LED LIGHT SOURCE MODULE [Technical Field]

[0001] The present invention relates to an LED (light emit ^¬ ting diode) light source module for a lighting apparatus for a vehicle.

[Background Art]

[0002] Typically, a current vehicle head light uses a halogen bulb as a light source. Hereafter, it is thought that em ^¬ ployment of a head light (also called LED head light using LED as a light source will progress, but when an internal temperature (junction temperature) of the LED approaches a maximum junction temperature of the LED due to self-heating, such a drawback as reduction in light flux, change in emis ^¬ sion color, reduction of luminance, or shortening of an operating life occurs. Therefore, a strict heat control is re ^¬ quired . [0003] As a conventional LED head light, an arrangement in which a heat sink is provided on a supporting body of an LED and an electric fan is arranged to face the heat sink is known. In such an LED head light, the LED is forcibly cooled by forcibly circulating air within a lighting chamber with the electric fan to promote a dissipation of heat from the heat sink. (See Patent Document 1)

[Prior Art Document]

[Patent Document]

[0004]

[Patent Document 1]

JP Patent Appl . Publ . No. 2010-262903 [Summary of the Invention]

[Problem to be Solved by the Invention]

[0005] However, since the conventional LED head light dis ^¬ closed in Patent Document 1 is configured such that an LED light source is integrated with a lighting apparatus main body, when the necessity of replacement of the LED light source arises, the LED head light itself must be replaced.

[0006] The problem to be solved by the present invention is to provide an LED light source module which can replace a ha- logen bulb or the like generally used as a light source for a lighting apparatus for a vehicle.

[Means for Solving the Problem]

[0007]

[Configuration 1]

An LED light source module of the present invention is a re ^¬ placeable light source module for a lighting apparatus for a vehicle, comprising:

an LED light source having a single or a plurality of LED chips ;

a heat sink thermally connected to the LED light source;

an electric fan unit cooling the heat sink by air blasting; a driver circuit driving the LED light source and the elec ^¬ tric fan unit; and

an attachment detachably fitted into a light source mounting hole of a lighting apparatus for a vehicle,

wherein

all of the LED light source, the heat sink, the electric fan unit, the driver circuit, and the attachment are configured integrally, the LED light source is directly mounted on the heat sink, the heat sink is provided between the LED light source and the electric fan unit, the attachment has a sup ^¬ porting frame projecting into a lighting chamber of the ligh- ting apparatus for a vehicle, the electric fan unit is pro ^¬ vided at a distal end portion of the supporting frame, the driver circuit is provided on the supporting frame, and all of the LED light source, the heat sink, the electric fan unit, and the driver circuit are housed in the lighting cham ^¬ ber of the lighting apparatus for a vehicle through the light source mounting hole.

[0008] The LED light source module configured in the above manner can replace a halogen bulb or the like when the LED light source module has the same attachment structure as that of the halogen bulb or the like generally used as a light source for a lighting apparatus for a vehicle. When the LED light source module needs replacement, unlike the conven ^¬ tional case where the whole arrangement is replaced, only the LED light source module can be replaced.

Since the LED light source module is configured such that the LED light source is directly mounted on the heat sink, a heat exchange between the LED light source and the heat sink can be performed with high efficiency. Therefore, the LED light source can be cooled efficiently by cooling the heat sink with air flowing from the electric fan unit. Accordingly, the LED light source module with a compact and inexpensive configuration can be realized by using an electric fan unit with a relatively small total amount of air. [0009]

[Configuration 2]

The LED light source module according to Configuration 1, wherein the heat sink and the driver circuit are adjacent to each other, and the heat sink has an internal flow passage designed such that air or any other suited gaseous cooling medium supplied from the electric fan unit can be guided to the driver circuit. [0010]

[Configuration 3]

The LED light source module according to Configuration 1, wherein a stacking direction of the LED light source, the heat sink, and the electric fan unit is a diametrical direc ^¬ tion of the attachment, i.e., a diametrical direction of the light source mounting hole.

[0011]

[Configuration 4]

The LED light source module according to any one of Configu ^¬ rations 1 to 3, wherein the LED light source has a substrate joined to the heat sink, the substrate has a first mounting surface and a second mounting surface, the first mounting surface and the second mounting surface are different from each other in distance from the heat sink, a first LED chip is mounted on the first mounting surface, and a second LED chip is mounted on the second mounting surface.

