JP5743191B2 - Lighting device and lighting fixture - Google Patents

Description

  Embodiments described herein relate generally to a lighting device and a lighting fixture having a light-transmitting cover member.

  In recent years, a light emitting diode (hereinafter referred to as “LED”) is used as a light source in an illumination device having a light-transmitting cover member, in particular, a lamp with a cap, and the luminous efficiency of the LED is improved. Lighting devices such as various LED lamps and lamps have been developed which are employed as light sources for general lighting.

JP 2009-37995 A JP 200649410 A JP-A-8-273609 JP-A-6-340469

  However, in this type of lighting device, for example, an LED lamp, there is a problem that the light output is lowered and the light emission efficiency is lowered as the temperature rises. Also, in general, the LED as the light source is mounted on a flat substrate, so that the light is distributed toward the top of the globe, and the light distribution is lower than that of a general incandescent bulb. There is a problem that the corner becomes narrow. On the other hand, there is a price difference from general incandescent bulbs, and further cost reduction is required. For this reason, in an illuminating device such as an LED lamp, an important issue is how to achieve further higher output, wider light distribution, and cost reduction.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a lighting device and a lighting fixture capable of achieving high output, wide light distribution, and cost reduction.

The illuminating device of embodiment comprises a main body, a light emission part, and a translucent cover member. The main body is made of a heat conductive member. Emitting portion is disposed in the main body. Translucent cover member is provided so as to cover the light emitting portion, made of ceramic having a light-transmitting member to be joined of a translucent bonding material containing glass hemisphere and hemisphere.

  ADVANTAGE OF THE INVENTION According to this invention, the illuminating device and lighting fixture which can aim at high output, wide light distribution, and cost reduction can be provided.

1 shows an illuminating device according to an embodiment of the present invention, wherein (a) is a top view showing a state where a cover member is removed, (b) is a longitudinal sectional view, and (c) is an enlarged view of portion B in FIG. Sectional drawing shown, (d) is a sectional view showing the portion A in FIG. The front view of the illuminating device which is embodiment of this invention. The cover member of an illuminating device is shown, (a) is a longitudinal cross-sectional view, (b) is a cross-sectional view of a 1/2 spherical body mold, (c) is a cross-sectional view of a 1/4 spherical body mold. FIG. 3A shows a cover member of the lighting device, FIG. 3A is a cross-sectional view showing alignment means, FIG. 3B is a cross-sectional view showing a first modification of the alignment means, and FIG. 2C is a second modification of the alignment means. Sectional drawing which shows an example, (d) is sectional drawing which shows the 3rd modification of the alignment means. The illuminating device is shown, (a) is a cross-sectional view showing the engaging means in an enlarged manner, (b) is a perspective view showing a cutout portion of the engaging means, and the main body viewed from above. The illumination device is schematically shown, wherein (a) is a front view of the cover member, (b) is a bottom view of the cover member, (c) is a side view of the cover member forming die, and (d) is a cover member forming die. FIG. The graph which shows the thermal-analysis result by the simulation of an illuminating device, (a) is a graph which shows the change of the thermal resistance by a radiator / ceramics glove ratio at the time of using a ceramics optical cover, (b) is the conventional polycarbonate optical cover The graph which shows the change of the thermal resistance by the heat radiator / polycarbonate glove ratio at the time of using. The graph which combined and showed the thermal-analysis result of the ceramics optical cover and polycarbonate optical cover of FIG. 7 (a) (b). Sectional drawing which showed schematically the state which installed the lighting fixture equipped with the illuminating device on the ceiling. The modification of an illuminating device is shown, (a) is a longitudinal cross-sectional view of the cover member which shows a 1st modification, (b) is a longitudinal cross-sectional view of the cover member which shows a 2nd modification.

  Hereinafter, embodiments of a lighting device and a lighting fixture will be described with reference to the drawings.

  First, the configuration of the lighting device will be described. The illuminating device of this embodiment comprises the small cap lamp 10 which can be substituted for the mini krypton bulb 60W with an E17 cap, for example. As shown in FIGS. 1-6, the main body 11 which consists of a heat conductive member, the light emission part 13 which is arrange | positioned in the main body and has the solid light emitting element 12, the light transmission part which is provided so that the light emission part may be covered, and consists of ceramics The cover member 14 is used.

