WO2015060450A1

WO2015060450A1 - Illuminating instrument

Info

Publication number: WO2015060450A1
Application number: PCT/JP2014/078419
Authority: WO
Inventors: 曄道悟朗; 平井啓介
Original assignee: 株式会社モデュレックス
Priority date: 2013-10-27
Filing date: 2014-10-26
Publication date: 2015-04-30
Also published as: JPWO2015060450A1; JP5946972B2

Abstract

[Problem] To provide an illuminating instrument that can use a planar light source with a large light-emitting surface and can reflect the light from the light emitting surface as directional light even in such a case. [Solution] An illuminating instrument is provided with a planar light source (20) having a planar light emitting surface (20d) orthogonal to a center axis (C1) and a reflector (40) that reflects light from the light emitting surface (20d) at a reflecting surface with the center axis (C1) as a reference. The reflecting surface has a first reflecting surface (41) that has a parabolic surface shape formed by rotation centered on the center axis (C1) of one part of a first parabolic line (Pr1), which has the center axis (C1) as an axis of symmetry, and a second reflecting surface (42) that has a parabolic surface shape formed by rotation centered on the center axis (C1) of one part of a second parabolic line (Pr2), which has a center axis (C2) parallel to the center axis (C1) as an axis of symmetry.

Description

lighting equipment

The present invention relates to a lighting device having a planar light source and a reflector, such as a downlight, a spotlight, and the like.

¡In lighting fixtures such as downlights and spotlights, the light generated from the light source is controlled by reflecting it with a reflector.

The lighting fixture disclosed in Patent Document 1 includes an LED element, a reflector, and a housing. And the several level | step difference which has curved-surface recessed parts, such as a paraboloid, is arrange | positioned at the reflective surface of a reflector.

According to this luminaire, it is said that the reflection surface with a step can provide an appropriate spread in the reflection angle distribution of the reflected light and improve the illuminance uniformity on the irradiated surface. Furthermore, it is said that it is possible to irradiate a target object several hundred meters ahead with a uniform amount of light.

JP 2013-127944 A

However, according to the invention of Patent Document 1, the step of the reflecting surface is configured so that the reflection angle distribution of the reflected light has an appropriate spread, so that the amount of parallel light that is highly directional and parallel to the optical axis is high. Not suitable for increasing. Further, a light source having a planar light emitting surface is used as the light source, and the light emitting surface size is not increased so as to increase the light emission amount.

The present invention has been made in view of the above-described circumstances, and a planar light source having a large light emitting surface can be used. Even in this case, light from the light emitting surface can be effectively reflected as parallel light. It aims at providing a lighting fixture.

The invention according to claim 1 is a lighting apparatus, wherein a light source having a planar light emitting surface orthogonal to a central axis, a reflector that reflects light from the light emitting surface with a reflective surface based on the central axis, The reflecting surface includes a parabolic first reflecting surface formed by rotating a part of a first parabola about the central axis about the central axis, and the center. A parabolic second reflecting surface formed by rotating a part of a second parabola with an axis parallel to the axis as an axis of symmetry about the central axis. To do.

According to a second aspect of the present invention, in the lighting apparatus according to the first aspect, the first reflective surface and the second reflective surface are disposed on the side where the second reflective surface is close to the light source, The first reflecting surfaces are arranged on the side far from the light source and are continuous with each other.

The invention according to claim 3 is the luminaire according to

claim

1 or 2, characterized in that a focal length of the second parabola is shorter than a focal length of the first parabola.

According to a fourth aspect of the present invention, in the luminaire according to any one of the first to third aspects, the focal point of the first parabola and the focal point of the second parabola are set on the light emitting surface. It is characterized by that.

According to a fifth aspect of the present invention, in the lighting apparatus according to any one of the first to fourth aspects, the second reflecting surface has an opening surface facing the light emitting surface, and the opening surface is It is characterized by being larger than a virtual opening surface formed by intersecting a virtual extension portion obtained by extending the first reflecting surface to the light emitting surface side and the opening surface.

According to the present invention, the reflector has the first reflecting surface and the second reflecting surface whose reflecting surfaces are parabolic, and, for example, one reflecting surface whose reflecting surface is parabolic. It is possible to use a planar light source having a larger light emitting surface as compared with the case where it is configured by. Even in this case, the light from the light emitting surface can be effectively reflected by the first reflecting surface and the second reflecting surface to be parallel light.