[0012]

[Configuration 5]

The LED light source module according to any one of Configu ^¬ rations 1 to 3, wherein the LED light source has a substrate joined to the heat sink, the substrate has a first mounting surface and a second mounting surface, the first mounting surface is inclined toward the second mounting surface, a first LED chip is mounted on the first mounting surface, and a second LED chip is mounted on the second mounting surface.

[0013]

[Configuration 6]

The LED light source module according to any one of Configu- rations 1 to 3, wherein the heat sink is provided on both si ^¬ des of the electric fan unit, and the LED light source is di ^¬ rectly mounted on each of the heat sinks. _r

b

[0014]

[Configuration 7]

The LED light source module according to any one of Configu ^¬ rations 1 to 3, wherein the attachment has a gasket for seal- b ing the light source mounting hole.

[Effect of the Invention]

[001b] According to the present invention, a replaceable LED light source module can be realized.

10 The LED light source module of the present invention can re ^¬ place a halogen bulb or the like when the LED light source module has the same attachment structure as that of the halo ^¬ gen bulb or the like generally used as a light source for a lighting apparatus for a vehicle.

lb

[Brief Description of the Drawings]

[0016] FIG. 1 is a perspective view illustrating an LED light source module of the present invention and a head light which can use this LED light source module as a light source;

20 FIG. 2 is a schematic sectional view showing an internal

structure of the head light;

FIG. 3 is a perspective view showing a first embodiment of the LED light source module of the present invention;

FIG. 4 is a side view of the LED light source module shown in 2b FIG. 3;

FIG. b is a rear view of the LED light source module shown in FIG. 3;

FIG. 6 is a perspective view of a heat sink;

FIG. 7 is an explanatory view showing that an LED light sour- 30 ce, a heat sink, an electric fan unit, and a driver circuit are all within a projection plane viewed in an insertion direction of an attachment into a light source mounting hole; FIG. 8 is a sectional view showing a state in which the LED light source module shown in FIG. 3 has been mounted on a head light main body;

FIG. 9 is a side view showing a second embodiment of the LED light source module of the present invention;

FIG. 10 is a side view showing a third embodiment of the LED light source module of the present invention;

FIG. 11 is a side view showing a fourth embodiment of the LED light source module of the present invention;

FIG. 12 is a sectional view showing a state in which the LED light source module according to a fifth embodiment of the present invention has been mounted on a head light main body; FIG. 13 is a perspective view showing another embodiment of the LED light source module of the present invention;

FIG. 14 is a front view of the LED light source module shown in FIG. 13; and

FIG. 15 is a sectional view of the LED light source module shown in FIG. 13. [Description of the Preferred Embodiments]

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]

FIG. 1 shows a head light 51 and an LED light source module 1 of the present invention. FIG. 2 shows an internal structure of the head light 51.

The head light 51 illustrated in FIG. 1 is a general type of lamp using a halogen bulb as a light source.

As shown in FIG. 2, the head light 51 has a reflector 52.

The reflector 52 has a largely-opened light emitting opening 53 at a front end thereof. The light emitting opening 53 is fitted with a lens 55. The entire inner surface of the re ^¬ flector 52 constitutes a reflecting surface. A rear end por- tion of the reflector 52 is curved in a dome shape, and light emitted from a halogen bulb (light source module) 60 is re ^¬ flected and guided forward by a reflecting surface 52a of the curved portion. A light source mounting hole 54 for mounting the halogen bulb (light source module) 60 is provided at a central portion of the rear end portion of the reflector 52. A fitting portion 57 for detachably mounting the halogen bulb (light source module) 60 is formed at the light source mount ^¬ ing hole 54. [0018] As shown in FIGS. 3 and 4, the LED light source module

1 has an LED light source 2, a heat sink 3, an electric fan unit 4, a driver circuit 5, and an attachment 6, and all of these constituent elements are integrated.

[0019] The LED light source 2 is directly mounted on the heat sink 3. The LED light source 2 is composed of a single or a plurality of LED chips 2a, and an LED supporting portion 2b which supports the LED chip 2a. The LED light source 2 has an emission performance of at least 350 lm, preferably about

2000 lm. [0020] The heat sink 3 is arranged between the LED light source 2 and the electric fan unit 4.

