JP2013077470A - Lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lighting device of light weight and excellent in heat radiation.SOLUTION: For the lighting device provided with a platy part with a plurality of light-emitting elements fitted on the surface and a case body housing either a power source circuit supplying power to the light-emitting elements or a power source line connected to an outside power source, a through-hole is provided penetrating through the platy part, the light-emitting elements are arranged around the through-hole, a bottomless cylindrical vent part communicated with the through-hole is provided at the rear face, and a gap is fitted at an end part of the vent part to couple the case body, and the gap between the case body and the vent part is made open toward outside in a peripheral direction of the vent part.

Description

  The present invention relates to a lighting device suitable for use in a high ceiling lighting device.

  2. Description of the Related Art Conventionally, an indoor lighting device that illuminates by installing a high ceiling lighting device on an indoor ceiling of a factory, a gymnasium, a commercial facility, or the like is known (for example, see Patent Document 1).

JP 2009-301718 A

By the way, in recent years, in order to realize energy saving and long life of the high ceiling lighting device, it has been studied to use a light emitting element such as an LED as a light source of the lighting device. However, when a light emitting element such as an LED is used as a light source, it is necessary to efficiently dissipate heat generated by the light emitting element and the mounting substrate on which the light emitting element is mounted. Therefore, it is necessary to provide a heat radiating structure such as a heat radiating fin in the lighting device, and there is a problem that the weight of the lighting device increases.
The present invention is characterized in that it solves the problems of the above-described conventional technology, and provides a lighting device that is lightweight and excellent in heat dissipation.

  In order to achieve the above object, the present invention accommodates a plate-like portion provided with a plurality of light emitting elements on the surface, a power supply circuit for supplying power to the light emitting elements, or a power supply line connected to an external power supply. In a lighting device comprising a case body, a bottomless cylindrical shape in which a through-hole penetrating front and back is formed in the plate-like portion, the light-emitting element is disposed around the through-hole, and communicated with the through-hole The ventilation portion is provided on the back surface, a gap is provided at the end of the ventilation portion, the case body is connected, and the gap between the case body and the ventilation portion is opened to the outside in the circumferential direction of the ventilation portion. It is characterized by.

  In addition, the present invention provides a lighting device including a front cover that covers a surface of the plate-like portion and has an opening that engages with the through-hole, and that passes through the plate-like portion on the front and back sides. A ventilation duct is provided that forms an air hole and forms an air passage that leads to the gap at the end of the airflow portion from the airhole on the back surface of the plate-like portion between the airflow portion and the outer peripheral surface of the airflow portion. To do.

  Further, the present invention is characterized in that the front cover is provided with a vent hole in the above-described lighting device.

  Further, the present invention is characterized in that in the above-described lighting device, a plurality of heat radiation fins extending along the ventilation portion are provided on the back surface of the plate-like portion.

  In the illumination device according to the present invention, the case body includes an attachment unit that is detachably attached to an installation surface.

  According to the present invention, a plate-like portion having a plurality of light emitting elements provided on the surface, and a power supply circuit that supplies power to the light emitting elements, or a case body that houses a power supply line connected to an external power supply, are provided. In the lighting device, a through-hole penetrating front and back is formed in the plate-like portion, the light-emitting element is disposed around the through-hole, and a bottomless cylindrical ventilation portion communicating with the through-hole is provided on the back surface. Since the case body is connected by providing a gap at the end of the ventilation portion and the gap between the case body and the ventilation portion is opened to the outside in the circumferential direction of the ventilation portion, the through hole and the gap It is possible to reduce the material and reduce the weight, and further, an air flow is formed from the front side of the plate-like portion through the ventilation portion to the outside in the circumferential direction through the gap. Remove the heat of the light emitting element generated on the front side of the plate It can be released into, lightweight, and can provide an excellent illumination device heat dissipation.

