Lighting fixtures and vehicle headlights

Abstract

A vehicular headlamp (1) serving as a lamp fitting comprises a board (40) on which a first light source (41) and a second light source (42) serving as light sources are mounted, a heat sink (20) on which the board (40) is disposed, and a reflector unit (50) which presses the board (40) against the heat sink (20) and which reflects a portion of light emitted from the first light source (41) and the second light source (42), wherein: the board (40) has recessed portions (45) that are recessed from each of mutually opposing side surfaces (40sf); the first light source (41) and the second light source (42) are positioned inward of bottom portions (45B) of each of the recessed portions (45); and the reflector unit (50) presses parts of the board (40) outward of the bottom portions (45B) of each of the recessed portion (45).

Description

Technical Field

[0001] The present invention relates to a lighting fixture and a vehicle headlamp.

Background Art

[0002] A lighting fixture provided with a reflector unit for forming a predetermined light distribution pattern is known, and such a lighting fixture is disclosed in Patent Document 1 below.

[0003] The lighting fixture of Patent Document 1 below includes a substrate on which a light source is mounted, a heat sink on which the substrate is disposed, and a reflector unit. The reflector unit reflects a part of the light emitted from the light source so that a predetermined light distribution pattern is formed. Further, the substrate is fixed to the heat sink by the reflector unit pressing a plurality of portions of the substrate and pressing the substrate against the heat sink.

[0004] Furthermore, the lamp described in Patent Document 1 below is a vehicle headlight and comprises a first light source, a second light source positioned below the first light source, a reflector unit positioned in front of the substrate, and a projection lens positioned in front of the reflector unit. The reflector unit has a first reflector positioned between the first light source and the second light source, and a pair of second reflectors positioned above and below the first reflector. A portion of the light emitted from the first light source passes between the first reflector and the upper second reflector and directly enters the projection lens, another portion of the light is reflected toward the projection lens by the upper surface of the first reflector, and yet another portion of the light is reflected toward the projection lens by the upper second reflector. In this way, the light emitted from the first light source and entering the projection lens forms a low beam light distribution pattern having a cutoff line corresponding to the shape of the front end of the first reflector. Furthermore, a portion of the light emitted from the second light source passes between the first reflector and the lower second reflector and directly enters the projection lens, another portion of that light is reflected toward the projection lens by the lower surface of the first reflector, and yet another portion of that light is reflected toward the projection lens by the lower second reflector. In this way, the light emitted from the second light source and entering the projection lens forms an additional light distribution pattern, and the high beam light distribution pattern is formed by this additional light distribution pattern and the low beam light distribution pattern. For this reason, this vehicle headlight can switch between low beam and high beam by switching the emission and non-emission of light from the second light source.

[0005] Furthermore, there are vehicle headlights that include a light source, a projection lens that transmits the emitted light to irradiate the desired light, and a lens holder that holds the projection lens. Such a vehicle headlight is disclosed in Patent Document 2 below. In this vehicle headlight, the lens holder is made of resin, and a light-shielding portion is provided between the projection lens and the lens holder to prevent damage to the lens holder caused by sunlight entering the vehicle headlight through the projection lens focusing onto the lens holder.

[0006] Furthermore, some vehicle headlights have a substrate on which the light source is mounted, which is placed on a heat sink, so that the heat generated from the light source is released from the heat sink. Such a vehicle headlight is disclosed in Patent Document 3 below. In this vehicle headlight, a substrate on which an array of light-emitting diodes (LEDs) is mounted is placed on a heat sink. Specifically, the back surface of the substrate where the light-emitting diode array is mounted is placed on the substrate mounting surface of the heat sink, which is formed in a convex shape. Therefore, the heat generated from the light-emitting diode array is conducted from the light-emitting diode array through the substrate to the heat sink and released from the heat sink.

[0007] [Patent Document 1] International Publication No. 2019 / 177050 [Patent Document 2] Japanese Patent Publication No. 2017-45616 [Patent Document 3] International Publication No. 2016 / 013447 [Overview of the Initiative]

[0008] A luminaire according to a first aspect of the present invention comprises a substrate on which a light source is mounted, a heat sink on which the substrate is placed, and a reflector unit that presses the substrate against the heat sink and reflects a portion of the light emitted from the light source, wherein the substrate has recesses on opposite sides, the light source is located inside the bottom of each of the recesses, and the reflector unit presses against the portion of the substrate outside the bottom of each of the recesses.

[0009] In the first embodiment of this luminaire, as described above, the substrate has recesses on opposite sides. Therefore, the strength of the parts of the substrate outside the bottom of each recess is weaker than in the case where the substrate does not have recesses, and the reflector unit presses on these weakened parts. Therefore, with the first embodiment of this luminaire, the distortion of the substrate due to the pressing force of the reflector unit can be concentrated on the weakened parts, and the distortion inside the bottom of the recess can be reduced compared to the above case. Also, in the first embodiment of this luminaire, as described above, the light source is located inside the bottom of the recess. Therefore, with this luminaire, the change in the direction of the light source due to the distortion of the substrate can be suppressed compared to the above case, and a predetermined light distribution pattern can be easily formed. Also, in the first embodiment of this luminaire, the reflector unit presses on one recess side and the other recess side of the substrate. Therefore, according to the first embodiment of this luminaire, compared to the case where the reflector unit presses only on one recessed side of the substrate, it is possible to suppress the shift in the relative position between the substrate and the heat sink, and it is easier to form a predetermined light distribution pattern.

[0010] In the first embodiment of the lamp, the reflector unit may press both sides of each of the recesses on the substrate.

[0011] With this configuration, it is possible to suppress the shift in the relative position between the substrate and the heat sink, compared to the case where the reflector unit presses only one side of each recess on the substrate.

[0012] In the first embodiment of the light fixture, the heat sink may have protrusions that are inserted into each of the recesses.

[0013] With this configuration, the positioning of the substrate relative to the heat sink can be determined by the side surface of the substrate that defines the recess and the outer surface of the projection.

[0014] In the first embodiment of the luminaire, the reflector unit has a flat opposing surface facing the substrate and an opening that penetrates from the opposing surface to the surface opposite to the substrate, and the light source may overlap the opening.

[0015] This configuration makes it easier to form the opposing surfaces by machining, for example, compared to the case where the opposing surfaces are not flat.

[0016] In this case, the opposing surface may extend to the outer edge of the substrate-side surface of the reflector unit.

[0017] This configuration makes it easier to form the opposing surfaces mentioned above by machining, for example.

[0018] The luminaire according to the first embodiment described above further comprises a connector mounted on the substrate, and the reflector unit may not be formed on the side of the connector opposite to the light source.

[0019] This configuration makes it easier to connect other connectors to the connector compared to when the reflector unit is formed on the opposite side of the connector from the light source.

[0020] A vehicle headlight according to a second aspect of the present invention comprises: a first light source that emits light from a planar emitting surface to form a low beam light distribution pattern; a second light source located below the first light source and emitting light from a planar emitting surface to form a high beam light distribution pattern together with the light emitted from the first light source; a substrate on which the first light source and the second light source are mounted; a reflector unit positioned in front of the substrate; and a projection lens positioned in front of the reflector unit, wherein the reflector unit has a first reflector positioned between the first light source and the second light source and having reflective surfaces on both its upper and lower surfaces, and a pair of second reflectors positioned above and below the first reflector, wherein the perpendicular line of the emitting surface of one of the first and second light sources moves away from the first reflector in the forward direction, and the perpendicular line of the emitting surface of the other light source moves closer to the first reflector in the forward direction. The present invention is characterized in that, of the light emitted from one light source, some of the light passes between one reflective surface of the first reflector and one second reflector and is directly incident on the projection lens, another portion of the light is reflected toward the projection lens at the portion of the one reflective surface of the first reflector including the front end, and yet another portion of the light is reflected by the one second reflector and is reflected toward the projection lens at the portion of the one reflective surface of the first reflector including the front end, and of the light emitted from the other light source, some of the light passes between the other reflective surface of the first reflector and the other second reflector and is directly incident on the projection lens, another portion of the light is reflected toward the projection lens at the portion of the other reflective surface of the first reflector including the front end, and yet another portion of the light is reflected toward the projection lens by the other second reflector.

[0021] In the second embodiment of this vehicle headlight, the first and second light sources are mounted on a common substrate, thus reducing the number of components compared to the case where the first and second light sources are mounted on different substrates. Furthermore, in the second embodiment of this vehicle headlight, the perpendicular line to the emission surface of one of the first and second light sources differs from the perpendicular lines to the emission surfaces of the first and second light sources in the first patent document, as it is set away from the first reflector in the forward direction. As a result, the amount of light emitted from one light source and directly incident on the front end of one reflective surface of the first reflector tends to be small, making it difficult to brighten that front end. However, along with this light, light emitted from one light source and reflected by the second reflector also enters the front end of one reflective surface of the first reflector, and these lights are reflected toward the projection lens. Therefore, even with such a single light source, it is possible to suppress the darkening of the front end of one reflective surface, which is either the upper or lower surface of the first reflector. Furthermore, since the perpendicular line from the emission surface of the other light source approaches the first reflector toward the front, the light from the other light source can brighten the front end of the other reflective surface, which is the upper or lower surface of the first reflector. For this reason, the vehicle headlight in the second embodiment can suppress the darkening of the front end of the upper and lower surfaces of the first reflector. Accordingly, the vehicle headlight in the second embodiment can suppress the darkening of the vicinity of the cutoff line in the low beam light distribution pattern and the vicinity of the center of the high beam light distribution pattern, thereby suppressing a decrease in visibility.

[0022] In the vehicle headlight of the second embodiment, the one light source may be the first light source.

[0023] In the second embodiment of the vehicle headlight, some of the light emitted from the one light source may be reflected toward the first reflector at the first second reflector with a divergence angle smaller than that at the incident light.

[0024] According to such a configuration, when the one light source described above is the first light source, it is possible to further suppress the vicinity of the cut-off line in the light distribution pattern of the low beam from becoming dark, and when the one light source described above is the second light source, it is possible to further suppress the vicinity of the center in the light distribution pattern of the high beam from becoming dark.

[0025] In the vehicle headlamp according to the second aspect, a part of the light emitted from the other light source may be reflected toward the projection lens with a divergence angle larger than when it enters the other second reflector.

[0026] According to such a configuration, when the one light source described above is the first light source, it is possible to easily expand the light distribution pattern of the high beam upward, and when the one light source described above is the second light source, it is possible to easily expand the light distribution pattern of the low beam downward.

[0027] The vehicle headlamp according to the second aspect described above may further include an integrated circuit mounted on the substrate and configured to adjust the power supplied to at least one of the first light source and the second light source, and the reflector unit may have a cover portion that covers the integrated circuit.

[0028] By adopting such a configuration, it is possible to suppress sunlight or the like incident from the outside through the projection lens from irradiating the integrated circuit.

[0029] The vehicle headlamp according to the third aspect of the present invention includes a light source, a reflector unit having a reflecting portion that reflects the light emitted from the light source forward and downward forward, a projection lens through which the light reflected by the reflecting portion passes, and a conductive member disposed below the reflecting portion. The reflector unit is integrally formed with the reflecting portion and has a light-shielding cover positioned between the projection lens and the conductive member below the reflecting portion.

[0030] According to the third embodiment of this vehicle headlight, a light-shielding member is placed between the conductive member and the projection lens, thereby suppressing the irradiation of the conductive member by sunlight incident through the projection lens. Furthermore, the reflective part that reflects the light emitted from the light source usually has light-shielding properties. Therefore, by integrating the light-shielding cover and the reflective part, both of which have light-shielding properties, it is possible to suppress damage to the conductive member by sunlight at a low cost.

[0031] Furthermore, the vehicle headlight of the third embodiment described above further comprises a lens holder that holds the projection lens and has a bottom plate portion extending from the light-shielding cover side toward the projection lens side, wherein the light-shielding cover includes a plate-shaped cover portion extending along the direction of extension of the bottom plate portion, and preferably at least a part of the side surface of the plate-shaped cover portion overlaps with the bottom plate portion in the direction of extension.

[0032] If the plate-shaped cover portion does not overlap with the base plate portion in the extending direction, and the plate-shaped cover portion is located below the base plate portion, sunlight propagating toward the plate-shaped cover portion may damage the lens holder. If the plate-shaped cover portion rests on the base plate portion, sunlight propagating toward the plate-shaped cover portion may be reflected by the entire side surface of the plate-shaped cover portion, and the reflected light may damage the lens holder. For this reason, as described above, by having at least a portion of the side surface of the plate-shaped cover portion overlap with the base plate portion in the extending direction, damage to the lens holder by sunlight propagating toward the plate-shaped cover portion can be suppressed.

[0033] Preferably, the width of the bottom plate portion in the left-right direction is greater than that of the plate-shaped cover portion, and a recess is formed on the edge of the bottom plate portion on the plate-shaped cover portion side into which a part of the plate-shaped cover portion fits.

[0034] A portion of the plate-shaped cover fits into a recess in the bottom plate, which helps to suppress lateral misalignment between the reflector unit and the lens holder.

[0035] Furthermore, it is preferable that the upper surface of the plate-shaped cover portion scatters and reflects the incident light.

[0036] In this case, sunlight propagating through the plate-shaped cover is scattered, which can prevent the sunlight from being reflected and damaging other components.

[0037] Furthermore, it is preferable that the light-shielding cover has a light-scattering portion between the reflective portion and the plate-shaped cover portion that scatters and reflects incident light.

[0038] Depending on the placement of the conductive members, the plate-shaped cover portion and the reflective portion may be separated. With the above configuration, sunlight propagating between the plate-shaped cover portion and the reflective portion is scattered, thereby suppressing damage to other components caused by the reflection of that sunlight.

[0039] In this case, it is preferable that the width of the plate-shaped cover portion in the left-right direction is greater than the width of the light-scattering portion in the left-right direction, and that each of the left and right ends of the plate-shaped cover portion extends further back than the light-scattering portion.

[0040] This configuration allows for a wider range of conductive members that can be protected by the plate-shaped cover.

[0041] Furthermore, it is preferable that the light-shielding cover has side cover portions extending rearward and upward from the rear end of each of the aforementioned ends.

[0042] This configuration allows for an even wider range of conductive components that can be protected by the light-shielding cover.