  The main body 11 needs to have a certain rigidity in order to support the light emitting unit 13, the lighting device 15, and the base member 16, which will be described later, and to dissipate heat from the light emitting unit 13 and the lighting device 15. Thermal conductivity is required. In order to satisfy these conditions, the main body 11 is made of aluminum in the present embodiment. The main body 11 made of aluminum has a cylindrical shape with a substantially circular cross-sectional shape, and is integrally formed with a storage portion 11c having an opening portion 11a having a large diameter on one end side and an opening portion 11b having a small diameter on the other end side. To do. Further, as shown in FIG. 2, the outer peripheral surface of the main body 11 is formed so as to form a substantially conical taper surface whose diameter gradually decreases from one end side to the other end side, and the outside is a neck portion in the mini krypton bulb. The shape is approximated to the silhouette. The aluminum main body 11 having such a configuration is manufactured, for example, by casting, forging, cutting, or the like, and is configured as a cylindrical body having an open end with a space inside.

  The opening 11a on one end side of the main body 11 is integrally formed with a substrate support portion 11e in which the surface of the concave step portion is formed to be a flat surface so that an annular concave step portion is formed. The protruding ridge portion 11f is formed integrally. In addition, the housing recess 11c formed integrally with the main body 11 forms a space for arranging a circuit board constituting the lighting device 15 to be described later, and the cross section is the central axis x− of the main body 11. It has a substantially circular shape centered on x, and has a substantially truncated cone shape whose inner diameter decreases from one end side toward the other end side. An insulating case 20 is fixed in the storage portion 11c in order to achieve electrical insulation between the lighting device 15 and the main body 11.

  The insulating case 20 is made of a heat-resistant and electrically insulating synthetic resin such as PBT (polybutylene terephthalate), and an opening 20a is formed on one end side and the other end side is closed, and the inner surface shape of the storage portion 11c is formed. Is formed into a shape having a substantially truncated cone shape with a bottom substantially matching the above. And it protrudes from the opening part 11b by the side of the other end part of the main body 11, and the opening part 20a is pressed by the board | substrate 13a mentioned later, and is fixed in the accommodating part 11c. You may make it fix in the accommodation recessed part 11c with screws, or adhesives, such as a silicone resin and an epoxy resin. Further, the insulating case 20 is integrally formed with a base attaching portion 20c having a stepped outer periphery on the other end side.

  In the present embodiment, the solid-state light emitting element 12 includes a light-emitting diode (hereinafter referred to as “LED”), and in the present embodiment, includes four SMD (Surface Mount Device) type LEDs. The LED may be a so-called COB (Chip on Board) type in which a plurality of LED chips and phosphors excited by the LED chips emit white light (including daylight white color, daylight color, and light bulb color). Good.

  The light emitting unit 13 has a metal with good thermal conductivity, in this embodiment, an aluminum substrate 13a having a flat circular plate shape, and on the upper surface of the surface (FIG. 1B). A wiring pattern made of a copper foil is formed through an electrical insulating layer such as silicone resin, and the four LEDs 12 are arranged on the wiring pattern so as to be substantially concentric and mounted. As a result, the light-emitting unit 13 including the light-emitting module in which the four LEDs 12 are arranged substantially symmetrically is formed on the circular and plate-like substrate 13a (FIG. 1A).

  The light emitting unit 13 configured as described above passes through an electrical insulating sheet or the like (not shown) made of silicone resin or the like in order to electrically insulate the substrate support part 11e formed on one end side of the main body 11. Then, it is fixed in close contact with the surface of the substrate support portion 11e having a flat surface by using a fixing means 13b such as a screw. Thereby, the light emission part 13 is closely_contact | adhered and fixed to the board | substrate support part 11e.

  As a result, the light emitting unit 13 is disposed on one end side of the main body 11, the back surface of the substrate 13 a is securely adhered to the substrate supporting unit 11 e of the main body 11, and the substrate 13 a is made of aluminum having good thermal conductivity. In combination with this, heat generated mainly from the back surface side of the LED 12 can be effectively transmitted to the main body 11 to be dissipated. With the above-described configuration, the light axis y of the light emitting unit 13 including the substrate 13a on which the four LEDs 12 are mounted substantially coincides with the central axis xx of the main body 11, and has a light emitting surface that is substantially circular as viewed from above. The part is composed.

