JP7113366B2 - lighting equipment - Google Patents

Description

The present disclosure relates to lighting devices, and more particularly to in-ceiling lighting devices.

As a ceiling-embedded lighting device, a so-called downlight is widely known that includes a light-emitting module, a device main body that accommodates the module, and a cylindrical frame that is fixed to the device main body (for example, , see Patent Document 1). In the illumination device disclosed in the patent document, a lens is installed as a light distribution control member for controlling light emitted from the light emitting module. The lens is arranged in a state of protruding into the frame from the upper opening of the frame.

JP 2017-162695 A

Reducing unpleasant glare entering the field of view is an important issue in a ceiling-mounted lighting device. As disclosed in Patent Document 1, it is possible to reduce glare to some extent by controlling light distribution using a lens, but further improvement is required.

A lighting device according to one aspect of the present disclosure is a ceiling-embedded lighting device comprising a light emitting module, a first light distribution control member controlling light emitted from the light emitting module, and the first light distribution a second light distribution control member for controlling light emitted from the control member; the second light distribution control member includes a first opening formed on the first light distribution control member side and a bottom end side of the device; and a second opening larger than the first opening, and the opening area of the first opening of the expanding part is equal to that of the light exit surface of the first light distribution control member. It is characterized by being smaller than the area.

According to one aspect of the present disclosure, it is possible to reduce unpleasant glare entering the field of vision in a ceiling-embedded lighting device.

BRIEF DESCRIPTION OF THE DRAWINGS It is the perspective view which looked at the illuminating device which is an example of embodiment from the downward direction. 1 is an exploded perspective view of a lighting device that is an example of an embodiment, viewed from above; FIG. 1 is a cross-sectional view of a lighting device that is an example of an embodiment; FIG. It is a figure which shows the optical path of the illuminating device which is an example of embodiment. 4 is a perspective view showing a holder and a first light distribution control member as an example of an embodiment; FIG. FIG. 4 is a cross-sectional view of a second light distribution control member that is an example of an embodiment; It is a figure which shows the modification of a 2nd light distribution control member. It is a figure which shows an example of the suitable distance of the light-projection surface of a 1st light distribution control member, and the 1st opening of an expansion part. FIG. 11 is an exploded perspective view of a lighting device as another example of the embodiment, viewed from above; FIG. 4 is a cross-sectional view of a lighting device that is another example of an embodiment;

As described above, it is an important issue to reduce unpleasant glare entering the field of view in ceiling-mounted lighting devices. There is also known a method of suppressing glare by increasing the height of the reflecting surface of the frame to a predetermined value or more and narrowing the area where the light source can be viewed directly. However, although this method can suppress the glare of the light source, it is difficult to suppress the glare due to the reflecting surface of the frame. There is also a known method in which the reflecting surface of the frame is a mirror surface so that the light from the light source is mirror-reflected directly below so that the light source is not reflected when the frame is viewed from an angle (for example, , JP 2010-108859 A). However, this method requires the frame to have a mirror surface, and cannot be applied to a highly diffusive reflective surface such as a white surface.

Hereinafter, an example of an embodiment of a lighting device according to the present disclosure will be described in detail with reference to the drawings.

The lighting device according to the present disclosure is mounted on a horizontal ceiling in, for example, public facilities such as libraries and stations, commercial facilities such as department stores, shops, offices, residences, factories, and the like, and passageways. It can also be installed on a ceiling that is slanted against the The ceiling to which the lighting device is attached may be a part that partitions the upper part of the architectural space, and may be the ceiling of an entrance porch, a terrace, or the like.

FIG. 1 is a bottom perspective view of a lighting device 10 that is an example of an embodiment. FIG. 2 is an exploded perspective view of the illumination device 10 viewed from above. FIG. 3 is a vertical cross-sectional view of the illumination device 10, and FIG. 4 is a diagram showing the optical path of the illumination device 10 in FIG.

As illustrated in FIGS. 1 to 3, the illumination device 10 includes a light emitting module 20, a lens 40 (first light distribution control member) for controlling light emitted from the light emitting module 20, and light emitted from the lens 40. and a frame 50 (second light distribution control member) that controls the The frame body 50 is a cylindrical body with both axial ends opened, and has a first opening 61 formed on the lens 40 side and a second opening 62 formed on the lower end side of the device and larger than the first opening 61. and a cylindrical enlarged portion including

The shape of the first opening 61 and the second opening 62 is not particularly limited, and may be, for example, an elliptical shape, a perfect circular shape, or a rectangular shape. . The frame 50 has, as an enlarged portion, a tubular enlarged diameter portion 60 whose inner diameter (inner peripheral length) is enlarged toward the lower end of the device.