It is a perspective view which shows the illuminating device which concerns on embodiment of this invention. It is a top view of an illuminating device. It is a disassembled perspective view of an illuminating device. It is a figure which shows the state of the illuminating device at the time of construction which attaches a case body to an attachment unit. It is sectional drawing of an illuminating device. It is a perspective view which shows the illuminating device which removed the front cover. FIG. 7A is a bottom view of the lighting device with the front cover removed, FIG. 7A shows a state in which only the mounting substrate and the light emitting element are provided, and FIG. 7B shows a state in which an insulating sheet is provided. FIG. 7C is a diagram showing a state where a reflecting mirror is provided.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating an aspect of a lighting device 1 according to the present embodiment. The lighting device 1 according to this configuration can be suitably used as a lighting device for a high ceiling that is used by being suspended from an indoor ceiling such as a factory, a gymnasium, or a commercial facility. In addition, in this embodiment, the upper and lower sides of the illuminating device 1 show the upper and lower sides of the illuminating device 1 in the state which installed the illuminating device 1 suspended from the ceiling.
The lighting device 1 includes a lamp body 10, a case body 30, and an attachment unit 40. The lamp body 10 is a light source unit of the illumination device 1 that includes a light emitting element 11 to be described later and that emits light emitted from the light emitting element 11 through a front cover (glove) 20.

  Although not shown, the lighting device 1 houses a power circuit inside the case body 30 and supplies power to the lamp body 10 through the power circuit. The lighting device 1 or a configuration in which a power line housed inside the case body 30 is connected to a power circuit provided outside the lighting device 1 and power is supplied to the lamp body 10 through the power line. There may be. The mounting unit 40 is provided in the case body 30 in order to mount the lighting device 1 on the installation surface. The lighting device 1 remains in a state where the mounting unit 40 is fixed to the installation surface, and the lamp body 10 and the case. The body 30 can be detachably attached from the attachment unit 40. The lamp body 10 is formed in a truncated cone shape in which the lower bottom of the irradiation opening 19 side is larger than the upper base, and the case body 30 does not impair continuity with respect to the diameter of the upper base of the lamp body 10. It is formed in a cylindrical shape having a diameter that can be connected to the lamp body 10. According to this configuration, the lamp body 10 and the case body 30 can be connected without impairing the design of the lighting device 1. Between the lamp body 10 and the case body 30, a gap S that opens in the outer circumferential direction is provided.

  The lamp body 10 includes a plate-like portion 13. A through hole 14 penetrating the plate-like portion 13 on the front and back sides is formed in the approximate center of the plate-like portion 13. The lamp body 10 includes a bottomless cylindrical ventilation portion 15 communicating with the through hole 14 on the back surface 13 </ b> B of the plate-like portion 13. The ventilation portion 15 communicates with the gap S between the lamp body 10 and the case body 30 and is opened in the outer peripheral direction of the lighting device 1 through the gap S. The lamp body 10 includes heat radiation fins 16 arranged along the ventilation portion 15 on the back surface 13B of the plate-like portion 13B. The radiating fins 16 are provided radially around the ventilation portion 15, and the outer peripheral side radiating fins 17 provided on the outer peripheral surface 15 </ b> A of the ventilation portion 15, the inner peripheral side radiating fins 18 provided on the inner peripheral surface 15 </ b> B, Is provided. The outer peripheral side heat radiating fins 17 are disposed on the outer peripheral side of the long fins 17A and are formed shorter than the long fins 17A. And comprising. Around the lighting device 1, a flow of air flowing from the lower side of the lamp body 10 through the ventilation portion 15 to the outer peripheral direction from the gap S is formed. Since the inner peripheral side radiating fin 18 is cooled by the flow of air passing through the ventilation portion 15, the heat inside the lamp body 10 can be efficiently radiated from the inner peripheral side radiating fin 18.

In order to reduce the weight of the lighting device 1, the heat radiation fins 16 are formed by die casting using a light metal such as aluminum or magnesium and excellent in heat dissipation. The radiating fin 16 has a plate-like shape in which the long fin 17A, the short fin 17B, and the inner peripheral radiating fin 18 are tapered in the molding direction, and the lower part is formed thicker than the upper part. It is provided to be perpendicular to the back surface 13 </ b> B of the part 13. According to this configuration, the radiating fins 16 including the long fins 17A, the short fins 17B, and the inner peripheral radiating fins 18 can be easily extracted from the mold during casting. Further, the long fins 17A and the short fins 17B are formed in a substantially right triangle shape along the outer peripheral surface 15A.
As shown in FIGS. 1 and 2, the outer peripheral side heat radiating fin 17 includes a connecting portion 17 </ b> C that connects the short fin 17 </ b> B and the long fin 17 </ b> A. The short fins 17B are formed such that the dimensions in the height direction H1 and the length direction L1 are shorter than the dimensions in the height direction H2 and the length direction L2 of the long fins 17A, and the connecting portion 17C has a short length. The fin 17B extends from the inner peripheral side end 17D to the adjacent long fin 17A. According to this configuration, by providing the connecting portions 17 </ b> C on the heat radiating fins 16, the heat radiating area of the heat radiating fins 16 can be increased.

