Lighting fixtures

Abstract

To provide a lighting fixture that easily emits bright illumination light and is less prone to thermal degradation of its components. [Solution] The lighting fixture comprises a fixture body having a through hole in the center, a substrate 15 arranged around the through hole of the fixture body, a plurality of light-emitting elements 30 mounted on the lower surface 15c of the substrate 15 so as to surround the through hole, and a resin sheet covering the light-emitting side of the plurality of light-emitting elements 30. The plurality of light-emitting elements 30 include a plurality of first light-emitting elements 30a and a plurality of second light-emitting elements 30b arranged at a lower density than the plurality of first light-emitting elements 30a.

Description

Technical Field

[0001] The present disclosure relates to a lighting fixture.

Background Art

[0002] Conventionally, as a lighting fixture, there is a ceiling light described in Patent Document 1. This ceiling light includes a fixture main body having a through hole in a central portion, a substrate fixed to the fixture main body and having a through hole in a central portion, a plurality of LEDs mounted on the substrate, and a diffusion cover that covers a light emission side of the plurality of LEDs and is substantially circular in a plan view when viewed from a height direction.

Prior Art Literature

Patent Literature

[0003]

Patent Literature 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] Increasing the number of light-emitting elements mounted on a substrate facilitates emission of bright illumination light. However, if a plurality of light-emitting elements are arranged at an excessively high density, components constituting the lighting fixture, for example, the light-emitting elements themselves, are likely to undergo thermal degradation due to heat generated by the light-emitting elements. Accordingly, an object of the present disclosure is to provide a lighting fixture that easily emits bright illumination light and is less likely to cause thermal degradation of components.

Means for Solving the Problem

[0005] To solve the above problem, a lighting fixture according to the present disclosure includes: a fixture main body provided with a through hole in a central portion; a substrate arranged around the through hole of the fixture main body; a plurality of light-emitting elements mounted on one side surface of the substrate so as to surround the through hole; and a light projection portion covering the light emission side of the plurality of light-emitting elements, wherein the plurality of light-emitting elements include a plurality of first light-emitting elements and a plurality of second light-emitting elements arranged at a lower density than the plurality of first light-emitting elements. [Effects of the Invention]

[0006] According to the lighting fixture described herein, it is easy to emit bright illumination light, and thermal degradation of components is less likely to occur. [Brief explanation of the drawing]

[0007] [Figure 1] This is a perspective view of a lighting fixture according to one embodiment of the present disclosure, as seen from a diagonally downward angle. [Figure 2] This is a perspective view of the lighting fixture with the diffuser cover removed, seen from a diagonal downward angle. [Figure 3] This is a perspective view of the lighting fixture from a diagonal downward angle, with the power supply cover, which further protects the electronic components, removed from the state shown in Figure 2. [Figure 4] This is a perspective view showing the state after the translucent resin sheet covering the substrate has been removed from the state shown in Figure 3. [Figure 5] This is a perspective view showing the state after the reflective sheet has been removed from the state shown in Figure 4. [Figure 6] This is a plan view of a circuit board on which multiple power supply components, multiple first light-emitting elements, and second light-emitting elements are mounted, as seen from below in the height direction. [Figure 7] This is a perspective view of the first protective cover, taken from a diagonal downward angle in the height direction. [Figure 8] This is a perspective view of the first protective cover, taken from an oblique upward angle in the height direction. [Figure 9] This perspective view is achieved assuming that the second protective cover is no longer visible from the state shown in Figure 2. [Figure 10] This is a perspective view of the movement restricting member, seen from an oblique angle above. [Figure 11] This is a perspective view of the second protective cover, seen from a diagonal downward angle. [Figure 12] This is a perspective view of the second protective cover, seen from an oblique angle above. [Figure 13] This is a perspective view illustrating the relative position of some of the power lines to the second protective cover. [Figure 14] This is a plan view showing a portion of a circuit board on which multiple light-emitting elements are mounted in the first reference example lighting fixture. [Figure 15] This is a plan view showing the arrangement structure of multiple lenses in a lighting fixture, which is the second reference example. [Figure 16] This is a plan view of the resin sheet as seen from below in the height direction. [Modes for carrying out the invention]

[0008] The embodiments relating to this disclosure will be described in detail below with reference to the accompanying drawings. Note that if multiple embodiments or modifications are included below, it is intended from the outset that new embodiments may be constructed by appropriately combining their characteristic features. In the following embodiments, the same reference numerals are used for the same components in the drawings, and redundant explanations are omitted. Furthermore, multiple drawings include schematic diagrams, and the dimensional ratios such as length, width, and height of each component do not necessarily match between different drawings. The numerous components described below include several optional components that are not essential. Also, in this specification, the term "omitted" may be used to allow for manufacturing tolerances (manufacturing variations), and may be used to describe the general shape of components, etc.

[0009] In the following description, when terms related to the vertical direction such as down, up, lower side, and upper side are used, they indicate the direction when the lighting fixture 1 is installed on the ceiling. Also, when the height direction is mentioned in the following description, that height direction refers to the height direction of the lighting fixture 1, and when the orthogonal direction is mentioned, that orthogonal direction refers to the direction perpendicular to the height direction. In this embodiment, the lighting fixture 1 is installed on the ceiling with its height direction approximately coinciding with the vertical direction.

