Heat sink, light source unit and lighting fixture

Abstract

To provide a heat sink and the like capable of improving the degree of arrangement freedom of a fin in a base part, while maintaining a desired heat radiation property.SOLUTION: A heat sink 100 includes: a base part 10 which has a first surface 10a and a second surface 10b which is a surface on the opposite side from the first surface 10a; and a plurality of fins 20 fixed to the second surface 10b of the base part 10. Each of the plurality of fins 20 includes a long bottom surface part 21, and a side surface part 22 standing from an end part in the shorter direction of the bottom surface part 21, and at least at one bottom surface part 21 out of the plurality of fins 20, one or more cutout parts 23 are provided. At the second surface 10b of the base part 10, a connection part is provided for connecting components, and when the base part 10 is viewed in a plan view, the cutout parts 23 are arranged so as to overlap at least one of the connection parts.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a heat sink, a light source unit including the heat sink, and a lighting fixture including the heat sink.

Background Art

[0002] Solid light-emitting elements such as LEDs (Light Emitting Diodes) are widely used as light sources for various devices in various fields such as the lighting field or the display field. For example, in the lighting field, lighting fixtures using LEDs are known.

[0003] A lighting fixture using an LED includes, for example, a light source unit that irradiates illumination light and a fixture body that holds the light source unit. In such a lighting fixture, when the lighting fixture is turned on, light is irradiated from the light source unit and the light source unit generates heat. Specifically, the LED used as the light source of the light source unit emits light, thereby generating heat. An LED has a property that its luminous efficiency decreases and its light output decreases due to its own heat generation. Therefore, when the LED generates heat, the light output of the LED decreases, and the luminous flux of the illumination light irradiated as the lighting fixture decreases.

[0004] Therefore, in a lighting fixture using an LED, a heat sink is used to dissipate the heat generated in the light source unit. For example, a heat sink to which a light source is attached has a base portion serving as a base and a plurality of fins attached to the base portion (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the heat sink disclosed in Patent Document 1, fins having a U-shaped cross-sectional shape are fixed to the base portion. Specifically, the fins are fixed to the base portion by inserting a through hole provided in the bottom surface portion of the fin into a protrusion provided in the base portion and caulking the protrusion.

[0007] However, in addition to the protrusions for fixing the fins, the base portion is provided with structures such as convex portions, concave portions, steps, or holes. For example, as a structure of the base portion, a connection portion such as a convex portion (boss) or a through hole is provided for connecting other components such as a light source module. Therefore, the fins need to be arranged avoiding this connection portion, and there is a limitation on the arrangement position of the fins in the base portion. As a result, the number of fins may decrease and the desired heat dissipation performance cannot be maintained, or the heat sink may be enlarged to obtain the desired heat dissipation performance.

[0008] The present invention has been made to solve such problems, and an object thereof is to provide a heat sink, a light source unit, and a lighting fixture capable of improving the degree of freedom in arranging fins in a base portion while maintaining desired heat dissipation performance.

Means for Solving the Problems

[0009] To achieve the above object, one aspect of a heat sink according to the present invention includes a base portion having a first surface and a second surface opposite to the first surface, and a plurality of fins fixed to the second surface of the base portion. Each of the plurality of fins has an elongated bottom surface portion and side surface portions standing upright from end portions in the short side direction of the bottom surface portion. One or more cutout portions are provided in at least one of the bottom surface portions of the plurality of fins, and a connection portion for connecting components is provided on the second surface of the base portion. When the base portion is viewed in plan, the cutout portion is arranged so as to overlap at least one of the connection portions.

[0010] In addition, one aspect of the light source unit according to the present invention includes the above heat sink and a light source module attached to the first surface of the base portion.

[0011] In addition, one aspect of the lighting fixture according to the present invention includes the above light source unit and a fixture body that holds the light source unit.

Advantages of the Invention

[0012] It is possible to improve the degree of freedom in arranging the fins in the base portion while maintaining the desired heat dissipation performance.

Brief Description of the Drawings

[0013]

Figure 1

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BEST MODE FOR CARRYING OUT THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each of the embodiments described below shows a specific example of the present invention. Therefore, numerical values, shapes, materials, components, arrangement positions of components, connection forms, etc. shown in the following embodiments are merely examples and are not intended to limit the present invention. Thus, among the components in the following embodiments, components not described in the independent claims indicating the highest concept of the present invention are described as optional components.

[0015] Note that each figure is a schematic diagram and is not necessarily drawn precisely. Also, in each figure, substantially the same components are denoted by the same reference numerals, and overlapping descriptions are omitted or simplified. Further, in this specification, the terms "upper" and "lower" do not necessarily refer to the upward direction (vertically upward) and the downward direction (vertically downward) in an absolute spatial sense.

[0016] (Embodiment) The overall configuration of the lighting fixture 1 according to the embodiment will be described with reference to FIGS. 1 to 5. FIG. 1 is an external perspective view of the lighting fixture 1 according to the embodiment. FIGS. 2 and 3 are external perspective views of the light source unit 2 according to the embodiment, and FIGS. 4 and 5 are exploded perspective views of the light source unit 2 according to the embodiment. FIGS. 2 and 4 are perspective views of the light source unit 2 when viewed from the lens cover 300 side, and FIGS. 3 and 5 are perspective views of the light source unit 2 when viewed from the fin 20 side of the heat sink 100.

[0017] The lighting fixture 1 is an outdoor lighting used as an outdoor road lamp. The lighting fixture 1 is attached to a support column (e.g., a steel pipe pole or a utility pole) installed on the side of a road such as a roadway or a sidewalk.

[0018] As shown in FIG. 1, the lighting fixture 1 includes a light source unit 2 and a housing cover 3 that houses the light source unit 2.