A predetermined interval is provided between the adjacent long fins 17 </ b> A so that the heat dissipating fins 16 can be formed by die casting. Since the interval between the long fins 17A increases toward the outer peripheral side in the radial direction of the plate-like portion 13, the short fins 17B are provided on the outer peripheral side of the long fins 17A using this interval. Yes. According to this configuration, the heat radiation area can be increased and the heat radiation performance can be improved without impairing the castability of the heat radiation fins 16.
Further, by providing the connecting portion 17C that connects the short fin 17B and the long fin 17A, the fluidity of the metal material at the time of casting is improved, and the material flows to the thin portion at the upper end of the long fin 17A. Since it is improved, it is possible to prevent the molding failure of the long fins 17A.

  As shown in FIG. 1, the lamp body 10 includes a front cover 20 that covers the surface 13 </ b> A of the plate-like portion 13 in the irradiation opening 19. An opening 20 </ b> A that engages with the through hole 14 is formed in the front cover 20, and the opening 20 </ b> A communicates with the through hole 14 and the ventilation portion 15. The front cover 20 is provided with a vent 21 penetrating the front and back. A plurality of vent holes 21 are provided in the circumferential direction along the outer periphery of the front cover 20 and the opening 20A. From the vent hole 21, the air flows into the front cover 20 along the flow of air passing through the ventilation portion 15.

As shown in FIG. 3, the case body 30 includes a bottomed cylindrical case portion 31 and a connecting portion 33 that extends downward from the lower end portion 32 of the case portion 31. The case portion 31 includes a plurality of radiating fins 39 extending vertically along the outer peripheral surface and provided radially. When the power supply circuit is housed inside the case body 30, heat generated from the power supply circuit can be efficiently radiated to the outside by the heat radiation fins 39.
The connecting portion 33 includes four arms 33 </ b> A and 33 </ b> B provided on the outer peripheral surface of the case portion 31 at equal intervals in the circumferential direction. The arm 33 </ b> A is a fixing arm 33 </ b> A, and a fixing portion 35 for fixing the case body 30 to the lamp body 10 with a screw 34 is formed in a pair of opposing fixing arms 33 </ b> A. The arm 33B is a ventilation arm 33B to which a ventilation duct 22 of the lamp body 10 described later is connected. The pair of facing ventilation arms 33B are formed in a hollow bottomless shape, and the surface 36 that faces the gap S between the lamp body 10 and the case body 30 is opened. It is formed in a shape. A connector 37 to which a wiring extending from the lamp body 10 is connected is provided on the bottom surface 38 of the case body 30.

An attachment unit 40 is provided on the upper portion of the case body 30. The mounting unit 40 is fixed to the installation surface with screws or hanging hardware. A hook part 41 is provided at the upper end of the case body 30, and the attachment unit 40 is provided with a holding part 42 that holds the case body 30 by hooking the hook part 41.
As shown in FIG. 4, the case body 30 is connected to the lamp body 10 by a connecting portion 33, so that the lamp body 10 and the case body 30 can be detachably attached to the attachment unit 40. The mounting unit 40 can be fixed to the installation surface in advance, and the hook 10 is easily hooked to the holding portion 42 of the mounting unit 40 fixed to the installation surface in advance, so that the lamp 10 and the case can be easily attached. The body 30 can be integrally attached to the installation surface in a detachable manner.

  By the way, since the lighting device for high ceilings is a work in a high place, for example, a screw stop for fixing the lighting device to the installation surface with the other hand while holding the lighting device with one hand, etc. Installation work to perform was not easy. According to this configuration, the lamp body 10 and the case body 30 can be held and hooked together with the mounting unit 40 fixed in advance on the installation surface with both hands, and can be attached detachably. The installation work of the apparatus 1 can be performed easily and safely. The case body 30 and the mounting unit 40 are obtained by hooking the hook portion 41 of the case body 30 on the holding portion 42 of the mounting unit 40 fixed to the installation surface in advance, so that the lamp body 10 and the case body 30 are integrated. In the state where the mounting unit 40 is held, it is fixed with screws 51. According to this configuration, the lighting device 1 can be easily attached to the installation surface, and further, the case body 30 can be prevented from being detached from the attachment unit 40 after the lighting device 1 is attached to the installation surface. .

