposed on the optical axis behind the projection lens, and disposed around the light source, Before and after a reflector that reflects light from a light source toward the projection lens and between the projection lens and the reflector and blocks a part of the reflected light from the reflector to form a predetermined light distribution pattern With two shades,
In the vehicular lamp that forms the cut-off line of the light distribution pattern by the light / dark boundary forming portion provided at the upper ends of the two shades,
At least part of the light / dark boundary forming part in the front shade on the projection lens side is formed at a height different from the height of the light / dark boundary forming part in the rear shade on the reflector side ,
Reflective surfaces are formed on the inner surfaces of the front and rear shades facing each other,
A reflected light extraction part is partially formed on the front shade,
A part of the reflected light from the reflector, the light incident between the front and rear shade light / dark boundary forming portions is reflected by the opposing reflective surfaces, and the light reflected by the rear shade reflective surface is reflected. The light is extracted from the light extraction portion in the vicinity of the cut-off line of the light distribution pattern .

  According to the present invention, at least a part of the light / dark boundary forming part in the front shade on the projection lens side is formed at a height different from the height of the light / dark boundary forming part in the rear shade on the reflector side. In a portion where the length is different, the cut-off line light distribution by the front shade and the cut-off line light distribution by the rear shade are shifted in the vertical direction.

  Thereby, the two cut-off line light distributions shifted in the vertical direction are combined, the cut-off line is turned off, the light / dark difference in the vicinity of the cut-off line is reduced, and a light distribution pattern with excellent visibility is obtained.

  Further, if a part of the light incident between the front shade and the rear shade is irradiated as additional light in the vicinity of the cut-off line from the reflected light extraction part partially provided on the front shade, It is also possible to mitigate the difference in light and darkness near the cut-off line by deceiving the cut-off line with additional light.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings, taking an automobile headlamp as an example.

  1 to 6 show an embodiment of a headlamp according to the present invention, FIG. 1 is a schematic cross-sectional explanatory view showing an optical path state with the headlamp as a vertical cross section, and FIG. 2 is an upper central portion of the front and rear shades. FIG. 3 is a perspective view showing an optical path state in the upper center portion of the front and rear shades, FIG. 4 is a cross-sectional view taken along line AA in FIG. 2, and FIG. 5 is a virtual vertical arranged in front of the vehicle. FIG. 6 is an explanatory diagram showing the cross-sectional illuminance along the line BB in FIG. 5.

  As shown in FIG. 1, a headlamp 1 according to this embodiment includes a discharge lamp 2 as a light source, a reflector 3 that covers the periphery of the discharge lamp 2, and a projection lens 4 that irradiates reflected light from the reflector 3 to the front of the vehicle. The projector-type lamp is provided with two shades 5 and 6 before and after forming a predetermined light distribution pattern, and is disposed in a lamp chamber partitioned by a lamp housing and an outer cover (not shown). .

  As the discharge lamp 2, a metal highland lamp or the like is used, a light emitting portion is positioned on the optical axis X of the projection lens 4 extending in the vehicle front-rear direction, and attached to the rear portion of the reflector 3 via a socket (not shown). Yes.

  The reflector 3 is fixed to the rear end of the substantially cylindrical holder 7.

  The reflecting surface 3a of the reflector 3 is formed as a free-form surface based on a spheroid having the optical axis X as a major axis (reference, basic tone).

Then, the light emitting portion of the discharge lamp 2 is disposed substantially focal point of the spheroid underlying (first focal point F _1).

Thus, the reflection surface 3a is the light from the discharge lamp 2 is reflected forward, it is substantially converged at the second focal point F ₂ of the spheroid underlying.

  The projection lens 4 is a plano-convex lens having a convex front surface and a flat rear surface.

The projection lens 4 is fixed to the front end of the holder 7, the rear side focal position is in the middle of the front shade 5 and the rear shade 6, the second focal point F ₂ of the reflecting surface 3a of the reflector 3, the rear side this In the vicinity of the focal point.

  The two front and rear shades 5 and 6 are arranged between the reflector 3 and the projection lens 4 to block a part of the reflected light from the reflector 3 and to pass the low beam light distribution pattern PL for passing shown in FIG. Is formed.

  In the present embodiment, the length of the front shade 5 in the vertical direction is shorter than the rear shade 6 fixed to the bottom of the holder 7, and both end portions extending in the left-right direction are formed at both end portions of the rear shade 6. It is fixed.

  A required clearance S is provided between the front shade 5 and the rear shade 6 as shown in FIG.

  The upper ends of the front shade 5 and the rear shade 6 are arranged in the vicinity of the optical axis X and extend horizontally in the left-right direction.