[0019] The light source unit 2 irradiates illumination light. The illumination light irradiated by the light source unit 2 becomes the illumination light of the lighting fixture 1. The illumination light irradiated by the light source unit 2 is, for example, white light.

[0020] The housing cover 3 is an example of a fixture body that holds the light source unit 2. In the present embodiment, two light source units 2 are housed in the housing cover 3. The two light source units 2 are housed in the housing cover 3 such that the lens cover 300 faces the ground side (lower side). The two light source units 2 are fixed inside the housing cover 3 by screws or the like. The housing cover 3 may be made of resin or metal.

[0021] The housing cover 3 houses a power supply device that supplies power for lighting the light source unit 2 to the light source unit 2. The housing cover 3 also houses a controller or the like for controlling the lighting and extinguishing of the light source unit 2.

[0022] Although not shown, the lighting fixture 1 may be provided with an optical sensor (for example, an illuminance sensor). Thereby, the amount of natural light (external light) can be detected by the optical sensor, and the lighting and extinguishing of the light source unit 2 can be automatically controlled. For example, when it gets dark at dusk, the light source unit 2 can be automatically lit, and when it gets bright at sunrise, the light source unit 2 can be automatically extinguished.

[0023] As shown in FIGS. 2 to 5, the light source unit 2 includes a heat sink 100, a light source module 200, and a lens cover 300.

[0024] The heat sink 100 is a heat radiating member for radiating the heat generated by the light source module 200. The heat sink 100 includes a base portion 10 and a plurality of fins 20. The plurality of fins 20 are heat radiating fins for promoting heat radiation. The heat generated by the light source module 200 is conducted to the base portion 10 and the fins 20, and is radiated to the atmosphere by natural air cooling.

[0025] The base portion 10 and the fins 20 are preferably made of a material with high thermal conductivity. In the present embodiment, the base portion 10 and the fins 20 are made of a metal material such as aluminum, iron, or copper. Specifically, the base portion 10 and the fins 20 are made of a plate-shaped metal plate. As an example, the base portion 10 and the fins 20 are press-molded products made of a metal plate made of aluminum (for example, A1100) by performing press working or the like into a predetermined shape.

[0026] The thickness of the metal plate forming the base portion 10 and the thickness of the metal plate forming the fins 20 may be the same or different. In the present embodiment, the thickness of the metal plate is different between the base portion 10 and the fins 20. Specifically, the thickness of the metal plate forming the base portion 10 is greater than the thickness of the metal plate forming the fins 20. As an example, the thickness of the metal plate forming the base portion 10 is 1 mm to 4 mm, and in the present embodiment, it is 2 mm. Also, as an example, the thickness of the metal plate forming the fins 20 is 0.3 mm to 2 mm, and in the present embodiment, it is 0.8 mm.

[0027] As described above, both the base portion 10 and the fins 20 are press-molded products obtained by press-working a metal plate, and the heat sink 100 is composed only of press-molded products. Thereby, the heat sink 100 can be manufactured at low cost. Note that the heat sink 100 may be an integrally molded product formed by die-casting, rather than an assembled product in which the base portion 10 and the fins 20 are joined as separate parts.

[0028] Details of the heat sink 100 will be described later.

[0029] The light source module 200 is an LED module using an LED, and as shown in FIG. 4, includes a substrate 210 and an LED 220 disposed on the substrate 210.

[0030] The substrate 210 is a mounting substrate for mounting the LED 220. In the present embodiment, the substrate 210 is formed in a substantially rectangular shape. The substrate 210 is, for example, a printed wiring board on which metal wiring is formed in a predetermined pattern. Note that a resist made of an insulating resin material may be formed on the surface of the substrate 210 so as to cover the metal wiring in order to protect the metal wiring and ensure the insulation breakdown voltage.

[0031] As the base material constituting the substrate 210, a resin substrate made of an insulating resin material, a ceramic substrate made of a sintered body of a ceramic material such as alumina, a metal base substrate obtained by applying an insulating film to the surface of a metal base material made of a metal material such as aluminum or copper, etc. are used. In the present embodiment, the substrate 210 is a metal base substrate using an aluminum plate. Thereby, the heat generated by the LED 220 can be efficiently conducted to the heat sink 100. Note that the substrate 210 is a rigid substrate, but may be a flexible substrate.

[0032] The substrate 210 is fixed to the base portion 10 by screws. For this reason, the substrate 210 is provided with through holes 211 through which the screws are inserted. A plurality of through holes 211 are provided in the substrate 210. As shown in FIGS. 4 and 5, in the present embodiment, six through holes 211 are provided in the substrate 210.

[0033] The metal wiring formed on the substrate 210 is electrically connected to the power supply device housed in the housing cover 3. The substrate 210 and the power supply device are connected by an electric wire such as a lead wire. For example, an electrode or a connector terminal provided on the substrate 210 and the power supply device are connected by an electric wire such as a lead wire. As shown in FIG. 4, the substrate 210 is provided with a wire insertion hole 212 for inserting an electric wire connecting the substrate 210 and the power supply device. The wire insertion hole 212 is provided at the longitudinal end of the substrate 210. Also, the opening shape of the wire insertion hole 212 is circular, but is not limited thereto. Note that one wire insertion hole 212 is provided in the base portion 10.

[0034] As shown in FIGS. 4 and 5, the substrate 210 has a first surface 210a which is the surface on which the LED 220 is mounted, and a second surface 210b facing away from the first surface 210a. The first surface 210a of the substrate 210 is the surface on the lens cover 300 side, and the second surface 210b of the substrate 210 is the surface on the heat sink 100 side.

