JP6109652B2 - LED light source unit and illumination device provided with light guide - Google Patents

Description

  The present invention relates to a light source LED light source unit including a transparent light guide and an LED (light emitting diode) light source that emits toward the light guide, and an illumination device including the same.

  2. Description of the Related Art Conventionally, LEDs using LEDs as light sources for vehicle lamps have been put into practical use in order to reduce power consumption. In addition, with the recent increase in luminance of LEDs, there is also known a vehicular lamp in which the number of LEDs to be used is reduced by forming a light emitting surface using a light guide. For example, in Patent Document 1, two long light guide bars are used as light guides, and two light guide bars are caused to emit light at one light emitting unit.

  FIG. 11 is a front view of the vehicular lamp described in Patent Document 1. FIG. FIG. 12 is a side view showing a light source unit described in Patent Document 1. As shown in FIG. The vehicular lamp 1 is a rear lamp disposed at a rear end of a vehicle (not shown), and includes two long light guide rods 3 and 3 in a lamp chamber whose front surface is covered with a plain lens cover 2. . The light guide rods 3 and 3 are rod-like light emitting members that emit light entirely from the light while propagating light incident from the end portions along the longitudinal direction. A light source portion L for causing the light guide rods 3 and 3 to emit light is provided in a portion where the end portions of the light guide rods 3 and 3 are close to each other, as shown in FIG. LEDs 4 and 4 are installed.

JP 2012-169116 A

  As a usage form of the vehicular lamp, there is a demand to switch on the light emission color by the light guide according to the usage scene. For example, in a license plate lamp for displaying a license plate of an automobile, when the light guide bar emits light around the license plate and the light emission color is to be switched, the LED 4 incident from the end face of the light guide bar 3 is used. It is only necessary to switch the emission color.

  The following two measures can be considered as a method of switching the emission color of the LED 4. As a first countermeasure, a structure in which LEDs emitting two different emission colors are arranged in parallel instead of one LED 4 facing the end face of one light guide bar 3. As a second countermeasure, instead of one single-color LED 4 opposed to the end face of one light guide bar 3, a multi-color LED 4 in which LED chips emitting different emission colors are incorporated in one LED 4 is used. .

  However, in the case of the first countermeasure, the utilization efficiency of light incident from the end face of the light guide bar 3 is lowered. In addition, the light source unit is increased in size. In the case of the second countermeasure, since the multicolor light emitting LED generally has a lower luminance than the single color light emitting LED having the same cost, it is difficult to obtain a bright light emitting color at the same cost. Moreover, since the light emitting surface of the light guide is irradiated, that is, the optical path is the same, only the same orientation pattern can be obtained even when the LED emission color is switched, giving a monotonous impression to the observer. There was room for improvement in appearance merchandise.

  The present invention has been made in view of the above circumstances, and is a vehicle lamp that emits light of different colors from the same light guide rod and can change the light distribution pattern at the same time and has excellent appearance merchandise. Offering is an issue.

  In order to solve the above-described problems, the present invention provides a second plate-shaped light guide behind the light guide bar, and emits light by the first light incident from the end face of the light guide bar. The main feature is that light is emitted by the second light incident on the second plate-shaped light guide and emitted through the second plate-shaped light guide and the light guide rod.

  According to the present invention, from the same rod-shaped light guide surface (light emitting surface), the light from the first subunit composed of the first rod-shaped light guide and the LED light source, and the plate-like shape provided at a predetermined position Since the LED light source unit composed of the second subunit composed of the light guide and the LED light source is used, the light emitted from the first sub LED light source unit and the second sub LED are emitted from the light emitting surface of the first rod-shaped light guide. Both light distribution patterns of light emission by the light source unit can be obtained. Thereby, the vehicular lamp excellent in appearance merchandise can be obtained.

