Vehicle lighting

Abstract

To ensure uniformity of light without causing a surge in manufacturing costs. [Solution] The device comprises a light source that emits light, and a light guide having a plurality of light guide sections, one end face in the longitudinal direction formed as an incident surface and the other end face in the longitudinal direction formed as an end surface, which guide the light emitted from the light source from the incident surface to the end surface. The light guide has a reflection step that internally reflects the guided light and an exit surface that emits the light reflected by the reflection step. The plurality of light guide sections are composed of at least one reference light guide section that extends from the incident surface to the end surface and a plurality of converging light guide sections that merge with other light guide sections in the intermediate portion from the incident surface to the end surface.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle lamps having a light guide that guides light by a plurality of light guide portions.

Background Art

[0002] Some vehicle lamps are configured such that a light source that emits light and a light guide having a plurality of light guide portions that guide the light emitted from the light source are disposed inside a lamp outer casing constituted by a cover and a lamp housing, and the light is controlled (reflected) by control steps and then emitted (see, for example, Patent Document 1).

[0003] In the vehicle lamp described in Patent Document 1, a plurality of columnar light guide portions are provided in a state of being arranged in the vertical direction, the light guide is formed in a long shape, one end in the longitudinal direction of the light guide portion is formed as an incident surface, and the light incident on the light guide portion from the incident surface is guided in the longitudinal direction and emitted from each light guide portion.

[0004] In the vehicle lamp described in Patent Document 1, light is emitted from each of the plurality of light guide portions provided in a parallel state, so that a linear light emission state is obtained, and the light is emitted in a state where the light overlaps at the boundary portions of the respective light guide portions. Therefore, even in a configuration in which a plurality of columnar light guide portions are provided, a surface light emission state is obtained, and a light emission state having good visibility is ensured.

Prior Art Documents

Patent Documents

[0007] Therefore, by configuring the light source to be incident from both sides in the longitudinal direction, it becomes possible to ensure uniformity of light. However, in this case, it becomes necessary to place light sources and substrates on which the light sources are mounted on both sides in the longitudinal direction, which increases the number of light sources and substrates and raises the manufacturing cost of vehicle lighting fixtures.

[0008] Therefore, the vehicle lighting fixture of the present invention aims to ensure uniformity of light without causing a surge in manufacturing costs. [Means for solving the problem]

[0009] The vehicle lighting device according to the present invention comprises a light source that emits light, and a light guide body having a plurality of light guides, one end face in the longitudinal direction formed as an incident surface and the other end face in the longitudinal direction formed as an end surface, which guides the light emitted from the light source from the incident surface to the end surface. The light guide body has a reflection step that internally reflects the guided light and an emission surface that emits the light reflected by the reflection step. The plurality of light guides are composed of at least one reference light guide extending from the incident surface to the end surface and a plurality of merging light guides that merge with other light guides in the intermediate portion from the incident surface to the end surface.

[0010] As a result, the number of light guides decreases as you move from the incident surface to the end surface, reducing the amount of light guiding, and light incident from the incident surface formed on one end surface in the longitudinal direction converges and is guided toward the end surface. [Effects of the Invention]

[0011] According to the present invention, the number of light guides decreases as you move from the incident surface to the end surface, reducing the amount of light guiding. At the same time, light incident from the incident surface formed on one end surface in the longitudinal direction converges and is guided toward the end surface. As a result, the amount of light per unit area emitted from the exit surface does not change easily in the longitudinal direction, and uniformity of light can be ensured without increasing manufacturing costs. [Brief explanation of the drawing]

[0012] [Figure 1] Figures 2 to 9 illustrate embodiments of the vehicle lighting device of the present invention, and this figure is a cross-sectional view of the vehicle lighting device. [Figure 2] This is a perspective view of the light guide. [Figure 3] This is a perspective view of the light guide, shown from a different direction than Figure 2. [Figure 4] This is an enlarged perspective view showing the incident side of the light guide. [Figure 5] This is an enlarged perspective view showing the middle portion of the light guide in the longitudinal direction. [Figure 6] This is an enlarged perspective view showing the end face portion of the light guide. [Figure 7] This is a cross-sectional view showing the light guide being held by the first holder and the second holder. [Figure 8] This is a side view showing the arrangement of the light sources. [Figure 9] This is a conceptual diagram showing the size of the light guide and its visible area. [Modes for carrying out the invention]

[0013] The embodiments for implementing the vehicle lighting device of the present invention will be described below with reference to the attached drawings.