As shown in FIG. 6, the heat sink 3 has a flat plate portion 3a, a plurality of fins 3b, and side plate portions 3c sur ^¬ rounding the fins 3b. The shape of the flat plate portion 3a is roughly square. The LED light source 2 is directly moun ^¬ ted on a surface of the flat plate portion 3a. The fins 3b are projected perpendicularly from the back surface of the flat plate portion 3a. The fins 3b are arranged in a grid shape. The side plate portions 3c are provided along three of four sides of the flat plate portion 3a. ₀

o

[0021] The electric fan unit 4 includes a fan 4a within a ca ^¬ sing body 4b thereof. The amount of air of the fan 4a is se ^¬ lected on the basis of measurement results of an amount of heat generation of the LED light source 2, a thermal resis- tance of the heat sink 3, or the like. A space with a suffi ^¬ cient capacity is provided in the casing body 4b for good air suction and air blasting by the fan 4a. The electric fan unit 4 has an air blasting performance by which the junction temperature of the LED light source 2 with an emission per- formance of 350 lm or more can be kept at or below a reference temperature (about 150°C) at which the LED light source 2 can operate stably.

[0022] The driver circuit 5 is to drive the LED light source 2 and the electric fan unit 4. The driver circuit 5 is com- posed of various electronic components 5a. Further, the driver circuit 5 is electrically connected to the LED light source 2 and the electric fan unit 4.

[0023] The attachment 6 has an attachment main body 6A and a supporting frame 6B .

The attachment main body 6A is detachably fitted into the light source mounting hole 54 of the head light 51. A struc ^¬ ture of a portion 6A1 of the attachment main body 6A fitted into the light source mounting hole 54 is the same as that of an attachment portion of the halogen bulb (light source mod- ule) 60. An O-ring (gasket) 7 for air-tightly sealing a space between the attachment main body 6A and the fitting portion 57 of the light source mounting hole 54 is provided on the portion 6A1.

The supporting frame 6B projects from a front end 6A2 of the attachment main body 6A into the lighting chamber 56 of the head light 51 when the attachment main body 6A is fitted into the light source mounting hole 54 of the head light 51. The _

y attachment main body 6A has power plugs 8 and signal termi ^¬ nals (not shown) (see FIG. 5) .

[0024] The electric fan unit 4 is provided at a distal end portion of the supporting frame 6B . The driver circuit 5 is provided on the supporting frame 6B and located between the heat sink 3 and the attachment main body 6A. The heat sink 3 is fixed onto the casing body 4b of the electric fan unit 4 such that an end portion of the heat sink 3 not provided with the side plate portion 3c faces the driver circuit 5. The side plate portions 3c of the heat sink 3 are joined air ^¬ tight to the casing body 4b of the electric fan unit 4. With this configuration, the air flowing from the electric fan unit 4 flows into a space surrounded by the flat plate por ^¬ tion 3a and the side plate portions 3c of the heat sink 3 so as to be used to cool the LED light source 2 through heat ex ^¬ changes with the fins 3b and the side plate portions 3c, and is then guided to the driver circuit 5.

[0025] The attachment main body 6A has the largest diameter of the constituent elements of the LED light source module 1. A stacking direction of the LED light source 2, the heat sink 3, and the electric fan unit 4 is a diametrical direction of the portion 6A1 of the attachment main body 6A fitted into the light source mounting hole 54, i.e., a diametrical direc ^¬ tion of the light source mounting hole 54. [0026] As shown in FIG. 7, the LED light source module 1 is designed such that the LED light source 2, the heat sink 3, the electric fan unit 4, and the driver circuit 5 are all within a projection plane S viewed in an insertion direction of the portion 6A1 into the light source mounting hole 54. Specifically, as shown in FIG. 8, the LED light source module 1 is configured such that the LED light source 2, the heat sink 3, the electric fan unit 4, and the driver circuit 5 can all be housed in the lighting chamber 56 through the light source mounting hole 54. Sizes, shapes, and arrangements of these constituent elements are selected such that when the attachment main body 6A is attached rightly to the light source mounting hole 54, the LED light source 2 is accurately located with respect to the reflecting surface 52a of the re ^¬ flector 52.