It is the disassembled perspective view of the lighting fixture 1 seen from the upper end Ca side of the central axis C1. It is the disassembled perspective view of the lighting fixture 1 seen from the lower end Cb side of the central axis C1. (A) is a plan view (top view) for explaining the heat conduction of the luminaire 1, and (B) is a view taken along line III-III-III in FIG. FIG. 4 is a view taken along the arrow line III-III in FIG. 3A for explaining thermal radiation of the luminaire 1. FIG. 4 is a view taken along the arrow line III-III in FIG. 3A for explaining convective heat transfer of the lighting fixture 1. It is a figure explaining the planar light source 20 and the connector 21. FIG. It is a figure explaining the focus f and the focal distance y of a parabola. It is a figure explaining the open condition (size of a curve) of parabola Pr5, Pr10, Pr15, and Pr20 whose focal distance y is 5, 10, 15, and 20 mm. It is a figure explaining a mode that the opening part (light entrance) K in reflector Ra formed with the parabola matched with the external shape of the body 30 becomes small. It is a figure explaining a mode that height H of reflector Rb formed with a parabola with a big focal distance y becomes low (length becomes short). It is a figure explaining reflection of light in case reflector Rc is an ellipse other than a parabola. It is a figure explaining a mode that the reflective surface of the reflector 40 formed by combining the 1st reflective surface 41 and the 2nd reflective surface 42 which consist of two parabolas Pr1 and Pr2 from which the focal distance y differs. FIG. 4 is a view corresponding to a view taken along the line III-III-III in FIG. 3A, illustrating a state in which the planar light source 20 is replaced with a lamp 62 as a light source. It is a figure explaining the synthesis | combination of the 1st reflective surface 41 and the 2nd reflective surface. It is a figure explaining the magnitude relationship of the opening surface K2 and the light emission surface 20d.

Hereinafter, embodiments to which the present invention is applied will be described in detail with reference to the drawings. In addition, in each drawing, the member etc. which attached | subjected the same code | symbol are the things of the same or similar structure, The duplicate description about these shall be abbreviate | omitted suitably. Moreover, in each drawing, members and the like that are not necessary for the description are omitted as appropriate.
<Embodiment 1>
A lighting apparatus 1 according to Embodiment 1 to which the present invention is applied will be described with reference to FIGS.

Here, FIG. 1 is an exploded perspective view of the lighting fixture 1 as seen from the upper end Ca side of the central axis C1. FIG. 2 is an exploded perspective view of the lighting fixture 1 as seen from the lower end Cb side of the central axis C1. 3A is a plan view (top view) illustrating the heat conduction of the luminaire 1, and FIG. 3B is a view taken along the line III-III in FIG.
In the following description, for convenience of explanation, it is assumed that the upper and lower sides in FIGS. 1 to 3 correspond to the upper and lower sides of the lighting fixture 1, respectively.

As shown in FIGS. 1 to 3, the luminaire 1 includes a socket holder 10, a planar light source (LED module) 20, a body, and a body disposed substantially in order from the upper end Ca side to the lower end Cb side along the central axis C1. 30, a reflector 40, and a hood 50. Hereinafter, it demonstrates in this order.

The socket holder 10 connects a heat sink 11 disposed on the central axis C1, a plurality (a large number) of

radiation fins

12, 12,... Extending radially from the outer circumferential surface of the heat sink 11, and the outer circumferential ends of the

radiation fins

12, 12,. And an outer peripheral wall 13 having a substantially cylindrical shape. The heat sink 11, the radiation fins 12, 12,... And the outer peripheral wall 13 are integrally formed by, for example, aluminum die casting.

The heat sink 11 has a disc portion 11a, a conical portion 11b, and a leg portion 11c, which are integrally formed. The disc part 11a has a mounting surface 11d of the planar light source 20 which is flat on the lower surface. Moreover, as for the disc part 11a, the outer diameter of the outer peripheral surface 11e becomes small, so that it approaches the upper end side from a lower end side. The conical part 11b has an inclined surface 11g that gently descends from the top part 11f toward the outer periphery. The leg part 11c is formed in a substantially cylindrical shape, the upper end is continuous with the peripheral part of the mounting surface 111d, and the diameter of the outer peripheral surface 11h is increased toward the lower end part. The outer peripheral surface 11h of the leg portion 11c and the outer peripheral surface 11e of the disk portion 11a described above are linearly continuous. At the lower end of the outer peripheral surface 11h of the leg portion 11c, a flange portion 11i protrudes outward along the entire circumference.