The illumination device 10 is a ceiling-embedded illumination device that is inserted into a ceiling hole with the second opening 62 of the frame 50 facing vertically downward, and is generally called a downlight. In this specification, for convenience of explanation, the vertically upward side of the lighting device 10 is referred to as "top" and the vertically downward side thereof is referred to as "bottom" when the lighting device 10 is mounted on a horizontal ceiling. In the following, the lens 40 is exemplified as the first light distribution control member, and the frame 50 and the second light distribution control member 70 are exemplified as the second light distribution control member, but the light distribution control members are not limited to these.

Although details will be described later, the opening area of the first opening 61 of the enlarged diameter portion 60 is smaller than the area of the light exit surface 41 of the lens 40 . In this embodiment, since the first opening 61 and the light exit surface 41 are substantially circular, it can be said that the diameter of the first opening 61 is smaller than the diameter of the light exit surface 41 . It is said that the human visual field is about 30 degrees vertically with respect to the horizontal direction. By making the diameter of the first opening 61, which is a light outlet located at a distance from the light exit surface 41, smaller than the diameter of the light exit surface 41, the spread of light is suppressed and unpleasant glare entering the field of vision is suppressed. can be reduced.

The illumination device 10 includes a device main body 11 that houses the light emitting module 20 . In the illumination device 10 , the lens 40 is housed inside the device main body 11 . A holder 30 that supports the light-emitting module 20 is provided inside the device main body 11 . The device main body 11 in which the light emitting module 20 , the holder 30 and the lens 40 are arranged is fixed to the top of the frame 50 . Note that the lens 40 may be fixed to the holder 30 .

The illumination device 10 has a structure in which a device main body 11 is provided in the upper portion and a frame body 50 is provided in the lower portion, and a holder 30 and a lens 40 are arranged in order from the top inside the device main body 11 . As illustrated in FIG. 4, light emitted from the light emitting module 20 passes through the lens 40, which is the first light distribution control member, and is introduced into the frame 50, which is the second light distribution control member. Light emitted from the light exit surface 41 of the lens 40 passes through a reduced diameter portion 56 (described later) formed in the frame 50 and is introduced from the first opening 61 into the enlarged diameter portion 60 . Then, the light is emitted from the second opening 62 of the expanded diameter portion 60 to the outside of the apparatus, that is, into the room.

The light-emitting module 20 housed in the device main body 11 has, for example, a structure in which a plurality of light sources are mounted on a substrate. The light source is preferably a semiconductor light-emitting element, and among these, an LED (Light Emitting Diode) is particularly preferable. The light emitting element may be sealed with a sealing layer containing a phosphor. In this case, the light source emits white light by converting part of the light from the light-emitting element into light with a longer wavelength using the phosphor. A circuit board on which metal wiring is formed can be applied to the substrate. The light-emitting module 20 releases heat to the device main body 11 via the heat radiation sheet 21 . The heat dissipation sheet 21 is a sheet made of, for example, silicone resin. Instead of the heat-dissipating sheet 21, or together with the heat-dissipating sheet, heat-dissipating grease may be used.

The apparatus main body 11 has a bottomed cylindrical base 12 and a plurality of radiation fins 13 and 14 erected on a top plate portion 12A of the base 12 . Each radiation fin 13 is radially formed around the center of the top plate portion 12A. Each radiation fin 14 extends radially from the tubular wall portion 12B of the base 12, and is formed so that a portion thereof overlaps the top plate portion 12A. Each radiation fin 14 is arranged substantially parallel to each other. The shape and the like of the heat radiation fins are not particularly limited, and the main body of the apparatus may not have heat radiation fins.

A plurality of through holes 16 through which screws 18 are inserted are formed in the top plate portion 12A of the base 12 . The holder 30 has a fastening portion 34 for the screw 18 . The holder 30 is fixed to the inner surface of the top plate portion 12A by screws 18 that are inserted into the base 12 through the through holes 16 . An opening (not shown) through which a lead wire connected to the light emitting module 20 is passed is formed in the top plate portion 12A. The illumination device 10 may include a sealing member 23 that closes the gap between the lead wire and the opening.

An annular flange portion 15 projecting radially outward is formed on the peripheral edge of the lower end opening of the base 12 . A plurality of through holes 17 through which screws 19 are inserted are formed in the flange portion 15 . The frame body 50 has fastening portions 55 for the screws 19 and is fixed to the lower portion of the device main body 11 using the screws 19 . In other words, the device main body 11 is screwed to the top of the frame 50 so as to close the top opening of the frame 50 .

