JP5033559B2 - LED lamp unit - Google Patents

Description

  The present invention relates to an LED lamp unit using an LED as a light source.

  The LED has a characteristic that the light emission efficiency decreases as the temperature rises. Possible causes of LED temperature rise include self-heating during lighting and exposure to a high temperature environment.

  On the other hand, LEDs generally have advantages such as small size, low power consumption, and long life compared to various lamps. Conventionally, LEDs have been used to make high-mount stop lamps, stop-and-tail lamps, turn signals, etc. In recent years, a vehicle headlamp using an LED as a light source has been proposed.

  Some headlamps using LEDs as light sources include, for example, a lamp chamber formed by a front lens and a housing, and an LED lamp unit using LEDs as a light source is supported in the lamp chamber. In this case, the LED lamp unit needs to drive the LED as a light source with high power in order to secure the amount of irradiation light necessary as a headlamp, the use environment temperature is high in a sealed lamp room, etc. Therefore, the LED is often used at the limit value of the junction temperature.

  Then, the temperature of the LED itself increases due to the self-heating of the LED and the environmental temperature (ambient temperature). As a result, the light emission efficiency of the LED decreases, the amount of light emitted from the lamp decreases, and the light distribution performance deteriorates. In some cases, the light distribution standard required for the lamp may not be satisfied.

  Therefore, for the purpose of suppressing the occurrence of the above problem, it has been proposed that the LED lamp unit supported in the lamp chamber be configured as shown in FIG. The LED lamp unit 50 has a projector-type unit structure, and its constituent members are an upper reflector 52 having a reflecting surface 51 based on an ellipse, a lower reflector 54 in which a shade 53 is integrally formed, It includes a projection lens 55 that forms a predetermined light distribution pattern, an LED mounting substrate 57 on which an LED light source 56 is mounted, a heat sink member 60 that includes a mounting surface 58 and a heat radiating portion 59.

  The LED mounting substrate 57 is placed on the mounting surface 58 of the heat sink member 60 via an insulating heat conductive film, and the upper reflector 52 and the lower reflector 54 are also mounted so as to cover the LED mounting substrate 57. The projection lens 55 is held at the opening edge formed by the upper reflector 52 and the lower reflector 54.

  In the LED lamp unit 50 having the above configuration, when power is supplied to the LED light source 56 to light it, the light emitted from the LED light source 56 toward the reflection surface 51 of the upper reflector 52 is reflected by the reflection surface 51 and reflected. Part of the light is cut off (light-shielded) by a shade 53 integrally formed with the lower reflector 54, and the remaining reflected light that has passed through the shade 53 is guided through the projection lens 55 to have a predetermined arrangement having a cut-off line. The light pattern is irradiated outside the LED lamp unit 50.

  At this time, the heat generated when the LED light source 56 is turned on is transferred from the mounting surface 58 of the heat sink member 60 to the heat radiating portion 59 via the LED mounting substrate 57 and the insulating heat conductive film, and moves from the heat radiating portion 59 to the LED. It is diffused out of the lamp unit 50 and the temperature rise of the LED light source 56 is suppressed (for example, refer to Patent Document 1).

  A headlamp unit 80 configured as shown in FIG. 13 has also been proposed. The projection lens 81, the shade 82, and the LED light source 83 are sequentially arranged along the optical axis Z from the front, and the reflector 84 that reflects the light emitted from the LED light source 83 forwards the LED light source 83. It is arrange | positioned so that it may cover.

  Further, a T-shaped mounting plate 85 comprising a horizontal plate 85a and a vertical plate 85b is provided, and one LED 86, 87 is mounted on each side of the horizontal plate 85a, and the front and rear surfaces of the vertical plate 85b. A heat sink member 88 is attached to the sub assembly 89.

The heat generated when the LEDs 86 and 87 are turned on moves to the horizontal plate 85a of the mounting plate 85, is transferred through the horizontal plate 85a to the vertical plate 85b, and is transferred through the vertical plate 85b to the heat radiating member 88. Then, the heat is dissipated from the heat radiating member 88 to the outside of the headlamp unit 80, and the temperature rise of the LEDs 86 and 87 is suppressed (see, for example, Patent Document 2).
JP 2007-109613 A JP 2006-107875 A

  The LED lamp unit 50 proposed in the above-mentioned “Japanese Unexamined Patent Application Publication No. 2007-109613” includes a mounting surface 58 and a heat radiating portion 59, an upper reflector 52, a lower reflector 54, and a projection lens 55 in which the LED light source 56 constitutes the heat sink member 60. The heat generation of the LED light source 56 is dissipated from the heat radiation part 59 of the heat sink member 60 to the outside of the LED lamp unit 50, and at the same time, the mounting surface 58 of the heat sink member 60. To the sealed space 61 containing the LED light source 56.

  Therefore, the heat trapped in the sealed space 61 raises the ambient temperature of the LED light source 56, and the heat dissipation effect by the heat sink member 60 is reduced, and the suppression of the temperature rise of the LED light source 56 is hindered.

  Further, the headlamp unit 80 proposed in the above-mentioned “Japanese Patent Laid-Open No. 2006-107875” conducts the horizontal plate 85a having a high heat conduction resistance until the heat generated by the LEDs 86 and 87 is conducted to the heat radiating member 88. Therefore, the heat conduction efficiency is poor before reaching the heat radiating member 88, so that the heat radiating effect is reduced and the suppression of the temperature rise of the LEDs 86 and 87 is hindered.

  Therefore, the present invention was devised in view of the above problems, and the object of the present invention is to suppress the temperature rise of the LED light source by making the LED lamp unit with the LED a light source having a high heat dissipation structure, Accordingly, an object of the present invention is to provide an LED lamp unit in which a decrease in light emission efficiency of the LED is suppressed and a predetermined amount of irradiation light can be secured.

In order to solve the above-mentioned problems, an invention described in claim 1 of the present invention includes an LED light source, a heat sink for mounting the LED light source, and dissipating heat generated when the LED light source is turned on to the outside. An LED lamp unit that is disposed so as to cover the LED light source and reflects the light emitted from the LED light source toward the front, wherein the LED lamp unit is the heat sink of the LED lamp unit. The heat sink is integrated with a base portion on which the LED light source is mounted and a plurality of fin portions, and the base portion is located below the irradiation axis of the LED lamp unit toward the rear. The LED light source is mounted on the surface on the side facing the reflector, on the upper side of the inclined base portion, The portion of the base portion is formed by inclining backward from the surface opposite to the surface on which the LED light source is mounted, and at a position corresponding to the base portion on which the LED light source is located. The formed LED light source side fin portion, and the base portion which is formed to be inclined rearward and upward from a surface opposite to the surface on which the LED light source is mounted of the base portion, and below the LED light source A fin portion on the side away from the LED light source formed at a position corresponding to the portion, and a fin on the side away from the LED light source located rearward with respect to the length of the LED light source side fin portion located in front The length of the part is longer, and the area of the fin part on the side farther from the LED light source is larger than that of the LED light source side fin part .

Moreover, the invention described in claim 2 of the present invention is the reflector according to claim 1, wherein the reflector includes a reflector fixing portion at the rear, and a fin portion on the side away from the LED light source is formed in the reflector fixing portion. The base portion is connected .

Further, in the invention described in claim 3 of the present invention, in claim 2 , the base portion includes a front side facing the reflector and a rear side connected to the reflector fixing portion, and the front side is on the rear side. It is characterized by being shorter than that .

  The LED lamp unit of the present invention is provided with a heat sink for dissipating heat generated when the LED light source is turned on to the outside, and the heat sink is positioned on the upper side when the LED lamp unit is mounted on a vehicle.

  As a result, the heat generated from the LED light source is efficiently dissipated to the outside, so that the temperature rise of the LED light source is suppressed by high heat dissipation performance, and thus the decrease in the light emission efficiency of the LED light source is suppressed and a predetermined amount of light is secured. An LED lamp unit that can be used has been realized.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 11 (the same parts are given the same reference numerals). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  FIG. 1 is a schematic cross-sectional view of Embodiment 1 relating to an LED lamp unit of the present invention. In the following figures, the upward direction in the drawing is the upward direction of the vehicle, the downward direction in the drawing is the downward direction of the vehicle, the left direction in the drawing is the forward direction of the vehicle, and the right direction in the drawing is the backward direction of the vehicle. The state in which the LED lamp unit is mounted in the vehicle (direction) is shown.

  The LED lamp unit 1 includes an LED light source 2, an LED mounting substrate 3 on which the LED light source 2 is mounted, a heat sink 4 on which the LED mounting substrate 3 is placed via an insulating heat conductive sheet (not shown), and a heat sink 4 fixed. The reflector 5, the lens holder 6 connected to the reflector 5, and the inner surface of the reflector 5 opposite to the heat sink 4 on the lens holder 6 side (lower side) are extended toward the heat sink 4 side (upper side). The projector 7 includes a projection lens 8 held by a shutter 7 and a lens holder 6, and constitutes a projector-type LED lamp unit 1.

  The heat sink 4, the reflector 5, the lens holder 6, and the projection lens 8 form a closed space 9, and an optical system that controls the optical path of light emitted from the LED light source 2 is configured in the closed space 9.

  Among them, the LED light source 2 is a light source that emits white light or light of a color tone close to white light by a combination of a blue LED element that emits blue light or an ultraviolet LED element that emits ultraviolet light and a phosphor.

  For example, when the LED element is a blue LED element, by using a phosphor that is wavelength-converted into yellow light that is excited by blue light and has a blue complementary color, a part of the blue light emitted from the blue LED element is phosphor. Can be generated by additive color mixing of the yellow light wavelength-converted by exciting the blue light and the blue light emitted from the blue LED element.

  Similarly, when the LED element is a blue LED element, it is emitted from the blue LED element by using a mixture of two types of phosphors that are excited by blue light and wavelength-converted into green light and red light, respectively. It is also possible to generate white light by additive color mixing of green light and red light whose wavelengths are converted by exciting a phosphor with a part of blue light and blue light emitted from a blue LED element.

  On the other hand, when the LED element is an ultraviolet LED element, it is emitted from the ultraviolet LED element by using a mixture of three types of phosphors that are excited by ultraviolet light and convert wavelengths of blue light, green light, and red light, respectively. White light can also be generated by additive color mixing of blue light, green light, and red light whose wavelengths are converted by exciting the phosphor with the ultraviolet light.

  Furthermore, light of various color tones other than white light can be generated by appropriately combining the color tone of the light emitted from the LED element and the phosphor.

  The heat sink 4 includes a base portion 4a and a fin portion 4b. The base portion 4a has a plate shape with a constant thickness, and the plane thereof is positioned substantially parallel to the irradiation axis X of the lamp unit 1. The fin portion 4b has a plurality of plate-like fins arranged in parallel upward on the surface of the base portion 4a opposite to the surface on which the LED mounting substrate 3 is placed, and the fin portion 4b Both lateral end portions 4ba extend substantially perpendicular to the base portion 4a, and a tip portion 4bb on the side facing the base portion 4a extends substantially parallel to the base portion 4a. The heat sink 4 is made of a material having good thermal conductivity, and is made of any one of metals such as Al, Al alloy, Cu, and Cu alloy.

  However, the heat sink 4 is manufactured by a method such as casting, brazing or caulking. When the fin portion 4b is retrofitted to the base portion 4a by a method such as brazing or caulking, the fin portion 4b is made of a material different from that of the base portion 4a. It can be a corrugated fin or a plate fin.

  The reflector 5 has a shutter 7 that extends upward from the inner bottom surface of the reflector 5 on the lens holder 6 side. Like the heat sink 4, any one of Al, Al alloy, Cu, Cu alloy, and the like can be used. It can be formed of any of these metals, or can be formed of a resin material. In any case, the reflector 5 is composed of three regions having the inner peripheral surface as a reflecting surface.

  Among them, the first reflector region 5a is an ellipse having the vicinity of the LED light source 2 as the position of the first focus F1 and the vicinity of the upper end portion 7a of the shutter 7 as the position of the second focus F2 so as to cover the LED light source 2. The inner peripheral surface is a system surface, and the inner peripheral surface is an elliptical reflective surface 5aa. The long axis including the first focal point F1 and the second focal point F2 is located substantially on the same straight line as the irradiation axis X of the lamp unit 1.

  The second reflector region 5b has the vicinity of the LED light source 2 as the position of the first focal point F1 so as to cover the LED light source 2 in the same manner as the first reflector region 5a, and the inner surface of the third reflector region 5c. It has an inner peripheral surface made of an elliptical surface with the position in the vicinity of the first focal point F3 as the position of the second focal point, and the inner peripheral surface is an elliptical reflecting surface 5bb.

  In the third reflector region 5c, the position near the second focus F3 on the inner peripheral surface of the second reflector region 5b is set as the position of the first focus, and the vicinity of the upper end 7a of the shutter 7 is set as the second focus F2. The inner peripheral surface is an elliptical surface, and the inner peripheral surface is an elliptical reflecting surface 5cc.

  Therefore, the shutter 7 is positioned between the elliptical reflecting surfaces 5aa, 5bb, 5cc of the reflector 5 and the projection lens 8, and the upper end 7a forms a cut-off line of the irradiation beam from the LED lamp unit 1.

  The lens holder 6 has a substantially cylindrical shape, and holds the projection lens 8 in the opening on the irradiation direction side.

  The projection lens 8 is composed of a convex lens that swells at least in the irradiation direction.

  In the lamp unit 1 having the above configuration, the LED light source 2 at the position of the first focal point F1 is turned on, and the light emitted from the LED light source 2 toward the elliptical reflecting surface 5aa of the first reflector region 5a. Is reflected by the elliptical reflecting surface 5aa and the reflected light is in the direction of the upper end 7a of the shutter 7 at the position of the second focal point F2, and a part of the light path is blocked by the shutter 7.

  On the other hand, of the light reflected by the elliptical reflecting surface 5aa of the first reflector region 5a, the reflected light that is not blocked by the shutter 7 is propagated through the lens holder 6 and reaches the projection lens 8.

  The light emitted from the LED light source 2 at the position of the first focal point F1 toward the elliptical reflecting surface 5bb of the second reflector region 5b is reflected by the elliptical reflecting surface 5bb, and the reflected light is reflected. It goes in the direction of the second focal point F3. The second focal point F3 is also the first focal point of the third reflector 5c, and the reflected light directed in the direction of the focal point F3 is reflected again by the elliptical reflecting surface 5cc of the third reflector region 5c, and the reflected light is reflected. Heading toward the vicinity of the upper end 7a of the shutter 7 at the position of the second focal point F2, a part of the light path is blocked by the shutter 7.

  On the other hand, the reflected light not blocked by the shutter 7 out of the light reflected by the elliptical reflecting surface 5cc of the third reflector region 5c is propagated through the lens holder 6 and reaches the projection lens 8.

  In this way, the light emitted from the LED light source 2 and reflected once by the elliptical reflection surface 5aa to reach the projection lens 8 and the light emitted from the LED light source 2 by the elliptical reflection surface 5bb and the elliptical reflection surface 5cc are 2 All of the light that has been reflected back and reaches the projection lens 8 is guided through the projection lens 8 and irradiated outside the LED lamp unit 1 with a predetermined light distribution pattern having a cutoff line while being focused.

  At the same time, when the LED light source 2 is turned on, the LED light source 2 generates heat. As shown in FIG. 2, this heat passes through the LED mounting substrate 3 on which the LED light source 2 is mounted and the insulating heat conductive sheet. The mounting substrate 3 is placed and transferred to the plate-like base portion 4a of the heat sink 4 and moved, and the heat moved to the base portion 4a is further changed to the surface of the base portion 4a on which the LED mounting substrate 3 is placed. It is conducted and moved to the fin portion 4b composed of a plurality of plate-like fins arranged in parallel upward on the opposite surface, and is diffused to the outside from the fin portion 4b.

  At this time, since the base portion 4a and the fin portion 4b of the heat sink 4 are both located above the LED light source 2, the heat generated by the LED light source 2 is sequentially and smoothly transferred with high heat conduction efficiency. It is conducted to the part 4b, moves, and is dissipated out of the LED lamp unit 1 along the upward convection flow from the fin part 4b, and is dissipated in the closed space 9 in which the LED light source 2 is accommodated. rare.

  As a result, the temperature rise of the LED light source is suppressed by the high heat dissipation performance, and thus the decrease in the light emission efficiency of the LED light source is suppressed, and it becomes possible to secure a predetermined amount of irradiation light.

  FIG. 3 is a schematic sectional view of the second embodiment. The second embodiment is different from the first embodiment in the shape of the fin portion 4b of the heat sink 4, the arrangement direction of the heat sink 4, and the shape of the reflector 5.

  Specifically, the reflector fixing portion 5 d that fixes the heat sink 4 of the reflector 5 is inclined downward with respect to the irradiation axis X of the lamp unit 1.

  Therefore, the base portion 4 a of the heat sink 4 and the LED mounting substrate 3 placed on the base portion 4 a are also inclined downward with respect to the irradiation axis X of the LED lamp unit 1.

  The fin part 4b of the heat sink 4 is divided into two, and the length of the fin part 4d located rearward is longer than the length of the fin part 4c located forward. Both lateral end portions 4ba of the fin portion 4b including the fin portions 4c and 4d extend substantially perpendicular to the base portion 4a, and tip portions 4cb and 4db of the fin portions 4c and 4d on the side facing the base portion 4a. Extends substantially parallel to the base portion 4a.

  A space 10 surrounded by the heat sink 4, the reflector 5, the lens holder 6, and the projection lens 8 is connected to the outside of the lamp unit 1 by a gap 11 between the heat sink 4 and the third reflector region 5 c of the reflector 5.

  Therefore, the heat generated in the LED light source 2 is generated by the plate-like base portion of the heat sink 4 on which the LED mounting substrate 3 is mounted via the LED mounting substrate 3 on which the LED light source 2 is mounted and the insulating heat conductive sheet. The heat transferred to the base portion 4a is further transferred to the surface of the base portion 4a opposite to the surface on which the LED mounting substrate 3 is placed. Conducted and moved by the fin portions 4c and 4d made of plate-like fins and diffused to the outside from the fin portions 4c and 4d.

  At this time, the fin portion 4c in which the LED mounting substrate 3 is located below and the fin 4d in which the connection portion to the reflector fixing portion 5d of the reflector 5 is located below are both inclined upward and backward. The area of each fin is larger in the fin portion 4d than in 4c.

  Therefore, the heat generated by the LED light source 2 and transferred to the base portion 4a of the heat sink 4 is transferred to the fin portion 4c and the fin portion 4d to move, but the amount of heat to be moved is larger than that of the fin 4c. Is more, and a heat flow from the fin portion 4c toward the fin portion 4d is formed.

  Further, since the base portion 4a of the heat sink 4 is inclined, the heat dissipated to the outside from the fin portion 4c side of the heat sink 4 is directed to the fin portion 4d side, and from the side opposite to the fin portion 4c side of the fin portion 4d. An upward convection is also formed.

  Therefore, a convection heading upward from the fin portion 4d located far from the LED lamp unit 1 is formed, and the heat sink is formed from the gap 11 formed by the third reflector region 5c of the reflector 5 and the heat sink 4 that is not in the convection flow path. 4, little heat enters the space 10 surrounded by the reflector 5, the lens holder 6 and the projection lens 8, and the heat radiation effect of the LED light source 2 located in the space 10 is hardly lowered.

  As a result, similar to the first embodiment, the temperature rise of the LED light source is suppressed by the high heat dissipation performance, and thus the decrease in the light emission efficiency of the LED light source is suppressed, and a predetermined irradiation light amount can be secured.

  In particular, in the case of adopting the configuration of the second embodiment, the LED lamp unit 1 uses the second reflector region 5b and the third reflector region 5c to emit light having a high emission intensity that is emitted directly from the LED light source 2. Irradiation can be performed with a single reflection. Therefore, the light from the LED light source 2 can be used more efficiently than the LED lamp unit 1 of the first embodiment.

  In the first and second embodiments, the LED lamp unit 1 is a vehicle headlamp used for a passing beam, and thus the shutter 7 is provided near the focal point F2. However, the present invention is not limited to this. . That is, when the LED lamp unit 1 is used to form a traveling beam that does not need to block light from the light source, the shutter 7 is not provided near the focal point F2. With this configuration, the LED lamp unit 1 emits the light from the reflector 5 through the projection lens 8 as it is.

  Below, the simulation of the heat dissipation effect of the LED lamp unit of this invention and its result are demonstrated.

  As a representative of the present invention, the configuration of the LED lamp unit of Example 1 described above was adopted, and an LED lamp unit having the configuration shown in FIG. 4 was adopted as a comparative example. In the comparative example, as in Example 1, the LED light source 2, the LED mounting substrate 3 on which the LED light source 2 is mounted, and the heat sink 4 on which the LED mounting substrate 3 is placed via an insulating heat conductive sheet (not shown). , The reflector 5 to which the heat sink 4 is fixed, the lens holder 6 connected to the reflector 5, the inner peripheral surface of the heat sink 4 side (lower side) on the lens holder 6 side of the reflector 5 toward the opposite side (upper side) of the heat sink 4. The projector-type LED lamp unit 1 includes a shutter 7 that is extended and a projection lens 8 that is held by a lens holder 6.

  The difference between the first embodiment and the comparative example is that the position of the heat sink 4 is different. The heat sink 4 of the first embodiment is located on the upper side with respect to the irradiation axis X of the LED lamp unit 1, whereas the comparative example is below the irradiation axis X. Located on the side. That is, the comparative example has a configuration in which the shutter 7 is provided on the inner peripheral surface on the lower side of the reflector 5 by inverting the first embodiment upside down.

  The simulation setting conditions are as follows: both the dimensions of the base portion 4a of the heat sink 4 are 60 mm × 60 mm, the height of each fin of the fin portion 4b is 30 mm, the power supplied to the LED light source 2 is 10 W, and the ambient temperature Was set to 60 ° C.

  5 to 10 show simulation results, and FIG. 5 shows isothermal lines on the surface on which the LED mounting substrate 3 of the base portion 4a of the heat sink 4 is placed in the comparative example. 7 represents the temperature distribution on each straight line of a plurality of straight lines parallel to the X direction (longitudinal direction) set at a predetermined interval in the Y direction (short direction) of the same surface. It shows the temperature distribution on each straight line of a plurality of straight lines parallel to the Y direction (short direction) set at a predetermined interval in the X direction (longitudinal direction) of the same surface.

  8 shows isothermal lines on the surface of the base portion 4a of the heat sink 4 on which the LED mounting substrate 3 is placed in Example 1, and FIG. 9 shows the same surface in the Y direction (short direction). FIG. 10 shows a temperature distribution on each of a plurality of straight lines parallel to the X direction (longitudinal direction) set at a predetermined interval. FIG. 10 shows a predetermined surface in the X direction (longitudinal direction) of the same surface. It represents the temperature distribution on each of a plurality of straight lines parallel to the Y direction (short direction) set at intervals.

  6 and FIG. 7, the comparative example has a temperature of 112 ° C. immediately below the LED light source 2, and FIG. 9 and FIG. Under the conditions, it was confirmed that the temperature at the position immediately below the LED light source 2 of Example 1 was reduced by about 6 ° C. relative to the comparative example.

  By the way, the LED light source used in the comparative example and Example 1 has the temperature dependence of the luminous flux as shown in FIG. 11, and the luminous flux when the temperature of the LED light source is 50 ° C. is 100%. The relative luminous flux at 106 ° C is about 85%, the relative luminous flux at 112 ° C is about 83%, and the relative luminous flux at 106 ° C is about 2% higher than at 112 ° C. Will do.

  Accordingly, assuming that the temperature of the LED light source 2 is as close as possible to the temperature immediately below the LED light source 2 on the surface of the base portion 4a of the heat sink 4 on which the LED mounting substrate 3 is placed, the LED light source is compared with the comparative example. It can be seen that the heat dissipation effect of Example 1 in which the temperature was reduced by about 6 ° C. contributed to an improvement of 2% of the luminous flux.

  In addition, some LED light sources have a characteristic that the lifetime is halved when the temperature rises by 10 ° C. depending on the material, and the fact that the temperature rise of the LED light source can be suppressed by 6 ° C. according to the present invention also leads to an improvement in reliability by extending the lifetime. Is.

  As described above, when the LED lamp unit of the present invention is mounted on a vehicle, the heat sink on which the LED light source is placed is arranged so as to be positioned above the LED lamp unit, and the heat generated by the LED light source is efficiently obtained. Heat was dissipated with a heat sink.

  As a result, the temperature rise of the LED light source is suppressed by the high heat dissipation performance, and therefore, the decrease in the light emission efficiency of the LED light source is suppressed, and it is possible to secure a predetermined irradiation light amount. .

It is a schematic sectional drawing of Example 1 concerning this invention. It is a general | schematic fragmentary sectional view of Example 1 concerning this invention. It is a schematic sectional drawing of Example 2 concerning this invention. It is a schematic sectional drawing of a comparative example. It is an isotherm figure of a comparative example. It is a temperature distribution figure of a comparative example. Similarly, it is a temperature distribution figure of a comparative example. 3 is an isothermal diagram of Example 1. FIG. 2 is a temperature distribution diagram of Example 1. FIG. Similarly, it is the temperature distribution figure of Example 1. FIG. It is a graph which shows the temperature dependence of the emitted light beam of a LED light source. It is a schematic sectional drawing of a prior art example. It is a schematic sectional drawing of another prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 LED lamp unit 2 LED light source 3 LED mounting board 4 Heat sink 4a Base part 4b Fin part 4ba Horizontal end part 4bb Tip part 4c Fin part 4cb Tip part 4d Fin part 4db Tip part 5 Reflector 5a 1st reflector area | region 5aa Elliptical reflection Surface 5b Second reflector region 5bb Elliptic reflection surface 5c Third reflector region 5cc Elliptic reflection surface 5d Reflector fixing portion 6 Lens holder 7 Shutter 7a Upper end portion 8 Projection lens 9 Closed space 10 Space 11 Gap

Claims (3)

An LED light source, a heat sink for mounting the LED light source and dissipating heat generated when the LED light source is turned on, and light emitted from the LED light source disposed so as to cover the LED light source forward An LED lamp unit having a reflector that reflects toward the
The LED lamp unit is mounted with the heat sink side of the LED lamp unit facing upward, and the heat sink has a base portion on which the LED light source is mounted and a plurality of fin portions, and the base portion is an LED lamp. The LED light source is mounted at a position on the upper side of the inclined base portion on the surface facing the reflector, and tilted downward with respect to the irradiation axis of the unit. The portion is formed so as to incline backward from the surface opposite to the surface on which the LED light source is mounted of the base portion, and is formed at a position corresponding to the base portion where the LED light source is located. The LED light source side fin portion and the surface of the base portion opposite to the surface on which the LED light source is mounted are inclined upward and rearward. The LED that is provided rearward with respect to the length of the LED light source side fin portion that is provided in the front side, including a fin portion on the side away from the LED light source that is formed at a position corresponding to the base portion below the LED light source The length of the fin part on the side away from the light source is longer, and the area of the fin part on the side away from the LED light source is larger than that of the LED light source side fin part. LED lamp unit. 2. The LED according to claim 1, wherein the reflector includes a reflector fixing portion on a rear side, and the base portion on which a fin portion on the side away from the LED light source is formed is connected to the reflector fixing portion. Lamp unit. The LED lamp unit according to claim 2 , wherein the base portion includes a front side facing the reflector and a rear side connected to the reflector fixing portion, and the front side is shorter than the rear side .

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