[0010] The lighting fixture 1 of the embodiment has a shape whose center and radial direction can be identified in a plan view when viewed from the lower side in the height direction. More specifically, the diffusion cover 50 of the embodiment has a dome shape and a substantially circular shape in a plan view when viewed from the lower side in the height direction. In the following description, when the radial direction is referred to, the radial direction indicates the radial direction of the diffusion cover 50; when the inner side is referred to, the inner side indicates the radially inner side; when the outer side is referred to, the outer side indicates the radially outer side. The central axis of the lighting fixture 1 coincides with the central axis of the diffusion cover 50.

[0011] FIG. 1 is a perspective view of the lighting fixture 1 according to one embodiment of the present disclosure when viewed obliquely from below. The lighting fixture 1 is a ceiling light and is attached to the ceiling of a building. Although not described in detail because it is a well-known structure, the lighting fixture 1 includes an adapter (not shown) that is attached to a fixture attachment portion (not shown) provided on the ceiling of a building. The lighting fixture 1 further includes: a fixture main body (base member) 10 that is stationary relative to the adapter and disposed along the ceiling substantially parallel to the ceiling; a light-emitting portion 20 (see FIGS. 4 and 5) that is stationary relative to the fixture main body 10; and a diffusion cover 50 that is disposed so as to cover the light-emitting portion 20 and constitutes a translucent cover.

[0012] The fixture main body 10 is made of metal or resin. The diffusion cover 50 has a downwardly convex dome shape and a substantially circular shape in a plan view when viewed from the lower side in the height direction. The diffusion cover 50 is made of a translucent resin material such as polycarbonate, acrylic, silicone, or the like, and diffuses light from the light-emitting portion 20 and emits the light downward. In the present embodiment, the light-emitting portion 20 emits light based on electric power supplied from the outside through the adapter, but the light-emitting portion 20 may emit light based on electric power supplied from the outside without passing through the adapter.

[0013] FIG. 2 is a perspective view of the lighting fixture 1 with the diffusion cover 50 removed, as viewed obliquely from below. As shown in FIG. 2, the lighting fixture 1 has a plurality of receivers 40 attached to the lower surface 10a of the fixture body 10 via locking (hooking), screwing or the like in a state arranged at substantially equal intervals in the circumferential direction. Each receiver 40 has a recess 41 opening radially outward. The radial direction is included in the orthogonal direction. The diffusion cover 50 has a plurality of protrusions (not shown) protruding radially inward on the inner circumferential surface of the upper edge. The plurality of protrusions are arranged on the diffusion cover 50 at substantially equal intervals in the circumferential direction. A part of the inner surface of the recess 41 is defined by a locking portion (not shown) that protrudes radially outward to lock the protrusion.

[0014] In a state where the circumferential position of each protrusion is different from the circumferential position of the corresponding receiver 40, the diffusion cover 50 is brought into contact with the lower surface 10a of the fixture body 10 so as to cover the plurality of receivers 40. Subsequently, when the diffusion cover 50 is relatively rotated to one side in the circumferential direction with respect to the fixture body 10, the diffusion cover 50 is elastically deformed radially outward, so that the tapered tip end of the protrusion rides over the locking portion, and the protrusion fits into the recess 41. By this fitting, the protrusion is locked to the locking portion, and the diffusion cover 50 is fixed to the plurality of receivers 40.

[0015] FIG. 3 is a perspective view of the lighting fixture 1 with the power cover 45 that protects power supply components 5 further removed from the state shown in FIG. 2, as viewed obliquely from below. As shown in FIG. 3, the outer edge of the fixture body 10 has a substantially circular shape, and a through hole 11 is provided in the central portion of the fixture body 10. In the present embodiment, the through hole 11 is a cylindrical hole. The lighting fixture 1 includes a substrate 15 sandwiched between a resin sheet 35 described later and the lower surface 10a of the fixture body 10 at a radially inner central portion. The substrate 15 does not need to be fixed by being sandwiched, and may be attached to the lower surface 10a of the fixture body 10 by a fixing means such as a screw, an adhesive or the like.

[0016] In this embodiment, when viewed from the height direction (thickness direction of the substrate 15), the substrate 15 has a substantially rectangular outer edge 15a. Here, a substantially rectangular shape is a shape whose general shape is rectangular, and a substantially rectangular shape includes shapes in which the corners are notched by chamfering or the like compared to a rectangle, and further includes shapes in which at least one of a recess and a protrusion is provided at one or more locations on the outer edge of the side. When viewed from the height direction (thickness direction of the substrate 15), the outer edge of the substrate may have a shape other than a substantially rectangular shape, for example, it may have a shape such as a substantially square, substantially circular, or substantially elliptical. The substrate 15 has a through hole 15b in the center. In this embodiment, the through hole 15b is a cylindrical hole. The through hole 15b is provided at a position that overlaps with the through hole 11 in the height direction. The central axis of the through hole 11, the central axis of the through hole 15b, and the central axis of the lighting fixture 1 are located on substantially the same straight line.