  At the upper ends of the front shade 5 and the rear shade 6, light / dark boundary forming portions 5A and 6A for forming the cut-off line CL of the light distribution pattern PL are formed.

In the present embodiment, as shown in FIGS. 2 to 4, the light / dark boundary forming portions 5 </ b> A and 6 </ b> A are both inclined at the center 5 </ b> A ₁ and 6 </ b> A when viewed from the front (see the shades 5 and 6 from the projection lens 4). ₁ , the right edge 5A ₂ , 6A ₂ is high, and the left edge 5A ₃ , 6A ₃ is low.

  As a result, as shown in FIG. 5, a low beam light distribution pattern PL for passing having a stepped cut-off line CL which is low on the opposite lane side and high on the own lane side is obtained.

Here, the right edge 5A ₂ of the front shade 5 is formed to be higher than the right edge 6A ₂ of the rear shade 6.

Accordingly, so as to shift downward than the cut-off line light distribution L ₂ by the right edge 6A ₂ cut by the right edge 5A ₂ of the front shade 5 offline light distribution L ₁ is, the rear shade 6 as shown in FIG. 1 It has become.

  Reflecting surfaces 8 and 9 are formed on inner surfaces of the front shade 5 and the rear shade 6 facing each other. These reflecting surfaces 8 and 9 may be the material of the front and rear shades 5 and 6, for example, a cloth such as aluminum or resin.

  On the other hand, the reflected light extraction part 10 is partially formed in the front shade 5 at a position lower than the light / dark boundary forming part 6A of the rear shade 6.

Figure 2 in the example shown in Figure 4, the left side edge 5A ₃ of the front shade 5, by forming the rear shade 6 lower height than the left edge 6A ₃ of a portion of the left side edge 5A ₃ reflected light The take-out unit 10 is used.

  According to the headlamp 1 of the present embodiment having the above configuration, when the discharge lamp 2 is turned on, the light is reflected by the reflecting surface 3a of the reflector 3 as shown in FIG.

This reflected light is substantially converged on the second focal point F ₂ of the reflector 3, passes through the projection lens 4, and is irradiated forward of the vehicle.

At that time, a portion of the reflected light from the reflector 3, the rear shade 6 and is blocked by the front shade 5, cut the light-dark boundary forming portion 6A of the rear shade 6 offline light distribution L ₂ is also a front shade cut-off line light distribution L ₁ is formed by the fifth light-dark boundary forming portion 5A.

The cut off line light distribution L ₁ which is formed by the front shade 5, a cut-off line light distribution L ₂ formed by the rear shade 6 are combined, as shown in FIG. 5 in front of the vehicle, cut into the upper edge offline A low beam light distribution pattern PL for passing which has CL is formed.

At this time, in the right portion and a front view of the light-dark boundary forming portion 5A of the front shade 5, a light-dark boundary forming portion 6A of the rear shade 6, the right side of the right edge 5A ₂ is rear shade 6 of the front shade 5 It is formed higher than the edge 6A _2.

Therefore, as shown in FIG. 1, the reflected light that intersects the plane including the optical axis X on the rear side from the second focal point F ₂ toward the right edge 6A ₂ of the rear shade 6 from the lower side of the reflector 3. With respect to the cut-off line light distribution L ₂ formed in the above, from the upper side of the reflector 3 toward the right edge 5 A ₂ of the front shade 5, intersects the plane including the optical axis X on the front side of the second focal point F _2. cut-off line light distribution L ₁ formed by the reflected light so deviated downward.

As a result, the two cut-off line light distributions L ₁ and L _{2 that} are shifted in the vertical direction are combined, and the cut-off line CL is placed on the opposite lane side in the light distribution pattern PL shown in FIG. Region CLa is formed.

On the other hand, between the front shade 5 and the rear shade 6, as shown in FIGS. 3 and 4, part of the reflected light from above the reflector 3 enters the second focal point F ₂ .

  The incident reflected light travels downward while being reflected by the opposing reflecting surfaces 8 and 9 of the front shade 5 and the rear shade 6.

Here, the left edge 5A ₃ in dark boundary forming portion 5A of the front shade 5, with a lower height than the left edge 6A ₃ in dark boundary forming portion 6A of the rear shade 6 to form a reflective light extraction unit 10 Therefore, a part of the light reflected by the reflecting surface 9 of the rear shade 6 enters the projection lens 4 from the reflected light extraction unit 10.

Accordingly, the own lane side in the cutoff line CL of the light distribution pattern PL is on the cutoff line CL, reflected light is taken out from the reflected light extraction unit 10 is irradiated as an additional light L _3.

As a result, the own lane side in the cutoff line CL of the light distribution pattern PL, a region CLb which is brightness difference blurred the cut-off line CL is alleviated by this additional light L ₃ are formed.

