JPH0220722Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a vehicle headlamp, and in particular to an improved vehicle headlamp that allows a wide range of areas in front of the road to be seen without dazzling oncoming vehicles. It is about lights.

[Background of the idea]

FIG. 7 is an explanatory diagram schematically depicting an example of a conventional vehicle headlamp that can be switched between lighting for normal driving and lighting for passing each other.

A lens 2 is attached to cover the front opening of a reflecting mirror 1 having a paraboloid of revolution shape. Z-Z' is the optical axis, H-
H' is the horizontal axis and V-V is the vertical axis.

For convenience of explanation, regarding the names of left and right, the right side is referred to as right (H) and the left side is referred to as left (H') when viewed in the irradiation direction arrow Z direction.

A main filament 3 of a light source bulb is arranged near the focal point of the paraboloid of revolution reflector 1, and a sub-filament 4 is arranged near the front thereof. Reference numeral 5 denotes a light shielding plate provided below the subfilament 4.

In the above basic structure (Fig. 7), if we consider the state in which the lens 2 is removed, the light flux emitted from the main filament 3 located near the focal point of the paraboloid of revolution reflector 1 is When reflected by the planar reflecting mirror 1, it becomes a horizontal beam of light in the direction of arrow Z.

Since the subfilament 4 is located in front of the focal point, the light beam emitted from the subfilament 4 is not parallel to the optical axis arrow Z. That is, the subfilament light incident on the upper half of the reflecting mirror 1 as shown by the arrow A is reflected as shown by the arrow B, and is projected in a downward direction relative to the arrow Z.

Similarly, the light from the subfilament 4 that entered the right half of the reflector 1 is deflected to the left as shown by arrow D, and the light from the subfilament 4 that entered the left half as shown by arrow E is reflected to the left. It swung to the right and was reflected.

Since the sub-filament 4 is used to form a beam when they pass each other, the light entering the lower half of the reflecting mirror 1 is blocked by the light shielding plate 5, so that no upwardly slanted reflected light is generated. .

The optical path from arrow A to arrow A described above with respect to FIG. As the light passes through the light, the light is adjusted to create the desired light distribution pattern.

The lens 2 of this conventional example is configured for left-hand traffic, and is provided with prism portions A, B, and C.

The prism part A diffuses the light flux pointing to the right, that is, in the direction of illuminating the oncoming traffic lane, to the left and right below the horizontal axis H-H', and forms the light distribution zone shown in FIG.
A′ is formed to avoid dazzling oncoming vehicles.

The prism portion B obliquely cuts the light flux arrow D directed to the left, that is, in the direction of irradiating the driving lane side, to form a light distribution zone B' shown in FIG.

The prism portion C diffuses the downward light beam to the left and right to form a light distribution zone C' shown in FIG.

Regarding the lens 2 schematically shown in FIG. 7, a specific conventional example of prism arrangement is shown in FIG.

The prism portion A shown in FIG. 9 corresponds to the prism portion A described with reference to FIG.

_The prism portions B ₁ and B ₂ shown in FIG. 9 correspond to the prism portion B described in connection with FIG _. This is the part that forms the hot zone.

C ₁ , C ₂ , and C ₃ shown in FIG. 9 correspond to the prism portion C for left and right diffusion explained with reference to FIG.
Specifically, C ₁ is a portion with a small diffusion angle, C ² is a portion with a moderate diffusion angle, and C ₃ is a portion with a large diffusion angle. With this configuration, the illuminance distribution is adjusted within the light distribution zone C' shown in FIG. 8 so that the illuminance near the center is high.

FIG. 10 shows a light distribution pattern of the projected light flux formed by the lens shown in FIG. 9,
A′B′C′ is the light distribution zone A′, B′,
C′ is the integrated light distribution zone.

FIG. 11 shows an example of a state in which a conventional headlamp having the above-mentioned light distribution pattern is used to illuminate the road ahead of the vehicle. This diagram shows a two-lane expressway.
6 is the median distribution zone, and 7 is the left shoulder. At night,
When driving in the left lane, when the front is illuminated with a headlamp having the light distribution pattern shown in FIG. 10, the bright/dark boundary line will be as shown by the solid line 8.

As a result, the area in front of the driver's lane is well illuminated, but since the median strip is not visible, it is difficult to get a sense of the road width, making the driver feel uneasy.

FIG. 12 shows an example of a general road, where 7' is the left shoulder, 9 is the right shoulder, and 10 is the center line. In this case, the bright and dark boundary line will look like 8',
It is difficult to see the shoulder 9 of the oncoming lane, motorcycles near the shoulder, and passersby. In addition, the intersection road 1 shown by the imaginary line
1, it is difficult to see vehicles entering the intersection from the right side.

In order to solve these problems, a vehicle headlamp has been proposed that constitutes a light distribution zone R that illuminates the oncoming lane, as shown in Figure 13 (Jikkosho
59−13685). However, according to this known technology, there are bright zones L and R on both the left and right sides of the front and the front is dark, so the driver's eyes tend to only look at the bright areas on the left and right, which is not favorable for safe driving. .