[0014] The following describes the directions of light emission from a vehicle's lighting fixture, with the direction of light emission being forward, and the directions of forward, backward, up, down, left, and right being described. However, the directions of forward, backward, up, down, left, and right shown below are for the convenience of explanation, and the invention is not limited to these directions.

[0015] The vehicle lamp 1 functions as, for example, a daytime running lamp and a clearance lamp. However, the vehicle lamp 1 is not limited to a daytime running lamp and a clearance lamp, and may be other types of lamps attached to the front or rear side of the vehicle body.

[0016] The vehicle lamp 1 includes a lamp housing 2 having an opening at the front end and a cover 3 closing the opening of the lamp housing 2 (see FIG. 1). The vehicle lamp 1 is formed in a horizontally long shape, and both the lamp housing 2 and the cover 3 are formed in a horizontally long shape. The lamp housing 2 and the cover 3 constitute a lamp outer housing 4, and an internal space of the lamp outer housing 4 is formed as a lamp chamber 5.

[0017] An inner lens 6, a light guide 7, a first holder 8, and a second holder 9 are arranged in the lamp chamber 5. The inner lens 6, the light guide 7, the first holder 8, and the second holder 9 are all formed in a horizontally long shape, and the longitudinal direction is in the left - right direction. In addition, other members such as an extension may be arranged in the lamp chamber 5 in addition to the inner lens 6, the light guide 7, the first holder 8, and the second holder 9.

[0018] The inner lens 6 has a function of diffusing light. For example, a cylindrical step (not shown) is formed on the front surface of the inner lens 6. The light is diffused in the vertical and horizontal directions by the cylindrical step of the inner lens 6.

[0019] The light guide 7 is formed in a long shape extending in the left - right direction, and has a light emitting portion 10 extending in the left - right direction and two attachment portions 11 protruding from both ends in the longitudinal direction of the light emitting portion 10, and each part is integrally formed (see FIGS. 2 to 5). In addition, at least a part of the light guide 7 may be formed in a curved shape.

[0020] The light guide 7 has one end face in the longitudinal direction formed as the incident surface 12, and the other end face in the longitudinal direction formed as the end surface 13. The vertical width of the incident surface 12 is larger than the vertical width of the end surface 13.

[0021] The end of the light guide 7 on the terminal surface 13 side in the longitudinal direction is provided as a curved portion 7a that curves towards the rear, so that the terminal surface 13 faces backward. The end of the light guide 7 on the incident surface 12 side is located on the outside in the left-right direction of the vehicle, and the curved portion 7a is located on the center side in the left-right direction of the vehicle.

[0022] The light-emitting section 10 is formed in a shape in which its vertical width changes along its longitudinal direction. The light-emitting section 10 is provided with a plurality of light guide sections 14 extending in the longitudinal direction. The light guide sections 14 are formed in a substantially cylindrical shape extending substantially in the left-right direction and are arranged vertically. Therefore, the arrangement of the plurality of light guide sections 14 is in the vertical direction. For example, nine light guide sections 14 are provided. However, the number of light guide sections 14 is not limited to nine; any number is acceptable.

[0023] The light guide portion 14 has a diffusion step (not shown) on its front surface and a reflection step 15 on its rear surface. The diffusion step and reflection step 15 are formed on the portion of the light guide body 7 excluding both ends in the longitudinal direction. The front surface of the light guide portion 14 is formed as an emission surface 16 for emitting light. It is also possible to configure the light guide body 7 such that the diffusion step and reflection step 15 are not formed on the light guide portion 14 located at the bottom.

[0024] Of the nine light guide sections 14, for example, all but two light guide sections 14 merge with the other light guide sections 14 in the intermediate portion from the incident surface 12 to the end surface 13 (see Figures 4 to 6).

[0025] The light guide sections 14 that are not joined to the other light guide sections 14 are provided as a first reference light guide section 14P1 and a second reference light guide section 14P2, and both the first reference light guide section 14P1 and the second reference light guide section 14P2 are formed from the incident surface 12 to the end surface 13. Therefore, the incident surface 12 is a surface formed by the convergence of one end surface in the longitudinal direction of the nine light guide sections 14, and the end surface 13 is a surface formed by the convergence of the other end surfaces in the longitudinal direction of the first reference light guide section 14P1 and the second reference light guide section 14P2. One end surface in the longitudinal direction of the light guide section 14 is formed as a first surface 12a, and the other end surface in the longitudinal direction of the light guide section 14 is formed as a second surface 12b. The incident surface 12 is a surface formed by the convergence of the nine first surfaces 12a, and the end surface 13 is a surface formed by the convergence of the two second surfaces 13a.