The

heat radiating fins

12, 12,... Are formed so as to extend radially outward from the outer peripheral surface 11e of the disk portion 11a of the heat sink 11, the outer peripheral surface 11h of the leg portion 11c, and the inclined surface 11g of the conical portion 11b. Yes. Further, as shown in FIG. 3A, the

radiation fins

12, 12,... Are gently curved as viewed from above. Thereby, since a surface area can be enlarged and the flow of air can be made smooth, heat dissipation efficiency improves. The radiating

fins

12, 12... Have a lower end 12a extending to the vicinity of the flange portion 11i, and an upper end 12b extending outward to the upper end 13b of the outer peripheral wall 13 and inwardly inclined downward to intersect the inclined surface 11g of the conical portion 11b. is doing. Each radiating fin 12 is formed such that the upper end 12b side is thin and the lower end 12a side is thick.

The outer peripheral wall 13 is formed in a substantially cylindrical shape so as to connect the outer peripheral ends of the

radiation fins

12, 12. In the outer peripheral wall 13, the diameter (inner diameter) of the inner peripheral surface 13c increases as it approaches the upper end 13b side from the lower end 13a side, and the diameter (outer diameter) of the outer peripheral surface 13d is substantially constant from the lower end 13a side to the upper end 13b side. It has become. For this reason, the outer peripheral wall 13 is thicker toward the lower end 13a and thinner toward the upper end 13b.

In the socket holder 10 having the heat sink 11, the

radiation fins

12, 12... And the outer peripheral wall 13, an annular air inlet A <b> 1 is formed between the flange portion 11 i and the lower end 13 a of the outer peripheral wall 13. . The air inlet A1 is formed between an inclined surface 13e inside the lower end 13a of the outer peripheral wall 13 and an inclined surface 30b of an upper end 30a of the body 30 described later. In addition, the

inclined surfaces

13e and 30b are inclined in the same direction, and the air flowing from the outside to the inside between them is at the lower end of the outer peripheral surface 11h of the leg portion 11c of the heat sink 11 along the

inclined surfaces

13e and 30b. It is designed to flow toward you. In addition, an area (space) surrounded by two

adjacent radiation fins

12 and 12, outer

peripheral surfaces

11 e and 11 h and inclined surfaces 11 g of the heat sink 11, and an inner peripheral surface 13 c of the outer peripheral wall 13 is vertically Are the same number of air flow paths A2, A2,... As the

heat dissipating fins

12, 12,. These flow paths A2, A2,... Increase in the cross-sectional area in the horizontal direction as they go from the lower side to the upper side. That is, it gradually becomes wider as it goes upward. Each of the flow paths A2, A2,... Communicates with the above-described annular air intake A1.
The movement of heat generated by light emission of the planar light source 20, which will be described next, that is, heat conduction, convection heat transfer, and heat radiation will be described later in detail.
FIG. 6 is a view of the planar light source 20 and the connector 21 as viewed from below.

As the planar light source 20, for example, a so-called (chip on board) type LED module in which a large number of small LED elements are arranged in a planar shape can be used. For example, as shown in FIG. 1, FIG. 2, and FIG. 6, this has an anode (positive electrode) 20b and a cathode (negative electrode) 20c at two corners on a square aluminum substrate 20a, respectively. . A light emitting surface (light emitting area) 20d in which a large number (for example, 100 to 200) of LED elements are mounted in a circle is formed in the center, and the surface of the light emitting surface 20d is sealed with a silicone resin containing a phosphor. Configured. For example, light is emitted from each LED element with an irradiation angle of 120 °.

The planar light source 20 is fixed from below to the mounting surface 11d of the disk portion 11a of the heat sink 11 by, for example, a rectangular plate-shaped connector 21. As shown in FIG. 1, the connector 21 is formed with a through hole 21 a corresponding to the light emitting surface 20 d of the planar light source 20 and a recess 21 b with which the planar light source 20 is engaged. The planar light source 20 is engaged with the recess 21b with the light emitting surface 20d facing downward. Furthermore, the planar light source 20 is fixed in a state where the aluminum substrate 20a is in close contact with the mounting surface 11d of the disk portion 11a of the heat sink 11 by screwing two corners of the four locations of the connector 21. ing. Here, since the mounting surface 11d of the heat sink 11 is formed in a substantially planar shape, it can be relatively easily accommodated with the planar light sources 20 having different sizes. In the state where the planar light source 20 is attached to the attachment surface 11d, the light emitting surface 20d is orthogonal to the central axis C1.

In addition, as the planar light source 20, in addition to the above-described LED module, for example, an EL (electroluminescence), a plurality of (for example, ten or more) LED lamps arranged in a planar shape, and the like are also included.

