JPH0241124B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a parabolic reflector for a headlamp used by being attached to a vehicle such as an automobile, and particularly relates to a composite reflector having a plurality of reflecting surfaces. .

[Conventional technology]

Generally speaking, this type of composite reflector is
The structure disclosed in Japanese Patent No. -145002 is known. The main parts of this known reflecting mirror are shown in FIGS. 14 and 15. In these figures, 10 is a composite reflector, 11 is a front lens, and the composite reflector 10
has parabolic cylindrical surfaces 10a and 10b which are vertically divided into a plurality of reflecting surfaces. FIG. 16 shows a light distribution pattern of passing beams obtained by this known reflecting mirror. In this figure, A shows a light distribution pattern reflected by the parabolic cylinder surface 10a, and B shows a light distribution pattern reflected by the parabolic cylinder surface 10b.

[Problem that the invention seeks to solve]

In the conventional composite reflector, each of the reflector reflection surfaces for traveling or passing each other is formed of a collection of parabolic cylindrical surfaces, and each of these parabolic cylindrical surfaces has a function of reflecting parallel light rays. In particular, the light distribution pattern of the reflected light at the portion 10b that reflects the light 15° above the passing beam is rectangular as substantially parallel reflected light at the 15° angle, as is clear from Fig. 16. It forms an elongated light distribution pattern, and the horizontal line H formed by the other parabolic cylinder surface 10a
There is a problem that a valley C is formed between the light distribution pattern A and the light distribution pattern A that is reflected under the light, and the reflected light does not reach the valley C, and the valley portion becomes a dark area.

In addition, in forming the parabolic cylindrical surface 10b, it is clearly separated from the parabolic cylindrical surface 10a,
In particular, since the upper boundary part of the parabolic cylinder surface 10b is clearly divided, even in the light distribution pattern 15 degrees upward of the passing beam, it becomes a rectangular shape divided as described above, and the upper boundary part is clearly defined. There is also the problem that glare light is generated at the boundary between the two.

[Means for Solving the Problems] As a specific means for solving the above-mentioned problems, the present invention provides a composite reflecting mirror formed of a large number of parabolic cylindrical surfaces. Provided is a composite reflector for a headlamp, characterized in that a conical surface is formed on a portion thereof,
By forming a group of conical surfaces, not only is there no step difference and no glare light is generated, but there is also no cut in the 15° upward portion of the passing beam.

〔Example〕

Next, the present invention will be explained in more detail based on several illustrated embodiments. First, in the first embodiment shown in FIGS. It is formed by arranging columnar surfaces 2 adjacent to each other. A light source mounting portion 3 is provided approximately at the center of this composite reflecting mirror, and when viewed from the front, the reflecting surface can be distinguished from top to bottom and left and right by a vertical line V passing through the center and a horizontal line H.

In such a composite reflecting mirror 1, a conical surface 4 is formed below the horizontal line and in a part of the reflecting mirror. As shown in Fig. 2, this conical surface 4 has X, Y, and Z coordinates with the center of the reflecting mirror as O, and the intersection line l between the parabolic cylinder surface 2 and the XZ plane is the Z axis. A conical surface 4 is formed by rotating it around the center in the direction indicated by arrow a. When this conical surface is stopped at an appropriate position, a step is created between it and the lower parabolic cylinder surface, and this becomes the lower end line l' of the conical surface 4. Therefore, the intersection line 1 can be said to be substantially the upper end line of the conical surface 4 on the parabolic cylinder surface.

The optical image of the filament on the conical surface 4 thus formed, that is, the state of reflection will be explained with reference to FIGS. 3 and 4. The light source used is an example of a C-8/C-8H bulb such as an _H4 bulb. First, in FIG. 3, 5 is a running filament, 6 is a passing filament, and the running filament 5 is the general focus f of each parabolic cylinder group.
When the traveling filament 5 is placed above or slightly backward, a filament image 5a is obtained on the end line l of the parabolic cylinder surface 2, and a filament pattern 5b obtained by reflection on the front surface of the reflecting mirror is formed on the horizontal line H. becomes almost parallel. Since the conical surface 4 is formed by rotating around the Z-axis from the upper end line l of the parabolic cylinder surface, the filament pattern 5b rotates from the lower end line l to the parabolic cylinder surface. As it moves toward line l', it sequentially rotates from horizontal line H along arrow a'.

