JP2014099324A - Lamp for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lamp for a vehicle using a light guide with high utilization efficiency of light from a light source.SOLUTION: A lamp for a vehicle comprises: a light source 21; and a light guide 30 having an incident part 31 on which light from the light source 21 is incident, and plural extension parts branched and extending from the incident part 31 and emitting the light. Each of the plural extension parts includes: a first extension part 36 having a portion extending on an optical axis Ax of the light source 21; a second extension part 37 extending in a longitudinal direction of the first extension part 36, and parallely aligned on one side of the first extension part 36; and a third extension part 38 extending in the longitudinal direction of the first extension part 36, and parallely aligned on the other side of the first extension part 36. The incident part 31 has a first reflection part 32 for internally reflecting the incident light to the second extension part 37, and a second reflection part 33 for internally reflecting the incident light to the third extension part 38.

Description

  The present invention relates to a vehicular lamp.

  2. Description of the Related Art Conventionally, there is known a vehicular lamp having a configuration in which light is incident on a bar-shaped light guide branched from a LED light source into a plurality of (for example, two) light sources, and the entire light guide emits light. (See Patent Document 1).

JP 2003-68113 A

  In recent years, it has been required to increase the light use efficiency of such a light guide. However, in the vehicular lamp of Patent Document 1, light from a light source is simply incident from one end of the light guide and branched. Therefore, it cannot be said that the light use efficiency is good.

  Then, an object of this invention is to provide the vehicle lamp using the light guide with the high utilization efficiency of the light from a light source.

In order to achieve the above object, a vehicular lamp according to the present invention includes:
A light source;
A light guide having an incident portion on which light from the light source is incident, and a plurality of extending portions that branch out from the incident portion and emit the light;
With
The plurality of extending portions include a first extending portion having a portion extending on the optical axis of the light source, and the first extending portion extending along a longitudinal direction of the first extending portion. A second extension portion arranged in parallel with one side of the extension portion, and a third extension extended along the longitudinal direction of the first extension portion and arranged in parallel with the other side of the first extension portion And including
The incident portion includes a first reflecting portion that internally reflects the incident light toward the second extending portion, and a second reflection that internally reflects the incident light toward the third extending portion. And a portion.

According to the present invention, the incident portion is
A first incident portion disposed on the optical axis;
A second incident part that is disposed on one side of the first incident part and allows light from the light source to enter the first reflecting part;
A third incident part disposed on the other side of the first incident part and allowing light from the light source to enter the second reflecting part;
It is good also as a structure provided with.

  According to the present invention, the light guided inside the light guide body is each side surface portion along the longitudinal direction in the first extension portion, the second extension portion, and the third extension portion. It is good also as a structure radiate | emitted from.

  According to the present invention, the light guided inside the light guide body is each end portion facing the incident portion in the first extension portion, the second extension portion, and the third extension portion. It is good also as a structure radiate | emitted from.

According to the present invention, an inner lens is provided between the light source and the incident portion,
The inner lens may have a configuration in which light from the light source is condensed and incident on the incident portion in a direction orthogonal to a plane including the light source, the first reflecting portion, and the second reflecting portion.

  According to the present invention, the incident portion of the light guide includes the first reflecting portion that internally reflects the light from the light source toward the second extending portion, and the inner surface that reflects the light from the light source toward the third extending portion. Since it has the 2nd reflection part to reflect, it is unnecessary to provide a plurality of light sources according to the number of extension parts, and it is from the 1st to the 3rd extension part using a single light source. The three extending portions can be made to emit light substantially uniformly. Therefore, the light use efficiency can be increased.

It is a front view which shows the structure of the vehicle lamp which concerns on the 1st Embodiment of this invention. It is a block diagram of the light source and light guide with which the vehicle lamp shown by FIG. 1 is equipped. FIG. 3 is a partially enlarged view of the light source and the light guide shown in FIG. 2. FIG. 4 is a cross-sectional view taken along line AA of the light source and the light guide shown in FIG. 3. It is a block diagram of the light source and light guide which concern on the modification of 1st Embodiment. It is a block diagram of the light source and light guide which concern on the 2nd Embodiment of this invention.

  Hereinafter, an example of an embodiment of a vehicular lamp according to the present invention will be described with reference to the drawings.