FIG. 1 is a schematic front view showing a license plate mounting portion of a vehicle according to the first embodiment. 2 is a schematic front view showing the license plate lamp of FIG. 1 with the lens cover removed. FIG. 3 is a perspective view of the light guide and the LED shown in FIG. 2 viewed obliquely from above. FIG. 4 is an enlarged cross-sectional view of the light source coupling portion of the light guide unit according to the first embodiment. FIG. 5 is a schematic cross-sectional view of the first rod-shaped light guide according to the first embodiment cut along a horizontal plane. FIG. 6 is a schematic cross-sectional view of the second rod-shaped light guide according to the first embodiment cut along a plane extending in the front-rear direction. FIG. 9 is a schematic cross-sectional view of the LED light source unit according to the first embodiment, in which the first rod-shaped light guide and the plate-shaped light guide are cut along a horizontal plane. FIG. 8 is a schematic perspective view of the plate-like light guide according to the first embodiment viewed from the upper rear side. FIG. 9 is a schematic cross-sectional view of the LED light source unit according to the second embodiment, in which the first rod-shaped light guide and the plate-shaped light guide are cut along a horizontal plane. FIG. 10 is a schematic perspective view showing a main part of the vehicular lamp according to the third embodiment. FIG. 11 is a front view of a conventional vehicular lamp. FIG. 12 is a side view showing a light source part of a conventional vehicular lamp.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.
In the following description, unless otherwise specified, the descriptions in the vertical direction and the horizontal direction refer to a practical state of the lighting device, for example, a direction when the lamp is mounted on the vehicle, and the front refers to the main irradiation of the lighting device. It is assumed that the direction indicates the opposite side of the front from the rear and is used in correspondence with the description in the drawings.

(First embodiment)
A vehicle license plate lamp will be described as an example of the illumination device of the present embodiment. FIG. 1 is a schematic front view showing a license plate mounting portion of a vehicle. As shown in FIG. 1, in the illumination device 10 of the present embodiment, the light emitting surface 12 is provided around the license plate mounting portion 13. The light emitting surface 12 is covered with a lens cover (not shown) having translucency. The vehicle license plate lamp 10 is fitted and fixed in a recess (not shown) provided in the vehicle 14.

  FIG. 2 is a schematic front view showing the license plate lamp 10 of FIG. 1 with the lens cover removed, and FIG. 3 is a view of the light guides 21, 22, 31 and the LED 4 shown in FIG. FIG. An LED light source unit using a light guide and an LED light source is housed in a lamp chamber in the lamp. Reference numeral 21 denotes a first bar-shaped light guide that forms the light emitting surface 11, and reference numeral 22 denotes a second bar-shaped light guide that forms the light emitting surface 12. A side surface viewed on the front side of each of the rod-shaped light guides 21 and 22 is an emission surface. Moreover, LED4 is installed as a light source in the edge part of the extension direction of the rod-shaped light guide 21 extended in the horizontal direction, and the edge part of the extension direction of the rod-shaped light guide 22 extended in the horizontal direction. A plate-shaped light guide 31 is disposed behind the rod-shaped light guide 21.

  FIG. 4 is an enlarged sectional view showing the light source coupling portion 40 of the light guide unit. The first rod-shaped light guide 21 is a rod-shaped light guide that extends in a line along the outer shape of the vehicle lamp in the horizontal direction of the vehicle, and is formed of a transparent injection moldable material such as acrylic resin or polycarbonate resin. Has been. As shown in FIG. 4, the light source coupling member 41 b fixes the end surface 21 a of the first rod-shaped light guide 21 and the emission surface 41 a of the first LED 41 at the end of the light guide. . This forms the first subunit.