[0035] On the substrate 210, the LEDs 220 are arranged. Specifically, a plurality of LEDs 220 are arranged on the first surface 210a of the substrate 210. In the present embodiment, the plurality of LEDs 220 are mounted in a plurality of straight rows along the longitudinal direction of the substrate 210 with a predetermined interval. Note that the layout of the plurality of LEDs 220 is not limited to the pattern shown in FIG. 4. The plurality of LEDs 220 emit light by a direct current supplied from a power supply device via a wire connecting the power supply device and the substrate 210.

[0036] The LED 220 is an example of a light emitting element. In the present embodiment, each of the plurality of LEDs 220 is an individually packaged surface mount (SMD: Surface Mount Device) type LED element (LED light source). Therefore, the light source module 200 is an SMD type LED module.

[0037] The SMD type LED 220 includes a resin or ceramic white container (package), an LED chip (bare chip) mounted on the bottom of the container, and a sealing member filled in the recess of the container to seal the LED chip. In the present embodiment, the LED 220 is a white LED element that emits white light. In this case, as the LED chip, a blue LED chip that emits blue light when energized is used, and as the sealing member filled in the container, a silicone resin (phosphor-containing resin) containing a yellow phosphor such as YAG or the like is used.

[0038] The lens cover 300 is an optical member that determines the light distribution of the light emitted from the light source module 200. As shown in FIGS. 2 and 4, the lens cover 300 is arranged to cover the light source module 200.

[0039] The lens cover 300 has a plurality of lenses 310 corresponding to each of the plurality of LEDs 220 in the light source module 200, and a connecting portion 320 that connects and integrates the respective lenses 310. Each lens 310 determines the light distribution of the light emitted by the corresponding LED 220.

[0040] The lens cover 300 is a resin molded product made of a resin material having translucency, such as acrylic (PMMA) or polycarbonate (PC). In the present embodiment, the lens cover 300 is integrally formed using polycarbonate. That is, the lens 310 and the connecting portion 320 are integrally formed.

[0041] The lens cover 300 is fixed to the heat sink 100. Specifically, the lens cover 300 is fixed to the base portion 10 of the heat sink 100. For example, although not shown, the lens cover 300 is provided with protrusions (such as claw pieces), and by locking these protrusions into the through holes 13 formed in the base portion 10, the lens cover 300 can be fixed to the base portion 10.

[0042] Next, the detailed configuration of the heat sink 100 will be described in more detail with reference to FIGS. 2 to 5 and further using FIGS. 6 to 10. FIG. 6 is a plan view when the light source unit 2 according to the embodiment is viewed from the fin 20 side of the heat sink 100. FIG. 7 is an enlarged perspective view showing a part of the light source unit 2. FIG. 8 is a cross-sectional view of the light source unit 2 taken along line VIII-VIII in FIG. 6. FIG. 9 is a cross-sectional view of the heat sink 100 taken along line IX-IX in FIG. 6. FIG. 10 is a cross-sectional view of the light source unit 2 taken along line X-X in FIG. 6.

[0043] As shown in FIGS. 2 to 6, the heat sink 100 includes a base portion 10 and a plurality of fins 20 fixed to the base portion 10.

[0044] The base portion 10 is a base on which the light source module 200 is mounted. As shown in FIGS. 4, 5, and 8, the base portion 10 has a first surface 10a and a second surface 10b that is the surface opposite to the first surface 10a. The main surface of the base portion 10 is substantially rectangular. Therefore, the first surface 10a and the second surface 10b of the base portion 10 are rectangular planes.

[0045] As shown in FIG. 8, a light source module 200 is attached to the first surface 10a of the base portion 10. Specifically, a substrate 210 of the light source module 200 is attached to the first surface 10a of the base portion 10. In this case, the light source module 200 is disposed on the first surface 10a of the base portion 10 such that the second surface 210b of the substrate 210 faces the first surface 10a of the base portion 10. Thus, the first surface 10a of the base portion 10 is the surface to which the light source module 200 is attached.

[0046] Note that a heat conductive member such as grease or a thermal sheet may be inserted between the second surface 210b of the substrate 210 and the first surface 10a of the base portion 10. Thereby, the heat generated by the LED 220 can be efficiently conducted to the heat sink 100. Note that the second surface 210b of the substrate 210 and the first surface 10a of the base portion 10 may be in direct contact.

[0047] The light source module 200 is fixed to the base portion 10. As shown in FIG. 8, in the present embodiment, the light source module 200 is fixed to the base portion 10 by screws 400. In this case, the screws 400 are inserted through through-holes 211 provided in the substrate 210, and the screws 400 are screwed into holes 11 provided in the base portion 10, whereby the light source module 200 can be fixed to the base portion 10.

[0048] As shown in FIG. 8, in the present embodiment, the hole portion 11 provided in the base portion 10 is a hole having a bottom. The hole portion 11 has a shape in which a part of the first surface 10a of the base portion 10 is recessed. The hole portion 11 can be formed by performing press working on the base portion 10. Specifically, by performing press working so as to project a part of the base portion 10 from the side of the first surface 10a of the base portion 10, a part of the first surface 10a is recessed and a part of the second surface 10b is projected at the same time. Thereby, the hole portion 11 in a state of not penetrating the base portion 10 can be formed. Therefore, the hole portion 11 is a convex portion (boss) in which a hole that protrudes from the second surface 10b of the base portion 10 and has a bottom is formed. The hole portion 11 is, as an example, a bottomed cylindrical shape. That is, the top surface of the convex portion constituting the hole portion 11 is circular. Thus, the hole portion 11 which is a convex portion is an example of a connecting portion for connecting the light source module 200 (component) to the base portion 10, and is provided on the second surface 10b in the base portion 10.