(First embodiment)
As shown in FIG. 1, a vehicular lamp 10 according to a first embodiment of the present invention includes a resin lamp body 11 that is fixed to a vehicle body in a shape in which a front side of the vehicle is opened, and an opening of the lamp body 11. And an outer cover 12 made of a transparent resin attached to the portion. The outer cover 12 is disposed so as to close the opening of the lamp body 11 from the front, and forms a lamp chamber S between the outer cover 12 and the lamp body 11. The vehicular lamp 10 can be used as, for example, a vehicular tail lamp, and is particularly preferably used as a left tail lamp that is disposed on the left side when the vehicle is viewed from the rear. Therefore, in FIG. 1, the left side of the lamp body 11 is the left end side of the rear part of the vehicle, and the right side of the lamp body 11 is the central side of the rear part of the vehicle.

  The vehicular lamp 10 includes a lamp unit 20 in a lamp chamber S formed by a lamp body 11 and an outer cover 12. The lamp unit 20 includes a light source 21 and a light guide 30 that extends in the left-right direction.

  The light source 21 is composed of a red light emitting diode (LED) having a light emitting part with a size of about 1 mm square, for example. The light source 21 is disposed so as to face the right end portion of the light guide 30 through the support member 13 fixed to the right opening end of the lamp body 11. The light source 21 composed of LEDs emits light substantially uniformly in the vertical and horizontal directions toward the front of the lamp.

  As shown in FIG. 1, the light guide 30 is formed in an arc shape along the shape of the outer cover 12. As shown in FIG. 2, the light guide 30 is provided to face the emission surface of the light source 21 and is incident on the light incident from the light source 21. A plurality of extending portions 35.

  The plurality of extending portions 35 include a first extending portion 36 having a portion extending on the optical axis of the light source 21, and a second extending portion extending along the longitudinal direction of the first extending portion 36. Part 37 and a third extension part 38 extending along the longitudinal direction of the first extension part 36. As shown in FIG. 3, the first extending portion 36 of the present example is formed to extend in a plane including the optical axis Ax of the light source 21 and the horizontal line in the left-right direction. The second extending portion 37 is arranged in parallel with one side (the upper side in FIG. 2) of the first extending portion 36 in the vertical direction of the vehicular lamp 10. Further, the third extending portion 38 is arranged in parallel with the other side (the lower side in FIG. 2) of the first extending portion 36 in the vertical direction of the vehicular lamp 10. Each of the first to third extending portions 36 to 38 is formed to have, for example, a substantially circular shape in a cross section perpendicular to the longitudinal direction.

The incident portion 31 includes a first reflecting portion 32 that internally reflects light incident from the light source 21 toward the second extending portion 37, and an inner surface that reflects light incident from the light source 21 toward the third extending portion 38. It has the 2nd reflection part 33 to reflect.
As shown in FIG. 3, the incident part 31 is further disposed on the first incident part 31a disposed on the optical axis Ax of the light source 21 and on one side (the upper side in FIG. 3) of the first incident part 31a. The second incident part 31b that makes the light incident on the first reflecting part 32 and the second incident part 31a on the other side (the lower side in FIG. 3) of the first incident part 31a. A third incident portion 31c for incidence.

  The 1st incident part 31a is comprised from the substantially hemispherical surface. Therefore, at least a part of the light L1 emitted from the light source 21 and incident on the first incident portion 31a is first incident so as to approach a direction parallel to the optical axis Ax in the vertical direction of the vehicular lamp 10. The light is refracted by the portion 31 a and guided into the first extension portion 36. As shown in FIG. 4, the light L <b> 1 has an optical axis in the front-rear direction of the vehicular lamp 10, i.e., in the direction orthogonal to the plane including the light source 21, the first reflecting portion 32, and the second reflecting portion 33. The light is refracted by the first incident portion 31a so as to approach Ax. The term “refracted so as to approach the optical axis Ax” includes a configuration in which light is guided so as to be substantially parallel to the optical axis Ax, or is guided so as to be diffused after being condensed toward the focal point.