  The cover member 14 constitutes the globe of the lamp, has a light-transmitting property, and needs to have heat conductivity in order to dissipate heat generated from the light-emitting unit 13 and the like. Since a cover function for protection is required, the cover is made of a member having a certain rigidity. A material that is particularly effective as a member that satisfies these conditions is alumina. In this embodiment, the material is composed of translucent ceramics mainly composed of translucent alumina polycrystal. An alumina material is a material with good light resistance and good light transmittance. In general, impurities are often mixed, but in view of light transmission and light diffusibility, it is better to mold using an alumina raw material having a purity as high as possible (99 to 99.99%). Moreover, light diffusion can also be changed by changing the diameter of the alumina particles of the raw material. Alumina itself is a material having a very high total transmittance of 85 to 95%, but what is used in this embodiment is a sintered polycrystalline body of alumina fine particles having a refractive index of about 1.8. An arbitrary light diffusivity can be obtained by changing the particle size. Furthermore, since the thermal conductivity increases when the material purity is high, it is preferable to use a high-purity alumina raw material both optically and thermally.

  Considering the advantages of the alumina material, in the present embodiment, for example, translucent ceramics used for arc tubes such as sodium lamps and metal halide lamps, that is, sapphire, translucent polycrystalline alumina ceramics (aluminum oxide) Product), yttrium-aluminum-garnet (YAG), yttrium oxide (YOX), and translucent ceramics composed mainly of an alumina polycrystal composed of aluminum nitride (AlN).

  As shown in FIG. 3A, the cover member 14 made of translucent ceramics having these configurations is provided so as to cover the light emitting portion 13, and has a translucent member joined to the hemisphere and the hemisphere.

  That is, in this embodiment, the hemisphere is composed of a half sphere 14-1 that is joined to the sphere by a line zz connecting the largest diameter portions D and D, and the translucent member that is joined to the hemisphere. In this embodiment, the sphere is composed of a ¼ sphere 14-2 joined by a line zz connecting the maximum diameter portions D and D. The translucent member joined to the hemisphere is preferably at least part of a sphere to form a substantially spherical glove, but has a shape such as a cylinder other than a sphere. There may be.

  The cover member 14 made of ceramics is formed by molding and firing powdered ceramics. Therefore, like a conventional cover member made of synthetic resin such as polycarbonate, the cover member 14 is blown to form a sphere and molded. Can not do it.

  For this reason, as shown in FIG. 3 (b), the sphere is molded with the maximum diameter portions D and D so that each of the spheres becomes a half sphere so that the mold K3 can be removed. There is a need. On the other hand, from the optical demand for realizing wide light distribution, it is necessary to form not only the ½ sphere 14-1 but also a glove shape as close to the sphere as possible. In the case of a lamp with a cap, since it is necessary to mount the light emitting portion 13, the cover member 12 is actually formed into a substantially spherical shape by covering the quarter sphere and joining them together. The quarter sphere 14-2 is molded so that the mold K4 can be removed as shown in FIG. 3C, similarly to the half sphere 14-1.

  On the other hand, from the viewpoint of cost, it is necessary to improve the manufacturability of the work for joining these ½ spheres and ¼ spheres, particularly the work for aligning the joints of both. For this reason, in the present embodiment, the alignment means 18 that can be automated is formed at the joint between the two.

  As shown in FIG. 4 (a), the alignment means 18 in the present embodiment is a ridge that forms a ring along the joint with respect to the joint that forms the ring of the 1/2 sphere 14-1. 18a is integrally formed, and a concave groove 18b having a ring shape is integrally formed along the joint portion with respect to the joint portion having a ring shape of the quarter sphere 14-2. The positioning is performed by fitting into the groove 18b. According to this configuration, for example, if an adhesive is injected into the concave groove 18b, the bonding process can be performed simultaneously with the reliable alignment, and the operation is simple and can be easily automated. As a result, workability for joining is improved, manufacturability is increased, and manufacturing costs can be reduced.

  As shown in FIG. 4 (b), the ridges 18a and the concave grooves 18b are, on the contrary, the ridges 18a to the ¼ sphere 14-2 and the concave grooves 18b to the ½ sphere 14-1. Each may be formed. Further, as shown in FIGS. 4C and 4D, the aligning means 18 may be configured by forming the ridges 18a and the grooves 18b by the stepped portions, and further, facing the respective joints. Thus, a plurality of pins and pin holes into which the pins are inserted may be formed, and the alignment may be performed by inserting them together.