  The light source coupling member 41 b has a recess that matches the outer shape of the first rod-shaped light guide 21 and an attachment hole that fixes the LED 41 formed on the bottom surface of the recess. Thereby, the LED 41 is fixed and at the same time, the light emitted from the LED is prevented from leaking to the outside. The light source coupling member 41b is preferably formed of a light-shielding material having high thermal conductivity and excellent heat dissipation, such as a ceramic material. By making the LED 41 and the first rod-shaped light guide 21 have better heat dissipation, heat generated from the LED 41 can be efficiently radiated, and problems associated with the temperature rise of the LED 41 can be reduced. It is. In addition, the end surface 21 a of the first rod-shaped light guide 21 is an incident surface, and the light L1 emitted from the center of the exit surface of the LED 41 is refracted into the light guide 21 as a convex shape toward the LED chip 41 a of the LED 41. It is assumed that the light enters the first light guide 21 and travels substantially in parallel along the extending direction in the first light guide 21. Thereby, the loss amount of the light beam L1 incident on the light guide is reduced.

  FIG. 5 is a schematic cross-sectional view of the first rod-shaped light guide 21 cut along a horizontal plane. In FIG. 5, the configuration of the light source coupling unit 40 is omitted. On the incident / reflecting surface 21b, wedge-shaped notches 21c and flat surfaces 21d are alternately and repeatedly formed. In FIG. 5, the light from the LED 41 that enters the first rod-shaped light guide 21 from the end face 21a is indicated by a solid line, and the light from a plate-shaped light guide 31 described later is indicated by a dotted line. The light beam incident from the end face 21a travels through the first rod-shaped light guide 21, and part of the light reaches the incident / reflecting face 21b. Of the light traveling toward the incident / reflecting surface 21b, the light reaching the wedge-shaped cutout 21c is internally reflected at the interface between the light guide 21 and the external atmosphere and travels toward the opposite side surface. The opposite side surface is the light emitting surface 11.

  FIG. 6 is a schematic cross-sectional view of the second rod-shaped light guide 22 cut along a plane extending in the front-rear direction. The third subunit is configured by providing a light source coupling portion for fixing the LED 42 on the end face of the second light guide 22. Since the configuration of the light source coupling portion is the same as that of the light source coupling portion 40 provided in the first rod-shaped light guide 21 shown in FIG. 4, description thereof is omitted here. A wedge-shaped notch 22c is formed on the reflecting surface 22b. The difference from the reflective surface 21b of the first rod-shaped light guide 21 is that a flat surface is not formed between the adjacent wedge-shaped notches 22c. The light beam incident from the end surface 22a travels through the second rod-shaped light guide 22, and a part of the light beam reaches the reflection surface 22b. Of the light traveling toward the reflecting surface 22b, the light reaching the wedge-shaped cutout 22c is internally reflected at the interface between the light guide 21 and the external atmosphere and travels toward the opposite side surface. The opposite side surface is the light emitting surface 12.

  As shown in FIGS. 3 and 2, the plate-like light guide 31 is a plate-like member parallel to a plane extending in the front-rear direction and the left-right direction, and is provided behind the first rod-like light guide 21. ing. FIG. 7 is a schematic perspective view of the plate-shaped light guide body 31 as viewed from the obliquely upper rear side. The upper plate surface 31a and the rear plate surface 31b are substantially parallel, and the emission end surface 31c on the first rod-shaped light guide 21 side that is the emission surface is formed as an uneven surface. The light incident portion 32 is provided at the corner of the end surface 31d corresponding to the upper base when the trapezoidal shape is formed in a top view and the lower base of the trapezoid is the emission end surface 31c. This constitutes the second subunit.

  The light incident part 32 is provided on both sides of the incident surface 32a having a convex shape facing the LED 43 on the optical axis of the LED 43 for the plate-shaped light guide, and light that spreads from the optical axis of the LED and irradiates the light. Are incident on the side incident surface 32b and a reflection surface 32c for reflecting the light incident from the side incident surface 32b. By adjusting the shape of the incident surface 32a, direct light incident from the LED 43 is expanded toward the emission end surface 31c. Further, by adjusting the shapes of the side incident surface 32b and the reflecting surface 32c, light having a low light intensity emitted in an oblique direction from the LED 43 is also supplemented and used. The other end surfaces 31d, 31e, 31f and the plate surfaces 31a, 31b are also used as inner reflection surfaces of the light incident from the light incident part 32.