[0026] The light guides 14 other than the first reference light guide 14P1 and the second reference light guide 14P2 are provided as merging light guides 14Q that merge with the other light guides 14. Therefore, the light guide body 7 is provided with, for example, seven merging light guides 14Q.

[0027] The first reference light guide section 14P1 is, for example, the uppermost light guide section 14, and the second reference light guide section 14P2 is, for example, the fifth light guide section 14 from the top. Therefore, the first reference light guide section 14P1 is provided in the position closest to one end 10a. The confluence light guide section 14Q consists of the second to fourth and sixth to ninth light guide sections 14 from the top.

[0028] Furthermore, the light guide body 7 only needs to have at least one reference light guide section, may have only one reference light guide section, or may have three or more reference light guide sections. Also, the vertical position of the reference light guide section is arbitrary; for example, it may be located at the position closest to the other end 10b, or it may be located at any of the 2nd to 8th positions from the top.

[0029] In the following, the light guide sections 14 located in the 2nd to 4th positions from the top and the 6th to 9th positions from the top may be referred to as confluence light guide section 14Q2, confluence light guide section 14Q3, confluence light guide section 14Q4, confluence light guide section 14Q6, confluence light guide section 14Q7, confluence light guide section 14Q8, and confluence light guide section 14Q9, respectively, for convenience.

[0030] In the four upper light guide sections 14 of the light guide body 7, starting from the incident surface 12 side, the converging light guide section 14Q2 merges with the first reference light guide section 14P1, the converging light guide section 14Q3 merges with the first reference light guide section 14P1, and the converging light guide section 14Q4 merges with the first reference light guide section 14P1. In addition, in the five lower light guide sections 14 of the light guide body 7, starting from the incident surface 12 side, the converging light guide section 14Q9 merges with the converging light guide section 14Q8, the converging light guide section 14Q6 merges with the second reference light guide section 14P2, the converging light guide section 14Q7 merges with the second reference light guide section 14P2, and the converging light guide section 14Q8 merges with the second reference light guide section 14P2.

[0031] Therefore, at the end on the incident surface 12 side, nine light guide sections 14 are arranged in a continuous vertical configuration, and at the end on the terminal surface 13 side, two light guide sections 14 are arranged in a continuous vertical configuration. Furthermore, as described above, when the converging light guide section 14Q is merged with the other light guide sections 14, the reflection steps 15 formed in the converging light guide section 14Q are also merged with the reflection steps 15 of the other light guide sections 14.

[0032] Furthermore, the above-described merging state in the light guide 7 is just one example, and other merging states are also possible.

[0033] As the light guide portion 14 is joined in the light guide body 7 as described above, the light guide body 7 is formed such that, excluding the mounting portion 11, the vertical width of the incident surface 12 is the largest and the vertical width of the end surface 13 is the smallest, and the vertical width decreases from the incident surface 12 to the end surface 13.

[0034] The first holder 8 and the second holder 9 have the function of holding the light guide 7. However, the first holder 8 and the second holder 9 may also function as reflectors that reflect light, including leaked light, emitted from the light guide 7. The second holder 9 also functions as a shielding member that shields a part of the light guide section 14.

[0035] The first holder 8 is positioned to extend from the upper side to the rear side of the light guide 7, covering the portion of the light guide 7 from the upper side to the rear side (see Figures 1 and 7). The upper end of the front end of the first holder 8 is provided as a holding portion 8a, which is formed in the shape of an arcuate surface that opens approximately forward. The first holder 8 is positioned so that the holding portion 8a covers the upper surface of the light emitting portion 10.

[0036] The second holder 9 is positioned below the light guide 7 and covers the lower surface of the light guide 7. The front end of the second holder 9 is provided as a holding portion 9a, which is formed in the shape of an arcuate surface that opens upward. The second holder 9 is positioned so that the holding portion 9a covers the lower end portion 10c of the light emitting portion 10. The lower end portion 10c of the light emitting portion 10 is part of the light guide 14 located at the very bottom and is shielded by the holding portion 9a, making it invisible from the front.

[0037] The first holder 8 and the second holder 9 are attached to the lamp housing 2, for example, by screws. The two mounting parts 11 of the light guide 7 are attached to the first holder 8 by screws.

[0038] Multiple light sources 17 are positioned opposite the incident surface 12 of the light guide 7 (see Figure 8). Light-emitting diodes (LEDs) are used as the light sources 17.

[0039] Multiple light sources 17 are mounted on a substrate (not shown) in a roughly vertical arrangement, positioned towards one end 10a (upper end) of the light guide section 14 and not positioned near the other end 10b. Light emitted from the light sources 17 enters the light emission section 10 from the incident surface 12 and is guided towards the end surface 13 in the light guide section 14.