[0049] Also, as in the present embodiment, by forming the hole portion 11 so as to be a bag shape that does not penetrate the base portion 10, it is possible to prevent water from entering from the second surface 10b side (fin 20 side) to the first surface 10a side (light source module 200 side) of the base portion 10. Thereby, it is possible to prevent the light source module 200 from malfunctioning due to water. The heat sink 100 configured in this way is suitable for outdoor lighting in which water easily enters the inside of the housing cover 3.

[0050] As shown in FIGS. 4 to 6, a plurality of hole portions 11 are provided in the base portion 10. The hole portion 11 is provided at a position corresponding to the through hole 211 provided in the substrate 210 of the light source module 200. That is, the hole portion 11 of the base portion 10 and the through hole 211 of the substrate 210 are provided at positions overlapping in plan view.

[0051] The hole portion 11 is provided not only at the longitudinal end of the base portion 10 but also at the longitudinal center of the base portion 10. Specifically, the hole portion 11 is provided over the entire base portion 10. Thereby, when the light source module 200 is fixed to the base portion 10, the long substrate 210 of the light source module 200 can be pressed against the base portion 10 over the entire longitudinal direction, and it is possible to suppress the substrate 210 from warping and a part of the substrate 210 floating to create a gap between the substrate 210 and the base portion 10. Thereby, the heat dissipation of the light source unit 2 can be improved. Note that the number of the hole portions 11 is the same as the number of the through holes 211 provided in the substrate 210 of the light source module 200. Therefore, in the present embodiment, as shown in FIGS. 4 to 6, six hole portions 11 are provided in the base portion 10.

[0052] Also, as shown in FIGS. 4 to 6, the base portion 10 is provided with a wire insertion hole 12 for inserting a wire that connects the power supply device housed in the housing cover 3 and the substrate 210. The opening shape of the wire insertion hole 12 is circular, but is not limited thereto. The wire insertion hole 12 of the base portion 10 and the wire insertion hole 212 of the substrate 210 are provided at positions that overlap in a plan view. The wire that connects the power supply device and the substrate 210 is inserted so as to communicate with the wire insertion hole 12 of the base portion 10 and the wire insertion hole 212 of the substrate 210.

[0053] The wire insertion hole 12 provided in the base portion 10 is an example of a connection portion for connecting a wire (component) to the light source module 200 or the power supply device, and is provided on the second surface 10b of the base portion 10. Note that, as shown in FIGS. 4 to 6, one wire insertion hole 12 is provided in the base portion 10.

[0054] Furthermore, the base portion 10 is provided with a through hole 13 (mounting hole) for attaching the lens cover 300 to the base portion 10. The opening shape of the through hole 13 is, for example, circular, but is not limited thereto. As described above, the lens cover 300 can be fixed to the base portion 10 by locking the protrusion (such as a claw piece) provided on the lens cover 300 to the through hole 13 of the base portion 10.

[0055] The through-hole 13 provided in the base portion 10 is an example of a connection portion for connecting the lens cover 300 (component) to the base portion 10, and is provided on the second surface 10b of the base portion 10. As shown in FIGS. 4 to 6, ten through-holes 13 are provided at the outer peripheral end of the base portion 10.

[0056] As shown in FIGS. 3 and 8, a plurality of fins 20 are fixed to the base portion 10. The plurality of fins 20 are fixed to the second surface 10b of the base portion 10. Specifically, twelve fins 20 are fixed to the base portion 10. In the present embodiment, the plurality of fins 20 are arranged in parallel along the longitudinal direction of the base portion 10.

[0057] As shown in FIGS. 4 to 6, the base portion 10 is provided with protrusions 14 for fixing each fin 20 to the base portion 10. The protrusions 14 protrude from the second surface 10b of the base portion 10. The protrusions 14 can be formed by performing pressing on the base portion 10. Specifically, by performing pressing so as to project a part of the base portion 10 from the first surface 10a side of the base portion 10, a part of the second surface 10b protrudes and as a result, a part of the first surface 10a is recessed. Thereby, the protrusions 14 can be formed. The protrusions 14 (before caulking) formed on the base portion 10 are columnar. Specifically, the protrusions 14 are cylindrical, but are not limited thereto.

[0058] A plurality of protrusions 14 are provided on the base portion 10. As shown in FIG. 6, in the present embodiment, one fin 20 is fixed to the base portion 10 by three protrusions 14. Also, in the present embodiment, since twelve fins 20 are used, as shown in FIG. 5, the base portion 10 is provided with twelve rows of protrusions 14 that form one row of three. That is, a total of thirty-six protrusions 14 are provided on the base portion 10.

[0059] The plurality of fins 20 fixed to the base portion 10 have the same shape as each other. Specifically, all of the 12 fins 20 have the same shape as each other. Thereby, the heat sink 100 can be manufactured at low cost and with high productivity, and a heat sink 100 with excellent mass productivity can be realized. Further, by making all the fins 20 have the same shape, the mold investment for press-molding the fins 20 can be suppressed.

[0060] As shown in FIGS. 11 and 12, each of the plurality of fins 20 has an elongated bottom surface portion 21 and side surface portions 22 that stand upright from the ends of the bottom surface portion 21 in the short side direction. The bottom surface portion 21 is a flat bottom plate, and the side surface portions 22 are flat side plates. Note that FIGS. 11 and 12 are perspective views of the fin 20. FIG. 11 shows a state when the fin 20 is viewed from the tip side of the side surface portion 22, and FIG. 12 shows a state when the fin 20 is viewed from the bottom surface portion 21 side.