  Since ceramics are difficult to be joined by means such as ultrasonic welding as in the case of a conventional synthetic resin cover member, the two are firmly joined by a translucent joining material 19 (FIG. 4). ). In particular, the light-transmitting property makes it difficult for shadows to be generated at the joints, and it is possible to improve the lamp illumination atmosphere and commerciality by making the joints inconspicuous. As the bonding material 19 having translucency, an adhesive made of a glass filler-containing paste is suitable. According to this adhesive, by heating after bonding, the paste components fly away and only the glass remains, so that the light transmittance at the joint is high, and the generation of shadows can be minimized. At the same time, since glass has a higher thermal conductivity than synthetic resin, heat transfer loss at the joint can be minimized. Further, as the bonding material 19, a material having further thermal conductivity, heat resistance, and light resistance is preferable. In particular, with respect to thermal conductivity, the cover member 12 of the present embodiment uses the thermal conductivity of ceramics to dissipate the heat of the light-emitting unit 13, so heat transmission loss at the joint is reduced as much as possible. It becomes possible not to disturb the effect.

  As described above, the cover member 14 in the present embodiment is configured in a shape that forms a substantially 3/4 sphere with the lower portion of the sphere cut. The approximately 3/4 sphere is a zz line connecting the maximum diameter portions D and D of the sphere, and approximately 1/2 sphere 14-1 and approximately 1/4 sphere 14-2 are joined. And each is shape | molded and baked with a type | mold as mentioned above, and it is comprised by the zz line | wire which connects the largest diameter parts D and D, and is comprised so that it may become a substantially 3/4 spherical body.

  As described above, the cover member 14 is configured to have a substantially 3/4 sphere, so that the light distribution angle can be widened. That is, as indicated by an arrow in FIG. 1B, the light a radiated from the light emitting unit 13 passes through the lower part of the approximately 3/4 sphere, that is, approximately the 1/4 sphere 14-2, and the back direction of the lamp. In other words, it is possible to radiate in the direction of the base of the lamp, to obtain a wide-angle light distribution from the top T of the lamp to the direction of the base, and to improve the light distribution that is offset toward the top of the conventional globe, It is possible to approximate the light distribution of an incandescent bulb.

  As described above, the cover member 14 has an approximately 3/4 sphere having an opening 14a on one end side, has a smooth curved surface shape approximated by the silhouette of the globe of the mini-krypton bulb as a whole, and has light diffusibility. Configured to be a milky white glove.

  As described above, by using translucent ceramics mainly composed of alumina polycrystal as the cover member 14, the cover member that has not conventionally contributed to heat dissipation can be effectively used to produce a solid light emitting element. The generated heat can be effectively dissipated and the luminous efficiency can be improved. Incidentally, in the past, this kind of cover member, for example, a globe, although the surface area occupies a ratio of about 30 to 40% with respect to the entire surface area of the lamp with cap, these materials are: Since glass or synthetic resin was used, the thermal conductivity was low, and it did not contribute to enhancing the heat dissipation effect. On the other hand, according to the present embodiment, the cover member occupying a ratio of about 30 to 40% as the surface area is made of translucent ceramics mainly composed of an alumina polycrystal having excellent thermal conductivity. Therefore, it is possible to improve the heat dissipation of the entire lamp, and it is possible to configure a lighting device such as a lamp with a cap with higher efficiency and higher output. In particular, in the present embodiment, by making the cover member 14 approximately 3/4 sphere, the surface area for heat dissipation can be made wider than the conventional 1/2 sphere, and more effective heat dissipation is performed. It becomes possible to configure a lamp with a cap with even higher efficiency and higher output, that is, a lighting device. Moreover, in this embodiment, by using the joining material 19 having translucency and heat conductivity at the joint part of the sphere, the heat transfer loss at the joint part is reduced as much as possible, thereby inhibiting the heat dissipation effect. It becomes possible not to do.

  And the cover member 14 comprised above is fixed to the opening part 11a of the main body 11 so that the light emission part 13 may be covered, in order to protect the light emission part 13. FIG. This fixing is performed by joining the aluminum body 11 made of a rigid body to the cover member 14 made of ceramic, which is also made of a rigid body, so that the heat of the light emitting portion 13 is more efficiently transmitted from the body 11 to the cover member 14. Since it is necessary to make it, it couple | bonds as follows.

  That is, as shown in FIG. 5, since the rigid main body 11 and the cover member 14 are difficult to bond using, for example, a highly flexible material such as a synthetic resin, the thermal conductivity is good. Bonded by adhesive. Further, the engaging means 17 including a groove 17a and a protrusion 17b provided to face the main body 11 and the cover member 14 so that the positions of the cover member 14 and the main body 11 do not shift due to long-term creep (heat). Is fixed mechanically.