[0040] In the light guide 7, the first reference light guide section 14P1 and the second reference light guide section 14P2 are located in the 1st and 5th positions from the top, respectively, and at the end surface 13, all the converging light guide sections 14Q ultimately merge with the first reference light guide section 14P1 and the second reference light guide section 14P2, which are located in the 1st and 5th positions from the top.

[0041] Therefore, by arranging the multiple light sources 17 so that they are positioned towards one end 10a, the multiple light sources 17 are positioned towards the first reference light guide 14P1 and the second reference light guide 14P2. As a result, light emitted from the multiple light sources 17 is less likely to leak from the light guide 14, and the light emitted from the light sources 17 can be effectively utilized.

[0042] With the first holder 8 and the second holder 9 attached to the lamp housing 2 and the light guide 7 attached to the first holder 8, the portions of the light guide 7 at both ends in the longitudinal direction are covered from the front by, for example, the first holder 8 or an extension. Therefore, the two attached portions 11 of the light guide 7, the substrate, and the multiple light sources 17 are shielded from the front. The first holder 8 and the second holder 9 may also be shielded from the front by an extension.

[0043] In the vehicle lighting fixture 1 configured as described above, when light is emitted from the light source 17, the emitted light enters each light guide portion 14 of the light guide body 7 from the incident surface 12, is guided longitudinally in the light guide portion 14, undergoes internal reflection (total internal reflection) by the reflection step 15, and is emitted from the emission surface 16. The light emitted from the emission surface 16 is sequentially transmitted through the inner lens 6 and the cover 3 and irradiated outwards. When light is emitted from the emission surface 16, the light is diffused vertically and horizontally by the cylindrical step formed on the front surface of the light guide portion 14. Furthermore, when the light emitted from the emission surface 16 is transmitted through the inner lens 6, it is further diffused by the inner lens 6, and the diffused light is transmitted through the cover 3 and irradiated outwards.

[0044] As described above, when light incident from the incident surface 12 is guided by the light guide section 14, the amount of light attenuation increases with the distance the light is guided from the incident surface 12. However, in the light guide body 7, the converging light guide section 14Q merges with other light guide sections 14, so the amount of light guided decreases as it approaches the end surface 13 from the incident surface 12. Therefore, because the light is also merged when the light guide sections 14 merge, even if attenuation occurs in each light guide section 14, the amount of light per unit area emitted from the emission surface 16 does not change easily in the longitudinal direction, and the light is more likely to be emitted in a uniform state along the longitudinal direction of the light guide body 7.

[0045] In the light guide 7, light is emitted from the emission surface 16 of each light guide section 14, but as described above, the lower end 10c of the light emission section 10 is shielded from the front by the holding section 9a of the second holder 9. In addition, the left and right ends of the light guide 7 are shielded from the front by, for example, the first holder 8 or extension. Therefore, the visible area S of the light emission section 10 when viewed from the front is small relative to the front surface area (see Figure 9). The light guided by the light guide section 14 is emitted from the entire visible area S.

[0046] In this case, it is also possible to reduce the size of the light-emitting section 10 by not using the second holder 9 and not forming the lower end 10c of the light-emitting section 10, thereby making the front surface area of ​​the light-emitting section 10 the same as the vertical width of the visible area S. However, with such a configuration, the inclination angle of the lower end D with respect to the upper end U becomes excessively large, which reduces the propagation efficiency of the light incident from the incident surface 12 in the light-guiding direction, making light leakage more likely, and making it difficult for a sufficient amount of light to be emitted from the visible area S.

[0047] Therefore, as with the vehicle lighting fixture 1, by shielding the lower end portion 10c with the holding portion 9a of the second holder 9 without reducing the size of the light emitting portion 10, the propagation efficiency in the light guiding direction of the light incident from the incident surface 12 can be increased, thereby ensuring a good emission state from the visible area S.

[0048] Furthermore, in the vehicle lighting fixture 1, it is also possible to form the first holder 8 and the second holder 9 as a single integrated component. However, if forming the holding portion 8a and the holding portion 9a results in an undercut, it may be necessary to use a molding slider or the like during molding with a mold, potentially increasing manufacturing costs. Therefore, as described above, forming the first holder 8 and the second holder 9 as separate components makes it easier to form the first holder 8 and the second holder 9 without significantly increasing manufacturing costs.

[0049] As described above, the vehicle lighting device 1 includes a light guide body 7 having a plurality of light guide sections 14, one end surface in the longitudinal direction of which is formed as an incident surface 12, and which guides light from the incident surface 12 to the end surface 13. The plurality of light guide sections 14 are composed of at least one reference light guide section 14P and a plurality of merging light guide sections 14Q which merge with the other light guide sections 14.

