JPS636961B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a novel vehicular lamp, and more specifically, in a vehicular lamp having a so-called double filament light source, light from each filament at a different location is used. To provide a vehicular lamp in which all of the light can be controlled to have a predetermined directivity, a suitable light distribution can be obtained, and a lens surface can be illuminated more uniformly. That is.

BACKGROUND TECHNOLOGY AND PROBLEMS It is important to obtain suitable light distribution in lighting equipment for vehicles such as automobiles.Furthermore, when this lighting equipment is a signal lighting equipment such as a rear marker light, it is important that the lens surface is as uniform as possible. It is important to be radiant. This is because these signal lights notify surrounding cars of necessary signals such as braking, directions, starting, etc. by making the lens surface shine.
Also, since it displays the operating status, such as parking, out of order, etc., or the width of the vehicle,
This is because it is necessary to obtain light distribution that can be viewed from a wider range of angles and sufficient and uniform brightness on the lens surface to make the visibility clear. In order to obtain such light distribution performance, in these lamps, the light from the light source is controlled by an appropriate lens element, and generally, the light from the light source is radiated directly toward the lens. Direct light and reflected light that is once reflected by a reflecting mirror are used. In lighting equipment such as the above-mentioned rear marker lights, the direct light is once converted into a parallel beam of light traveling in a direction parallel to the optical axis direction of the lamp body by a prism element such as a refracting prism or a reflecting prism, and is then converted into a parallel beam of light that heads in a direction parallel to the optical axis direction of the lamp body. It is forced to ejaculate.
Regarding the reflected light, by using a parabolic mirror of revolution as the reflecting mirror and arranging the light source at the focal point of the reflecting mirror, the reflected light is made into a parallel light beam and emitted in front of the lamp.

By such control, the parallel light beam is emitted from the lens surface in a substantially uniformly dispersed state, so that the entire surface of the lens surface is illuminated to some extent uniformly. In addition, it is very easy to refract and diffuse the entire parallel light beam in a predetermined direction, and usually one or more outer lenses are provided in front of this lens. The light is diffused while being appropriately given a predetermined directivity by the formed lens element having diffusing properties in the vertical and horizontal directions, thereby making it possible to obtain a desired light distribution.

In this way, in a normal vehicle lamp, the light from the light source is utilized to the maximum, the lens surface is illuminated as uniformly as possible, and the desired light distribution is obtained. In the case where a so-called double filament light source is provided, the above-mentioned extremely disadvantageous problems arise in terms of light distribution performance and brightness performance. This problem will be explained with reference to a conventional vehicle lamp a shown in FIG.

FIG. 1 shows an example of a conventional rear marker light in which a tail lamp and a stop lamp serve as a single lamp body.

In the figure, b indicates a lamp body, a reflective surface c is formed on its inner surface, an inner lens d is attached to its front opening, and an outer lens e is further attached in front of the inner lens d. has been done. The inner lens d has a large number of circular prism elements formed in a concentric pattern on its inner surface. This prism element includes a refractive prism element g,
A refractive prism part h is formed in which a large number of prism elements i, i, ...... are formed in the outer circumferential region thereof, and a total reflection prism part j is formed in which a large number of total reflection prism elements i, i, ...... are formed. There is. Further, on the inner surface of the outer lens e, a large number of fisheye lens elements k, k,
...... is formed. 1 is a bulb, and a filament m for a stop lamp is arranged on the optical axis x-x of the reflecting surface c at a substantially focal point position of the reflecting surface c.
and a tail lamp filament n disposed slightly above the stop lamp filament m and closer to the inner lens d. Each of the prism elements g, g, . . . and i, i, . is formed. That is, each of the refractive prism elements g, g, .
It is cut in such a shape that the direct light incident on it is refracted and emitted in a direction parallel to the optical axis x-x, and each total reflection prism element i, i in the total reflection prism section j , ......, similarly, the direct light emitted from the tail lamp filament n and incident on each prism element i, i, ...... is totally reflected in a direction parallel to the optical axis x-x and exits. It is cut into a shape like this. In this way, each prism element g, g, ... and i,
If i, . . This is particularly noticeable in the prism element located at a short distance from the stop lamp filament m, that is, in the refracting prism section h. That is, the direct light o shown by the solid line in the figure is the direct light from the filament n for the tail lamp, and the direct light p shown by the broken line is the direct light from the filament m for the stop lamp. g, g, ...... After being refracted twice, it is given a predetermined turning angle and is emitted in a direction parallel to the optical axis x-x, but the direct light p is different from the above direct light o. The optical axis x-x cannot be given the same turning angle as
The light is emitted in a direction that is not parallel to the
This results in some serious performance deterioration in the light distribution performance and brightness performance described above. That is, when the Stotsu lamp is turned on, the direct light from the Stotsu lamp filament m is irregularly emitted in a direction that is not parallel to the optical axis x-x when it is emitted from the refracting prism part h, as described above. Therefore, it becomes impossible to perform predetermined light control using the fisheye lens elements k, k, ... of the outer lens e, that is, control to give predetermined directivity in the vertical and horizontal directions and diffuse it to form a predetermined light distribution. Since the light is diffused in different directions, it is impossible to achieve a suitable light distribution. Furthermore, near the boundary between the refraction prism section h and the total reflection prism section j, the light control is transferred from the refraction system to the total reflection system, so it is difficult to control the direct light in this area. Therefore, the efficiency of irradiating light to the outer lens e by each prism element in this boundary part is low, and furthermore, the cut of the prism in this part is not matched to the focal length of the stop lamp filament m. Therefore, the efficiency with which direct light is irradiated onto the lens surface of the outer lens e corresponding to this boundary further decreases, and this
This results in a dark line q as shown in FIG.
Since this dark line q occurs conspicuously when the stop lamp is turned on, even if the stop lamp filament m has a luminous intensity several times that of the tail lamp filament n, this difference in luminous intensity is caused by the dark line q. The light will be canceled out, and the visibility of the light of the stop lamp will be significantly deteriorated.

