Vehicular lighting fixture

Abstract

To provide a vehicular lighting fixture which enables more uniform light emission, while preventing increase in the number of components.SOLUTION: A vehicular lighting fixture includes a light source 2, and a light guide body 3. The light guide body 3 includes: a first lens part 10 including a first incident part 8 positioned on the side opposing to the light source 2, and a first emission part 9 positioned on the opposite side from the first incident part 8; a second lens part 13 including a second incident part 11 positioned on the side opposing to the first lens part 10 and a second emission part 12 positioned on the opposite side from the second incident part 11; and a connection part 14 for connecting between the first lens part 10 and the second lens part 13, while forming a space K between the first emission part 9 and the second incident part 11. The first emission part 9 causes diffusing light L which has entered from the first incident part 8 to emit the outside of the first lens part 10 while the diffusing the light L by a plurality of first diffusion cuts 15, and the second incident part 11 causes the light L emitted from the first emission part 9 to enter the inside of the second lens part 13, while diffusing the light L by a plurality of second diffusion cuts 16.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a vehicle lamp. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a combination of a light source such as a light emitting diode (LED) and a light guide such as an inner lens has been known as a vehicle lamp to be mounted on a vehicle (see, for example, Patent Document 1 below).

[0003] In such vehicle lamps, light emitted from a light source enters the light guide from the back side and exits from the front side of the light guide, causing the front side of the light guide to emit light as the light-emitting surface of the vehicle lamp. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-112037 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional vehicle lamps described above, a portion corresponding to the light source shines brighter than other portions, which is called point light, making it difficult to uniformly illuminate the light-emitting surface of the light guide.

[0006] Therefore, in conventional vehicle lamps, a diffusion section is provided on the light guide, and the light emitted from the light guide is diffused by the diffusion section, while the light emitting surface of the light guide is made to emit light uniformly. For example, the above-mentioned Patent Document 1 discloses a configuration in which collimating sections and flute cuts are provided on two inner lenses to diffuse light.

[0007] However, when using multiple light guides each having such a diffusion portion to diffuse light multiple times, a number of light guides are required, resulting in an increase in the number of parts and an increase in the assembly labor.

[0008] The present invention has been proposed in view of the above-mentioned conventional circumstances, and has an object to provide a vehicle lamp that is capable of emitting more uniform light while preventing an increase in the number of parts. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention provides the following means. [1] A light source; a light guide that guides the light emitted from the light source, The light guide includes a first lens portion including a first incident portion located on a side facing the light source and a first exit portion located on an opposite side to the first incident portion; a second lens unit including a second entrance portion located on a side facing the first lens unit and a second exit portion located on an opposite side to the second entrance portion; a connecting portion that connects the first lens portion and the second lens portion while forming a space between the first emission portion and the second incidence portion, the first exit portion includes a plurality of first diffusion cuts, and emits light incident from the first entrance portion to an outside of the first lens portion while diffusing the light by the plurality of first diffusion cuts; The second entrance portion includes a plurality of second diffusion cuts, and the light emitted from the first exit portion is diffused by the plurality of second diffusion cuts while entering the inside of the second lens portion. [2] The vehicular lamp according to [1], wherein the distance between the first emission portion and the second incidence portion gradually increases toward an opposite side to the connecting portion. [3] The vehicle lamp according to [1], wherein the first diffusion cut and the second diffusion cut diffuse light in a horizontal direction of the light guide. [4] The vehicle lamp according to [1], wherein the first diffusion cut has a smaller degree of diffusion than the second diffusion cut. [5] The vehicular lamp according to [1], wherein the first incident portion has a lens shape that condenses light emitted from the light source and causes the light to enter the inside of the first lens portion. [6] The vehicle lamp according to [1], wherein the second exit portion includes a plurality of third diffusion cuts, and the light incident from the second entrance portion is diffused by the plurality of third diffusion cuts while being emitted to the outside of the second lens portion. [7] The vehicular lamp according to [6], wherein the third diffusion cut diffuses light in a horizontal direction and a vertical direction of the light guide. Effect of the Invention

[0010] As described above, according to the present invention, a vehicle lamp capable of emitting more uniform light while preventing an increase in the number of parts is provided. [Brief description of the drawings]