[0027] As described above, in the LED light source module 1 of this embodiment,

(1) the LED light source 2, the heat sink 3, the electric fan unit 4, the driver circuit 5, and the attachment 6, all of which are constituent elements of the LED light source module 1, are integrated,

(2) the structure of the portion 6A1 of the attachment main body 6A fitted into the light source mounting hole 54 has the same structure as that of the attachment portion of the halo ^¬ gen bulb (light source module) 60,

(3) the LED light source 2, the heat sink 3, the electric fan unit 4, and the driver circuit 5 are designed such that they are all within the projection plane viewed in the insertion direction of the portion 6A1 into the light source mounting hole 54, and

(4) the sizes, shapes, and arrangements of these constituent elements are selected such that the LED light source 2 is ac- curately located and arranged with respect to the reflecting surface 52a of the reflector 52.

[0028] The LED light source module 1 can replace a halogen bulb. The use of the LED light source module 1 instead of the halogen bulb can realize the LED head light. [0029] When the LED light source module 1 needs replacement, unlike the conventional case where the whole head light is replaced, only the LED light source module 1 can be replaced. Further, the LED light source module 1, which is simple in configuration, can be provided at low costs.

[0030] Therefore, by using the LED light source module 1 as a light source of a head light, costs can be significantly re- duced compared to the conventional LED head light in which only a light source portion using an LED cannot be replaced. Further, since the light source portion is detachable, main ^¬ tainability of the LED head light can be significantly im ^¬ proved. The LED light source module 1 can be distributed in a market where it is sold as a portion of a vehicle equipped with an LED head light as well as as a replacement part of a vehicle having been sold. Further, the LED light source mod ^¬ ule 1 can be used as a head light not only for a four-wheel vehicle but also for a two-wheel vehicle. [0031] Further, the LED light source module 1 does not need a heat exhausting system separately since it has the heat sink 3 for removing heat from the LED light source 2 and the elec ^¬ tric fan unit 4 for cooling the heat sink 3 as means for forcibly cooling the LED light source 2. The electric fan unit 4 can maintain the junction temperature of the LED light source 2 having an emission performance of 350 lm or more at or below a reference temperature (about 150°C) at which the LED light source 2 can operate stably. Accordingly, the LED light source module 1, although replaceable, can provide an emission performance of 350 lm or more which is required per head light with a single module.

[0032] Further, in this embodiment,

(5) the heat sink 3 and the driver circuit 5 are provided ad ^¬ jacent to each other, and

(6) the heat sink 3 is structurally designed such that the air supplied from the electric fan unit 4 to the heat sink 3 can be guided to the driver circuit 5. With this configuration, the air supplied from the electric fan unit 4 can be utilized effectively to cool the LED light source 2 as well as the driver circuit 5. Cooling the driver circuit 5 allows employing such a simple and inexpensive cir- cuit configuration as a linear IC or resistance bridge.

[0033] With the LED light source module 1, the amount of light of at least 350 lm required per head light of a vehicle can be satisfied by a single light source module. Therefore, it is not necessary to combine a plurality of light source modules in designing a head light so as to satisfy the re ^¬ quired amount of light. Using the LED light source module 1 as a general-purpose light source for a head light eliminates the need for individually designing head lights depending on types of vehicles. [0034]

[Second Embodiment]

FIG. 9 shows a second embodiment of the LED light source mod ^¬ ule of the present invention. An LED light source 21 of an LED light source module 11 shown in FIG. 9 has a substrate 22 joined to the heat sink 3. The substrate 22 is formed of a material excellent in thermal conductivity, such as aluminum alloy, carbon material, molybdenum, copper, or silver. The substrate 22 has a first mounting surface 23-1 and a second mounting surface 23-2. The first mounting surface 23-1 and the second mounting surface 23-2 are different from each other in distance from the heat sink 3. The anteriorly- located first mounting surface 23-1 is formed shorter than the second mounting surface 23-2. A first LED chip 24-1 is mounted on the first mounting surface 23-1. A second LED chip 24-2 is mounted on the second mounting surface 23-2.