The device main body 11 is manufactured by pressing, spinning, or die-casting a metal material mainly composed of aluminum, iron, or the like (the same applies to the frame body 50). However, the device main body 11 may be made of a resin material. The device main body 11 of this embodiment can be manufactured by die casting. The cylindrical wall portion 12B of the device main body 11 has a substantially cylindrical shape, but the shape of the cylindrical wall portion is not limited to this, and may be a cylindrical body having a rectangular cross section perpendicular to the axial direction.

5 and 6 in addition to FIGS. 1 to 4, the holder 30, the lens 40 which is the first light distribution control member, and the frame body 50 (particularly , diameter reduction portion 56 and diameter expansion portion 60) will be described in detail. 5 is a perspective view of the holder 30 and the lens 40, and FIG. 6 is a sectional view of the frame 50. FIG.

The holder 30 is a cylindrical body with a bottom and has a holding portion 31 that supports the light emitting module 20 . A window hole 32 for passing light emitted from the light emitting module 20 is formed in the center of the bottom of the holder 30 . The holding portion 31 is formed on the periphery of the window hole 32 and engages the light emitting module 20 . That is, the holder 30 has a substantially annular bottom portion in which a window hole 32 is formed in the center, and a substantially cylindrical side wall portion which is erected on the peripheral edge portion of the bottom portion. A fastening portion 34 to which the screw 18 is fastened is erected on the bottom of the holder 30 .

In the holder 30, the light emitting module 20 is supported with the surface on which the light source is mounted facing the window hole 32 side. The light-emitting module 20 abuts, for example, the inner surface of the top plate portion 12A of the device main body 11 and is sandwiched between the top plate portion 12A and the bottom portion of the holder 30 . A lens 40 is arranged below the holder 30 , and the light from the light emitting module 20 emitted downward through the window hole 32 is introduced into the lens 40 and light distribution is controlled by the lens 40 .

As illustrated in FIGS. 3 and 5, the holder 30 has a recess 33 into which the lens 40 is inserted. In this embodiment, the bottom portion of the holder 30 is inclined from the side wall portion toward the window hole 32 in the center so as to gradually approach the top plate portion 12A of the apparatus main body 11, and the concave portion 33 is formed on the outer surface of the bottom portion of the holder 30. It is In the illumination device 10, the upper portion of the lens 40 is inserted into the recess 33 of the holder 30, and at least a portion of the outer peripheral surface 42 of the lens 40 is covered with the inner surface of the recess 33 (bottom outer surface of the holder 30). The outer peripheral surface 42 may be in contact with the inner surface of the recess 33 .

The illumination device 10 preferably includes a light reflecting portion that covers the outer peripheral surface 42 of the lens 40 and reflects light leaking from the outer peripheral surface 42 into the lens 40 . A member that covers the outer peripheral surface 42 may be separately provided as the light reflecting portion, but in this embodiment, the inner surface of the concave portion 33 functions as the light reflecting portion. In this case, the inner surface of the concave portion 33 may be coated with a coating film containing a highly reflective filler (for example, a white pigment such as titanium oxide) in order to increase the light reflectance. Moreover, a metal layer, an inorganic compound layer, or the like having a high reflectance may be formed on the inner surface of the concave portion 33 by vapor deposition, plating, sputtering, or the like.

The lens 40 functions as a first light distribution control member that controls the light emitted from the light emitting module 20, as described above. The lens 40 is made of, for example, highly transparent resin such as acrylic resin (PMMA) or polycarbonate (PC), or glass. A radial cross section of the lens 40 and the light exit surface 41 are substantially circular. The lens 40 has a shape whose diameter gradually increases from the light incident side end (upper end) toward the light emitting side end (lower end). An outer peripheral surface 42 of the lens 40 is inclined so as to be located radially outward toward the lower end.

The outer peripheral surface 42 of the lens 40 is a total reflection surface configured to totally reflect the light from the light emitting module 20, for example. However, it is difficult to reflect all the light from the light-emitting module 20 , and part of the light leaks out of the lens 40 . In this embodiment, the outer peripheral surface 42 is covered with the inner surface of the concave portion 33 of the holder 30 , so the light emitted from the outer peripheral surface 42 is reflected by the inner surface of the concave portion 33 and returns into the lens 40 . In this way, by allowing the inner surface of the recess 33 to function as a light reflecting portion, it is possible to increase the light utilization efficiency.