According to the tests and research conducted by the inventors of the present invention, a bright area clearly protruding above the horizontal line (H-H') on the oncoming lane side (right side), as indicated by the solid line R in Figure 13, appears. It has been confirmed that it is preferable from the viewpoint of driving psychology to configure a pattern in which the upper limit of the bright area gradually increases from the center toward the right side, as shown by the virtual line r, instead of increasing the brightness.

[Purpose of invention]

This idea was created in view of the above circumstances.
It does not adversely affect the original light distribution pattern of a vehicle headlamp, does not cause the risk of dazzling oncoming vehicles, and can be used while driving in the lane on the side away from the median strip (driving lane) on the expressway. The purpose of the present invention is to provide a vehicle headlight that can illuminate a median strip even when driving on a road, and can illuminate the vicinity of the shoulder of an oncoming lane on a general road.

[Summary of the idea]

In order to achieve the above object, the vehicle headlamp of the present invention includes a paraboloid of revolution reflecting mirror, a subfilament for a low beam disposed in front of the focus of the reflecting mirror, and a subfilament for a low beam disposed in front of the focal point of the reflecting mirror. The lens is a prism that directs the light flux of the subfilament reflected by the reflecting mirror to a band extending from side to side below the horizontal line in front of the runway. a prism part that directs the luminous flux to a band including a region above the horizontal line on the driving lane side in front of the driving lane, and a prism part that directs the luminous flux to a band below the horizontal line in front of the driving lane and closer to the oncoming lane side. In addition to the above-mentioned prism parts, an auxiliary prism for directing the luminous flux to a band including above the horizontal line on the oncoming lane side in front of the road. The auxiliary prism part has a plurality of lens steps that are inclined left and right with respect to the vertical direction, and the auxiliary prism part has a plurality of lens steps that are tilted left and right with respect to the vertical direction, and are located below the driving lane in front of the road and above on the opposite lane side. It is characterized by being configured so that the light beam is diffused along an oblique line connecting the two.

[Example of idea]

Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

This embodiment is an example in which the present invention is applied to improve the conventional lens shown in Fig. 9. Fig. 1 in this embodiment is a front view of the lens corresponding to Fig. 9 of the conventional example. be.

Prism portions A, B ₁ , B ₂ , C ₁ , and C ₂ denoted by the same reference numerals as in FIG. 9 are the same components as in the conventional example.

Further, the prism portion C ₃ ″ shown with a dot in the drawing reference number in FIG. 9 is a similar component to that in the conventional example, but it is different from the prism portion C ₃ in the conventional example (FIG. 9). The installation area has been reduced.

An auxiliary prism portion D according to the present invention is provided near the center of the lens where the installation area of the above prism portion C ₃ ″ has been reduced. The system is configured as follows so as to have a function of directing a portion of the reflected light beam to a band including a portion above the horizontal line on the opposite lane side in front of the road.

Parallel diagonal line d ₁ shown in the auxiliary prism part D above
〜d ₄ is the lens step, whose − cross section is the second
As shown in the figure, the concave cylindrical surfaces are arranged in parallel to form a diffusing prism.

A plurality of lens steps constituting the auxiliary lens portion D of the present invention are arranged in the vertical direction V-
The structure is tilted to the left and right compared to V. This embodiment is tilted to the left by an angle θ (corresponding to the right side in the front view of the lens) so that it is suitable as a headlight for left-hand traffic.

With this configuration, the light beam emitted from the subfilament and passing through the auxiliary prism portion D is diffused in a direction inclined by an angle θ with respect to the horizontal line, as shown by the reciprocating arrow 12.

FIG. 3 shows a light projection pattern by the lens of the above-described embodiment (FIG. 1). Light distribution zone A'B'C'' shown by a solid line is a similar light distribution zone corresponding to light distribution zone A'B'C' in the conventional example (Fig. 10).This light distribution zone A'B' An auxiliary light distribution zone D' adjusted by the auxiliary prism portion D is superimposed on C''.

As shown in FIG. 1, the installation area of the auxiliary prism portion D in this embodiment is much smaller than the total area of the lens, so the amount of light passing through this portion is much smaller than the total amount of light; Since this amount of light is diffused to the auxiliary light distribution zone D' in Figure 3, the illuminance of this light distribution zone D' is equal to that of the light distribution zone mentioned above.
It is small compared to the illuminance of A″B′C″. When implementing the present invention, the illuminance of this auxiliary light distribution zone D' is set to be suppressed to the extent that it does not dazzle oncoming vehicles.

In the present invention, the auxiliary prism portion D is provided near the center of the lens. The filament image that emerges from the filament of the headlamp, enters the lens, passes through the lens, and exits forward is a larger image at the center of the lens than at the periphery.

Therefore, this large image is transferred to the aforementioned auxiliary prism D.
Even if the light is diffused by the light, it does not have much effect on the original light distribution pattern of the headlight. Therefore, there is no possibility that the application of the present invention will have an adverse effect on the light distribution pattern.

