JP7556209B2 - Vehicle lighting fixtures - Google Patents

Description

The present invention relates to a vehicle lamp.

There is a known vehicle lamp equipped with a vehicle light guide that guides light from a light source and emits light (see, for example, Patent Document 1). In such a vehicle light guide, light emitted from a light source is incident on an entrance surface provided at an end of the vehicle light guide in the longitudinal direction, and the incident light is guided along the longitudinal direction and emitted from a side surface.

JP 2018-205651 A

Patent Document 1 describes a configuration in which the distance between the light source and the incident surface of the vehicle light guide is reduced in order to efficiently use the light emitted from the light source. However, when multiple light sources are provided and the distance between the multiple light sources and the incident surface of the vehicle light guide is reduced, it is necessary to consider the effects of heat generated by the multiple light sources.

The present invention has been made in consideration of the above, and aims to provide a vehicle lamp that can efficiently utilize the light from multiple light sources while taking into account the effects of heat generated by the multiple light sources.

The vehicle lamp according to the present invention includes a first light guiding section having a plurality of light sources, an incident surface on which light from the plurality of light sources is incident, an outer wall surface connected to the outer periphery of the incident surface and internally reflecting the light incident from the incident surface, and an inner wall surface provided inside the outer wall surface facing the outer wall surface and internally reflecting the light incident from the incident surface, and a second light guiding section provided integrally with the first light guiding section and guiding and emitting the light guided by the first light guiding section, the first light guiding section being formed using a material having a higher heat resistance than the second light guiding section.

The first light guide may have a plurality of branching sections that branch toward the light source, and the entrance surface may be provided on each of the branching sections.

The first light guide may also have a shape in which the multiple branch sections extend toward the light source.

The light sources may also be arranged on a circumference.

The plurality of light sources may include light sources that emit light of different wavelengths, and the light sources that emit light of different wavelengths may be arranged adjacent to each other in the circumferential direction.

Additionally, the multiple light sources may be arranged at equal intervals in the circumferential direction.

The first light guide may also be formed using silicone resin.

The present invention makes it possible to provide a vehicle lamp that can efficiently utilize the light from multiple light sources while taking into account the effects of heat generated by the multiple light sources.

FIG. 1 is a perspective view showing an example of a vehicle lamp according to the present embodiment. FIG. 2 is a diagram showing an example of the arrangement of light sources. FIG. 3 is a perspective view illustrating an example of a first light guiding unit. FIG. 4 is a perspective view illustrating an example of a first light guiding section. FIG. 5 is a cross-sectional view taken along line AA in FIG. FIG. 6 is a diagram showing a partial configuration of a vehicle lamp according to a modified example. FIG. 7 is a diagram showing a partial configuration of a vehicle lamp according to a modified example. FIG. 8 is a diagram showing a partial configuration of a vehicle lamp according to a modified example. FIG. 9 is a diagram showing a partial configuration of a vehicle lamp according to a modified example. FIG. 10 is a diagram showing an arrangement of light sources according to a modified example.

Below, an embodiment of a vehicle lamp according to the present invention will be described with reference to the drawings. Note that the present invention is not limited to this embodiment. Furthermore, the components in the following embodiments include those that are easily replaceable by a person skilled in the art, or those that are substantially the same.

Fig. 1 is a perspective view showing an example of a vehicle lamp 100 according to this embodiment. As shown in Fig. 1, the vehicle lamp 100 includes a light source 10, a first light guiding section 20, a second light guiding section 30, and a heat dissipation member 40. Examples of the vehicle lamp 100 include a clearance lamp, a turn signal lamp, a daytime running lamp, a tail lamp, a stop lamp, or a combination of these various lamps. The vehicle lamp 100 is housed in a lamp chamber (not shown).