The body 30 is formed in a substantially cylindrical shape by, for example, aluminum die casting. The upper end 30a of the body 30 has an inclined surface 30b whose outer peripheral side is inclined lower than the inner peripheral side. The inclined surface 30b faces the inclined surface 13e of the lower end 13a of the outer peripheral wall 13 of the socket holder 10 described above, and the annular air inlet A1 described above is formed between the

inclined surfaces

13e and 30b. . A flange portion 30c is formed at the upper end of the inclined surface 30b inward. The flange portion 30c corresponds to the flange portion 11i at the lower end of the leg portion 11c of the heat sink 11 described above.

The body 30 is screwed in a state where the flange portion 30c is in close contact with the flange portion 11i on the heat sink 11 side from below. As described above, the heat sink 11 and the body 30 are connected to each other through the

flange portions

11i and 30c, that is, in a state in which a large contact area is secured between the heat sink 11 and the body 30, as described later. Heat can be effectively transmitted to the body 30 side.
Next, the reflector 40 will be described. The reflector 40 is formed of, for example, aluminum in a gently curved shape based on a parabola.

Here, FIG. 7 is a diagram for explaining the focal point f and the focal length y of the parabola. FIG. 8 is a diagram for explaining the degree of opening (curve size) of the parabolas Pr5, Pr10, Pr15, and Pr20 when the focal length y is 5, 10, 15, and 20 mm. However, the parabolas Pr5, Pr10, Pr15, and Pr20 are illustrated with their respective focal points f matched. FIG. 9 is a diagram for explaining how the opening (light entrance) K in the reflector Ra formed by a parabola matched to the outer shape of the body 30 is reduced. FIG. 10 is a diagram for explaining a state in which the height H of the reflector Rb formed by a parabola having a large focal length y is lowered (length is shortened). Moreover, FIG. 11 is a figure explaining reflection of light in case the reflector Rc is an ellipse other than a parabola with respect to the reflector R of a parabola. FIG. 12 illustrates a state in which the reflecting surface of the reflector 40 is formed by combining the first reflecting surface 41 and the second reflecting surface 42, which are composed of two parabolas Pr1 and Pr2 having different focal lengths y. FIG.
The reflector 40, particularly its shape, will be described in detail with reference to FIGS.

As shown in FIG. 7, the origin of the parabola is O, the focus is f, and the distance between the origin O and the focus f is the focal length y. When the reflector R is formed by a parabola, if a point light source is placed at the focal point f, the light emitted from the focal point f is reflected by the parabola and all becomes parallel light parallel to the central axis C1. The shape of the parabola is determined by the origin O, the focal point f, and the focal length y.

FIG. 8 shows four parabolas Pr5, Pr10, Pr15, and Pr20. The position of the focal point f is the same, and the focal length y is 5, 10, 15, 20 mm in this order. As can be seen from the figure, the parabola becomes a larger curve (a curve having a larger opening on the lower end side) as the focal length y is larger.

Generally, in a lighting device such as a downlight or a spotlight, it is preferable to take a deep cut-off angle (for example, 30 ° or more) in order to reduce glare. For this purpose, as shown in FIG. 9, it is desirable to reduce the diameter D of the opening (light exit) R1 of the reflector R and increase the height (length) H of the reflector R. Furthermore, by making the height H of the reflector R long, the amount of light hitting the reflector R out of the amount of light emitted from the planar light source 20 can be increased. That is, light controllability can be improved.

Here, when the light source is a point light source, the above-described conditions can be easily satisfied. However, as in the present embodiment, the light source has a light emitting surface 20d spread in a planar shape (circular in the present embodiment). In this case, it is difficult to satisfy the above conditions. That is, if the condition is satisfied, the opening K of the reflector R becomes small, and the light emitted from the outer part of the light emitting surface 20d cannot be taken into the reflector R, and these lights are effectively used. It cannot be used.

On the other hand, as shown in FIG. 10, when a parabola having a large focal length y is adopted as the reflector R, the opening (light entrance) R2 can be increased. However, in this case, since the diameter D of the opening R1 is restricted based on the outer diameter of the body 30, the height H of the parabola of the reflector R becomes low (short), and the lower side is not a parabola. For example, it must be cylindrical. For this reason, the light which can be utilized effectively decreases.

As this countermeasure, for example, a case where an elliptic curve reflector Rc is used instead of the parabolic reflector R is shown in FIG. In this case, although the conditions can be satisfied with respect to the diameter D of the opening R1 of the reflector Rc, the size of the opening R2, and the height H of the reflector R, the light emitted from the light emitting surface 20d can be made parallel light. Can not.