The lens 40 has a concave portion 43 formed from the upper end to the central portion in the vertical direction. The bottom surface of the concave portion 43 has an upwardly convex curved shape, and the light emitting surface 41 has a downwardly convex curved surface 41a in a range overlapping the curved bottom surface of the concave portion 43 in the vertical direction. As illustrated in FIG. 4, most of the light emitted from the light emitting module 20 is introduced into the concave portion 43, and part of the light passes through the curved surface 41a of the light emitting surface 41 and is emitted from the curved surface 41a. Another part of the light introduced into the recess 43 is reflected by the outer peripheral surface 42 which is a total reflection surface, or reflected by the inner surface of the recess 33, and is reflected on the area of the light exit surface 41 other than the curved surface 41a (flat surface ).

The lens 40 may be fixed to the holder 30, but is supported by the frame 50 in this embodiment. Lens 40 has an overhang 44 formed at its lower end. The protruding portion 44 is an annular portion that protrudes radially outward and is used for fixing the lens 40 . The protruding portion 44 is placed on the tubular wall portion 51 of the frame 50 and sandwiched between the apparatus main body 11 and the frame 50 from above and below while the apparatus main body 11 is screwed to the frame 50 .

A packing 46 that closes the gap between the device main body 11 and the projecting portion 44 may be attached to the periphery of the projecting portion 44 . By providing the packing 46 , for example, the lens 40 can be stably fixed, and insects, dust, etc. can be prevented from entering the device main body 11 . Also, by providing the packing 46, it is possible to take measures against abnormal noise caused by the difference in thermal expansion between the lens 40 and the device body 11 or the frame 50. FIG.

Here, the light exit surface 41 of the lens 40 includes a surface from which light that enters the recess 43 and is controlled by the bottom surface of the recess 43 and the curved surface 41a exits, a side surface of the recess 43 and the outer peripheral surface 42 or the recess. The inner surface of 33 and the surface from which controlled light is emitted. Although a small amount of light is emitted from the lower surface of the projecting portion 44 , the lower surface of the projecting portion 44 is not included in the light emitting surface 41 because it is not the surface from which the above-described controlled light is emitted.

The frame 50 functions as a second light distribution control member that controls the light emitted from the lens 40 as described above. The frame 50 has a substantially cylindrical shape with both upper and lower ends opened. However, the inner diameter of the frame body 50 is not constant, and an enlarged diameter portion 60 is formed in the lower part of the frame body 50 so that the inner diameter increases toward the lower end side. A second opening 62 is formed at the lower end of the frame 50 (enlarged diameter portion 60), and the light introduced into the frame 50 through the upper end opening is emitted to the outside of the device through the second opening 62, which is the lower end opening. be done.

Further, in the upper portion of the frame body 50, there is a cylindrical reduced portion whose inner peripheral length is reduced toward the first opening 61 side. In this embodiment, as the reduced portion, a substantially cylindrical reduced diameter portion 56 whose diameter gradually decreases from the upper end opening of the frame 50 toward the first opening 61 is provided. Light emitted from the lens 40 is introduced into the enlarged diameter portion 60 through the cylinder of the reduced diameter portion 56 .

A mounting spring 52 for mounting the lighting device 10 on the ceiling may be fixed to the frame 50 . The mounting spring 52 has a leaf spring structure and extends horizontally. The lighting device 10 is fixed to the ceiling by abutting the mounting spring 52 around the embedded hole in the ceiling in the space above the ceiling. In this embodiment, the mounting spring 52 is fixed to a spring fixing portion 53 formed on the outer surface of the tubular wall portion 51 of the frame 50 . The spring fixing portion 53 has a structure into which one end portion of the mounting spring 52 can be inserted, and two spring fixing portions 53 are formed side by side in the radial direction of the frame 50 . The number of mounting springs 52 and spring fixing portions 53 is not particularly limited, and may be three, for example.

The frame 50 has a tubular wall portion 51 and a flange portion 54 formed at the lower end portion of the tubular wall portion 51 . The illumination device 10 is attached to the ceiling with the device main body 11 and the upper portion of the frame 50 inserted into the space above the ceiling through the embedded hole, and the flange portion 54 substantially abutting the peripheral edge of the embedded hole in the ceiling surface. In this embodiment, a groove formed in the tubular wall portion 51 divides the upper portion of the tubular wall portion 51 into an outer wall 51A and an inner wall 51B. The flange portion 15 of the apparatus body 11 is placed on the outer wall 51A, and the lens 40 is placed on the inner wall 51B.