Further, the mounting unit 40 is provided with a wiring hole 48 provided on the surface facing the installation surface and penetrating the front and back surfaces, and the power line 49 (see FIG. 5) is connected to the lighting device 1 through the wiring hole 48. Connected.
As shown in FIG. 5, the lamp body 10 is provided with a light emitting element 11 on the surface 13 </ b> A of the plate-like portion 13. A plurality of light emitting elements 11 are arranged in the circumferential direction around a through hole 14 formed in the plate-like portion 13. A mounting board 12 is provided on the surface 13A of the plate-like portion 13 in a thermally connected manner, and the light emitting element 11 is mounted on the mounting board 12 and provided. A reflecting mirror 23 is provided in the space between the plate-like portion 13 and the front cover 20. The radiation direction of the light emitted from the light emitting element 11 can be set in an arbitrary direction by the reflecting mirror 23. In the present embodiment, as shown in FIG. 6, the reflecting mirror 23 is formed by arranging a large number of reflecting bodies 23A formed in a truncated quadrangular pyramid shape around the through-holes 14, and each reflecting body 23A is truncated. The light emitting element 11 is disposed in the portion 23B.

  Further, as illustrated in FIG. 5, the lamp body 10 includes a ventilation duct 22 that is connected to the gap S between the back surface 13 </ b> B of the plate-like portion 13 and the end portion 15 </ b> C of the ventilation portion 15. The ventilation duct 22 is connected to the ventilation arm 33B, and communicates with the gap S through the open surface 36 of the ventilation arm 33B. As shown in FIG. 7, a vent hole 26 penetrating the front and back is formed in the plate-like portion 13, and a vent duct 22 is connected to the vent hole 26. With this configuration, the lamp body 10 is connected to the outer peripheral surface 15 </ b> A of the ventilation portion 15 from the ventilation hole 26 of the plate-like portion 13 and to the gap S of the end portion 15 </ b> C of the ventilation portion 15 by the ventilation duct 22. Is formed. As described above, air flows into the inside of the front cover 20 from the vent 21 provided in the front cover 20, and therefore, this air enters the interior of the lamp body 10 through the ventilation hole 26 and the ventilation duct. A flow of air flowing through the gap S into the gap S is formed. According to this configuration, the heat generation from the light emitting element 11 and / or the mounting substrate 12 together with the air flow formed in the lamp body 10, the ventilation duct 22 and the ventilation arm 33 </ b> B from the ventilation hole 26. It is possible to dissipate heat from the gap S of the end portion 15C of the ventilation portion 15 through the air. Therefore, heat from the light emitting element 11 or the mounting substrate 12 is not exhausted to the inside of the lamp body 10 and is exhausted to the outside of the lighting device 1, so that the heat dissipation of the lamp body 10 can be improved. Furthermore, by forming the ventilation duct 22 in the lamp body 10, the lamp body 10 can be reduced in weight, and the effects of both the heat dissipation and the weight reduction of the lamp body 10 can be obtained at the same time.

  Further, the ventilation duct 22 can be used as a wiring path through which the electric wire 24 that supplies power to the light emitting element 11 is passed. The electric wire 24 is drawn through the inside of the ventilation duct 22 into the gap S of the end portion 15 </ b> C of the ventilation portion 15, and is connected to a connector 37 provided on the bottom surface 38 of the case body 30. According to this configuration, the electric wire 24 can be wired through the inside of the ventilation duct 22 without passing through the outside of the lamp body 10, and the design of the lighting device 1 can be improved. Furthermore, since the ventilation duct 22 can be used as a heat dissipation duct and a wiring duct, the casting cost of the lamp body 10 can be reduced.

