JP6277687B2 - Vehicle headlamp - Google Patents

Description

  The present invention relates to a vehicle headlamp that reflects light from a semiconductor light source as a predetermined light distribution pattern to the front of the vehicle.

A vehicle headlamp that irradiates light from a semiconductor-type light source with a reflector having a plurality of divided reflecting surfaces (hereinafter also referred to as “a plurality of segments”) to form a predetermined light distribution pattern. For example, it is described in Patent Document 1.
The plurality of segments include a cut-off light distribution forming segment that forms a predetermined cut-off light distribution pattern, and a diffuse light distribution that forms a predetermined diffuse light distribution pattern around the predetermined cut-off light distribution pattern. And forming segments.

  The cut-off light distribution pattern has, for example, an oblique cut-off line extending obliquely above the horizontal line from the elbow point near the horizontal line and the vertical line on the screen toward the traveling lane, and the elbow point It is a light distribution pattern that has a lower horizontal cut-off line that overlaps the horizontal line on the opposite lane side or is slightly lower than the horizontal line and substantially parallel to the horizontal line, and is concentrated near the elbow point. Sometimes called a light pattern.

On the other hand, the diffused light distribution pattern has a lower horizontal cut-off line that overlaps the lower horizontal cut-off line of the cut-off light distribution pattern. It is the light distribution pattern provided.
By superimposing these cut-off light distribution patterns (condensed light distribution patterns) and diffused light distribution patterns, a light distribution pattern for low beam (for passing) having an oblique cut-off pattern and a lower horizontal cut-off pattern as a whole. A light distribution pattern) is formed.

  The low beam light distribution pattern is a light distribution pattern having a lower horizontal cut-off line on the oncoming lane side, so that it is possible to prevent glare light from being emitted to the oncoming vehicle side, while an oblique cut-off line is provided on the traveling lane side. Since the light distribution pattern has, it is possible to ensure good forward visibility by illuminating the traveling lane far away.

  From this, it is possible to illuminate the traveling lane side farther by increasing the light intensity near the oblique cut-off line of the cut-off light distribution pattern that ensures good forward visibility, and better forward visibility is obtained. A low beam light distribution pattern can be obtained.

JP 2010-108776 A

Here, in the prior art described in Patent Document 1, the width of the cut-off light distribution forming segment for forming the cut-off light distribution pattern is formed as a segment having a shape with substantially the same width in the vertical direction (vertical direction). .
However, in the cut-off light distribution forming segment as described above, when the size of the reflector in the vertical direction (vertical direction) is limited, the cut-off light distribution pattern extending far away from the vehicle may be insufficiently extended. It was.

  Therefore, the present invention has been made in view of the above problems, and even when the size of the reflector in the vertical direction (up and down direction) is limited, a cut-off light distribution pattern extending away from the vehicle is obtained. An object of the present invention is to provide a vehicle headlamp capable of obtaining good forward visibility.

The present invention has been proposed to achieve the above object, and is grasped by the following configuration.
(1) A vehicle headlamp according to the present invention includes a semiconductor-type light source, a reflector that is disposed below the semiconductor-type light source, and irradiates light from the semiconductor-type light source as a predetermined light distribution pattern in front of the vehicle. The reflector has a cut-off light distribution forming segment that is a reflecting surface that forms a cut-off light distribution pattern at the center of the reflector, and diffused light distribution on both the left and right sides of the cut-off light distribution forming segment It has a diffused light distribution forming segment which is a reflection surface for forming a pattern, and the cut-off light distribution forming segment is formed in a divergent shape whose width is widened from a side closer to the semiconductor-type light source to a side farther from the semiconductor type light source.