[light source]
In this embodiment, the light source 10 is a semiconductor light source such as an LED or an OLED (organic electroluminescence), a laser light source, or the like. The light source 10 is supported by a heat dissipation member 40 described later. The light source 10 has a light emitting surface 11 that emits light. The light emitting surface 11 is disposed opposite to an incident surface 23 of a first light guiding section 20 described later. FIG. 2 is a diagram showing an example of the arrangement of the light source 10. As shown in FIG. 2, a plurality of light sources 10 are arranged on a circumference P centered on a point O. In this embodiment, a configuration in which, for example, five light sources 10 are arranged is given as an example, but is not limited to this. Four or less, or six or more may be arranged. The plurality of light sources 10 are arranged, for example, at equal pitches in the circumferential direction of the circumference P. This allows heat generated when light is irradiated from the light source 10 to be dispersed.

[First light guiding section]
The first light guiding section 20 guides light from the light source 10 to the second light guiding section 30. The first light guiding section 20 is supported by a bracket (not shown) arranged in a lamp house. Figures 3 and 4 are perspective views showing an example of the first light guiding section 20. Figure 3 shows a state seen from the second light guiding section 30 side. Figure 4 shows a state seen from the light source 10 side.

3 and 4, the first light guiding section 20 is formed, for example, in a cylindrical shape centered on the central axis AX. The first light guiding section 20 is formed using a material having a higher heat resistance than the second light guiding section 30 described later. In this embodiment, the first light guiding section 20 is formed using a material such as silicon resin or glass. The first light guiding section 20 is integrally molded with the second light guiding section 30 described later. By integral molding, the bonding strength between the first light guiding section 20 and the second light guiding section 30 can be ensured. In addition, when silicon resin is used as the first light guiding section 20, the fluidity during molding is improved, so that even a first light guiding section 20 with a small diameter can be easily formed. In addition, when silicon resin is used as the first light guiding section 20, the adhesion with the second light guiding section 30 is improved, so that it is possible to integrate the first light guiding section 20 with the second light guiding section 30 without providing a separate fixing member.

The first light guiding section 20 has a base section 21 and a branch section 22. The base section 21 is provided at the connection section with the second light guiding section 30. The branch section 22 branches into multiple sections from the base section 21 toward the light source 10 side. The branch sections 22 are provided in the same number as the number of light sources 10, for example. In this embodiment, five branch sections 22 are provided.

The first light guiding section 20 has an incident surface 23 at the tip of each branch section 22 on the light source 10 side. One incident surface 23 is provided corresponding to one light source 10. The incident surface 23 is provided opposite the light emitting surface 11 of each light source 10. Light from the light source 10 is incident on the incident surface 23.

The first light guiding section 20 has an outer wall surface 24 connected to the outer periphery of the incident surface 23. The outer wall surface 24 internally reflects the light incident from the incident surface 23. The outer wall surface 24 is formed in a cylindrical shape across the multiple branching sections 22. The outer wall surface 24 provided on each branching section 22 has the shape of a part of a cylindrical surface centered on the central axis AX.

The first light guiding section 20 has an inner wall surface 25 that faces the outer wall surface 24. The inner wall surface 25 internally reflects the light incident from the incident surface 23. The inner wall surface 25 is formed in a cylindrical shape across the multiple branching sections 22. The inner wall surface 25 provided in each branching section 22 has the shape of a part of a cylindrical surface centered on the central axis AX.

The first light guiding section 20 has side wall surfaces 26 that connect the outer wall surface 24 and the inner wall surface 25. The side wall surfaces 26 are arranged on both sides in the axial direction around the central axis AX. The side wall surfaces 26 internally reflect the light incident from the incident surface 23.

The first light-guiding section 20 can guide the light incident on the entrance surface 23 to the second light-guiding section 30 while being internally reflected by the outer wall surface 24, the inner wall surface 25, and the side wall surface 26.

Figure 5 is a cross-sectional view taken along the line A-A in Figure 4. As shown in Figure 5, the light source 10 is disposed close to the incident surface 23. For example, the light source 10 is disposed so that the distance between the incident surface 23 and the light emitting surface 11 of the light source 10 is 1 mm or less. The first light guiding section 20 is formed using a highly heat-resistant material such as silicone resin or glass, so that heat resistance against heat generated by the light source 10 can be ensured.