[0043] A vehicle headlight according to a fourth aspect of the present invention comprises a substrate on which a light source and an integrated circuit for switching the power supply to the light source are mounted, and a heat sink on which the substrate is arranged, wherein the substrate-facing region of the heat sink facing the substrate includes a separation portion spaced apart from the substrate and an arrangement portion formed convexly toward the substrate side than the separation portion and on which the substrate is arranged, and the arrangement portion includes a light source-facing region facing the back surface of the region on which the light source is mounted on the substrate, an integrated circuit-facing region facing the back surface of the region on which the integrated circuit is mounted on the substrate, and a first connecting region connecting the light source-facing region and the integrated circuit-facing region.

[0044] In this fourth embodiment of the vehicle headlight, the heat generated from the light source and the integrated circuit is conducted through the substrate, mainly from the region facing the light source and the region facing the integrated circuit to the heat sink, and dissipated. However, when the heat generated from the light source and the integrated circuit is conducted through the substrate, the region of the substrate between the region on which the light source is mounted and the region on which the integrated circuit is mounted may be heated. In the above vehicle headlight, the heat in this region can be conducted from the first connecting region to the heat sink and dissipated. In addition, by having a separation portion, it is possible to suppress the unnecessary return of heat conducted to the heat sink from the heat sink to the substrate. Therefore, the above fourth embodiment of the vehicle headlight can efficiently dissipate heat.

[0045] Furthermore, the light source may include a plurality of light-emitting elements arranged in parallel with each other, the region facing the light source may extend along the parallel direction of the plurality of light-emitting elements, and the region facing the integrated circuit may coincide with a straight line perpendicular to the line segment connecting the light-emitting elements located at both ends.

[0046] With this configuration, the extension direction of the region facing the light source and the extension direction of the region including the integrated circuit facing region and the first connecting region can be orthogonal to each other. Therefore, the substrate can be stably placed on the heat sink.

[0047] Furthermore, it is preferable that the separation portions be located on both sides of the first connecting region in the parallel direction.

[0048] By adopting this configuration, it is possible to further suppress the return of heat conducted to the heat sink to the substrate compared to the case where there are no separated sections on both sides of the first connecting region.

[0049] Furthermore, it is preferable that the arrangement portion includes an adjustment region extending in the parallel direction with a width wider than the integrated circuit facing region, on the side opposite to the light source facing region with respect to the integrated circuit facing region, and a second connecting region connecting the adjustment region and the integrated circuit facing region.

[0050] In this case, the substrate can be stably positioned by a heat sink by sandwiching the integrated circuit-facing region between the light source-facing region and the adjustment region, which extend in the same direction. [Brief explanation of the drawing]

[0051] [Figure 1] This figure schematically shows a lighting fixture in the first embodiment as the first and second embodiments of the present invention. [Figure 2] This is an exploded perspective view of the lighting unit, seen from the front and slightly above. [Figure 3] This is an exploded perspective view of the lighting unit, seen from the rear and slightly downward. [Figure 4] This is a vertical cross-sectional view of the lighting unit. [Figure 5] This is a perspective view of the heatsink from the front and slightly above. [Figure 6] This is a schematic front view of the circuit board. [Figure 7] This is a front view showing the reflector unit attached to the heatsink, seen from the front. [Figure 8] This figure shows a magnified view of the area including the light distribution forming section in Figure 7. [Figure 9] This figure shows a magnified view of the area including the light distribution formation section in Figure 4. [Figure 10] This is a view of the back of the heatsink. [Figure 11] This figure is an enlarged portion of Figure 4, schematically showing examples of the optical paths of light emitted from the first light source and light emitted from the second light source. [Figure 12] This figure shows the light distribution pattern of the low beam in the first embodiment. [Figure 13] This figure shows the light distribution pattern of the high beam in the first embodiment. [Figure 14] This figure shows the reflector unit in the first modified example, as a first embodiment, attached to the heat sink, similar to Figure 7. [Figure 15] This figure shows the lighting unit in the first modified example in the same way as in Figure 4. [Figure 16] This figure shows an example of the optical path of light emitted from the first light source and light emitted from the second light source in a second modified example as a second embodiment, similar to Figure 11. [Figure 17] This is a schematic diagram showing a vehicle headlight in a second embodiment, which is a third aspect of the present invention. [Figure 18] Figure 17 is an exploded perspective view of the lighting unit. [Figure 19] This is an enlarged view of the reflector unit in the second embodiment. [Figure 20] This is a perspective view of the lighting unit in the second embodiment with the projection lens removed. [Figure 21] This is a vertical cross-sectional view of the lighting unit in the second embodiment. [Figure 22] This is a perspective view of the lighting unit in the second embodiment with the projection lens, lens holder, and reflector unit removed. [Figure 23] This is a schematic diagram showing a vehicle headlight in a third embodiment, which is a fourth aspect of the present invention. [Figure 24] Figure 23 is an exploded perspective view of the lighting unit. [Figure 25] This is a front view of the substrate in the third embodiment. [Figure 26] This is a front view of the heat sink in the third embodiment. [Figure 27] This is a vertical cross-sectional view of the lighting unit in the third embodiment. [Figure 28] This diagram shows a modified version of the circuit board. [Modes for carrying out the invention]

[0052] The following examples illustrate embodiments of the lighting fixture and vehicle headlight according to the present invention, along with the accompanying drawings. The embodiments illustrated below are provided to facilitate understanding of the present invention and are not intended to limit its interpretation. The present invention can be modified and improved without departing from its spirit. Furthermore, the components of each embodiment illustrated below may be combined as appropriate. Note that in the drawings referenced below, the dimensions of each component may be shown differently for the sake of clarity.

[0053] (First Embodiment) A first embodiment of the present invention, as a first and second embodiment, will be described below. Figure 1 is a schematic diagram showing a lamp in this embodiment, and is a schematic diagram showing a vertical cross-section of the lamp. The lamp in this embodiment is a vehicle headlight, and is for automobiles. Vehicle headlights are generally installed on the left and right sides of the front of the vehicle. In this specification, "right" means the right side in the direction of travel of the vehicle, and "left" means the left side in the direction of travel of the vehicle. The left and right vehicle headlights have the same configuration, except that their shape is generally symmetrical in the left-right direction. For this reason, one of the vehicle headlights will be described below.

[0054] As shown in Figure 1, the vehicle headlight 1 of this embodiment mainly comprises a housing 10 and a lighting unit LU. Figure 1 is a side view of the vehicle headlight 1, and for ease of understanding, the housing 10 is shown in cross-section in Figure 1.

[0055] The housing 10 includes a lamp housing 11 and a light-transmitting front cover 12. The front of the lamp housing 11 is open, and the front cover 12 is fixed to the lamp housing 11 so as to close this opening. The space formed by the lamp housing 11 and the front cover 12 is a luminaire chamber R, and a luminaire unit LU is housed in this luminaire chamber R.

[0056] Figure 2 is an exploded perspective view of the luminaire unit LU viewed from the front and diagonally above. Figure 3 is an exploded perspective view of the luminaire unit LU viewed from the rear and diagonally below. Figure 4 is a vertical cross-sectional view of the luminaire unit LU. As shown in Figures 1 to 4, the luminaire unit LU of this embodiment mainly comprises a heat sink 20, an axial flow fan 30, a circuit board 40, a reflector unit 50, a projection lens 60, and a holder 70. Note that Figure 4 is a vertical cross-sectional view of the luminaire unit LU along the optical axis of the projection lens 60, which will be described later, and the fan 30 is omitted from the description in Figure 4.

[0057] Figure 5 is a perspective view of the heat sink 20 from the front and diagonally above. The heat sink 20 is made of a material with excellent heat dissipation properties, such as metal. As shown in Figures 2 to 5, the heat sink 20 of this embodiment mainly comprises a base plate 21 on which the substrate 40 is placed, a plurality of heat dissipation fins 22, a plurality of mounting bosses 23a, 23b, and a peripheral wall portion 24.

[0058] The base plate 21 is a plate-shaped member with its front surface facing forward and its back surface facing backward, and has an inclined portion 25 that slopes upward and backward. A pedestal 25a is provided on the inclined portion 25 that protrudes forward, and the end face 25s of the pedestal 25a is a flat surface that slopes upward and backward. The substrate 40 is placed on this end face 25s. Projections 26 that protrude forward are provided on both the left and right sides of the pedestal 25a. In addition, pins 27 that protrude forward are provided on the right and left sides of the pedestal 25a on the base plate 21.

[0059] Multiple heat dissipation fins 22, mounting bosses 23a, 23b, and peripheral wall portions 24 are located on the back surface of the base plate 21 opposite to the substrate 40 side, extending towards the rear and formed integrally with the base plate 21. The fan 30 is located behind the multiple heat dissipation fins 22 and fixed to the mounting bosses 23a, 23b. The heat sink 20 is cooled by airflow from the fan 30. The back surface of the heat sink 20, where the multiple heat dissipation fins 22, mounting bosses 23a, 23b, peripheral wall portions 24, and fan 30 are located, will be described later.

[0060] The substrate 40 is a flat plate-shaped member made of, for example, metal, and as described above, is placed on the end face 25s of the base 25a of the heat sink 20. Figure 6 is a schematic front view of the substrate 40. As shown in Figure 6, in this embodiment, the outer shape of the substrate 40 is a roughly symmetrical rectangular shape, and the substrate 40 has a pair of recesses 45 in which the left and right sides 40sf, which face each other, are recessed. The recesses 45 are roughly rectangular in shape, and the sides 40sf of the substrate 40 that define the recesses 45 include a pair of straight portions 45S that extend in the left-right direction and face each other, a bottom portion 45B that is the tip in the recess direction and extends in the vertical direction, and a corner portion 45R that connects the straight portions 45S and the bottom portion 45B. The projections 26 of the heat sink 20 are inserted into each recess 45. The projections 26 are shown in Figure 6. The pair of straight sections 45S in the recess 45 and the outer circumferential surface of the projection 26 restrict the vertical movement of the substrate 40 along the end face 25s. Furthermore, the bottom 45B of one recess 45 and the outer circumferential surface of one projection 26, and the bottom 45B of the other recess 45 and the outer circumferential surface of the other projection 26, restrict the horizontal movement of the substrate 40 along the end face 25s. In this way, the recess 45 and the projection 26 restrict the movement of the substrate 40 along the end face 25s, thereby positioning the substrate 40 relative to the heat sink 20. The shape of the recess 45 is not particularly limited. The projection 26 may also be press-fitted into the recess 45.

[0061] In this embodiment, a first light source 41, a second light source 42, an integrated circuit 43, and a connector 44 are mounted on the front surface 40f of the substrate 40.

[0062] The first light source 41 emits light from a planar emission surface that forms the low beam light distribution pattern. The second light source 42 emits light from a planar emission surface that forms the high beam light distribution pattern together with the light emitted from the first light source 41. In this embodiment, the first light source 41 and the second light source 42 are LED arrays consisting of a plurality of LEDs (Light Emitting Diodes) arranged in the left-right direction, and are positioned inward from the bottom 45B of the recess 45. In this embodiment, the second light source 42 is located below the first light source and overlaps with the recess 45 in the left-right direction, which is the direction in which the plurality of LEDs are arranged.

[0063] The integrated circuit 43 is positioned below the second light source 42, and the connector 44 is positioned below the integrated circuit 43. The substrate 40 is provided with a circuit (not shown) through which the connector 44 is connected to the first light source 41, the connector 44 to the integrated circuit 43, and the integrated circuit 43 to the second light source 42. Power is supplied to the connector 44 from a power supply unit (not shown). As a result, power is supplied from the connector 44 to the first light source 41, and from the connector 44 to the second light source 42 via the integrated circuit 43. The integrated circuit 43 includes multiple switch elements and can individually adjust the power supplied to each LED of the second light source 42. The integrated circuit 43 only needs to be able to adjust the power supplied to at least one of the first light source 41 and the second light source 42, and its configuration is not particularly limited. The arrangement of the integrated circuit 43 and the connector 44 is also not particularly limited. Furthermore, the integrated circuit 43 does not need to be mounted on the substrate 40; in this case, the connector 44 and the second light source 42 are connected by a circuit.

[0064] When the substrate 40 is viewed from the front, the areas on the substrate 40 where the first light source 41, the second light source 42, and the integrated circuit 43 are mounted coincide with the end face 25s. Also, as described above, since the end face 25s is tilted upwards toward the rear, the substrate 40 is tilted similarly, and the front surface 40f faces diagonally upwards and forwards. The perpendicular line 41L of the emission surface of the first light source 41 and the perpendicular line 42L of the emission surface of the second light source 42 are approximately perpendicular to the front surface 40f of the substrate 40. For this reason, the perpendicular lines 41L and 42L face diagonally upwards and forwards. The perpendicular lines 41L and 42L shown in Figure 4 are the same as straight lines that pass through the center of the emission surface, are parallel to the emission direction of the light with the strongest intensity emitted from the light source, and pass through the area on the emission surface from which that light is emitted.

[0065] Figure 7 is a front view of the reflector unit 50 attached to the heat sink 20, viewed from the front, and is a view along the optical axis of the projection lens 60, which will be described later. As shown in Figures 4 and 7, the reflector unit 50 is positioned in front of the substrate 40, and the substrate 40 is sandwiched between the reflector unit 50 and the heat sink 20. The reflector unit 50 in this embodiment consists of a light distribution forming section 50a and cover sections 50b connected to both the left and right sides and below the light distribution forming section 50a, and the light distribution forming section 50a and the cover sections 50b are integrally formed. In Figure 7, the light distribution forming section 50a is surrounded by a dashed line. In this embodiment, the reflector unit 50 is fixed to the heat sink 20 by fixing the cover section 50b to the heat sink 20 with screws 80. Examples of materials that make up the reflector unit 50 include plated metal, and the reflector unit 50 is formed, for example, by machining and plating a metal member obtained by casting.

[0066] Figure 8 is a magnified view of the area including the light distribution forming section 50a in Figure 7, and Figure 9 is a magnified view of the area including the light distribution forming section 50a in Figure 4. As shown in Figures 8 and 9, the light distribution forming section 50a of this embodiment mainly consists of a first reflector 51, a pair of second reflectors 52a, 52b, a pair of upper side reflectors 53a, 53b, and a pair of lower side reflectors 54a, 54b.