(2) In the configuration of (1), the divergent shape has a cut-off distribution when the cut-off light distribution forming segment is viewed as a plane divided into right and left by a reference line along the optical axis of the semiconductor light source. The outer line on the side including the region where the oblique cut-off line of the light pattern is formed is formed so as to spread more outward than the outer line on the opposite side.
(3) In the configuration of (1) or (2), the cut-off light distribution forming segment is formed by being divided into an upper reflective surface and a lower reflective surface, and the upper reflective surface and the lower reflective surface The gaps may be connected gradually and continuously by a connecting surface.
(4) In the configurations of (1) to (3) above, the cut-off light distribution forming segment may be divided into a left reflective surface and a right reflective surface.

  According to the vehicle headlamp of the present invention, even when the vertical size (vertical direction) of the reflector is limited, a cut-off light distribution pattern extending far from the vehicle is obtained, and good forward visibility is obtained. The vehicle headlamp can be provided.

1 is a schematic front view of a vehicle headlamp according to a first embodiment of the present invention. It is the XX sectional view taken on the line of FIG. (A) It is a figure which shows the light distribution pattern on the screen which the reflective surface near the semiconductor type light source of the cut-off light distribution formation segment forms. (B) It is a figure which shows the light distribution pattern on the screen which the reflective surface of the side far from the semiconductor type light source of a cut-off light distribution formation segment forms. (C) It is a figure which shows the whole light distribution pattern (light distribution pattern for low beams). It is a figure explaining the end spread shape of a cut-off light distribution formation segment. It is a schematic front view of the vehicle headlamp which concerns on 2nd Embodiment of this invention. (A) It is a figure explaining the connection shape of the upper side reflective surface and lower side reflective surface of FIG. (B) It is a figure which shows the comparative example of the connection shape with respect to (a). It is a schematic front view of the vehicle headlamp which concerns on 3rd Embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a vehicle headlamp according to the present invention will be described in detail with reference to the drawings. Note that the same reference numerals are given to the same elements throughout the description of the embodiment. In FIG. 3 and FIG. 4, “VU-VD” indicates vertical lines on the upper and lower sides of the screen on which the light distribution pattern is projected. Reference sign “HL-HR” indicates horizontal lines on the left and right of the screen onto which the light distribution pattern is projected. In this specification, front, rear, upper, lower, left, and right are front, rear, upper, lower, left, and right when the vehicle headlamp according to the present invention is mounted on the vehicle. In the description of the embodiments, the same numbers are assigned to the same elements throughout.

(First embodiment)
FIG. 1 is a schematic front view of a vehicular headlamp 1 according to a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line XX of FIG.
The vehicle headlamp 1 according to the first embodiment is, for example, a headlamp that irradiates a light distribution pattern for low beam in front of a vehicle (not shown), and is provided on both the left and right sides of the front portion of the vehicle.
As shown in FIGS. 1 and 2, the vehicle headlamp 1 includes at least a semiconductor-type light source 2 and a reflector 3 that reflects light from the semiconductor-type light source 2 to the front of the vehicle as a predetermined light distribution pattern. Configured.

The semiconductor-type light source 2 is a light source including a self-luminous semiconductor such as an LED or an EL (organic EL), and includes a light emitting unit 20 and a substrate 21. The light emitting unit 20 has a light emitting chip (LED chip) mounted at substantially the center of the lower surface of the substrate 21 and emits light downward.
In addition, the light emission part 20 may consist of a package (LED package) which sealed the light emitting chip (LED chip) with the sealing resin member.

  The light emitting chip of the light emitting unit 20 is rectangular or square, and the light emitting unit 20 is configured by arranging a plurality of, for example, four square light emitting chips. Note that in the light emitting unit 20, one rectangular light emitting chip or one square light emitting chip may be used. Moreover, in the light emission part 20, you may use what arrange | positioned the light emitting chip | tip in 1 row or multiple rows.

The reflector 3 has a shape of a part of the rotating paraboloid, that is, a shape including a lower part, a rear part, and left and right side parts excluding an upper part and a front part of the rotating paraboloid, 300 is provided.
The reflecting surface 300 is a parabolic free-form surface facing the light emitting surface of the light emitting unit 20 facing downward, and has a reference focal point F and a reference optical axis (not shown).
The reference focal point F of the reflecting surface 300 is located at or near the center O of the light emitting surface of the semiconductor light source 2.
The reference optical axis of the reflecting surface 300 passes through the center O of the light emitting surface of the semiconductor light source 2 or the vicinity thereof.