[0017] Multiple power supply components 5 are mounted in the area surrounding the through-hole 15b on the lower surface (mounting surface) 15c of the substrate 15. The lower surface 15c constitutes one side surface. The multiple power supply components 5 consist of electronic components included in at least one of a power supply device that supplies power to the light-emitting unit 20 and a control device that controls the light emission of the light-emitting unit 20. Here, light emission control refers to control related to the light emission of the light-emitting unit 20, and light emission control includes dimming control, color adjustment control, and control of turning on or off. The power supply device converts AC power from an external source into DC power and steps it down to an appropriate voltage. The control device controls the turning on and off of the lighting fixture 1.

[0018] For example, when the control device receives a wireless signal from a remote control (not shown) indicating that the light-emitting element (see Figure 4) 30 is turned on, it turns on the switching unit for controlling the light source of the light-emitting element 30 mounted on the power supply unit. Conversely, when the control device receives a wireless signal from the remote control indicating that the light-emitting element 30 is turned off, it turns off the switching unit for controlling the light source of the light-emitting element 30. When the unit is turned on, power is supplied to the light-emitting element 30 and light is emitted from the light-emitting element 30. When the unit is turned off, power to the light-emitting element 30 is cut off and light is no longer emitted from the light-emitting element 30. The switching unit is composed of, for example, a transistor.

[0019] As shown in Figure 2, the light-emitting sides of multiple power supply components 5 are covered with a power supply cover 45 to prevent electric shock. The fixing structure of the power supply cover 45 to the fixture body 10 will be described in detail later. The light-emitting sides of multiple light-emitting elements 30 on the substrate 15 are covered with a translucent resin sheet 35. The resin sheet 35 is an example of a translucent part. By covering the multiple light-emitting elements 30 with an insulating resin sheet 35, electric shock can be prevented. The resin sheet 35 is substantially similar to the substrate 15 when viewed from the height direction and has a substantially rectangular outer edge that is larger than the substrate 15. The resin sheet 35 includes a cylindrical hole 35a in the center and notches 35b that communicate with the cylindrical hole 35a and are located at substantially equal intervals in the circumferential direction. The resin sheet 35 is formed, for example, by injection molding and is made of polycarbonate, acrylic, or silicone.

[0020] The resin sheet 35 is positioned on the light-emitting side of the multiple light-emitting elements 30 and includes multiple lenses 55 that correspond one-to-one with the multiple light-emitting elements 30, with the distance between the light-emitting elements 30 being greater than or equal to the diameter of the lenses 55. In this embodiment, all the lenses 55 are included in the resin sheet 35 and are integrally connected. Each lens 55 is positioned so as to overlap one of the light-emitting elements 30 when viewed from the height direction.

[0021] Figure 4 is a perspective view showing the state in which the translucent resin sheet 35 covering the substrate 15 has been removed from the state shown in Figure 3. As shown in Figure 4, the light-emitting unit 20 is equipped with a plurality of light-emitting elements 30. The lighting fixture 1 also has a reflective sheet 25. The reflective sheet 25 is sandwiched between the substrate 15 and the resin sheet 35. The reflective sheet 25 is a sheet-like material with a higher reflectivity to light than the substrate 15, and reflects light that is directed directly from the light-emitting elements 30 to the reflective sheet 25, as well as light that is directed indirectly from the light-emitting elements 30 to the reflective sheet 25. The reflective sheet 25 has a cylindrical hole 25a in the center and a plurality of notches 25b that communicate with the cylindrical hole 25a and are located at approximately equal intervals in the circumferential direction. The plurality of notches 25b correspond to the notches 35b of the resin sheet 35, and the notches 25b include portions that overlap the notches 35b in the height direction.

[0022] Examples of the reflective sheet 25 include polyester film. The reflective sheet 25 plays a role in increasing the light extraction efficiency of each light-emitting element 30. Through holes (not shown) are provided at the positions where each light-emitting element 30 is positioned on the reflective sheet 25. Note that the lighting fixture of this disclosure does not necessarily have a reflective sheet. The resin sheet 35 is fixed to the fixture body 10 with screws in a state where the notch 35b overlaps the notch 25b when viewed from the height direction. In this embodiment, the resin sheet 35 is fixed to the fixture body 10 with screws, but the resin sheet 35 may also be fixed to the fixture body 10 with adhesive, or fixed to the outer edge of the substrate 15 with screws or adhesive.

[0023] Figure 5 is a perspective view showing the state in which the reflective sheet 25 has been removed from the state shown in Figure 4, and Figure 6 is a plan view of the substrate 15 on which multiple power supply components 5, multiple first light-emitting elements 30a, second light-emitting elements 30b, and third light-emitting elements 16 are mounted, as viewed from below in the height direction. As shown in Figure 6, the multiple light-emitting elements 30 include multiple first light-emitting elements 30a and multiple second light-emitting elements 30b arranged at a lower density than the multiple first light-emitting elements 30a. The first light-emitting elements 30a are light-emitting elements 30 located in the region R1 enclosed by the dotted line in Figure 6, and the second light-emitting elements 30b are light-emitting elements 30 located in the region R2 enclosed by the dashed line in Figure 6.

