Lighting device

Abstract

To provide a lighting device that is compatible with thermal insulation construction and ensures heat dissipation. [Solution] The lighting device 10 comprises a base portion 21 to which a light source is attached on the front side, and a fin portion 22 provided on the back side of the base portion 21. The fin portion 22 is plate-shaped and rises from the back side of the base portion 21, and the spacing between the fin portions 22 located on the outer circumference of the base portion 21 is narrower than the spacing between the fin portions 22 located on the central side surrounded by the fin portions 22 on the outer circumference.

Description

Technical Field

[0001] Embodiments of the present invention relate to a lighting device.

Background Art

[0002] Conventionally, there is a lighting device such as a downlight that is embedded and installed in an embedding hole opened in a ceiling surface. In this lighting device, the heat generated by a light source unit disposed on the front side is radiated from a fin unit provided on the back side.

[0003] Also, when a high thermal resistance heat insulation construction is carried out by covering the ceiling surface with a heat insulating material such as shredded glass wool or cellulose fiber, if the fin unit of the lighting device is covered with the heat insulating material, sufficient heat dissipation by the fin unit may not be ensured.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The problem to be solved by the present invention is to provide a lighting device that can cope with heat insulation construction and ensure heat dissipation.

Means for Solving the Problems

[0006] The lighting device according to the embodiment includes a base unit to which a light source unit is attached on the front side, and a fin unit provided on the back side of the base unit. The fin unit is plate-shaped and rises from the back side of the base unit, and the interval between the fin units located on the outer periphery of the base unit is narrower than the interval between the fin units located on the central side surrounded by the fin units on the outer peripheral side.

Effects of the Invention

[0007] According to this embodiment, it is expected that the insulation work will be compatible with the construction and that heat dissipation will be ensured. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view of a lighting device showing one embodiment. [Figure 2] This is a plan view of the same lighting device. [Figure 3] This is a cross-sectional view of the same lighting device. [Modes for carrying out the invention]

[0009] One embodiment will be described below with reference to the drawings.

[0010] As shown in Figures 1 to 3, the lighting device 10 is a downlight that is embedded and installed in a recessed hole provided in a ceiling member such as a ceiling panel.

[0011] The lighting device 10 comprises a lamp body 11, a power supply unit 12 that supplies power to the lamp body 11, and wiring 13 that electrically connects the lamp body 11 and the power supply unit 12.

[0012] The light fixture 11 comprises a fixture body 16, a light source unit 17 disposed on the front side (bottom side) of the fixture body 16, and a plurality of mounting springs 19 attached to the outer surface of the fixture body 16.

[0013] The main body of the appliance 16 is made of a metal material with excellent thermal conductivity and heat dissipation, such as die-cast aluminum, and is integrally formed from it. The main body of the appliance 16 has a base portion 21 and a fin portion 22 provided on the back side (top side) of the base portion 21.

[0014] The base portion 21 includes a light source mounting portion 24 on which the light source portion 17 is installed, a conical cylindrical portion 25 that opens downward from the periphery of the light source mounting portion 24, and an annular decorative frame portion 26 that protrudes outward from the lower end of the cylindrical portion 25, with the inner lower surface of the decorative frame portion 26 being open. An annular packing 26a, for example made of silicone, is placed on the decorative frame 26 to contact the lower surface of the ceiling member.

[0015] The light source mounting section 24 of the base section 21 has a flat back section (top section) 27 and a side section 28 that protrudes downward from the periphery of the back section 27. The lower side of the back section 27 is formed as a flat light source mounting surface to which the light source section 17 is attached. The inner surface of the cylindrical section 25 is formed as a reflective surface that reflects light from the light source section 17 downward. The decorative frame section 26 abuts against the lower surface of the ceiling member around the mounting hole when the fixture is installed on the ceiling member, sandwiching the ceiling member between itself and the mounting spring 19 and covering the mounting hole.

[0016] The base portion 21 is provided with a plurality of spring mounting portions 29 for attaching the mounting spring 19 from the lower outer surface of the cylindrical portion 25.

[0017] The fin portion 22 has a plurality of outer peripheral fin portions 31 located on the outer circumference of the back side of the base portion 21, and a plurality of central fin portions 32 located on the central side surrounded by the outer peripheral fin portions 31. The outer peripheral fin portions 31 and the central fin portions 32 are thermally connected.