[Second light guiding section]
The second light guiding section 30 is provided integrally with the first light guiding section 20. The second light guiding section 30 guides and emits light from the first light guiding section 20. The second light guiding section 30 has an incident surface 31 and an exit surface 32. The light from the first light guiding section 20 is incident on the incident surface 31. The exit surface 32 emits the guided light. The second light guiding section 30 is formed using, for example, acrylic resin, polycarbonate resin, or the like.

[Heat dissipation material]
The heat dissipation member 40 has a light source fixing portion 41 and fins 42. The heat dissipation member 40 is formed using a metal material such as aluminum. The heat dissipation member 40 has the light source fixing portion 41 and the fins 42 molded integrally. The light source fixing portion 41 is, for example, flat plate-shaped, and supports the light source 10. The light source 10 is supported by the light source fixing portion 41 via a substrate (not shown). A plurality of fins 42 are provided on the light source fixing portion 41. The heat dissipation member 40 dissipates heat generated by the light source 10 from the light source fixing portion 41 to the outside via the fins 42. The heat dissipation member 40 supports the light source 10 at the position shown in FIG. 2. In this case, the heat of the light source 10 is dispersed, improving the heat dissipation performance. Therefore, the heat dissipation member 40 can be made smaller. In addition, even when the output of the light source 10 is increased, that is, the amount of heat generated from the light source 10 increases, the heat can be sufficiently dissipated.

The operation of the vehicle lamp 100 configured as above will be described. The light emitted from the light emitting surface 11 of each light source 10 enters the first light guiding section 20 from the incident surface 23 of the corresponding branch section 22. The light source 10 generates heat as the light is emitted. In this embodiment, the first light guiding section 20 is provided with an inner wall surface 25, so that the surface area of the first light guiding section 20 is larger than that of a configuration in which the inner wall surface 25 is not provided, and the heat dissipation of the first light guiding section 20 is improved. Therefore, the heat from the light source 10 is prevented from being transmitted to the second light guiding section 30. In order to efficiently guide the light from the light source 10, the second light guiding section 30 is made of a material such as acrylic that has a lower heat resistance than the first light guiding section 20, and is therefore susceptible to the effects of heat. In the configuration of this embodiment, the heat from the light source 10 is prevented from being transmitted to the second light guiding section 30, so that the second light guiding section 30 can be prevented from being affected by heat.

In addition, by improving the heat dissipation of the first light guiding section 20, the heat resistance of the first light guiding section 20 can be ensured compared to a configuration in which the inner wall surface 25 is not provided. Therefore, it is possible to arrange the light source 10 close to the incident surface 23, and the light from the light source 10 can be efficiently incident on the incident surface 23.

In addition, for example, if the output from the light source 10 is increased in order to improve the amount of light emitted by the vehicle lamp 100, the amount of heat generated by the light source 10 also increases. In contrast, in this embodiment, the heat dissipation properties of the first light guide section 20 are improved, so that the heat resistance of the first light guide section 20 can be sufficiently ensured.

In addition, by reducing the light-emitting area of the light source 10, the amount of light from the light source 10 can be increased relatively, and the area of the incident surface 23 can be reduced corresponding to the light-emitting area of the light source 10, making it possible to make the branching section 22 thinner. In this case, the multiple light sources 10 can be arranged at a distance from each other, improving heat dissipation. When silicone resin is used for the first light-guiding section 20, the elasticity of the silicone resin allows for a configuration that is less likely to break even when made thinner.

In this way, by taking into account the effects of heat generated by the light source 10, it is possible to efficiently utilize the light from the light source 10 in a variety of forms.

Light incident on the first light guiding section 20 is guided from the branch section 22 to the base section 21 while being internally reflected by the outer wall surface 24, the inner wall surface 25, and the side wall surface 26, and then enters the second light guiding section 30 from the base section 21 via the incident surface 31. By providing the inner wall surface 25 on the first light guiding section 20, it is possible to increase the number of times that the light incident from the incident surface 23 is internally reflected, compared to a configuration in which the inner wall surface 25 is not provided. This makes it possible to stabilize the optical path of the diffuse reflection of light, and makes it easier to control the light distribution, such as making the light emitted from the second light guiding section 30 uniform.