As shown in FIG. 1, the reflecting surface 300 of the reflector 3 is divided into a plurality (11 in this example) of segments 31, 32, and 33 that are juxtaposed in the left-right direction.
In the plurality of segments, the segment at the center of the reflector 3, that is, the segment just below the semiconductor light source 2 is a cutoff light distribution forming segment 31 that forms a cutoff light distribution pattern, and is located on both sides thereof. A plurality of segments are diffusion light distribution forming segments 32 and 33 that form a diffusion light distribution pattern.

More specifically, in the present embodiment, one cut-off light distribution forming segment 31 is provided in the left and right central portion of the reflector 3, and five diffused light distributions are provided on the left and right outer sides (left and right sides). Forming segments 32 and 33 are provided.
The cut-off light distribution pattern formed by the cut-off light distribution forming segment 31 and the diffused light distribution pattern formed by the diffused light distribution forming segments 32 and 33 are overlapped to form a low beam light distribution pattern.

  Here, as described above, in order to illuminate the traveling lane side far and obtain good forward visibility, it is preferable to increase the luminous intensity in the vicinity of the oblique cutoff line of the cutoff light distribution pattern. Hereinafter, the configuration of the cut-off light distribution forming segment 31 for that purpose will be mainly described in detail.

In FIG. 1, the region of the cut-off light distribution forming segment 31 is shown as a region 31U on the side close to the semiconductor light source 2 and a region 31D on the side far from the semiconductor light source 2.
In the cut-off light distribution forming segment 31, the position of the region 31U on the side close to the semiconductor-type light source 2 is close to the light source, so that the light is projected as a large image on the reflecting surface. Is irradiated.

FIG. 3A shows a light distribution pattern P1 on the screen of light irradiated in front of the vehicle in the region 31U on the side close to the semiconductor light source 2.
As shown in FIG. 3A, the reflection surface of the region 31U on the side close to the semiconductor-type light source 2 is obliquely above the horizontal line (HL-HR line) from the elbow point E toward the traveling lane side (left side in the figure). A light distribution pattern P1 having an oblique cut-off line CL1 extending horizontally and a lower horizontal cut-off line CL2 extending horizontally from the elbow point E along the substantially horizontal line (HL-HR line) to the opposite lane side (right side in the figure). For example, it is formed with a free-form surface.

  Note that an upper horizontal cut-off line extending in the horizontal direction in the horizontal direction substantially parallel to the horizontal line may be formed on the outer side (left side in the figure) of the traveling lane side (left side in the figure) on the outer side (left side in the figure). is there.

On the other hand, since the position of the region 31D far from the semiconductor light source 2 is far from the light source, the light is projected onto the reflecting surface as a small image, and the small light image is irradiated forward of the vehicle by the reflecting surface.
The light distribution pattern P2 on the screen of the light irradiated in front of the vehicle in the region 31D far from the semiconductor-type light source 2 is shown by a solid line in FIG.
In FIG. 3B, the light distribution pattern P1 of FIG. 3C, the light distribution pattern shown in FIG. 3B is further overlapped with the diffusion light distribution pattern formed by the diffusion light distribution formation segments 32 and 33, so that the entire light distribution pattern is obtained. The state, that is, the state of the low beam light distribution pattern is shown.

As shown in FIG. 3B, the light emitted toward the front of the vehicle at the position of the region 31D far from the semiconductor-type light source 2 has a smaller reflected light image. The pattern P2 is a light distribution pattern P2 having an oblique cut-off line CL1 and a lower horizontal cut-off line CL2 similar to those shown in FIG. 3A, while the light distribution pattern P1 shown in FIG. The light distribution pattern P2 condensed near the elbow point is formed.
The region 31D far from the semiconductor-type light source 2 is also formed with a free-form surface, for example.

