JP2008066185A - Vehicle headlight - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle headlight enabled to give a light distribution for overhead sign in a simple structure without lowering light flux of a main light distribution part. <P>SOLUTION: The vehicle headlight 10, includes a light source 11, and a reflector 12 having a reflecting face of a paraboloid system concave toward front of a light irradiation direction so as to reflect light from the light source toward front of the light irradiation direction. The headlight is so structured that an erected wall face 12c around the reflecting face of the reflector is to have a reflective part 12d for the light distribution for overhead sign reflecting direct light from the light source upward of a horizontal line in front of the light irradiation direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle headlamp used, for example, as a headlamp or an auxiliary headlamp provided at the front of an automobile.

  Conventionally, such a vehicle headlamp is configured, for example, as shown in FIG. That is, in FIG. 6, the vehicle headlamp 1 includes a bulb 2 as a so-called two-lamp type light source and a reflector 3.

The bulb 2 is a bulb generally used for an automobile headlamp or an auxiliary headlamp. In the case shown in the figure, a double filament type bulb for both a traveling beam and a passing beam is used, and its optical axis is used. O is arranged substantially horizontally toward the front in the light irradiation direction, is fixed and held by the socket 2a, and is supplied with power.
Here, the bulb 2 is arranged so that the main beam line 2b for the traveling beam and the sub-line 2c for the low beam, which are the light emitting portions, respectively extend along the optical axis O.

The reflector 3 is formed in a concave shape so as to reflect the light from the bulb 2 forward in the light irradiation direction, and is disposed so that its focal point is located in the vicinity of the light emitting portion of the bulb 2. It is composed of a reflecting surface of a parabolic system.
Here, the parabolic reflecting surface includes not only a rotating parabolic surface but also a free curved surface based on a parabolic surface.

  As shown in FIG. 7, the reflecting surface of the reflector 3 is arranged such that the region 3a above the optical axis O gives a passing beam light distribution pattern, and the region 3b below the optical axis O has a traveling beam distribution pattern. It is formed so as to give a light pattern, that is, the focal point of the region 3a is located near the sub-line 2c of the bulb 2 and the focal point of the region 3b is located near the main line 2b of the bulb 2.

As shown in FIG. 7, the reflector 3 has a standing wall surface 3c having a shape approximating the shape of the parabolic system of the reflecting surface on the outer periphery of the reflecting surface regions 3a and 3b. .
Here, when the standing wall surface 3c reflects light from the bulb 2, the reflected light becomes dazzling light for oncoming vehicles and pedestrians and affects the light distribution standard. Etc. are provided. As a result, the reflected light is diffused. A hood may be used as necessary.

  In particular, in order to block the dazzling light reflected by the standing wall 3c and the reflecting surface area 3b during the passing beam, it is directly adjacent to the standing wall 3c as shown in FIG. There is a shade 2d that blocks light incident on the.

  According to the vehicle headlamp 1 having such a configuration, the bulb 2 is supplied with power from the outside via the socket 2a. For this reason, the main line 2b or the subline 2c emits light. Thereby, the light emitted from the bulb 2 is reflected by the reflecting surface of the reflector 3 to become substantially parallel light, and is irradiated forward in the light irradiation direction.

  At this time, when the secondary line 2b of the bulb 2 emits light, as shown in FIG. 6, a part of the light emitted from the secondary line 2b of the bulb 2 is blocked by the shade 2d. As a result, the light is incident only on the region 3a of the reflector 3 and reflected by the region 3a, thereby forming a light distribution pattern (main light distribution portion) A of a low beam as shown in FIG. On the other hand, when the main line 2a of the bulb 2 emits light, as shown in FIG. 9, the light emitted from the main line 2a of the bulb 2 enters the areas 3a and 3b of the reflector and is reflected by the areas 3a and 3b. To do. Thereby, a light distribution pattern (not shown) of the traveling beam is formed.

By the way, in recent standards for vehicle headlamps, in order to visually recognize road signs and the like installed on the road, in the light distribution pattern of FIG. On the upper side, a so-called overhead sign light distribution B has been adopted.
The range and illuminance of the light distribution for overhead sign are determined by the light distribution standard.