When the headlights having the light distribution pattern shown in Fig. 3 are used to illuminate the direction of travel on the expressway, the bright/dark boundary line will look like the 8'' mark shown by the chain line in Fig. 11. Delineator 1 provided above
3 can be easily recognized visually, and the driver can easily get a sense of the road width, giving the driver a sense of security.

Further, on general roads, a bright and dark boundary line 8 shown by a chain line in FIG. 12 is obtained, and the road shoulder on the right side (oncoming lane side) can be seen, so it is safe.

In FIG. 12, an area D in which the bright-dark boundary line 8 protrudes toward the oncoming lane compared to the bright-dark boundary line 8' of the conventional example is an auxiliary light distribution pattern D' in the light distribution pattern of this embodiment (FIG. 3). The area is illuminated by a light source, and the illuminance is at a level that does not dazzle oncoming vehicles.

FIG. 4 shows a different embodiment from the above, in which E is an auxiliary prism portion and e ₁ , e ₂ to _{e 7} are lens steps. FIG. 5 shows a - cross section of FIG. 4.

Comparing the lens of this example (Fig. 4) with the previous example (Fig. 1), the auxiliary prism portion E in this example is set to be about twice as wide as the auxiliary prism portion D in the previous example. The lens steps e ₁ to e ₇ are tilted in the front view by an angle θ' in the same direction as in the previous example. Furthermore, as shown in FIG. 5, the lens step is tilted forward by an angle φ relative to the lens surface. This results in
Light incident as shown by arrow A is refracted upward as shown by arrow b. As a result, the auxiliary light distribution zone E′ (Fig. 6) in this example is the same as the auxiliary light distribution zone in the previous example.
It is enlarged upward compared to D' (Fig. 3).

As mentioned above, the auxiliary prism portion E in this example
(Fig. 4) is set larger than the auxiliary prism portion D (Fig. 1) in the previous example, but on the other hand, the auxiliary light distribution zone E' (Fig. 6) in this example is the auxiliary light distribution zone in the previous example. Since zone D' (FIG. 3) is enlarged upward and wider, both auxiliary light distribution zones D' and E' have approximately equal illuminance.

According to the embodiment shown in FIGS. 4 to 6, a bright/dark boundary line 14 shown by a broken line in FIG. 11 and a bright/dark boundary line 14' shown by a broken line in FIG. 12 are formed. The same effects as the embodiment shown in FIG. 3 can be obtained.

[Effect of idea]

As detailed above, the vehicle headlight of the present invention does not cause the risk of dazzling oncoming vehicles, and moreover, when driving on a highway with a median strip, it illuminates the median strip. It can illuminate the area near the right shoulder (oncoming lane) on a general one-lane road, greatly contributing to night traffic safety.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the vehicle headlamp of the present invention, FIG. 1 is a front view of the lens, FIG. 2 is a cross-sectional view of the auxiliary lens portion D in FIG. 1, and FIG. Figure 3 is a chart showing the light distribution pattern. 4 to 6 show embodiments different from the above, FIG. 4 is a front view of the lens, FIG. 5 is a cross-sectional view of FIG. 4, and FIG. 6 is a chart showing a light distribution pattern. . FIG. 7 is a schematic diagram for explaining the configuration of a headlamp, and FIG. 8 is a diagram for explaining the formation of a light distribution pattern in a conventional vehicle headlamp.
FIG. 9 is a front view of a lens in an example of a conventional vehicle headlamp, and FIG. 10 is a chart showing a light distribution pattern in the conventional example. FIGS. 11 and 12 are explanatory diagrams of the illumination state of a driving path, and FIG. 13 is a chart in which the research results of the present inventors are added to the light distribution pattern of a vehicle headlamp according to a known invention. 1...Reflector in the shape of a paraboloid of revolution, 2...Lens,
3... Main filament, 4... Sub filament, 5... Light shielding plate, 6... Median strip, 8,
8', 8'', 8...Bright and dark boundary line, 11...Cross road, 12...Arrow indicating the direction of diffusion, 14, 14'
...Bright and dark boundary line, D, E...Auxiliary prism part,
d ₁ - d ₄ , e ₁ - _{e 7} ... Lens step, D', E' ......
Auxiliary light distribution pattern.

Claims (1)

[Scope of utility model registration request] comprising a paraboloid-shaped reflecting mirror, a subfilament for passing beams arranged in front of the focal point of the reflecting mirror, a light shielding plate covering substantially the lower half of the subfilament, and a lens, and The above lens has a prism part that directs the subfilament light flux reflected by the reflecting mirror into a band that spreads from side to side below the horizontal line in front of the track, and a prism part that directs the light flux to the driving lane side in front of the track above the horizontal line. In a vehicle headlamp, the vehicle headlight includes a prism part that directs the luminous flux to a band including In addition, an auxiliary prism part is provided near the center of the lens for directing the above-mentioned luminous flux to a band including above the horizontal line on the opposite lane side in front of the road. It has a plurality of lens steps that are inclined at an angle, and is configured to diffuse the luminous flux along a diagonal line connecting the lower side of the driving lane in front of the road and the upper side of the oncoming lane. A vehicle headlight characterized by: