This application is a U.S. National Stage Application under 35 U.S.C § 371 of International Patent Application No. PCT/JP2019/019271 filed May 15, 2019, which claims the benefit of priority to Japanese Patent Application No. 2018-118349 filed Jun. 21, 2018, the disclosures of all of which are hereby incorporated by reference in their entireties.
The present invention relates to a vehicle lighting fixture, and in particular, to a vehicle lighting fixture capable of preventing the luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of a low-beam light distribution pattern from becoming relatively high, and also capable of forming a low-beam light distribution pattern with a uniform vertical thickness in a horizontal direction.
Conventionally, there has been proposed a vehicle lighting fixture including a projection lens constituted by a first lens and a second lens, a light guide lens disposed behind the projection lens, and a low-beam light source that is disposed behind the light guide lens and emits light for forming a low-beam light distribution pattern by being irradiated forward through the light guide lens and the projection lens in this order (e.g., see Patent Literature 1 (
Patent Document 1: Japanese Patent Application Laid-Open No. 2015-79660
However, the present inventors have studied the foregoing vehicle lighting fixture made in accordance with the conventional art described above, and found that although the vehicle lighting fixture satisfies the legal requirements for the low-beam light distribution pattern, the luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of the low-beam light distribution pattern becomes relatively high to cause luminous intensity unevenness (luminance unevenness), and the thickness of the central portion of the low-beam light distribution pattern becomes smaller than those at both left and right ends, and as a result, the light distribution feeling is reduced.
The present invention has been made in view of the foregoing circumstances, and an object thereof is to provide a vehicle lighting fixture capable of suppressing the luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of the low-beam light distribution pattern from becoming relatively high, and also capable of forming a low-beam light distribution pattern with a uniform vertical thickness with respect to the horizontal direction (i.e., it is possible to suppress the light distribution feeling from being reduced).
To achieve the foregoing object, an aspect of the present invention is a vehicle lighting fixture including a projection lens, a separator disposed behind the projection lens, and a low-beam light source that is disposed behind the separator and emits light for forming a low-beam light distribution pattern by being irradiated forward through the separator and the projection lens in this order. This vehicle lighting fixture is characterized in that: the separator includes an upper separator body that includes a front surface and a rear surface on the opposite side thereof, and a first light guide portion that extends from a lower portion of the upper separator body toward the low-beam light source and has a first light incident surface located at a tip end thereof and faces the low-beam light source; that the projection lens has a front surface and a rear surface on the opposite side thereof, and the rear surface of the projection lens has an upper light incident surface facing the front surface of the upper separate body; that the low-beam light source, the first light guide portion, the upper separator body, and the upper light incident surface are each disposed above a reference axis passing through the focal point of the projection lens and extending in a vehicle longitudinal direction; that the lower portion of the front surface of the upper separator body is in surface contact with the lower portion of the upper light incident surface of the rear surface of the projection lens; that a space is formed between a portion above the lower portion of the front surface of the upper separator body and a portion above the lower portion of the upper light incident surface of the rear surface of the projection lens; and that the light emitted from the low-beam light source enters the first light guide portion through the first light incident portion, and a part of the light is directly outputted from the front surface of the upper separator body, and another part of the light is guided within the upper separator body while being repeatedly totally reflected between the front surface and the rear surface of the upper separator body and then outputted through the front surface of the upper separator body and further enters the projection lens through the upper light incident surface of the projection lens to be projected by the projection lens, so that the light is used for forming the low-beam light distribution pattern.
In the above-described invention, a preferable mode is characterized in that a distance between the front surface of the upper separator body and the upper light incident surface of the rear surface of the projection lens becomes wider upward.
In the above-described invention, a preferable mode is characterized in that the surface shape of the upper light incident surface of the rear surface of the projection lens is adjusted in such a manner that the luminous intensity distribution of the low-beam light distribution pattern satisfies the legal requirements and the thickness of the low-beam light distribution pattern in the vertical direction is uniform with respect to the horizontal direction.
Further, in the above-described invention, a preferable mode is characterized by further including an ADB light source that emits light that is irradiated forward while passing the separator and the projection lens in this order to form an ADB light distribution pattern, and in that the separator includes a lower separator body that includes a front surface and a rear surface on the opposite side thereof, and a second light guide portion that extends from an upper portion of the lower separator body toward the ADB light source and has a second light incident surface located at a tip end thereof and facing the ABD light source; that the rear surface of the projection lens further has a lower light incident surface facing the front surface of the lower separator body; that the ADB light source, the second light guide portion, the lower separator body, and the lower light incident surface are each disposed below the reference axis; and that the front surface of the lower separator body is in surface contact with the lower light incident surface of the rear surface of the projection lens.
Hereinafter, a vehicle lighting fixture 10, which is an embodiment of the present invention, will be described with reference to the accompanying drawings. Corresponding components in the respective drawings are denoted by the same reference numerals, and a repetitive description thereof will be omitted.
The vehicle lighting fixture 10 shown in
As shown in
As shown in
The front surface 22a includes a light source module mounting surface 22a1 and a peripheral surface 22a2 surrounding the light source module mounting surface 22a1.
The light source module mounting surface 22a1 and the peripheral surface 22a2 are each, for example, a plane parallel to a plane including the Y-axis and the Z-axis.
Screw holes 22a5 are provided in the light source module mounting surface 22a1 (in
The peripheral surface 22a2 includes a holder abutment surface 22a3 against which the holder 40 abuts, and a retainer abutment surface 22a4 against which the retainer 70 abuts.
The retainer abutment surface 22a4 is provided on each of the left and right sides of the peripheral surface 22a2.
The thickness between the retainer abutment surface 22a4 and the rear surface 22b (thickness in the X-axis direction) is thicker than the thickness between the holder abutment surface 22a3 and the rear surface 22b (thickness in the X-axis direction), so as to constitute a step portion.
Screw holes 22c, into which screw N1 is inserted, are provided in the base 22 (in
First extension portions 24 are provided to the left and right sides of the base 22 to extend from the left and right sides of the base 22 rearward (X-axis direction). At the tip end portion of the first extension portion 24, a second extension portion 26 extending sideward (Y-axis direction) is provided.
Heat dissipation fins 28 are provided to the rear surface 22b of the base 22.
The light source module 30 includes a plurality of low-beam light sources 32a and a plurality of ADB light sources 32b, and a substrate 34 on which the plurality of low-beam light sources 32a, the plurality of ADB light sources 32b, and connectors 34c are mounted.
As shown in
Each of the light sources 32a, 32b is, for example, a semiconductor light emitting element such as an LED or LD with a light emitting surface of a rectangular (e.g., 1 mm square), and is mounted on the substrate 34 in a state in which the respective light emitting surface is directed forward (front). A plurality of rectangles in
In the substrate 34, there are provided through holes 34a into which positioning pins 22a6 of the heat sink 20 are inserted (in
A light source module 30 with the above-described configuration is fixed to the heat sink 20 by screwing the screws N2 inserted into the notches S1 to the screw holes 22a5 of the heat sink 20 (the light source module mounting surface 22a1), while the positioning pins 22a6 of the heat sink 20 are inserted into the through holes 34a of the substrate 34.
As shown in
The holder body 42 has a front surface 42a that is configured as a surface with the following shape (or a concave spherical surface to the rear). The front surface 42a is formed by inverting the rear surface of the separator 50 so that the rear surface of the separator 50 (rear surface 52b of the upper separator body 52 and the rear surface 53b of the lower separator body 53) is in surface contact with the front surface 42a.
In the holder body 42, a through hole 42c in which the first light guide portion 52d and the second light guide portion 53d of the separator 50 are inserted is provided.
To the holder body 42, a cylindrical portion 44 extending toward the rear (X-axis direction) from the outer peripheral portion of the holder body 42 is provided. Then, at the tip end portion of the cylindrical portion 44, a flange portion 46 to abut against the holder abutment surface 22a3 of the heat sink 20 is provided.
In the holder main body 42 (and the cylindrical portion 44), a notch S4 is provided.
On the front side open end surface 40a of the holder 40, projected portions 48 and projected portions 49 are provided.
As shown in
As shown in
The upper separator body 52 has a front surface 52a that is configured as a surface with a shape (concave spherical surface to the rear) that is formed by inverting the upper half of the rear surface 60b of the primary lens 60 so that the upper half, above the reference axis AX, of the rear surface 60b of the primary lens 60 (convex spherical surface to the rear) is in surface contact with the front surface 52a.
The upper separator body 52 has a rear surface 52b (see
As shown in
The stepped edge portion 52a1 includes a side e1 corresponding to the left horizontal cut-off line CL1, a side e2 corresponding to the right horizontal cut-off line CL2, and a side e3 corresponding to the oblique cut-off line CL3 connecting the left horizontal cut-off line CL1 and the right horizontal cut-off line CL2.
The extended edge portion 52a2 is disposed at the same position as the side e1 with respect to the Z-axis direction. The extended edge portion 52a3 is disposed at the same position as the side e2 with respect to the Z-axis direction.
The upper separator body 52 has a lower end surface 52c (see
As shown in
A first light incident surface 52e is provided at the tip end portion of the first light guide portion 52d. The first light incident surface 52e is, for example, a plane parallel to a plane including the Y-axis and the Z-axis.
The first light incident surface 52e is disposed at a position where it faces the light source module 30 (the light emitting surfaces of the plurality of low-beam light sources 32a) (see
As shown in
The lower separator body 53 has a front surface 53a that is configured as a surface with a shape (concave spherical surface to the rear) that is formed by inverting the lower half of the rear surface 60b of the primary lens 60 so that the lower half, below the reference axis AX, of the rear surface 60b of the primary lens 60 (convex spherical surface to the rear) is in surface contact with the front surface 53a.
The lower separator body 53 has a rear surface 53b (see
As shown in
The extended edge portion 53a2 is disposed at the same position as the side e1′ with respect to the Z-axis direction. The extended edge portion 53a3 is disposed at the same position as the side e2′ with respect to the Z-axis direction.
The lower separator body 53 has an upper end surface 53c (see
As shown in
A second light incident surface 53e is provided at the tip end portion of the second light guide portion 53d. The second light incident surface 53e is a surface adjusted such that a plurality of regions constituting the ADB light distribution pattern (e.g., a plurality of regions A1 to A4 which are individually turned on and off) are prevented from becoming circular and overlapping with each other as shown in
The second light incident surface 53e is disposed at a position where it faces the light source module 30 (the light emitting surfaces of the plurality of ADB light sources 32b) (see
As shown in
It should be noted that the lower separator body 53 has a notch S5 so that the connectors 34c of the light source module 30 do not abut against (interfere with) the lower separator body 53.
As shown in
The separator 50 with the above-described configuration is disposed in such a manner that the first light guide portion 52d of the upper separator body 52 and the second light guide portion 53d of the upper separator body 52 are inserted into the through holes 42c of the holder 40 (e.g., press-fit or fit), that the first light incident surface 52e of the upper separator body 52 (the first light guide portion 52d) and the light source module 30 (the light emitting surfaces of the plurality of low-beam light sources 32a) face each other and the second light incident surface 53e of the lower separator body 53 (the second light guide portion 53d) and the light source module 30 (the light emitting surfaces of the plurality of ADB light sources 32b) face each other (see
At that time, the projected portions 48 of the holder 40 are inserted into the through hole 52f1 of the upper separator body 52 and the through holes 53f1 of the lower separator body 53 (see
As shown in
As shown in
As shown in
The lens body 82 includes a front surface 82a and a rear surface 82b on the opposite side thereto (see
To the outer peripheral portion of the lens body 82, a cylindrical portion 84 extending from the outer peripheral portion of the lens body 82 toward the rear (X-axis direction) is provided.
The primary lens 60 and the secondary lens 80 constitute a projection lens with a focal point F (see
As the primary lens 60 and the secondary lens 80 constituting the projection lens, for example, a spherical lens and a plano-convex lens described in Japanese Patent Application Laid-Open No. 2015-79660 may be used.
The secondary lens 80 with the above-described configuration has the lens body 82 disposed in front of the primary lens 60, and a pressing and screw receiving portion 86 disposed in contact with the flange portion 76 of the retainer 70 (see
In the vehicle lighting fixture 10 with the above-described configuration, when the plurality of low-beam light sources 32a are turned on, light from the plurality of low-beam light sources 32a is incident on the first light incident surface 52e of the first light guide portion 52d of the upper separator body 52, is guided within the first light guide portion 52d and is outputted from the front surface 52a of the upper separator body 52. As a result, the luminous intensity distribution corresponding to the low-beam light distribution pattern is formed on the front surface 52a of the upper separator body 52. The luminous intensity distribution includes the sides e1 to e3 (see
When the plurality of ADB light sources 32b are turned on, light from the plurality of ADB light sources 32b is incident on the second light incident surface 53e of the second light guide portion 53d of the lower separator body 53, is guided within the second light guide portion 53d, and is outputted from the front surface 53a of the lower separator body 53. As a result, the luminous intensity distribution corresponding to the ADB light distribution pattern is formed on the front surface 53a of the lower separator body 53. The luminous intensity distribution includes the sides e1′ to e3′ (see
When the plurality of low-beam light sources 32a and the plurality of ADB light sources 32b are turned on, the composite light distribution pattern including the low-beam light distribution pattern PLo and the ADB light distribution pattern PADB is formed as shown in
The present inventors have studied and found that the conventional vehicle lighting fixture with the above-described conventional art configuration, although satisfying the legal requirements for the low-beam light distribution pattern, forms the low-beam light distribution pattern with a portion (e.g., a portion around 4 degrees below the horizontal line) whose luminous intensity becomes relatively high, and, for example, causes luminous intensity unevenness (luminance unevenness), resulting in reducing the light distribution feeling.
The reason why the luminous intensity at a portion of the low-beam light distribution pattern (e.g., a portion around 4 degrees below the horizontal line) becomes high is that, of the light from the low-beam light source 32a, light whose luminous intensity is relatively strong (e.g., light in a narrow angle direction with respect to an optical axis AX32a of the low-beam light source 32a (see
As shown in
Although the detailed reason why the thickness TC of the central portion of the low-beam light distribution pattern PLo becomes thin as compared with the thicknesses TL and TR of both the left and right sides thereof is unknown, it can be considered as follows.
That is, it is considered to be due to that, first, the thickness of the upper separator body 52 along the reference axis AX with respect to the horizontal direction become thicker as it moves away from the reference axis AX (see thicknesses T1 and T2 in
For example, of the upper separator body 52, a portion farther from the reference axis AX (e.g., the portion with the thickness T2 in
Further, the present inventors have studied this matter and found that: when the low-beam light distribution pattern is required to have a long length in the vertical direction, a lower density (narrow bright range), and a low maximum luminous intensity as compared with the ADB light distribution pattern, as shown in
Next, as a second embodiment, a vehicle lighting fixture 10A capable of preventing the luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of the low-beam light distribution pattern from becoming relatively high, and also capable of forming a low-beam light distribution pattern with a uniform vertical thickness with respect to the horizontal direction (i.e., it is possible to suppress the light distribution feeling from being reduced) will be described. Note that “uniform” used in this specification is not limited to the meaning of the term uniform in a strict sense. That is, it is considered as being “uniform” as long as it can be visually evaluated as being uniform or substantially uniform.
The vehicle lighting fixture 10A of the present embodiment is different from the vehicle lighting fixture 10 of the above-described first embodiment in that a separator 50A is used instead of the separator 50, and a primary lens 60A is used instead of the primary lens 60. Except for this, the configuration thereof is the same as that of the above-described first embodiment. Hereinafter, differences from the above-described first embodiment will be mainly described, and the same components are denoted by the same reference numerals, and descriptions thereof will be omitted as appropriate.
As shown in
As in the first embodiment, the low-beam light sources 32a, the ADB light sources 32b, the separator 50A, the primary lens 60A, and the secondary lens 80 are held by the heat sink 20, the holder 40, the retainer 70 and the like to maintain the positional relationship shown in
The secondary lens 80 (the front surface 82a and the rear surface 82b) and the primary lens 60A (the front surface 60a) constitute a projection lens 90. Specifically, the projection lens 90 is constituted by, out of one or a plurality of lenses (in this embodiment, the primary lens 60A and the secondary lens 80), the optical surface(s) (in this embodiment, the front surface 60a of the primary lens 60A and the front surface 82a and rear surface 82b of the secondary lens 80) other than the rear surface of the rearmost lens (in this embodiment, the rear surface 60Ab of the primary lens 60A). The focal plane FP of the projection lens 90 is, for example, a spherical surface with a constant curvature (see
As shown in
The separator 50A is made of a silicon resin, and is a cup-shaped member in which a front side is opened and a rear side is closed, as shown in
As shown in
The upper separator body 52A is disposed above the reference axis AX, and the lower separator body 53 is disposed below the reference axis AX.
The upper separator body 52A is a thin plate-shaped light guide portion including a front surface 52Aa and a rear surface 52Ab on the opposite side thereof. Specifically, the upper separator body 52A is a thin plate-shaped light guide portion, in a horizontal cross-section, curved along the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A (see
As shown in
The lower portion of the front surface 52Aa of the upper separator body 52A is in surface contact with the lower portion of the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A. Further, a space S is formed between a portion above the lower portion of the front surface 52Aa of the upper separator body 52A and a portion above the lower portion of the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A.
The distance (space S) between the front surface 52Aa of the upper separator body 52A and the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A increases upward. A relationship between the front surface 52Aa of the upper separator body 52A and the rear focal plane FP of the projection lens 90 (curvature of field. see
Incidentally, since the light from the low-beam light sources 32a outputted from the first light guide portion 52d of the upper separator body 52A (the front surface 52Aa) becomes diffused light, the light reaching the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A weakens as the distance (space S) between the front surface 52Aa of the upper separator body 52A and the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A becomes wider (i.e., upward from the reference axis AX). As a result, the low-beam light distribution pattern becomes an ideal luminous intensity distribution that decreases in a gradation manner from the upper edge downward.
The vertical length H1 (see
The front surface 52Aa of the upper separator body 52A is configured to be, for example, a slightly convex curved surface to the front such that the light from the low-beam light sources 32a to be guided through the upper separator body 52A while being repeatedly totally reflected between the front surface 52Aa and the rear surface 52Ab of the upper separator body 52A is outputted from the front surface 52Aa of the upper separator body 52A (see
The thickness T of the upper separator body 52A (see
As shown in
The first extension portion 54 and the second extension portion 55 are so-called bridging portions for which no optical function is intended. The first extension portion 54 extends from the upper end portion of the upper separator body 52A toward the front. The second extension portion 55 extends from the front end portion of the first extension portion 54 along the rear surface 60Ab of the primary lens 60A.
The lower separator body 53 is a thin plate-shaped light guide portion including a front surface 53a and a rear surface 53b on the opposite side thereof. The upper edge of the front surface 53a of the lower separator body 53 includes a stepped edge portion 53a1 of the shape obtained by inverting the stepped edge portion 52a1, similarly to the above-described first embodiment (not shown in
The second light guide portion 53d extends from the upper portion of the lower separator body 53 (rear surface 53b) toward the ADB light sources 32b and has a second light incident surface 53e provided at the tip end thereof and facing the ADB light sources 32b. The second light incident surface 53e is a surface through which the light from the ADB light sources 32b enters the separator 50A (the second light guide portion 53d) and is, for example, a plane parallel to a plane including the Y-axis and Z-axis.
As shown in
The primary lens 60A is made of a transparent resin such as an acrylic resin or a polycarbonate resin, and is a spherical lens including a front surface 60a and a rear surface 60Ab on the opposite side thereof as shown in
The rear surface 60Ab of the primary lens 60A includes an upper light incident surface 60Ab1 disposed above the reference axis AX and a lower light incident surface 60Ab2 disposed below the reference axis AX.
The upper light incident surface 60Ab1 is a surface through which light from the low-beam light sources 32a outputted from the front surface 52Aa of the upper separator body 52A enters the primary lens 60A. The upper light incident surface 60Ab1 is provided in a region of the rear surface 60Ab of the primary lens 60A to which the front surface 52Aa of the upper separator body 52A faces.
The lower portion of the upper light incident surface 60Ab1 coincides with the rear focal plane FP of the projection lens 90. On the other hand, the portion above the lower portion of the upper light incident surface 60Ab1 does not coincide with the rear focal plane FP of the projection lens 90, but is inclined forward with respect to the rear focal plane FP.
The surface shape of the upper light incident surface 60Ab1 is adjusted in such a manner that it satisfies the legal requirements required for the low-beam light distribution pattern, luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of the low-beam light distribution pattern can be suppressed from becoming relatively high, and the thickness of the pattern in the vertical direction becomes uniform with respect to the horizontal direction (i.e., it is possible to suppress the light distribution feeling from being reduced). For example, the surface shape of the upper light incident surface 60Ab1 is adjusted in such a manner that the luminous intensity distribution of the low-beam light distribution pattern decreases in a gradation manner from the upper edge of the low-beam light distribution pattern downward. It should be noted that in some cases, the surface shape of the front surface 52Aa of the upper separator body 52A may be adjusted in the same manner.
Since the surface shape of the thus adjusted upper light incident surface 60Ab1 becomes a complex free curved surface, it is difficult to represent the surface shape of the upper light incident surface 60Ab1 by specific numerical values and the like.
However, it is possible to find the surface shape of the upper light incident surface 60Ab1 that forms the low-beam light distribution pattern—that satisfies the legal requirements required for the low-beam light distribution pattern, is capable of suppressing luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of the low-beam light distribution pattern from becoming relatively high, and uniforms the thickness of the pattern in the vertical direction with respect to the horizontal direction, (i.e., it is possible to suppress the light distribution feeling from being reduced)—by, for example, using a predetermined simulation software to adjust the surface shape of the upper light incident surface 60Ab1, and by, each time it is adjusted, confirming the low-beam light distribution pattern (luminous intensity distribution, etc.).
The lower light incident surface 60Ab2 is a surface through which light from the ADB light sources 32b outputted from the front surface 53a of the lower separator body 53 enters the primary lens 60A. The lower light incident surface 60Ab2 is provided in a region of the rear surface 60Ab of the primary lens 60A to which the front surface 53a of the lower separator body 53 faces. The lower light incident surface 60Ab2 coincides with the rear focal plane FP of the projection lens 90.
As shown in
As shown in
The distance between the second region B2 and the focal plane FP of the projection lens 90 becomes wider upward from the reference axis AX. On the other hand, the distance between the third region B3 and the focal plane FP of the projection lens 90 becomes wider downward from the reference axis AX.
It should be noted that the adjustment of the first region B1 can adjust the vertical length of the relatively high luminous intensity band with a relative high luminous intensity near the cut-off line of the low-beam light distribution pattern and the vertical length of the relatively high luminous intensity band with a relative high luminous intensity near the lower edge of the ADB light distribution pattern. Further, the adjustment of the second region B2 can adjust the vertical length of the low-beam light distribution pattern. In addition, the adjustment of the third region B3 can adjust the vertical length of the ADB light distribution pattern.
The secondary lens 80 is made of a transparent resin such as an acrylic resin or a polycarbonate resin, and is a plano-convex lens including a front surface 82a and a rear surface 82b on the opposite side thereof. The front surface 82a is a plane parallel to the plane including the Y-axis and Z-axis, and the rear surface 82b is a convex spherical surface to the rear.
In the vehicle lighting fixture 10A with the above-described configuration, when the low-beam light sources 32a are turned on, light from the low-beam light sources 32a enters the separator 50A (the first light guide portion 52d) through the first light incident surface 52e.
As shown in
Further, of the light from the low-beam light source 32a that has entered the separator 50A (the first light guide portion 52d), another part of light, for example, light Ray2 with a relatively weak luminous intensity (e.g., light in the wide angle direction with respect to the optical axis AX32a of the low-beam light sources 32a) is guided within the upper separator body 52A while being repeatedly totally reflected between the front surface 52Aa and the rear surface 52Ab of the upper separator body 52A to be outputted through the front surface 52Aa of the upper separator body 52A, further enters the primary lens 60A through the upper light incident surface 60Ab1 of the primary lens 60A, and is projected by the projection lens 90 constituted by the primary lens 60A and the secondary lens 80, to be used for forming the low-beam light distribution pattern.
The present inventors have confirmed that the low-beam light distribution pattern formed as described above satisfies the legal requirements for the low-beam light distribution pattern, as shown in
Although the detailed reason why the luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of the low-beam light distribution pattern is not high is unknown, it can be considered as follows.
That is, since the space S is formed between the front surface 52Aa of the upper separator body 52A and the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A, the light Ray1 with the relatively strong luminous intensity out of the light from the low-beam light sources 32a that has entered the separator 50A (the first light guide portion 52d) is refracted (diffused), and further, Fresnel reflected each time when it is outputted through the front surface 52Aa of the upper separator body 52A and when the light enters the primary lens 60A through the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A. As a result, it is considered that light travelling toward the portion (e.g., a portion around 4 degrees below the horizontal line) of the low-beam light distribution pattern is reduced.
The detailed reason why the vertical thickness is uniformly formed with respect to the horizontal direction is unknown, but the following can be considered.
Specifically, it is considered that, since the space S is formed between the front surface 52Aa of the upper separator body 52A and the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A, the light Ray1 with the relatively strong luminous intensity out of the light from the low-beam light sources 32a that has entered the separator 50A (the first light guide portion 52d) is refracted (diffused) when entering the primary lens 60A through the rear surface 60Ab (the upper light incident surface 60Ab1) of the primary lens 60A, and a part of the light is projected to a portion (mainly, the lower region of the central portion) with a relatively low luminous intensity in the low-beam light distribution pattern by the projection lens 90 constituted by the primary lens 60A and the secondary lens 80.
Further, it is considered to be because the light from the low-beam light sources 32a guided within the upper separator body 52A while being repeatedly totally reflected between the front surface 52Aa and the rear surface 52Ab of the upper separator body 52A and outputted from the front surface 52Aa of the upper separator body 52A is projected to a portion (mainly, the lower region of the central portion) with a relatively low luminous intensity in the low-beam light distribution pattern by the projection lens 90 constituted by the primary lens 60A and the secondary lens 80.
In addition, the present inventors have confirmed that the low-beam light distribution pattern formed as described above has a longer vertical length (T3<T4 in
The reason why the low-beam light distribution pattern becomes long in the vertical direction as compared with the ADB light distribution pattern is considered that the second region B2 is arranged forward with respect to the focal plane FP of the projection lens 90 (or rearward), and thus the light from the low-beam light sources 32a that has outputted from the front surface 52Aa of the upper separator body 52A and entered the primary lens 60A through the upper light incident surface 60Ab1 of the primary lens 60A is projected in a blurred state by the projection lens 90 constituted by the primary lens 60A and the secondary lens 80.
Further, the reason why the low-beam light distribution pattern has a lower density (narrower bright range) and lower maximum luminous intensity, as compared with the ADB light distribution pattern, is the same reason as the reason why the luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of the above-described low-beam light distribution pattern is not high.
It should be noted that the reason why the width W2 of the low-beam light distribution pattern PLo is wider than the width W1 of the ADB light distribution pattern PADB in
It should be noted that, when the ADB light sources 32b are turned on, the ADB light distribution pattern PADB is formed, and when the low-beam light sources 32a and the ADB light sources 32b are turned on, the composite light distribution pattern including the low-beam light distribution pattern PLo and the ADB light distribution pattern PADB is formed. This point of issue is the same as that of the first embodiment, and therefore the description thereof is omitted here.
In addition, the present inventors have confirmed that the contour of the ADB light distribution pattern formed as described above is formed in an appropriately blurred state.
The reason why the contour of the ADB light distribution pattern is formed in an appropriately blurred state is considered that, since the third region B3 is disposed rearward with respect to the focal plane FP of the projection lens 90 (or frontward), the light from the ADB light source 32b outputted from the front surface 53a of the lower separator body 53 and further and entering the primary lens 60A from the lower light incident surface 60Ab2 of the primary lens 60A is projected in a blurred state by the projection lens 90 constituted by the primary lens 60A and the secondary lens 80.
As described above, according to the present embodiment, there can be provided the vehicle lighting fixture 10A capable of suppressing the luminous intensity at a portion (e.g., a portion around 4 degrees below the horizontal line) of the low-beam light distribution pattern from becoming relatively high, and capable of forming the low-beam light distribution pattern with a uniform thickness in the vertical direction with respect to the horizontal direction (i.e., capable of suppressing the light distribution feeling from being reduced).
Further, according to the present embodiment, there can be provided the vehicle lighting fixture 10A capable of forming the low low-beam light distribution pattern with a longer length in the vertical direction, a lower density (narrow bright range), and a low maximum luminous intensity, as compared with the ADB light distribution pattern, and the ADB light distribution pattern whose contour is appropriately blurred.
The present inventors have studied and found that, in the conventional vehicle lighting fixture with the above-described conventional art configuration, a gap S13 is generated in some cases between the front surface 52Aa of the upper separator body 52A, through which the light from the low-beam light sources 32a is outputted, and the front surface 53a of the lower separator body 53, through which the light from the ADB light sources 32b is outputted, as shown in
Next, as a third embodiment, a description regarding a vehicle lighting fixture 10B will be described, which is capable of smoothening the luminous intensity change between the low-beam light distribution pattern PLo and the ADB light distribution pattern PADB and suppressing the light distribution feeling from being reduced, even when a gap S13 is generated between the front surface 52Aa of the upper separator body 52A, through which the light from the low-beam light sources 32a is outputted, and the front surface 53a of the lower separator body 53, through which the light from the ADB light sources 32b is outputted.
The vehicle lighting fixture 10B of the present embodiment is different from the vehicle lighting fixture 10A of the above-described second embodiment in that a separator 50B is used instead of the separator 50A. Except for this, the configuration is the same as that of the above-described second embodiment. Hereinafter, differences from the above-described second embodiment will be mainly described, and similar components are denoted by the same reference numerals, and descriptions thereof will be omitted as appropriate.
The separator 50B shown in
The separator 50B is different from the separator 50A of the above-described second embodiment in that, as shown in
As shown in
The thickness T3 of the overlap portion 57 is, for example, 0.2 mm. It should be noted that, in order to suppress the transmittance of light from the low-beam light sources 32a outputted through the front surface 52Aa of the upper separator body 52B from being reduced, it is desirable that the thickness T3 of the overlap portion 57 be as thin as possible.
The overlap portion 57 is disposed with the gap S15 formed between the rear surface 57b of the overlap portion 57 and the front surface 52Aa of the upper separator body 52B so that the light Ray3 from the ADB light sources 32b guided within the overlap portion 57 while being repeatedly totally reflected between the front surface 57a and the rear surface 57b of the overlap portion 57 is outputted through the front surface 57a of the overlap portion 57. The gap S15 is, for example, 0.02 mm.
In the vehicle lighting fixture 10B with the above-described configuration, when the low-beam light sources 32a and the ADB light sources 32b are simultaneously turned on, light from the low-beam light sources 32a enters the separator 50B (the first light guide portion 52d) through the first light incident surface 52e.
Of the light from the low-beam light sources 32a that has entered the separator 50B (the first light guide portion 52d), a part of light, for example, light Ray1 with a relatively strong luminous intensity (e.g., see
Further, of the light from the low-beam light sources 32a which has entered the separator 50B (the first light guide portion 52d), another part of light, for example, light Ray2 with a relatively weak luminous intensity (e.g., see
On the other hand, the light from the ADB light sources 32b enters the separator 50B (the second light guide portion 53d) through the second light incident surface 53e.
Of the light from the ADB light sources 32b that has entered the separator 50B (the second light guide portion 53d), a part thereof is directly outputted from the upper portion of the front surface 53a of the lower separator body 53B, further enters the primary lens 60A through the lower light incident surface 60Ab2 of the primary lens 60A, and is projected by the projection lens 90 constituted by the primary lens 60A and the secondary lens 80, to be used for forming the ADB light distribution pattern.
As shown in
The present inventors have confirmed that the composite light distribution pattern including the low-beam light distribution pattern and the ADB light distribution pattern formed as described above is configured such that the luminous intensity change between the low-beam light distribution pattern PLo and the ADB light distribution pattern PADB becomes smooth, as shown in
As described above, according to the present embodiment, there can be provided a vehicle lighting fixture 10B capable of smoothening the luminous intensity change between the low-beam light distribution pattern PLo and the ADB light distribution pattern PADB and suppressing the light distribution feeling from being reduced even when the gap S13 is generated between the front surface 52Aa of the upper separator body 52B, through which the light from the low-beam light sources 32a is outputted, and the front surface 53a of the lower separator body 53B, through which the light from the ADB light sources 32b is outputted.
Next, a modified example will be described.
In the third embodiment described above, an example has been described in which the overlap portion 57 in which the upper portion of the front end portion of the lower separator body 53B extends upward is used as the overlap portion, but the present invention is not limited thereto. For example, as shown in
The overlap portion 58 is a thin-film light guide portion including a front surface 58a facing the lower light incident surface 60Ab2 (not shown in
The thickness T4 of the overlap portion 58 is, for example, 0.2 mm. It should be noted that, in order to suppress the transmittance of light from the ADB light sources 32b outputted through the front surface 53a of the lower separator body 53B from being reduced, it is desirable that the thickness T4 of the overlap portion 58 be as thin as possible.
The overlap portion 58 is disposed with the gap S16 formed between the rear surface 58b of the overlap portion 58 and the front surface 53a of the lower separator body 53B so that the light from the low-beam light sources 32a guided within the overlap portion 58 while being repeatedly totally reflected between the front surface 58a and the rear surface 58b of the overlap portion 58 is outputted through the front surface 58a of the overlap portion 58. The gap S16 is, for example, 0.02 mm.
In this modified example, when the low-beam light sources 32a and the ADB light sources 32b are simultaneously turned on, light from the low-beam light sources 32a enters the separator 50B (the first light guide portion 52d) through the first light incident surface 52e.
Of the light from the low-beam light sources 32a that has entered the separator 50B (the first light guide portion 52d), light Ray1 with a relatively strong luminous intensity (e.g., see
Further, of the light from the low-beam light sources 32a which has entered the separator 50B (the first light guide portion 52d), light Ray2 with a relatively weak luminous intensity (e.g., see
Furthermore, of the light from the low-beam light sources 32b that has entered the separator 50B (the first light guide portion 52d), another part thereof (refer to a light beam indicated by reference numeral Ray4 in
On the other hand, the light from the ADB light sources 32b enters the separator 50B (the second light guide portion 53d) through the second light incident surface 53e.
Of the light from the ADB light sources 32b that has entered the separator 50B (the second light guide portion 53d), a part thereof is directly outputted from the upper portion of the front surface 53a of the lower separator body 53B, further enters the primary lens 60A through the lower light incident surface 60Ab2 of the primary lens 60A, and is projected by the projection lens 90 constituted by the primary lens 60A and the secondary lens 80, to be used for forming the ADB light distribution pattern.