The outer wall 51A is provided with a plurality of fastening portions 55 to which the screws 19 for fixing the device main body 11 are fastened. The screw 19 is inserted into the through hole 17 of the flange portion 15 placed on the outer wall 51A and fastened to the fastening portion 55 . As a result, the device main body 11 is screwed to the frame 50 .

The frame 50 has a reduced diameter portion 56 at its upper portion and an enlarged diameter portion 60 at its lower portion. The first opening 61 of the expanded diameter portion 60 is formed, for example, in the vertical central portion of the frame 50 . In this case, the vertical lengths of the diameter-reduced portion 56 and the diameter-enlarged portion 60 are substantially the same. Details of a suitable distance between the light exit surface 41 of the lens 40 and the first opening 61 will be described later.

The reduced-diameter portion 56 is a tapered portion having an inner diameter that decreases toward the first opening 61 , and is provided between the lens 40 and the enlarged-diameter portion 60 . The cross section of the reduced diameter portion 56 has a substantially perfect circular shape. The reduced diameter portion 56 is a space surrounded by the inner wall 51B, and is formed by inclining the inner wall 51B so that the lower end portion of the inner wall 51B is located inside the upper end portion. Also, the inner surface of the reduced diameter portion 56 is preferably a light absorbing surface as described later. By providing the reduced-diameter portion 56, it becomes easy to suppress the spread of light and reduce unpleasant glare entering the field of view.

The inner diameter at the lower end of the reduced diameter portion 56 is, for example, 70% to 95% of the inner diameter at the upper end. The inner diameter at the upper end of the reduced diameter portion 56 may be smaller or larger than the diameter of the light exit surface 41 of the lens 40 . In this embodiment, the inner diameter of the upper end of the diameter-reduced portion 56 is substantially the same as the diameter of the light exit surface 41 or slightly larger than the diameter of the light exit surface 41 . The inner diameter at the lower end of the diameter-reduced portion 56 is preferably smaller than the diameter of the light exit surface 41 .

The inner surface of the reduced diameter portion 56 is preferably a black or other light absorbing surface that absorbs part of the light emitted from the lens 40 . If the inner surface of the diameter-reduced portion 56 is used as a light absorbing surface, the efficiency of light utilization is reduced, but the light that hits the inner surface of the diameter-reduced portion 56 can be absorbed and cut, so that the light emitted from the lens 40 can be further focused. and the glare reduction function is improved. The inner surface of the diameter-reduced portion 56 may be formed with a coating film containing a filler having a high light absorption rate (for example, a black pigment such as carbon black). Also, a metal layer, an inorganic compound layer, or the like that absorbs light may be formed by vapor deposition, plating, sputtering, or the like. Alternatively, the frame 50 may be made of a material with high light absorption.

On the other hand, like the inner surface of the concave portion 33 , the inner surface of the reduced-diameter portion 56 may be a light reflecting surface that reflects part of the light emitted from the lens 40 . If the inner surface of the reduced diameter portion 56 is used as a light reflecting surface, the glare reduction function is lowered, but the light utilization efficiency can be increased.

A translucent cover 57 is attached to the lower end portion of the diameter-reduced portion 56 so as to cover the lower end opening of the diameter-reduced portion 56 . The translucent cover 57 may be made of transparent resin or glass and have a lens function. The translucent cover 57 has a diameter larger than the diameter of the first opening 61 of the enlarged diameter portion 60 and is arranged at the boundary portion between the reduced diameter portion 56 and the enlarged diameter portion 60 . A packing 58 is attached to the periphery of the translucent cover 57 to close the gap between the inner surface of the reduced diameter portion 56 and the cover. By providing the packing 58 , for example, the translucent cover 57 can be stably fixed, and insects, dust, etc. can be prevented from entering the diameter-reduced portion 56 .

As described above, the diameter-enlarged portion 60 has a shape that widens toward the second opening 62 and has an inner diameter that widens. The enlarged diameter portion 60 has an inner diameter that gradually increases from the upper end toward the lower end. A radial cross section of the inner surface of the enlarged diameter portion 60 preferably has a substantially perfect circular shape. The inner diameter at the lower end of the expanded diameter portion 60, that is, the diameter of the second opening 62, is, for example, 150% to 250% of the inner diameter at the upper end, that is, the diameter of the first opening 61.