When such overhead sign light distribution corresponds to the vehicle headlamp 1 described above, as shown in FIG. 7, a reflection portion for light distribution for overhead sign is provided in the area 3 a of the reflection surface of the reflector 3. It is necessary to provide 3d and 3e.
Thereby, the light from the main line 2a or the sub-line 2b of the bulb 2 is reflected by these reflection portions 3d and 3e to form an overhead sign light distribution slightly above the horizontal line ahead in the light irradiation direction.

  By the way, the reflection parts 3d and 3e for the overhead sign light distribution in the vehicle headlamp 1 described above are provided in the region 3a which is the reflection surface for the low beam of the reflector 3. For this reason, the light flux forming the low beam is reduced, and the illuminance of the light distribution pattern of the low beam is reduced.

Further, the reflection portions 3d and 3e for the overhead sign light distribution in the vehicle headlamp 1 described above have different curvatures and angles from the region 3a of the reflector 3. For this reason, a level | step difference will arise between the surrounding area | regions 3a.
Here, the reflector 3 is generally made of, for example, a so-called BMC (Bulk Molding Compound) made of a thermosetting unsaturated polyester or a steel plate, and has an undercoat and a metal vapor deposition film as a reflecting surface on the surface thereof. Is formed.

  However, as described above, if there is a step at the periphery of the reflecting portions 3d and 3e, the undercoat material accumulates at the step when the undercoat is applied. Therefore, when the vehicle headlamp is completed, the light emitted from the bulb 2 is scattered when it enters this portion, and becomes dazzling light to an oncoming vehicle or the like. In addition, the light distribution standard cannot be satisfied.

  Furthermore, in recent years, with the miniaturization of vehicle headlamps, the reflecting surface itself has also become smaller, and a part of the reflecting surface used for forming the light distribution pattern is part of the overhead sign light distribution. For this reason, the luminous flux of the main light distribution portion A in the light distribution pattern is reduced, and the illuminance is lowered. Moreover, the freedom degree of the light distribution control will become small.

  In view of the above, an object of the present invention is to provide a vehicle headlamp that provides light distribution for overhead sign without reducing the luminous flux of the main light distribution section with a simple configuration.

  According to the present invention, the above object is directed toward the front of the light source and the light irradiation direction arranged so that the focal position is located in the vicinity of the light source so as to reflect the light from the light source toward the front of the light irradiation direction. And a reflector having a concave parabolic reflecting surface, wherein the standing wall around the reflecting surface of the reflector is above the horizontal line ahead of the light irradiation direction of the direct light from the light source. It is achieved by a vehicle headlamp, characterized in that it has a reflective part for light distribution for overhead sign that reflects against the light.

  In the vehicle headlamp according to the present invention, preferably, the standing wall surface of the reflector is formed without a step with respect to the reflecting surface.

  In the vehicle headlamp according to the present invention, preferably, the standing wall surface of the reflector includes a diffusing portion for diffusing reflected light in a region excluding the reflecting portion.

  According to the said structure, the light which radiate | emitted from the light source and entered into the reflective surface of a reflector reflects on this reflective surface, and is irradiated toward the light irradiation direction front. As a result, a light distribution pattern of a passing beam or a traveling beam is formed based on the shape of the reflecting surface.

In addition, the light incident on the reflection part for overhead sign light distribution provided on the vertical wall of the reflector from the light source is reflected by this reflection part and is used for the overhead sign slightly above the horizontal line in front of the light irradiation direction. Form a light distribution.
Thereby, the light distribution for overhead signs is irradiated to the road sign etc. which are located a little above the horizon with respect to the traveling direction of the automobile, for example. For this reason, these road signs etc. are illuminated brightly, and these road signs etc. can be visually recognized reliably.

In that case, the reflection part for the overhead sign light distribution is provided on the standing wall surface of the reflector from which the light directly incident from the conventional light source is reflected as dazzling light. Thereby, the dazzling light reflected by this area | region is reduced.
Further, conventionally, light that has not been used for forming the main light distribution portion can be used as the overhead sign light distribution. For this reason, the utilization efficiency of the light from a light source improves. In addition, the light flux reflected by the reflecting surface of the reflector and applied to the main light distribution unit is not reduced.