The light distribution patterns P1 and P2 are overlapped to form a cutoff light distribution pattern.
Accordingly, the vicinity of the elbow point is a light distribution pattern formed by overlapping the light distribution pattern P1 and the light distribution pattern P2, so that the luminous intensity is increased.
However, when the size of the reflector 3 in the vertical direction (vertical direction) is limited, a region (in this example, the region 31D) for forming a more condensed light distribution pattern such as the light distribution pattern P2 is sufficiently secured. In this case, the extension of the cut-off light distribution pattern extending far from the vehicle is insufficient.

Therefore, the cut-off light distribution forming segments are not formed with substantially the same width in the vertical direction (vertical direction) as in the prior art, but in the present embodiment, as shown in FIG. By forming the cut-off light distribution forming segment 31 to be wide and diverging, a region 31D on the side far from the semiconductor-type light source 2 where the light image reflected by the reflecting surface is small and a condensed light distribution pattern is easily formed. Try to increase.
As a result, even when the size of the reflector 3 in the vertical direction (up and down direction) is limited, the luminous intensity of the light distribution pattern near the elbow point can be kept high, and a cut-off light distribution pattern extending far from the vehicle is obtained. Good forward visibility can be obtained.
Further, since the outer line of the cut-off light distribution forming segment 31, that is, the outer edge, is formed smoothly without a step, glare generated due to the step or the like is suppressed.

By the way, it is more preferable to increase the luminous intensity in the vicinity of the oblique cut-off line CL1 in order to extend far away on the traveling lane side and irradiate light and obtain good forward visibility.
Therefore, in the present embodiment, the shape of the cut-off light distribution forming segment 31 spreading further is as shown in FIG.
Hereinafter, the divergent shape of the cut-off light distribution forming segment 31 will be described in more detail with reference to FIG.

  4 shows a front view of the reflector 3 viewed from the same direction as FIG. 1, that is, from the side irradiated with light (the vehicle front side), and the cut-off light distribution forming segment 31. Is mainly enlarged, and the light distribution pattern on the screen corresponding to FIG. 3B is shown on the lower side of FIG.

  4 indicates the optical axis of the light emitting section 20 of the semiconductor light source 2, and the region 31D on the far side from the semiconductor light source 2 of the cut-off light distribution forming segment 31 previously shown. Further, the outer region extending to the right end of the optical axis and extending outward is 31R, and the outer region on the left side of the optical axis is 31L.

  The region 31R and the region 31L have a light distribution state in the vicinity of the oblique cutoff line CL1, as indicated by an arrow with respect to the light distribution pattern P2 on the screen shown in the lower side of FIG. This portion is formed so as to spread outward so as to be wider than the region 31L on the opposite side.

  In other words, the cut-off light distribution forming segment 31 includes a region 31R that forms an oblique cut-off line CL1 when viewed as a plane that is divided into right and left by a reference line along the optical axis of the light emitting unit 20 of the semiconductor light source 2. The outer side line of the cut-off light distribution forming segment 31 on the other side is formed so as to be broader outward than the outer line of the cut-off light distribution forming segment 31 on the side including the region 31L on the opposite side.

For this reason, since the vicinity of the oblique cutoff line CL1 of the light distribution pattern P2 is formed using light from a wider range of reflecting surfaces, the luminous intensity in the vicinity of the oblique cutoff line CL1 can be increased. .
As a result, it is possible to extend far away on the traveling lane side and irradiate the light, so that better forward visibility can be obtained.