  As shown in FIGS. 5 and 7, the emission end face 31 c of the plate-like light guide 31 is disposed to face the incident / reflecting surface 21 b of the first rod-like light guide. Therefore, the light emitted from the emission end face 31c travels toward the incident / reflecting surface 21b of the first rod-shaped light guide member. At this time, the light incident from the vertical direction with respect to the flat surface 21d of the incident / reflecting surface 21b passes through the first rod-shaped light guide 21 as shown in FIG. It exits from the surface 11 (light ray L3). A part of the light that is emitted in an oblique direction with respect to the emission end face 31c of the plate-like light guide 31 and is incident on the inclined surface of the wedge-shaped notch 22c of the incident / reflection surface 21b from the vertical direction is also the first. It passes through the rod-shaped light guide 21 and exits from the emission surface of the rod-shaped light guide, that is, the light emitting surface 11.

  As shown in FIG. 8, the plate-shaped light guide 31 has one substantially trapezoidal flat plate as one unit as shown in FIG. 7 and is integrally formed by connecting the emission end face 31c side. It is one continuous sheet. Thereby, even when it becomes a curve in the elongate direction of the 1st rod-shaped light guide 21, it can track the curvature. In addition, it is good also as the plate-shaped light guide 31 of only 1 unit.

  In addition, each of the LEDs 41, 42, and 43, which are the light sources of the light guides 21, 22, and 23, is connected to a lighting control device (not shown) that can be controlled to light independently.

  Next, the lighting state of the license plate lamp 10 of the present embodiment will be described. When only the LED 41 is lit, the light emitted from the LED 41 is emitted from the light emitting surface 11 through the first rod-shaped light guide 21. That is, the upper part of the paper surface in FIG. 1 emits light in a line shape. At this time, when the LED 42 provided on the left light guide 22 and the LED 42 provided on the right light guide 22 are turned on at the same time, a linear light emitting surface is formed so as to surround the upper side and the side side of the license plate mounting portion 13. . This lighting state is defined as a first lighting state.

  Next, the LED 41 is turned off, and the LED 43 attached to the plate-shaped light guide 31 is turned on instead. The light emitted from the LED 43 is incident on the plate-shaped light guide 31, then exits from the light emission end surface 31 to the outside of the light guide 31, and then exits from the light emitting surface 11 through the first rod-shaped light guide 21. To do. That is, the upper part of the paper surface in FIG. 1 emits light in a line shape. At this time, the lighting color of the LED 42 provided on the left light guide 22 and the LED 42 provided on the right light guide 22 is different from the lighting color of the LED 43 attached to the plate-like light guide 31. Thereby, in the point which is a line-shaped light emission surface which surrounds the upper side and side edge of the license plate mounting part 13, although it is the same as lighting of LED41, the illumination by which the light emission surface of the upper side was switched to light emission of a different color is made. . This lighting state is defined as a second lighting state.

  Comparing the first lighting state and the second lighting state, the light emission from the light emitting surface 11 emits light with different emission colors in the first lighting state and the second lighting state. Furthermore, the orientation pattern of the light emitting surface 11 is different between the first lighting state and the second lighting state. This is because the emission position of the main light beam emitted from the first rod-shaped light guide is different between the light beam in the first lighting state and the light beam in the second lighting state. That is, it is possible to irradiate the line-shaped multicolor light emission from the side surface of the rod-shaped light guide by changing the light distribution pattern.

(Second Embodiment)
FIG. 9 is a schematic cross-sectional view of the LED light source unit in which the first rod-shaped light guide 21 and the plate-shaped light guide 31 are cut along a horizontal plane, and corresponds to FIG. 5 of the first embodiment. The second embodiment differs from the first embodiment in that a control element 31d for controlling the emission direction is formed on the emission end face 31c of the plate-like light guide 31.