Therefore, even if a reflection portion for light distribution for overhead sign is provided, light from the reflection surface of the reflector can be used effectively, and the light distribution standard is not satisfied.
Further, the reflection part for the overhead sign light distribution does not affect the main light distribution part as described above. For this reason, an area and a shape can be arbitrarily set as needed.

  When the standing wall surface of the reflector is formed without a step with respect to the reflecting surface, the undercoat material is reflected from the standing wall surface when the reflecting surface is formed by applying an undercoat to the inner surface of the reflector. There is no accumulation at the step at the boundary with the surface. Accordingly, scattering due to the undercoat material accumulated in the steps is eliminated. As a result, the oncoming vehicle or the like is not dazzled, or the light distribution standard is not satisfied.

  In the case where the standing wall surface of the reflector includes a diffusing portion for diffusing reflected light in a region excluding the reflecting portion, light directly incident on the standing wall from the light source excludes the reflecting portion. When the light is reflected at the region, it is diffused by the diffusion unit. Thereby, the dazzling light with respect to an oncoming vehicle, a pedestrian, etc. can be reduced.

  A hood is provided so as to block light incident on at least the standing wall surface of the reflector directly from the light source, and the hood allows the light directed to the reflection portion for the overhead sign light distribution to pass therethrough. Is provided, the light directed from the light source directly toward the standing wall of the reflector is blocked by the hood. As a result, the reflected light from the standing wall does not become dazzling light, and the light that has passed through the through hole of the hood is reflected by the reflection part for the overhead sign light distribution, and is used for the overhead sign. A light distribution will be formed.

  In this way, according to the present invention, the reflecting portion for the light distribution for the overhead sign is provided on the standing wall surface located outside the reflecting surface of the reflector. Thereby, the overhead sign light distribution can be obtained without reducing the luminous flux of the main light distribution unit and without giving dazzling light.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. As long as there is no description of the effect, it is not restricted to these aspects.

[Example 1]
FIG. 1 shows the configuration of an embodiment of a vehicle headlamp according to the present invention.
In FIG. 1, a vehicle headlamp 10 is configured as a two-lamp headlamp of an automobile, and includes a bulb 11 as a light source, and a reflector 12 that reflects light from the bulb 11 forward in the light irradiation direction. , Is composed of.

The bulb 11 is a bulb generally used for an automobile headlamp or an auxiliary headlamp. In the case shown in the figure, a double filament type bulb for both a traveling beam and a passing beam is used, and its optical axis is used. O is arranged substantially horizontally toward the front in the light irradiation direction, is fixedly held by the socket 11a, and is supplied with power.
Here, the bulb 11 is arranged such that the traveling beam main line 11b and the passing beam sub-line 11c, which are the light emitting portions, extend along the optical axis O, respectively.

The reflector 12 is formed in a concave shape so as to reflect the light from the bulb 11 forward in the light irradiation direction, and is disposed so that its focal point is located near the light emitting portion of the bulb 11. It is composed of a reflecting surface of a parabolic system.
Here, the paraboloidal reflecting surface includes not only a rotating paraboloid but also a free-form surface based on a paraboloid.

  As shown in FIGS. 2 and 3, the reflecting surface of the reflector 12 is formed so that the region 12a above the optical axis O gives a passing beam light distribution pattern, and the region 12b below the optical axis O. Form a traveling beam light distribution pattern, that is, the focal point F of the region 12a is located near the sub-line 11c of the bulb 11, and the focal point of the region 12b is located near the main line 11b of the bulb 11. Has been.

Further, the reflector 12 has a standing wall surface 12c having a shape approximating the shape of the paraboloidal system of the reflecting surface on the outer periphery of the reflecting surface regions 12a and 12b. A reflection portion 12d for overhead sign light distribution is provided adjacent to the region 12a.
The reflecting portion 12d reflects light that is directly incident from the sub-line 11c of the bulb 11, and irradiates light slightly above the horizontal line near the center in the front of the light irradiation direction, so-called overhead sign light distribution. It comes to form.
The reflection portion 12d can be selected with respect to its size and shape so as to obtain an optimum illuminance of the overhead sign light distribution according to the light emission amount of the bulb 11.

