Reflector and optical unit

Abstract

A reflector (16) is a resin reflector that is to be fastened to a heat sink such that a principal surface is directed toward the front of a vehicle. An opening (16b) through which light emitted from a light source is to pass is formed at a center part in the longitudinal direction, a pair of fastening parts (16c) that are to be fastened to the heat sink are formed at respective end parts in the longitudinal direction, and reflection parts that protrude to the front and reflect light that has passed through the opening are formed between the opening (16b) and the pair of fastening parts (16c). In a front view, the reflection parts at least partially overlap a rectangular region (S) that has the pair of fastening parts (16c) at respective ends.

Description

Reflector and Optical Unit

[0001] The present disclosure relates to a reflector and an optical unit.

[0002] Conventionally, a lighting fixture unit mainly composed of a heat sink, a substrate, a reflector unit, a projection lens, and a holder has been devised (see Patent Document 1). In this lighting fixture unit, the reflector unit presses the substrate against the heat sink, and the substrate is fixed to the heat sink. Further, the reflector unit is formed with an opening through which light emitted from a light-emitting element mounted on the substrate passes forward, and a reflecting surface provided so as to project forward from both left and right sides of the opening.

[0003] International Publication No. 2024 / 004959

[0004] However, when a plurality of components including optical components are mounted on a heat sink as in the above-described lighting fixture unit, if the shapes of the components, the portions where the components contact each other, the portions where the components are fastened, etc. are not properly considered, the reflecting surface may be deformed when the lighting fixture unit is assembled.

[0005] One object of the present disclosure is to provide a new technology in which a reflector or a unit including a reflector is less likely to be deformed.

[0006] A reflector according to an aspect of the present disclosure is a resin-made reflector arranged such that the main surface faces forward of the vehicle and fastened to a heat sink, in which an opening through which light emitted from a light source passes is formed at the central portion in the longitudinal direction, a pair of fastening portions formed at both end portions in the longitudinal direction and fastened to the heat sink, and a reflecting portion formed so as to project forward from between the pair of fastening portions and the opening and reflecting the light that has passed through the opening, and the reflecting portion at least partially overlaps a rectangular region having the pair of fastening portions at both ends in a front view.

[0007] According to this aspect, since the reflecting portion is included in the rectangular region having the pair of fastening portions at both ends in the front view of the reflector, deformation of the reflecting portion is suppressed as compared with the case where the reflecting portion is not included in the rectangular region.

[0008] Another aspect of the present disclosure is an optical unit. This optical unit comprises a heat sink, a substrate on which a light source is mounted and placed at a predetermined position on the heat sink, a lens for polarizing light emitted from the light source, and the above-mentioned reflector fastened to the heat sink with the substrate and lens sandwiched between the heat sink. The lens is a rectangular resin plate and has four contact portions at its four corners that are crushed while in contact with the back surface of the reflector when sandwiched between the substrate and the reflector. The four contact portions are included in the rectangular region.

[0009] According to this embodiment, when fastening the reflector, the load can be applied relatively evenly to the four contact points of the lens, so that the lens can be fixed in the desired position and orientation.

[0010] Any combination of the above components, as well as conversions of the expressions of this disclosure between manufacturing methods, devices such as luminaires and lighting fixtures, light-emitting modules, light sources, etc., are also valid embodiments of this disclosure.

[0011] According to this disclosure, deformation of the reflector or the unit containing the reflector can be suppressed.

[0012] Figure 1 is a perspective view of a vehicle light fixture according to this embodiment. Figure 2 is an exploded perspective view of the vehicle light fixture shown in Figure 1. Figure 3 is a front view of the reflector according to this embodiment. Figure 4 is a horizontal cross-sectional view of the optical unit according to this embodiment. Figure 5A is an enlarged cross-sectional view showing the state of the fastening portion in area A of Figure 4 before it is fastened with screws. Figure 5B is an enlarged cross-sectional view showing the state of the fastening portion in area A of Figure 4 after it has been fastened with screws. Figure 6 is a schematic diagram illustrating the state in which the resin plate according to this embodiment is in contact with the back of the reflector. Figure 7 is an enlarged view of area B of Figure 4.

[0013] The present disclosure will be described below with reference to the drawings, based on preferred embodiments. The same or equivalent components, members, and processes shown in each drawing will be denoted by the same reference numerals, and redundant descriptions will be omitted as appropriate. Furthermore, the embodiments are illustrative and not limiting to the invention, and not all features or combinations thereof described in the embodiments are necessarily essential to the invention.

[0014] Figure 1 is a perspective view of a vehicle light fixture according to this embodiment. Figure 2 is an exploded perspective view of the vehicle light fixture shown in Figure 1. The vehicle light fixtures shown in Figures 1 and 2 are vehicle headlights and are configured to form both low beam and high beam light distribution patterns.

[0015] The vehicle light fixture 10 comprises a projection lens 12, a lens holder 14, a reflector 16, a circuit board 18, and a heat sink 20. The projection lens 12 is mounted in a predetermined position on the lens holder 14. The projection lens 12 is manufactured by injection molding using a resin material with high transparency and heat resistance, such as acrylic or polycarbonate. The lens holder 14 is fastened to the heat sink 20 by screws 22.

[0016] Figure 3 is a front view of a reflector according to this embodiment. The reflector 16 is made of a resin material. The reflector 16 has a horizontally elongated base surface portion 16a facing in the front-rear direction, an opening 16b formed in the center of the reflector 16, and lateral reflective portions 16d provided so as to protrude forward from both the left and right sides of the opening 16b.

[0017] A plate-shaped member, a shade 24, is attached to the lower surface of the lateral reflector 16d, and it protrudes forward from the opening 16b. The shade 24 is held by the reflector 16 so that its plate surface is aligned with the horizontal direction of the vehicle.

[0018] The circuit board 18 includes a first light source 30a having a plurality of light-emitting elements 28a arranged in a horizontal row for forming a light distribution pattern for low beams, a second light source 30b having a plurality of light-emitting elements 28b arranged in a horizontal row for forming a light distribution pattern for high beams, and a drive circuit (not shown) for driving each light-emitting element.

[0019] The second light source 30b is positioned adjacent to the first light source 30a. The first light source 30a is located on the upper side, and the second light source 30b is located on the lower side. Here, the light source located on the upper side refers to the light source located on the upper vertical side of the vehicle when the vehicle lighting fixture is mounted on the vehicle, among the multiple stages of light sources. The light source located on the lower side refers to the light source located on the lower vertical side of the vehicle when the vehicle lighting fixture is mounted on the vehicle, among the multiple stages of light sources. The drive circuit is a combination of passive elements such as capacitors and coils, active elements such as transistors and diodes, IC chips, memory, etc., and functions as a control unit that controls the on / off switching of the first light source 30a and the second light source 30b. The circuit board 18 is the mounting section on which each light source is mounted, and is fixed to a predetermined position on the heat sink 20.

[0020] In front of the first light source 30a and the second light source 30b, a resin plate 32 is positioned which functions as a lens that polarizes the light emitted from the first light source 30a and the second light source 30b. Specifically, the resin plate 32 has lens portions formed laterally, corresponding to the number of light sources in the first light source 30a and the second light source 30b, which polarize the light from the light sources in a predetermined direction. The light transmitted through the resin plate 32 forms the light distribution pattern of the vehicle lamp by a component that directly enters the projection lens 12 and a component that is reflected by the shade 24 or the side reflector 16d before entering the projection lens. The resin plate 32 is sandwiched between the reflector 16 and the circuit board 18. In this state, the positional relationship of each component is determined by fastening the reflector 16 to the heat sink 20 with screws 36.

[0021] The optical unit 40 according to this embodiment comprises, among the components constituting the aforementioned vehicle lighting device 10, a metal heat sink 20, a circuit board 18 on which a first light source 30a and a second light source 30b are mounted, placed at a predetermined position on the heat sink 20, a resin plate 32 on which light emitted from each light source is transmitted as a lens, placed at a predetermined position on the circuit board 18, and a resin reflector 16 having a seating portion that sits on the circuit board 18 with the resin plate 32 in between. Here, "on the circuit board 18" is in the direction perpendicular to the main surface on which the light source 30a and the second light source 30b are mounted (in this embodiment, the direction toward the front of the vehicle), and does not necessarily coincide with the vertical direction of the vehicle.

[0022] Figure 4 is a horizontal cross-sectional view of the optical unit according to this embodiment. Figure 5A is an enlarged cross-sectional view showing the state of the fastening portion in area A of Figure 4 before it is fastened with screws. Figure 5B is an enlarged cross-sectional view showing the state of the fastening portion in area A of Figure 4 after it has been fastened with screws.

[0023] As shown in Figure 4, the reflector 16 has a seating portion 16e on the side opposite to the side on which the lateral reflecting portion 16d is provided. The seating portion 16e is seated on the upper surface of the circuit board 18. The reflector 16 also has a pair of fastening portions 16c formed outside the longitudinal end (left-right direction in Figure 4) of the resin plate 32. In other words, the lateral reflecting portion 16d is formed between the pair of fastening portions 16c and reflects light that has passed through the resin plate 32.

[0024] Next, the fastening portion 16c will be described in detail. As shown in Figure 5A, in each of the pair of fastening portions 16c, when the seating portion 16e is seated on the circuit board 18 and before fastening with the screws 36, a gap G is formed between it and the heat sink 20. When such a fastening portion 16c is fastened to the heat sink 20 with screws 36 (see Figure 5B), the contact surface 16f on the back side of the fastening portion 16c comes into contact with the heat sink 20. At that time, the fastening portion 16c deforms in the direction of arrow B, so the lateral reflecting portion 16d in the center of the reflector 16 may be displaced in the direction of arrow C. If the lateral reflecting portion 16d is displaced in the direction of arrow C, the light reflected by the lateral reflecting portion 16d will be deviated from the desired direction, which may cause glare to pedestrians or oncoming vehicles.

[0025] Therefore, in the reflector 16 according to this embodiment, a deformation transmission suppression portion is formed between the fastening portion 16c and the lateral reflecting portion 16d to suppress the transmission of the deformation effect at the fastening portion 16c to the lateral reflecting portion 16d. As a result, the deformation effect at the fastening portion 16c when the reflector 16 is fastened to the heat sink 20 is less likely to be transmitted to the lateral reflecting portion 16d, and the influence of the shift in the direction of the light reflected by the lateral reflecting portion 16d on the light distribution pattern can be reduced. Specifically, the deformation transmission suppression portion according to this embodiment is a slit 16g formed near the fastening portion 16c. As a result, the deformation transmission suppression portion can be realized with a simple shape. The deformation transmission suppression portion may also be realized by forming a thin-walled portion or a hollowed-out portion between the fastening portion 16c and the lateral reflecting portion 16d.

[0026] Furthermore, the reflector 16 has an arc-shaped step 16h recessed on the contact surface 16f side between the fastening portion 16c and the region where the slit 16g is formed. This reduces the gap G between the fastening portion 16c of the reflector 16 and the heat sink 20 before fastening. In other words, the amount of deflection of the reflector 16 in the B direction when fastened is reduced.

[0027] Furthermore, the reflector 16 can also be considered as a component having the following characteristics. For example, the reflector 16 according to this embodiment is a resin component fastened to the heat sink 20, with its main surface, the base surface portion 16a, facing forward of the vehicle. An opening 16b is formed in the center of the longitudinal direction through which light emitted from each light source passes. A pair of fastening portions 16c are formed at both ends in the longitudinal direction and fastened to the heat sink 20. A lateral reflecting portion 16d is formed to protrude forward from between the pair of fastening portions 16c and the opening 16b and reflects the light that has passed through the opening 16b. A slit 16g is formed between the fastening portion 16c and the lateral reflecting portion 16d to suppress the transmission of the deformation effect at the fastening portion 16c to the lateral reflecting portion 16d.

[0028] It can also be considered as a method for manufacturing the optical unit 40 equipped with the aforementioned reflector. For example, the method for manufacturing the optical unit 40 according to this embodiment includes the steps of: placing a circuit board 18 on which each light source is mounted in a predetermined position on a metal heat sink 20; placing a resin plate 32 through which light emitted from each light source is transmitted in a predetermined position on the circuit board 18; seating a resin reflector 16 on the circuit board 18 with the resin plate 32 in between; and fastening the reflector 16 to the heat sink 20 with screws 36. The fastening step involves fastening the reflector 16 to the heat sink 20 while bending the fastening portion 16c toward the heat sink. By doing so, the resin plate 32 can be firmly fixed between the reflector 16 and the heat sink 20 by fastening the reflector 16 to the heat sink 20 while bending the fastening portion 16c of the reflector 16.

[0029] Furthermore, the reflector 16 can be considered as a component having the following characteristics. For example, as shown in Figure 3, the lateral reflective portion 16d of the reflector 16 according to this embodiment overlaps, at least in part, with a rectangular region S with a pair of fastening portions 16c at both ends when viewed from the front. Here, the rectangular region S includes the entire region (a track shape) sandwiched between the pair of fastening portions 16c, which have semicircular outer edges, as shown in Figure 3, and the lateral reflective portion 16d partially overlaps with this rectangular region S. In addition, the rectangular region S' of other forms may include the entire region sandwiched between the through holes 16k through which the screws 36 of the fastening portions 16c pass. Furthermore, although the outer shape of the pair of fastening portions 16c is semicircular in this embodiment, the outer shape is not limited to a semicircle. The outer shape of the pair of fastening portions 16c is not limited to a semicircle as long as a region of a predetermined diameter can be secured from the center of the head of the screw 36. For example, the outer shape may be a rectangle formed by two 90-degree vertices. Here, the region of a predetermined diameter can be, for example, a region with a diameter of about 1.0 to 2.0 times the outer diameter of the head of the screw 36.

[0030] As a result, in a front view of the reflector 16, the lateral reflective portion 16d is included in a rectangular region S (hereinafter, the rectangular region S and the rectangular region S' together will be referred to as the rectangular region S) with the pair of fastening portions 16c at both ends. Therefore, compared to the case where the lateral reflective portion 16d is not included in the rectangular region S, deformation of the lateral reflective portion 16d during fastening is suppressed.

[0031] Furthermore, the reflector 16 is further equipped with a plate-shaped shade 24 attached to the lower surface of the lateral reflector 16d. The shade 24 blocks a portion of the light passing through the opening 16b. If the lateral reflector 16d is provided in the lower half of the reflector, the shade 24 may be attached to the upper surface of the lateral reflector 16d. In this embodiment, the shade 24 overlaps with the aforementioned rectangular region S in a front view from the front of the vehicle, at least in part. This further suppresses deformation not only of the lateral reflector 16d but also of the shade 24.

[0032] Furthermore, the slits 16g in this embodiment are provided at four symmetrical positions centered on the rectangular region S. This ensures that the effect of the deformation transmission suppression unit is evenly transmitted to the rectangular region S.

[0033] Figure 6 is a schematic diagram illustrating the state in which the resin plate 32 according to this embodiment is in contact with the back surface of the reflector 16. Figure 7 is an enlarged view of area B in Figure 4.

[0034] The optical unit according to this embodiment can be considered as a device having the following features. As shown in Figure 4, the optical unit 40 comprises a heat sink 20, a circuit board 18 on which a light source is mounted and placed at a predetermined position on the heat sink 20, a rectangular resin plate 32 that polarizes light emitted from the light source and is placed at a predetermined position on the circuit board 18, and a reflector 16 that is fastened to the heat sink 20 with the circuit board 18 and the resin plate 32 sandwiched between the heat sink 20.

[0035] As shown in Figures 6 and 7, the resin plate 32 is sandwiched between the circuit board 18 and the reflector 16 and has four contact portions 32a at its four corners that are crushed while in contact with the back surface 16m of the reflector 16. The four contact portions 32a in this embodiment are contained within a rectangular region S. The contact portions 32a have projections 32c that protrude from the main surface 32b of the resin plate 32 and annular grooves 32d that surround the projections 32c.

[0036] The resin plate 32 can be made of a material that causes the projections 32c to deform when the reflector 16 is fastened to the heat sink 20 with the projections 32c in contact with the back surface 16m of the reflector 16. Elastic or plastically deformable materials can be used. Specifically, the resin plate 32 is made of silicone resin. This allows the load to be applied relatively evenly to the four contact points 32a of the resin plate 32 when fastening the reflector 16, thus fixing the resin plate 32 in the desired position and orientation. Furthermore, the projections 32c deform preferentially when the reflector 16 is pressed against the resin plate 32, thereby suppressing deformation of the reflector 16.

[0037] Although the present disclosure has been described above with reference to the embodiments described above, the present disclosure is not limited to the embodiments described above, and includes combinations and substitutions of the configurations of the embodiments as appropriate. Furthermore, it is possible to rearrange the combinations and processing order in the embodiments as appropriate based on the knowledge of those skilled in the art, and to make modifications such as various design changes to the embodiments, and such modified embodiments may also be included in the scope of the present disclosure.

[0038] This application claims priority under Japanese Patent Application No. 2024-226800, filed on 23 December 2024, and incorporates all the provisions contained herein.

Claims

1. A resin reflector positioned with its main surface facing the front of the vehicle and fastened to a heat sink, having an opening formed in the center of its longitudinal direction through which light emitted from a light source passes, a pair of fastening parts formed at both ends in the longitudinal direction and fastened to the heat sink, and a reflective part formed to protrude forward from between the pair of fastening parts and the opening and to reflect the light that has passed through the opening, wherein, in a front view, the reflective part overlaps at least a portion with a rectangular region with the pair of fastening parts at both ends.

2. The reflector according to claim 1, further comprising a plate-shaped shade attached to the lower or upper surface of the reflective portion, wherein the shade blocks a portion of the light passing through the opening.

3. The reflector according to claim 2, wherein the shade, in a front view as seen from the front of the vehicle, overlaps at least a portion with a rectangular area having the pair of fastening parts at both ends.

4. The reflector according to any one of claims 1 to 3, wherein a deformation transmission suppression portion is formed between the fastening portion and the reflective portion to suppress the transmission of the effects of deformation at the fastening portion to the reflective portion.

5. The reflector according to claim 4, wherein the deformation transmission suppression portion is a slit formed near the fastening portion.

6. The reflector according to claim 5, wherein a recessed step is formed between the fastening portion and the region where the slit is formed, on the rearward side of the vehicle.

7. The reflector according to claim 5 or 6, wherein the slits are provided at four locations symmetrically positioned around the rectangular region.

8. An optical unit comprising: a heat sink; a substrate on which a light source is mounted, placed at a predetermined position on the heat sink; a lens for polarizing light emitted from the light source, placed at a predetermined position on the substrate; and a reflector according to any one of claims 1 to 6, fastened to the heat sink with the substrate and the lens sandwiched between the heat sink, wherein the lens is a rectangular resin plate, and has four contact portions at its four corners that are crushed while in contact with the back surface of the reflector when sandwiched between the substrate and the reflector, and the four contact portions are included in the rectangular region.

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