One of the first LED chip 24-1 and the second LED chip 24-2 is an LED chip for producing high beam, and the other is for low beam. The first and second LED chips 24-1 and 24-2 are each composed of a single or a plurality of light-emitting elements .

[0035]

[Third Embodiment]

FIG. 10 shows a third embodiment of the LED light source mod ^¬ ule according to the present invention.

An LED light source 31 of an LED light source module 12 shown in FIG. 10 has a substrate 33 joined to the heat sink 3. The substrate 33 is formed of a material excellent in thermal conductivity, such as aluminum alloy, carbon material, molyb ^¬ denum, copper, or silver. The substrate 33 has a first mounting surface 33-1 and a second mounting surface 33-2. The first mounting surface 33-1 and the second mounting surface 33-2 are inclined toward each other to constitute a triangu ^¬ lar roof-shaped mounting surface including a boundary between the ridge lines. A first LED chip 34-1 is mounted on the first mounting surface 33-1. A second LED chip 34-2 is mounted on the second mounting surface 33-2. One of the first LED chip 34-1 and the second LED chip 34-2 is an LED chip for producing high beam, and the other is for low beam. The first and second LED chips 34-1 and 34-2 are each composed of a single or a plurality of light-emitting elements.

[0036]

[Fourth Embodiment]

FIG. 11 shows a fourth embodiment of the LED light source mo ^¬ dule according to the present invention.

An LED light source module 13 shown in FIG. 11 includes first and second heat sinks 3-1 and 3-2 disposed on both upper and lower sides of the electric fan unit 4. A first LED light source 2-1 is directly mounted on the first heat sink 3-1, and a second LED light source 2-2 is directly mounted on the second heat sink 3-2. One of the first LED chip 2-1 and the second LED chip 2-2 is a light source for producing high beam, and the other is for low beam.

[0037]

[Fifth Embodiment]

FIG. 12 shows a fifth embodiment of the LED light source mod ^¬ ule according to the present invention.

An LED light source 41 of an LED light source module 14 shown in FIG. 12 has a substrate 43 joined to the heat sink 3. The substrate 43 is formed of a material excellent in thermal conductivity, such as aluminum alloy, carbon material, molyb ^¬ denum, copper, or silver. The substrate 43 has a first mounting surface 43-1 and a second mounting surface 43-2. The first mounting surface 43-1 and the second mounting surface 43-2 are different from each other in distance from the heat sink 3. The anteriorly-located first mounting surface 43-1 is formed taller than the second mounting surface 43-2. A first LED chip 44-1 is mounted on the first mounting surface 43-1. A second LED chip 44-2 is mounted on the second mounting sur- face 43-2. One of the first LED chip 44-1 and the second LED chip 44-2 is an LED chip for producing high beam, and the other is for low beam. The first and second LED chips 44-1 and 44-2 are each composed of a single or a plurality of light-emitting elements. [0038] An upper side portion of a head light 81 shown in FIG. 12 is composed of an inner frame 82 and an opaque outer cover 83 covering a portion ahead of the inner frame 82. A reflector 84 is curved in the shape of a concave sphere and extends forward from a lower end of the inner frame 82. A light emitting opening 85 is defined between a front end of the re ^¬ flector 84 and the outer cover 83, and a transparent lens 86 is attached to the light emitting opening 85. The LED light source module 14 is attached to the head light 81 with the first LED chip 44-1 and the second LED chip 44-2 oriented downward, i.e., facing the reflector 84. The heat sink 3 and the electric fan unit 4 are invisible from the outside of the head light 81 since they are located behind the outer cover 83.