Moreover, as shown in FIG. 4, when the passing filament 6 is placed in front of the general focus f of the parabolic cylinder group, a filament image 6a is obtained on the end line of the parabolic cylinder, and this is reflected. The filament pattern 6b obtained on the front surface of the reflecting mirror is approximately parallel to the horizontal line H. Since the conical surface 4 is formed by rotating around the Z-axis from the upper end line l of the parabolic cylinder surface, the filament pattern 6b also rotates from the lower end line l in accordance with the rotation. As it goes to line l', it sequentially rotates from the horizontal line H along the arrow a''.

A conical surface 4 having such characteristics is used as a reflective area A.
When the area above the horizontal line H is the reflective area B and the area below the horizontal line H is the reflective area C, the light distribution pattern when the traveling filament 5 is turned on is as shown in FIG. In other words, since an _H4 bulb (halogen bulb) is used as a light source, when the light source is on the focal point or behind it, the left and right sides are reversed with respect to the vertical line V, and the conical surface 4 is formed. Reflective area A is patterned on the left side.
A′ is projected, and other areas B, C pattern B′,
C′ are located at the top and bottom, respectively, resulting in a light distribution pattern that spreads in the lateral direction as a whole.

When the passing filament 6 is turned on, the passing filament 6 is inverted vertically with respect to the horizontal line H because it is located in front of the focal point position. Therefore, as shown in FIG. 6, the reflection at the reflection area A of the conical surface 4 forms a pattern A' with an upward slope of approximately 15 degrees above the horizontal line H, and the reflection area B forms a pattern A' above the horizontal line H. Pattern B' is formed below. In the reflection area C, there is no reflected light because there is a hood under the passing filament and light to this area is blocked.

No matter which filament is lit, the reflection at the reflective area A of the conical surface 4 becomes radiant light, so the overall pattern is fan-shaped, and the light is delivered with appropriate brightness to the areas that require the amount of light. It reflects it. The conical surface 4 is formed so that the boundary with the upper parabolic cylinder surface 2, that is, the upper end line l of the parabolic cylinder surface is substantially level-free, and no glare light is generated in the passing beams. It is.

In the second embodiment shown in FIGS. 7 to 10,
The conical surface 4 is provided symmetrically with respect to the vertical line V, so that it can be immediately adapted to both left-hand traffic and right-hand traffic.
The means for forming the parabolic cylinder surface 2 and the conical surface 4 are substantially the same as those in the first embodiment. In the conical surfaces 4 provided on the left and right sides, when the right conical surface is the reflective area A ₁ and the left conical surface is the reflective area A ₂ , when the traveling filament is turned on,
The patterns A ₁ ′, A ₂ ′, B ′, and C ′ in each area are aggregated to form the light distribution pattern shown in Fig. 8, and when the passing filament is turned on, the light distribution pattern shown in Fig. 9 or Fig. 10 is obtained. becomes the light distribution pattern. The light distribution pattern shown in Fig. 9 is for right-hand traffic, and only patterns A _{1 ′} and B′ of reflection areas A ₁ and B occur, and reflection areas A ₂ and C are provided at the bottom of the filament for passing each other. The hood blocks light and prevents reflected light from occurring. Conversely, Fig. 10 shows a light distribution pattern for left-hand traffic, with reflective areas A ₂ and B
Patterns A ₂ ' and B' are generated, and patterns due to reflection in other areas are not generated.

In this case, prepare a composite reflector in advance,
Depending on the mounting angle of the hood attached to the passing filament, driving on the right or left can be arbitrarily selected. Even if the conical surfaces are in symmetrical positions, there is no problem in turning on the traveling beam.

Furthermore, a third embodiment shown in FIGS. 11 to 13 will be described. In this embodiment, a conical surface is used to concentrate the strong light of the traveling beam at the center. In other words, the conical surface 4 may be made wider below the horizontal line H, which is not used as the reflective area of the passing filament. The conical surface 4 is formed by the first
As described in the embodiment, since it is formed by rotating around the Z axis, the light reflected from that surface will be concentrated at the center.

