JP3959587B2 - Vehicle headlamp - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicular lamp, and more specifically, it is possible to realize a headlamp that can increase the ratio of the vertical width and the horizontal width, that is, the aspect ratio higher than that of the prior art, or more than that of the prior art. An object of the present invention is to provide a configuration of a headlamp that can improve the luminous flux utilization factor for the light source.
[0002]
[Prior art]
As a technique employed when forming a conventional vehicle headlamp, a headlamp 90 using a parabolic reflecting surface such as a rotating paraboloid, as shown in FIG. It is known that an elliptical reflecting surface such as a spheroid is used like a headlamp 80 shown in FIG.
[0003]
First, in the headlamp 90 shown in FIG. 7, a parabolic reflecting surface 91 such as a rotating paraboloid having an irradiation direction X as a rotation axis is formed, and an incandescent light bulb is formed near the focal point f of the reflecting surface 91. A light source 92 such as a filament is arranged, and when the light source 92 is arranged in an appropriate front with respect to the focal point f, the upper half of the reflecting surface 91 can obtain downward light. A means for obtaining a passing light distribution by providing a covering hood 92a is conventionally employed.
[0004]
Further, in the headlamp 80 shown in FIG. 8, an elliptical reflecting surface 81 such as a rotation ellipse having a first focal point f1 and a second focal point f2 is adopted, and a light source 82 is disposed at the first focal point f1. The reflected light is converged at the focal point f2. Then, a light shielding plate 83 is provided in the vicinity of the second focal point f2, and a desired light distribution shape is formed by shielding a part of the sectional shape of the converged light. The formed sectional shape is shielded from light. A projection lens 84 having a focal point in the vicinity of the plate 83 projects the image in the irradiation direction X.
[0005]
[Problems to be solved by the invention]
However, in the headlamp having the above-described conventional configuration, light from a light source that emits light in all directions, such as a filament, is reflected in the irradiation direction on the reflecting surface to form a light distribution characteristic. If the width of one of the left and right sides is 70 mm or less, the light flux capture rate of the reflecting surface will be extremely low and the purpose of the headlamp will not be achieved. Therefore, the design of the headlamp is limited by the above values. There is a problem that the degree of freedom is low.
[0006]
Further, the headlamp 90 shown in FIG. 7 and the headlamp 80 shown in FIG. 8 both use the hood 92a or the light shielding plate 83 to form a light distribution characteristic for passing. In recent years, there is a problem that the luminous flux utilization rate in the low light distribution used in most conditions during night driving is low, and sufficient brightness cannot be obtained because it shields about half of the light amount. Has occurred.
[0007]
[Means for Solving the Problems]
As a specific means for solving the above-described conventional problems, the present invention has a focal point that substantially coincides with the position of the light source and is provided in a region centered on this focal point and is formed narrow in the vertical direction. A parabolic first reflecting surface that reflects light in the irradiation direction, and a first focal point that substantially coincides with the position of the light source and a major axis that is substantially perpendicular to the irradiation direction, either above or below the first reflecting surface. The second focal point is set near the outer end of the first reflecting surface, and the light irradiated from the light source to either the upper or lower side of the first reflecting surface is used as the second focal point. A pair of left and right elliptical second reflecting surfaces that reflect and a pair of focal points that are provided outside the first reflecting surface and in the same row as the first reflecting surface and substantially coincide with the second focal point of the second reflecting surface. the second reflecting surface for reflecting the light reflected toward the irradiation direction has, on A third reflecting surface of the parabolic formed narrow in the direction,
The first focal point is substantially coincident with the position of the light source, the major axis is set in a direction substantially perpendicular to the irradiation direction, and the second focal point is provided on the other side of the second reflective surface above and below the first reflective surface . A pair of left and right elliptical fourth reflecting surfaces that are set near the outer end of the three reflecting surfaces and reflect the light emitted from the light source to the other of the second reflecting surfaces to the second reflecting surfaces ; A narrow width in the vertical direction that is provided outside the third reflecting surface and has a focal point that substantially coincides with the second focal point of the fourth reflecting surface and reflects the light reflected by the fourth reflecting surface toward the irradiation direction. And a fifth reflecting surface formed on
Provided is a vehicular headlamp characterized in that a shutter having an opening or a light guide tube surrounded by two or more surfaces is provided in the vicinity of a second focal point of the second reflecting surface and the fourth reflecting surface. This solves the problem.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Below, this invention is demonstrated in detail based on embodiment shown in a figure. 1 and 2 show a first embodiment of a vehicle headlamp 1 according to the present invention. In the present invention, the headlamp 1 includes a light source 2, a first reflecting surface 3, and a second embodiment. The reflecting surface 4, the third reflecting surface 5, the fourth reflecting surface 6, and the fifth reflecting surface 7 are configured as main optical components. Although a lens, a housing, and the like naturally exist, they are not a part of the gist of the present invention, so illustration and description thereof are omitted here.