  The engaging means 17 is formed on the inner peripheral surface of the opening on the one end side of the main body 11, that is, on the outer peripheral surface of the cover member 14 and the ring-shaped groove portion 17 a formed integrally with the inner peripheral surface of the protrusion 11 f. It consists of the protruding part 17b. The groove 17a has a notch 17a1 (FIGS. 1A and 5B) for inserting the protrusion 17b of the cover member 14, and the notch 17a1 is symmetric with respect to the center O of the main body 11. A pair of two is formed by being cut out integrally.

  As schematically shown in FIGS. 6A and 6B, the protrusion 17b is formed on the outer peripheral surface of the cover member 14 so as to project integrally with the center O ′ of the cover member. The inclined portion 17b1 is formed of a pair of projecting pieces so as to have a taper shape with a closing angle with respect to the groove portion 17a direction of the main body 11, and a ring-shaped step portion 17b2 is integrally formed above the projecting portion 17b. The The inclined portion 17b1 includes an inclined portion formed on the upper surface of the projecting portion 17b and inclined portions formed on both side surfaces, and the inclination angle is about the draft angle of a mold used for forming a globe made of translucent ceramics. If the angle is satisfied.

  Then, the pair of protrusions 17b of the cover member 14 and the pair of notches 17a1 of the main body 11 are aligned, and the protrusion 17b is inserted into the groove 17a from the notch 17a1 and rotated by a predetermined angle (left and right). Either way) As a result, as shown in FIG. 5A, the protrusion 17b is engaged and mechanically coupled in the groove 17a, and the positional displacement between the cover member 14 and the main body 11 due to long-term creep (heat) occurs. Is prevented. The adhesive S is preferably applied to the groove portion 17a of the main body 11. As the adhesive, an adhesive made of a silicone resin or an epoxy resin having heat conductivity and heat resistance is preferable.

  Further, by engaging the groove 17a and the protrusion 17b, the wall surface 17a2 of the lower surface of the groove 17a is joined and thermally connected to the lower surface 17b3 of the protrusion 17b, and at the same time, the lower surface of the step 17b2 of the cover member 14 Are joined to and thermally connected to the opening end face 11a1 of the opening 11a of the main body 11. Even if a slight gap is formed in these thermally connected portions, the adhesive S enters the gap, so that the thermal connection is maintained. By these actions, the heat of the light emitting portion 13 transmitted to the main body 11 is efficiently transmitted to the cover member 14 by the thermal connection with the main body 11 by the adhesive S having thermal conductivity and the engaging means 17. Can do.

  The space P having a triangular cross-section formed by the engagement of the groove 17a and the protrusion 17b serves as a reservoir for the adhesive and prevents the adhesive S from protruding to the outside. Become. At the same time, since the space portion P is filled with the adhesive S, it is more firmly fixed, and the heat of the light emitting portion 13 transmitted to the main body 11 by the filled adhesive having thermal conductivity, Further, it can be efficiently transmitted to the cover member 14.

  As described above, the aluminum main body 11 made of rigid bodies and the ceramic cover member 14 can be firmly fixed by the engaging means 17, and the positional deviation between the cover member 14 and the main body 11 is prevented. The member 14 can reliably cover the LED 12 of the light emitting unit 13 over a long period of time. Furthermore, the heat of the light emitting portion 13 can be efficiently transmitted to the cover member 14 by the engaging means 17 to be radiated. As a result, the cover member 14 made of translucent ceramics transmits the light emitted from the LED 12 with a wide-angle light distribution extending from the apex T of the lamp to the base direction while diffusing the light, and mainly the surface of the LED 12. The heat generated from the side is radiated to the outside from the large surface area of the approximately 3/4 sphere. At the same time, the cover member 14 is connected to the opening 11a of the main body 11 by the engagement means 17 so that heat conduction is possible, and heat generated mainly from the back side of the LED 12 is transferred from the main body 11 to the cover member 14. By conducting heat to dissipate heat, an effective heat dissipating action is performed, and a decrease in the light emission efficiency of the LED can be suppressed, and high output can be achieved.

  In addition, the engaging means 17 is formed with a pair of protrusions 17b having symmetry with respect to the center O ′ of the cover member on the outer peripheral surface of the cover member 14, and further having an inclined portion 17b1. Therefore, as shown in FIGS. 6 (c) and 6 (d), a complicated mold is used for the ceramic cover member 14 mainly composed of alumina polycrystal by the two-piece split molds K1 and K2. Therefore, the productivity can be further improved, and a cost-effective lighting device can be configured.