[0018] The outer fin portion 31 is plate-shaped and rises from the base portion 21, and is positioned radially from the center of the base portion 21 when viewed from the rear (the central axis of the base portion 21). The outer fin portion 31 rises from the base portion 21 from the peripheral area of ​​the rear portion 27 of the light source arrangement portion 24 to the intermediate area in the vertical direction of the cylindrical portion 25, and is thermally connected to the rear portion 27, the side portion 28, and the cylindrical portion 25.

[0019] The fin portion 32 on the central side is plate-shaped and rises from the base portion 21, and has a plurality of annular portions 33 positioned concentrically from the center (central axis of the base portion 21) in the rear view of the base portion 21, and a plurality of radial portions 34 positioned along the radial direction from the center to the outermost annular portion 33 in the rear view of the base portion 21. Each radial portion 34 is provided radially continuously with a part of the fin portion 31 on the outer peripheral side.

[0020] The interval between adjacent fin portions 31 on the outer peripheral side (the widest interval at the outermost diameter portion) is smaller than the interval between the fin portions 32 on the central side (the interval between adjacent annular portions 33, the widest interval between adjacent radial portions 34 between the annular portions 33). The widest interval at the outermost diameter portion of the fin portion 31 on the outer peripheral side is, for example, 4 to 6 mm, preferably about 5 mm.

[0021] A wiring drawing-in portion 37 into which the wiring 13 is drawn is provided in a part of the fin portion 31 on the outer peripheral side and the fin portion 32 on the central side, and a wiring cover 38 is screwed on the upper side of the wiring drawing-in portion 37.

[0022] The light source unit 17 has a light source module 40 which is a light source, and a lens 41 which controls the light from the light source module 40.

[0023] The light source module 40 is configured by mounting a plurality of surface-mounted light-emitting elements 43 such as LEDs, for example, on the front side of the substrate 42. The light source module 40 may be a COB (Chip On Board) module in which a plurality of LEDs mounted on the substrate are sealed with a phosphor layer. The back side of the substrate 42 is attached in a state of being thermally connected to the light source arrangement portion 24 of the base portion 21 via a heat conduction member such as a heat conduction sheet. A wiring 13 drawn into the base portion 21 from the wiring drawing-in portion 37 is connected to the light source module 40, and lighting power is supplied from the light source unit 12 to light the light-emitting element 43.

[0024] The lens 41 is detachably attached to the side portion 28 of the light source arrangement portion 24 of the base portion 21, and is positioned opposite the light source module 40, controlling the light from the light source module 40 that is irradiated to the outside to a predetermined light distribution.

[0025] Furthermore, the mounting spring 19 is, for example, a leaf spring, with one end attached to the spring mounting portion 29 of the base portion 21 and the other end protruding so as to extend laterally from the base portion 21.

[0026] Furthermore, the power supply unit 12 is separately positioned on the upper surface of the ceiling member and is electrically connected to the light source module 40 of the light source unit 17 via wiring 13. The power supply unit 12 includes a power supply circuit board (not shown) on which power supply circuit components are mounted to form a power supply circuit, a power supply case 53 that houses the power supply circuit board, and a terminal block 54 for connecting external power lines. The power supply circuit converts the AC power supplied through the power lines into a predetermined DC power, which is lighting power, and supplies it to the light source module 40 of the light source unit 17 to light up the light-emitting element 43.

[0027] To install the lighting device 10, power lines are pulled downwards from the recessed holes in the ceiling member and connected to the terminal block 54 of the power supply unit 12, and the power supply unit 12 is inserted into the recessed holes from below and placed on the upper surface of the ceiling member.

[0028] Each mounting spring 19 is elastically deformed against the spring force so that it follows the side surface of the fin portion 22, and then inserted into the embedded hole of the ceiling member from below. By releasing the deformation of the mounting spring 19, each mounting spring 19 expands laterally to the base portion 21 by the spring force and engages with the upper surface of the ceiling member, and the fixture body 16 is pulled up, and the fixture is clamped to the ceiling member between each mounting spring 19 and the decorative frame portion 26 that abuts the lower surface of the ceiling member, thus completing the installation.