The light that enters the second light guide section 30 is guided while being internally reflected in the second light guide section 30, and is emitted to the outside from the emission surface 32. The light that is emitted from the emission surface 32 is irradiated, for example, toward the front side of the vehicle.

As described above, the vehicle lamp 100 according to this embodiment includes a first light guide section 20 having a plurality of light sources 10, an incident surface 23 on which light from the plurality of light sources 10 is incident, an outer wall surface 24 connected to the outer periphery of the incident surface 23 and internally reflecting the light incident from the incident surface 23, and an inner wall surface 25 provided inside the outer wall surface 24 and facing the outer wall surface 24 and internally reflecting the light incident from the incident surface 23, and a second light guide section 30 provided integrally with the first light guide section 20 and guiding and emitting the light from the first light guide section 20, and the first light guide section 20 is formed using a material having a higher heat resistance than the second light guide section 30.

According to this configuration, the first light guide section 20 having the incident surface 23 through which the light from the light source 10 is incident is formed using a material having a higher heat resistance than the second light guide section 30, so that heat resistance can be ensured compared to the case where the light from the light source 10 is directly incident on the second light guide section 30. In addition, by providing the inner wall surface 25 on the first light guide section 20, the surface area of the first light guide section 20 can be made larger than in a configuration in which the inner wall surface 25 is not provided. Therefore, the heat dissipation of the first light guide section 20 can be improved. This ensures the heat resistance of the first light guide section 20. Therefore, it is possible to arrange the light source 10 close to the incident surface 23, and the light from the light source 10 can be efficiently incident on the incident surface 23. In addition, for example, when the output from the light source 10 is increased in order to improve the light emission amount of the vehicle lamp 100, the amount of heat generated by the light source 10 also increases. In contrast, in this embodiment, the heat dissipation of the first light guide section 20 is improved, so that the heat resistance of the first light guide section 20 can be sufficiently ensured. In addition, by reducing the light emission area of the light source 10, the amount of light from the light source 10 can be relatively increased, and the area of the entrance surface 23 can be reduced corresponding to the light emission area of the light source 10. Therefore, it is possible to efficiently use the light from the multiple light sources 10 while taking into consideration the influence of heat generated by the multiple light sources 10. Furthermore, by providing the inner wall surface 25 on the first light guide section 20, the number of internal reflections of the light incident from the entrance surface 23 can be increased compared to a configuration in which the inner wall surface 25 is not provided. This makes it possible to stabilize the optical path of the diffuse reflection of light, and makes it easier to control the light distribution, such as making the light emitted from the second light guide section 30 uniform.

In the vehicle lamp 100 according to this embodiment, the first light guide section 20 has a plurality of branch sections 22 that branch toward the light source 10, and the incident surface 23 is provided on each of the branch sections 22. With this configuration, the light source 10 can be arranged at a position corresponding to the incident surface 23 of the branch section 22, so that the light source 10 can be dispersed. This allows the heat generated from the plurality of light sources 10 to be dispersed. In addition, when the first light guide section 20 is supported by a bracket, for example, openings of positions and dimensions corresponding to the plurality of branch sections 22 are formed in the bracket, and the branch sections 22 are inserted into the openings, so that each branch section 22 can be supported. In this case, the first light guide section 20 can be stably supported.

In the vehicle lamp 100 according to this embodiment, the multiple light sources 10 are arranged on a circumference. This allows the heat generated by the multiple light sources 10 to be efficiently dispersed.

In the vehicle lamp 100 according to this embodiment, the multiple light sources 10 are arranged at equal pitches in the circumferential direction. This allows the heat generated by the multiple light sources 10 arranged on the circumference to be dispersed more efficiently.

In the vehicle lamp 100 according to this embodiment, the first light guide section 20 is formed using silicone resin. This ensures high heat resistance.

