JP5168550B2 - Vehicle headlamp - Google Patents

Description

  The present invention relates to a vehicular headlamp, and more particularly to a vehicular headlamp that can satisfy a brightness standard in an upper region of a predetermined light distribution pattern.

  Conventionally, in a vehicle headlamp that reflects a light emitted from a light source (hereinafter referred to as a bulb) such as an incandescent bulb or a discharge bulb toward the front of the vehicle by a reflector, and forms a predetermined light distribution pattern, the cause of glare In order to block the direct light from the bulb, a light shielding hood is known in the vicinity of the front side end of the bulb (see, for example, Patent Literature 1 and Patent Literature 2).

  This shading hood can take various forms in relation to vehicle design or the like (eg, reflector design).

For example, in Patent Document 1, a frustoconical light shielding hood having a reflective film formed on the surface by vapor deposition or painting is used. In Patent Literature 2, a light shielding hood having a cylindrical shape, a polygonal column shape, a tapered cylindrical shape, or a polygonal column shape is used.
Japanese Patent Laid-Open No. 09-17206 JP 11-260114 A

  However, in relation to the vehicle design, etc., for example, when a light-shielding hood having a tapered surface with a mirror surface formed on the surface by vapor deposition or painting is used as the light-shielding hood, depending on the degree of taper, As shown in FIG. 12, the upper surface of the mirror surface formed on the light shielding hood reflects the reflected light from the reflector toward the upper region (zone III shown in FIG. 13) of the predetermined light distribution pattern. For this reason, there is a problem that the brightness standard in the zone III (for example, 625 Cd or less when a halogen light bulb is used as a light source) is not satisfied.

  This invention is made | formed in view of such a situation, and it aims at providing the vehicle headlamp which can satisfy the brightness | luminance specification in the area | region of the upper side of a predetermined light distribution pattern.

In order to solve the above-described problem, a vehicle headlamp according to claim 1 includes a bulb, a reflector that reflects light emitted from the bulb forward, and forms a predetermined light distribution pattern, and glare prevention. for the disposed to cover the valve in the lamp front view the front end portion of the valve, the hood having a top surface, the vehicle headlamp having the upper surface of the hood is at least A plurality of irregularities are provided in part by mesh processing or dimple processing for suppressing the intensity of reflected light from the reflector that is reflected toward the region above the horizontal line of the predetermined light distribution pattern , The front side edge of the upper surface is formed in a straight line or a curve, the rear side edge is formed in a curve, and the front side edge between the front side edge and the back side edge of the upper surface of the light shielding hood From back Characterized in that it is formed as a concave conical surface or a curved surface that the curvature radius becomes gradually larger toward the side edges.

  According to the vehicle headlamp according to claim 1, the light shielding hood (surface that reflects the reflected light from the reflector toward the upper region (zone III shown in FIG. 13) of the predetermined light distribution pattern). At least a part of is subjected to processing for suppressing the intensity of reflected light from the reflector that is reflected toward the upper region of the predetermined light distribution pattern. For this reason, it is possible to suppress the intensity of the reflected light from the reflector that is reflected toward the upper region (zone III shown in FIG. 13) of the predetermined light distribution pattern.

  Therefore, according to the vehicle headlamp described in claim 1, it is possible to satisfy the brightness standard in the upper region of the predetermined light distribution pattern.

According to the vehicle headlamp according to claim 1 , a part of the reflected light from the reflector is diffused or scattered by the plurality of irregularities formed on the upper surface of the reflector. It becomes possible to reduce the light quantity (intensity) of the reflected light reflected toward the region (zone III shown in FIG. 13).

Further, according to the vehicle headlamp described in claim 1 , by adjusting the number of the plurality of irregularities formed on the upper surface, toward the upper region (zone III shown in FIG. 13) of the predetermined light distribution pattern. It is possible to adjust the light amount (intensity) of the reflected light reflected to the desired light amount (intensity).