  The control element 31d is a concave surface formed in a region facing the flat surface 21d when the plate-shaped light guide 31 is disposed facing the incident / reflecting surface 21b of the first rod-shaped light guide 21. . Of the light rays emitted from the emission end face 31c of the plate-shaped light guide 31, the refraction direction of the light emitted from the control element 31d is adjusted to increase the light rays toward the corresponding flat surface 21d. That is, the directivity of light toward the flat surface 21d is increased.

  In the first lighting state, light traveling in a direction perpendicular to the first rod-shaped light guide is emitted with the highest intensity from the region corresponding to the inclined surface of the wedge-shaped notch 22c. In the second lighting state, light traveling in a direction orthogonal to the first rod-shaped light guide from the region corresponding to the flat surface 21d is emitted with the strongest intensity. In the second embodiment, a control element 31d for controlling the emission direction is formed on the emission end surface 31c of the plate-shaped light guide 31 corresponding to the flat surface 21d. Thereby, the light distribution pattern in a 2nd lighting state can be adjusted independently of a 1st lighting state.

  In addition, adjustment of each orientation pattern of a 1st lighting state and a 2nd lighting state is not restricted to said embodiment. A control element may be provided on a flat surface. In addition, both the first lighting state and the second lighting state can be achieved by applying a fine unevenness to the light emitting surface 11 of the first rod-shaped light guide so as to diffuse and emit in various directions. A diffused light distribution pattern may be obtained as the diffuse light emitting surface. Further, by illuminating both the LED 41 and the LED 43, the irradiation light from the light emitting surface 11 can be combined light of the lighting state 1 and the lighting state 2.

(Third embodiment)
FIG. 10 is a schematic perspective view showing a main part of a vehicular lamp in which the LED light source unit described in the first embodiment is applied to a vehicular rear lamp. An LED light source unit 50 using a light guide is housed in a lamp chamber formed by a lamp housing (not shown) and a lens cover. The extension 55 is installed between the LED light source unit 50 and the lens cover. The three holes 55a provided in the extension 55 correspond to a place where a lamp unit that performs illumination of a function of a rear lamp such as a turn lamp (not shown) is provided. A recess 55b including two hole portions 55a is provided on the surface of the extension. A mounting groove 55c is formed so that the light emitting surface of the rod-shaped light guide of the LED light source unit 50 is positioned above and below the hole 55a in the recess 55b. In FIG. 10, the mounting groove 55c is simplified and represented by a line. The extension 55 is a decorative member that covers the periphery of the lamp unit provided in the hole and shields the housing from being directly observed through the lens cover. Therefore, the light source coupling portion 40 provided at the end of the rod-shaped light guide is also positioned on the back surface of the extension 55 so that it is difficult to observe the light source coupling portion 40 from the front of the lamp (rear of the vehicle).

  The LED light source unit 50 has the same characteristics as the light guide unit described in the first embodiment. From the 1st subunit 51 which consists of LED41 provided in the 1st rod-shaped light guide 21 and its end, the plate-shaped light guide 31 and LED43 which were provided in the back side of the 1st rod-shaped light guide 21 A second subunit 52, a rod-shaped light guide 22 extending downward from the right end of the rod-shaped light guide 21 of the first subunit, and a third subunit 53 comprising an LED 42 provided at the end. Is provided. Since the configurations of the first subunit, the second subunit, and the third subunit are the same as those of the light guide and the LED described in the first embodiment, description thereof is omitted here. The same reference numerals as those in the first embodiment are given.