In the example shown in FIG. 4, the outer line of the cut-off light distribution forming segment 31 on the region 31L side is also formed so as to gradually spread outward, but this region 31L has a lower horizontal cut-off line CL2. It is a region that bears the vicinity, and it is not necessary to irradiate as far as the vicinity of the above-described oblique cutoff line CL1, and therefore, it is not necessarily formed so as to spread outward.
Further, in this embodiment, the outer line of the cut-off light distribution forming segment is configured to gradually widen away from the semiconductor-type light source 2 so as to be gently curved. It may be.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS.
In the first embodiment, the cut-off light distribution forming segment 31 is configured as one surface that is smoothly curved without being divided.
On the other hand, in the second embodiment, as shown in FIG. 5, the cut-off light distribution forming segment 31 of the reflector 3 </ b> B is divided into a region 31 </ b> U close to the semiconductor light source 2 and a region 31 </ b> D far from the semiconductor light source 2. Forming.
That is, it is divided into an upper reflection surface close to the semiconductor-type light source 2 and a lower reflection surface far from the semiconductor-type light source 2.

When forming the cut-off light distribution forming segment, if there is not much change in curvature in the vertical and horizontal directions and it is formed as one surface, the light distribution pattern P1, which is a slightly wide range of light distribution constituting the cut-off light distribution pattern, is given priority. In other words, if priority is given to the shape of the free curved surface of the region 31U close to the semiconductor light source 2, the curvature state of the region 31D far from the semiconductor light source 2 is also affected by this, so the light distribution of the light distribution pattern P2 that is desired to increase the light concentration is high. It may not be increased.
Similarly, if priority is given to the light distribution pattern P2 having a high degree of light condensing constituting the cutoff light distribution pattern, the light distribution pattern P1 may not be widened.

  On the other hand, in the cut-off light distribution forming segment 31, the light distribution pattern P2 is designed so that a desired light distribution state can be obtained with the region 31U close to the semiconductor light source 2 for obtaining the light distribution pattern P1 as an upper reflective surface. If the region 31D far from the semiconductor-type light source 2 is used as a lower reflective surface, the light distribution pattern P1 and the light distribution pattern P2 each have a more optimal light distribution state. Therefore, the cut-off light distribution pattern obtained by superimposing these can be easily made into a more desirable light distribution state.

However, in this case, a connecting surface 31T for connecting the upper reflecting surface and the lower reflecting surface having different curvatures is provided (see FIG. 5).
FIG. 6 shows a cross-sectional view of the cut-off light distribution forming segment 31 of the reflector 3B shown in FIG. 5, and FIG. 6 (a) shows the state of the connecting surface 31T of this embodiment, as a comparative example. FIG. 6B shows a connecting surface 41T.

When the connecting surface 41T has a large step as in the reflector 4 shown in FIG. 6B, when the undercoat is formed on the reflecting surface of the reflector 3B, the undercoat material is formed on the stepped portion. Since the reflective coating deposited and deposited thereon is deposited according to the shape of the pool, the portion where the undercoat material is pooled becomes a distorted reflective portion.
In this case, it is not desirable because light may be scattered at that portion or glare light may be generated.

Therefore, as shown in FIG. 6A, if the connecting surface 31T is formed so as to be continuously connected as gently as possible, it is possible to suppress the undercoat material from accumulating on the connecting surface 31T. It is possible to suppress the light scattering and the generation of glare light as described above.
Accordingly, the cut-off light distribution forming segment 31 is divided into the upper reflective surface and the lower reflective surface, and the connecting surface 31T between the upper reflective surface and the lower reflective surface is formed by the upper reflective surface and the lower reflective surface. By connecting the reflecting surface gently and continuously, it is possible to form a more suitable cut-off light distribution pattern while suppressing the occurrence of light scattering and glare light.

(Third embodiment)
A third embodiment of the present invention will be described with reference to FIG.
In the third embodiment, the reflector 3B of the second embodiment is further divided into left and right surfaces as shown in FIG.

More specifically, in FIG. 4, the cut-off light distribution forming segment 31 of the reflector 3C is divided into left and right reflecting surfaces along a line along the optical axis of the light emitting unit 20 of the semiconductor light source 2 indicated by one-point diagonal lines. Yes.
Therefore, the upper reflective surface that is the region 31U close to the semiconductor-type light source 2 is divided into the left-side upper reflective surface 31UL and the right-side upper reflective surface 31UR, and the lower reflective surface that is the region 31D far from the semiconductor-type light source 2 Is also divided into a left lower reflecting surface 31DL and a right lower reflecting surface 31DR.