The present inventors have confirmed that the composite light distribution pattern including the low-beam light distribution pattern and the ADB light distribution pattern formed as described above is configured such that the luminous intensity change between the low-beam light distribution pattern PLo and the ADB light distribution pattern PADB becomes smooth, as shown in
In the above-described third embodiment, an example in which the overlap portion 57 is applied to the separator 50A of the vehicle lighting fixture 10A of the second embodiment has been described, but the present invention is not limited thereto. For example, the overlap portion 57 may be applied to the separator 50 of the vehicle lighting fixture 10A of the first embodiment and the other separators. The same applies to the overlap portion 58.
In the above-described embodiment, an example has been described in which the projection lens 90 constituted by two lenses, i.e., the primary lens 60A and the secondary lens 80, is used as the projection lens, but the present invention is not limited thereto. For example, although not shown, a projection lens constituted by a single lens or a projection lens constituted by three or more lenses may be used as the projection lens.
In the above-described embodiment, an example in which the separator 50A including the upper separator body 52A, the first light guide portion 52d, the lower separator body 53, and the second light guide portion 53d is used as the separator has been described, but the present invention is not limited thereto. For example, similarly to the above-described conventional art, a separator including the upper separator body 52A and the first light guide portion 52d and not including the lower separator body 53 and the second light guide portion 53d may be used as the separator. That is, the lower separator body 53 and the second light guide portion 53d may be omitted.
In the above-described embodiment, an example in which a spherical surface that has a constant curvature (see
All of the numerical values shown in the above-described respective embodiments are illustrative, and it is needless to say that appropriate numerical values different from those may be used.
The above-described embodiments are merely illustrative in all respects. The present invention is not to be construed as being limited by the description of the above-described respective embodiments. The invention may be embodied in various other modes without departing from the spirit or principal characteristics thereof.
10 . . . Vehicle lighting fixture, 20 . . . Heat sink, 22 . . . Base, 22a . . . Front surface, 22a1 . . . Light source module mounting surface, 22a2 . . . Peripheral surface, 22a3 . . . Holder abutment surface, 22a4 . . . Retainer abutment surface, 22a5 . . . Screw hole, 22a6 . . . Positioning pin, 22b . . . Rear surface, 22c . . . Screw hole, 24 . . . first extension portion, 26 . . . second extension portion, 28 . . . Heat dissipation fin, 30 . . . Light source module, 32a . . . Low-beam light source, 32b . . . ADB light source, 34 . . . Substrate, 34a . . . Through hole, 34c . . . Connector, 40 . . . Holder, 40a . . . Front side open end surface, 42 . . . Holder body, 42a . . . Front surface, 42c . . . Through hole, 44 . . . Cylindrical portion, 46 . . . Flange portion, 48 . . . Projected portion, 49 . . . Projected portion, 50, 50A . . . Separator, 52, 52A . . . Upper separator portion, 52a, 52Aa . . . Front surface, 52a1 . . . Stepped edge portion, 52a2 . . . Extended edge portion, 52a3 . . . Extended edge portion, 52b, 52Ab . . . Rear surface, 52c . . . Lower end surface, 52d . . . First light guide portion, 52e . . . First light incident surface, 52f . . . Flange portion, 52f1 . . . Through hole, 52f2 . . . Through hole, 52g . . . Light guide portion, 52h . . . Light incident surface, 53 . . . Lower separator body, 53a . . . Front surface, 53a1 . . . Stepped edge portion, 53a2 . . . Extended edge portion, 53a3 . . . Extended edge portion, 53b . . . Rear surface, 53c . . . Upper end surface, 53d . . . Second light guide portion, 53e . . . Second light incident surface, 53f . . . Flange portion, 53f1 . . . Through hole, 53g . . . Light guide portion, 53h . . . Light incident surface, 60, 60A . . . Primary lens, 60a . . . Front surface, 60b, 60Ab . . . Rear surface, 60Ab1 . . . Upper light incident surface, 60Ab2 . . . Lower light incident surface, 62 . . . Flange portion, 70 . . . Retainer, 72 . . . Retainer body, 76 . . . Flange portion, 80 . . . Secondary lens, 82 . . . Lens body, 82a . . . Front surface, 82b . . . Rear surface, 84 . . . Cylindrical portion, 86 . . . Pressing and screw receiving portion, 88 . . . Positioning pin, AX . . . Reference axis, CL . . . Cut-off line, CL1 . . . Left horizontal cut-off line, CL2 . . . Right horizontal cut-off line, CL3 . . . Cut-off line, CLADB . . . Cut-off line, CLLo, . . . Cut-off line, F . . . Focus, N1, N2 . . . Screw, PADB . . . ADB light distribution pattern, PLo, . . . Low-beam pattern.
Number | Date | Country | Kind |
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JP2018-118349 | Jun 2018 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2019/019271 | 5/15/2019 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2019/244519 | 12/26/2019 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
20190162385 | Paradis | May 2019 | A1 |
Number | Date | Country |
---|---|---|
2015-79660 | Apr 2015 | JP |
2018-83533 | May 2018 | JP |
2018117230 | Jun 2018 | WO |
2018123850 | Jul 2018 | WO |
2019244519 | Dec 2019 | WO |
Entry |
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International Search Report and Written Opinion of the International Search Report for PCT/JP2019/019271 dated Aug. 6, 2019. |
Number | Date | Country | |
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20210270440 A1 | Sep 2021 | US |