Therefore, according to the vehicle headlamp described in claim 1 , it is possible to satisfy the brightness standard in the upper region of the predetermined light distribution pattern.
For example, when the light shielding hood has an N truncated pyramid shape, the entire surface of one of the N isosceles bases constituting the N truncated pyramid shape is processed into a truncated cone shape or a spherical shape. When the top surface is used, both the front side edge and the back side edge of the side surface of the one isosceles base are curved, whereas the front side edge and the back side edge of the remaining side surface of the isosceles base are curved. Both become straight lines. For this reason, there exists a problem that it is hard to be visually recognized as an N-pyramidal frustum shape on the appearance, and the appearance is not stable.
According to claim 1, this problem can be solved. That is, according to the first aspect of the present invention, the front side edge is formed into a straight line and the back side end edge is formed into a curved line, and the space between the straight line and the curved line extends from the front side edge to the back side. Since the upper surface formed as a concave curved surface with a gradually increasing radius of curvature toward the side edge is adopted, the appearance should have a stable appearance that can be visually recognized as an N pyramid shape at first glance. Is possible. In addition, it is possible to reduce or almost eliminate the light amount (intensity) of the reflected light from the reflector that is reflected toward the upper region (zone III shown in FIG. 13) of the predetermined light distribution pattern.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the vehicle headlamp which can satisfy the brightness | luminance specification in the area | region of the upper side of a predetermined light distribution pattern.

  Hereinafter, a vehicle headlamp according to the present invention will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a perspective view of a main part of a vehicle headlamp 100 according to the present embodiment. FIG. 2 is a cross-sectional view of a main part of the vehicle headlamp 100. The vehicle headlamp 100 is configured as an automobile headlamp, and mainly includes a bulb 10, a reflector 20, a hood 30, and a cover lens 40.

  The bulb 10 is a light source such as an incandescent bulb or a discharge bulb, and is, for example, a bulb of a predetermined standard (for example, a standard called HB2).

  The reflector 20 is a multi-reflector in which a large number of parabolic column surfaces are arranged side by side on the surface, and a predetermined light distribution pattern is formed by reflecting light emitted from the bulb 10 forward. The reflector 20 is formed by injection-molding a resin material such as ABS or BMC, and then performing a mirror surface treatment by vapor deposition of aluminum or the like. The front surface of the reflector 20 is covered with a cover lens 40.

  As shown in FIG. 3, the hood 30 includes a hood top 31 that shields light directly irradiated from the bulb 10 in order to prevent glare, and a hood stay 32 that supports the hood top 31 on the reflector 20. Composed. The hood top 31 is provided near the front side of the tip of the valve 10 so as to cover the tip of the valve 10. Hereinafter, the food top 31 will be described.

  FIG. 4 is a front perspective view of the hood top 31. The food top 31 includes a hollow octagonal pyramid shaped part 31a and an octagonal pyramidal part 31b.

  On the front side of the octagonal frustum-shaped portion 31a, a hollow octagonal pyramidal portion 31b having a different side surface inclination angle from the octagonal frustum-shaped portion 31a is integrally formed. Accordingly, the hood top 31 is formed in a substantially pyramid-shaped cylindrical shape whose end face on the front side is covered. The food top 31 is formed of a plate material of iron (for example, SPC material). The entire outer surface of the hood top 31 is mirror-finished by, for example, chrome plating, vapor deposition, or painting.

  The octagonal frustum-shaped portion 31a is constituted by eight isosceles trapezoidal side surfaces. A predetermined upper surface 31 a-1 of these eight surfaces is a surface located directly above the valve 10 when the hood top 31 is attached to the reflector 20 as shown in FIG. 2. That is, the hood top 31 is provided on the front side of the valve 10 such that the upper surface 31a-1 is located on the upper side of the valve 10 and is inclined only in the front-rear direction with respect to the horizontal plane.

  On the upper surface 31a-1 located on the upper side of the valve 10, as shown in FIG. The specifications for mesh processing (mesh thickness and interval) and the range for mesh processing are determined so as to satisfy the brightness standard of zone III of the light distribution pattern shown in FIG. For example, the thickness of the mesh is about 0.5 to 1 mm, and the mesh interval is about 1.5 times or less of the mesh thickness.

  The mesh processing range is determined so that, for example, the regular reflection amount on the upper surface 31a-1 is equal to or less than the diffuse reflection amount on the upper surface 31a-1. In the upper surface 31a-1, regular reflection is performed at a portion where the unevenness is not formed, and diffuse reflection is performed at the portion where the unevenness is formed. Therefore, in order to make the regular reflection amount equal to or less than the diffuse reflection amount, mesh processing may be performed so as to form irregularities in a range of half or more of the entire area of the upper surface 31a-1.