[0061] As shown in FIGS. 11 and 12, in the present embodiment, the side surface portions 22 are a pair and stand upright from each of both ends of the bottom surface portion 21 in the short side direction. That is, the fin 20 has a pair of side surface portions 22 that stand upright vertically from the bottom surface portion 21. Therefore, the cross-sectional shape of each fin 20 is U-shaped. One of the pair of side surface portions 22 is the first side surface portion, and the other of the pair of side surface portions 22 is the second side surface portion. Note that in each fin 20, only one of the pair of side surface portions 22 may be provided, but by providing each of the pair of side surface portions 22, the heat dissipation performance of the heat sink 100 can be improved.

[0062] As shown in FIGS. 3 and 6, the fin 20 is fixed to the base portion 10 by attaching the bottom surface portion 21 to the base portion 10. The bottom surface portion 21 is an elongated plate-like member having a certain width, and the fin 20 is arranged such that the longitudinal direction of the bottom surface portion 21 is parallel to the short side direction of the base portion 10. The length of the bottom surface portion 21 in the longitudinal direction is approximately the same as the length (width) of the base portion 10 in the short side direction, but is not limited thereto.

[0063] As shown in FIGS. 11 and 12, in each of the plurality of fins 20, a through hole 21a is provided in the bottom surface portion 21. The fin 20 is attached to the base portion 10 by using this through hole 21a. That is, the through hole 21a is a mounting hole for attaching the fin 20 to the base portion 10. As shown in FIG. 9, the through hole 21a is a hole into which the columnar protrusion 14 (before caulking) provided on the base portion 10 is inserted. Note that the protrusion 14 shown in FIG. 9 shows the shape after caulking.

[0064] When fixing the fin 20 to the base portion 10, first, the through hole 21a of the fin 20 is inserted into the columnar protrusion 14 of the base portion 10, and the fin 20 is placed on the base portion 10. At this time, the tip of the protrusion 14 of the base portion 10 protrudes from the through hole 21a. Next, the tip of the protrusion 14 protruding from the through hole 21a is caulked. As a result, as shown in FIG. 9, the tip of the protrusion 14 is crushed and spreads laterally, and a part of the protrusion 14 (the spread portion of the protrusion 14) presses against the inner surface of the bottom surface portion 21 of the fin 20. That is, the bottom surface portion 21 is pressed by a part (caulked portion) of the protrusion 14 that has been caulked and deformed. Thereby, the fin 20 can be fixed to the base portion 10. In this way, each of the plurality of fins 20 is fixed to the base portion 10 in a state where the protrusion 14 of the base portion 10 is plastically deformed. That is, the heat sink 100 is manufactured by joining the base portion 10 and the fin 20 by plastic working (caulking).

[0065] The through hole 21a (caulking hole) in the bottom surface portion 21 is formed in a dimension that allows the protrusion 14 before caulking to be inserted. Further, a plurality of through holes 21a are provided in the bottom surface portion 21. Specifically, as shown in FIG. 12, three through holes 21a are provided in the bottom surface portion 21 along the longitudinal direction of the bottom surface portion 21. Note that the shape of the through hole 21a is not particularly limited, but as an example, the planar shape of the through hole 21a is circular.

[0066] In this way, by plastically deforming the protrusions 14 of the base portion 10 to fix the fins 20 to the base portion 10, a heat dissipation path can be secured by the plastically deformed protrusions 14 (caulked portions). Thereby, the heat dissipation performance of the heat sink 100 can be improved. By filling the inside of the through hole 21a of the bottom surface portion 21 with the protrusions 14, the heat dissipation performance of the heat sink 100 can be further improved. The heat dissipation path between the fin 20 and the base portion 10 is mainly the protrusion 14 (caulked portion). If the bottom surface portion 21 of the fin 20 is in contact with the base portion 10, this contact portion also becomes a heat dissipation path. However, due to warping of the bottom surface portion 21 or the like, a gap may enter between the bottom surface portion 21 and the second surface 10b of the base portion 10. Therefore, the contribution of the bottom surface portion 21 to heat dissipation is smaller than that of the protrusion 14 (caulked portion).

[0067] Note that the plurality of protrusions 14 are preferably provided so as to be symmetric about the center in the longitudinal direction of the base portion 10 or rotationally symmetric. Thereby, the protrusions 14 on the left half or the right half can be caulked with a mold to fix the fin 20, and the base portion 10 can be reversed left and right or rotated 180° to caulk the remaining half of the protrusions 14 with the same mold to fix the fin 20. For example, in the present embodiment, since 3×12 (total 36) protrusions 14 are provided on the base portion 10, first, 3×6 (total 18) protrusions 14 on the left half are caulked with a mold, and then the base portion 10 is rotated 180°, and the same mold is used to caulk 3×6 (total 18) protrusions 14 on the right half. Thereby, the investment in mold costs can be suppressed.

[0068] As shown in FIGS. 11 and 12, each of the pair of side surface portions 22 is a flat plate having a substantially rectangular shape as a whole. The pair of side surface portions 22 are provided so as to face each other with a distance therebetween. Specifically, the pair of side surface portions 22 are provided such that the main surfaces facing each other are parallel. Note that the pair of side surface portions 22 have the same shape and the same size, but are not limited thereto. The bottom surface portion 21 is located between the pair of side surface portions 22 and is connected to the bottom sides of the pair of side surface portions 22.

[0069] The bottom surface portion 21 and the pair of side surface portions 22 are formed by bending a metal plate. In the present embodiment, the bottom surface portion 21 and the pair of side surface portions 22 are formed so that their cross-sectional shape is substantially U-shaped. Specifically, the angle formed between the main surface of the bottom surface portion 21 and the main surfaces of the pair of side surface portions is approximately 90 degrees. That is, the bottom surface portion 21 and each side surface portion 22 are formed so that their cross-sectional shape is substantially L-shaped. Note that the connecting portion between the bottom surface portion 21 and the side surface portion 22 may be curved. Also, the bottom surface portion 21 and the pair of side surface portions 22 are not formed by only one metal plate, but the fin 20 may be formed by configuring the bottom surface portion 21 and the pair of side surface portions with separate metal plates and joining these metal plates by caulking or welding.