Therefore, in this embodiment, as shown in FIG. 12, the reflecting surface of the reflector 40 is not formed by a single paraboloid, but a plurality of (2 in the present embodiment) each having a different curve shape (focal length y). The first reflecting surface 41 and the second reflecting surface 42 are combined.

In the reflector 40, the inner reflection surface is formed with a circular horizontal boundary line S1 as a boundary, the lower side (the side far from the planar light source 20) is formed by the first reflection surface 41, and the upper side (planar shape). The second reflecting surface 42 was formed on the side close to the light source 20. The upper end of the first reflecting surface 41 and the lower end of the second reflecting surface 42 are continuous at the boundary line S1.

The first reflecting surface 41 is formed in a parabolic shape obtained by rotating a part of the first parabola Pr1 having the central axis C1 as a symmetry axis (reference) around the central axis C1. On the other hand, the second reflecting surface 42 is formed in a parabolic shape obtained by rotating a part of the second parabola Pr2 having an axis C2 parallel to the central axis C1 as a symmetry axis around the central axis C1. ing.

Here, the intersection of the central axis C1 and the light emitting surface 20d is T1, and the intersection of the axis C2 and the light emitting surface 20d is T2. The focal point f1 of the first parabola Pr1 that is the basis of the first reflecting surface 41 is set at the intersection T1, and the focal point f2 of the second parabola Pr2 that is the basis of the second reflecting surface 42 is It is set at the intersection T2. That is, the focal points f1 and f2 are set on the light emitting surface 20d. Furthermore, the focal length y of the second parabola Pr2 is set shorter than the focal length y of the first parabola Pr1.
Further details will be described with reference to FIG. Here, FIG. 14 is a diagram illustrating the synthesis of the first reflecting surface 41 and the second reflecting surface 42.

In the present embodiment, as shown in FIG. 14, the second reflecting surface 42 has an opening surface K <b> 2 that faces the light emitting surface 20 d of the planar light source 20 through the gap G. Here, assuming that a virtual opening surface K1 is a surface formed by intersecting a virtual extension portion M1 obtained by extending the first reflecting surface 42 toward the light emitting surface 20d and the opening surface K2, the above-described opening surface K2 is a virtual surface. It is configured to be larger than the opening surface K1. Accordingly, the planar light source 20 having a larger light emitting surface 20d can be attached in order to increase the light emission amount. In this case, light emitted from the vicinity of the outer peripheral edge of the light emitting surface 20d is effectively used as the second reflecting surface 42. It becomes possible to reflect with.

Here, as the position of the intersection point T2, for example, when the radius from the center intersection point T1 to the outer peripheral edge 20e of the light emitting surface 20d is r, the point can be a radius r / 2 that is half of the radius. In this case, the second reflecting surface 42 converts the reflected light of the light emitted from the LED element located on the circumference having the radius r / 2 around the intersection T1 in the light emitting surface 20d into parallel light. be able to.
Here, with reference to FIG. 15, the magnitude relationship between the opening surface K2 and the light emitting surface 20d will be described.

As shown in the figure, a gap G is provided between the light emitting surface 20d of the planar light source 20 and the opening surface K2 of the reflector 40. This is provided for wiring a lead wire for supplying electric power to the planar light source 20 or based on a law or the like.

In the figure, three large, medium, and small light emitting surfaces 20d having different diameters (the diameter of the outer peripheral edge 20e) are illustrated. In the following description, these three planar light sources 20 have a light emitting surface 20d having a circular shape, and the center thereof coincides with the intersection T1 between the light emitting surface 20d and the central axis C1. In addition, the irradiation angle of the LED elements constituting the light emitting surface 20d is assumed to be θ (for example, 120 degrees). The diameters of the large, medium, and small light emitting surfaces 20d are 2r3, 2r2, and 2r1 in this order, and 2r3> 2r2> 2r1.