  Next, the manufacturing method of the food top 31 is demonstrated. First, a pressing process as shown in FIG. 5 is performed. As shown to Fig.5 (a), the SPC board which is a base is cut | disconnected to a defined shape. Next, as shown in FIG. 5 (b), the cut material is pressed to make the shape of the hood top 31, and as shown in FIG. 5 (c), unnecessary portions of the outer shape are cut. And as shown in FIG.5 (d), an unevenness | corrugation is formed by the mesh process with respect to the surface used as the upper surface 31a-1. When the pressing process is completed, a plating process is performed. Thereby, the food top 31 is completed.

  As described above, according to the vehicle headlamp 100 of the present embodiment, the upper surface 31a-1 formed on the hood 30 (the cut-off line of the predetermined light distribution pattern shown in FIG. 13 is the reflected light from the reflector 20). Reflector that is reflected toward the upper region (zone III shown in FIG. 13) of the predetermined light distribution pattern is provided on at least a part of the upper region (zone III shown in FIG. 13). Processing for suppressing the intensity of reflected light from 20 (a plurality of irregularities by mesh processing) is performed.

  For this reason, a part of the reflected light from the reflector 40 reflected toward the upper region (zone III shown in FIG. 13) of the predetermined light distribution pattern is formed on the upper surface 31a-1 of the reflector 40. Since the light is diffused or scattered by a plurality of irregularities, the amount (intensity) of reflected light from the reflector 40 reflected toward the region above the cutoff line (zone III shown in FIG. 13) of the predetermined light distribution pattern is reduced. Is possible.

  Therefore, according to the vehicle headlamp 100 of the present embodiment, it is possible to satisfy the brightness standard in the region above the cut-off line of the predetermined light distribution pattern (zone III shown in FIG. 13).

  Moreover, according to the vehicle headlamp 100 of the present embodiment, by adjusting the number of the plurality of irregularities formed on the upper surface 31a-1 of the reflector 40, the region above the cut-off line of the predetermined light distribution pattern (FIG. 13). It is possible to adjust the amount of light (intensity) of the reflected light from the reflector 40 reflected toward the zone III) shown in FIG.

  In this embodiment, the unevenness is formed by performing mesh processing on the upper surface 31a-1, but as shown in FIG. 6, the unevenness may be formed on the upper surface 31a-1 'by dimple processing. . The dimple processing specifications (hole diameter and depth) and the dimple processing range are also determined so as to satisfy the brightness standard of the zone III of the light distribution pattern, as in the case of mesh processing. For example, the hole diameter is about 2 mm to 10 mm in diameter, and the depth is about 0.4 mm to 0.6 mm. The range of the dimple processing is a range where the regular reflection amount is less than or equal to the diffuse reflection amount, that is, a range where the non-planar area after the dimple processing is more than half of the entire area of the upper surface 31a-1. .

<Second Embodiment>
The first embodiment of the present invention reduces the light irradiated to the zone III of the light distribution pattern by forming irregularities on a predetermined side surface of the octagonal truncated cone portion of the hood top by mesh processing or dimple processing. Although the brightness standard of zone III of the light distribution pattern is satisfied, the method for satisfying the brightness standard of zone III of the light distribution pattern is not limited to this.

  In the second embodiment of the present invention, at least a part of a predetermined side surface of the octagonal truncated pyramid portion of the hood top is formed by a curved surface, thereby reducing the light irradiated to the zone III of the light distribution pattern. It satisfies the brightness standard of the zone III of the light pattern.

  Hereinafter, a vehicle headlamp 200 according to a second embodiment of the present invention will be described with reference to the drawings. The same parts as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 7 is a cross-sectional view of a main part of the vehicle headlamp 200 according to the present embodiment. The vehicular headlamp 200 is configured as a headlamp of an automobile, and mainly includes a bulb 10, a reflector 20, a hood 50, and a cover lens 40.

  The hood 50 includes a hood top 51 that shields light directly irradiated forward from the bulb 10 to prevent glare, and a hood stay 52 that supports the hood top 51 on the reflector 20. The hood top 51 is provided near the front side of the tip of the valve 10 so as to cover the tip of the valve 10. Hereinafter, the food top 51 will be described.