  As described so far, the upper reflective surface, which is the region 31U close to the semiconductor light source 2, is a portion that forms a light distribution pattern on the screen as shown in FIG. When divided into left and right, the light distribution pattern formed by the left upper reflection surface 31UL and the light distribution pattern formed by the right upper reflection surface 31UR form a light distribution pattern corresponding to the light distribution pattern P1, respectively. It becomes possible.

  Here, the light distribution pattern corresponding to the light distribution pattern P1 formed by the left upper reflection surface 31UL is referred to as a UL light distribution pattern P1, and similarly, the light distribution pattern P1 formed by the right upper reflection surface 31UR is the UR distribution. When referred to as the light pattern P1, the UL light distribution pattern P1 and the UR light distribution pattern P1 overlap each other, and finally, a light distribution pattern P1 as shown in FIG. 3A is formed.

  Therefore, in the present embodiment, the UL light distribution pattern P1 and the UR light distribution pattern P1 can be finely adjusted so that the most dominant light distribution pattern P1 is in a more optimal light distribution state. Thus, a more suitable light distribution pattern P1 can be formed.

  The same applies to the lower reflective surface, and the left lower reflective surface 31DL and the right lower reflective surface 31DR are finely adjusted, and light distribution patterns formed by the reflective surfaces (31DL, 31DR) are adjusted. Since it is possible to obtain the most preferential light distribution pattern P2 by combining them, a more suitable light distribution pattern P2 can be formed.

  Since the more optimized light distribution pattern P1 and light distribution pattern P2 overlap each other to form a cut-off light distribution pattern, the configuration of the third embodiment further provides a suitable cut-off. A light distribution pattern can be formed.

The preferred embodiment of the present invention has been described in detail above. However, the present invention is not limited to the above-described embodiment. For example, both the left and right sides of the cut-off light distribution forming segment 31 as the diffused light distribution forming segments 32 and 33. 5 shows a case where five segments are formed, but the number of the segments may be less than or greater than five.
As described above, various modifications and changes can be made within the scope of the present invention described in the claims.

DESCRIPTION OF SYMBOLS 1 Vehicle headlamp 2 Semiconductor type light source 3, 3B, 3C Reflector 20 Light emission part 21 Board | substrate 31 Cut-off light distribution formation segment 31U Area | region near the semiconductor type light source 31D Area | region far from a semiconductor type light source 32, 33 Diffusion Light distribution forming segment 300 Reflecting surface CL1 Oblique cut-off line CL2 Horizontal cut-off line E Elbow point

Claims (3)

A vehicle headlamp, a semiconductor light source,
A reflector disposed on the lower side of the semiconductor-type light source, and irradiating the front of the vehicle with light from the semiconductor-type light source as a predetermined light distribution pattern;
The reflector has a cut-off light distribution forming segment that is a reflecting surface that forms a cut-off light distribution pattern at the center of the reflector, and forms a diffuse light distribution pattern on both the left and right sides of the cut-off light distribution forming segment. Having a diffused light distribution forming segment that is a reflective surface,
The cut-off light distribution forming segment is formed in a divergent shape in which the width widens from the side closer to the semiconductor-type light source toward the far side ,
The divergent shape makes the cut-off light distribution forming segment an optical axis of the semiconductor light source
When the cut-off light distribution pattern is oblique,
The outer line on the side that includes the area that forms the cut-off line is on the opposite side of the outer line.
A vehicular headlamp characterized in that it is formed so as to spread more outward than in . The cut-off light distribution forming segment is formed by dividing into an upper reflective surface and a lower reflective surface,
The vehicular headlamp according to claim 1, wherein the upper reflective surface and the lower reflective surface are gently and continuously connected by a connecting surface. The vehicular headlamp according to claim 1 or 2 , wherein the cut-off light distribution forming segment is divided into a left reflecting surface and a right reflecting surface.