In addition to the performance deterioration due to the focal length difference between the filament and the filament, this type of vehicle lamp also has the problem that the center part r of the lens shown in Fig. 2 becomes extremely bright, dazzling the following vehicles. It was hot. The reason why the center part r of the lens becomes extremely bright is because the center part r is directly in front of the light source, and is irradiated with direct light from the light source with a luminous flux density several times higher than other parts. In particular, the luminous intensity of the stop light is 55% higher than that of the tail lamp.
Since the luminous intensity is about twice as high as that of the lens, the extreme brightness at the center part r of the lens significantly deteriorates the visibility of the lamp.

Problems to be Solved by the Invention The present invention attempts to solve various problems found in the conventional vehicle lamps having the above-mentioned double filament light source. As a result, it becomes difficult to control the light from the other filament, resulting in poor light distribution performance, uneven brightness on the lens surface, and especially when the other filament is turned on. This is an attempt to solve problems such as the appearance of noticeable dark lines on the lens surface and the fact that the center of the lens surface becomes extremely bright.

Summary of the Invention The present invention provides a vehicular lamp having a double filament light source, in which the light from each of the filaments at different locations can be controlled to have a predetermined directivity. , a suitable light distribution is obtained no matter which filament is turned on, no local dark lines are generated on the lens surface, and the lens surface is illuminated more uniformly, resulting in excellent visibility. The aim is to provide new vehicle lighting equipment.
It includes a lamp body, a lens attached to the front surface of the lamp body, and a light source disposed in a lamp chamber partitioned by the lamp body and the lens, and the light source is arranged in a predetermined position in the lamp chamber. a first filament and a second filament disposed closer to the lens than the first filament, and the first filament is disposed substantially in an area of the lens corresponding to at least the light source in the front-rear direction. The present invention is characterized in that a refractive prism section is formed which includes a long focal length prism element having a focal point at the position and a near focal length prism element having a focal point approximately at the position where the second filament is disposed.

Embodiment FIG. 3 shows an example of an embodiment in which the vehicular lamp of the present invention is applied to a rear marker light for an automobile.

This rear indicator light 1 includes a lamp body 2 having a paraboloid of rotation, an inner lens 3 attached to the front opening of the lamp body 2, and an outer lens 4 attached with a slight distance in front of the inner lens 3. A reflective surface 5 is formed inside the paraboloid of revolution of the lamp body 2, and the lamp chamber defined by the reflective surface 5 and the inner lens 3 has two filaments as a light source. A valve 6 is provided. And as the filament,
A first filament 7 and a second filament 8 located in front of the first filament 7 are arranged one after the other substantially at the focal point of the reflective surface 5 . This first filament 7 is a filament for a stop lamp, and the second filament 8
is a filament for tail lamps. The first filament 7 has a larger coil diameter than the second filament 8,
Further, the first filament 7 and the second filament 8 are arranged substantially in a straight line substantially on the optical axis xx of the lamp body 2.

The inner lens 3 leaves a horizontally long rectangular central region 9 corresponding to the filaments 7, 8 in the front-rear direction on its inner surface, that is, the surface facing the filaments 7, 8, and has a circular outer peripheral region. A strip-shaped total reflection prism element 11 is formed.
These total reflection prism elements 10, 10,...
is the optical axis x of the reflective surface 5 in the inner lens 3
It is formed to draw a concentric pattern approximately centered at the point where -x intersects. Total reflection prism elements 10, 10, . . . in this embodiment
The arrangement position of the second filament 8 is used as a reference for the cut formation of the prism, and the direct light from the second filament 8 is directed to each of the total reflection prism elements 10, 10, . . . It is formed so that it is incident and totally reflected in a direction substantially parallel to the optical axis xx. On the outer surface of the inner lens 3, that is, on the surface facing the outer lens 4, a circular belt-shaped refractive prism element 1 is provided in an area that substantially corresponds to the central area 9 on the inner surface.
A large number of prisms 2, 12, . . . are formed in a concentric pattern to form the refraction prism portion 13. These refractive prism elements 12, 12,
......Also, the total reflection prism elements 10, 1
Similarly to 0, . The refractive prism elements 12, 12, . That is, as shown in FIG. 3C, far focal length prism elements 12A, 12A, . . . and near focal length prism elements 12B, 12B, .
are formed sequentially and alternately. These long focal length prism elements 12A, 12A, ...... are the first filament 7 of the two filaments mentioned above.
It is a refractive prism element whose focal point is approximately at the arrangement position of , and near focal length prism elements 12B, 12
B, . . . are refractive prism elements whose focal point is approximately at the position where the second filament 8 is disposed. and,
Far focal length prism elements 12A, 12A,...
The prism shape is such that the direct light incident from the first filament 7 onto the entrance surface 14 of this prism, that is, the inner surface of the inner lens 3, is emitted from the exit surface 15 of the prism in a direction parallel to the optical axis x-x. The prism shape of the near focal length prism elements 12B, 12B, .
Direct light incident on the inner surface of the prism enters the exit surface 1 of the prism.
6 to a direction parallel to the optical axis x-x. The shape of each prism element is, of course, not limited to the form shown in FIG. Any prism may be used as long as it can provide a turning angle for the injection to be emitted in a certain direction, and the elements of the prism that provide such a turning angle, such as the inclination angle of the exit surface, the curvature of the exit surface, etc. It is formed by setting appropriately. Similarly, the long focal length prism element 12A,
12A, ...... or near focal length prism element 12
B, 12B, ......, the reference focal point position, that is, the focal length with respect to filament 7 or 8, does not change, but the incident angle of the direct light gradually increases from the center to the outer periphery. It is desirable to change the shape of the prism described above in accordance with this change.

A large number of rectangular fisheye lens elements 17, 17, . . . are formed on the inner surface of the outer lens 4.

It is preferable that one of the two filaments disposed within the bulb 6, for example, the first filament 7 for a stop lamp, be disposed at the focal point of the reflecting surface 5. In addition, the total reflection prism section 11
Each total reflection prism element 10, 1 formed in
In this embodiment, the reference for the cut shape is used as the placement position of the second filament 8, but this reference may also be used as the placement position of the first filament 7, as described above. Alternatively, the total reflection prism element 1 may be placed at an intermediate position between the two filaments.
0, 10, ...... are formed in the outer peripheral area of the inner lens, which is quite far from each filament 7 and 8, so even if the filament placement positions differ to some extent, the direct The angle of incidence of light does not change greatly, so even if you try to change the cut shape of the total reflection prism elements 10, 10, etc. in accordance with the slight change in the angle of incidence, generally speaking, it will hardly change. No change occurs in the cut shape.

According to such a rear marker light 1, the direct light irradiated from each filament 7 and 8 to the refraction prism part 13 of the inner lens 3 is on average aligned with the optical axis x- It is refracted in a direction parallel to x. When the second filament 8 is turned on, direct light 18, 18, . . . enters the refraction prism section 13 from the second filament 8.
... are near focal length prism elements 12B, 12B...
..., and is emitted in a direction parallel to the optical axis Light 19, 19,...
... are long focal length prism elements 12A, 12A,
. . . and is also emitted in a direction parallel to the optical axis x-x. Then, each emitted light emitted in a direction parallel to the optical axis x-x is
Fisheye lens elements 17, 17, of the outer lens 4
The light is appropriately refracted up and down and left and right, and diffused up and down and left and right, thereby making it possible to form a predetermined light distribution.

Moreover, the refraction prism section 13 and the total reflection prism section 1
Conventionally, at the boundary with 1, a dark line q
(See Figure 2), but at this boundary,
First and second filaments 7 with different arrangement positions
Since two types of prism elements are formed with focal points at and 8, no matter which filament is lit, on average, the direct light incident on this boundary is directed toward the outer lens 4. Since the light can be irradiated in a direction perpendicular to the outer lens 4, dark lines will no longer occur at this boundary. In particular, when the first and second filaments 7 and 8 are turned on at the same time, that is, when the stop lamp is turned on while the tail lamp is turned on, the direct light that enters this boundary from both filaments 7 and 8 passes through the far focal length prism. Since the element 12A and the near focal length prism element 12B allow the entire outer lens 4 to be irradiated perpendicularly, the occurrence of dark lines can be completely eliminated.