The first opening 61 is smaller than the diameter of the light exit surface 41 of the lens 40 as described above. The light exit surface 41, the first opening 61, and the second opening 62 are all preferably substantially circular. In FIG. 5, the area surrounded by the dotted line is the light exit surface 41, and the area surrounded by the dashed line, which is one size smaller than the light exit surface 41, is the area R61 corresponding to the size of the first opening ₆₁ . . The lens 40 is arranged such that the center of the light exit surface 41 and the center of the first opening 61 overlap vertically. A curved surface 41a is formed in the central portion of the lens 40, and it is preferable that the center of the curved surface 41a and the center of the first opening 61 overlap in the vertical direction.

The first opening 61 is formed in the vertical central portion of the frame 50 as described above. The first opening 61 may be formed on the lower end side of the vertical center of the frame 50 . By forming the first opening 61 at a position away from the upper end of the frame 50, the light exit surface 41 of the lens 40 can be kept away from the first opening 61, thereby improving the glare reduction function. The ratio of the vertical length of the expanded diameter portion 60 to the vertical length of the guide member 90 is, for example, 4:6 to 6:4, and may be substantially the same.

In the lighting device 10, the lens 40 preferably controls the light emitted from the light emitting module 20 to be focused within the device. It is particularly preferred that the lens 40 controls the light of the light emitting module 20 to be focused within the enlarged diameter portion 60 or at and near the first opening 61 of the enlarged diameter portion 60 . In this case, the glare reduction function can be enhanced while suppressing the temperature rise of the lighting device 10 . Such a focal position is, for example, the shape of the lens 40, the vertical length from the upper end of the frame 50 to the first opening 61 (distance h from the light exit surface 41 to the first opening 61), the vertical direction of the enlarged diameter portion 60 It can be controlled by adjusting the length or the like.

As illustrated in FIG. 6, the inner surface 63 of the enlarged diameter portion 60 is an inwardly convex curved surface. In this case, the angle θ1 between the tangential line β of the inner surface 63 of the enlarged diameter portion 60 and the central axis α of the enlarged diameter portion 60 must be larger than the angle corresponding to 1/2 of the 1/2 beam angle of the illumination device 10. is preferred. Among the angles θ1, the angle formed by the tangent β of the upper end of the inner surface 63 and the central axis α is the smallest, but this angle is also larger than the angle corresponding to 1/2 of the 1/2 beam angle. In this case, the inner surface 63 of the expanded diameter portion 60 is less likely to be exposed to light, and the glare reduction function is improved. The inner surface 63 of the enlarged diameter portion 60 may be curved, for example, so that the curvature becomes large at the center portion of the enlarged diameter portion 60 in the vertical direction.

FIG. 7 is a diagram showing a modification of the frame 50. As shown in FIG. As illustrated in FIG. 7, the inner surface 63x of the enlarged diameter portion 60x may be an outwardly convex curved surface. In this case, the angle θ2 between the virtual line γ connecting the edge of the first opening 61x and the edge of the second opening 62x and the central axis α of the expanded diameter portion 60x is 1/2 the beam angle of the illumination device 10. It is preferably larger than the angle corresponding to /2. By setting the angle θ2 within this range, as in the case of the expanded diameter portion 60, it becomes difficult for light to hit the inner surface 63x, and the glare reduction function is improved.

The 1/2 beam angle of the illumination device 10 can be measured by a light distribution measurement device. The half beam angle of illumination device 10 is, for example, between 10° and 60°, preferably about 40°. The 1/2 beam angle can be controlled by adjusting the curvature of the bottom surface and curved surface 41a of the concave portion 43 of the lens 40, the angle of the side surface of the concave portion 43 and the outer peripheral surface 42, the curvature of the concave portion 33 of the holder 30, and the like.

FIG. 8 is a diagram showing an example of a suitable distance h between the light exit surface 41 of the lens 40 and the first opening 61 of the enlarged diameter portion 60 when the inner surface 63 of the enlarged diameter portion 60 is an inwardly convex curved surface. is. The distance h preferably satisfies the following formula 1, where φ1 is the diameter (opening dimension) of the first opening 61 and φ2 is the diameter of the light exit surface 41 .
(Formula 1) h≧(φ2−φ1)/2×tanθ1
The distance h based on Equation 1 is preferably calculated using the smallest angle θ1.
Further, in the case of the enlarged diameter portion 60x, the distance h preferably satisfies the condition of the following formula 2, where φ1 is the diameter (opening dimension) of the first opening 61x and φ2 is the diameter of the light exit surface 41. .
(Formula 2) h≧(φ2−φ1)/2×tanθ2