[0039] The present invention is not limited to the above- described embodiments, and the shapes or sizes of the respec ^¬ tive portions, or specific configurations of the respective elements can be changed appropriately. For example, the abo ^¬ ve-described embodiments show that the shape of the flat pla ^¬ te portion 3a of the heat sink 3 is roughly square, but it is not limited to such a shape but may be rectangular or circu ^¬ lar. Further, the stacking direction of the LED light source 2, the heat sink 3, and the electric fan unit 4 may be an in ^¬ sertion direction of the attachment main body 6A into the light source mounting hole 54. In this case, the LED light source 2 is provided to directly face the light emitting ope ^¬ ning 53 of the head light 81. An LED light source module 15 illustrated in FIGS. 13 to 15 includes the electric fan unit 4 and the driver circuit 5 inside the attachment main body 6A. The shape of the flat plate portion 3a of the heat sink 3 is hexagonal. The side plate portion 3c is provided along four of six sides of the flat plate portion 3a. An air blasting port 6A3 and air intake ports 6A4 are formed in a front end 6A2 of the attachment main body 6A. The air blast ^¬ ing port 6A3 is formed in a central portion of the front end 6A2 of the attachment main body 6A. The electric fan unit 4 is attached to the air blasting port 6A3. The air intake ports 6A4 are provided in an arc shape along a peripheral edge of the front end 6A2 of the attachment main body 6A. When the electric fan unit 4 is driven, air in the lighting chamber 56 flows from the air intake ports 6A4 into the at- tachment main body 6A. After being used to cool the driver circuit 5, the air flows into the heat sink 3 through the air blasting port 6A3. This air cools the heat sink 3 as well as the LED light source 2 via the heat sink 3.

Additionally, in the above-described embodiments, only re- placeability with a halogen bulb has been described, but it is possible to provide replaceability with an HID bulb or other light bulbs as long as the attachment structure is re ^¬ placeable .

Further, in the above-described embodiments, the example whe ^¬ re the LED light source module of the present invention is applied to the light source of the head light has been de ^¬ scribed, but the LED light source module of the present in ^¬ vention can be applied also as a light source for a signal light.

The LED chips may be super luminescent diode chips or solid state light emitters with a quasi-monochromatic emission spectrum (for example emitting a color like red, green, blue, or radiation in the Ultraviolet or Infrared wavelength range) or solid state light emitters with white light emission due to phosphor converted excitation radiation radiated by the LED chips. Each LED chip may emit an individual color or ra ^¬ diation spectrum. Direct emitting LED chips without phosphor conversion and LED chips that employ phosphor-conversion may be used in various combinations and geometrical arrangements. A primary optic component (such as a lens or a collimation unit) may be attached to an LED chip or placed in front of an LED chip in order to shape the characteristics of the LED emission pattern. The LED chips may employ a joint primary optic.

The LED chips may be operated individually and/or operated grouped in arrangements containing a certain number of LED chips, or jointly altogether. The LED chips may be operated with different current levels and therefore different power levels and different radiation output.

The meaning of the term "LED" used in the description and claims is not restricted to light emitting diodes but also includes laser diodes and organic light emitting diodes

(OLED) like Polymer organic light emitting diodes for example .

The lighting apparatus with the LED light source module ac ^¬ cording to the invention may be used for lighting purposes

(for example headlighting, rear lighting, auxiliary lighting) for cars, trucks, buses, trains, bicycle, electrical bikes

(E-Bikes), Trikes, Quads, on-road or off-road vehicles, elec ^¬ trically assisted wheelchairs, marine lighting, positional lighting, aeroplanes, helicopter, ships, and marine vessels. Furthermore, the LED light source module according to the in ^¬ vention may be used in a projection apparatus for entertainment purposes for example or in underwater lights, street lights, mining lights or in fixtures for general lighting.

, _n

[Description of Reference Numerals]

[0040]

1 LED light source module

2 LED light source

2a LED chip

2b LED supporting portion

2-1 First LED light source

2-2 Second LED light source

3 Heat sink

3a Flat plate portion

3b Fin

3c Side plate portion

3-1 First heat sink

3-2 Second heat sink

4 Electric fan unit

4b Casing body

4a Fan

5 Driver circuit

6 Attachment

6A Attachment main body

6B Supporting frame

11 LED light source module

12 LED light source module

13 LED light source module

14 LED light source module

15 LED light source module

21 LED light source

22 Substrate

23- 1 First mounting surface

23- 2 Second mounting surface

24- 1 First LED chip

24- 2 Second LED chip

31 LED light source

33 Substrate , _ i y

33- 1 First mounting surface

33- 2 Second mounting surface

34- 1 First LED chip

34- 2 Second LED chip

41 LED light source

43 Substrate

43- 1 First mounting surface

43- 2 Second mounting surface

44- 1 First LED chip

44- 2 Second LED chip

51 Head light

52 Reflector

52a Reflecting surface

53 Light emitting opening

54 Light source mounting hole

55 Lens