[0011] [Figure 1] 1 is a front view showing a vehicle lamp according to an embodiment of the present invention; [Diagram 2] 2 is a cross-sectional view of the vehicular lamp taken along line AA shown in FIG. 1. [Diagram 3] 2 is a cross-sectional view of the vehicular lamp taken along line BB shown in FIG. 1. [Figure 4] FIG. 2 is a front view showing a circuit board on which a plurality of light sources are mounted. [Diagram 5] FIG. 2 is a perspective view showing an inner lens. [Figure 6] FIG. 2 is a front view showing the inner lens. [Figure 7] 7 is a cross-sectional view of the inner lens taken along line CC shown in FIG. 6. [Figure 8] 7 is a cross-sectional view of the inner lens taken along line DD shown in FIG. 6. [Figure 9] 2 is a cross-sectional view showing the optical path of light emitted from a light source of a vehicle lamp. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings used in the following description, in order to make each component easier to see, the dimensions of the components may be shown at different scales, and the dimensional ratios of each component may not necessarily be the same as in reality.

[0013] As an embodiment of the present invention, for example, a vehicle lamp 1 shown in Figs. 1 to 9 will be described. FIG. 1 is a front view showing the vehicle lamp 1. FIG. 2 is a cross-sectional view of the vehicle lamp 1 taken along line AA shown in FIG. 1. FIG. 3 is a cross-sectional view of the vehicle lamp 1 taken along line BB shown in FIG. 1. FIG. 4 is a front view showing a circuit board 7 on which a plurality of light sources 2 are mounted. FIG. 5 is a perspective view showing the inner lens 3. FIG. 6 is a front view showing the inner lens 3. FIG. 7 is a cross-sectional view of the inner lens 3 taken along line CC shown in FIG. 6. FIG. 8 is a cross-sectional view of the inner lens 3 taken along line DD shown in FIG. 6. FIG. 9 is a cross-sectional view showing the optical path of light L emitted from the light source 2 of the vehicle lamp 1.

[0014] In addition, in the drawings shown below, an XYZ Cartesian coordinate system is set up, with the X-axis direction representing the front-to-rear direction (length direction) of the vehicle lighting fixture 1, the Y-axis direction representing the left-to-right direction (width direction) of the vehicle lighting fixture 1, and the Z-axis direction representing the up-down direction (height direction) of the vehicle lighting fixture 1.

[0015] The vehicle lamp 1 of this embodiment is, for example, as shown in FIG. 1, an application of the present invention to a back lamp BCL that emits white light in a circular shape, among rear combination lamps RCL mounted on both corners of the rear end of a vehicle (not shown) (in this embodiment, the corner on the right rear end).

[0016] Among the rear combination lamps RCL, the tail lamp / stop lamp TLL / STL that emits red light in a circular ring shape is arranged outside the back lamp BCL. Also, the turn wrap TRL that emits orange light in a substantially rectangular shape is arranged outside the tail lamp / stop lamp TLL / STL in the vehicle width direction.

[0017] As shown in Figures 1, 2 and 3, the vehicle lamp 1 of this embodiment has at least one or more (two in this embodiment) light sources 2 and an inner lens 3, which are arranged inside the lamp body 4.

[0018] The lamp body 4 is composed of a housing 5 with an opening at the front and a transparent outer lens 6 that covers the opening of the housing 5.

[0019] In addition, in the vehicle lamp 1 of this embodiment, the front side of the lamp body 4 (outer lens 6) is shaped so that the outer side is set back more than the inner side in the vehicle width direction in accordance with the slanted shape given to the corner portion at the rear end of the vehicle.

[0020] 2, 3 and 4, the light source 2 is, for example, an LED that emits white light (hereinafter referred to as "light") L. Two light sources 2 are mounted (arranged) side by side in the vertical direction (up and down direction) in the center of the front side of a substantially circular circuit board 7 on which a drive circuit (not shown) that drives the LEDs is provided.

[0021] As a result, each light source 2 radially emits light L toward the front inner lens 3. That is, these two light sources 2 are provided on the same surface of the same circuit board 7, and emit light L in the same direction.

[0022] In this embodiment, the LEDs constituting the light source 2 described above and the drive circuit for driving the LEDs are mounted on a circuit board 7, but the present invention is not necessarily limited to this configuration.

[0023] For example, a mounting board on which the LEDs are mounted and a circuit board on which a drive circuit for driving the LEDs is provided may be arranged separately, and the mounting board and the circuit board may be electrically connected via a wiring cord called a harness to protect the drive circuit from heat generated by the LEDs.

[0024] As shown in FIGS. 2, 3, and 5 to 8, the inner lens 3 is made of a transparent resin such as polycarbonate (PC) or acrylic (PMMA).

[0025] The inner lens 3 serves as a light guide and is disposed in front of the light source 2 to guide the light L emitted from the light source 2.