Furthermore, it is assumed that the light L2 emitted from the outer peripheral edge 20e of the light emitting surface 20d having a diameter 2r2 hits the upper end 42a of the second reflecting surface 42. According to this, the light L3 traveling outward at the irradiation angle θ from the outer peripheral edge 20e of the light emitting surface 20d having the diameter 2r3 does not strike the second reflecting surface 42 but passes outside the reflecting surface 42. On the other hand, the light L1 traveling outward at the irradiation angle θ from the outer peripheral edge 20e of the light emitting surface 20d having the diameter 2r1 hits the lower side of the upper end 42a of the second reflecting surface 42. For this reason, the part 42b where the light from the light emitting surface 20d does not hit is formed on the upper end 42a side of the second reflecting surface 42.
Here, if the diameter of the opening surface K2 is 2rk, the diameter 2r2 can be obtained by the following equation.
2r2 = 2rk−2 {Gtan (θ / 2)} (1)

That is, if the diameter 2rk of the opening surface K2, the gap G, and the irradiation angle θ are determined, this diameter 2r2 can be obtained. The light emitted from the vicinity of the outer peripheral edge 20e of the light emitting surface 20d having the diameter 2r2 thus obtained does not come off the second reflecting surface 42 and is not wasted, as is apparent from FIG. A portion 42b where no light hits the surface 42 is not formed. That is, it is preferable to dispose the planar light source 20 having the light emitting surface 20d having the diameter 2r2 that satisfies the above-described formula 1 for the opening surface K2 having the diameter 2rk.

On the other hand, a part of the light having a larger diameter than the outer peripheral edge 20e of the light emitting surface 20d having a diameter of 2r3 does not hit the second reflecting surface 42 and is wasted, but the second reflecting A portion 42b where the light does not strike the surface 42 is not formed. That is, a part of the light from the light emitting surface 20d is wasted, but substantially the entire second reflecting surface 42 is effectively used.

On the other hand, light emitted from the vicinity of the outer peripheral edge 20e of the light emitting surface 20d having a diameter of 2r1 having a smaller diameter does not hit the second reflecting surface 42 but is wasted, but the second reflecting surface 42 is inside. As a result, a portion 42b where no light is irradiated is formed. That is, the light from the light emitting surface 20d is not wasted, but a part of the second reflecting surface 42 is not used.

As described above, the diameter of the light emitting surface 20d is preferably set to 2r2 that satisfies the above-described formula (1). For example, the diameter of the light emitting surface 20d can be selected only in a stepwise manner, so that it can be satisfied. There are cases where it is not possible. In such a case, if it is desired to increase the control light by the second reflecting surface 42, it is larger than 2r2, and if it is desired to suppress the waste of light from the light emitting surface 20d, it should be smaller than 2r2. That's fine.

About the position of the above-mentioned boundary line S1, it is good to set to the position where the light irradiated with the irradiation angle of 120 degrees from the intersection T1 is lower than the height which crosses the reflector 40.

Note that the position of the intersection point T2 may be outside or inside the above example. In the above description, the example in which the reflection surface of the reflector 40 is configured by combining the first reflection surface 41 and the second reflection surface 42 has been described. Instead, for example, an intersection point T3 is set between the intersection point T1 and the intersection point T2, and a third reflection surface formed in the same manner as the second reflection surface 42 is provided with the intersection point T3 as a focal point f3. You may make it comprise combining these 1st reflective surfaces 41, the 2nd reflective surfaces 42, and a 3rd reflective surface. In this case, the reflected light of the light emitted from the light emitting surface 20d can be controlled more finely. In this case, it is assumed that the focal length of the third reflecting surface is smaller than the focal length y of the first reflecting surface 41 and larger than the focal length y of the second reflecting surface 42. In this case, the reflector becomes the second reflecting surface 42, the third reflecting surface, and the first reflecting surface 41 in order from the top. That is, the newly provided third reflection surface is located between the second reflection surface 42 and the first reflection surface 41.

For example, the reflector 40 shown in FIG. 12 may be subjected to facet processing, for example, on the inner surface side of the portion located above the boundary line S2 (see the two-dot chain line) in the second reflecting surface. Further, the inner surface side of the portion located below the boundary line S2 may be mirror-finished including the inner surface side of the first reflecting surface 41. In this way, the edge can be corrected by performing facet processing on the portion where the edge is easily attached to the reflected light.

In addition, facet processing is similarly effective not only for the reflector 40 having the first reflection surface 41 and the second reflection surface 42 described above but also for a reflector formed based on one parabola. In the COB type planar light source 20, the light emitting surface 20d has a planar shape, and the light control by the reflector is more difficult than the case of the point light source, and fine control is required. It can be an effective means for fine control.

As shown in FIG. 12, the reflector 40 has the second reflecting surface 42 inserted inside the leg portion 11c of the heat sink 11 so that the opening R2 is close to the light emitting surface 20d of the planar light source 20. Further, the reflector 40 is positioned by engaging the ring-shaped reflector fixing bracket 51 with the inner side of the lower end portion 30 e of the body 30 in a state where the first reflecting surface 41 is housed inside the body 30. . For this reason, replacement of the reflector 40 is easy. When the above-described planar light source 20 is replaced with one having a different calorific value, the reflector 40 is also replaced accordingly, but the replacement is easy.