  Further, as shown in FIG. 6, the outer peripheral surface 15 </ b> A of the ventilation portion 15 is provided with a connecting and fixing portion 27 having an appearance that is similar to the appearance of the ventilation duct 22. The connection fixing portion 27 is provided at a position corresponding to the fixing arm 33A when the ventilation duct 22 and the ventilation arm 33B are combined, and the upper end portion of the connection fixing portion 27 is as shown in FIG. In addition, a screwing portion 28 to which the screw 34 is screwed is formed. The fixing arm 33A and the coupling fixing portion 27 are configured such that the fixing portion 35 and the screwing portion 28 can be locked, and the fixing portion 35 and the screwing portion 28 are screwed together with screws 34. Thus, the lamp body 10 and the case body 30 can be fixed together.

FIG. 7 is a view of the illumination device 1 with the front cover 20 removed, as viewed from the irradiation surface side.
As shown in FIG. 7, the plate-like portion 13 is formed in an annular shape having a through hole 14 at the approximate center. As shown in FIG. 7A, the plate-like portion 13 includes a ventilation duct 22 that extends from the back surface 13 </ b> B of the plate-like portion 13 along the outer peripheral surface 15 </ b> A of the ventilation portion 15 and a connection fixing portion 27. It is divided into approximately four equal parts. On the surface 13A, a mounting substrate 12 formed in a substantially rectangular shape is disposed between each ventilation duct 22 and the connection fixing portion 27, and the light emitting element 11 is mounted on the mounting substrate 12 so as to face the irradiation opening 19. Yes. As the light emitting element 11, LED, organic EL, etc. can be used suitably. From the light emitting surface 11A side of the light emitting element 11, as shown in FIG. 7B, an insulating sheet 25 made of, for example, ceramic and provided with a hole 25A corresponding to the light emitting surface 11A is attached to the surface 13A. Further, as shown in FIG. 7C, the reflecting mirror 23 is fixed to the plate-like portion 13 with screws 28 with an insulating sheet 25 interposed therebetween.

  The connector 37 is provided on the bottom surface 38 of the case body 30, and the connection port 37 </ b> A of the connector 37 is open toward the ventilation portion 15. In order to increase the rigidity of the case body 30, a U-shaped metal fitting 46 having a substantially U-shaped cross section is provided on the bottom surface 38, and the U-shaped metal fitting 46 is provided inside the case body 30. A plurality of communication holes 47 that communicate with each other are provided. According to this configuration, heat generated from the power supply circuit or the like housed inside the case body 30 can be exhausted into the gap S between the case body 30 and the lamp body 10 through the communication hole 47. In addition, it is possible to prevent heat from getting inside the case body 30.

  As described above, according to the embodiment to which the present invention is applied, the plate-like portion 13 in which the plurality of light emitting elements 11 are provided on the surface 13A, the power supply circuit that supplies power to the light emitting elements 11, or the external power supply In a lighting device 1 including a case body 30 that houses a power supply line connected to the through hole 14, a through hole 14 that penetrates the plate-like portion 13 is formed in the plate-like portion 13, and the light emitting element 11 is disposed around the through hole 14. At the same time, a bottomless cylindrical ventilation portion 15 communicating with the through-hole 14 is provided on the back surface, and a gap S is provided at an end 15C of the ventilation portion 15 to connect the case body 30. The clearance gap S between them was opened to the outside in the circumferential direction of the ventilation portion 15. Thereby, by providing the through-hole 14, the ventilation part 15, and the clearance gap S, the material which forms the lamp 10 is reduced, and the illuminating device 1 can be reduced in weight. Further, since the ventilation portion 15 communicates with the outside in the circumferential direction through the gap S, it flows from the lower side of the lamp body 10 to the upper side through the ventilation section 15, and the gap S between the lamp body 10 and the case body 3. A flow of air that flows to the outside in the circumferential direction is formed. The lamp body 10 can be cooled by air cooling by this air flow, and the heat generated by the light emitting element 11 accommodated in the lamp body 10 can be efficiently dissipated. Therefore, it is possible to provide the lighting device 1 that is lightweight and excellent in heat dissipation.