As shown in FIG. 3, the second incident portion 31 b is configured in a straight line when viewed from the front of the lamp (that is, in a cross section perpendicular to the front-rear direction). Therefore, the second incident portion 31b refracts at least a part of the light L2 of the light incident from the light source 21 to the second incident portion 31b in a direction away from the optical axis Ax in the vertical direction of the vehicular lamp 10.
Similarly to the first incident portion 31a shown in FIG. 4, the second incident portion 31b is formed in an arc shape when viewed from the left side of the lamp (that is, in a cross section perpendicular to the left-right direction). Therefore, the second incident portion 31b refracts the light L2 so as to approach a direction parallel to the optical axis Ax in the front-rear direction of the vehicular lamp 10. In this way, the second incident portion 31 b can make the light L <b> 2 incident toward the first reflecting portion 32.

Similarly to the second incident portion 31b, the third incident portion 31c is configured in a straight line when viewed from the front of the lamp (that is, in a cross section perpendicular to the front-rear direction). Therefore, the third incident portion 31c, for example, has an angle α in the direction away from the optical axis Ax in the vertical direction of the vehicular lamp 10 for at least part of the light incident on the third incident portion 31c from the light source 21. Only refract.
Similarly to the first incident part 31a shown in FIG. 4, the third incident part 31c is formed in an arc shape when viewed from the left side of the lamp (that is, in a cross section perpendicular to the left-right direction). For this reason, the third incident portion 31c refracts the light L3 so as to approach a direction parallel to the optical axis Ax in the front-rear direction of the vehicle lamp 10. In this way, the third incident portion 31 c can make the light L 3 incident toward the second reflecting portion 33.

When viewed from the front of the lamp (that is, in a cross section perpendicular to the front-rear direction), the first reflecting portion 32 is formed to be a curve that collects and reflects incident light L2, such as a parabolic curve or an elliptic curve. And is provided continuously with one end of the second extending portion 37. Therefore, the light L <b> 2 incident from the second incident portion 31 b is internally reflected by the first reflecting portion 32 and guided toward the second extending portion 37.
Moreover, the 1st reflection part 32 is comprised by the linear form in the cross section perpendicular | vertical to the left-right direction. Thereby, the substantially parallel light viewed from the left side of the lamp from the second incident part 31b is reflected toward the second extending part 37 in the same substantially parallel direction.

When viewed from the front of the lamp (that is, in a cross section perpendicular to the front-rear direction), the second reflecting portion 33 is formed to be a curve that collects and reflects the incident light L3, such as a parabolic curve or an elliptic curve. And is provided continuously with one end of the third extending portion 38. Therefore, the light L3 incident from the third incident portion 31 c is reflected on the inner surface by the second reflecting portion 33 and guided into the third extending portion 38.
Further, the second reflecting portion 33 is configured in a straight line in a cross section perpendicular to the left-right direction. Thereby, the substantially parallel light seen from the left of the lamp from the second incident part 31b is reflected toward the third extending part 38 in the same substantially parallel direction.

  As shown in FIG. 4, the first extending portion 36 includes a front side surface portion 36 a and a rear side surface portion 36 b that faces the front side surface portion 36 a. A plurality of minute steps are provided on the rear side surface portion 36b. By this step, the light L1 guided into the first extending portion 36 is internally reflected forward and is irradiated forward from the front side surface portion 36a.

Similarly, with respect to the second extending portion 37 and the third extending portion 38, a plurality of minute steps are provided on the rear side surface portion, and by this step, the second extending portion 37 and the third extending portion 38 are provided. The light L2 and L3 guided to the inner surface are internally reflected forward and irradiated from the front side surface to the front of the lamp.
In this way, light is emitted from the entire front side surface portion along the longitudinal direction of the first to third extension portions 36 to 38.

  As described above, according to the vehicular lamp 10 of the present embodiment, the incident portion 31 of the light guide 30 causes the light from the light source 21 to be internally reflected toward the second extending portion 37. 32 and a second reflecting portion 33 that internally reflects light from the light source 21 toward the third extending portion 38. Therefore, even when the light guide 30 includes a plurality of extending portions 35 as in the present embodiment, it is not necessary to provide a plurality of light sources according to the number of extending portions 35. That is, each extension part 35 can emit light using only the light source 21. Thereby, the utilization efficiency of the light from the single light source 21 can be increased, and the cost can be reduced.