The hood 50 is formed in a cylindrical shape, and is fixed by being screwed to the outer peripheral surface of the lower end portion 30e of the body 30. At this time, one or more filters (not shown) having various functions can be attached between the opening R1 of the reflector 40 and the upper end of the hood 50. These filters can be easily replaced by attaching / detaching the hood to / from the body 30.

As shown in FIG. 13, the luminaire 1 described above can use a lamp 62 instead of the planar light source 20. The reflector 40, the planar light source 20, and the connector 21 are removed, the base 60 is fixed to the attachment surface 11 d of the heat sink 11, the connector 61 is attached, and the lamp 62 is attached to the connector 61. Further, a reflector 63 is attached so as to cover the lamp 62. In addition, a shield 64 is attached to prevent direct light from the lamp 62. As described above, the socket holder 10 including the heat sink 11, the body 30, and the hood 50 can be used as they are, and can be easily replaced with the lamp 62.
Next, with reference to FIG. 3 to FIG. 5, the transfer of heat generated with the light emission of the planar light source 20 will be described.

Here, FIG. 3A is a plan view (top view) for explaining the heat conduction of the luminaire 1 as described above, and FIG. 3B is a view taken along the line III-III in FIG. is there. FIG. 4 is a view taken along the line III-III in FIG. 3 (A) for explaining the thermal radiation (radiation) of the luminaire 1. FIG. 5 is a view taken along the line III-III in FIG. 3A for explaining the convective heat transfer of the lighting fixture 1.
First, with reference to FIG. 3, the heat conduction in which heat moves in each member will be described.

The heat generated by the planar light source 20 is transmitted from the aluminum substrate 20a to the heat sink 11, and is further conducted from the heat sink 11 as indicated by arrows in FIG. That is, the heat generated by the planar light source 20 is sucked up by the heat sink 11 having a large heat capacity via the aluminum substrate 20a, and is mainly conducted to the outer peripheral wall 13 through the

radiation fins

12, 12,. On the other hand, a part is conducted to the body 30 and the hood 50 through the leg portions 11 c and the

flange portions

11 i and 30 c. Thus, the heat generated by the planar light source 20 is quickly sucked up by the heat sink 11 having a large heat capacity, and then diffused over substantially the entire portion of the lighting fixture 1 except for the reflector 40 through each member.

Next, the radiation of heat from each member will be described with reference to FIG. The heat transmitted to the heat sink 11, the outer peripheral wall 13, the body 30, the hood 50, and the like is efficiently radiated substantially outwardly based on the smooth outer peripheral surfaces of these members. For example, since the inclined surface 11g of the conical portion 11b of the heat sink 11 is inclined downward toward the outside, the heat radiated from the inclined surface 11g at a right angle is radiated so as to spread from the center.
Next, heat transfer by convection will be described with reference to FIG.

The heat transferred to each member by heat conduction is moved by the air flow indicated by the arrows directed upward from substantially lower in FIG. At this time, since the outer peripheral surface of the body 30 and the outer peripheral surface 13d of the outer peripheral wall 13 are formed to have substantially the same diameter, air smoothly flows from the lower side to the upper side along these outer peripheral surfaces. In addition, the gap (space) between the heat sink 11 and the outer peripheral wall 13 is surrounded by two radiating

fins

12 and 12 adjacent to each other, and is surrounded by the four sides of the front, rear, left and right, and penetrated vertically. A path A2 is formed. For this reason, the air smoothly flows from the lower side to the upper side in the flow path A2, and quickly moves the heat from the

radiation fins

12, 12,. Furthermore, since the air intakes A1, A1... Are formed narrower than the flow paths A2, A2..., The flow velocity at the air intakes A1, A1. The air flow in the flow paths A2 and A2 becomes smooth.
Here, the operation and effect of the above-described lighting fixture 1 will be organized.

(1) Since the luminaire 1 uses the planar light source 20 having the planar light emitting surface 20d as the light source, the heat generated with the light emission of the planar light source 20 is efficiently dissipated, and the surface The temperature rise of the light source 20 can be suppressed. That is, for example, the COB type planar light source 20 has the LED element mounted on the aluminum substrate 20a and can be attached in a state where the aluminum substrate 20a is in direct contact with the attachment surface 11d of the heat sink 11. . For this reason, the heat of the planar light source 20 can be absorbed by the heat sink 11 quickly and efficiently.