Therefore, in FIG. 11, most of both sides below the horizontal line H are formed as a conical surface 4, leaving a parabolic cylinder surface 2' near the middle. and,
The reflective area on the conical surface 4 is divided into A ₁ , A ₂ , and A ₃ , and the reflective area above the horizontal line H is divided into B
When looking at the light distribution pattern with the lower part as the reflective area C, when the traveling filament is turned on, the light distribution pattern becomes as shown in FIG. 12, and the reflective area A ₁ ,
Patterns A _{1 ′} and A ₂ ′ of A 2 condense light in the center, and the condensed portion partially overlaps the horizontal line H, forming a region with high illuminance in the center.

In addition, when the filament for passing each other is turned on, as shown in FIG.
A pattern A 1 ′ in which most of A ₂ is shielded, and a part of the reflection area A ₁ on the right side and the reflection area A ₃ are diagonally 15 _degrees ,
By forming A ₃ ', an ideal light distribution pattern for the passing beam can be obtained.

In any of the examples, the conical surface is formed by rotating the parabolic cylinder surface around the Z axis in the XZ plane, so it is formed continuously with the parabolic cylinder surface with almost no difference in level. When the filaments for passing each other are lit, no glare light is generated due to the difference in level.

〔Effect of the invention〕

As explained above, the composite reflector for a headlamp according to the present invention has a conical surface formed on a part of the reflective surface formed by a large number of parabolic cylinder surfaces, so that the reflection reflected from the reflective area of the conical surface is reduced. The light becomes synchrotron radiation, which can be effectively used as a 15° fan-shaped light distribution pattern in the passing beam.Moreover, the end line at the top of the conical surface is formed in a series with almost no boundary between it and the parabolic cylinder surface. Since there are no steps, not only can a seamless light distribution pattern be obtained with other reflective areas, but also there is no generation of glare light, which provides various excellent effects.

Also, by providing the conical surfaces symmetrically,
It has the excellent effect of being able to be used for both left-hand traffic and right-hand traffic.

Furthermore, by forming conical surfaces in most of the positions where the light of the passing filament is not reflected,
When the traveling filament is turned on, the light is focused in the center, and it has the excellent effect of being visible from a distance when the illuminance is high.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a composite reflecting mirror according to a first embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining the means for forming a conical surface in the same embodiment, and FIG. FIG. 4 is an explanatory diagram for explaining the reflection state of the running filament on the conical surface, FIG. 4 is an explanatory diagram for explaining the reflection state of the passing filament on the conical surface in the same embodiment, and FIG.
The figure is a light distribution pattern diagram of a traveling beam of the same embodiment, FIG. 6 is a diagram of a light distribution pattern of a passing beam of the same embodiment, and FIG. 7 is a front view showing a composite reflector of a second embodiment according to the present invention. , FIG. 8 is a diagram of the light distribution pattern of the driving beam of the same embodiment, FIG. 9 is a diagram of the light distribution pattern of the passing beam in the case of right-hand traffic of the same embodiment, and FIG.
Figure 0 is a light distribution pattern of a passing beam for left-hand traffic, Figure 11 is a front view showing a composite reflector according to a third embodiment of the present invention, and Figure 12 is a light distribution pattern of a driving beam of the same embodiment. Fig. 13 is a light distribution pattern diagram of the passing beam of the same embodiment, Fig. 14 is a front view of a conventional compound reflector, and Fig. 15 is a diagram of the case where a lens is attached to the same reflector. FIG. 16, a sectional view taken along the line -, is a light distribution pattern diagram of a passing beam according to the conventional example. 1... Composite reflecting mirror, 2, 2'... Parabolic cylindrical surface, 3
...Light source mounting position, 4...Conical surface, 5...Filament for running, 6...Filament for passing each other, H...Horizontal line, V...Vertical line.

Claims (1)

[Scope of Claims] 1. A composite reflection mirror for a headlamp, characterized in that a conical surface is formed in a part of the composite reflection mirror below the horizontal line passing through the center in the composite reflection mirror formed by a large number of parabolic cylindrical surfaces. mirror. 2. The composite reflector for a headlamp according to item 1 above, wherein the conical surface is symmetrically provided with respect to a vertical line. 3. The composite reflector for a headlamp according to item 1 above, wherein conical surfaces are formed in most of the positions where the light of the passing filament is not reflected.