  In addition, according to the present embodiment, the first incident portion 31 a disposed on the optical axis of the light source 21 and the light incident on the first reflecting portion 32 disposed on one side of the first incident portion 31 a. A second incident portion 31b and a third incident portion 31c that is arranged on the other side of the first incident portion 31a and makes light incident on the second reflecting portion 3 are provided. Therefore, the lights L1 to L3 can be distributed so that the lights L1 to L3 from the light source 21 are substantially uniformly incident on the extending portions 35 in the first to third incident portions 31a to 31c. Thereby, each extension part 35 can be light-emitted substantially uniformly.

  Moreover, according to this embodiment, the light guided inside the light guide 30 is reflected by the front side surface side facing each other by the rear side surface portion along the longitudinal direction in each extending portion 35. The entire side surface of each extending portion 35 can emit light substantially uniformly.

  Furthermore, according to the present embodiment, in the vehicular lamp 10 used as the left tail lamp, the light source 21 supported by the support member 13 fixed to the left opening end of the lamp body 11 has an arc-shaped light guide in top view. 30 is provided so as to face the incident portion 31 which is the left rear end portion. Therefore, the light emitted from the light source 21 and incident from the incident portion 31 is efficiently emitted toward the front of the lamp while being guided inside the light guide 30.

Next, a modification of the present embodiment will be described with reference to FIG.
(Modification 1)
As shown in FIG. 5A, the first extending portion 136 includes a front side surface portion 136a that is a front surface of the lamp unit 120, a rear side surface portion 136b that faces the front side surface portion 136a, And an end portion 136c facing the incident portion 131a. Unlike the embodiment described above, the rear side surface portion 136b is not provided with a step. Therefore, a lot of light L4 out of the light guided into the first extending portion 136 is reflected by the inner surface of the front side surface portion 136a and the inner surface of the rear side surface portion 136b and is emitted from the end portion 136c. .

(Modification 2)
Further, as shown in FIG. 5B, the first extending portion 236 includes a front side surface portion 236a that is a front side surface of the lamp unit 220, a rear side surface portion 236b that is a rear side surface, And an end portion 236c facing the one incident portion 231a. Unlike the first modification, the end 236c is formed to be inclined from the rear side surface 236b to the front side surface 236a of the first extension portion 236. Further, the end portion 236c is provided with a reflection film made of, for example, an aluminum vapor deposition film on its end surface. Therefore, the light L5 guided to the end portion 236c among the light guided into the first extending portion 236 is totally reflected by the inner surface of the end portion 236c and emitted from the front side surface portion 236a.
In addition, it is good also as a structure by which reflection films, such as an aluminum vapor deposition film, are not provided in the end surface of the edge part 236c. According to this configuration, a part of the light guided to the end portion 236c out of the light guided into the first extending portion 236 is totally reflected or partially reflected by the inner surface of the end portion 236c, and the front side surface. Light that is emitted from the portion 236a and not reflected passes through the end portion 236c and is emitted from the end portion 236c.

As described above, according to the lamp units 120 and 220 according to the first and second modifications, the lights L4 and L5 guided inside the light guides 130 and 230 are transmitted through the first extending portions 136 and 236. The light is emitted from the end portion 136c facing the incident portion 31 or the front side surface portion 236a in the vicinity of the end portion 236c. Therefore, strong light can be emitted substantially uniformly from the vicinity of the end portions 136c and 236c of the first extending portions 136 and 236.
As in the above embodiment, a minute step is provided on each of the rear side surface portions 136b and 236b of the first extension portions 136 and 236, and the entire front side surface portions 136a and 236a and each end portion 136c, It is good also as a structure which radiate | emits light from both 236c.

(Second Embodiment)
Next, a lamp unit 320 according to a second embodiment of the present invention will be described with reference to FIG. The description of elements having the same or similar configuration and function as the lamp unit 20 in the first embodiment is omitted.

  As shown in FIG. 6A, in the lamp unit 320, an inner lens 340 is provided between the light source 21 and the first incident portion 331 a of the light guide 330. The inner lens 340 is made of, for example, glass or resin, and the surface facing the light source 21 is linear in a cross section perpendicular to the vertical direction and circular in a cross section perpendicular to the front and rear direction (that is, a cylindrical surface). The surface facing the first incident portion 331a is formed into a circular arc shape in a cross section perpendicular to the vertical direction and a circular arc shape (that is, a toroidal surface) in a cross section perpendicular to the front and rear direction.