Here, when reflecting the light from the bulb 11, the standing wall 12 c has a reflection portion 12 d for the overhead sign light distribution so that the reflected light does not become dazzling light for an oncoming vehicle or a pedestrian. A diffused portion (not shown) or a hood for diffusing reflected light is provided in the entire excluded area.
Such a diffusing section is configured by a shape that reflects and diffuses incident light such as knurls and wrinkles.

  The vehicle headlamp 10 according to the embodiment of the present invention is configured as described above, and the main line 11b or the sub line 11c emits light when the bulb 11 is externally supplied with power through the socket 11a. Thereby, the light emitted from the bulb 11 is reflected by the reflecting surface of the reflector 12 to become substantially parallel light and is irradiated forward in the light irradiation direction.

  At that time, when the sub-line 11c of the bulb 11 emits light, as shown in FIG. 1, a part of the light emitted from the sub-line 11c of the bulb 11 is blocked by the shade 11d. 4a and is reflected by the region 12a to form a light distribution pattern (main light distribution portion) A of a low beam as shown in FIG.

Of the light emitted from the sub-line 11c, the light directly incident on the reflection portion 12d for overhead sign light distribution on the standing wall surface 12c of the reflector 12 is forward in the light irradiation direction as shown in FIG. The overhead sign light distribution pattern B slightly above the horizontal line is formed.
Thereby, the light distribution for overhead signs is irradiated to the road sign etc. which are located a little above the horizon with respect to the traveling direction of the automobile, for example.
Therefore, these road signs and the like are illuminated brightly, and these road signs and the like can be surely visually recognized.

  On the other hand, when the main line 11b of the bulb 11 emits light, the light emitted from the main line 11b of the bulb 11 enters the regions 12a and 12b of the reflecting surface 12 and is reflected by the regions 12a and 12b. Thereby, the light distribution pattern of the traveling beam is formed.

In this case, the reflection portion 12d reflects light that has not been used for forming the main light distribution portion A as overhead light distribution. For this reason, the utilization efficiency of the light from the bulb 11 is improved. Further, the light beam irradiated to the main light distribution portion in the low beam is not reduced by the installation of the reflection portion 12d.
Therefore, the light flux of the main light distribution unit does not decrease the illuminance of the main light distribution unit and the light distribution standard is not satisfied, and the passing beam having the main light distribution unit that satisfies the light distribution standard A light distribution pattern for use will be obtained.
Moreover, since the reflected light by the standing wall surface 12c was conventionally dazzling light, a part of reflected light of the standing wall surface 12c is utilized as light distribution for overhead signs. Thereby, such dazzling light is also reduced.

  Furthermore, the boundary between the standing wall surface 12c and the reflective surface regions 12a and 12b can be formed without a step. For this reason, the undercoat material at the time of manufacture of the reflector 12 does not accumulate at the step at this boundary, and scattering by the undercoat material accumulated at the step can be eliminated.

[Example 2]
FIG. 5 shows a configuration of a main part of a second embodiment of the vehicle headlamp according to the present invention.
In FIG. 5, the vehicle headlamp 20 has substantially the same configuration as the vehicle headlamp 10 shown in FIG. 1, and therefore the same components are denoted by the same reference numerals and description thereof is omitted.
Compared to the vehicle headlamp 10 shown in FIG. 1, the vehicle headlamp 20 includes three reflecting portions 21 that are divided from each other instead of the reflecting portion 12 d provided on the standing wall surface 12 c of the reflector 12. It is a structure which is different only in the point.
The reflective portions 21 have, for example, elongated shapes, and are arranged side by side. The reflective portion 21 may have any surface shape.

  According to the vehicle headlamp 20 having such a configuration, the light that directly acts on each reflecting portion 21 from the auxiliary line 11c of the bulb 11 acts in the same manner as the vehicle headlamp 10 shown in FIG. Reflected by each reflecting portion 21 and irradiated forward in the light irradiation direction, an overhead sign light distribution pattern B slightly above the horizontal line in front of the light irradiation direction is formed.