[0024] Multiple first light-emitting elements 30a are mounted on the substrate 15 in a honeycomb arrangement, where, in a plan view from the height direction, the center of one first light-emitting element 30a is located at the position of each vertex of an equilateral triangle with the same side length, as if the substrate were tiled without gaps. On the other hand, multiple second light-emitting elements 30b are mounted on the substrate 15 in a grid arrangement, where, in a plan view from the height direction, the center of one second light-emitting element 30b is located at the position of each vertex of a square, as if the substrate were tiled without gaps.

[0025] In this embodiment, the substrate 15 has a roughly rectangular outer edge 15a when viewed from the height direction, and a portion of the multiple first light-emitting elements 30a are arranged at both ends in the width direction of the substrate 15 at the center of the longitudinal direction of the substrate 15 (the region R3 enclosed by the dashed line in Figure 5). As shown in Figures 5 and 6, the lighting fixture 1 includes a third light-emitting element 16 mounted on the lower surface 15c of the substrate 15. The third light-emitting element 16 constitutes the light source of the night light. The multiple light-emitting elements 30 are arranged outside the multiple power supply components 5 and the third light-emitting element 16 so as to surround the multiple power supply components 5 and the third light-emitting element 16.

[0026] In this embodiment, the light-emitting element 30 and the third light-emitting element 16 are composed of LED (light-emitting diode) chips. However, the light-emitting elements mounted on the substrate may be composed of semiconductor laser element chips or the like, or of semiconductor light-emitting element chips other than LED chips. Alternatively, the light-emitting elements mounted on the substrate may be composed of organic EL (Electro-Luminescence) elements or inorganic EL elements or the like.

[0027] Next, the structure of the power supply cover 45 will be described in detail. Referring to Figure 2, the power supply cover 45 defines a donut-shaped chamber 18 that is sealed on the lower side in the height direction. The power supply cover 45 has a first protective cover 60 and a second protective cover 70. Figure 7 is a perspective view of the first protective cover 60 as seen from the lower side in the height direction, and Figure 8 is a perspective view of the first protective cover 60 as seen from the upper side in the height direction.

[0028] As shown in Figure 7, the first protective cover 60 is an annular, integral resin member and has a first through-hole 61 in its center, which is a substantially cylindrical hole. The first protective cover 60 also has a second through-hole 62 located between the first through-hole 61 and the outer edge 67 in a part of its circumferential direction. The first protective cover 60 has a fixing piece 64 that protrudes radially outward from the annular wall portion 63 defining the first through-hole 61 toward the second through-hole 62. The fixing piece 64 is provided with a screw hole 64a and a mounting base 64c including a through-hole 64b. A movement restricting member 85 (see Figures 9 and 10) is placed on the mounting base 64c.

[0029] As shown in Figure 7, the outer surface of the first protective cover 60 has one or more second protrusions 68 that project outward along the power supply component 5, and in this embodiment, there are multiple second protrusions 68. Also, as shown in Figure 8, the inner surface of the first protective cover 60 has recesses 69 at locations corresponding to each second protrusion 68. A part of the corresponding power supply component 5 is housed in the recesses 69. By adopting this configuration, the power supply cover 45 can be made compact, so that the light emitted from the light-emitting element 30 toward the center is less likely to be reflected or absorbed by the power supply cover 45 and more likely to pass outside the power supply cover 45. Therefore, a bright and clean illumination light can be emitted with a bright central part.

[0030] Figure 9 is a perspective view assuming that the second protective cover 70 is no longer visible from the state shown in Figure 2, and Figure 10 is a perspective view of the movement restricting member 85 viewed from diagonally above. Figure 11 is a perspective view of the second protective cover 70 viewed from diagonally below, and Figure 12 is a perspective view of the second protective cover 70 viewed from diagonally above. As shown in Figure 9, when the second protective cover 70 is removed from the power supply cover 45, the third light-emitting element 16 mounted on the substrate 15 becomes visible when viewed from the height direction. As shown in Figures 9 and 10, the movement restricting member 85 has a substantially L-shaped housing recess 85a for housing the power supply line 81, and the power supply line 81 is housed in the housing recess 85a.

[0031] As shown in Figure 10, the movement restricting member 85 has a pair of locking portions 85b at its upper end. On the other hand, as shown in Figure 11, the second protective cover 70 has a groove 70a that extends in the height direction and has a closed lower end, and as shown in Figure 12, it has a pair of projections 70b at its upper end. By engaging a pair of locking claws 85c provided on the tip side of the pair of locking portions 85b with the outer side surfaces 70c of the pair of projections 70b, the movement restricting member 85 and the second protective cover 70 are integrated into one unit.

[0032] During this integration, the approximately L-shaped opening of the approximately L-shaped receiving recess 85a is closed by the groove 70a. The movement restricting member 85 and the second protective cover 70 work together to define an approximately L-shaped passage. A portion of the power line 81 is constrained by being housed within this approximately L-shaped passage, thereby restricting the movement of a portion of the power line 81. As shown in Figure 13, the second protective cover 70 has a movement restricting portion 70d positioned circumferentially apart from the groove 70a, and the movement restricting portion 70d includes a first plate portion 73a extending approximately in the height direction and a second plate portion 73b projecting radially inward from the lower end of the first plate portion 73a. A portion of the power line 81 is hooked onto the upper side of the second plate portion 73b.