[0029] Furthermore, when the lighting device 10 is turned on, the heat generated by the light-emitting element 43 of the light source unit 17 is transferred to the base unit 21, then from the base unit 21 to the fin unit 22 (the outer fin unit 31 and the central fin unit 32), and from the fin unit 22 the heat is dissipated into the air.

[0030] The heat generated by the light-emitting element 43 of the light source unit 17 is mainly transferred to the central area of ​​the back surface 27 of the base unit 21, and then spreads from the central area of ​​this back surface 27 to the peripheral area, and further to the side surface 28 and the cylindrical part 25.

[0031] As heat is transferred to the outer fin portion 31 and its temperature rises, the warmed air surrounding the outer fin portion 31 rises, and cooler air flows in between the outer fin portion 31 from the outside, creating convection where air rises between the outer fin portion 31. This air convection allows for efficient heat dissipation from the outer fin portion 31.

[0032] The heat transferred to the rear section 27 is also transferred to the central fin section 32, and heat is dissipated into the air from the central fin section 32. Although there is little air convection in the central fin section 32, some of the heat transferred to the central fin section 32 is transferred to the thermally connected outer fin section 31, and heat is dissipated into the air from the outer fin section 31.

[0033] Furthermore, when insulation is installed on ceiling components, the entire ceiling component is covered with insulation material. For high thermal resistance insulation, insulation materials such as defibrated glass wool are used, and the insulation material is sprayed onto the ceiling component and piled up to a predetermined height. When the insulation material is defibrated glass wool, the smallest thickness is about 8 mm.

[0034] The insulation material is also applied to the lighting fixture 10 installed on the ceiling member, so that the lighting fixture 10 is covered with the insulation material.

[0035] This insulation construction causes the insulation material to penetrate between adjacent fin sections 22, obstructing the airflow caused by convection between the fin sections 22, which reduces heat dissipation.

[0036] In the lighting device 10 of this embodiment, the spacing between the fin portions 31 on the outer periphery is narrower than the spacing between the fin portions 32 on the central side, which reduces the amount of heat-insulating material that gets into the spaces between the fin portions 31 on the outer periphery. The fin portions 31 on the outer periphery have a higher heat dissipation effect because cooler air from the outside flows in through convection compared to the fin portions 32 on the central side. By reducing the amount of heat-insulating material that gets into the spaces between the fin portions 31 on the outer periphery, sufficient heat dissipation can be ensured.

[0037] The spacing between the fin portions 31 on the outer circumference is, for example, 4 to 6 mm, preferably about 5 mm. In the case of defibrated glass wool insulation, the spacing is as small as 8 mm, so this reduces the amount of insulation that gets into the spaces between the fin portions 31 on the outer circumference.

[0038] Since the central fin section 32 is thermally connected to the outer fin section 31, even if the heat dissipation performance of the central fin section 32 is lower than that of the outer fin section 31, the heat from the central fin section 32 can be transferred to the outer fin section 31 for heat dissipation, thereby improving the overall heat dissipation performance.

[0039] According to JIS 5002, a standard set by the Japan Lighting Manufacturers Association, the thermal resistance value of downlights suitable for insulated installations is 6.6 m². 2 Although it is specified up to kW, the lighting device 10 of this embodiment has a limit of 10 m 2 It becomes possible to handle thermal resistance values ​​of approximately kW / W. Furthermore, the energy-saving standard ZEH (registered trademark) requires a thermal resistance value of 15m 2 The thermal resistance value is specified as kW / W, and this can be addressed by extending the fin section 22 radially and upward to increase its surface area.

[0040] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of symbols]

[0041] 10 Lighting devices 17 Light source section 21 Base section 22 Fin section

Claims

1. A base part to which the light source is attached on the front side; The fin portion provided on the rear side of the base portion; Equipped with, The fin portion is plate-shaped and rises from the back side of the base portion, and the spacing between the fin portions located on the outer circumference of the base portion is narrower than the spacing between the fin portions located on the central side surrounded by the fin portions on the outer circumference. A lighting device characterized by the following features.

2. The fin portion on the outer periphery and the fin portion on the central side are thermally connected. The lighting device according to feature 1.

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