  In addition, according to the embodiment to which the present invention is applied, the front cover 20 that covers the surface 13A of the plate-like portion 13 and has the opening 20A that engages with the through hole 14 is provided. A ventilation path is formed between the ventilation hole 15 on the back surface 13B of the plate-like portion 13 and the gap S between the end portion 15C of the ventilation portion 15 and the outer peripheral surface 15A of the ventilation portion 15. A ventilation duct 22 was provided. Thereby, without blocking the through hole 14 with the front cover 20, air can be flowed to the ventilation portion 15 through the opening 20 </ b> A and the through hole 14, and the lamp body 10 can be efficiently air-cooled by this air flow. it can. Further, the heat generation of the light emitting element 11 is efficiently carried out from the gap S through the ventilation hole 26 and the ventilation duct 22 without being trapped between the front cover 20 and the surface 13A of the plate-like portion 13. Since it can escape, the heat dissipation of the lamp 10 can be improved. Furthermore, since the ventilation duct 22 forms a hollow ventilation path with the outer peripheral surface 15A of the ventilation part 15, the weight of the lamp body 10 can be reduced. Further, since the ventilation duct 22 can be used as a wiring route for the electric wire 24 connected to the light emitting element 11, it is not necessary to separately provide a wiring duct for passing the electric wire 24, thereby reducing the cost during casting. Since the electric wire 24 can be wired without being visible on the appearance of the lighting device 1, the design of the lighting device 1 is also improved.

  Further, according to the embodiment to which the present invention is applied, since the vent hole 21 is provided in the front cover 20, air is caused to flow from the vent hole 21 to the inside of the front cover 20, and the vent duct 22 is provided inside the lamp body 10. Therefore, the heat generated from the light emitting element 11 does not enter the interior of the lamp body 10, and the air flows from the gap S through the ventilation duct 22 to the outside of the lighting device 1. Is exhausted. Thereby, the heat inside the lamp body 10 can be efficiently radiated.

  Further, according to the embodiment to which the present invention is applied, since the plurality of heat radiation fins 16 extending along the ventilation portion 15 are provided on the back surface 13B of the plate-like portion 13, the heat radiation area of the ventilation portion 15 can be increased. The heat dissipating property of the lighting device 1 can be enhanced by the heat dissipating fins 16.

  Moreover, according to the embodiment to which the present invention is applied, the case body 30 includes the attachment unit 40 that is detachably attached to the installation surface. Thereby, the attachment unit 40 can be fixed to the installation surface in advance, and the case body 30 can be easily and detachably attached to the attachment unit 40 while being held with both hands. Therefore, the illuminating device 1 attached to a high ceiling etc. can be attached easily and safely, and the workability of the illuminating device 1 can be improved.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to this. In the present embodiment, the inner peripheral radiating fin 18 is configured to be provided in parallel with the flow direction of the air flowing in the ventilation portion 15, but is not limited thereto, and becomes the ventilation resistance of the air flowing in the ventilation portion 15. Therefore, any shape and arrangement can be adopted as long as the heat radiation area of the ventilation portion 15 can be appropriately increased and can be molded without impairing the castability of the lamp body 10.

DESCRIPTION OF SYMBOLS 1 Illuminating device 3 Case body 10 Lamp body 11 Light emitting element 13 Plate-like part 13A Surface 13B Back surface 14 Through-hole 15 Ventilation part 15A Outer peripheral surface 15B Inner peripheral surface 15C End part 16 Radiation fin 17A Long fin 17B Short fin 20 Front cover 20A Opening 21 Ventilation hole 22 Ventilation duct 26 Ventilation hole 30 Case body 40 Mounting unit S Gap

Claims (5)

In a lighting device comprising: a plate-like portion provided with a plurality of light emitting elements on a surface; and a case body that houses a power supply circuit that supplies power to the light emitting elements or a power supply line connected to an external power supply.
A through-hole penetrating front and back is formed in the plate-like portion, the light-emitting element is disposed around the through-hole, and a bottomless cylindrical ventilation portion communicating with the through-hole is provided on the back surface. An illuminating device characterized in that a gap is provided at an end of the case to connect the case body, and a gap between the case body and the ventilation portion is opened to the outside in the circumferential direction of the ventilation portion. A front cover that covers the surface of the plate-like portion and has an opening that engages with the through hole;
A vent hole penetrating front and back is formed in the plate-like portion, and an air passage is formed between the vent hole on the back surface of the plate-like portion and the gap at the end of the ventilating portion with the outer peripheral surface of the ventilating portion. The lighting device according to claim 1, wherein a ventilation duct is provided.   The lighting device according to claim 2, wherein a vent hole is provided in the front cover. The lighting device according to claim 1, further comprising a plurality of heat radiation fins extending along the ventilation portion on a back surface of the plate-like portion.   The lighting device according to claim 1, wherein the case body includes an attachment unit that is detachably attached to an installation surface.

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