[0050] Therefore, as the light guide portion decreases from the incident surface 12 towards the end surface 13, the number of light guide sections 14 decreases, and the light incident from the incident surface 12 formed on one end surface in the longitudinal direction converges and is guided toward the end surface 13. As a result, the amount of light per unit area emitted from the exit surface 16 does not change easily in the longitudinal direction of the light guide section 14, and uniformity of light can be ensured without increasing manufacturing costs.

[0051] Furthermore, since it is not necessary to place a substrate and a light source 17 at both ends in the longitudinal direction of the light guide 7, the space required for the substrate and light source 17 is reduced, making it possible to miniaturize the vehicle lighting fixture 1 while ensuring uniformity of light.

[0052] Furthermore, since the number of light guides 14 is increased in the light guide 7, if the vertical width of the light emitting section 10 is the same, the greater the number of light guides 14, the shallower the groove 14a formed between adjacent light guides 14 becomes (see Figure 8).

[0053] Therefore, the amount of light emitted from the portion where the groove 14a is formed does not decrease drastically, and the portion of the groove 14a is not easily visible as a black streak when light is emitted, thus ensuring a good light emission state in the light guide 7.

[0054] Furthermore, the number of light guide portions 14 of the light guide body 7 is preferably four or more, and may be any number from four to eight, or even ten or more.

[0055] Furthermore, the reference light guide section 14P is positioned closest to one end 10a in the direction of alignment of the light guide sections 14.

[0056] Therefore, since the confluence light guide section 14Q merges with the reference light guide section 14P only from the other side in the alignment direction, the width of the light-emitting region can be changed in the longitudinal direction while simplifying the design.

[0057] Furthermore, since the end of the light guide 7 on the terminal surface 13 side is provided as a curved portion 7a, the end on the side to which the light is guided has a curved shape, making it less likely for a point light state with extremely high brightness to occur at the end on the side to which the light is guided, and thus improving the uniformity of the light emitted from the light guide 7.

[0058] Although the curved section 7a is shielded from the front by the first holder 8 and extension as described above, if a point of light occurs, high-luminosity light may leak out from the gap between the first holder 8 and extension and the curved section 7a. Therefore, preventing point of light from occurring in the curved section 7a is highly effective in improving the uniformity of the light emitted from the light guide 7.

[0059] Furthermore, since the mounting portion 11 protrudes from the curved portion 7a provided as the end on the terminal surface 13 side, the mounting portion 11 is located at the end in the longitudinal direction of the light guide 7, and the light guide 7 can be attached to a predetermined member, for example, the first holder 8, while reducing the space required for the arrangement of the light guide 7 in the longitudinal direction. [Explanation of Symbols]

[0060] 1. Vehicle lighting fixtures 7 Light guide 7a Curved section 9. Second holder (shielding member) 10a one end 10b Other end 11 Mounted part 12 Incidence plane 13 End surface 14 Light guide section 14P1 First reference light guide 14P2 Second reference light guide section 14Q Merging light guide section 15 Reflection Step 16. Ejection surface 17 Light source

Claims

1. A light source that emits light, The light guide comprises a light guide body having one end face in the longitudinal direction formed as an incident surface and the other end face in the longitudinal direction formed as an end surface, and having a plurality of light guide portions that guide light emitted from the light source from the incident surface to the end surface, The light guide has a reflection step that internally reflects the guided light and an emission surface that emits the light reflected by the reflection step. The plurality of light guides are composed of at least one reference light guide extending from the incident surface to the end surface and a plurality of converging light guides that merge with other light guides in the intermediate portion from the incident surface to the end surface. Vehicle lighting fixtures.

2. The reference light guide is provided at the position closest to one end in the direction in which the multiple light guides are aligned. A vehicle light fixture according to claim 1.

3. A shielding member is provided to shield a portion of the light guide portion located at the position closest to the other end in the direction in which the multiple light guide portions are aligned. The vehicle lighting fixture according to claim 2.

4. Multiple of the aforementioned light sources are arranged in a line facing the incident surface, Multiple light sources are arranged so as to be concentrated towards one end in the direction of alignment of the light guide section. A vehicle light fixture according to claim 2 or claim 3.

5. The end portion of the light guide on the terminal side is provided as a curved portion. A vehicle light fixture according to claim 1, claim 2, or claim 3.

6. The light guide has a mounting portion protruding from the end on the terminal side, which is attached to a predetermined member. A vehicle light fixture according to claim 5.

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