The technical scope of the present invention is not limited to the above embodiment, and appropriate modifications can be made without departing from the spirit of the present invention. For example, the above embodiment has been described with an example of a configuration in which the first light guide section 20 has a base section 21 and a branch section 22, but is not limited to this.

Figure 6 is a diagram showing the configuration of a portion of a vehicle lamp 100A according to a modified example. As shown in Figure 6, a configuration may be adopted in which multiple first light guiding sections 20A are connected to a second light guiding section 30A. In this case, each first light guiding section 20A has the same configuration as the branching section 22 in the above embodiment. In other words, the first light guiding section 20A has an incident surface 23A, an outer wall surface 24A, and an inner wall surface 25A.

The second light guiding section 30A has a convex section 31A and a concave section 32A at the joint with the first light guiding section 20A. The convex section 31A is a section whose radial center section protrudes toward the first light guiding section 20A side. The concave section 32A is a section whose radial periphery section is relatively recessed on the opposite side of the first light guiding section 20A side with respect to the convex section 31A. A side section 33A is provided between the convex section 31A and the concave section 32A. The first light guiding section 20A has a part of the inner wall surface 25A joined to the side section 33A of the second light guiding section 30A, and an end surface 29A opposite to the incident surface 23A joined to the concave section 32A of the second light guiding section 30A.

The first light guiding section 20A is integrally molded with the second light guiding section 30A. By integrally molding, it is possible to ensure the bonding strength between the first light guiding section 20A and the second light guiding section 30A. In addition, since the first light guiding section 20A is bonded to the side section 33A of the second light guiding section 30, the bonding strength is further ensured.

In the above embodiment, the first light guide section 20 has been described with a configuration in which the multiple branch sections 22 extend linearly from the base section 21 along the central axis AX, but this is not limiting. Figure 7 is a diagram showing the configuration of a portion of a vehicle lamp 100B according to a modified example.

As shown in FIG. 7, the first light guiding section 20B has a base 21B and a branch section 22B. The branch section 22B has a shape that spreads outward in the radial direction from the base 21B toward the light source 10. The end of the branch section 22B on the light source 10 side protrudes outward in the radial direction beyond the outer peripheral surface of the base 21B. The first light guiding section 20B has an entrance surface 23B, an outer wall surface 24B, an inner wall surface 25B, and a side wall surface 26B in each branch section 22B. This configuration allows the light source 10 to be more dispersed, and therefore the heat generated by the light source 10 to be dispersed.

In the above embodiment, the first light guide section 20 is provided with a branch section 22 for each light source 10, but the present invention is not limited to this. Figure 8 shows the configuration of a portion of a vehicle lamp 100C according to a modified example.

As shown in FIG. 8, the first light guide 20C has a base 21C and a plate-shaped branch 22C that is branched into two. The branch 22C is provided with, for example, a rectangular incident surface 23C extending in one direction, an outer wall surface 24C, and an inner wall surface 25C. A plurality of light sources 10 are arranged facing the incident surface 23C along the longitudinal direction. With this configuration, the heat of the light sources 10 can be dispersed in the longitudinal direction of the incident surface 23C.

Figure 9 is a diagram showing a partial configuration of a vehicle lamp 100D according to a modified example. As shown in Figure 9, the first light guiding section 20D may have a base section 21D and a cylindrical section 22D. The cylindrical section 22D is configured by connecting the branch sections 22 described in the above embodiment in a cylindrical shape. The first light guiding section 20D has an entrance surface 23D, an outer wall surface 24D, and an inner wall surface 25D in the cylindrical section 22D. This configuration improves the impact resistance of the first light guiding section 20D.

In addition, in the configuration of the above embodiment, light sources that emit different types of light may be used. For example, a case will be described in which the vehicle lamp 100 has two functions, a clearance lamp and a turn signal lamp. FIG. 10 is a diagram showing the arrangement of light sources according to a modified example. As shown in FIG. 10, the light source 10P has a light-emitting surface 11P that emits white light that becomes the light of the clearance lamp, for example. The white light emitted from the light-emitting surface 11P of the light source 10P is irradiated to the outside of the vehicle, for example, via a light-guiding member. The light source 10Q has a light-emitting surface 11Q that emits orange (amber) light that becomes the light of the turn signal lamp, for example. The orange light emitted from the light-emitting surface 11Q of the light source 10Q is irradiated to the outside of the vehicle, for example, via a light-guiding member.