  As shown in FIG. 6B, the light L6 that is off the optical axis Ax of the light source 21 and is emitted in the front-rear direction is refracted so as to be condensed in the front-rear direction by passing through the inner lens 340. It is comprised so that it may inject into incident part 331a, 331b, 331c. That is, the inner lens 340 emits the light L6 in a direction (vertical direction in FIG. 6B) perpendicular to a plane including the light source 21 and the first reflecting portion 332 and the second reflecting portion 333 of the light guide 330. The light can be condensed so as to approach a direction parallel to the axis Ax.

According to the lamp unit 320 of the present embodiment described above, the inner lens 340 also causes the light L6 in the vertical direction that cannot be incident on the incident portion 31 in the first embodiment among the light emitted from the light source 21. The light can be condensed in the vertical direction and incident on the incident portion 331. Therefore, the utilization efficiency of light from the light source 21 can be further increased.
In the first embodiment, the first incident portion 31a is formed so as to have a substantially hemispherical surface in order to refract the light L1 along the optical axis Ax. The light L6 can be collected by the lens 340. Therefore, as shown in FIG. 6B, the first incident portion 331a can have a planar shape in a cross section perpendicular to the vertical direction.

  In the above, the example of embodiment of this invention was demonstrated, However, This invention is not limited to the said embodiment, It is possible to employ | adopt another structure as needed.

  For example, in the above-described embodiment, the first to third extending portions 36 to 38 are each configured as a cylindrical long bar, and the second extending portion 37 and the third extending portion 38 are respectively the first extending portion. Although it is arranged in parallel with the extending part 36, it may have any shape as long as it is branched from the incident part 31 to form a plurality of extending parts 35. The shape of each extending portion 35 may be, for example, a rectangular shape or a polygonal shape in a cross-sectional view perpendicular to the longitudinal direction, or a shape obtained by combining these.

  Further, in the above embodiment, the light guide 30 is formed to have an arc shape in a top view according to the shape of the outer cover 12, but it may have any shape such as a linear shape or a bent shape. Good.

  Moreover, in said embodiment, although the light guide 30 is comprised by integrating the incident part 31 and the some extension part 35, this invention is not limited to this example. For example, the incident portion 31 and the plurality of extending portions 35 may be configured separately and connected to each other.

  In addition, the vehicular lamp 10 can be used not only as a tail lamp, but also as other vehicular lamps such as a headlamp and a turn signal lamp, if necessary.

  10: vehicle lamp, 11: lamp body, 12: outer cover, 20: lamp unit, 21: light source, 30: light guide, 31: incident part, 31a: first incident part, 31b: second incident part, 31c: 3rd incident part, 32: 1st reflection part, 33: 2nd reflection part, 35: Extension part, 36: 1st extension part, 36a: Front side part, 36b: Back side part, 36c: End Part 37: second extension part 38: third extension part 340: inner lens

Claims (5)

A light source;
A light guide having an incident portion on which light from the light source is incident, and a plurality of extending portions that branch out from the incident portion and emit the light;
With
The plurality of extending portions include a first extending portion having a portion extending on the optical axis of the light source, and the first extending portion extending along a longitudinal direction of the first extending portion. A second extension portion arranged in parallel with one side of the extension portion, and a third extension extended along the longitudinal direction of the first extension portion and arranged in parallel with the other side of the first extension portion And including
The incident portion includes a first reflecting portion that internally reflects the incident light toward the second extending portion, and a second reflection that internally reflects the incident light toward the third extending portion. And a vehicle lamp characterized by comprising: The incident portion is
A first incident portion disposed on the optical axis;
A second incident part that is disposed on one side of the first incident part and allows light from the light source to enter the first reflecting part;
A third incident part disposed on the other side of the first incident part and allowing light from the light source to enter the second reflecting part;
The vehicular lamp according to claim 1, comprising:   The light guided within the light guide is emitted from each side surface portion along the longitudinal direction in the first extension portion, the second extension portion, and the third extension portion. Item 3. A vehicle lamp according to item 1 or 2.   The light guided inside the light guide is emitted from each end of the first extending portion, the second extending portion, and the third extending portion that faces the incident portion. Item 3. A vehicle lamp according to item 1 or 2. An inner lens is provided between the light source and the incident part,
The said inner lens condenses the light from the said light source in the direction orthogonal to the plane containing the said light source, the said 1st reflection part, and the said 2nd reflection part, and makes it inject into the said incident part. The vehicle lamp according to any one of the above.

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