  In the third embodiment, a fourth subunit 54 is further provided. The fourth subunit 54 is disposed below the two holes 55a of the extension 55 so as to be positioned in the recess 55b. The fourth subunit 54 has the same configuration as that of the third subunit. That is, it is composed of a rod-shaped light guide 22 extending downward from the right end portion of the rod-shaped light guide 21 of the first subunit and an LED 42 provided at the end portion, and the light from the LED 42 provided at the end portion is formed into a rod shape. Light reflected by the reflecting surface 2b provided on the rear side surface of the light guide 21 and reflected by the reflecting surface 22b is emitted from the light emitting surface which is the side surface of the rod-shaped light guide. Thereby, the outer periphery of a vehicle lamp can be made to shine.

  The above embodiment is merely an example in all respects. The present invention is not construed as being limited to these descriptions. For example, although the light incident part 32 is provided on the end surface of the plate-shaped light guide 31, a structure in which the light incident part is provided on the plate surface 31a and the reflection surface is provided at a corresponding position on the plate surface 31b may be employed. The present invention can be implemented in various other forms without departing from the spirit or main features thereof.

  The present invention can be used for vehicle lamps such as a head lamp, a fog lamp, a tail lamp, a parking lamp, a clearance lamp, a stop lamp, a turn signal lamp, a side marker lamp, and a backup lamp.

DESCRIPTION OF SYMBOLS 1 Vehicle lamp 2 Lens cover 3 Light guide rod 31 Incident surface 32 Reflective surface 4 LED
L Light source 10 Signal lamp for vehicle (lighting device)
DESCRIPTION OF SYMBOLS 11, 12 Light emission surface 13 License plate mounting part 14 Car body 15 Housing 21 1st rod-shaped light guide 21a End surface 21b Incidence reflective surface 21c Wedge-shaped notch 21d Flat surface 22 2nd rod-shaped light guide 22a End surface 22b Reflective surface 22c Wedge-shaped notch 31 Plate-shaped light guide 31a, 31b Plate surface 31c Emission end surface 31d-31f End surface 31d Control element 32 Light incident part 32a Incident surface 32b Side incident surface 32c Reflective surface 40 Light source coupling part 41, 42 1st LED
41a Emission surface 41b Light source coupling member 43 Second LED
50 LED light source unit 51-54 Sub unit 55 Extension 55a Hole 55b Recess 55c Groove

Claims (3)

An LED light source unit that has at least two LED light sources having a first LED light source and a second LED, and a light guide having an incident surface on which light emitted from the LED light source is incident, and emits light from a linear light emitting surface Because
The light guide has a rod-shaped first light guide and a plate-shaped second light guide,
The first light guide is provided at an end of the first light guide incident surface on which light from the first LED light source is incident, a first light guide reflecting surface provided on a side surface extending in the longitudinal direction, and A first light guide emitting surface, and the first light guide reflecting surface is inclined with respect to the first light guide flat surface along the longitudinal direction and the first light guide flat surface. A first light guide inclined reflection surface is formed,
The second light guide is provided on an end surface or a plate surface and is incident on the second light guide incident surface on which light from the second LED light source is incident, and is incident on the second light guide from the second light guide incident surface. A second light guide reflecting surface for reflecting the reflected light and an end face emitting surface provided on the end face,
The end face exit surface of the second light guide is disposed to face the first light guide reflector along the longitudinal direction of the extension of the first light guide,
The first light guide emitting surface includes a light beam emitted from the first LED light source through the first light guide, and a light emitted from the second LED light source to the second light guide and the second light guide. An LED light source unit characterized in that it can emit both light rays emitted through the first light guide. One of the first light guide and the first LED light source;
Comprising at least two second light guides and a second LED light source;
2. The end face exit surface of each of the two second light guides is integrally formed side by side in a longitudinal direction in which the first light guide extends. LED light source unit. The LED light source unit according to claim 1;
A housing for housing the LED light source unit;
A lens cover that is positioned in front of the first light guide emitting surface and is attached to the housing;
A lighting device capable of independently controlling lighting of the first LED and the second LED;
A vehicular lamp characterized in that a first light distribution pattern obtained when only the first LED is turned on differs from a second light distribution pattern obtained when only the second LED is turned on.

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