[0067] The first reflector 51 is positioned between the first light source 41 and the second light source 42 and extends in the front-rear direction. The first reflector 51 has a tapered shape toward its front end 51e, and its upper and lower surfaces are reflective surfaces 51ur and 51dr that reflect light. In this embodiment, the upper reflective surface 51ur is located below the perpendicular line 41L of the first light source 41 and curves downward in a concave shape. The lower reflective surface 51dr is located above the perpendicular line 42L of the second light source 42 and curves upward in a concave shape. Furthermore, the front end 51e of the first reflector 51 has a shape that matches the cutoff line in the low beam light distribution pattern described later, and is gradually concave backward from the left and right ends toward the center. As described above, since the perpendicular line 41L of the first light source 41 and the perpendicular line 42L of the second light source 42 point diagonally upward and forward, the perpendicular line 41L moves away from the first reflector 51 in the forward direction, and the perpendicular line 42L moves closer to the first reflector 51 in the forward direction.

[0068] The second reflector 52a is positioned above the first reflector 51 and has a reflective surface 52ar on the side facing the first reflector 51. In this embodiment, the second reflector 52a is a plate-shaped member, and the side surface of the plate-shaped member is the reflective surface 52ar. This reflective surface 52ar and the reflective surface 51ur on the upper side of the first reflector 51 extend along the parallel direction of the plurality of LEDs constituting the first light source 41, forming a pair of reflectors positioned to sandwich the plurality of LEDs from above and below.

[0069] The other second reflector 52b is positioned below the first reflector 51 and has a reflective surface 52br on the side facing the first reflector 51. In this embodiment, the second reflector 52b is a plate-shaped member, and one of the main surfaces of the plate-shaped member is the reflective surface 52br. This reflective surface 52br and the lower reflective surface 51dr of the first reflector 51 extend along the parallel direction of the plurality of LEDs constituting the second light source 42, forming a pair of reflectors positioned to sandwich the plurality of LEDs from above and below.

[0070] One upper side reflector 53a is formed at one end of the space between the upper reflective surface 51ur of the first reflector 51 and the reflective surface 52ar of one of the second reflectors 52a, in the parallel direction of the multiple LEDs constituting the first light source 41. The other upper side reflector 53b is formed at the other end of the same space. The pair of upper side reflectors 53a and 53b are formed such that the distance between them increases from rear to front. An opening 55 is formed in the light distribution forming section 50a, surrounded by this pair of upper side reflectors 53a and 53b, the first reflector 51, and the second reflector 52a, and the emission surface 41s of the first light source 41 overlaps with the opening 55 in a front view. Note that in Figure 8, for ease of viewing, one first light source 41 and emission surface 41s are labeled with reference numerals, while the reference numerals for the others are omitted.

[0071] One lower side reflector 54a is formed at one end of the space between the lower reflective surface 51dr of the first reflector 51 and the reflective surface 52br of the other second reflector 52b, in the parallel direction of the multiple LEDs constituting the second light source 42. The other lower side reflector 54b is formed at the other end of the same space. The pair of lower side reflectors 54a and 54b are formed such that the distance between them increases from rear to front. An opening 56 is formed in the light distribution forming section 50a, surrounded by this pair of lower side reflectors 54a and 54b, the first reflector 51, and the second reflector 52b, and the emission surface 42s of the second light source 42 overlaps with the opening 56 in a front view. Note that in Figure 8, for ease of viewing, one second light source 42 and emission surface 42s are labeled with reference numerals, while the reference numerals for the others are omitted. Furthermore, the opening 56 and the opening 55 penetrate from a flat opposing surface 50as in the light distribution forming section 50a that is generally parallel to the substrate 40, to the surface opposite to the substrate 40. Note that the opposing surface 50as does not have to be flat.

[0072] In this embodiment, through holes 57 are provided on both the left and right sides of the cover portion 50b, and the pins 27 of the heat sink 20 are inserted into these through holes 57. Therefore, the circumferential surface defining the through holes 57 and the pins 27 allow the reflector unit 50 to be positioned relative to the heat sink 20. Also, as shown in Figure 4, the integrated circuit 43 and connector 44 and the cover portion 50b overlap in a direction perpendicular to the front surface 40f of the substrate 40. Therefore, when the substrate 40 is viewed from above, the cover portion 50b covers the integrated circuit 43 and connector 44 mounted on the substrate 40. Also, as shown in Figure 3, the light distribution forming portion 50a and the cover portion 50b are provided with a plurality of ribs 58 that protrude toward the rear. When the reflector unit 50 is fixed to the heat sink 20, the tips of the ribs 58 abut against the front surface 40f of the substrate 40, and the substrate 40 is pressed against the heat sink 20 by the reflector unit 50 and fixed to the heat sink 20.

[0073] In Figure 6, the areas 46a, 46b, 46c, and 46d that the reflector unit 50 presses against the substrate 40 are indicated by hatched lines. In this embodiment, the reflector unit 50 presses against four areas 46a, 46b, 46c, and 46d, with areas 46a and 46b located outside the bottom 45B of one recess 45, and areas 46c and 46d located outside the bottom 45B of the other recess 45. Therefore, the reflector unit 50 presses against the areas on the substrate 40 that are outside the bottom 45B of each recess 45. Furthermore, areas 46a and 46b are located above and below one recess 45, respectively, and sandwich this one recess 45 in a direction along the side surface 40sf. Furthermore, parts 46c and 46d are located above and below the other recess 45, respectively, and sandwich this other recess 45 in a direction along the side surface 40sf. As a result, the reflector unit 50 presses both sides of each recess 45 on the substrate 40. In addition, the outer shape of parts 46a, 46b, 46c, and 46d is generally rectangular, but is not particularly limited.

[0074] The projection lens 60 is a lens that changes the divergence angle of transmitted light and is positioned in front of the reflector unit 50. In this embodiment, the projection lens 60 is a biconvex aspherical lens with an outer shape that is elongated in the left-right direction and is generally oval-track shaped. The outer surface of the projection lens 60 is provided with a flange portion 61 that protrudes outward and extends around the entire circumference. The optical axis 60c of the projection lens 60 extends in the front-rear direction, intersects with the first reflector 51, and passes between the first light source 41 and the second light source 42. The rear focal point 60f of the projection lens 60 is located near the front end 51e of the first reflector 51 and the projection lens 60, and the vicinity of the front end 51e is, for example, a position where the distance to the front end 51e is 10 mm or less. The focal point 60f may be located at the front end 51e or may overlap with the first reflector 51. Examples of materials that make up the projection lens 60 include resin and glass.

[0075] As shown in Figures 1 to 3, the holder 70 of this embodiment consists of a cylindrical support portion 71 extending in the front-rear direction and a pair of feet 72 extending rearward from both the left and right sides of the rear end of the support portion 71. A plurality of bases 73 projecting forward are provided at the front end of the support portion 71, and the flange portion 61 of the projection lens 60 is fixed to the bases 73 by means of ultrasonic welding or laser welding, for example. The feet 72 are fixed to the heat sink 20 by screws 81, and the projection lens 60 is fixed to the heat sink 20 via the holder 70. As a material for constituting the holder 70, for example, an opaque resin such as polycarbonate can be used, and in this embodiment, the support portion 71 and the feet 72 are integrally formed.

[0076] Next, we will describe the back side of heatsink 20.

[0077] Figure 10 is a rear view of the heat sink 20. The multiple heat dissipation fins 22 of the heat sink 20 are arranged in parallel with spacing between them and extend in the left-right direction. In each figure, for ease of viewing, only one heat dissipation fin 22 and one of the gaps 500 between adjacent heat dissipation fins 22 are labeled. In Figure 10, the uppermost heat dissipation fin 22 is referred to as heat dissipation fin 22a, and the lowermost heat dissipation fin is referred to as heat dissipation fin 22b. Unless otherwise specified, heat dissipation fin 22 refers to heat dissipation fins 22a, 22b and the heat dissipation fins located between heat dissipation fins 22a, 22b and extending in the left-right direction.

[0078] The left and right sides of the heat dissipation fin 22 and the area above the heat dissipation fin 22a are surrounded by a peripheral wall portion 24. The peripheral wall portion 24 is a frame that surrounds the heat dissipation fin 22 as described above, and is separate from the heat dissipation fin 22. In the front-rear direction, the left and right walls of the peripheral wall portion 24 are shorter than the heat dissipation fin 22, and the upper wall is longer than the heat dissipation fin 22.

[0079] As shown in Figures 2, 3, and 10, a fan 30 is provided behind the multiple heat dissipation fins 22. The fan 30 mainly consists of an impeller 31 provided on the side opposite to the base plate 21 relative to the multiple heat dissipation fins 22, and a support unit 33. For ease of viewing, the impeller 31 is not shown in Figures 2 and 3. Figure 10 is also a view along the rotation axis R1 of the impeller 31. The impeller 31 and the support unit 33 are each made of, for example, resin.

[0080] The impeller 31 rotates around a rotation axis R1 that is perpendicular to the back surface of the base plate 21. The impeller 31 also rotates along the back surface of the base plate 21 to blow air into the gaps 500 between adjacent heat dissipation fins 22. In this embodiment, the impeller 31 rotates counterclockwise. The impeller 31 is rotatably supported by a support unit 33.

[0081] The support unit 33 mainly comprises a base member 33a on which the impeller 31 is arranged, and a support member 33b provided to the side of the impeller 31 and the base member 33a when the fan 30 is viewed from the rear.

[0082] The base member 33a is a circular plate-like member positioned in front of the impeller 31. For clarity, the base member 33a is not shown in Figure 10. The base member 33a is connected to the support member 33b via spokes 33c that are connected to the outer circumferential surface of the base member 33a and the inner circumferential surface of the support member 33b. Therefore, the support member 33b rotatably supports the impeller 31 via the base member 33a and the spokes 33c. For clarity, the spokes 33c are not shown in Figure 10.

[0083] The support member 33b is an outer frame that surrounds the sides of the impeller 31 and the base member 33a, and is formed in a generally square shape. In this embodiment, two generally parallel sides of the generally square support member 33b are aligned in the left-right direction. The support member 33b is shorter than the heat dissipation fins 22 in the left-right direction and longer than the distance between the heat dissipation fins 22a and 22b in the up-down direction. The front surfaces of the base member 33a and the support member 33b are in contact with the rear ends of the heat dissipation fins 22, but may be separated from the rear ends. The four corners of the support member 33b are rounded.

[0084] Through holes 33d are provided in the upper right and lower left corners of the support member 33b, and screws 501 are inserted into the through holes 33d, which are then screwed into the mounting bosses 23a and 23b. In this way, the fan 30 is attached to the heatsink 20 via the support member 33b and the mounting bosses 23a and 23b.

[0085] Next, the positions of the mounting bosses 23a and 23b will be explained using Figure 10. In Figure 10, the mounting bosses 23a and 23b are hidden by the fan 30 and are not visible, but they are shown with dashed lines for easier understanding.

[0086] In Figure 10, a straight line passing through the rotation axis R1 and extending in the direction of the heat dissipation fin 22 is shown as the first reference line 503a, and a straight line passing through the rotation axis R1 and extending perpendicular to the first reference line 503a is shown as the second reference line 503b. Four regions are formed by the reference lines 503a and 503b, and the upper right, upper left, lower left, and lower right regions with respect to the rotation axis R1 are shown as regions 510a, 510b, 510c, and 510d, respectively. For ease of viewing, each region is shown slightly offset from the reference lines 503a and 503b. When viewing the fan 30 from the rear, regions 510a and 510b, and regions 510c and 510d are adjacent regions in the direction of the heat dissipation fin 22. Furthermore, since the impeller 31 rotates counterclockwise, region 510a in regions 510a and 510b, and region 510c in regions 510c and 510d, are the regions on the rear side in the direction of rotation of the impeller 31. In the heat sink 20, the mounting boss 23a is provided in the rear region 510a, and the mounting boss 23b is provided in the rear region 510c. Therefore, the mounting bosses 23a and 23b are provided in the rear regions 510a and 510c, respectively. Note that it is sufficient that at least a part of the mounting boss 23a is provided in the rear region 510a, and at least a part of the mounting boss 23b is provided in the rear region 510c.

[0087] As described above, the support member 33b is attached to the mounting bosses 23a and 23b. Therefore, when viewing the fan 30 from the rear, the mounting bosses 23a and 23b are located to the sides of the impeller 31. Furthermore, since through holes 33d are provided in the upper right and lower left corners of the support member 33b, an example is shown where the mounting boss 23a overlaps the upper right corner and the mounting boss 23b overlaps the lower left corner. The mounting boss 23a is located between the first reference line 503a and the heat dissipation fin 22a furthest upward from the first reference line 503a, specifically in the gap 500 between the heat dissipation fin 22a and the heat dissipation fin 22 adjacent to it. The mounting boss 23b is located on the outside of the heat dissipation fin 22b on the opposite side of the gap 500. The mounting bosses 23a and 23b, positioned as described above, do not overlap each other along the extending direction of the heat dissipation fin 22. Mounting boss 23a is connected to heat sink fin 22a and heat sink fin 22 adjacent to heat sink fin 22a, and mounting boss 23b is connected to heat sink fin 22b. Note that mounting bosses 23a and 23b may be connected to at least one of the adjacent heat sink fins 22 that form a gap 500, or they may be separated from the heat sink fins 22.

[0088] In Figure 10, between the first reference line 503a and the heat dissipation fin 22a furthest upward from the first reference line 503a, the region that overlaps with the region 510b on the front side in the direction of rotation of the impeller 31 between adjacent regions 510a and 510b in the direction of extension of the heat dissipation fin 22 is shown as a predetermined region 520a. When the fan 30 is viewed from the rear, some of the LEDs of the first light source 41 overlap with the predetermined region 520a. At least one LED of the first light source 41 may overlap with at least a portion of the predetermined region 520a. Most of the air flowing through the gap 500 flows toward the edge of the gap 500 that overlaps with the region 510b described above, due to the influence of airflow vortices caused by the rotation of the impeller 31. Therefore, the predetermined region 520a is more easily cooled than the region outside the predetermined region 520a, and the heat generated by the first light source 41 overlapping the predetermined region 520a is easily transferred to the heat dissipation fins 22. In the above explanation, the predetermined region 520a was used, but even if the first light source 41 overlaps the predetermined region 520b as described above, the heat generated by the first light source 41 is easily transferred to the heat dissipation fins 22. The predetermined region 520b is the region between the first reference line 503a and the heat dissipation fin 22b furthest downward from the first reference line 503a, and overlaps with the region 510d on the front side in the direction of rotation of the impeller 31 between adjacent regions 510c and 510d in the direction of extension of the heat dissipation fins 22. The first light source 41 may overlap both the predetermined regions 520a and 520b. In the above explanation, the first light source 41 was used, but the second light source 42 may overlap the predetermined regions 520a and 520b in the same way as the first light source 41.

[0089] Incidentally, structures 600 other than the heatsink 20 and fan 30 are arranged on the back side of the base plate 21. Structure 600 includes a conductive member 601 that supplies power to the fan 30, and the conductive member 601 includes power supply side wiring 605 including a connector 603.

[0090] The fan-side connector 35a of the fan-side wiring 35 extending from the fan 30 is connected to the connector 603. The connector 603 is also fixed to the back surface of the base plate 21 between the left wall of the peripheral wall portion 24 and the heat dissipation fin 22.

[0091] A portion of the power supply wiring 605 is supported by a clamp 630. The clamp 630 includes a holding portion 631 and a hooking portion 633. The holding portion 631 is generally concave when viewed from the rear of the fan 30 and is connected to the hooking portion 633. The hooking portion 633 hooks onto the receiving member 22c by sandwiching the left and right surfaces of the receiving member 22c located in region 510d. The receiving member 22c is a plate-shaped member and is provided on the back surface of the base plate 21. The receiving member 22c is connected to the side of the heat dissipation fin 22b opposite to the gap 500 side. The receiving member 22c may also dissipate heat as a heat dissipation fin. The power supply wiring 605 passes through the holding portion 631 in the front-to-back direction and hooks onto the holding portion 631, thereby holding the power supply wiring 605. The power supply wiring 605 extends further rearward from the holding part 631 and is connected to a power supply unit (not shown). When the power supply unit supplies power to the fan 30 via the power supply wiring 605 and the fan wiring 35, the fan 30 rotates.

[0092] Next, the location of structure 600 will be explained. Structure 600 is located in areas 710c and 710d, excluding areas 710a and 710b, which are downwind areas of the air that passes through the gap 500 in the direction of the extension of the heat dissipation fins 22 when the fan 30 is viewed from the rear. In Figure 10, for ease of viewing, areas 710a, 710b, 710c, and 710d are shown slightly shifted from the other areas mentioned above. Areas 710a, 710b, 710c, and 710d will be explained below.

[0093] Region 710a is located above the first reference line 503a in region 510b and is the region to the left of the gap 500 between adjacent heat dissipation fins 22 and to the left of the heat dissipation fins 22. Region 710b in this embodiment is located below the first reference line 503a in region 510d and is the region to the right of the gap 500 between adjacent heat dissipation fins 22 and to the right of the heat dissipation fins 22.

[0094] Regions 710c and 710d are areas on the back side of the base plate 21 that are outside the area enclosed by the heat dissipation fins 22a and 22b, excluding regions 710a and 710b. Region 710c is the area provided above the straight line parallel to the first reference line 503a and passing through the heat dissipation fins 22a, and above region 710b. Region 710d is the area provided below the straight line parallel to the first reference line 503a and passing through the heat dissipation fins 22b, and below region 710a.

[0095] Figure 10 shows an example where the conductive member 601 and clamp 630 are located in region 710d, not in regions 710a and 710b, and are positioned so as not to overlap with the air outlets for the air flowing along the heat dissipation fins 22. The conductive member 601 and clamp 630 may also be located in region 710c. In the front-rear direction, the conductive member 601 and clamp 630 are positioned lower than the rear end of the heat dissipation fins 22. The conductive member 601 is positioned away from the heat dissipation fins 22.

[0096] Next, we will explain the airflow on the heat dissipation fins 22 when the fan 30 is driven.

[0097] When the impeller 31 blows air into the gap 500 between adjacent heat dissipation fins 22, the air hits the back surface of the base plate 21 and flows through the gap 500 along the heat dissipation fins 22. The air flowing through the gap 500 tends to flow towards the edge of the gap 500 due to the influence of airflow vortices caused by the rotation of the impeller 31. This edge overlaps with the front regions 510b and 510d.

[0098] Mounting bosses 23a and 23b are located on the side of the impeller 31 in the rear region 510a and 510c in the direction of rotation of the impeller 31. In the gap 500 where mounting boss 23a is located, the wind flows in the opposite direction from mounting boss 23a. Therefore, mounting boss 23a is positioned outside the path of the wind flowing through the gap 500, so as not to obstruct the wind. As a result, wind obstruction by mounting boss 23a is suppressed, and the wind flowing through the gap 500 where mounting boss 23a is located passes through the gap 500 and is blown out to the left side of the heat dissipation fin 22. Also, outside the heat dissipation fin 22b, the wind flows in the opposite direction from mounting boss 23b. As a result, wind obstruction by mounting boss 23b is also suppressed.

[0099] When viewing the fan 30 from the rear, in gaps 500 other than the gap 500 where the mounting boss 23a is located, air tends to blow out to the left of the heat dissipation fins 22 in gaps 500 above the first reference line 503a. Also, in gaps 500 below the first reference line 503a, air tends to blow out to the right of the heat dissipation fins 22.

[0100] The conductive member 601 and the clamp 630 are located in region 710d other than the downwind regions 710a and 710b of the air that passes through the gap 500 in the direction of extension of the heat dissipation fins 22. Therefore, the conductive member 601 and the clamp 630 are installed outside the path of the air that passes through the gap 500 and are positioned so as not to obstruct the air. As a result, the air is blown out to the side of the heat dissipation fins 22 with the obstruction of the air by these components suppressed.

[0101] Next, the formation of the low beam light distribution pattern by the vehicle headlight 1 will be explained. Figure 11 is an enlarged portion of Figure 4 and schematically shows examples of the optical paths of the light emitted from the first light source 41 and the light emitted from the second light source 42. Note that the reflection angle and refraction angle of the light shown in Figure 11 may not be accurate.

[0102] When forming the low beam light distribution pattern, light is emitted from the first light source 41. A portion of the light L1a emitted from the first light source 41 passes between the upper reflective surface 51ur of the first reflector 51 and one of the second reflectors 52a and is directly incident on the projection lens 60. Another portion of the light L1b emitted from the first light source 41 is reflected toward the projection lens 60 at the portion of the upper reflective surface 51ur of the first reflector 51 that includes the front end, and is incident on the projection lens 60. Yet another portion of the light L1c emitted from the first light source 41 is reflected by the reflective surface 52ar of one of the second reflectors 52a, is reflected toward the projection lens 60 at the portion of the upper reflective surface 51ur of the first reflector 51 that includes the front end, and is incident on the projection lens 60. As described above, the front end 51e of the first reflector 51 has a shape that matches the cutoff line, so that the light emitted from the first light source 41 that passes near the front end 51e of the first reflector 51 forms the cutoff line in the low beam light distribution pattern. Although not shown in the illustrations, a portion of the light emitted from the first light source 41 that diffuses in the left-right direction is reflected by the pair of upper side reflectors 53a and 53b and incident on the projection lens 60. In this way, the low beam light distribution pattern is formed by the light emitted from the first light source 41 that directly incident on the projection lens 60 and the light emitted from the first light source 41 that is reflected by the reflector unit 50 and incident on the projection lens 60. Light having this low beam light distribution pattern passes through the projection lens 60 and is emitted from the vehicle headlight 1 via the front cover 12. As described above, since the rear focal point 60f of the projection lens 60 is located near the front end 51e, the light distribution pattern of the low beam projected in front of the vehicle is a light distribution pattern that is inverted by the projection lens 60.

[0103] In this embodiment, the light L1a that directly enters the projection lens 60 is mainly light emitted in a direction parallel to the perpendicular line 41L. The light L1b that is reflected by the first reflector 51 and enters the projection lens 60, and the light L1c that is reflected by the second reflector 52a and then reflected by the first reflector 51 and enters the projection lens 60, are mainly light emitted in a direction not parallel to the perpendicular line 41L. However, the light L1a may include light emitted in a direction not parallel to the perpendicular line 41L, and the light L1c may include light emitted in a direction parallel to the perpendicular line 41L.

[0104] Figure 12 shows the light distribution pattern of the low beam in this embodiment. In Figure 12, S represents a horizontal line, V represents a vertical line passing through the center of the vehicle in the left-right direction, and the light distribution pattern PL of the low beam projected onto a virtual vertical screen positioned 25 m in front of the vehicle is shown by a thick line. The reflector unit 50 is shaped such that the light distribution pattern of the light from the first light source 41 incident on the projection lens 60 becomes this low beam light distribution pattern PL. The cutoff line CL of the low beam light distribution pattern PL corresponds to the shape of the front end 51e of the first reflector 51, and in this embodiment, it has a step.

[0105] Next, we will explain how the high beam light distribution pattern is formed by the vehicle headlight 1.

[0106] When forming the high beam light distribution pattern, light is emitted from both the first light source and the second light source 42. As a result, as described above, the light from the first light source 41 forms the low beam light distribution pattern PL, and light having the low beam light distribution pattern PL is emitted from the vehicle headlight 1. A portion of the light L2a emitted from the second light source 42 passes between the lower reflective surface 51dr of the first reflector 51 and the other second reflector 52b and directly enters the projection lens 60. Another portion of the light L2b emitted from the second light source 42 is reflected toward the projection lens 60 at the portion of the lower reflective surface 51dr of the first reflector 51 that includes the front end, and enters the projection lens 60. Yet another portion of the light L2c emitted from the second light source 42 is reflected toward the projection lens 60 at the reflective surface 52br of the other second reflector 52b and enters the projection lens 60. Of the light emitted from the second light source 42, the light passing near the front end 51e of the first reflector 51 forms a cutoff line corresponding to the front end 51e in the light distribution pattern formed by the light emitted from the second light source 42. Although not shown in the illustrations, a portion of the light emitted from the second light source 42 that diffuses in the left-right direction is reflected by the pair of lower side reflectors 54a and 54b and incident on the projection lens 60. In this way, an additional light distribution pattern is formed by the light emitted from the second light source 42 that directly incident on the projection lens 60 and the light emitted from the second light source 42 that is reflected by the reflector unit 50 and incident on the projection lens 60. This additional light distribution pattern is a light distribution pattern that is added to the low beam light distribution pattern PL to form the high beam light distribution pattern, and the light emitted from the second light source 42 that forms the additional light distribution pattern together with the light emitted from the first light source 41 to form the high beam light distribution pattern. In this way, an additional light distribution pattern is formed by the light from the second light source 42, and the light having this additional light distribution pattern passes through the projection lens 60 and is emitted from the vehicle headlight 1 via the front cover 12. Therefore, light having the high beam light distribution pattern is emitted from the vehicle headlight 1. The additional light distribution pattern projected in front of the vehicle is a light distribution pattern that is inverted by the projection lens 60, similar to the low beam light distribution pattern PL.Furthermore, the cutoff line of the additional light distribution pattern is defined by the front end 51e of the first reflector 51, similar to the cutoff line CL of the low beam light distribution pattern PL. As a result, the cutoff line of the additional light distribution pattern and the cutoff line CL of the low beam light distribution pattern PL generally coincide, and the high beam light distribution pattern is a combination of the additional light distribution pattern and the low beam light distribution pattern PL.

[0107] In this embodiment, the upper side of the low beam light distribution pattern PL and the lower side of the additional light distribution pattern overlap, but the low beam light distribution pattern PL and the additional light distribution pattern do not have to overlap. In this case, at least a portion of the cutoff line of the additional light distribution pattern and at least a portion of the cutoff line CL of the low beam light distribution pattern PL coincide, and the additional light distribution pattern and the low beam light distribution pattern PL are connected. Also, in this embodiment, the light L2a that directly incident on the projection lens 60 is mainly light emitted in a direction parallel to the perpendicular line 42L. In addition, the light L2b that is reflected by the first reflector 51 and incident on the projection lens 60, and the light L2c that is reflected by the second reflector 52a and incident on the projection lens 60 are mainly light emitted in a direction not parallel to the perpendicular line 42L. However, the light L2a may include light emitted in a direction not parallel to the perpendicular line 42L, and the light L2b may include light emitted in a direction parallel to the perpendicular line 42L. Furthermore, in this embodiment, the integrated circuit 43 allows for individual adjustment of the power supplied to each LED of the second light source 42, thereby changing the additional light distribution pattern and thus the high beam light distribution pattern.

[0108] Figure 13 shows the light distribution pattern of the high beam in this embodiment, and is similar to Figure 12 in that it shows the light distribution pattern of the high beam. Note that the light distribution pattern PH of the high beam shown in Figure 13 is the case when light is emitted from all LEDs constituting the second light source 42. Also, in Figure 13, the cutoff line CL in the light distribution pattern PL of the low beam is shown by a dotted line. In the light distribution pattern PH of the high beam, the region below the cutoff line CL is mainly formed by light from the first light source, and the region above the cutoff line CL is mainly formed by light from the second light source 42.

[0109] However, as with the lamp described in Patent Document 1 mentioned above, when the reflector unit presses the substrate against the heat sink, there is a concern that the pressing force of the reflector unit will distort the substrate, changing the direction of the light source and forming a light distribution pattern different from the predetermined one.

[0110] Therefore, in the vehicle headlight 1 of this embodiment as the first aspect, the substrate 40 on which the first light source 41 and the second light source 42 are mounted has recesses 45 on each of the opposing sides 40sf. The reflector unit 50 presses on the portion of the substrate 40 that is outside the bottom 45B of each recess 45. As a result, the strength of the portion of the substrate 40 that is outside the bottom 45B of each recess 45 is weakened compared to the case where the substrate 40 does not have recesses 45, and the reflector unit 50 presses on the portion that is thus weakened. Therefore, according to the vehicle headlight 1 of this embodiment as the first aspect, the distortion of the substrate 40 due to the pressing force of the reflector unit 50 can be concentrated on the portion that is weakened, and the distortion inside the bottom 45B of the recess 45 can be reduced compared to the above case. Furthermore, in the vehicle headlight 1 of this embodiment as a first aspect, the first light source 41 and the second light source 42 are located inside the bottom 45B of the recess 45. Therefore, according to the vehicle headlight 1 of this embodiment as a first aspect, compared to the above case, it is possible to suppress changes in the orientation of the first light source 41 and the second light source 42 due to distortion of the substrate 40, and it is possible to make it easier to form the light distribution patterns for low beam and high beam. Also, in the vehicle headlight 1 of this embodiment as a first aspect, the reflector unit 50 presses against one side of the recess 45 and the other side of the recess 45 on the substrate 40. Therefore, according to the vehicle headlight 1 of this embodiment as a first aspect, compared to the case where the reflector unit 50 presses against only one side of the recess on the substrate 40, it is possible to suppress a shift in the relative position between the substrate 40 and the heat sink 20, and it is possible to make it easier to form the light distribution patterns for low beam and high beam.

[0111] Furthermore, in the vehicle headlight 1 of this embodiment as the first aspect, the reflector unit 50 presses both sides of each recess 45 in the substrate 40. Therefore, according to the vehicle headlight 1 of this embodiment as the first aspect, it is possible to suppress the shift in the relative position between the substrate 40 and the heat sink 20 compared to the case where the reflector unit 50 presses only one side of each recess 45 in the substrate 40.

[0112] Furthermore, in the vehicle headlight 1 of this embodiment as a first aspect, the reflector unit 50 has a flat opposing surface 50as that faces the substrate 40, and openings 55 and 56 that penetrate from the opposing surface 50as to the surface opposite to the substrate 40. The first light source 41 overlaps with the opening 55, and the opening 56 overlaps with the second light source 42. For this reason, according to the vehicle headlight 1 of this embodiment as a first aspect, the opposing surface 50as can be formed by machining, for example, compared to the case where the opposing surface 50as is not flat.

[0113] Furthermore, in the vehicle headlight 1 of this embodiment as a first aspect, an integrated circuit 43 that adjusts the power supplied to at least one of the first light source 41 and the second light source 42 and a connector 44 are mounted on the substrate 40, and the integrated circuit 43 and connector 44 are covered by the reflector unit 50. Therefore, according to the vehicle headlight 1 of this embodiment as a first aspect, it is possible to suppress the irradiation of the integrated circuit 43 by sunlight or the like that entering from the outside through the projection lens 60.

[0114] Incidentally, the bright areas in the low beam and high beam light distribution patterns greatly affect visibility. Generally, the area near the cutoff line in the low beam light distribution pattern is bright, and the area near the center in the high beam light distribution pattern is bright. In the vehicle headlight described in Patent Document 1, the light emission surfaces of the first and second light sources are planar, the first and second light sources are mounted on different substrates, and the perpendiculars of the respective emission surfaces of the first and second light sources approach the first reflector towards the front. The luminous flux of light emitted from a light source with a planar emission surface tends to increase as it approaches the perpendicular to the emission surface. For this reason, in the vehicle headlight described in Patent Document 1, the light from the first light source can brighten the front end of the upper surface of the first reflector, and it is thought that the area near the cutoff line in the low beam light distribution pattern can be brightened. Furthermore, it is believed that the light from the second light source can brighten the front end of the lower surface of the first reflector, brighten the low beam light distribution pattern side of the additional light distribution pattern, and brighten the area near the center of the high beam light distribution pattern. However, in the vehicle headlight described in Patent Document 1, the first and second light sources are mounted on different substrates, which tends to increase the number of components.

[0115] Therefore, in the vehicle headlight 1 of this embodiment, which is a second aspect, the first light source 41 and the second light source 42 are mounted on a common substrate 40, which reduces the number of components compared to the case where the first light source 41 and the second light source 42 are mounted on different substrates.

[0116] Furthermore, in the vehicle headlight 1 of this embodiment, which is a second aspect, the perpendicular 41L of the emission surface 41s of the first light source 41 differs from the perpendiculars of the emission surfaces of the first and second light sources in the first patent document, as it is set away from the first reflector 51 in the forward direction. As a result, the luminous flux of light L1b emitted from the first light source 41 and directly incident on the front end of one of the reflective surfaces 51ur of the first reflector 51 tends to be small, making it difficult to brighten the front end. However, along with this light L1b, light L1c emitted from the first light source 41 and reflected by the second reflector 52a also incident on the front end of the reflective surface 51ur of the first reflector 51, and these lights L1b and L1c are reflected toward the projection lens 60. As a result, even with such a first light source 41, it is possible to suppress the darkening of the front end of the reflective surface 51ur, which is the upper surface of the first reflector 51. Furthermore, the perpendicular line 42L of the emission surface 42s of the second light source 42 approaches the first reflector 51 toward the front, similar to the perpendicular lines of the emission surfaces of the first and second light sources in the first patent document. As a result, the light from the second light source 42 can brighten the front end of the reflective surface 51dr, which is the lower surface of the first reflector 51. Therefore, the vehicle headlight 1 of this embodiment, as a second aspect, can suppress the darkening of the front end of the upper and lower surfaces of the first reflector 51. Accordingly, the vehicle headlight 1 of this embodiment can suppress the darkening of the vicinity of the cutoff line CL in the low beam light distribution pattern PL and the vicinity of the center of the high beam light distribution pattern PH, thereby suppressing a decrease in visibility.

[0117] In the vehicle headlight 1 of this embodiment as a second aspect, some of the other light L1c emitted from the first light source 41 is reflected back to the first reflector 51 with a divergence angle smaller than that at one of the second reflectors 52a than at the incident light source. Therefore, according to the vehicle headlight 1 of this embodiment as a second aspect, the darkening of the vicinity of the cutoff line CL in the low beam light distribution pattern PL can be further suppressed. In this embodiment, the reflective surface 52ar that reflects the light L1c in the second reflector 52a is part of a spheroid, with one focal point on the spheroid located at the front end of the reflective surface 51ur of the first reflector 51 and the other focal point located at the intersection of the emission surface 41s of the first light source 41 and the perpendicular line 41L. However, the shape of the reflective surface 52ar is not particularly limited. Some of the other light L1c may be reflected back to the first reflector 51 with a divergence angle the same as or larger than that at one of the second reflectors 52a than at the incident light source.

[0118] Furthermore, in the vehicle headlight 1 of this embodiment as a second aspect, some of the other light L2c emitted from the second light source 42 is reflected toward the projection lens 60 at the other second reflector 52b with a divergence angle larger than that at the incident light. For this reason, the vehicle headlight 1 of this embodiment as a second aspect makes it easier to widen the high beam light distribution pattern PH upward. Note that some of the other light L2c may be reflected toward the projection lens 60 at the other second reflector 52b with a divergence angle the same as or smaller than that at the incident light.

[0119] Furthermore, the vehicle headlight 1 of this embodiment, as a second embodiment, further includes an integrated circuit 43 mounted on a substrate 40 that adjusts the power supplied to at least one of the first light source 41 and the second light source 42. The reflector unit 50 also has a cover portion 50b that covers the integrated circuit 43. Therefore, according to the vehicle headlight 1 of this embodiment, it is possible to suppress the irradiation of the integrated circuit 43 by sunlight or the like that entering from the outside through the projection lens 60.

[0120] Although the first aspect of the present invention has been described using the first embodiment as an example, the first aspect of the present invention is not limited thereto.

[0121] For example, in the first embodiment, a heat sink 20 having protrusions 26 that are inserted into each recess 45 was described as an example. However, in the first embodiment, the heat sink 20 does not have to have protrusions 26.

[0122] Furthermore, in the first embodiment, a reflector unit 50 that presses both sides of each recess 45 in the substrate 40 was described as an example. However, in the first embodiment, the reflector unit 50 only needs to press the portion of each recess 45 in the substrate 40 that is outside the bottom portion 45B, which is the tip in the recess direction. The reflector unit 50 may press one side of each recess 45 in the substrate 40, for example, it may press only portions 46a and 46c shown in Figure 6, or only portions 46b and 46d. In addition, the reflector unit 50 may further press the portion of the substrate 40 that is inside each recess 45.

[0123] Furthermore, in the first embodiment, a substrate 40 having one recess 45 on each side was described as an example. However, in the first embodiment, the substrate 40 only needs to have recesses 45 on each of its opposing sides. For example, the substrate 40 may have multiple recesses 45 on one side and the other side, and the number of recesses 45 on one side may be different from the number of recesses 45 on the other side. Also, in the first embodiment, a substrate 40 on which a first light source 41 and a second light source, which are LED arrays, are mounted was described as an example. However, in the first embodiment, the light sources mounted on the substrate 40 are not particularly limited.

[0124] Furthermore, in the first embodiment, a reflector unit 50 that covers a connector 44 mounted on a substrate 40 was described as an example. However, in the first embodiment, the reflector unit 50 does not have to cover the connector 44, as shown in Figure 14.

[0125] Figure 14 shows the reflector unit 50 attached to the heat sink 20 in the first modified example as a first embodiment, similar to Figure 7, and Figure 15 shows the luminaire unit LU in the first modified example, similar to Figure 4. Note that redundant descriptions of components identical or equivalent to those in the above embodiments are omitted unless specifically described with the same reference numerals.

[0126] As shown in Figures 14 and 15, in this modified example, the shape of the cover portion 50b of the reflector unit 50 differs from the shape of the cover portion 50b in the first embodiment. In this modified example, the cover portion 50b of the reflector unit 50 is not formed on the lower side of the connector 44, which is opposite to the first light source 41 and the second light source 42, in the direction along the front surface 40f of the substrate 40. Therefore, compared to the case where the reflector unit 50 is formed on the side of the connector 44 that is opposite to the first light source 41 and the second light source 42, it is possible to connect other connectors to the connector 44 more easily. Also, when the substrate 40 is viewed from above, the cover portion 50b does not cover the connector 44, which makes it easier to connect other connectors to the connector 44. Furthermore, in this modified example, the flat opposing surface 50as of the light distribution forming portion 50a, which is generally parallel to the front surface 40f of the substrate 40, extends to the outer edge of the surface of the reflector unit 50 that is on the substrate 40 side. Therefore, for example, the opposing surface 50as can be easily formed by machining.

[0127] Furthermore, in the first embodiment and the first modification, a vehicle headlight 1 was used as an example of a lighting device. However, the lighting device in the first embodiment only needs to include a substrate on which a light source is mounted, a heat sink on which the substrate is placed, and a reflector that presses the substrate against the heat sink and reflects a portion of the light emitted from the light source. For example, the lighting device in the first embodiment does not have to be for a vehicle, and may emit light that constitutes a predetermined image.

[0128] Furthermore, although the second aspect of the present invention has been described using the first embodiment as an example, the second aspect of the present invention is not limited thereto.

[0129] For example, in the first embodiment, a first light source 41 whose perpendicular line 41L moves away from the first reflector 51 in the forward direction, and a second light source whose perpendicular line 42L moves towards the first reflector 51 in the forward direction were described as an example. However, in the second embodiment, it is sufficient for the perpendicular line of one of the light sources, the first light source 41 and the second light source 42, to move away from the first reflector 51 in the forward direction, and the perpendicular line of the other light source to move towards the first reflector 51 in the forward direction. For example, as shown in Figure 16, the perpendicular line 41L of the first light source 41 may move towards the first reflector 51 in the forward direction, and the perpendicular line 42L of the second light source 42 may move away from the first reflector 51 in the forward direction. Also, in the first embodiment, the first light source 41 and the second light source were described as LED arrays as an example. However, in the second embodiment, the first light source 41 and the second light source are not particularly limited as long as their emission surfaces are flat.

[0130] Figure 16 is a diagram showing, similar to Figure 11, an example of the optical paths of light emitted from the first light source 41 and light emitted from the second light source 42 in a second modified example as a second embodiment. Note that the reflection angle and refraction angle of light shown in Figure 16 may not be accurate. Also, for components that are the same as or equivalent to those in the first embodiment, redundant explanations are omitted unless they are specifically described with the same reference numerals.

[0131] As shown in Figure 16, in the luminaire unit LU of this modified example, the substrate 40 is tilted forward toward upward, and the light distribution forming portion 50a of the reflector unit 50 is shaped like the light distribution forming portion 50a in the above embodiment is inverted vertically.

[0132] In this modified example, some of the light L1a emitted from the first light source 41 passes between the upper reflective surface 51ur of the first reflector 51 and one of the second reflectors 52a and is directly incident on the projection lens 60. Another portion of the light L1b is reflected toward the projection lens 60 at the portion of the upper reflective surface 51ur of the first reflector 51 that includes the front end, and is incident on the projection lens 60. Yet another portion of the light L1c is reflected toward the projection lens 60 at the reflective surface 52ar of the second reflector 52a, and is incident on the projection lens 60. Although not shown in the illustrations, similar to the above embodiment, some of the light emitted from the second light source 42 that diffuses in the left-right direction is reflected by the pair of lower side reflectors 54a, 54b and is incident on the projection lens 60. In this way, the light emitted from the first light source 41 and directly incident on the projection lens 60, and the light emitted from the first light source 41, reflected by the reflector unit 50 and incident on the projection lens 60, form the low beam light distribution pattern PL shown in Figure 12.

[0133] In this modified example, the perpendicular line 41L of the first light source 41 approaches the first reflector 51 toward the front, so that the light from the first light source 41 can brighten the front end of the reflective surface 51ur, which is the upper surface of the first reflector 51. For this reason, according to the vehicle headlight 1 of this modified example as a second embodiment, it is possible to suppress the darkening of the vicinity of the cutoff line CL in the low beam light distribution pattern PL, and thus suppress the decrease in visibility.

[0134] Furthermore, some of the light L2a emitted from the second light source 42 passes between the lower reflective surface 51dr of the first reflector 51 and the second reflector 52b and is directly incident on the projection lens 60. Another portion of the light L2b is reflected toward the projection lens 60 at the portion of the lower reflective surface 51dr of the first reflector 51, including the front end, and is incident on the projection lens 60. Yet another portion of the light L2c is reflected by the reflective surface 52br of the second reflector 52b and is reflected toward the projection lens 60 at the portion of the reflective surface 51dr of the first reflector 51, including the front end. Although not shown in the illustrations, similar to the first embodiment, some of the light emitted from the second light source 42 that diffuses in the left-right direction is reflected by the pair of lower side reflectors 54a and 54b and is incident on the projection lens 60. In this way, an additional light distribution pattern is formed by the light emitted from the second light source 42 and directly incident on the projection lens 60, and the light emitted from the second light source 42, reflected by the reflector unit 50, and incident on the projection lens 60. This additional light distribution pattern is a light distribution pattern that is added to the low beam light distribution pattern PH to form the high beam light distribution pattern, and the high beam light distribution pattern PH shown in Figure 13 is formed by the light from the first light source 41 and the second light source 42.

[0135] In this modified example, the luminous flux of light L2b emitted from the second light source 42 and directly incident on the front end of the reflective surface 51dr of the first reflector 51 tends to be small, making it difficult to brighten the front end. However, along with this light L2b, light L2c emitted from the second light source 42 and reflected by the second reflector 52b also incident on the front end of the reflective surface 51dr of the first reflector 51, and these lights L1b and L1c are reflected toward the projection lens 60. Therefore, even with such a second light source 42, it is possible to suppress the darkening of the front end of the reflective surface 51dr, which is the lower surface of the first reflector 51. For this reason, according to the vehicle headlight 1 of this modified example as a second embodiment, it is possible to suppress the darkening of the area near the center of the high beam light distribution pattern PH, and thus suppress the decrease in visibility.

[0136] Thus, the vehicle headlight 1 of this modified example, as a second embodiment, can reduce the number of parts while suppressing a decrease in visibility, similar to the first embodiment.

[0137] Furthermore, in this modified example, some of the other light L1c emitted from the first light source 41 is reflected towards the projection lens 60 at the second reflector 52a with a divergence angle larger than that at the incident light source. Therefore, according to the vehicle headlight 1 of this modified example as a second embodiment, the low beam light distribution pattern PL can be easily spread downwards. In addition, some of the other light L1c may be reflected towards the projection lens 60 at the second reflector 52a with a divergence angle the same as or smaller than that at the incident light source.

[0138] Furthermore, in this modified example, some of the other light L2c emitted from the second light source 42 is reflected toward the first reflector 51 with a divergence angle smaller than that at the second reflector 52b than at the incident light source. Therefore, according to the vehicle headlight 1 of this modified example as a second embodiment, the darkening of the area near the center of the high beam light distribution pattern PH can be further suppressed. In this modified example, the reflective surface 52br that reflects the light L2c in the second reflector 52b is part of a spheroid, with one focal point of the spheroid located at the front end of the reflective surface 51dr of the first reflector 51 and the other focal point located at the center of the emission surface 42s of the second light source 42. However, in the second embodiment, the shape of the reflective surface 52br is not particularly limited. Some of the other light L2c may be reflected toward the first reflector 51 with a divergence angle the same as or larger than that at the second reflector 52b than at the incident light source.

[0139] Furthermore, in the first embodiment and the second modification, a reflector unit 50 having a cover portion 50b that covers the integrated circuit 43 and the connector 44 was described as an example. However, in the second embodiment, the cover portion 50b does not have to cover at least one of the integrated circuit 43 and the connector 44, and the reflector unit 50 does not have to have a cover portion 50b.

[0140] Furthermore, in the first embodiment and the second modified example, a substrate 40 having a recess 45 into which the projection 26 of the heat sink 20 is inserted was described as an example. However, in the second embodiment, the substrate 40 does not have to have a recess 45.

[0141] Furthermore, in the first embodiment and the second modification, a reflector unit 50 that presses the substrate 40 against the heat sink 20 was described as an example. However, in the second embodiment, the reflector unit 50 does not need to press the substrate 40 against the heat sink 20. In this case, for example, the substrate 40 is fixed to the heat sink 20 by screws.

[0142] (Second Embodiment) Next, a second embodiment, which is a third aspect of the present invention, will be described. Note that components identical or equivalent to those in the first embodiment are denoted by the same reference numerals unless otherwise specified, and redundant descriptions will be omitted.

[0143] Figure 17 is a schematic diagram of the vehicle headlight in this embodiment. As shown in Figure 17, the configuration of the luminaire unit LU in the vehicle headlight 1 of this embodiment differs from the configuration of the luminaire unit LU in the first embodiment.

[0144] Figure 18 is an exploded perspective view of the luminaire unit LU shown in Figure 17. As shown in Figure 18, the luminaire unit LU comprises a projection lens 110, a lens holder 120, a reflector unit 130, a substrate 140, a heat sink 150, and a cooling fan 160.

[0145] The projection lens 110 of this embodiment has a lens body 111 and a flange-shaped fixing portion 112 provided on the outer circumference of the lens body 111. The lens body 111 has a convex light emission surface 113 and an incident surface 114 which is convex with a smaller curvature than the emission surface 113. In addition, the lens body 111 has a shape in which the upper and lower portions of a circular lens are cut off in a planar manner when viewed from the front, resulting in a thin shape in the vertical direction. The focal plane of the projection lens 110 is roughly aligned with the light emission surface of the light-emitting element described later.

[0146] The lens holder 120 has a roughly rectangular, cylindrical shape that matches the outer shape of the lens body 111, and has a bottom plate 121, side plate portions 122 connected to both left and right edges of the bottom plate portion 121, and a top plate portion 123 facing the bottom plate portion 121 and connected to each of the side plate portions 122. The bottom plate portion 121 and the top plate portion 123 extend roughly horizontally, and the side plate portions 122 extend roughly vertically. The fixing portion 112 of the projection lens 110 is fixed to the edge of the lens holder 120, so that the lens holder 120 holds the projection lens 110, and the incident surface 114 of the projection lens 110 is exposed in the through hole of the lens holder 120. In addition, fixing portions 125 that are fixed to the heat sink 150 are provided on the outside of each side plate portion 122. Furthermore, a recess 121c is formed on the edge of the bottom plate portion 121 opposite to the projection lens 110 side.

[0147] Figure 19 shows the reflector unit 130 in this embodiment. The reflector unit 130 is made of metal and, as shown in Figures 18 and 19, mainly consists of a reflective part 131, a light-shielding cover 132, a fixing part 134, and a blind plate 135. The reflector unit 130 also has an opening 130h formed in the rear from which the emission surface of the light-emitting element described later is exposed. In this example, the opening 130h is a horizontally elongated, generally rectangular shape. The reflective part 131 is a generally trapezoidal portion that extends from directly below the opening 130h to the front and downward, and the upper base of the reflective part 131 is the lower edge of the opening 130h. The length of this upper base and the width of the opening 130h in the left-right direction are generally equal. The reflective part 131 reflects the light emitted from the light source exposed from the opening 130h to the front and downward toward the projection lens 110.

[0148] A light-shielding cover 132 is provided below the reflective portion 131. The light-shielding cover 132 has a light-scattering portion 132d, a plate-shaped cover portion 132p, and a side cover portion 132s, and protects the member of the light-shielding cover 132 located on the side opposite to the projection lens 110 from sunlight incident from the projection lens 110.

[0149] A light-scattering section 132d extends vertically downward from the lower end of the reflective section 131. The surface of the light-scattering section 132d has a shape in which multiple semi-cylinders extending in the vertical direction are arranged in parallel in the horizontal direction. As a result, the light reflected by the light-scattering section 132d is scattered. The width of the light-scattering section 132d in the horizontal direction is narrower than the width of the lower base of the trapezoidal reflective section 131 and is approximately the same as the width of the upper base of the reflective section 131.

[0150] A plate-shaped cover portion 132p is connected to the lower edge of the light-scattering portion 132d. The plate-shaped cover portion 132p extends horizontally forward from the light-scattering portion 132d. The upper surface of the plate-shaped cover portion 132p has a shape in which multiple semi-cylinders extending in the front-to-back direction are arranged in parallel in the left-to-right direction. Therefore, light reflected from the upper surface of the plate-shaped cover portion 132p is scattered. The left-to-right width of the plate-shaped cover portion 132p is smaller than the left-to-right width of the bottom plate portion 121 of the lens holder 120, and slightly smaller than the width of the recess 121c. This width is also larger than the left-to-right width of the light-scattering portion 132d, and each left-to-right end portion 132pe of the plate-shaped cover portion 132p extends behind the light-scattering portion 132d. A side cover portion 132s is connected to the rear end of each end portion 132pe. Each side cover portion 132s is a plate-like member that extends in a convex arc toward the rear and upward from the connection point with the end portion 132pe. Furthermore, the upper surface of each side cover portion 132s is generally flat and does not have any particular light scattering properties.

[0151] Each side cover portion 132s has a vertically extending, flat fixing portion 134 connected to its rear end. Each fixing portion 134 is connected to the left and right edges of the opening 130h. Each fixing portion 134 also has a screw hole 134h formed in it. The upper edge of the opening 130h is connected to a roughly rectangular, flat cover plate 135. The left and right edges of the cover plate 135 are each connected to a fixing portion 134.

[0152] As shown in Figure 18, the circuit board 140 has components mounted on one side and arranged vertically. The circuit board 140 is roughly rectangular in shape, and screw holes 140h are formed near the upper left and right corners. Each screw hole 140h is formed in a position that overlaps with the screw holes 134h of the reflector unit 130. Therefore, a common screw is inserted through the screw holes 134h and 140h. Multiple terminals 145 are provided on the underside of the circuit board 140, to which connectors are connected. Cables are connected to these connectors. These connectors and cables are conductive members that supply power to the components mounted on the circuit board 140.

[0153] A light source 141 is mounted on one side of the substrate 140. The light source 141 includes a plurality of light-emitting elements 141e arranged in parallel to each other and emitting light forward. LEDs are examples of such light-emitting elements. In this embodiment, the plurality of light-emitting elements 141e are mounted in a single row in the left-right direction on the upper side of the substrate 140. The light-emitting surfaces of the plurality of light-emitting elements 141e, which are the light-emitting surfaces of the light source 141, are exposed through the opening 130h of the reflector unit 130 when the reflector unit 130 and the substrate 140 are placed on the heat sink 150. The light source 141 is sandwiched from the left and right by a pair of screw holes 140h. In addition to the light source 141, other electronic components are also mounted on the substrate 140.

[0154] The heat sink 150 comprises a base plate 151 on which the substrate 140 is placed, and a plurality of cooling fins 152 arranged in parallel on the side of the base plate 151 opposite to the substrate 140 side. The base plate 151 has screw holes 150h formed at positions corresponding to the screw holes 134h of the reflector unit 130 and the screw holes 140h of the substrate 140. Therefore, screws that are fixed to the screw holes 150h are inserted through the screw holes 134h and 140h. When the substrate 140 is placed on the heat sink 150, it is preferable that thermal conductive grease is interposed between the base plate 151 and the substrate 140.

[0155] Figure 20 shows the projection lens 110 removed from the luminaire unit LU in this embodiment. As shown in Figure 20, the reflector unit 130 is fixed to the heat sink 150 together with the substrate 140 by screws inserted into screw holes 134h and 140h and fixed in screw hole 150h. The lens holder 120 is also fixed to the heat sink 150 by the fixing portion 125 of the lens holder 120 being screwed to the heat sink 150. In this state, a part of the plate-shaped cover portion 132p of the reflector unit 130 fits into a recess 121c formed in the bottom plate portion 121 of the lens holder 120. This fitting of a part of the plate-shaped cover portion 132p into the recess 121c helps to suppress lateral misalignment between the reflector unit 130 and the lens holder 120.

[0156] Figure 21 is a vertical cross-sectional view of the luminaire unit LU in this embodiment. Note that since Figure 21 is a cross-sectional view passing through the cooling fins 152, the cooling fins 152 are not shown in Figure 21. With the lens holder 120 fixed to the heat sink 150, as shown in Figure 21, a part of the side surface 132ps of the plate-shaped cover portion 132p and the side surface of the bottom plate portion 121 face each other. Therefore, a part of the plate-shaped cover portion 132p and the side surface 132ps overlap with the bottom plate portion 121 in the direction of extension of the bottom plate portion 121. It is more preferable that the entire side surface 132ps of the plate-shaped cover portion 132p and the bottom plate portion 121 overlap in the direction of extension of the bottom plate portion 121.

[0157] A cooling fan 160, including a rotating blade 165, is positioned on multiple cooling fins 152 of the heatsink 150. As mentioned above, the cooling fins 152 are not shown in Figure 21, so in Figure 21, the heatsink 150 and the cooling fan 160 appear to be separate. Figure 22 shows the lighting unit LU with the projection lens 110, lens holder 120, and reflector unit 130 removed. As shown in Figure 22, the cooling fan 160 has a cable 161 and a connector 162 that supply power to the cooling fan 160. Note that the cable 161 and connector 162 are omitted in Figures 18, 20, and 21. The cable 161 has a configuration in which the conductor is covered with insulating resin, and the connector 162 has a configuration in which the terminals of the conductor are covered with a resin case. The power supplied from the cable 161 and connector 162 rotates the rotating blade 165, blowing air between the cooling fins 152. Therefore, the cable 161 and connector 162 are conductive members that supply power to drive the cooling fan 160.

[0158] As can be seen from comparing Figure 20 and Figure 22, in this embodiment, the cable 161 and connector 162 are positioned below the reflector portion 131, and the connector 162 is hidden below the plate-shaped cover portion 132p and the side cover portion 132s of the reflector unit 130.

[0159] Figure 22 also shows a cable unit 170 connected to the substrate 140. The cable unit 170 comprises a cable 171 and a connector 172. The connector 172 has a resin case that covers multiple terminals (not shown). With the connector 172 connected to the substrate 140 as shown in Figure 22, the multiple terminals of the connector 172 are each connected to terminal 145. The configuration of the cable 171 is the same as that of the cable 161, and the conductors of the cable 171 are connected to each terminal of the connector 172. The power supplied from the cable 171 and the connector 172 causes each light-emitting element 141e of the light source 141 to emit light. Therefore, the cable 171 and the connector 172 are conductive members that supply power to emit light from the light source 141. In this embodiment, the cable 171 and the connector 172 are located below the reflector 131, and the cable 171 and the connector 172 are hidden below the plate-shaped cover portion 132p of the reflector unit 130.

[0160] In other words, the light-shielding cover 132 of the reflector unit 130 is located between the projection lens 110 and the conductive member, protecting the conductive member that supplies power to drive the cooling fan 160 and the conductive member that supplies power to emit light from the light source 141 from sunlight entering through the projection lens 110.

[0161] In the vehicle headlight 1 configured as described above, power is supplied from terminals 145 provided on the circuit board 140. This power activates the circuits on the circuit board 140, supplying power to each light-emitting element 141e, causing each light-emitting element 141e to emit light. Thus, light is emitted from the light source 141, and this light is emitted from the aperture 130h of the reflector unit 130. Of the light emitted from the light source 141, the light along the optical axis is directly incident on the projection lens 110. On the other hand, the light emitted from the light source 141 to the front and lower is reflected forward by the reflector part 131 of the reflector unit 130 and incident on the projection lens 110. The light emitted from the light source 141 and incident on the projection lens 110 passes through the projection lens 110 and is irradiated in a predetermined light distribution pattern.

[0162] Incidentally, while the aforementioned Patent Document 2 discusses suppressing damage to the lens holder, it does not consider damage to conductive components such as cables and connectors that supply power to the light source and cooling fan. Such conductive components generally contain resin covering the wires, and are therefore susceptible to damage when exposed to concentrated sunlight. Furthermore, there is a demand to reduce costs in order to suppress this damage.

[0163] Therefore, the vehicle headlight 1 of this embodiment comprises a light source 141, a reflector unit 130 having a reflector portion 131 that reflects light emitted from the light source 141 forward and downward, a projection lens 110 through which the light reflected by the reflector portion 131 is transmitted, and conductive members such as a cable 161 and a connector 162 arranged below the reflector portion 131.

[0164] The reflector unit 130 is integrally formed with the reflective portion 131 and has a light-shielding cover 132 located between the projection lens 110 and the conductive member below the reflective portion 131. This suppresses the irradiation of the conductive member by sunlight incident through the projection lens 110. Furthermore, the reflective portion 131 normally has light-shielding properties. Therefore, by integrating the light-shielding cover 132 and the reflective portion 131, both of which have light-shielding properties, it is possible to suppress damage to the conductive member by sunlight at low cost.

[0165] Furthermore, in the vehicle headlight 1 of this embodiment, at least a portion of the side surface 132ps of the plate-shaped cover portion 132p of the reflector unit 130 overlaps with the bottom plate portion 121 of the lens holder 120 in the extending direction. If the plate-shaped cover portion 132p does not overlap with the bottom plate portion 121 in the extending direction and the plate-shaped cover portion 132p is located below the bottom plate portion 121, sunlight propagating toward the plate-shaped cover portion 132p may damage the lens holder 120. If the plate-shaped cover portion 132p is located above the bottom plate portion 121, sunlight propagating toward the plate-shaped cover portion 132p is reflected by the entire side surface 132ps of the plate-shaped cover portion 132p, and the reflected light may damage the lens holder 120. Therefore, as described above, by overlapping the plate-shaped cover portion 132p with the bottom plate portion 121 in the extending direction, damage to the lens holder 120 by sunlight propagating toward the plate-shaped cover portion 132p can be suppressed. However, if sunlight propagating toward the plate-shaped cover portion 132p is to be reflected by the side surface 132ps of the plate-shaped cover portion 132p, then the plate-shaped cover portion 132p does not need to overlap the bottom plate portion 121 in the extending direction.

[0166] Furthermore, in the vehicle headlight 1 of this embodiment, the upper surface of the plate-shaped cover portion 132p scatters and reflects incident light, so that sunlight propagating to the plate-shaped cover portion 132p is scattered, and damage to other components by reflected sunlight can be suppressed. However, the upper surface of the plate-shaped cover portion 132p does not necessarily have to scatter and reflect incident light.

[0167] Furthermore, in the vehicle headlight 1 of this embodiment, there is a light scattering portion 132d between the reflecting portion 131 and the plate-shaped cover portion 132p. Therefore, even when the plate-shaped cover portion 132p and the reflecting portion 131 are separated, sunlight propagating between the plate-shaped cover portion 132p and the reflecting portion 131 is scattered, and damage to other components by reflected sunlight can be suppressed. Note that the space between the reflecting portion 131 and the plate-shaped cover portion 132p may be made of a material that does not scatter light.

[0168] Furthermore, in the vehicle headlight 1 of this embodiment, the width of the plate-shaped cover portion 132p in the left-right direction is greater than the width of the light-scattering portion 132d in the left-right direction, and each of the left and right ends 132pe of the plate-shaped cover portion 132p extends further rearward than the light-scattering portion 132d. Therefore, the range of conductive members that can be protected by the plate-shaped cover portion 132p can be widened. In addition, since the light-shielding cover 132 has side cover portions 132s that extend rearward and upward from the rear end of each end 132pe, the range of conductive members that can be protected by the light-shielding cover 132 can be widened even further. Note that such side cover portions 132s are not an essential configuration.

[0169] Although the third aspect of the present invention has been described using the second embodiment as an example, the third aspect of the present invention is not limited thereto.

[0170] For example, in the second embodiment, the light source 141 was described as being composed of multiple light-emitting elements 141e, but the light source 141 may consist of a single light-emitting element.

[0171] (Third embodiment) Next, a third embodiment, which is a fourth aspect of the present invention, will be described. Note that components identical or equivalent to those in the second embodiment are denoted by the same reference numerals unless otherwise specified, and redundant descriptions will be omitted.

[0172] Figure 23 is a schematic diagram of the vehicle headlight in this embodiment. Figure 24 is an exploded perspective view of the lamp unit LU. As shown in Figures 23 and 24, in the vehicle headlight 1 of this embodiment, the configuration of the circuit board 140, heat sink 150, and cooling fan 160 of the lamp unit LU differs from the configuration of the circuit board 140, heat sink 150, and cooling fan 160 of the lamp unit LU in the second embodiment.

[0173] Figure 25 is a front view of the substrate 140 in this embodiment. As shown in Figures 24 and 25, the substrate 140 includes a main body 140m on which components are mounted on one side, and a tail portion 140t, which are arranged vertically. The main body 140m is roughly square in shape, and screw holes 140h are formed near the upper left and right corners. Each screw hole 140h is formed in a position that overlaps with the screw holes 134h of the reflector unit 130. Therefore, the substrate 140 is fixed to the heat sink 150 together with the reflector unit 130 by screws inserted into the screw holes 134h and 140h, as described above. The tail portion 140t is connected to the lower side of the main body 140m, and its width in the left-right direction is smaller than that of the main body 140m, and it is divided into left and right by slits 140ts. The tail portion 140t is provided with a plurality of terminals 145, and the tail portion 140t functions as a card edge connector. Therefore, a connector (not shown) is connected to the tail section 140t, and a cable is connected to this connector. These connectors and cables are conductive members that supply power to components mounted on the circuit board 140.

[0174] A light source 141 and an integrated circuit 142 are mounted on one side of the main body 140m. The light source 141 includes a plurality of light-emitting elements 141e arranged in parallel with each other and emitting light forward. LEDs are examples of such light-emitting elements. In this embodiment, the plurality of light-emitting elements 141e are mounted in a single parallel line in the left-right direction in a light source mounting area 141a provided on the upper side of the main body 140m. The light-emitting surfaces of the plurality of light-emitting elements 141e, which are the light-emitting surfaces of the light source 141, are exposed through the opening 130h of the reflector unit 130 when the reflector unit 130 and the substrate 140 are placed on the heat sink 150. The light source mounting area 141a is sandwiched from the left and right by screw holes 140h. The integrated circuit 142 is electrically connected to each light-emitting element 141e by wiring (not shown) on the substrate and performs switching of power supply to the light source 141. The integrated circuit 142 is mounted in an integrated circuit mounting area 142a located approximately in the center of one of the surfaces of the main body 140m. Other electronic components are mounted on the substrate 140. In addition to the two upper screw holes, the substrate 140 has another screw hole 140uh formed on the underside of the integrated circuit.

[0175] Figure 26 is a front view of the heat sink 150 in this embodiment. As shown in Figures 24 and 26, the heat sink 150 comprises a base plate 151 on which the substrate 140 is placed, and a plurality of cooling fins 152 arranged in parallel on the side of the base plate 151 opposite to the substrate 140 side.

[0176] The base plate 151 includes a substrate-facing region 153, indicated by a dashed line, on the surface facing the substrate 140. The substrate-facing region 153 includes a placement portion 154 that faces the substrate 140 and on which the substrate 140 is placed, and a separation portion 155 that separates from the substrate 140 in the thickness direction of the substrate 140 when the substrate 140 is placed in the placement portion 154. Figure 27 is a vertical cross-sectional view of the luminaire unit LU in this embodiment. As shown in Figure 27, the placement portion 154 is formed convexly toward the substrate 140 than the separation portion 155. Therefore, when the substrate 140 is placed in the placement portion 154, the separation portion 155 separates from the substrate 140 as described above.

[0177] As shown in Figure 26, the arrangement section 154 includes a light source facing region 154e, an integrated circuit facing region 154i, a first connection region 154c1, an adjustment region 154a, and a second connection region 154c2, all of the same height.

[0178] The light source facing region 154e faces the back surface of the light source mounting region 141a on the substrate 140, where the light source 141 is mounted. Therefore, the light source facing region 154e faces the light source 141 via the substrate 140. As described above, the light source 141 includes a plurality of light-emitting elements 141e arranged in parallel in the left-right direction. For this reason, the light source facing region 154e extends along the left-right direction, which is the parallel direction of the plurality of light-emitting elements 141e.

[0179] Screw holes 150h are formed on both sides of the light source facing region 154e in the placement section 154. These screw holes 150h are formed at positions corresponding to the screw holes 140h of the substrate 140. Screws inserted into the screw holes 134h of the reflector unit 130 and the screw holes 140h of the substrate 140 are fixed to the screw holes 150h, and the reflector unit 130 and the substrate 140 are fixed to the heat sink 150 by the fixing of these screws. At this time, the reflector unit 130 presses the area around the screw holes 140h of the substrate 140 against the placement section 154. In this way, both sides of the light source mounting region 141a of the substrate 140 are pressed against the same surface as the light source mounting region 141a, which prevents the back surface of the light source mounting region 141a from lifting away from the heat sink 150. The distance from one end to the other of the pair of screw holes 150h in the arrangement section 154 is approximately the same as the width of the main body 140m of the substrate 140 in the left-right direction.

[0180] The integrated circuit facing region 154i faces the back surface of the integrated circuit mounting region 142a on the substrate 140, where the integrated circuit 142 is mounted. Therefore, the integrated circuit facing region 154i faces the integrated circuit 142 via the substrate 140. The width of the integrated circuit facing region 154i in the left-right direction is smaller than the width of the main body portion 140m of the substrate 140 in the left-right direction, and in this embodiment, it is slightly smaller than the width of the integrated circuit mounting region 142a in the left-right direction. Therefore, in this embodiment, the integrated circuit facing region 154i faces a part of the back surface of the integrated circuit mounting region 142a. However, the width of the integrated circuit facing region 154i in the left-right direction may be greater than or equal to the width of the integrated circuit mounting region 142a in the left-right direction, and the integrated circuit facing region 154i may face the entire back surface of the integrated circuit mounting region 142a.

[0181] The adjustment region 154a is located on the heat sink 150 opposite the lower side of the main body portion 140m of the substrate 140. The adjustment region 154a extends in the left-right direction, and its width in the left-right direction is smaller than the left-right width of the main body portion 140m of the substrate 140, but larger than the left-right width of the integrated circuit facing region 154i. The adjustment region 154a has the function of adjusting the height of the surface on the heat sink 150 on which the substrate 140 is placed, so that the lower part of the substrate 140 does not become unstable when the substrate 140 is placed. In addition, a screw hole 150uh is formed in the adjustment region 154a. The screw hole 150uh is located at a position corresponding to the screw hole 140uh of the substrate 140. Therefore, when a screw inserted through the screw hole 140uh is fixed in the screw hole 150uh, the substrate 140 is pressed against and fixed in the adjustment region 154a. In this way, by forming the screw holes 150uh in the adjustment region 154a, which is wider than the integrated circuit facing region, the substrate 140 is stably fixed to the heat sink 150.

[0182] The first connecting region 154c1 is the region that connects the light source opposing region 154e and the integrated circuit opposing region 154i. The first connecting region 154c1 extends in the vertical direction. Therefore, the first connecting region 154c1 extends in a direction perpendicular to the direction of extension of the light source opposing region 154e, connecting the light source opposing region 154e and the integrated circuit opposing region 154i by the shortest distance. The second connecting region 154c2 is the region that connects the adjustment region 154a and the integrated circuit opposing region 154i. Similarly to the first connecting region 154c1, the second connecting region 154c2 connects the adjustment region 154a and the integrated circuit opposing region 154i by the shortest distance. For this reason, the first connecting region 154c1, the integrated circuit opposing region 154i, and the second connecting region 154c2 are aligned linearly with each other along a direction perpendicular to the direction of extension of the integrated circuit opposing region 154i. Furthermore, in this embodiment, the first connecting region 154c1, the integrated circuit facing region 154i, and the second connecting region 154c2 have the same width along the extending direction of the integrated circuit facing region 154i.

[0183] Separation portions 155 are located on both the left and right sides of the first connecting region 154c1, the integrated circuit facing region 154i, and the second connecting region 154c2. In other words, at least the separation portions 155 are provided in areas other than the region consisting of the light source facing region 154e, the integrated circuit facing region 154i, and the first connecting region 154c1 that connects them by the shortest distance. In this embodiment, in addition to the above, the separation portions 155 are provided in areas other than the region consisting of the adjustment region 154a, the integrated circuit facing region 154i, and the second connecting region 154c2 that connects them by the shortest distance.

[0184] Furthermore, when the substrate 140 is placed on the heat sink 150, it is preferable that thermal conductive grease is interposed between the placement portion 154 and the substrate 140.

[0185] As shown in Figure 24, a cooling fan 160 is positioned on a plurality of cooling fins 152 of the heatsink 150. The cooling fan 160 has a cable 161 and a connector 162, which are conductive members that supply power to the cooling fan 160. The cable 161 has a configuration in which a conductor is covered with insulating resin, and the connector 162 has a configuration in which the terminals of the conductor are covered with a resin case. The power supplied from these conductive members rotates the rotor blades 165, blowing air between the cooling fins 152.

[0186] In the vehicle headlight 1 configured as described above, power is supplied from terminals provided on the tail section 140t, which functions as a card edge connector for the circuit board 140. This power causes the integrated circuit 142 to switch, and this switching supplies power to each light-emitting element 141e, causing each light-emitting element 141e to emit light. Thus, light is emitted from the light source 141, and this light is emitted from the aperture 130h of the reflector unit 130. Of the light emitted from the light source 141, the light along the optical axis is directly incident on the projection lens 110. On the other hand, the light emitted from the light source 141 to the front and lower is reflected forward by the reflector section 131 of the reflector unit 130 and incident on the projection lens 110. The light emitted from the light source 141 and incident on the projection lens 110 passes through the projection lens 110 and is irradiated in a predetermined light distribution pattern.

[0187] Incidentally, in this embodiment, the tail portion 140t of the substrate 140 is hidden beneath the plate-shaped cover portion 132p of the reflector unit 130. Therefore, the connector to which the tail portion 140t is connected is also hidden beneath the plate-shaped cover portion 132p. Consequently, in this embodiment, the light-shielding cover 132 of the reflector unit 130 is located between the projection lens 110 and the conductive member that supplies power to drive the light source 141, protecting the conductive member from sunlight incident from the projection lens 110.

[0188] Furthermore, as shown in Figure 27, in the vehicle headlight 1 of this embodiment, a portion of the side surface 132ps of the plate-shaped cover portion 132p of the reflector unit 130 overlaps with the bottom plate portion 121 of the lens holder 120 in the extending direction. If the side surface 132ps of the plate-shaped cover portion 132p does not overlap with the bottom plate portion 121 in the extending direction, and the plate-shaped cover portion 132p is located below the bottom plate portion 121, sunlight propagating toward the plate-shaped cover portion 132p may damage the lens holder 120. If the plate-shaped cover portion 132p is located above the bottom plate portion 121, sunlight propagating toward the plate-shaped cover portion 132p is reflected by the entire side surface 132ps of the plate-shaped cover portion 132p, and the reflected light may damage the lens holder 120. Therefore, as described above, by having the side surface 132ps of the plate-shaped cover portion 132p overlap with the bottom plate portion 121 in the extending direction, damage to the lens holder 120 by sunlight propagating toward the plate-shaped cover portion 132p can be suppressed. It is more preferable that the entire side surface 132ps of the plate-shaped cover portion 132p and the bottom plate portion 121 overlap in the extending direction of the bottom plate portion 121. Furthermore, if sunlight propagating toward the plate-shaped cover portion 132p is to be reflected by the side surface 132ps of the plate-shaped cover portion 132p, the plate-shaped cover portion 132p does not need to overlap with the bottom plate portion 121 in the extending direction.

[0189] Incidentally, in order to miniaturize vehicle headlights, integrated circuits used for switching light-emitting elements are sometimes mounted on the same substrate as the light-emitting elements. Since integrated circuits generally generate heat, it is preferable in this case as well to ensure that the heat is dissipated efficiently.

[0190] Therefore, in this embodiment, the vehicle headlight 1 of the heat sink 150 has a substrate-facing region 153 that faces the substrate 140, which includes a separation portion 155 that is separated from the substrate 140, and an arrangement portion 154 that is formed convexly toward the substrate 140 side than the separation portion 155 and on which the substrate 140 is placed. This arrangement portion 154 includes a light source-facing region 154e that faces the back surface of the light source mounting region 141a on which the light source 141 of the substrate 140 is mounted, an integrated circuit-facing region 154i that faces the back surface of the integrated circuit mounting region 142a on which the integrated circuit 142 of the substrate 140 is mounted, and a first connecting region 154c1 that connects the light source-facing region 154e and the integrated circuit-facing region 154i.

[0191] In this embodiment of the vehicle headlight 1, the heat generated from the light source 141 and the integrated circuit 142 is conducted through the substrate 140, mainly from the light source facing region 154e and the integrated circuit facing region 154i, to the heat sink 150, and dissipated. However, when the heat generated from the light source 141 and the integrated circuit 142 is conducted through the substrate 140, the region between the light source mounting region 141a and the integrated circuit mounting region 142a of the substrate 140 may be heated. In this embodiment of the vehicle headlight 1, the heat in this region can be conducted from the first connecting region 154c1 to the heat sink 150 for dissipation. Furthermore, by having a separation portion 155, it is possible to suppress the unnecessary return of heat conducted to the heat sink 150 back to the substrate 140. Therefore, the vehicle headlight 1 of this embodiment can efficiently dissipate heat.

[0192] Furthermore, in the vehicle headlight 1 of this embodiment, the light source opposing region 154e extends along the parallel direction of the multiple light-emitting elements 141e, and the integrated circuit opposing region 154i coincides with a straight line perpendicular to the line segment connecting the light-emitting elements 141e located at both ends. With this configuration, the extending direction of the light source opposing region 154e and the extending direction of the region including the integrated circuit opposing region 154i and the first connecting region 154c1 can be perpendicular to each other. Therefore, the substrate 140 can be stably placed on the heat sink 150.

[0193] Furthermore, in the vehicle headlight 1 of this embodiment, the separation portions 155 are located on both sides of the first connecting region 154c1 in the parallel direction of the light-emitting elements 141e. Therefore, compared to the case where the separation portions 155 are not located on both sides of the first connecting region 154c1, the return of heat conducted to the heat sink 150 to the substrate 140 can be further suppressed.

[0194] Furthermore, in the vehicle headlight 1 of this embodiment, the adjustment region 154a extends in the parallel direction of the light-emitting element 141e with respect to the integrated circuit facing region 154i, on the side opposite to the light source facing region 154e, and with a width wider than the integrated circuit facing region 154i, and the second connecting region 154c2 connects the adjustment region 154a and the integrated circuit facing region 154i. Therefore, by sandwiching the narrow integrated circuit facing region 154i between the light source facing region 154e and the adjustment region 154a, which extend in the same direction, the substrate 140 can be stably positioned on the heat sink 150.

[0195] Although the fourth aspect of the present invention has been described using the third embodiment as an example, the fourth aspect of the present invention is not limited thereto.

[0196] For example, in the third embodiment, a substrate 140 having a tail portion 140t that functions as a card edge connector was used. However, the fourth aspect of the present invention is not limited to this, and other substrates may be used. Figure 28 shows a modified example of the substrate 140. When describing this modified example, components that are the same as or equivalent to those in the third embodiment are given the same reference numerals unless otherwise specified, and redundant descriptions are omitted. As shown in Figure 28, the substrate 140 of this modified example differs from the substrate 140 of the third embodiment in that it does not have a tail portion 140t and has a socket 146 that includes a plurality of terminals for inputting power supplied to the integrated circuit 142 and each of the light-emitting elements 141e. Also, in Figure 28, the plurality of light-emitting elements 141e of the light source 141 are arranged in two stages, and are arranged in parallel in the left-right direction in each stage. The socket 146 has terminals inside and is a conductive member that supplies power to drive the light source 141. In this modified example as well, the socket 146 is hidden below the plate-shaped cover portion 132p of the reflector unit 130. Therefore, in the example shown in Figure 28, the light-shielding cover 132 of the reflector unit 130 is positioned between the projection lens 110 and the conductive member that supplies power to drive the light source 141, protecting the conductive member from sunlight incident from the projection lens 110.

[0197] Furthermore, although the third embodiment was described as a configuration in which the light source 141 consists of multiple light-emitting elements 141e, the light source 141 may consist of a single light-emitting element.

[0198] According to a first aspect of the present invention, a luminaire that can easily form a predetermined light distribution pattern is provided, which can be used in fields such as lighting. Furthermore, according to a second aspect of the present invention, a vehicle headlight that can reduce the number of parts while suppressing a decrease in visibility is provided, according to a third aspect of the present invention, a vehicle headlight that can suppress damage to conductive members by sunlight at low cost is provided, and according to a fourth aspect of the present invention, a vehicle headlight that can efficiently dissipate heat is provided, which can be used in fields such as automobiles.

Claims

1. A substrate on which a light source is mounted, A heat sink on which the aforementioned substrate is placed, A reflector unit that presses the substrate against the heat sink and reflects a portion of the light emitted from the light source, Equipped with, The substrate has recesses on each of its opposing sides, The light source is located inward from the bottom of each of the recesses. The reflector unit presses both sides of each recess in the substrate, which are located outside the bottom of each recess. A lighting fixture characterized by the following features.

2. The heat sink has protrusions that are inserted into each of the recesses. The luminaire according to feature 1.

3. The reflector unit has a flat opposing surface facing the substrate and an opening that penetrates from the opposing surface to the surface opposite to the substrate side. The light source overlaps with the aperture. The luminaire according to feature 1 or 2.

4. The opposing surface extends to the outer edge of the substrate-side surface of the reflector unit. The luminaire according to feature 3.

5. The aforementioned board further includes a connector mounted on it, The reflector unit is not formed on the side of the connector opposite to the light source side. The luminaire according to feature 1 or 2.

6. A substrate on which a light source is mounted, A heat sink on which the aforementioned substrate is placed, A reflector unit that presses the substrate against the heat sink and reflects a portion of the light emitted from the light source, Equipped with, The substrate has recesses on each of its opposing sides, The light source is located inward from the bottom of each of the recesses. The reflector unit presses against the portion of the substrate that is outside the bottom of each of the recesses, The heat sink has protrusions that are inserted into each of the recesses. A lighting fixture characterized by the following features.

7. A first light source emits light from a planar emission surface to form the light distribution pattern of the low beam, A second light source is located below the first light source and emits light from a planar emission surface that forms a high beam light distribution pattern with the light emitted from the first light source, A substrate on which the first light source and the second light source are mounted, A reflector unit positioned in front of the aforementioned substrate, A projection lens positioned in front of the reflector unit, Equipped with, The reflector unit comprises a first reflector positioned between the first light source and the second light source, with both its upper and lower surfaces being reflective, and a pair of second reflectors positioned above and below the first reflector. The perpendicular line to the emission surface of one of the first and second light sources moves away from the first reflector in the forward direction, while the perpendicular line to the emission surface of the other light source moves towards the first reflector in the forward direction. Of the light emitted from one of the light sources, some of the light passes between one of the reflective surfaces of the first reflector and one of the second reflectors and is directly incident on the projection lens, another portion of the light is reflected toward the projection lens at the portion of the one reflective surface of the first reflector including the front end, and yet another portion of the light is reflected by one of the second reflectors and reflected toward the projection lens at the portion of the one reflective surface of the first reflector including the front end. Of the light emitted from the other light source, some light passes between the other reflective surface of the first reflector and the other second reflector and is directly incident on the projection lens, another portion of the light is reflected toward the projection lens at the portion of the other reflective surface of the first reflector including the front end, and yet another portion of the light is reflected toward the projection lens at the other second reflector. A vehicle headlight characterized by the following features.

8. The aforementioned one light source is the first light source. The vehicle headlight according to feature 7.

9. Of the light emitted from one of the light sources, the other portion of the light is reflected towards the first reflector at the first second reflector with a divergence angle smaller than that at the incident light source. The vehicle headlight according to claim 7 or 8.

10. Of the light emitted from the other light source, a portion of that other light is reflected toward the projection lens at the second reflector of the other light source with a divergence angle greater than that at the incident light source. The vehicle headlight according to claim 7 or 8.

11. The substrate further comprises an integrated circuit mounted thereon that adjusts the power supplied to at least one of the first light source and the second light source, The reflector unit has a cover portion that covers the integrated circuit. The vehicle headlight according to claim 7 or 8.

12. Light source and A reflector unit having a reflecting part that reflects light emitted from the light source downward and forward toward the front, A projection lens through which the light reflected by the reflective portion is transmitted, A conductive member positioned below the reflective portion, A lens holder that holds the projection lens, Equipped with, The reflector unit has a light-shielding cover that is formed integrally with the reflective portion and is located between the projection lens and the conductive member below the reflective portion. The lens holder has a bottom plate portion that extends from the light-shielding cover side toward the projection lens side, The light-shielding cover includes a plate-shaped cover portion that extends along the extending direction of the bottom plate portion, At least a portion of the side surface of the plate-shaped cover portion overlaps with the bottom plate portion in the extending direction. A vehicle headlight characterized by the following features.

13. The width of the bottom plate portion in the left-right direction is greater than that of the plate-shaped cover portion. A recess is formed at the edge of the bottom plate portion on the side of the plate-shaped cover portion, into which a part of the plate-shaped cover portion fits. The vehicle headlight according to feature 12.

14. The upper surface of the plate-shaped cover portion scatters and reflects the incident light. The vehicle headlight according to claim 12 or 13.

15. The light-shielding cover has a light-scattering portion between the reflective portion and the plate-shaped cover portion that scatters and reflects incident light. The vehicle headlight according to claim 12 or 13.

16. The width of the plate-shaped cover portion in the left-right direction is greater than the width of the light scattering portion in the left-right direction. Each of the left and right ends of the plate-shaped cover extends further back than the light-scattering portion. The vehicle headlight according to feature 15.

17. The light-shielding cover has side cover portions that extend rearward and upward from the rear end of each of the aforementioned ends. The vehicle headlight according to feature 16.

18. A substrate on which a light source and an integrated circuit that switches the power supply to the light source are mounted, A heat sink on which the aforementioned substrate is placed, Equipped with, The substrate-facing region of the heat sink facing the substrate includes a separation portion that is separated from the substrate, and an arrangement portion that is formed convexly toward the substrate side than the separation portion and on which the substrate is placed. The arrangement portion includes a light source facing region facing the back surface of the area on which the light source is mounted on the substrate, an integrated circuit facing region facing the back surface of the area on which the integrated circuit is mounted on the substrate, and a first connecting region connecting the light source facing region and the integrated circuit facing region. The light source includes a plurality of light-emitting elements arranged in parallel with each other, The light source opposing region extends along the parallel direction of the plurality of light-emitting elements, The region opposite the integrated circuit coincides with a straight line perpendicular to the line segment connecting the light-emitting elements located at both ends, The separation portions are located on both sides of the first connecting region in the parallel direction. A vehicle headlight characterized by the following features.

19. The arrangement portion includes an adjustment region extending in the parallel direction with a width wider than the integrated circuit facing region, on the side opposite to the light source facing region with respect to the integrated circuit facing region, and a second connecting region connecting the adjustment region and the integrated circuit facing region. The vehicle headlight according to feature 18.

Images