[0026] Specifically, this inner lens 3 has a first lens portion 10 including a first entrance portion 8 located on the side facing the light source 2 and a first exit portion 9 located on the opposite side to the first entrance portion 8, a second lens portion 13 including a second entrance portion 11 located on the side facing the first lens portion 10 and a second exit portion 12 located on the opposite side to the second entrance portion 11, and a connecting portion 14 that connects the first lens portion 10 and the second lens portion 13 while forming a space K between the first exit portion 9 and the second entrance portion 11.

[0027] Furthermore, connecting portion 14 is formed in a substantially semicylindrical shape and connects the outer periphery on the upper side between first lens portion 10 and second lens portion 13. As a result, first emission portion 9 and second incidence portion 11 are inclined and face each other with space K surrounded by first lens portion 10, second lens portion 13, and connecting portion 14 in between.

[0028] The inner lens 3 is formed by injection molding using a mold. In addition, the distance between the first emission part 9 and the second incidence part 11 of the inner lens 3 gradually increases in the direction in which the inner lens 3 is removed from the mold after molding, i.e., toward the opposite side to the connecting part 14. This allows the inner lens 3 to be removed from the mold during molding, and can be manufactured inexpensively by removing the inner lens 3 from the mold in one go.

[0029] The two first entrance portions 8 are arranged vertically side by side in the center of the rear surface side of the inner lens 3 so as to face the two light sources 2, one above the other.

[0030] The first incident portion 8 has a lens shape that causes the light L emitted from the light source 2 to enter the inside of the inner lens 3 while collecting the light L toward the optical axis.

[0031] Specifically, this first incident portion 8 has a first light-collecting incident surface 8a located at the center of the portion facing the light source 2 and on which a portion of the light L emitted from the light source 2 is incident, a second light-collecting incident surface 8b located on the inner side of a protrusion that protrudes toward the light source 2 from a position surrounding the first light-collecting incident surface 8a and on which a portion of the light L emitted from the light source 2 is incident, and a light-collecting reflecting surface 8c located on the outer side of the protrusion and reflecting the light L incident from the second light-collecting incident surface 8b.

[0032] In the first incident portion 8, the light L radially emitted from the light source 2 and incident into the inside of the inner lens 3 from the first light-collecting incident surface 8a is collected toward the optical axis. On the other hand, the light L incident into the inside of the inner lens 3 from the second light-collecting incident surface 8b is reflected by the light-collecting reflecting surface 8c, thereby being collected toward the optical axis.

[0033] As a result, first incident portion 8 collimates light L radially emitted from light source 2, and causes the light L to enter the inside of first lens unit 10. Furthermore, light L that enters the inside of first lens unit 10 from first incident portion 8 is guided toward the front side of first lens unit 10.

[0034] The first emission section 9 has a plurality of first diffusion cuts 15 on the front side of the first lens section 10. In this embodiment, the first diffusion cuts 15 are configured by a plurality of flute cuts arranged in the horizontal direction (left-right direction) and having grooves with a generally arc-shaped cross section that cut out the front side of the first lens section 10 in the vertical direction (up-down direction).

[0035] As a result, in first exit portion 9, light L incident from first entrance portion 8 is diffused in the horizontal direction (left-right direction) by multiple first diffusion cuts 15, and is emitted to space K outside first lens portion .

[0036] Second entrance portion 11 has a plurality of second diffusion cuts 16 on the front side of second lens portion 13. In this embodiment, second diffusion cuts 16 are configured by a plurality of flute cuts arranged horizontally (left-right) in the rear side of second lens portion 13, the flute cuts having grooves with a generally arc-shaped cross section that cut out the rear side of second lens portion 13 in the vertical direction (up-down direction).

[0037] As a result, in second incident portion 11, light L emitted from first incident portion 9 to space K is diffused in the horizontal direction (left-right direction) by multiple second diffusion cuts 16 and enters the inside of second lens portion 13. In addition, light L that enters the inside of second lens portion 13 from second incident portion 11 is guided toward the front side of second lens portion 13.

[0038] The second exit section 12 has a plurality of third diffusion cuts 17 on the back side of the second lens section 13. In this embodiment, the third diffusion cuts 17 are configured as Fresnel-shaped fisheye cuts. In the second exit section 12, by adjusting the shape of the third diffusion cuts 17, it is possible to control the degree of diffusion and light distribution of the light L exiting from the second exit section 12.

[0039] As a result, in the second exit section 12, the light L incident from the second entrance section 11 is diffused horizontally (left-right) and vertically (up-down) by multiple third diffusion cuts 17, and is emitted to the outside of the second lens section 13.