[0009]
The first reflecting surface 3 is a parabolic reflecting surface such as a rotating paraboloid whose rotational axis coincides with the irradiation direction X, and the light source 2 is provided substantially coincident with its focal point f3. Here, in the present invention, the first reflecting surface 3 is extremely narrow compared to the prior art such as a vertical width of 50 mm or less when the headlamp 1 is mounted on a vehicle. Yes.
[0010]
A second reflecting surface 4 is provided above the first reflecting surface 3 so that the major axis Y is substantially horizontal and orthogonal to the irradiation direction X. In the first embodiment, the second reflecting surface 4 is provided. Each of the reflecting surfaces 4 is a pair having the light source 2 as a first focal point f41 and each having a second focal point f42 on the outside. Incidentally, a shutter 41 or a light guide tube 42 is provided in the vicinity of each of the second focal points f42, which will be described later.
[0011]
In addition, on the left and right outer sides of the first reflecting surface 3, a paraboloid or the like having a second focal point f 42 of the second reflecting surface 4 as a substantially focal point f 5 and a rotation axis substantially parallel to the irradiation direction X, A pair of third reflecting surfaces 5 that are parabolic are provided. Therefore, the light of the light source 2 captured by each of the second reflecting surfaces 4 is directed in the irradiation direction X by the third reflecting surface 5.
[0012]
In addition, in the present invention, a pair of ellipsoidal fourth reflecting surfaces 6 are also provided below the first reflecting surface 3, and the fourth reflecting surfaces 6 are connected to the second reflecting surface 4. Similarly, it has a long axis Y that is substantially horizontal and orthogonal to the irradiation direction X, and has a first focal point f61 in the vicinity of the light source 2.
[0013]
The fourth reflecting surface 6 has the respective second focal points f62 in the vicinity of the outer end of the third reflecting surface 5, and the fourth reflecting surface 6 is further outside the third reflecting surface 5. A pair of fifth reflecting surfaces 7 having a parabolic system such as a rotating paraboloid having a focal point f7 in the vicinity of each of the second focal points f62 and having a rotation axis substantially parallel to the irradiation direction X is provided. . Therefore, the light of the light source 2 captured by each of the fourth reflecting surfaces 6 is also directed in the irradiation direction X by the fifth reflecting surface 7.
[0014]
Further, a shutter 61 or a light guide tube 62 is also provided in the vicinity of the second focal point f 62 of the fourth reflecting surface 6 in the same manner as the second reflecting surface 4. Here, when the shutter (41, 61) or the light guide tube (42, 62) is described, the shutter or the light guide tube reflects light converged on the second focal point (f42, f62) to the third reflection. The position and the cross-sectional shape are adjusted so that the light distribution shape as the headlamp 1 is obtained when the light is reflected by the surface 5 and the fifth reflecting surface 7 in the irradiation direction.
[0015]
FIG. 3 shows an example of the configuration of the shutter 41 provided on the second reflecting surface 4. In the present invention, the shutter 61 is also provided on the fourth reflecting surface 6. Therefore, the description here will be made with the shutter 41 as a representative.
[0016]
The shutter 41 is formed of, for example, a metal plate-like member that has been subjected to an antireflection treatment such as black coating, and is provided with an opening 41a that has a rectangular shape, for example. As described above, the light source of the third reflecting surface 5 is installed in the vicinity of the second focal point f42, blocks light other than the openings (41a, 61a), and uses the light that has passed through the openings 41a. It is what.
[0017]
Accordingly, by appropriately setting the focal point f5 of the third reflecting surface 5 and the position and shape of the opening 41a of the shutter 41, the direction of light emitted from the third reflecting surface 5 in the irradiation direction (for example, downward) ), And a shape (for example, 15 degree leftward rise) can be freely set.