Since each of the refraction prism elements 12, 12, . Direct light with high luminous flux that is concentrated on the center of the lens is emitted in a diffused manner in a direction that does not intersect perpendicularly to the outer lens 4. It is possible to reduce the extremely bright shine. Furthermore, in this embodiment, the tail lamp 8 is disposed in front of the first filament 7, that is, the filament for the stop lamp, and approximately in line with this in the front-rear direction, so that when the stop lamp is turned on, the tail lamp 8 is disposed in front of the filament for the stop lamp. A part of the direct light 20 emitted from the first filament toward the center of the lens is blocked by the second filament 8, which also causes the center of the lens to shine extremely brightly. It is possible to alleviate the
In this case, since the diameter of the coil of the first filament 7 is several times larger than that of the second filament 8, the direct light 20 directed from the first filament 7 toward the center of the inner lens 3 is transmitted to the second filament 7. Even if it is partially blocked by the second filament 8, there is no risk that the shadow of the second filament 8 will appear in the center of the outer lens 4.

Modifications and Application Examples Although the configuration of the vehicle lamp of the present invention is clear from what is shown in the above-described embodiments, the vehicle lamp of the present invention is not limited to the configuration of the above-described embodiments, and can be applied to various modifications or applications. Can provide examples.

That is, the refractive prism section in which the refractive prism elements having two types of focal lengths are formed may be formed on the inner surface of the inner lens, and each refractive prism element having the two types of focal lengths may be formed on the inner surface of the inner lens. , do not necessarily have to be formed sequentially and alternately, but when trying to obtain a certain luminous intensity difference in the lamp, the focal length of one of them should be changed depending on the degree necessary to obtain the luminous intensity difference. A large number of prism elements may be formed, or
Further, in order to control the brightness of the lens surface, the prisms may be partially concentrated to form a prism having one focal length.

Furthermore, as the lens element formed in the outer lens, although a fisheye lens element was used in the above-mentioned embodiment, it is of course not limited to this fisheye lens element, and an appropriate cylindrical lens element or the like may be used to It may be possible to control the diffusion of light.

In addition, in the above-mentioned embodiment, a rear indicator light that serves as both a tail lamp and a stop light was shown as an example, but the present invention can also be freely applied to vehicle lights that serve as various other lights. can.

Effects of the Invention As is clear from the above description, in the vehicle lamp of the present invention, the light source has two filaments, and the arrangement position of the filaments is different in the front and rear. The refractive prism section has two types of focal lengths: a long focal length prism element with one filament as its approximate focal point and a near focal length prism element with the other filament as its approximate focal point. Since it is composed of prism elements, no matter which filament is lit, the direct light from each filament can be emitted as a parallel beam on average, and by doing this, the light can be controlled. This makes it possible to easily distribute light with a predetermined directivity, prevent local dark lines from forming on the lens surface, and prevent the center of the lens from being extremely brightly illuminated. As a result, the lens surface can be made to shine more uniformly over its entire surface.

[Brief explanation of the drawing]

Figure 1 shows an example of a conventional vehicle lamp, where A is a front view with a part of the lens cut away, and B is a front view of A.
FIG. 2 is a front view of the lens showing the brightness of the lens surface caused by the lamp shown in FIG. 1, and FIG. An example is shown in which A is an exploded perspective view, B is a front perspective view of the inner lens, C is an enlarged center vertical side view of the main part of the inner lens, D is a center vertical side view of the lamp shown in Figure A, FIG. 4 is a diagram showing the locus of direct light from the light source of the lamp shown in FIG. 3. Explanation of symbols: 1...vehicle lamp, 2...lamp body, 3...lens, 4...lens, 7...first filament, 8...second filament,
12... Refraction system prism element, 12A... Far focal length prism element, 12B... Near focal length prism element, 13... Refraction prism section.

Claims (1)

[Scope of Claims] 1. The lamp includes a lamp body, a lens attached to the front surface of the lamp body, and a light source disposed in a lamp chamber partitioned by the lamp body and the lens, and the light source is arranged in a predetermined position in the lamp chamber. a first filament disposed at a position nearer to the lens than the first filament, and a second filament disposed at a position closer to the lens than the first filament; A refractive prism section is formed which includes a far focal length prism element having a focal point at the position where the first filament is disposed and a near focal length prism element having a focal point approximately at the position where the second filament is disposed. Lighting equipment for vehicles. 2. The vehicle lamp according to claim 1, wherein the first filament and the second filament are arranged on a line extending in the front-rear direction.