(2) On the outer

peripheral surfaces

11e, 11h and the inclined surface 11g of the heat sink 11, a large number of radiating

fins

12, 12,... Extending in the radial direction are provided, and the outer peripheral ends of the radiating

fins

12, 12,. By providing the outer peripheral wall 13, air flow paths A2, A2,... In the vertical direction are formed between them, so that the air flow can be made smooth and the cooling efficiency can be improved.

(3) By providing the conical inclined surface 11g at the upper end of the heat sink 11, variation in the heat transfer distance in the heat sink 11 is reduced, and heat transfer in the unnecessary direction in the heat sink 11 is reduced. Therefore, efficient heat conduction can be realized.

(4) An air intake A1 that guides air to the flow path A2 between the radiating fins 12 is formed in a gap between the socket holder 10 and the body 30 when the body 30 is attached. For this reason, in particular, it is not necessary to form a through hole in the outer peripheral wall 13, and the air intake A1 can be configured easily.

(5) By forming the air intake A1 narrower than the flow path A2, the flow velocity of the air in the vicinity including the air intake A1 can be increased, so that the flow of cooling air can be made smooth. it can.

(6) Since the heat sink 11 and the body 30 are connected to each other by the

flange portions

11i and 30c formed respectively, the contact area between the two can be increased, and the heat can be moved smoothly.

(7) The reflector 40 is formed by the first reflecting surface 41 and the second reflecting surface 42. For this reason, not only the light emitted at the intersection T1 (center) of the light emitting surface 20d of the planar light source 20, but also the light emitted at the intersection T2 far from the intersection T1, the reflected light is centered on the central axis C1. The light can be parallel light. Thus, by finely controlling the reflected light by the reflector 40, it is possible to reduce the diameter D of the opening R1 and increase the height H of the reflector 40, thereby ensuring a large glare cut angle. It becomes.

(8) For example, by applying facet processing to the inner surface of the upper end side of the reflector 40 (for example, the upper side of the boundary line S2 in FIG. 12), the edge can be reduced and the light can be made gentle. Note that this is not limited to the reflector 40 having the first reflecting surface 41 and the second reflecting surface 42. For example, a general reflector formed based on the planar light source 20 and one parabola may be used. It is the same.

(9) By configuring the reflecting surface of the reflector 40 with the first reflecting surface 41 and the second reflecting surface 42 as described above, the planar light source 20 having a large light emitting surface 20d can be used. Even in this case, the light from the light emitting surface 20d can be effectively reflected as parallel light.

(10) As shown in FIG. 13, a dedicated (special) structure for attaching the planar light source 20 and the reflector 40 to the space inside the leg portion 11c of the heat sink 11 and the space inside the body 30 is provided. Not provided. For this reason, it can replace | exchange easily for the planar light source 20 from which a magnitude | size differs, and the reflector from which a shape differs. Furthermore, as described with reference to FIG. 13, it is easy to replace the lamp 62 as a light source and the reflector 63 having a low height.

1 Lighting fixture 20 Planar light source (light source)
20d Light emitting surface 40 Reflector 41 First reflecting surface 42 Second reflecting surface C1 Central axis C2 Axis center f1 Focus of first parabola f2 Focus of second parabola K1 Aperture surface K2 Virtual aperture surface Pr1 First parabola Pr2 Second parabola M1 Virtual extension y Focal length

Claims

A light source having a planar light emitting surface orthogonal to the central axis;
A reflector that reflects light from the light emitting surface with a reflecting surface with respect to the central axis;
The reflective surface is
A parabolic first reflecting surface formed by rotating a part of a first parabola with the central axis as a symmetric axis about the central axis;
A second parabolic reflecting surface formed by rotating a part of a second parabola with an axis parallel to the central axis as an axis of symmetry about the central axis;
A lighting apparatus characterized by that.
The first reflecting surface and the second reflecting surface are arranged such that the second reflecting surface is disposed on the side close to the light source, and the first reflecting surface is disposed on the side far from the light source, Mutually continuous,
The lighting fixture according to claim 1.
The focal length of the second parabola is shorter than the focal length of the first parabola,
The lighting fixture according to claim 1 or 2, characterized by the above-mentioned.
The focal point of the first parabola and the focal point of the second parabola are set on the light emitting surface;
The lighting fixture according to any one of claims 1 to 3, wherein
The second reflecting surface has an opening surface facing the light emitting surface,
The opening surface is larger than a virtual opening surface formed by intersecting a virtual extension portion obtained by extending the first reflecting surface to the light emitting surface side and the opening surface.
The lighting fixture of any one of Claims 1 thru | or 4 characterized by the above-mentioned.