[0018]
The above-described action is used more positively to make the shutter 41 movable. For example, when passing by passing, the opening 41a is positioned above the focal point f5 of the third reflecting surface 5 so that the reflected light is directed downward. When the traveling light distribution is obtained, the opening 41a coincides with the focal point f5 of the third reflecting surface 5 and the reflected light is in the front direction, so that the switching can be performed only by moving the shutter 41.
[0019]
FIG. 4 shows an example of the configuration of the light guide tube 42 that can be used in place of the shutter 41. Like the shutter 41, this light guide tube also has a second reflecting surface, Although it can be provided on both of the four reflecting surfaces 6, the structure is almost the same, so that the description will be made by representing the light guide tube 42 provided on the second reflecting surface 4 as in the case of the shutter. Assumed to be performed.
[0020]
The light guide tube 42 is basically formed in a tubular shape having a rectangular cross section, and preferably has an inner surface subjected to reflection treatment by aluminum vapor deposition or the like. With this configuration, if the second focal point f42 of the second reflecting surface 4 is positioned in the vicinity of the entrance 42a of the light guide tube 42, the light converged on the focal point f42 is reflected inside the light guide plate 42. Is conducted to the outlet 42b while repeating the above, and is emitted from the outlet 42b along the cross-sectional shape.
[0021]
Therefore, by adjusting the length of the light guide tube 42, it is possible to separate the position of the second focal point f42 of the second reflecting surface 4 from the position of the focal point f5 of the third reflecting surface 5, so that the headlight An appropriate degree of freedom is given to the design of the lamp 1. Further, for example, if the side of the inlet 42a is set as a reference and the outlet 42b side is swingable in the vertical direction around the inlet 42a side, the light distribution characteristics can be switched in the same manner as the shutter 41 described above.
[0022]
As a result of trial manufacture and examination by the inventor for forming the present invention, it has been confirmed that the tip shape, inclination, and the like of the outlet 42b are also related to the formation of light distribution characteristics. Further, the second reflecting surface 4 is substantially an upper half of an elliptical surface, and the fourth reflecting surface 6 is a substantially lower half, so that the reflected light has directionality. It has been confirmed that the light guide tube 42 (62) may be only a portion corresponding to the above-described directionality, such as two upper and lower sides.
[0023]
FIG. 5 shows a second embodiment of the present invention. In the first embodiment, the second reflecting surface 4 provided above the first reflecting surface 3 is a third reflecting surface provided outside the first reflecting surface 3. The light is supplied to the reflecting surface 5, and the fourth reflecting surface 6 provided below the first reflecting surface 3 supplies light to the fifth reflecting surface 7 provided further outside the third reflecting surface 5.
[0024]
The present invention is not limited to the above-described configuration. As shown in FIG. 5, the second reflecting surface 4 that supplies light to the third reflecting surface 5 is provided below the first reflecting surface 3, and the fifth reflecting surface 7 is provided. The fourth reflecting surface 6 for supplying light to the first reflecting surface 3 may be provided above the first reflecting surface 3, that is, the first and the second embodiments may be inverted.
[0025]
As described above, according to the present invention, even when the headlamp 1 having a vertical width of 50 mm or less, for example, is required, the second reflecting surface 4 and the fourth reflecting surface 6 The light of the upper and lower portions cut out from the reflecting surface 4 is collected, and the third reflecting surface 5 and the fifth reflecting surface 7 are directed in the irradiation direction, thereby enabling the realization without causing a decrease in light amount. Further, since the first reflecting surface, the third reflecting surface 5 and the fifth reflecting surface 7 are arranged in the horizontal direction, the light emitting area as the headlamp 1 can be sufficient, and visibility from other vehicles can be obtained. There is no reduction.
[0026]
FIG. 6 shows a third embodiment of the present invention. In the development process for forming the present invention, an elliptical reflecting surface having a major axis Y substantially perpendicular to the irradiation direction above and below the light source 2 as described above (for example, It was confirmed that the form of providing the second reflecting surface 4 and the fourth reflecting surface 6) of the first embodiment is excellent in the light flux capturing rate with respect to the light source 2.