In the configuration shown in FIG. 10, multiple light sources 10P and multiple light sources 10Q are arranged on a circumference centered on point O. In addition, the light sources 10P and the light sources 10Q are arranged adjacent to each other in the circumferential direction. In other words, the light sources 10P and the light sources 10Q are arranged in a state where they are spaced apart from each other in the circumferential direction. In this case, the multiple light sources 10P are arranged in a distributed manner in the circumferential direction. In addition, the multiple light sources 10Q are arranged in a distributed manner in the circumferential direction. Therefore, in a case where one light source is turned on when the other is turned off, such as a turn signal lamp and a clearance lamp, the light sources that are turned on can be arranged at a distance from each other, so that heat can be dispersed. As a result, even if multiple functions are set in one vehicle lamp 100, the effect of heat from the light source can be suppressed and the light from the light source can be fully utilized.

In the above embodiment, the first light guiding section 20 and the second light guiding section 30 are integrally molded, but the present invention is not limited to this. For example, the first light guiding section 20 and the second light guiding section 30 may be formed separately and then integrated by fitting them together.

AX...central axis, P...circumference, 10, 10P, 10Q...light source, 11...light emitting surface, 20, 20A, 20B, 20C, 20D...first light guiding section, 21, 21B, 21C, 21D...base, 22, 22C...branching section, 22D...cylindrical section, 23, 23A, 23B, 23C, 23D, 31...incident surface, 24, 24A, 24B, 24C, 24D... Outer wall surface, 25, 25A, 25B, 25C, 25D...inner wall surface, 26, 26B...side wall surface, 29A...end surface, 30, 30A...second light guide section, 31A...convex portion, 32...emission surface, 32A...concave portion, 33A...side surface, 40...heat dissipation member, 41...light source fixing portion, 42...fin, 100, 100A, 100B, 100C, 100D...vehicle lamp

Claims (5)

A plurality of light sources;
a first light guiding section including an incident surface through which light from the plurality of light sources is incident, an outer wall surface connected to an outer periphery of the incident surface and internally reflecting the light incident from the incident surface, and an inner wall surface provided inside the outer wall surface and facing the outer wall surface, and internally reflecting the light incident from the incident surface;
a second light guiding section that is integral with the first light guiding section and guides the light from the first light guiding section and emits the light,
the first light guiding portion is formed using a material having a higher heat resistance than the second light guiding portion,
The plurality of light sources are arranged on a circumference centered on a central axis, for each of the entrance surfaces, and are arranged in a circumferential direction;
the first light guiding section has a plurality of branching sections branching in the circumferential direction toward the light source side,
The entrance surface is provided on each of the branching portions,
the outer wall surface of each of the branch portions is a part of a first cylindrical surface centered on the central axis,
The inner wall surface of each of the branched portions is a part of a second cylindrical surface having a smaller diameter than the first cylindrical surface and centered on the central axis,
Each of the branch portions has a side wall surface on both sides in a direction around the central axis,
The side wall surface connects the outer wall surface and the inner wall surface along a radial direction centered on the central axis, and internally reflects the light incident from the incident surface. The vehicular lamp according to claim 1 , wherein the second light guiding portion is cylindrical and has a center on the central axis and a same diameter as the first cylindrical surface. The plurality of light sources include light sources that emit light of different wavelengths,
The vehicular lamp according to claim 1 or 2 , wherein the light sources emitting light of different wavelengths are arranged adjacent to each other in a circumferential direction. The vehicular lamp according to claim 1 , wherein the light sources are arranged at equal intervals in a circumferential direction. The vehicular lamp according to claim 1 , wherein the first light guiding portion is made of a silicone resin.

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