[0033] As shown in Figure 13, the power supply line 81 extends from the power supply unit, passes through a roughly L-shaped passage, and then extends from the lower opening of the roughly L-shaped passage, through the upper side of the second plate portion 73b, to the adapter attached to the fixture mounting portion on the ceiling. By restricting the position of the power supply line 81 with the roughly L-shaped passage and the movement restricting portion 70d, the excess portion of the power supply line 81 is effectively constrained, and the reflection of the power supply line 81 in the illumination light is suppressed.

[0034] As shown in Figure 2, the first protective cover 60 has a plurality of first protrusions 65 that are spaced apart in the circumferential direction on the peripheral edge of the upper end and protrude radially outward. The first protrusions 65 have through holes 65a that extend in the height direction. When viewed from the height direction, the first protrusions 65 have a planar shape corresponding to the notches 35b and 25b and overlap the notches 35b and 25b in the height direction. The first protrusions 65 include portions that are located inside the notches 35b and 25b. The first protective cover 60 is screw-fixed to the device body 10 with the substrate 15 sandwiched between the through holes 65a.

[0035] The second protective cover 70 is fitted into the second through-hole 62 of the first protective cover 60 so as to cover the light-emitting side of the second through-hole 62. As shown in Figure 11, the second protective cover 70 has a plate portion 70e that extends substantially perpendicularly and includes a portion located between the groove portion 70a and the movement restricting portion 70d in the circumferential direction. The plate portion 70e has a screw hole 70f. With the second protective cover 70 fitted into the second through-hole 62, the screw hole 70f of the second protective cover 70 overlaps in the height direction with the screw hole 64a (see Figure 7) of the fixing piece 64 of the first protective cover 60. The second protective cover 70 is fixed to the first protective cover 60 and the device body 10 by inserting the shaft of a screw (not shown) through the screw hole 70f and the screw hole 64a and then tightening it into the device body 10.

[0036] As shown in Figures 11 and 12, the second protective cover 70 has a lens 71. When the second protective cover 70 is fixed to the first protective cover 60 and the main body 10, the optical axis of the third light-emitting element 16 is located substantially on the same line as the central axis of the lens 71. The second protective cover 70 is made of a transparent resin material, such as transparent acrylic, transparent polycarbonate, or transparent silicone-based resin material, or transparent glass material. On the other hand, the first protective cover 60 is made of a white resin material. Polycarbonate or polybutylene terephthalate can be suitably used as the resin material constituting the first protective cover 60.

[0037] By constructing the second protective cover 70 from a transparent material, light emitted downwards in the height direction from the third light-emitting element 16 passes through the lens 71 and the diffusion cover 50 and is emitted downwards. Furthermore, by constructing the first protective cover 60, which occupies most of the power supply cover 45, from a white resin material, the reflectivity of the light emitted from the light-emitting element 30 and reaching the first protective cover 60 can be increased. Therefore, the light extraction efficiency can be increased, and bright illumination light can be easily emitted.

[0038] Next, the effects of the lighting fixture 1 of this disclosure will be explained. Figure 14 is a plan view showing a part of the substrate 115 on which multiple light-emitting elements 130 are mounted in the lighting fixture of the first reference example. As shown in Figure 14, when multiple light-emitting elements 130 with uneven spacing are mounted on the substrate 115, it is difficult for bright and evenly luminous illumination light to be emitted from the lighting fixture. In addition, while increasing the number of light-emitting elements mounted on the substrate makes it easier for bright illumination light to be emitted, if multiple light-emitting elements are arranged at an excessively high density, the heat generated by the light-emitting elements makes the components constituting the lighting fixture, such as the light-emitting elements, more susceptible to thermal degradation.

[0039] In contrast, the lighting fixture 1 of the present disclosure comprises a fixture body 10 having a through hole 11 in the center, a substrate 15 arranged around the through hole 11 of the fixture body 10, a plurality of light-emitting elements 30 mounted on the lower surface 15c of the substrate 15 so as to surround the through hole 11, and a resin sheet 35 covering the light-emitting side of the plurality of light-emitting elements 30, wherein the plurality of light-emitting elements 30 include a plurality of first light-emitting elements 30a and a plurality of second light-emitting elements 30b arranged at a lower density than the plurality of first light-emitting elements 30a.

[0040] Therefore, by appropriately arranging a high-density light-emitting region where multiple first light-emitting elements 30a are arranged and a low-density light-emitting region where multiple second light-emitting elements 30b are arranged in a balanced manner according to the specifications of the lighting fixture 1, it is possible to simultaneously achieve the emission of bright illumination light and suppression of thermal degradation of components, which are in a trade-off relationship with each other.

[0041] In a plan view from the height direction, the multiple first light-emitting elements 30a may be mounted on the substrate 15 in a honeycomb arrangement such that the center of one first light-emitting element 30a is located at the position of each vertex of an equilateral triangle, when multiple equilateral triangles with the same side length are arranged without gaps.