[0027]
This third embodiment is performed mainly for the purpose of improving the above-described luminous flux capture rate. In order to achieve this purpose, the headlamp 10 according to the third embodiment has a pair in the previous embodiment. The second reflection surface 14, the third reflection surface 15, the fourth reflection surface 16, and the fifth reflection surface 17 that are provided are each provided as one, and the second reflection surface that is elliptical as a basic configuration. 14 and the fourth reflection surface 16 are provided on either one of the left and right sides of the light source 12 (illustrated in the example shown on the right side), the first reflection surface 13 being a parabolic system, and the third reflection. The surface 15 and the fifth reflecting surface 17 are provided on the opposite side.
[0028]
Further, the second reflecting surface 14 and the fourth reflecting surface 16 are provided with the major axis substantially horizontal in the previous embodiment, whereas in the third embodiment, the second reflecting surface 14 and the fourth reflecting surface 16 are provided. The reflection surface 16 is connected at one end on the first focal side, and the major axis is appropriately inclined to the first reflection surface 13, the third reflection surface 15, and the fifth reflection surface 17 side as appropriate.
[0029]
Each of the second reflecting surface 14 and the fourth reflecting surface 16 is provided with a light shielding plate 14a, 16a along the major axis and having a tip near the second focal point (f142, f162), respectively. Interference with the reflecting surface 13, the third reflecting surface 15, and the fifth reflecting surface 17 is prevented. Further, the side of the light shielding plates 14a, 16a facing the second reflecting surface 14 and the fourth reflecting surface 16 is subjected to a mirror surface treatment, and the light guide tube described in the first embodiment can be obtained. Yes.
[0030]
Further, an appropriate gap is provided in the vicinity of the light source 12 of the light shielding plates 14a and 16a, and a first reflecting surface 13 is provided, for example, in a fan shape in a range where direct light is radiated from the gap. Corresponding to the second focal points of the reflecting surface 14 and the fourth reflecting surface 16, a third reflecting surface 15 and a fifth reflecting surface 17 are provided.
[0031]
At this time, as described above, since the second focal point of the second reflecting surface 14 and the second focal point of the fourth reflecting surface 16 are arranged substantially perpendicularly, the third reflecting surface 15 and the fifth reflecting surface 17 are arranged. Are aligned vertically, that is, vertically. At this time, the end portions on the second focal point (f142, f162) side of the light shielding plates 14a, 16a operate in substantially the same manner as the shutter in the previous embodiment, so that they match the desired light distribution shape. It is preferable to optimize the tip shape.
[0032]
Further, with this configuration, the light shielding plates 14a and 16a are arranged close to each other, and can be formed integrally. Therefore, the light shielding plates 14a and 16a are integrated and located at a position indicated by a point P in the drawing. If the angle is appropriately rotated as the center of rotation, switching between the passing light distribution and the traveling light distribution is possible as described in the previous embodiment.
[0033]
The headlamp 10 having the above-described configuration improves the light flux capturing rate with respect to the light source 12 and can obtain a light distribution without using a hood, a light shielding plate, etc., which are essential in the conventional example. It was confirmed by the inventors that the luminous flux utilization rate for 12 reaches approximately 60%. Therefore, when compared with the headlamp having a luminous flux utilization rate of not more than 30% in the conventional example, the headlamp 10 of the third embodiment has twice or more brightness even with the light source 12 having the same power consumption. Will be obtained.
[0034]
In the configuration of FIG. 6, the aspect ratio is not so large as in the embodiment shown in FIGS. 1, 2 and 5, and is the same as that of a conventional vehicle headlamp. However, by implementing the present invention, the light source 12 can be installed close to either the left or right side of the vehicle headlamp 10.
[0035]
Here, in recent automobile designs, overhangs tend to be cut off for the purpose of reducing weight, improving ride comfort, improving maneuverability, etc., and tires move forward in the situation seen from headlights 1 and 10 And it has become a place where you have a place.
[0036]
In the configuration of the vehicle headlamp 10 of the present invention shown in the third embodiment (FIG. 6) of the present invention, the light source 12 is biased to one side and does not interfere with the tire, and the tire Since there are only reflecting surfaces such as a third reflecting surface and a fourth reflecting surface in front of the lens, it is possible to achieve extremely good compatibility with the above-mentioned recent automobile designs.