[0040] In the vehicle lamp 1 of this embodiment having the above-mentioned configuration, it is possible to emit white light in a circular shape from the front side of the second lens portion 13 (the inner lens 3), which serves as the light emitting surface of the above-mentioned back lamp BCL.

[0041] The vehicle lamp 1 of this embodiment has a structure in which the first lens portion 10 and the second lens portion 13 are connected via the above-mentioned connecting portion 14. This makes it possible to prevent an increase in the number of parts and an increase in the number of assembly steps.

[0042] Furthermore, in the vehicle lamp 1 of this embodiment, by adjusting the degree of diffusion between the multiple first diffusion cuts 15 provided in the first exit portion 9 and the multiple second diffusion cuts 16 provided in the second entrance portion 11, it is possible to make the light-emitting surface of the back lamp BCL emit light more uniformly.

[0043] Specifically, in the vehicle lamp 1 of this embodiment, the degree of diffusion of the light L by the plurality of first diffusion cuts 15 is smaller than the degree of diffusion of the light L by the plurality of second diffusion cuts 16.

[0044] Further, the degree of diffusion of light L by the plurality of first diffusion cuts 15 is set so that light L emitted from first exit portion 9 enters the effective lens range of second entrance portion 11.

[0045] On the other hand, the degree of diffusion of the light L by the plurality of second diffusion cuts 16 is set so as to eliminate uneven luminance (light emission) in which the portion corresponding to the light source 2 shines brighter than other portions.

[0046] This allows the light emitting surface of the back lamp BCL to emit light more uniformly, improving the appearance when illuminated.

[0047] The present invention is not necessarily limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0048] For example, in the above embodiment, the back lamp BCL of the above-mentioned rear combination lamp RCL emits white light, but the present invention can be applied to other vehicle lamps. Also, the present invention can be applied not only to the above-mentioned rear vehicle lamps, but also to front vehicle lamps.

[0049] In other words, in terms of vehicular lighting fixtures to which the present invention can be applied, in addition to the above-mentioned backup lamps, tail lamps, stop lamps, and turn lamps, the present invention can be widely applied to vehicular lighting fixtures such as daytime running lamps (DRLs) and position lamps.

[0050] In addition, the color of the light emitted by the light source can be changed as appropriate depending on the application of the vehicle lamp, such as the above-mentioned red light, orange light, or white light. [Explanation of symbols]

[0051] REFERENCE SIGNS LIST 1...vehicle lamp 2...light source 3...inner lens (light guide) 4...lamp body 5...housing 6...outer lens 7...circuit board 8...first entrance portion 9...first exit portion 10...first lens portion 11...second entrance portion 12...second exit portion 13...second lens portion 14...connecting portion 15...first diffusion cut 16...second diffusion cut 17...third diffusion cut

Claims

1. A light source; a light guide that guides the light emitted from the light source, The light guide includes a first lens portion including a first incident portion located on a side facing the light source and a first exit portion located on an opposite side to the first incident portion; a second lens unit including a second entrance portion located on a side facing the first lens unit and a second exit portion located on an opposite side to the second entrance portion; a connecting portion that connects the first lens portion and the second lens portion while forming a space between the first emission portion and the second incidence portion, The first exit portion includes a plurality of first diffusion cuts, and the light incident from the first entrance portion is diffused by the plurality of first diffusion cuts and is emitted to the outside of the first lens portion. The second entrance portion includes a plurality of second diffusion cuts, and the light emitted from the first exit portion is diffused by the plurality of second diffusion cuts while entering the inside of the second lens portion.

2. The vehicular lamp according to claim 1 , wherein a distance between the first emission portion and the second incidence portion gradually increases toward an opposite side to the connecting portion.

3. The vehicle lamp according to claim 1 , wherein the first diffusion cut and the second diffusion cut diffuse light in a horizontal direction of the light guide.

4. The vehicle lamp according to claim 1 , wherein the first diffusion cut has a smaller degree of diffusion than the second diffusion cut.

5. The vehicular lamp according to claim 1 , wherein the first incident portion has a lens shape that condenses the light emitted from the light source and causes the light to enter the inside of the first lens portion.

6. 2. The vehicular lamp according to claim 1, wherein the second exit portion includes a plurality of third diffusion cuts, and the light incident from the second entrance portion is diffused by the plurality of third diffusion cuts while being emitted to an outside of the second lens portion.

7. The vehicle lamp according to claim 6 , wherein the third diffusion cut diffuses light in a horizontal direction and a vertical direction of the light guide.

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