JP6131891B2 - Lighting fixtures and heat sinks - Google Patents

Description

  The present invention relates to a lighting fixture and a heat sink thereof.

  2. Description of the Related Art Lighting fixtures using light emitting elements such as LEDs (Light Emitting Diode) as light sources are widely used. When a light emitting element such as an LED becomes high temperature, the light emission efficiency is lowered and the lifetime is shortened. Therefore, it is necessary to pay sufficient attention to the heat dissipation surface when designing such a lighting fixture.

  Conventionally, in a lighting device such as a ceiling light for a high ceiling with a large luminous flux, the amount of heat generated by the LED is large, and the heat radiation fins are large, so that the heat radiation efficiency is deteriorated and the weight is increased. In order to make a shape with good heat dissipation efficiency, heat dissipation fins are often made with a good moldability such as aluminum die casting. However, aluminum die casting is disadvantageous in that it has a lower thermal conductivity than lumber such as aluminum.

  Patent Document 1 includes a heat radiating portion that radiates heat of a substrate on which a light emitting element is disposed from a heat radiating fin, and the heat radiating portion is configured by joining a pair of separable first heat radiating members to each other. There is disclosed a lighting fixture in which a concave portion forming an insertion hole through which a power cable is inserted is formed in at least one of the joining surfaces joined to each other of the first heat radiation member.

  In Patent Document 2, a light source is held so that light from the light source is emitted from a housing that houses the light source and an opening formed in the housing, and is fixed at a predetermined position in the housing. Formed on the top surface of the housing facing the heat radiating portion for dissipating heat generated from the heat sink, one or a plurality of vents formed in the heat radiating portion, and the heat radiating portion for fixing the light source at a predetermined position in the housing. In addition, an illumination device including one or a plurality of heat dissipation holes is disclosed.

  In Patent Document 3, the height dimension of the radiating fins is increased as the height dimension of the central part is small and the heights of the radiating fins are increased toward both ends of the plurality of radiating fins laminated at predetermined intervals. A luminaire with an air passage in between is disclosed.

  Patent Document 4 includes a base that faces a heating element and takes heat away from the heating element, and the heat resistance of the facing portion that faces the heating element in the base is higher than the thermal resistance of the surrounding portion that is the periphery of the facing portion. Is disclosed. The base has a heat receiving surface facing the heat generating body and a heat radiating surface facing the heat receiving surface, and the heat radiating surface includes a plurality of fins and is provided in a first region which is a region of the heat radiating surface corresponding to the facing portion. The thermal resistance of the fins is set higher than the thermal resistance of the fins provided in the second region, which is the region of the heat dissipation surface corresponding to the surrounding portion.

  Patent Document 5 discloses a technique for expanding the heat radiation area by embossing the heat radiation fin portion.

JP 2011-222433 A JP 2010-192180 A JP 2013-114413 A JP 2009-188329 A Utility Model Registration No. 3144103

  When the luminaire becomes a large luminous flux, it is necessary to increase the number of LEDs. Increasing the number of LEDs also increases the amount of heat generated. For example, when making a 400 W class large luminous flux module using a normal 1 W type surface mount type LED (100 lumen per one) as a light source, 400 LEDs must be mounted.

  In an appliance such as a high ceiling ceiling light with a large luminous flux, the heat generation amount of the LED is large and the heat sink is large. In particular, in a lighting fixture that does not use a fan as a cooling means, the heat dissipation efficiency and weight of the heat sink are problematic.

  As a basic configuration of the large luminous flux luminaire, a heat sink for heat radiation is provided on the back side of the LED light source, and an umbrella is provided as a dust guard and a light source reflecting member. In the lighting fixture having such a configuration, there is a problem in that the volume of the heat sink increases due to the large luminous flux of the lighting fixture, the heat dissipation efficiency decreases, and the weight increases. In addition, there is a problem that the temperature rises further due to the umbrella as a dust guard.

  The present invention has been made in order to solve the above-described problems, and an object thereof is to provide a lighting fixture capable of efficiently radiating heat and a heat sink thereof.

A lighting fixture according to the present invention includes a plate-like base portion , a heat sink having a plurality of radiating fins protruding from one surface side of the base portion, a light source portion disposed on the other surface side of the base portion, and an outer periphery of the heat sink. the cover, and an exterior having an upper exhaust port, comprising: a supporting member for supporting the heat sink inside the exterior, and which protrudes outward radiating fins of the outer edge of the base portion when viewed heat sink from the light source side, Air flows into the exterior of the exterior from the air intake port located below the heat radiating fin, the air is discharged from the air exhaust port , the plurality of heat radiating fins are arranged in parallel, and the support member is the surface of the radiating fin. The heat sink is supported from the side facing the surface .
In addition, a lighting fixture according to the present invention includes a heat sink having a plate-like base portion, a plurality of heat radiation fins protruding from one surface side of the base portion, a light source portion disposed on the other surface side of the base portion, and a heat sink. And an exterior having an exhaust port on the top, and when the heat sink is viewed from the light source unit side, the heat radiation fin projects outward from the outer edge of the base unit, and the air intake port located below the heat radiation fin The air flows into the exterior of the exterior, exhausts the air from the exhaust port, and the exterior has a frustum-shaped portion in which the cross-sectional area of the interior space cut by a plane parallel to the base portion decreases upward. The exhaust port has an opening on the upper surface of the frustum-shaped portion and does not open on the peripheral wall of the frustum-shaped portion.
The heat sink according to the present invention is a heat sink that has a plate-like base portion and a plurality of radiating fins protruding from one surface side of the base portion, and is used by arranging a light source portion on the other surface side of the base portion. At least a part of the plurality of radiating fins has a U-shaped shape having a concave portion on the side opposite to the base portion , and the U-shaped heat dissipation when the heat sink is viewed from the base portion side. Both ends of the fin project outward from the outer edge of the base, and the distance from the base to the recess is at least 1/2 of the length in the direction perpendicular to the base of the U-shaped radiating fin It is.
The heat sink according to the present invention includes a plate-like base portion, outer fins arranged radially on one surface side of the base portion, and a position closer to the center of the base portion than the outer fin on one surface side of the base portion. A portion of the outer peripheral side of the outer fin projecting outward from the outer edge of the base portion, and a portion of the inner peripheral side of the outer fin and a portion of the outer peripheral side of the inner fin. And the height of the inner fin from the base portion is higher than the height of the outer fin from the base portion, and the outer fin extends outside the outer edge of the base portion and the inner side through the gap. An air-cooling heat sink having a portion between the fin and the overlapping range.