  FIG. 8 is a front perspective view of the hood top 51. The food top 51 includes a hollow octagonal pyramid shaped part 51a and an octagonal pyramidal part 51b.

  The hood top 51 is formed on the front side of the hollow octagonal truncated pyramid 51a by integrally forming a hollow octagonal pyramidal portion 51b having a different side surface inclination angle from the octagonal truncated pyramid 51a. It is a member formed in a cylindrical shape of a substantially truncated pyramid whose end face is covered, and is formed of a plate material of iron (for example, SPC material). The entire outer surface of the hood top 51 is mirror-finished by, for example, chrome plating, vapor deposition, or painting.

  The octagonal truncated pyramid 51a is configured by eight isosceles trapezoidal surfaces. Of the eight side surfaces, the upper surface 51a-1 positioned directly above the bulb 10 is formed by a concave spherical surface having a radius of 50 mm to 60 mm.

  FIG. 9 shows an optical path of light emitted from the bulb 10 when the hood top 51 formed in this way is used. Light that is irradiated almost directly from the bulb 10 and reflected by the reflector 20 is reflected by the hood top 51. However, since the upper surface 51a-1 is a curved surface, the light reflected by the upper surface 51a-1 is not only forward. , Diffused and irradiated in various directions. When the upper surface 51a-1 is formed of a concave spherical surface having a radius of 50 mm to 60 mm, the light irradiated to the zone III of the light distribution pattern is compared with the case where the conventional hood top is used (see FIG. 12). For example, it can be weakened by about 4 times.

  As described above, according to the vehicle headlamp 100 of the present embodiment, at least a part of the upper surface 51a-1 formed on the hood 50 is processed to diffuse the reflected light from the reflector 20. (The upper surface 51a-1 processed into a conical surface or a spherical surface). For this reason, part or all of the reflected light from the reflector 20 is diffused by the upper surface 51a-1 processed into a conical surface or a spherical surface, so that the region above the cutoff line of the predetermined light distribution pattern (see FIG. 13). It is possible to reduce or almost eliminate the amount of light (intensity) of the reflected light from the reflector 20 reflected toward the zone III shown.

  Therefore, according to the vehicle headlamp 100 of the present embodiment, it is possible to satisfy the brightness standard in the region above the cut-off line of the predetermined light distribution pattern.

  In the present embodiment, the upper surface 51a-1 is formed as a concave spherical surface to prevent the front of the hood top 51 from being irradiated with a strong lump of light. The shape of the upper surface 51a-1 that can prevent the lump from being irradiated is not limited to this. Hereinafter, a modification of the second embodiment will be described with reference to FIGS. 10 and 11.

  FIG. 10 shows a hood top 51 ′ of a first modification of the second embodiment. The food top 51 'includes a hollow octagonal pyramid shaped part 51a' and an octagonal pyramidal part 51b.

  The hood top 51 ′ is formed by integrally forming a hollow octagonal pyramid 51b having a different side surface inclination angle from the octagonal pyramidal cone 51a ′ on the front side of the hollow octagonal pyramidal cone 51a ′. The Of the eight side surfaces of the octagonal truncated cone-shaped portion 51a ′, the upper surface 51a′-1 positioned directly above the bulb 10 is at the edge of the front side (the side where the octagonal pyramidal portion 51b ′ is provided). It is formed by a concave conical surface having a curvature radius curve with a radius of curvature of about 30 mm and a curvature radius at the edge on the back side of about 40 mm.

  Since the upper surface 51a′-1 is a curved surface, the light reflected by the upper surface 51a′-1 is diffused and irradiated not only in the front direction but also in various directions. For this reason, the light is reflected by the upper surface 51a′-1, so that a strong lump of light is not irradiated forward. Thereby, the brightness standard in zone III of the light distribution pattern can be satisfied.

  However, when the hood top 51 ′ shown in FIG. 10 is used, there is a problem that the curved surface on the front side is visually recognized when viewed from the front, and the appearance is poor.

  That is, when the hood has an N-pyramidal frustum shape (for example, an octagonal frustum shape), one of the N isosceles frustum side surfaces constituting the N-pyramidal frustum shape has a frustum surface When the upper surface is processed into a spherical shape, both the front edge and the rear edge of the side surface of the one isosceles base are curved, whereas the front side edge of the remaining side surface of the isosceles base is curved. And both of the back side edges are straight. For this reason, there is a problem that the hood is difficult to be visually recognized as an N-pyramidal shape in appearance, and has a stable appearance.