[0042] A honeycomb arrangement can also be defined as an arrangement in which, when multiple identical regular hexagons are laid out without gaps on the same plane, the center of one first light-emitting element 30a is located at the position of each vertex of the regular hexagon, and the center of one first light-emitting element 30a is also located at the center position of the regular hexagon.

[0043] With this configuration, the distance between two adjacent first light-emitting elements 30a can be made the same in all directions, and multiple first light-emitting elements 30a can be arranged particularly closely together. Therefore, the brightness of the light emitted from the high-density arrangement region of light-emitting elements can be increased.

[0044] In a plan view from the height direction, the multiple second light-emitting elements 30b may be mounted on the substrate 15 in a grid arrangement where the center of one second light-emitting element 30b is located at the position of each vertex of a square when multiple squares of the same side length are laid out without gaps. With this configuration, the multiple second light-emitting elements 30b can be arranged in an orderly manner, local brightness unevenness of the light emitted from the low-density arrangement area of ​​the light-emitting elements can be suppressed, and it is easy to emit light with uniform brightness from the low-density arrangement area of ​​the light-emitting elements.

[0045] The light-transmitting section is arranged on the light-emitting side of the multiple light-emitting elements 30 and includes multiple lenses 55 that correspond one-to-one with the multiple light-emitting elements 30, and the distance between the light-emitting elements 30 may be greater than or equal to the diameter of the lenses 55. Figure 15 is a plan view showing the arrangement structure of multiple lenses 255 in a lighting fixture of the second reference example. As shown in Figure 15, in multiple lenses 255 provided on a light-transmitting resin sheet 235, if the distance between adjacent lenses is shorter than the diameter of the lenses 255, the lenses 255 interfere with each other, and the lenses 255 do not form an independent, neat circular shape in a plan view when viewed from below in the height direction, and the light extraction efficiency decreases.

[0046] In contrast, as shown in the lighting fixture 1 of this embodiment in Figure 16, when the distance between the light-emitting elements 30 is greater than or equal to the diameter of the lens 55, the lenses 55 do not interfere with each other. Therefore, the light extraction efficiency can be increased, light loss can be reduced, and the emitted light can be made brighter. In addition, brightness unevenness can be reduced, and beautiful light can be emitted.

[0047] Multiple power supply components 5 may be mounted inside the multiple light-emitting elements 30 on the lower surface 15c of the substrate 15. If the power supply components 5, which emit a large amount of heat, are placed in the center of the substrate 15, and the multiple light-emitting elements 30 are arranged to surround the multiple power supply components 5, the high-temperature area will be surrounded by the multiple light-emitting elements 30, so heat tends to accumulate in the center of the substrate 15. Therefore, the effect of suppressing thermal degradation of components by providing a low-density arrangement area for light-emitting elements becomes significant.

[0048] When multiple power supply components 5 are mounted inside the multiple light-emitting elements 30 on the lower surface 15c of the substrate 15, the substrate 15 may have a substantially rectangular outer edge 15a when viewed from the height direction, and all or some of the multiple first light-emitting elements 30a may be arranged at both ends in the width direction of the substrate 15 at the center of the longitudinal direction of the substrate 15.

[0049] When the substrate 15 has a roughly rectangular outer edge 15a, if multiple power supply components 5 are placed in the center of the substrate 15, as shown in Figure 6, the light-emitting element placement area in the longitudinal center of the substrate 15 becomes smaller than the light-emitting element placement area at the longitudinal edges of the substrate 15. Therefore, the brightness of the light emitted from the longitudinal center of the substrate 15 in the width direction of the substrate tends to be lower than the brightness of the light emitted from the longitudinal edges of the substrate 15 in the width direction of the substrate. With the above configuration, since high-density light-emitting element placement areas are provided at both ends in the width direction of the substrate 15 in the longitudinal center of the substrate 15, the brightness of the light emitted from the longitudinal center of the substrate 15 in the width direction of the substrate can be increased.

[0050] This disclosure is not limited to the embodiments and their modifications, and various improvements and modifications are possible within the scope of the claims of this application and their equivalents. For example, the shortest distance between the plurality of first light-emitting elements and the plurality of power supply units may be longer than the shortest distance between the plurality of second light-emitting elements and the plurality of power supply components. This configuration makes it possible to significantly enhance the effects of the lighting fixture of this disclosure, such as the ease with which bright illumination light is emitted and the reduced likelihood of thermal degradation of components.

[0051] Furthermore, when multiple power supply components are mounted inside the multiple light-emitting elements (including multiple first light-emitting elements and multiple second light-emitting elements) on one side of the substrate, the multiple first light-emitting elements may be arranged on one side so as to surround the through-hole of the device body, and the multiple second light-emitting elements may be arranged on one side so as to surround the through-hole and be located inside the first light-emitting elements.