  According to the present invention, the air flowing from the air inlet efficiently hits the heat radiating fins that protrude outward from the base portion of the heat sink, and the wind in the air passage formed along the inner wall of the exterior effectively radiates heat. Since it hits the surface of the fin, efficient heat dissipation becomes possible.

It is a perspective view of the lighting fixture of Embodiment 1 of this invention. It is the top view which looked at the lighting fixture shown in FIG. 1 from the opposite side to the light source part. It is the bottom view which looked at the lighting fixture shown in FIG. 1 from the light source part side. It is a side view of the lighting fixture shown in FIG. It is the side view which removed the exterior of the lighting fixture shown in FIG. It is the side view which removed the exterior of the lighting fixture shown in FIG. It is a perspective view which shows the other structural example of the light source part and heat sink of the lighting fixture of Embodiment 1 of this invention. It is a perspective view which shows the other structural example of the light source part and heat sink of the lighting fixture of Embodiment 1 of this invention. It is a perspective view of the state which isolate | separated the light source part and heat sink which are shown in FIG. It is a perspective view which shows the other structural example of the lighting fixture of Embodiment 1 of this invention. It is a perspective view of the lighting fixture of Embodiment 2 of this invention. It is the perspective view which removed the exterior of the lighting fixture of Embodiment 3 of this invention. It is the bottom view which looked at the light source part and heat sink of the lighting fixture of Embodiment 3 of this invention from the light source part side. It is the top view which looked at the light source part and heat sink of the lighting fixture of Embodiment 3 of this invention from the opposite side to the light source part. It is a perspective view of the light source part and heat sink with which the lighting fixture of Embodiment 4 of this invention is provided. It is a perspective view of the light source part and heat sink with which the lighting fixture of Embodiment 5 of this invention is provided. It is a perspective view of the light source part and heat sink with which the lighting fixture of Embodiment 6 of this invention is provided. It is the perspective view which looked at the lighting fixture of Embodiment 7 of this invention from the light source part side. It is the perspective view which looked at the state which removed the exterior from the lighting fixture of Embodiment 7 of this invention from the light source part opposite side. It is the perspective view which looked at the state which removed the exterior from the lighting fixture of Embodiment 7 of this invention from the light source part side. It is a side view of the state which removed the exterior from the lighting fixture of Embodiment 7 of this invention. It is the top view which looked at the state which removed the exterior from the lighting fixture of Embodiment 7 of this invention from the opposite side to the light source part. It is the bottom view which looked at the state which removed the exterior from the lighting fixture of Embodiment 7 of this invention from the light source part.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted. In addition, the present invention includes all combinations of the embodiments described below.

Embodiment 1 FIG.
FIG. 1 is a perspective view of a lighting fixture according to Embodiment 1 of the present invention. As illustrated in FIG. 1, the luminaire 1 </ b> A according to the first embodiment includes a light source unit 2, a heat sink 3, an exterior 4, a support member 5, and a column 6. This luminaire 1A is used as a ceiling light, and is particularly suitable as a high ceiling ceiling light used by being suspended from a ceiling.

  2 is a plan view of the luminaire 1A shown in FIG. 1 as viewed from the side opposite to the light source unit 2, that is, from the upper side. 3 is a bottom view of the luminaire 1A shown in FIG. 1 as viewed from the light source unit 2 side, that is, the lower side. FIG. 4 is a side view of the lighting fixture 1A shown in FIG. FIG. 5 is a side view of the lighting fixture 1A shown in FIG. FIG. 5 is a side view of the lighting fixture 1A shown in FIG. FIG. 6 is a side view of the lighting fixture 1A shown in FIG. 1 with the exterior 4 removed. 5 and 6 are views seen from different directions by 90 °.

  The light source unit 2 included in the lighting fixture 1A of the first embodiment shown in these drawings includes a substrate 2a and a plurality of LED light sources 2b mounted on the substrate 2a. The number of LED light sources 2b mounted on the substrate 2a is set based on the size of the luminous flux required for the lighting fixture 1A. The substrate 2a has a rectangular shape. The plurality of LED light sources 2b are arranged in a matrix. The substrate 2a is preferably a metal substrate or a ceramic substrate. Although it does not specifically limit as the LED light source 2b, For example, a surface mount type small LED package etc. can be used. Moreover, the structure of the light source part in this invention is not limited to the structure of illustration. For example, a chip-on-board (COB) type LED light source may be used as the light source unit. The light source unit in the present invention may use a light source other than the LED light source, for example, an organic EL (Electro-Luminescence) light source.

  As shown in FIGS. 1 and 3, in the first embodiment, the light source unit 2 has a central region 2c where the LED light source 2b is not arranged. The central region 2c has a smaller light source heat generation amount per area than the surrounding region. Generally, the larger the heat sink 3 is, the more easily heat is accumulated in the central portion of the heat sink 3. On the other hand, in the first embodiment, the amount of heat transmitted to the central portion of the heat sink 3 can be reduced by providing the central region 2c having a light source heat generation amount per area smaller than that of the surrounding region. It is possible to suppress heat from being accumulated in the central portion. In the configuration shown in the figure, the number of LED light sources 2b in the central region 2c is zero. However, the number of LED light sources 2b per area in the central region 2c is smaller than that in the surrounding region. The same effect can be obtained.

  The heat sink 3 has a base part 3a located on the back side of the light source part 2, that is, the opposite side to the LED light source 2b, and a plurality of heat radiation fins 3b protruding from the surface of the base part 3a opposite to the light source part 2. The base portion 3 a has a rectangular plate shape having a size including the range of the light source portion 2. The light source unit 2 is fixed to the base unit 3a by, for example, screwing. You may insert the heat conductive sheet etc. which have high heat conductivity between the light source part 2 and the base part 3a. When the substrate 2a of the light source unit 2 is made of metal, it is desirable to provide an insulating member between the light source unit 2 and the base unit 3a. The heat conductive sheet may be an insulating member.

  The radiating fin 3b protrudes perpendicularly to the base portion 3a. The heat radiating fins 3b are rectangular. The plurality of radiating fins 3b are arranged in parallel to each other. As shown in FIG. 3, when the heat sink 3 is viewed from the light source unit 2 side, the radiation fins 3b project outward from the outer edge of the base unit 3a. Both end portions of the radiating fin 3b project outward from the outer edge of the base portion 3a. When the heat sink 3 is viewed from the light source unit 2 side, the length of the heat radiation fin 3b is longer than the length of the base portion 3a along the heat radiation fin 3b.

  The heat sink 3 is preferably made of a metal having high thermal conductivity, such as aluminum or an alloy thereof. The base portion 3a and the heat radiating fins 3b are composed of different parts. The base part 3a and the radiation fin 3b are joined by a method such as caulking or welding. The heat transferred from the light source part 2 to the base part 3a is further transferred to the radiation fin 3b. And it is radiated from the surface of the radiation fin 3b. According to the heat sink 3, the heat radiation area can be increased in this way. Heat dissipation is promoted by natural convection of air on the surface of the heat dissipation fin 3b. Since the heat sink 3 has a simple shape, the heat sink 3 can be formed by assembling the base portion 3a and the heat radiating fins 3b formed of different parts. Therefore, the base part 3a and the heat radiating fins 3b can be constituted by parts obtained by processing a metal material having a high thermal conductivity. For this reason, compared with the heat sink of the complicated shape which needs to manufacture with the aluminum die-casting etc. with low heat conductivity, the outstanding heat dissipation is acquired. You may comprise the base part 3a and the thermal radiation fin 3b with another material. For example, the material of the radiating fin 3b may be aluminum, and the material of the base portion 3a may be copper having a higher thermal conductivity than aluminum. By making the thermal conductivity of the base part 3a higher than the thermal conductivity of the radiation fins 3b, more excellent heat dissipation can be obtained.

  The exterior 4 covers the outer periphery of the heat sink 3. As shown in FIGS. 1 and 2, the exterior 4 has an exhaust port 4 a that exhausts air at a portion opposite to the light source unit 2, that is, at the top. There is an interval between the end of the heat dissipating fin 3b projecting outward from the outer edge of the base portion 3a and the exterior 4. That is, the exterior 4 and the heat sink 3 are not in contact. The exterior 4 has a lower part 4b that covers the entire outer periphery of the heat sink 3 with a space between it and the upper part 4c provided on the upper side. The cross-sectional shape obtained by cutting the exterior 4 along a plane parallel to the base portion 3a is a square or a rectangle. The cross-sectional area obtained by cutting the space inside the lower portion 4b along a plane parallel to the base portion 3a is constant. The cross-sectional area obtained by cutting the space inside the upper portion 4c with a plane parallel to the base portion 3a decreases upward. The shape of the upper portion 4c is the same shape as the quadrangular frustum. The exhaust port 4a opens on the upper surface of the upper portion 4c. The exhaust port 4a has a circular shape. An opening serving as an air inlet 7 through which air flows is formed in the lower portion of the lower portion 4b of the exterior 4. The air inlet 7 has an annular shape formed on the outer peripheral side of the heat sink 3 over the entire circumference. By providing an interval between the end portion of the radiating fin 3 b and the exterior 4, the opening area of the air inlet 7 can be increased. As shown in FIG. 4, the height of the lower end of the exterior 4 and the height of the lower end of the heat sink 3 (the lower surface of the base portion 3a) are substantially equal.

  The air inlet 7 is located below the heat radiating fins 3b of the portion protruding outward from the outer edge of the base portion 3a. In other words, the portion of the heat radiating fin 3 b that protrudes outward from the outer edge of the base portion 3 a is positioned above the air inlet 7. For this reason, when air convection occurs due to the heat of the light source unit 2 serving as a heat source, the air flows into the exterior 4 from the air inlet 7 and flows along the radiation fins 3b. This air passes through the inside of the exterior 4 and is discharged to the outside from the exhaust port 4a. Due to the difference between the pressure in the vicinity of the exhaust port 4 a and the pressure in the vicinity of the intake port 7, the air is sucked from the intake port 7 at the lower part of the exterior 4. When air flows along the inner wall of the exterior 4, heat can be efficiently radiated from the radiation fins 3 b. Thus, according to the lighting fixture 1A, the air flowing from the air inlet 7 efficiently hits the heat dissipating fins 3b projecting outward from the base portion 3a, and the air path formed along the inner wall of the exterior 4 Since the wind effectively hits the surface of the heat radiation fin 3b, efficient heat radiation can be achieved by natural convection. As a result, since the temperature of the LED light source 2b is lowered, the light emission efficiency of the LED light source 2b can be improved and the lifetime can be extended. In particular, in the first embodiment, when viewed from the light source unit 2 side, both end portions of the heat radiating fins 3b protrude outward from the outer edge of the base portion 3a, so that the heat radiation efficiency can be further improved.

  Further, by providing the exterior 4, it is possible to suppress the accumulation of dust on the heat sink 3 or the like. Moreover, the designability can be improved by making the heat sink 3 invisible by the exterior 4. In addition, the shape of the radiation fin in this invention is not limited to a rectangle. For example, the shape of the radiating fins may be a shape that is obliquely cut out along the inclined inner wall of the upper portion 4 c of the exterior 4. By adopting such a shape, wind along the inclined inner wall of the exterior 4 can be efficiently applied to the radiating fins.

  As shown in FIG. 3, when the length of the radiating fin 3b in the direction parallel to the base portion 3a is L1, and the length of the base portion 3a along the radiating fin 3b is L2, L1 is 1. It is preferable that it is 43 times or less. This is because even if L1 is made longer than 1.43 times L2, the effect of further reducing the temperature of the LED light source 2b is reduced. Further, from the viewpoint of sufficiently improving heat dissipation and sufficiently reducing the temperature of the LED light source 2b, L1 is preferably 1.1 times or more of L2, and L1 is 1.3 times or more of L2. Is more preferable.

  As shown in FIG. 1, the support member 5 supports the heat sink 3 inside the exterior 4. The support member 5 has two arm portions 5a and a base portion 5b. The tip, that is, the lower end of the arm portion 5 a is fixed to the base portion 3 a of the heat sink 3. The arm part 5a supports the heat sink 3 from the side facing the surface of the radiation fin 3b. That is, the arm portion 5 a does not face the end portion of the heat radiating fin 3 b that projects outward from the outer edge of the base portion 3 a of the heat sink 3. For this reason, the support member 5 does not obstruct air convection between the radiation fins 3b. The base part 5b is located between the base end parts, that is, the upper end parts of the two arm parts 5a. A part of the base 5b and a part of the exhaust port 4a of the exterior 4 are overlapped. A hole 5c through which air can pass is formed in a base portion 5b that overlaps the exhaust port 4a. That is, the hole 5c overlaps the exhaust port 4a.

  The lower end portion of the support column 6 is fixed to the upper surface of the base portion 5 b of the support member 5. The upper end portion of the column 6 is attached to the ceiling. The lighting fixture 1 </ b> A is suspended from the ceiling by the column 6. The upper surface of the upper portion 4 c of the exterior 4 is fixed to the base portion 5 b of the support member 5. The column 6 has a truncated cone-shaped portion whose outer diameter decreases downward.

  Since air convection occurs due to a pressure difference between the intake port 7 and the exhaust port 4a, the opening area of the intake port 7 and the opening area of the exhaust port 4a are preferably substantially the same area. Here, the opening area of the intake port 7 refers to the effective opening area of the intake port 7, and the opening area of the exhaust port 4a refers to the effective opening area of the exhaust port 4a. In the first embodiment, the area obtained by subtracting the projected area of the heat sink 3 and the support member 5 from the opening area of the outer package 4 when viewed from the light source unit 2 side (FIG. 3), that is, the opening area of the lower portion 4b. This corresponds to the effective opening area of the mouth 7. The effective opening area of the exhaust port 4a corresponds to the sum of the area of the exhaust port 4a that does not overlap the base 5b of the support member 5 and the total area of the holes 5c in the base 5b.

  7 and 8 are perspective views showing another configuration example of the light source unit and the heat sink of the lighting fixture according to Embodiment 1 of the present invention. FIG. 9 is a perspective view showing a state where the light source unit and the heat sink shown in FIG. 8 are separated. In the configuration example shown in FIGS. 7 to 9, the length from the end on the base portion 3 a side of the radiating fin 3 b to the end on the opposite side is longer than that in the configuration of FIGS. 1 to 6. . 8 and FIG. 9, the number of LED light sources 2b arranged per area in the central region of the light source unit 2 is the same as the number of LED light sources 2b arranged per area in the region around the central region. It has become.

  FIG. 10 is a perspective view showing another configuration example of the lighting fixture according to Embodiment 1 of the present invention. The lighting fixture 1B shown in FIG. 10 is the same as the lighting fixture 1A of FIGS. 1 to 6 except that the shape of the exterior 4 is different. The cross-sectional shape obtained by cutting the exterior 4 of the lighting fixture 1B shown in FIG. 10 along a plane parallel to the base portion 3a is a circle. The cross-sectional area obtained by cutting the space inside the exterior 4 of the lighting fixture 1B shown in FIG. 10 by a plane parallel to the base portion 3a decreases upward. In the lighting fixture 1B shown in FIG. 10, the same effects as those of the lighting fixture 1A shown in FIGS. Although not shown, in the present invention, the shapes of the base portion 3a and the light source portion 2 of the heat sink 3 are not limited to rectangles, and the same effect can be obtained with other shapes such as a circle.

Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described with reference to FIG. 11. The description will focus on the differences from the first embodiment described above, and the same or corresponding parts will be denoted by the same reference numerals. Is omitted. FIG. 11 is a perspective view of a lighting fixture according to Embodiment 2 of the present invention.

  A lighting fixture 1C according to the second embodiment shown in FIG. 11 is characterized in that the light source unit 2 and the heat sink 3 are supported by a light source mounting base 8 instead of the support member 5 according to the first embodiment. The light source mounting base 8 is attached to the lower part of the exterior 4 of the lighting fixture 1C. The light source unit 2 included in the lighting fixture 1C has one light emitting region 2d having a large area provided on the substrate 2a. The light emitting area 2d has a rectangular shape. The light source unit 2 is attached to the lower surface of the light source mounting base 8 via a heat conductive sheet. The heat sink 3 is attached to the upper surface of the light source mounting base 8. That is, the light source mounting base 8 is sandwiched between the base portion 3 a of the heat sink 3 and the light source portion 2. A plurality of air inlets 8 a are formed in the light source mounting base 8. The air inlet 8 a is located below the heat radiating fin 3 b of the portion that protrudes outward from the outer edge of the base portion 3 a of the heat sink 3. An exhaust port 4 a similar to that in the first embodiment is formed in the upper portion of the exterior 4. The cross-sectional shape of the support | pillar 6 with which lighting fixture 1C is provided makes a rectangular shape. The upper end of the exterior 4 is fixed to the lower end of the column 6. In the lighting fixture 1C of the second embodiment, air flows into the exterior 4 from the intake port 8a, and the air is discharged from the exhaust port 4a. According to the lighting fixture 1C of the second embodiment, the same effects as those of the first embodiment can be obtained. Further, when a material such as alumina having high insulation and high emissivity is used as the material of the light source mounting base 8, it is not necessary to put a heat conductive sheet between the light source unit 2 and the light source mounting base 8.

Embodiment 3 FIG.
Next, the third embodiment of the present invention will be described with reference to FIG. 12 to FIG. 14. The description will focus on the differences from the first embodiment described above, and the same or corresponding parts will be denoted by the same reference numerals. The description is omitted. FIG. 12 is a perspective view in which the exterior 4 of the lighting fixture according to Embodiment 3 of the present invention is removed. FIG. 13 is a bottom view of the light source unit 2 and the heat sink 3 of the lighting fixture according to the third embodiment of the present invention as viewed from the light source unit 2 side, that is, the lower side. FIG. 14 is a plan view of the light source unit 2 and the heat sink 3 of the lighting apparatus according to Embodiment 3 of the present invention as viewed from the side opposite to the light source unit 2, that is, from the upper side.

  As shown in these drawings, in the third embodiment, an opening 9 through which air can pass is formed in the base portion 3 a of the heat sink 3 and the central portion of the light source portion 2. In the third embodiment, the air heated on the light source unit 2 side flows through the openings 9 and between the radiation fins 3b. For this reason, the air flow in the central portion of the radiating fin 3b is improved, and the heat radiating efficiency of the central portion of the heat sink 3 where heat is likely to be trapped is improved, so that even better heat dissipation is obtained compared to the first embodiment. Since the third embodiment is the same as the first embodiment except for the matters described above, further description is omitted.

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described with reference to FIG. 15. The description will focus on the differences from the first embodiment described above, and the same or corresponding parts will be denoted by the same reference numerals. Is omitted. FIG. 15 is a perspective view of light source unit 2 and heat sink 3 provided in the lighting fixture according to Embodiment 4 of the present invention.

  As shown in FIG. 15, all the heat radiating fins 3c included in the heat sink 3 of Embodiment 4 have a U-shape having a recess 3d on the side opposite to the base portion 3a. That is, the shape of the radiation fin 3c is a shape in which a small rectangle (recess 3d) is cut out from one side of the rectangle. In a lighting fixture with a large amount of heat generation, since the heat sink 3 is large, an airflow due to natural convection hardly passes through the central portion of the heat sink 3. For this reason, in the center part of the heat sink 3, the heat dissipation effect of the radiation fin 3c becomes low. In the fourth embodiment, the radiating fin 3c has a U-shape, and the portion corresponding to the rectangular recess 3d is eliminated from the central portion of the radiating fin 3c, which has a low radiating effect, so that the radiating effect is hardly reduced. The weight of the fin 3c can be made sufficiently light. For this reason, the heat sink 3 can be sufficiently reduced in weight as the entire heat sink 3 without substantially reducing the heat dissipation effect.

  The length L3 in the direction perpendicular to the base portion 3a of the recess 3d of the radiating fin 3c is preferably ½ or less of the length L4 in the direction perpendicular to the base portion 3a of the radiating fin 3c. The length L5 in the direction parallel to the base portion 3a of the recess 3d of the radiating fin 3c is preferably less than or equal to ½ of the length L6 in the direction parallel to the base portion 3a of the radiating fin 3c. When the size of the recess 3d is in the above range, the heat dissipation effect of the heat sink 3 can be more reliably suppressed. Further, the inner edge of the recess 3d of the radiating fin 3c is parallel to the outer edge of the radiating fin 3c other than the recess 3d. For this reason, in the process of forming the recess 3d of the radiating fin 3c, the outer edge of the radiating fin 3c is used as a reference for positioning, so that the recess 3d can be formed at an accurate position, and manufacturing is facilitated.

  The light source unit 2 shown in FIG. 15 has one light emitting region 2e having a large area provided on the substrate 2a. The light emitting region 2e has a shape obtained by removing the small rectangular central region 2c from the large rectangle. For this reason, the central region 2c has a smaller light source heat generation amount per area than the surrounding region. By providing the central region 2c, the amount of heat transmitted to the central portion of the heat sink 3 can be reduced, so that heat can be more reliably suppressed from being stored in the central portion of the heat sink 3 where the heat dissipation effect of the radiating fins 3c is low. Since the fourth embodiment is the same as the first embodiment except for the matters described above, further description is omitted.

Embodiment 5. FIG.
Next, a fifth embodiment of the present invention will be described with reference to FIG. 16. The description will focus on the differences from the first and fourth embodiments described above, and the same or corresponding parts will be denoted by the same reference numerals. The description is omitted. FIG. 16 is a perspective view of light source unit 2 and heat sink 3 provided in the lighting fixture according to Embodiment 5 of the present invention.

  As shown in FIG. 16, the heat sink 3 of the fifth embodiment includes a U-shaped heat radiation fin 3c (first heat radiation fin) and a second heat radiation fin 3e similar to those of the fourth embodiment. The shape of the 2nd radiation fin 3e is a rectangle. The overall length from the end on the base portion 3a side of the second radiating fin 3e to the opposite end thereof is shorter than the overall length from the end on the base portion 3a side of the radiating fin 3c to the opposite end thereof. The total length from the end on the base portion 3a side of the second radiating fin 3e to the end on the opposite side is substantially the same as the length from the end on the base portion 3a side of the radiating fin 3c to the recess 3d. The radiation fins 3c and the second radiation fins 3e are alternately arranged. According to the fifth embodiment, the fin pitch of the portion far from the base portion 3a of the radiating fin 3c, that is, the portion located on both sides of the recess 3d can be widened, and the heat radiating effect is enhanced. Since the fifth embodiment is the same as the first and fourth embodiments except for the matters described above, the description thereof is omitted.

Embodiment 6 FIG.
Next, a sixth embodiment of the present invention will be described with reference to FIG. 17. The description will focus on the differences from the first embodiment described above, and the same or corresponding parts will be described with the same reference numerals. Is omitted. FIG. 17 is a perspective view of the light source unit 2 and the heat sink 3 included in the lighting fixture according to Embodiment 6 of the present invention.

  As shown in FIG. 17, the heat sink 3 of the sixth embodiment includes first radiating fins 3f and second radiating fins 3g. The shape of the 1st radiation fin 3f and the 2nd radiation fin 3g is a rectangle. The total length from the end on the base portion 3a side of the second radiating fin 3g to the opposite end thereof is shorter than the total length from the end on the base portion 3a side of the first radiating fin 3f to the opposite end thereof. . The first heat radiating fins 3f and the second heat radiating fins 3g are alternately arranged. According to the sixth embodiment, it is possible to increase a fin pitch in a portion far from the base portion 3a of the first radiating fin 3f, that is, a portion longer than the second radiating fin 3g, and the heat radiating effect is enhanced. Since the sixth embodiment is the same as the first embodiment except for the matters described above, the description thereof will be omitted.

Embodiment 7 FIG.
Next, the seventh embodiment of the present invention will be described with reference to FIGS. 18 to 23. The difference from the above-described first embodiment will be mainly described, and the same portions or corresponding portions will be denoted by the same reference numerals. The description is omitted. FIG. 18 is a perspective view of the lighting fixture 1D according to the seventh embodiment of the present invention as viewed from the light source unit 2 side. 19 to 23 are views showing a state in which the exterior 4 is removed from the lighting fixture 1D according to the seventh embodiment of the present invention. FIG. 19 is a perspective view seen from the side opposite to the light source unit 2, and FIG. 21 is a side view, FIG. 21 is a side view, FIG. 22 is a plan view viewed from the side opposite to the light source unit 2, and FIG. 23 is a bottom view viewed from the light source unit 2.

  As illustrated in FIG. 18, the lighting fixture 1 </ b> D of the seventh embodiment includes a light source unit 2, a heat sink 10, and an exterior 4 that covers the outer periphery of the heat sink 10. The heat sink 10 includes a disk-shaped base portion 11 and a plurality of outer fins 12 (radiation fins) arranged radially on one surface side of the base portion 11. That is, by arranging the plurality of outer fins 12 at intervals along the circumferential direction of the base portion 11, these outer fins 12 exhibit a radial shape. A portion of the outer peripheral side of the outer fins 12 arranged in a radial manner protrudes outward from the outer edge of the base portion 11. The light source unit 2 is disposed on the other surface side of the base unit 11. The light source unit 2 is fixed to the heat sink 10 by an annular light source fixing frame 15. The light source fixing frame 15 is fixed to the other surface side of the base portion 11 concentrically with the base portion 11. The light source unit 2 is fixed by sandwiching the four corners of the substrate 2 a of the light source unit 2 between the base unit 11 and the light source fixing frame 15.

  The exterior 4 is generally cylindrical and is concentrically disposed on the outer peripheral side of the heat sink 10. Between the lower end part of the exterior 4 and the heat sink 10, an opening serving as an air inlet 7 through which air flows is formed. In FIG. 18, illustration of the upper part of the exterior 4 is omitted, but an exhaust port for exhausting air is provided in the upper part of the exterior 4.

  As shown in FIG. 23, the substrate 2a of the light source unit 2 has a square shape. The plurality of LED light sources 2b mounted on the substrate 2a are arranged in a generally circular area. Moreover, the light source part 2 has the center area | region 2c where the LED light source 2b is not arrange | positioned.

  As shown in FIGS. 19 to 21, the heat sink 10 further includes a plurality of inner fins 13 arranged radially. The plurality of inner fins 13 are arranged at intervals along the circumferential direction of a virtual circle smaller than the outer edge of the base portion 11, so that these inner fins 13 exhibit a radial shape. The inner fin 13 protrudes vertically from one surface side of the base portion 11. The inner fin 13 is located closer to the center of the base portion 11 than the outer fin 12. The height of the inner fin 13 from the base portion 11 is higher than the height of the outer fin 12 from the base portion 11. That is, the length of the inner fin 13 in the direction perpendicular to the base portion 11 is longer than the length of the outer fin 12 in the direction perpendicular to the base portion 11.

  As shown in FIG. 22, when viewed from one surface side of the base portion 11, the length of the portion 12 a on the outer peripheral side of the outer fin 12 protruding outward from the outer edge of the base portion 11 is shorter than the length of the other portions. . In addition, a portion 12b on the inner peripheral side of the radially outer fins 12 and a portion 13a on the outer peripheral side of the radially inner fins 13 overlap with each other through a gap. In other words, the end on the inner peripheral side of the outer fin 12 is located on the inner peripheral side compared to the end on the outer peripheral side of the inner fin 13. The total number of inner fins 13 is equal to the total number of outer fins 12. The inner fins 13 are alternately arranged with the outer fins 12 along the circumferential direction.

  The inner fin 13 is disposed in a region on the opposite side (back side) of the heat generation region of the light source unit 2 (that is, the region where the LED light source 2 b is disposed) via the base unit 11. The inner fin 13 is not disposed in the central portion of the base portion 11. That is, the inner peripheral end of the inner fin 13 does not reach the center of the base 11. The central portion where the inner fins 13 are not disposed corresponds to a region on the back surface side of the central region 2c of the light source unit 2 where the LED light source 2b is not disposed.

According to the seventh embodiment described above, in addition to the same effects as in the first embodiment, the following effects can be obtained.
(1) Since the air sucked from the air inlet 7 is guided to the inner fin 13 by the outer fin 12, the air can be efficiently applied to the inner fin 13 to radiate heat. At this time, the air sucked from the air inlet 7 flows along the outer fin 12, passes through the gap between the inner peripheral portion 12 b of the outer fin 12 and the outer peripheral portion 13 a of the inner fin 13, and passes through the inner fin. It flows to 13.
(2) Since the inner fin 13 is disposed in the region on the back side of the heat generation region of the light source unit 2, the heat generated by the light source unit 2 is mainly transferred to the inner fin 13. Since the inner fin 13 efficiently dissipates heat in (1) above, the temperature of the light source unit 2 is lowered, so that the light emission efficiency of the light source unit 2 can be improved and the life can be extended.
(3) Since the height of the inner fin 13 from the base portion 11 is higher than the height of the outer fin 12 from the base portion 11, eddy currents are generated along the outer fin 12 and the inner fin 13, and thus more efficiently. Air can be applied to the inner fins 13. Moreover, since the surface area of the inner fin 13 becomes large, the light source part 2 can be made into low temperature.
(4) Since the outer fins 12 and the inner fins 13 are alternately arranged along the circumferential direction, the effect (1) can be more reliably exhibited.

  The outer fin 12 and the inner fin 13 may be made of the same material, but the outer fin 12 and the inner fin 13 may be made of different materials. In particular, it is preferable that the thermal conductivity of the constituent material of the inner fin 13 is higher than the thermal conductivity of the constituent material of the outer fin 12. For example, the inner fin 13 may be made of a metal material, and the outer fin 12 may be made of a heat radiation resin. Since the main role of the outer fin 12 is to guide air to the inner fin 13, even if the thermal conductivity is somewhat lower than that of the inner fin 13, the heat dissipation performance of the heat sink 10 does not deteriorate so much. For this reason, the heat sink 10 can be reduced in weight by suppressing the fall of the heat dissipation performance of the heat sink 10 by comprising the outer fin 12 with lightweight materials, such as a thermal radiation resin.

1A, 1B, 1C, 1D Lighting fixture, 2 light source part, 2a substrate, 2b LED light source, 2c central area, 2d, 2e light emitting area, 3 heat sink, 3a base part, 3b, 3c heat radiation fin, 3d recess, 3e, 3g 2nd radiation fin, 3f 1st radiation fin, 4 exterior, 4a exhaust port, 4b lower part, 4c upper part, 5 support member, 5a arm part, 5b base part, 5c hole, 6 strut, 7 air inlet, 8 light source Mounting base, 8a Intake port, 9 opening, 10 Heat sink, 11 Base part, 12 Outer fin, 12a, 12b part, 13 Inner fin, 13a part, 15 Light source fixing frame

Claims (21)