As described above, according to the ceiling-embedded lighting device 10 having the above configuration, it is possible to suppress the spread of light and reduce unpleasant glare entering the field of view. In the illumination device 10 , the light emitted from the light emitting module 20 is subjected to light distribution control by the lens 40 and the frame 50 and emitted from the second opening 62 of the enlarged diameter portion 60 to the outside of the device. The light emitted from the light exit surface 41 of the lens 40 is further constricted by, for example, the reduced diameter portion 56 and is irradiated into the room or the like with a narrow beam angle without brightly illuminating the inner surface 63 of the enlarged diameter portion 60 . In particular, when the distance h between the light exit surface 41 (flat surface) of the lens 40 and the first opening 61 of the enlarged diameter portion 60 satisfies the above formula, the glare reduction function is further improved.

9 and 10 show a lighting device 100 as another example of the embodiment. 9 is an exploded perspective view of lighting device 100, and FIG. 10 is a sectional view of lighting device 100. As shown in FIG. In the following, the same reference numerals are used for the same components as in the above-described embodiment, and overlapping descriptions are omitted.

As illustrated in FIGS. 9 and 10 , in lighting device 100 , second light distribution control member 70 is composed of frame body 80 and guide member 90 . It is different from the illumination device 10 configured with The guide member 90 is arranged above the enlarged diameter portion 60 within the frame 80 . An upper space capable of accommodating the guide member 90 exists in the upper portion of the frame 80 . The guide member 90 is a cylindrical body with both axial ends open, and has a function of guiding the light emitted from the lens 40 to the first opening 61 of the enlarged diameter portion 60 . The guide member 90 may be made of a metal material or a resin material, like the device main body 11 and the frame 80, for example.

The guide member 90 has a cylindrical reduced-diameter portion 91 whose inner diameter is reduced toward the first opening 61 side of the enlarged-diameter portion 60 , and is provided between the lens 40 and the enlarged-diameter portion 60 . The reduced-diameter portion 91 has a substantially circular cross section and is formed in a tapered shape in which the inner diameter gradually decreases from the upper end toward the lower end. In the illumination device 100 , the second light distribution control member 70 is provided with the reduced diameter portion 91 by disposing the guide member 90 having the reduced diameter portion 91 above the frame 80 . As in the illumination device 10 , by providing the diameter-reduced portion 91 above the diameter-enlarged portion 60 , the light emitted from the lens 40 can be focused. As the shape of the diameter-reduced portion 91, the same shape as that of the diameter-reduced portion 56 described above can be applied.

The guide member 90 has a flange portion 92 formed at its upper end. The flange portion 92 is formed in an annular shape so as to protrude radially outward from the peripheral edge portion of the upper end opening of the guide member 90 . The flange portion 92 is arranged on the inner wall 81B of the frame 80 and supports the projecting portion 44 of the lens 40 . Further, the inner wall 81B of the frame 80 is provided with a plurality of positioning pin insertion portions 82 into which positioning pins (not shown) formed on the lower surface of the flange portion 92 are inserted. The device main body 11 is screwed to the outer wall 81A of the cylindrical wall portion 81 in the same manner as the lighting device 10 .

In the example shown in FIG. 10, a plurality of recesses 45 are formed on the surface (lower surface) of the projecting portion 44 facing the guide member 90 (flange portion 92). The recesses 45 are formed, for example, at substantially equal intervals on substantially the same circumference. The flange portion 92 has a plurality of projections 93 that protrude upward at a portion on which the projecting portion 44 is placed. A plurality of protrusions 93 are formed at the same intervals as the recesses 45 so as to fit into the recesses 45 of the projecting portion 44 . By providing the concave portion 45 and the projection 93, it is possible to prevent the lens 40 from deviating in the radial direction from the intended arrangement.

The inner surface of the reduced diameter portion 91 is preferably a light absorbing surface that absorbs part of the light emitted from the lens 40 . In this case, since the light striking the inner surface of the reduced-diameter portion 91 can be absorbed and cut, the light emitted from the lens 40 can be further narrowed, and the glare reduction function can be improved. On the inner surface of the reduced diameter portion 91, similarly to the case of the reduced diameter portion 56, a coating film containing a filler having a high light absorption rate may be formed. A metal layer, an inorganic compound layer, or the like may be formed. Alternatively, the guide member 90 may be made of a material having a high light absorption rate. A reflective surface may be formed on the inner surface of the reduced diameter portion 91 .