[0052] According to this configuration, a low-density arrangement area for light-emitting elements is provided around the outer periphery of multiple power supply components 5 that emit a large amount of heat, and a high-density arrangement area for light-emitting elements is provided around the outer periphery of the low-density arrangement area. Therefore, heat emitted from the center of the substrate is more easily dissipated outwards. In addition, since the high-density arrangement area for light-emitting elements is provided over a long and wide area on the outer periphery of the substrate, it is easier to increase the brightness of the illumination light. Thus, the effects of the illumination fixture of this disclosure, such as the ease of emitting bright illumination light and the reduced likelihood of thermal degradation of components, can be made particularly pronounced.

[0053] The case described above is where the high-density region of light-emitting elements is a honeycomb arrangement region of light-emitting elements, and the low-density region of light-emitting elements is a grid arrangement region of light-emitting elements. However, both the high-density and low-density regions of light-emitting elements may be honeycomb arrangement regions of light-emitting elements, and the distance between two adjacent light-emitting elements in the high-density region may be shorter than the distance between two adjacent light-emitting elements in the low-density region.

[0054] Alternatively, both the high-density and low-density regions of the light-emitting elements may be grid arrangement regions of the light-emitting elements, and the length of the grid sides in the high-density region may be shorter than the length of the grid sides in the low-density region. Alternatively, multiple light-emitting elements may have three or more different light-emitting element arrangement density regions. Alternatively, multiple light-emitting elements may have, in addition to the high-density and low-density regions, light-emitting element arrangement regions in which multiple light-emitting elements are randomly arranged and a uniform light-emitting element density cannot be defined. In short, the luminaire of this disclosure only needs to include multiple first light-emitting elements and multiple second light-emitting elements arranged at a lower density than the multiple light-emitting elements.

[0055] The case in which the resin sheet 35 constituting the light-transmitting portion includes a lens 55 corresponding to each light-emitting element 30 has been described, and the case in which there is a one-to-one correspondence between the light-emitting element 30 and the lens 55 has been described. Here, the multiple lenses 55 may have two or more different lenses. Also, the resin sheet constituting the light-transmitting portion may have fewer lenses than the number of light-emitting elements, and there may be light-emitting elements for which there is no corresponding lens. Alternatively, the resin sheet constituting the light-transmitting portion may not have any lenses.

[0056] The power supply cover 45, which covers multiple power supply components 5 mounted around the through-holes 11 of the circuit board 15, is composed of a first protective cover 60 and a second protective cover 70. However, the power supply cover that covers multiple power supply devices mounted around the through-holes of the circuit board may consist of only one protective cover made of resin or metal, or it may consist of three or more protective covers, each of which may be made of resin or metal.

[0057] The case in which the outer surface of the light-emitting side of the first protective cover 60 is made of white resin has been described. However, the outer surface of the light-emitting side of the first protective cover may have a metal layer, such as an aluminum layer, formed on a substrate made of metal or resin by vapor deposition, plating, sputtering, etc., in order to increase the reflectivity of light, and may also be mirror-finished by polishing, etc. Furthermore, a white coating film containing a white pigment may be formed on the outer surface of the light-emitting side of the first protective cover.

[0058] Alternatively, the first protective cover may be made of a metal such as silver, aluminum, or stainless steel, and a part of that metal may be mirror-finished. Alternatively, the first protective cover may be formed by fixing a mirror-finished aluminum material to a base material made of metal or resin. Alternatively, the outer surface of the power supply cover does not have to have a white portion; for example, the entire power supply cover may be made of transparent resin.

[0059] The third light-emitting element 16 constituting the night light was mounted inside the multiple light-emitting elements 30 and mounted in the mounting area of ​​the multiple power supply components 5. However, the third light-emitting element constituting the night light may be mounted outside the mounting area of ​​the multiple power supply components, or it may be placed outside the power supply cover. It is not necessary to arrange the multiple light-emitting elements on the outside of the multiple power supply components so as to surround them. For example, the multiple light-emitting elements may be placed only at both ends in the direction of extension of a pair of sides of a roughly rectangular substrate, and the multiple power supply components may be placed in the center in the direction of extension of the pair of sides.