[0037]
【The invention's effect】
As described above, according to the present invention, the first reflecting surface of the parabolic system that has a focal point that substantially coincides with the position of the light source and reflects light toward the irradiation direction, and the first focal point substantially coincides with the position of the light source. The major axis is a direction substantially orthogonal to the irradiation direction, and substantially coincides with the second focal point of at least one elliptical second reflecting surface provided on either the upper or lower side of the first reflecting surface and the second focal point of the second reflecting surface. A parabolic third reflecting surface having a focal point that reflects light in the irradiation direction, and the first focal point substantially coincides with the position of the light source, and the major axis is a direction substantially orthogonal to the irradiation direction. At least one elliptical fourth reflecting surface provided above and below one reflecting surface and on the other of the second reflecting surfaces, and having a focal point substantially coincident with the second focal point of the fourth reflecting surface, in the irradiation direction A fifth parabolic reflecting surface for reflecting light, and the second reflecting surface and the fourth reflecting surface. By using a vehicle headlamp provided with a shutter having an opening in the vicinity of the second focal point or a light guide tube surrounded by two or more surfaces, firstly, a request for a vertical width of 50 mm or less is required. Even when there is light, it can be realized without reducing the amount of light, giving the headlamps a degree of design freedom, and improving the overall aesthetics of the vehicle. Secondly, the above-described configuration improves both the light beam capture rate and the light beam utilization rate with respect to the light source, and also has an excellent effect of enabling an extremely bright headlamp with the same power consumption. It is what you play.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a main part of a first embodiment of a vehicle headlamp according to the present invention.
FIG. 2 is a cross-sectional view taken along the line AA in FIG.
FIG. 3 is an explanatory view showing a shutter which is also a main part of the first embodiment.
FIG. 4 is an explanatory view showing a light guide tube that is also a main part of the first embodiment.
FIG. 5 is a cross-sectional view showing the main part of a second embodiment of the vehicle headlamp according to the present invention.
FIG. 6 is an explanatory view showing a third embodiment of a vehicle headlamp according to the present invention.
FIG. 7 is a cross-sectional view showing a conventional example.
FIG. 8 is a cross-sectional view showing another conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1, 10 ... Vehicle headlamp 2, 12 ... Light source 3, 13 ... First reflective surface 4, 14 ... Second reflective surface 41 ... Shutter 42 ... Light guide tube 5, 15 ... First Three reflective surfaces 6, 16 ... Fourth reflective surface 61 ... Shutter 62 ... Light guide tube 7, 17 ... Fifth reflective surface

Claims (4)

A first reflecting surface of a parabolic system that has a focal point that substantially coincides with the position of the light source and that is formed in a narrow area in the vertical direction and is narrow in the vertical direction, and reflects light toward the irradiation direction;
The first focal point substantially coincides with the position of the light source, the major axis is set in a direction substantially perpendicular to the irradiation direction, and the second focal point is provided on either the upper or lower side of the first reflecting surface, and the second focal point is an outer end of the first reflecting surface. A pair of left and right elliptical second reflecting surfaces that reflect light emitted from the light source to either one of the upper and lower sides of the first reflecting surface to the second focal point ; and
A pair is provided outside the first reflecting surface and in the same row as the first reflecting surface, and has a focal point that substantially coincides with the second focal point of the second reflecting surface, and the second reflecting surface is directed toward the irradiation direction. reflects the reflected light, and a third reflecting surface of the parabolic formed narrow in the vertical direction,
The first focal point is substantially coincident with the position of the light source, the major axis is set in a direction substantially perpendicular to the irradiation direction, and the second focal point is provided on the other side of the second reflective surface above and below the first reflective surface . A pair of left and right elliptical fourth reflecting surfaces that are set near the outer end of the three reflecting surfaces and reflect the light emitted from the light source to the other of the second reflecting surfaces to the second reflecting surfaces ;
A narrow width in the vertical direction that is provided outside the third reflecting surface and has a focal point that substantially coincides with the second focal point of the fourth reflecting surface and reflects the light reflected by the fourth reflecting surface toward the irradiation direction. And a fifth reflecting surface formed on
A vehicular headlamp characterized in that a shutter having an opening or a light guide tube surrounded by two or more surfaces is provided in the vicinity of a second focal point between the second reflecting surface and the fourth reflecting surface. The vehicle headlamp according to claim 1, wherein the shutter or the light guide tube is movable, and the light distribution shape is changed by the movement. The vehicle headlamp according to claim 2, wherein the shutter or the light guide tube has two or more places, and the two or more places are configured to be movable by a drive unit. The vehicular headlamp according to any one of claims 1 to 3, wherein an inner surface of the light guide tube is mirror-finished.

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