Specifically, the cut is off line CL is determined by the slope position of the illumination, as shown in FIG. 6, difference in brightness between relaxation region CLb by additional light L _3, illuminance gradient by adding light L ₃ is alpha _2, and the additional The gradient is gentler than the illuminance gradient α ₁ when there is no light L ₃ .

Further, the reflective surface 9 of the rear shade 6, the reflective surface 8 of the front shade 5, or both the reflective surfaces 8, 9 are subjected to surface treatment or painting to adjust the reflectance, and the illuminance gradient α ₂ is adjusted. Thus, the sharpness of the cut-off line CL can be arbitrarily and easily controlled.

As described above, according to the headlamp 1 of the present embodiment, the heights of the light / dark boundary forming portions 5A and 6A of the front shade 5 and the rear shade 6 are different on the opposite lane side in the cut-off line CL of the light distribution pattern PL. Thus, the light / dark difference relaxation region CLa is formed by shifting the two cut-off lines CL formed by the light / dark boundary forming portions 5A and 6A in the vertical direction. On the other hand, the own lane side, brightness difference relaxation region CLb by overlapping additional light L ₃ in cut-off line CL formed in the light-dark boundary forming portion 6A of the rear shade 6 is formed.

  As a result, the cut-off line CL is deceived on the opposite lane side and the own lane side, and for the driver, there is no problem that the amount of light suddenly decreases on the upper side of the cut-off line of the light distribution pattern. It is possible to form an excellent light distribution pattern PL.

In particular, when the light / dark difference relaxation region CLb is formed by the additional light L _3, the illuminance gradient is controlled by adjusting the reflectance of the reflecting surfaces 8 and 9 of the front and rear shades 5 and 6 by surface treatment or the like, thereby cutting The sharpness of the offline CL can be controlled arbitrarily and easily.

  In addition, this invention is not limited to the said embodiment, For example, it can apply also to what does not have a level | step difference in the light-dark boundary formation parts 5A and 6A of the front and back shades 5 and 6, respectively.

In this case, although not shown, in the vicinity of the light-dark boundary forming portion of the front shade 5, by forming a reflected light extraction unit 10 partly provided fenestration, the cut-off line CL by adding light L ₃ A blurred contrast difference region CLb can be obtained.

  Further, the entire light / dark boundary forming part 5 </ b> A of the front shade 5 may be formed higher than the light / dark boundary forming part 6 </ b> A of the rear shade 6.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional explanatory diagram illustrating an optical path state in a vertical cross section of a headlamp according to an embodiment of the present invention. The front view which shows the upper center part of a front and back shade. The perspective view which shows the optical path state in the upper center part of a front and back shade. Sectional drawing which follows the AA line of FIG. Explanatory drawing which shows the light distribution pattern formed on the virtual vertical screen arrange | positioned ahead of a vehicle. Explanatory drawing which shows the cross-sectional illuminance in the BB line of FIG.

Explanation of symbols

1 Headlamp (vehicle lamp)
2 Light source 3 Reflector 4 Projection lens 5 Front shade 5A Bright / dark boundary forming portion 6 Rear shade 6A Bright / dark boundary forming portion 8 Reflecting surface of front shade 9 Reflecting surface of rear shade 10 Reflected light extraction portion PL Light distribution pattern CL Cut-off line

Claims (2)

A projection lens having an optical axis extending in the front-rear direction of the vehicle, a light source disposed on the optical axis behind the projection lens, and arranged around the light source so as to reflect light from the light source toward the projection lens A reflector that is disposed between the projection lens and the reflector, and two shades before and after forming a predetermined light distribution pattern by blocking a part of the reflected light from the reflector,
In the vehicular lamp that forms the cut-off line of the light distribution pattern by the light / dark boundary forming portion provided at the upper ends of the two shades,
Wherein at least a portion of the light-dark boundary forming portion of the front shade of the projection lens side, both when being formed at different heights from the height of the light-dark boundary forming portion on the side shade after the reflector side,
Reflective surfaces are formed on the inner surfaces of the front and rear shades facing each other,
A reflected light extraction part is partially formed on the front shade,
A part of the reflected light from the reflector, the light incident between the front and rear shade light / dark boundary forming portions is reflected by the opposing reflective surfaces, and the light reflected by the rear shade reflective surface is reflected. A vehicular lamp characterized by being irradiated from the light extraction portion to the vicinity of the cut-off line of the light distribution pattern . 2. The vehicular lamp according to claim 1 , wherein the light-dark boundary forming portion of the front shade is partially formed lower than the boundary forming portion of the rear shade to be a reflected light extraction portion .

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