[0070] As shown in FIGS. 11 and 12, the bottom surface portion 21 is provided with a notch portion 23. The notch portion 23 is an opening formed so as to notch the bottom surface portion 21. The notch portion 23 may be formed without performing a notching process, or may be formed by actually performing a notching process. Specifically, the notch portion 23 may be formed by providing an opening in advance in the metal plate constituting the fin 20 and bending the metal plate into a U-shape to produce the bottom surface portion 21 and the side surface portions 22, or may be formed by notching after bending the metal plate into a U-shape to produce the bottom surface portion 21 and the side surface portions 22.

[0071] As shown in FIG. 6, the notch portion 23 is arranged so as to overlap the hole portion 11 when the base portion 10 is viewed in plan. In the present embodiment, a maximum of two hole portions 11 are arranged side by side in the short side direction of the base portion 10. For this reason, two notch portions 23 are provided in the bottom surface portion 21 of each fin 20 corresponding to these two hole portions 11. Note that in the present embodiment, since the shapes of all the fins 20 are the same, two notch portions 23 are also provided in the bottom surface portion 21 of the fin 20 arranged at a position where the hole portion 11 does not exist.

[0072] As described above, in the heat sink 100 according to the present embodiment, as shown in FIGS. 6 and 7, the notch portion 23 of the fin 20 is provided so as to overlap the hole portion 11 of the base portion 10. With this configuration, interference between the fin 20 and the hole portion 11 can be avoided, so that the fin 20 can be freely arranged at any position of the base portion 10 regardless of the position of the hole portion 11. That is, the fin 20 can be arranged on the base portion 10 without being conscious of avoiding the hole portion 11, and the degree of freedom in arranging the fin 20 can be improved. As a result, as many fins 20 as possible can be arranged on the base portion 10. Thereby, even if the heat sink 100 is manufactured as a press-molded product, the heat dissipation performance of the heat sink 100 can be maintained or improved with respect to the heat sink made of aluminum die-casting.

[0073] Further, as shown in FIGS. 11 and 12, in the present embodiment, each notch portion 23 is continuously provided over each of the bottom surface portion 21 and the pair of side surface portions 22. That is, one notch portion 23 extends from the bottom surface portion 21 to the side surface portion 22, and the notch portion 23 is provided not only on the bottom surface portion 21 but also on the pair of side surface portions 22. Specifically, the opening shape of the bottom surface portion 21 in the notch portion 23 and the opening shape of each of the pair of side surface portions 22 in the notch portion 23 are both rectangular and have the same width. Therefore, when the U-shaped fin 20 is developed in a planar shape, the opening shape of the metal plate of the portion corresponding to the notch portion 23 is a long rectangle.

[0074] By extending the notch portion 23 up to the side surface portion 22 in this way, even if the hole portion 11 exists directly below the side surface portion 22, interference between the fin 20 and the hole portion 11 can be avoided. Thereby, the degree of freedom in arranging the fin 20 can be further improved, and the heat dissipation performance of the heat sink 100 can be further improved.

[0075] Note that since the fin 20 is formed in a U-shape by the bottom surface portion 21 and the pair of side surface portions 22, it has high rigidity. Therefore, even if the notch portion 23 is provided in the fin 20, the rigidity of the fin 20 is less likely to decrease. In particular, even if the notch portion 23 extends from the bottom surface portion 21 to the side surface portion 22, the rigidity of the fin 20 does not decrease much.

[0076] Further, in the present embodiment, the notch portion 23 is provided at a position that does not interfere with the through hole 21a. That is, the notch portion 23 and the through hole 21a are not formed continuously and are formed separately at different positions.

[0077] With this configuration, the protrusion 14 inserted and caulked into the through hole 21a does not interfere with the notch portion 23. As a result, the heat conduction of the protrusion 14 (caulking portion) serving as the heat dissipation path from the base portion 10 to the fin 20 is not hindered by the notch portion 23, so the heat dissipation performance of the heat sink 100 does not deteriorate due to the presence of the notch portion 23.

[0078] As described above, according to the heat sink 100 according to the present embodiment, it is possible to improve the degree of freedom in arranging the fins 20 in the base portion 10 while maintaining the desired heat dissipation performance.

[0079] Further, the light source unit 2 according to the present embodiment includes a heat sink 100 having excellent heat dissipation performance and a light source module 200 attached to the base portion 10 of the heat sink 100. Further, the lighting fixture 1 according to the present embodiment includes a light source unit 2 having a heat sink 100 with excellent heat dissipation performance and a housing cover 3 which is an appliance body that holds the light source unit 2.

[0080] As described above, since the light source unit 2 and the lighting fixture 1 include the heat sink 100 having high heat dissipation performance, it is possible to realize a highly efficient light source unit 2 and lighting fixture 1. Further, since the notch portion 23 is provided in the fin 20, the degree of freedom in the mounting position of the light source module 200 can be improved.

[0081] In addition, in the present embodiment, the notch 23 is provided not only at a position to avoid interference with the hole 11 provided in the base portion 10, but also at a position to avoid interference with the wire insertion hole 12 and the through hole 13 provided in the base portion 10. Note that the notch 23 may be provided so as to overlap at least one of the hole 11, the wire insertion hole 12, and the through hole 13. In this way, the notch 23 may be provided so as to overlap with a connection portion for connecting some components.

[0082] Here, the heat dissipation performance of the heat sink 100 according to the embodiment will be described. Specifically, it will be described by comparing the light source unit 2 (Example 1) according to the embodiment with the light source unit 2X (Comparative Example 1) of Comparative Example 1. FIG. 13 is a perspective view of the fin 20X used in the heat sink 100X of the light source unit 2X of Comparative Example 1. FIG. 14 is a plan view of the light source unit 2X of Comparative Example 1 when viewed from the fin 20X side.

[0083] As shown in FIG. 13, the fin 20X used in the light source unit 2X of Comparative Example 1 has a shape in which the notch 23 is not provided, as compared with the fin 20 used in the light source unit 2 in the above embodiment. For this reason, in the light source unit 2X of Comparative Example 1, it is necessary to arrange the fin 20X on the base portion 10 so as not to interfere with the hole 11. As a result, as shown in FIG. 14, in the light source unit 2X of Comparative Example 1, only 8 fins 20X can be arranged on the base portion 10.

[0084] On the other hand, in the light source unit 2 (Example 1) according to the present embodiment, since the notch 23 is provided in the fin 20, the fin 20 can be arranged on the base portion 10 regardless of the position of the hole 11. As a result, in the light source unit 2 of Example 1, 12 fins 20 can be arranged on the base portion 10.

[0085] Note that in both the light source unit 2X of Comparative Example 1 and the light source unit 2 (Example 1) according to the embodiment, the fins 20X and 20 are arranged so as not to interfere with the wire insertion hole 12 and the through hole 13.

[0086] For the light source unit 2X of Comparative Example 1 configured as described above and the light source unit 2 (Example 1) according to the present embodiment, temperature analysis simulations were performed under the same conditions. The results are shown in FIG. 15. FIG. 15 is a diagram showing the simulation results of the temperature analysis of the light source unit 2 (Example 1) according to the embodiment and the light source unit 2X of Comparative Example 1.

[0087] As shown in FIG. 15, in the light source unit 2X of Comparative Example 1, the temperature at the tip of the central fin 20X was 48.5°C, whereas in the light source unit 2 of Example 1, the temperature at the tip of the central fin 20 was 46.7°C.

[0088] Also, in the light source unit 2X of Comparative Example 1, the temperature near the center of the lens cover 300 was 49.3°C, whereas in the light source unit 2 of Example 1, the temperature near the center of the lens cover 300 was 47.4°C.

[0089] Thus, it can be seen that the light source unit 2 of Example 1 has excellent heat dissipation compared to the light source unit 2X of Comparative Example 1. That is, it can be seen that by using the fin 20 provided with the notch 23, a heat sink with excellent heat dissipation can be obtained.

[0090] Next, as the light source unit 2Y of Comparative Example 2, one with 13 fins 20X without the notch 23 arranged, and as the light source unit 2 (Example 2) according to the embodiment, one with 13 fins 20 provided with the notch 23 arranged, were also subjected to temperature analysis simulations under the same temperature conditions. The results are shown in FIG. 16. FIG. 16 is a diagram showing the simulation results of the temperature analysis of the light source unit 2 (Example 2) according to the embodiment and the light source unit 2Y of Comparative Example 2.

[0091] As shown in FIG. 16, in the light source unit 2Y of Comparative Example 2, the temperature at the tip of the central fin 20X was 46.3°C, whereas in the light source unit 2 of Example 2, the temperature at the tip of the central fin 20 was 46.3°C.

[0092] Also, in the light source unit 2Y of Comparative Example 2, the temperature near the center of the lens cover 300 was 47.0°C, whereas in the light source unit 2 of Example 2, the temperature near the center of the lens cover 300 was 47.0°C.

[0093] Thus, the light source unit 2 of Example 2 and the light source unit 2Y of Comparative Example 2 have equivalent heat dissipation properties. That is, it can be seen that equivalent heat dissipation properties can be obtained whether or not the notch 23 is provided. Therefore, even if the notch 23 is provided in the fin 20, the heat dissipation property of the heat sink 100 can be maintained.

[0094] (Modification) As described above, the lighting fixture 1 according to the present invention has been described based on the embodiments, but the present invention is not limited to the above embodiments.

[0095] For example, in the above embodiment, as shown in FIG. 7, the notch 23 of the fin 20 was formed such that the edge of the notch 23 in the side surface portion 22 does not contact the hole portion 11 of the base portion 10, but it is not limited to this. Specifically, like the heat sink 100A in the light source unit 2A shown in FIGS. 17(a) and (b), the notch 23A of the fin 20A may be formed such that the edge of the notch 23A in the side surface portion 22 contacts the hole portion 11 of the base portion 10. In FIG. 17, (a) is a cross-sectional view of the light source unit 2A, and (b) is a plan view showing a part of the light source unit 2A. By forming the notch 23A in this way, the side surface portion 22 and the surface of the convex portion constituting the hole portion 11 can be brought into contact. Thereby, since the contact area between the base portion 10 and the fin 20A can be increased, the heat dissipation property of the heat sink 100A can be further improved.

[0096] In addition, in the above embodiment, the hole 11 provided in the base portion 10 of the heat sink 100 was a bottomed hole provided in the convex portion, but it is not limited to this. For example, like the light source unit 2B shown in FIG. 18, the hole 11B provided in the base portion 10B of the heat sink 100B may be a through hole penetrating the convex portion. The hole 11B can be formed by performing a flanging process on the base portion 10B. Alternatively, like the light source unit 2C shown in FIG. 19, the hole 11C provided in the base portion 10C of the heat sink 100C may not be a shape protruding from the base portion 10C, but a through hole penetrating by the thickness of the base portion 10C.

[0097] In addition, in the above embodiment, three notches 23 were provided in the bottom surface portion 21 of the fin 20, but it is not limited to this. Specifically, the number of notches 23 provided in the bottom surface portion 21 may be one, or may be three or more. That is, the number of notches 23 provided in one bottom surface portion 21 may be one or more.

[0098] In addition, in the above embodiment, the notch 23 of the fin 20 was continuously provided across the bottom surface portion 21 and the pair of side surface portions 22, but it is not limited to this. For example, the notch 23 may be continuously provided only across the bottom surface portion 21 and one of the pair of side surface portions 22. That is, the notch 23 may be continuously provided across at least one of the bottom surface portion 21 and the pair of side surface portions 22. Alternatively, the notch 23 may not be provided in either of the pair of side surface portions 22 and may be provided only in the bottom surface portion 21.

[0099] In addition, in the above embodiment, all of the 12 fins 20 had the same shape, but it is not limited to this. That is, different-shaped fins may be included among the 12 fins 20. For example, fins 20 with notches 23 provided and fins without notches 23 may be fixed to the base portion 10.

[0100] In addition, in the above-described embodiment, the notch 23 of the fin 20 was provided at a position that does not interfere with the through hole 21a in the bottom surface portion 21, but it is not limited to this. That is, the notch 23 may be provided at a position that interferes with the through hole 21a. Specifically, the notch 23 and the through hole 21a may be connected and continuously formed. In this case, the notch 23 and the through hole 21a constitute one opening.

[0101] In addition, in the above-described embodiment, the light source module 200 was an SMD type LED module using an SMD type LED element as the LED 220, but it is not limited to this. For example, the light source module may be a COB (Chip On Board) type LED module. The COB type LED module includes a substrate 210, one or more LED chips directly mounted on the substrate 210, and a sealing member (phosphor-containing resin) that seals one or more LED chips collectively or individually.

[0102] In addition, in the above-described embodiment, the light source module 200 used an LED as the light source, but it is not limited to this. For example, the light source module may use other solid light-emitting elements such as semiconductor lasers or organic EL (Electro Luminescence), or may use a lamp such as a fluorescent lamp.

[0103] In addition, in the above-described embodiment, the lighting fixture 1 is outdoor lighting, and the heat sink 100 is applicable to outdoor lighting, but it is not limited to this. For example, the present technology may be applied to indoor lighting installed indoors such as downlights or ceiling lights. Specifically, the heat sink 100 may be applied to a downlight or a ceiling light. Specifically, when applying the heat sink of the present technology to a downlight, a heat sink having a disk-shaped base portion and fins 20 radially arranged and fixed to the base portion can be used. Note that the heat sink 100 may be applied not only to devices in the lighting field but also to devices in technical fields other than the lighting field such as the display field.

[0104] In addition, the present invention also includes forms obtained by applying various modifications that can be conceived by those skilled in the art to each of the above embodiments, and forms realized by arbitrarily combining the components and functions in each of the above embodiments without departing from the gist of the present invention. Also, combinations of one or more components in each of the plurality of claims described in the claims of the present application at the time of filing are also included in the present invention. Further, when the citation form claims described in the claims of the present application at the time of filing are made into multi-claims or multi-multi-claims so as to cite any plurality of claims (for example, when made into multi-claims or multi-multi-claims so as to cite all the upper claims for each claim), all forms obtained by combinations of all the claims included in the multi-claims or multi-multi-claims are also included in the present invention.

Description of Reference Numerals

[0105] 1 Lighting fixture 2, 2A, 2B, 2C Light source unit 3 Housing cover (apparatus main body) 10, 10B, 10C Base portion 10a First surface 10b Second surface 11, 11B, 11C Hole portion (connection portion) 12 Wire insertion hole (connection portion) 13 Through hole (connection portion) 14 Protrusion 20, 20A Fin 21 Bottom surface portion 21a Through hole 22 Side surface portion 23, 23A Notch portion 100, 100A, 100B, 100C Heat sink 200 Light source module 210 Substrate

Claims

1. A base portion having a first surface and a second surface on the opposite side of the first surface, and a plurality of fins fixed to the second surface of the base portion, comprising: each of the plurality of fins has an elongated bottom portion and side portions standing upright from ends in the short side direction of the bottom portion, one or more notches are provided in at least one of the bottom portions of the plurality of fins, a connection portion for connecting components is provided on the second surface of the base portion, when the base portion is viewed in plan, the notch is arranged so as to overlap at least one of the connection portions, A heat sink.

2. The side portions are a pair and stand upright from each of both ends in the short side direction of the bottom portion, The heat sink according to Claim 1.

3. The notch is provided continuously with at least one of the bottom portion and the pair of side portions, The heat sink according to Claim 2.

4. The connection portion is a convex portion protruding from the second surface, at least one of the plurality of fins is configured such that the connection portion and the edge of the notch in the side portion are in contact with each other, The heat sink according to any one of Claims 1 to 3.

5. in each of the plurality of fins, a through hole is provided in the bottom portion, a plurality of protrusions protruding from the second surface are formed on the base portion, each of the plurality of fins is fixed to the base portion in a state where one of the plurality of protrusions is inserted into the through hole and the protrusion is plastically deformed, The heat sink according to any one of Claims 1 to 3.

6. The notch is provided at a position that does not interfere with the through hole, The heat sink according to Claim 5.

7. The plurality of fins have the same shape as each other, The heat sink according to any one of Claims 1 to 3.

8. The heat sink according to any one of Claims 1 to 3, and a light source module attached to the first surface of the base portion, comprising: A light source unit.

9. The light source unit according to Claim 8, and an appliance body for holding the light source unit, comprising: A lighting fixture.

Images