A heat sink having a plate-like base portion and a plurality of heat dissipating fins protruding from one side of the base portion;
A light source unit disposed on the other surface side of the base unit;
Covering the outer periphery of the heat sink, and an exterior having an exhaust port at the top;
A support member that supports the heat sink inside the exterior;
With
When the heat sink is viewed from the light source part side, the heat radiating fins protrude outward from the outer edge of the base part,
Air flows into the exterior from the intake port located below the heat radiating fin, and the air is discharged from the exhaust port ,
The plurality of radiating fins are arranged in parallel,
The said supporting member is a lighting fixture which supports the said heat sink from the side facing the surface of the said radiation fin . A heat sink having a plate-like base portion and a plurality of heat dissipating fins protruding from one side of the base portion;
A light source unit disposed on the other surface side of the base unit;
Covering the outer periphery of the heat sink, and an exterior having an exhaust port at the top;
With
When the heat sink is viewed from the light source part side, the heat radiating fins protrude outward from the outer edge of the base part,
Air flows into the exterior from the intake port located below the heat radiating fin, and the air is discharged from the exhaust port ,
The exterior has a frustum-shaped portion in which a cross-sectional area obtained by cutting an inner space along a plane parallel to the base portion decreases upward.
The said exhaust port is an illuminating device opened to the upper surface of the said frustum-shaped part, and does not open to the surrounding wall of the said frustum-shaped part . The lighting fixture of Claim 1 or Claim 2 which has a center area | region where the emitted-heat amount per area is small compared with the surrounding area | region.   4. The length of the heat radiating fin in a direction parallel to the base portion is 1.43 times or less of the length of the base portion along the heat radiating fin. 5. Lighting fixtures.   The lighting fixture according to any one of claims 1 to 4, wherein an opening area of the intake port is equal to an opening area of the exhaust port.   The lighting fixture according to any one of claims 1 to 5, wherein the lighting fixture is located at a center of the base portion and has an opening through which air can pass from the light source portion side to the radiation fin side.   7. The illumination according to claim 1, wherein at least a part of the plurality of the heat radiating fins has a U shape having a recess on a side opposite to the base portion. Instruments.   The length of the concave portion of the U-shaped radiating fin in the direction perpendicular to the base portion is ½ or less of the length of the radiating fin in the direction perpendicular to the base portion, and the concave portion The lighting fixture according to claim 7, wherein a length in a direction parallel to the base portion is ½ or less of a length in a direction parallel to the base portion of the radiating fin.   The lighting fixture according to claim 7 or 8, wherein an inner edge of the concave portion of the U-shaped radiating fin is parallel to an outer edge of the radiating fin.   The lighting fixture according to any one of claims 1 to 9, wherein when the heat sink is viewed from the light source unit side, both end portions of the heat radiating fin project outward from an outer edge of the base portion.   The lighting fixture according to any one of claims 1 to 10, wherein there is a gap between an end portion of the radiating fin projecting outward from an outer edge of the base portion and the exterior.   The plurality of radiating fins include a first radiating fin and a second radiating fin having a total length from an end on the base portion side to an end opposite to the base portion, which is shorter than the first radiating fin, The lighting fixture according to any one of claims 1 to 11, wherein the first radiating fins and the second radiating fins are alternately arranged. A heat sink having a plate-like base portion and a plurality of heat radiation fins protruding from one surface side of the base portion, and being used by arranging a light source portion on the other surface side of the base portion,
At least a part of the plurality of radiating fins has a U-shaped shape having a recess on a side opposite to the base portion,
When the heat sink is viewed from the base portion side , both end portions of the U-shaped radiating fins protrude outward from the outer edge of the base portion,
Distance from the base portion to the recess, the U-shaped the base portion perpendicular direction more than 1/2 der Ru heatsink length of the radiating fin. Is the length in a direction parallel to the base portion of the front Symbol recess, the heat sink of claim 13 wherein the base portion is 1/2 or less parallel direction length of the radiating fin.   The heat sink according to claim 13 or 14, wherein an inner edge of the concave portion of the U-shaped radiating fin is parallel to an outer edge of the radiating fin. The heat sink has the heat dissipating fins arranged radially when viewed from the one surface side of the base part and the inner fins arranged radially at positions closer to the center of the base part than the heat dissipating fins. The lighting fixture according to claim 2 , wherein a part on the inner peripheral side of the radiating fin and a part on the outer peripheral side of the inner fin overlap with each other via a gap.   The lighting fixture according to claim 16, wherein a height of the inner fin from the base portion is higher than a height of the radiation fin from the base portion.   The lighting fixture according to claim 16 or 17, wherein the inner fin is disposed in a region on the opposite side of the heat generation region of the light source unit via the base portion.   The lighting fixture according to any one of claims 16 to 18, wherein a thermal conductivity of a constituent material of the inner fin is higher than a thermal conductivity of a constituent material of the radiating fin.   The lighting fixture according to any one of claims 16 to 19, wherein the heat dissipating fins and the inner fins are alternately arranged in a circumferential direction. A plate-like base,
Outer fins arranged radially on one side of the base portion;
Inner fins arranged radially on the one surface side of the base portion at positions closer to the center of the base portion than the outer fins;
Have
A part of the outer peripheral side of the outer fin projects outward from the outer edge of the base portion,
A portion of the inner circumferential side of the outer fin, the portion of the outer peripheral side of the inner fins have if overlapped via a gap,
A height of the inner fin from the base portion is higher than a height of the outer fin from the base portion;
The heat sink for air cooling, wherein the outer fin has a portion between a range protruding outward from the outer edge of the base portion and a range overlapping the inner fin via the gap .

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