[0060] Furthermore, the lighting fixtures of this disclosure may have the following configurations. Configuration 1: A lighting fixture comprising: a fixture body having a through hole in the center; a substrate arranged around the through hole of the fixture body; a plurality of light-emitting elements mounted on one side of the substrate so as to surround the through hole; and a light-emitting section covering the light-emitting side of the plurality of light-emitting elements, wherein the plurality of light-emitting elements include a plurality of first light-emitting elements and a plurality of second light-emitting elements arranged at a lower density than the plurality of first light-emitting elements. Configuration 2: The lighting fixture according to Configuration 1, wherein, in a plan view when viewed from the height direction, the plurality of first light-emitting elements are mounted on the substrate in a honeycomb arrangement such that when a plurality of equilateral triangles with the same side length are laid out without gaps, the center of one of the first light-emitting elements is located at the position of each vertex of the equilateral triangle. Configuration 3: In a plan view when viewed from the height direction, the plurality of second light-emitting elements are mounted on the substrate in a grid arrangement such that when a plurality of squares with the same side length are laid out without gaps, the center of one of the second light-emitting elements is located at the position of each vertex of the square, as in the lighting fixture according to Configuration 1 or 2. Configuration 4: The light-transmitting portion is arranged on the light-emitting side of the plurality of light-emitting elements and includes a plurality of lenses corresponding one-to-one to the plurality of light-emitting elements, wherein the distance between the light-emitting elements is greater than or equal to the diameter of the lenses, as described in any one of Configurations 1 to 3. Configuration 5: A lighting fixture according to any one of Configurations 1 to 4, wherein multiple power supply components are mounted inside the multiple light-emitting elements on one side. Configuration 6: A lighting fixture according to any one of Configurations 1 to 5, wherein the shortest distance between the plurality of first light-emitting elements and the plurality of power supply units is longer than the shortest distance between the plurality of second light-emitting elements and the plurality of power supply components. Configuration 7: The lighting fixture according to Configuration 5, wherein the plurality of first light-emitting elements are arranged on one side so as to surround the through-hole, and the plurality of second light-emitting elements are arranged on the one side so as to surround the through-hole and be located inside the first light-emitting elements. Configuration 8: The lighting fixture according to Configuration 5, wherein the substrate has a substantially rectangular outer edge when viewed from the height direction, and all or some of the plurality of first light-emitting elements are arranged at both ends in the width direction of the substrate in the longitudinal center of the substrate. [Explanation of symbols]

[0061] 1 Lighting fixture, 5 Power supply components, 10 Fixture body, 10a Bottom surface of fixture body, 11 Through hole of fixture body, 15 Substrate, 15a Outer edge of substrate, 15b Through hole of substrate, 15c Bottom surface of substrate, 16 Third light-emitting element, Chamber 18, 20 Light-emitting part, 25 Reflective sheet, 25a Cylindrical hole of reflective sheet, 25b Notch of reflective sheet, 30 Light-emitting element, 30a First light-emitting element, 30b Second light-emitting element, 35 Resin sheet, 35a Cylindrical hole of resin sheet, 35b Notch of resin sheet, 40 Receiving bracket, 41 Recess of receiving bracket, 45 Power supply cover, 50 Diffuser cover, 55 Lens, 60 First protective cover, 61 First through hole of first protective cover, 62 Second through hole of first protective cover, 63 64 Annular wall portion, 64 Fixing piece, 64a Screw hole of fixing piece, 64b Through hole of fixing piece, 64c Mounting base, 65 First projection of first protective cover, 65a Through hole of first projection, 67 Outer edge of first protective cover, 68 Second projection of first protective cover, 69 Recess, 70 Second protective cover, 70a Groove portion of second protective cover, 70b Projection portion of second protective cover, 70c Side surface of second protective cover, 70d Movement restricting portion of second protective cover, 70e Plate portion of second protective cover, 70f Screw hole of second protective cover, 71 Lens of second protective cover, 81 Power line, 85 Movement restricting member, 85a Receiving recess of movement restricting member, 85b Locking portion of movement restricting member, 85c Locking claw of movement restricting member.

Claims

1. The device body has a through hole in the center, A substrate arranged around the through hole of the main body of the device, Multiple light-emitting elements are mounted on one side surface of the substrate so as to surround the through-hole, The system comprises a light-emitting section that covers the light-emitting side of the plurality of light-emitting elements, The plurality of light-emitting elements include a plurality of first light-emitting elements and a plurality of second light-emitting elements arranged at a lower density than the plurality of light-emitting elements, in a lighting fixture.

2. The lighting fixture according to claim 1, wherein, in a plan view when viewed from the height direction, the plurality of first light-emitting elements are mounted on the substrate in a honeycomb arrangement such that when a plurality of equilateral triangles with the same side length are laid out without gaps, the center of one of the first light-emitting elements is located at the position of each vertex of the equilateral triangle.

3. The lighting fixture according to claim 1 or 2, wherein, in a plan view when viewed from the height direction, the plurality of second light-emitting elements are mounted on the substrate in a grid arrangement such that when a plurality of squares with the same side length are laid out without gaps, the center of one of the second light-emitting elements is located at the position of each vertex of the square.

4. The light-transmitting portion is arranged on the light-emitting side of the plurality of light-emitting elements and includes a plurality of lenses that correspond one-to-one with the plurality of light-emitting elements. The lighting fixture according to claim 1 or 2, wherein the distance between the light-emitting elements is greater than or equal to the diameter of the lens.

5. The lighting fixture according to claim 1 or 2, wherein a plurality of power supply components are mounted inside the plurality of light-emitting elements on the one side.

6. The lighting fixture according to claim 1 or 2, wherein the shortest distance between the plurality of first light-emitting elements and the plurality of power supply devices is longer than the shortest distance between the plurality of second light-emitting elements and the plurality of power supply components.

7. The plurality of first light-emitting elements are arranged on one side so as to surround the through hole. The lighting fixture according to claim 5, wherein the plurality of second light-emitting elements are arranged on one side surface so as to surround the through hole and be located inside the first light-emitting element.

8. The substrate has a roughly rectangular outer edge when viewed from the height direction, The lighting fixture according to claim 5, wherein all or some of the plurality of first light-emitting elements are arranged at both ends in the width direction of the substrate in the longitudinal center of the substrate.

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