  The form which improved this is the 2nd modification of 2nd Embodiment shown in FIG. This second modification is characterized in that it is formed so that the cross-sectional shape at the front edge is a straight line.

  The food top 51 ″ is formed by a hollow octagonal pyramid-shaped portion 51a ″ and a hollow octagonal pyramid-shaped portion 51b having a different side surface inclination angle from the octagonal pyramid-shaped portion 51a ″. Of the eight side surfaces of the octagonal truncated pyramid 51a ″, the upper surface 51a ″ -1 positioned immediately above the bulb 10 has, for example, a straight edge on the front side and a radius on the rear edge. A curved surface having a curvature radius of about 35 mm is formed, and a concave curved surface is formed between the edge on the front side and the edge on the back side so that the curvature radius gradually increases toward the back side.

  In this way, if the edge on the front side is a straight line and the curved surface gradually increases in radius of curvature in the cross section toward the back side, the appearance when viewed from the front is the same as that of a conventional vehicle headlamp. It can be almost unchanged. Even in this case, since a plane is hardly formed on the upper surface, a strong lump of light is not irradiated forward.

  That is, according to the second modification of the second embodiment, the front side edge is formed into a straight line, the back side end edge is formed into a curved line, and the space between the straight line and the curved line is the front side. Since the upper surface formed as a concave curved surface whose radius of curvature gradually increases from the edge toward the rear edge, the appearance can be visually recognized as an N truncated pyramid shape with a sense of stability. It becomes possible to look good. In addition, it is possible to reduce or almost eliminate the light amount (intensity) of the reflected light from the reflector that is reflected toward the upper region (zone III shown in FIG. 13) of the predetermined light distribution pattern.

  The above embodiment is merely an example in all respects. The present invention is not construed as being limited to these descriptions. For example, in the hood top having the shape shown in the second embodiment and the modification, the unevenness as shown in the first embodiment may be formed on the side surface formed by the curved surface.

  The present invention can be implemented in various other forms without departing from the spirit or main features thereof.

It is a principal part perspective view of the vehicle headlamp 100 of 1st Embodiment. It is a longitudinal cross-sectional view of the said vehicle headlamp 100. FIG. 2 is a front perspective view of a hood 33 of the vehicle headlamp 100. FIG. 2 is a front perspective view of a hood top 31 of the vehicle headlamp 100. FIG. It is a figure explaining the manufacturing process of the said food top 31, (a) shows the material before press processing, (b) shows after press molding, (c) shows after an external shape cut, (d) is It shows after mesh processing. It is a front perspective view of food top 31 'of the modification of 1st Embodiment. It is a longitudinal cross-sectional view of the vehicle headlamp 200 of 2nd Embodiment. 2 is a front perspective view of a hood top 51 of the vehicle headlamp 200. FIG. It is a figure which shows the optical path at the time of using the said vehicle headlamp 200. FIG. It is a front perspective view of food top 51 'of the 1st modification of a 2nd embodiment. It is a front perspective view of food top 51 '' of the 2nd modification of a 2nd embodiment. It is a figure which shows the optical path at the time of using the conventional vehicle headlamp. It is a figure which shows a light distribution pattern.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Bulb, 20 ... Reflector, 30, 50 ... Hood, 40 ... Cover lens, 100, 200 ... Vehicle headlamp,

Claims (1)

A valve,
A reflector that reflects the light emitted by the bulb toward the front and forms a predetermined light distribution pattern;
In order to prevent glare, it is arranged to cover the bulb in the front view of the lamp near the front side end of the bulb, and a light shielding hood having an upper surface,
In vehicle headlamps equipped with
The upper surface of the light shielding hood has at least a part of a plurality of irregularities by mesh processing or dimple processing for suppressing the intensity of reflected light from the reflector that is reflected toward the region above the horizontal line of the predetermined light distribution pattern. is applied, is formed on a straight line or a curve front edge of the upper surface of the light shielding hood, rear side edge is formed in a curved and the front side edge of the upper surface of the hood and the rear side edge A vehicular headlamp characterized by being formed as a concave conical surface or curved surface whose radius of curvature gradually increases from the front side edge toward the back side edge .

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