A translucent cover 57 is attached to the lower end of the guide member 90 so as to cover the lower end opening of the reduced diameter portion 91 . The translucent cover 57 may be made of transparent resin or glass and have a lens function. The translucent cover 57 has a diameter larger than the diameter of the first opening 61 of the enlarged diameter portion 60 and is arranged between the enlarged diameter portion 60 and the guide member 90 . A packing 58 is attached to the periphery of the translucent cover 57 to close the gap between the inner surface of the reduced diameter portion 56 and the cover. By providing the packing 58 , for example, the translucent cover 57 can be stably fixed, and insects, dust, etc. can be prevented from entering the diameter-reduced portion 56 .

10 lighting device, 11 device main body, 12 base, 12A top plate portion, 12B cylinder wall portion, 13, 14 heat radiation fins, 15, 54 flange portions, 16, 17 through holes, 18 screws, 20 light emitting module, 21 heat radiation sheet, 23 Sealing member 30 Holder 31 Holding part 32 Window hole 33 Recessed part 34, 55 Fastening part 40 Lens 41 Light exit surface 41a Curved surface 42 Peripheral surface 43 Recessed part 44 Overhang part 45 Recess 46, 58 Packing 50, 80 Frame 51, 81 Cylindrical wall 51A, 81A Outer wall 51B, 81B Inner wall 52 Mounting spring 53 Spring fixing part 56, 91 Reduced diameter part 57 Translucency Cover 60 Expanded diameter portion 61 First opening 62 Second opening 63 Inner surface 70 Second light distribution control member 82 Positioning pin insertion portion 90 Guide member 92 Flange portion 93 Projection

Claims (6)

A ceiling-embedded lighting device,
a light emitting module;
a first light distribution control member that controls light emitted from the light emitting module;
a second light distribution control member for controlling light emitted from the first light distribution control member;
with
The second light distribution control member has a tubular shape including a first opening formed on the side of the first light distribution control member and a second opening formed on the lower end side of the device and larger than the first opening. an enlarging portion , and a cylindrical contracting portion having an inner peripheral length that decreases toward the first opening between the first light distribution control member and the first opening of the enlarging portion ;
The opening area of the first opening of the enlarged portion is smaller than the area of the light exit surface of the first light distribution control member,
an inner surface of the reducing portion is a light absorbing surface that absorbs part of the light emitted from the first light distribution control member;
The illumination device, wherein the first light distribution control member is a lens. A ceiling-embedded lighting device,
a light emitting module;
a first light distribution control member that controls light emitted from the light emitting module;
a second light distribution control member for controlling light emitted from the first light distribution control member;
with
The second light distribution control member has a tubular shape including a first opening formed on the side of the first light distribution control member and a second opening formed on the lower end side of the device and larger than the first opening. having an enlarged portion,
The opening area of the first opening of the enlarged portion is smaller than the area of the light exit surface of the first light distribution control member,
The illumination device, wherein the first light distribution control member is a lens, and controls light emitted from the light emitting module so as to focus on the first opening of the enlargement section and its vicinity . A ceiling-embedded lighting device,
a light emitting module;
a first light distribution control member that controls light emitted from the light emitting module;
a second light distribution control member for controlling light emitted from the first light distribution control member;
a light reflecting part that covers the outer peripheral surface of the first light distribution control member and reflects light leaking from the outer peripheral surface into the first light distribution control member;
with
The second light distribution control member has a tubular shape including a first opening formed on the side of the first light distribution control member and a second opening formed on the lower end side of the device and larger than the first opening. having an enlarged portion,
The illumination device, wherein the opening area of the first opening of the enlarged portion is smaller than the area of the light exit surface of the first light distribution control member. further comprising a holder that supports the light emitting module;
4. The lighting device according to claim 3 , wherein said holder has a recess into which said first light distribution control member is inserted, and an inner surface of said recess functions as said light reflecting portion. An angle θ1 formed by a tangent to the inner surface of the enlarged portion and the central axis of the enlarged portion, or an imaginary line connecting the edge of the first opening and the edge of the second opening of the enlarged portion and the central axis The lighting device according to any one of claims 1 to 4 , wherein the formed angle θ2 is larger than an angle corresponding to 1/2 of the 1/2 beam angle of the device. The distance h between the light exit surface of the first light distribution control member and the first opening of the enlarged portion is given by: 6. The lighting device according to claim 5 , which satisfies the condition of Expression 1 or Expression 2 below.
(Formula 1) h≧(φ2−φ1)/2×tanθ1
(Formula 2) h≧(φ2−φ1)/2×tanθ2

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