In the embodiment described above, the vehicle headlamp 10 is provided with the shade 11d. However, the present invention is not limited to this, and the shade 11d may be omitted. In this case, the light incident on the standing wall surface 12c of the reflector 12 is diffused and reflected by the diffusion portion. Thereby, it does not give dazzling light to an oncoming vehicle or a pedestrian.
Further, the shade 11d may be left as it is, and the diffusion portion of the standing wall surface 12c may be omitted. In this case, light that directly enters the standing wall surface 12c from the auxiliary line 11c of the bulb 11 is blocked by the shade 11d. For this reason, the light reflected by the standing wall surface 12c does not become dazzling light.

In the above-described embodiment, the vehicle headlamps 10 and 20 include the reflecting portion 12d or 21 on the standing wall 12c of the reflector 12 in order to form the overhead sign light distribution B. The reflection part for the light distribution for sign does not need to be the size and shape of these reflection parts 12d, 21 and is based on the light emission intensity of the bulb 11 so as to satisfy the light distribution standard of the light distribution for overhead sign. Thus, an appropriate size and shape can be selected.
At this time, since the reflection portion does not affect the light flux forming the main light distribution portion A, the reflection portion for the overhead sign light distribution has an arbitrary size and shape within the range of the standing wall surface 12c. Is possible.

Furthermore, in the above-described embodiment, the vehicle headlamps 10 and 20 are configured as a two-lamp headlamp that serves as a passing beam and a traveling beam by using a double filament type bulb 11 as the bulb 11. However, the present invention is not limited to this, and it may be configured as a headlamp dedicated to a passing beam used for a so-called four-lamp headlamp.
In the above-described embodiments, the case where the vehicle headlamp 10 is a headlamp has been described. However, the present invention is not limited to this, and the vehicle headlamp 10 is configured as another type of vehicle headlamp, for example, an auxiliary headlamp such as a fog lamp. It is also possible.

  In this way, according to the present invention, an extremely excellent vehicle headlamp can be provided that provides light distribution for overhead signing with a simple configuration without reducing the luminous flux of the main light distribution section. It will be.

It is a schematic longitudinal cross-sectional view which shows the structure of 1st embodiment of the vehicle headlamp by this invention. It is a schematic front view which shows the reflector in the vehicle headlamp of FIG. FIG. 3 is a schematic cross-sectional view of the reflector of FIG. 2. It is a graph which shows the light distribution pattern of the passing beam in the vehicle headlamp of FIG. It is a schematic front view of the reflector in 2nd embodiment of the vehicle headlamp by this invention. It is a schematic longitudinal cross-sectional view which shows the structure of an example of the conventional vehicle headlamp. It is a schematic front view which shows the reflector in the vehicle headlamp of FIG. It is a graph which shows the light distribution pattern of the passing beam by the vehicle headlamp of FIG. It is a schematic longitudinal cross-sectional view which shows the light irradiation state at the time of the traveling beam in the vehicle headlamp of FIG.

Explanation of symbols

10, 20 Vehicle headlamp 11 Bulb (light source)
11a Socket 11b Main line 11c Sub line 11d Shade 12 Reflector 12a, 12b Area 12c Standing wall surface 12d, 21 Reflection portion for light distribution for overhead sign

Claims (4)

A light source;
A reflector having a concave paraboloidal reflection surface arranged forwardly in the light irradiation direction, so that the focal point is positioned in the vicinity of the light source so as to reflect light from the light source forward in the light irradiation direction; ,
In a vehicle headlamp comprising:
The standing wall surface around the reflection surface of the reflector has a reflection portion for light distribution for overhead sign that reflects direct light from the light source upward from a horizontal line in front of the light irradiation direction.
A vehicle headlamp characterized by that.   The vehicle headlamp according to claim 1, wherein the standing wall surface of the reflector is formed without a step with respect to the reflecting surface.   The vehicle headlamp according to claim 1, wherein the standing wall surface of the reflector includes a diffusing portion for diffusing reflected light in a region excluding the reflecting portion. A hood arranged adjacent to the light source so as to block light incident on at least the standing wall of the reflector directly from the light source;
This hood is provided with a through hole through which light directed to the reflection portion for the overhead sign light distribution can pass.
The vehicle headlamp according to any one of claims 1 to 3, wherein

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