  As shown in FIG. 1B, the lighting device 15 includes a flat circuit board 15a on which circuit components constituting the lighting circuit of each LED 12 are mounted. The lighting circuit is configured to convert the AC voltage 100V into a DC voltage 24V and supply a constant DC current to each LED 12. The circuit board 15a is formed in a strip-like vertically long shape, and a circuit pattern is formed on one or both sides, and a lighting circuit such as a lead part such as a small electrolytic capacitor or a chip part such as a transistor is formed on the mounting surface. For this purpose, a plurality of small electronic components 15b are mounted. And in the insulating case 20 provided in the storage recess 11c of the main body 11 described above, the circuit board 15a is accommodated in the vertical direction, and the thermal conductivity of silicone resin, epoxy resin, etc. is good and the electrical insulating property. A good adhesive 15c is filled, and the circuit board 15a and the electronic component 15b are embedded and fixed. As a result, the heat generated from each electronic component 15b is dispersed and saturated inside the adhesive to be uniformized. In addition, power supply lead wires (not shown) for supplying power to the respective LEDs 12 are connected to the output terminals of the circuit board 15a, and input lines (not shown) are connected to the input terminals.

  The base member 16 connected to the lighting device 15 and provided on the other end side of the main body 11 is an Edison-type E17 base as shown in FIG. A shell portion 16a and a conductive eyelet portion 16c provided at the top of the lower end of the shell portion via an electric insulating portion 16b are provided. The opening of the shell portion 16a is fitted from the outside into the base mounting portion 20c of the insulating case 20, and is electrically insulated from the main body 11 by means such as adhesion or caulking with an adhesive such as silicone resin or epoxy resin. It is fixed to the other end side. An input line derived from an input terminal of the circuit board 15a in the lighting device 15 is connected to the shell portion 16a and the eyelet portion 16c.

  As a result, the one end of the main body 11 has a glove composed of a cover member 14 made of a translucent ceramic mainly composed of milky white alumina polycrystal and made of approximately 3/4 sphere, and the LED 12 is used as a light source. The light-emitting part 13 is provided, the E17 base member 16 is provided on the other end side, and the light bulb-shaped lamp 10 with a base whose overall appearance is approximated by the silhouette of the mini-krypton light bulb 60W is configured (FIG. 2). ). The total length L1 of the lamp with cap is about 67 mm, and the outer diameter D1 of the cover member 14 is about 35 mm.

  In general, in a lighting device such as a lamp with a seed using an LED as a light source, a large amount of light and a wide light distribution are progressing. However, in the case of a lamp with a base, it is infinitely large in order to adapt to various instruments. Can not. For this reason, since the area of the heat radiating portion is determined due to dimensional limitations, there is a limit to increasing the amount of light. On the other hand, since a wide light distribution equivalent to that of a general incandescent bulb is required, when the glove is enlarged, the main body becomes smaller and it is difficult to secure a heat radiation area. For this reason, it is difficult to develop a lamp with a cap that satisfies both high output and wide-angle light distribution.

  Therefore, in order to expand the light distribution without expanding the optical part area, it has been attempted to provide a lens above the LED element. However, since the heat radiating portion area is limited to the heat radiating surface area of the heat radiating body (main body) formed of aluminum, the heat radiating capacity cannot be obtained sufficiently, and there is a limit to increasing the amount of light. In recent years, light radiation paints and the like that improve radiation heat dissipation have been developed, but the performance is improved only to the extent of improvement in radiation capacity.

  For this reason, when trying to dissipate heat with a general incandescent bulb size, even when a 100 lm / W LED is used, the input power of 10 to 12 W becomes the limit in terms of lamp input power. If the internal temperature of the lamp rises too much, the deterioration of solder and components will be promoted and the product life will be shortened.

  On the other hand, the lamp with cap 10 configured as described above, that is, the illuminating device, has an optical glove that has not conventionally contributed to heat dissipation, that is, a cover member 14, and a heat conductive material, that is, an alumina polycrystalline body as a main component. By applying the translucent ceramics, the entire lamp becomes a heat radiating structure. By increasing the heat radiating area as compared with the prior art, it is possible to increase the amount of light. Further, by reducing the size of the heat dissipating body itself, that is, the main body 11 to increase the area for extracting light, it is possible to extract light with a wider light distribution than before.

  However, the aluminum main body 11 constituting the heat radiating body has a thermal conductivity of 80 to 150 W / m · K, but the ceramic globe has a slightly low thermal conductivity of 10 to 30 W / m · K. Area design for heat dissipation is required. The ceramic glove can be used as an optical cover even if it is thin. However, when it is used for the purpose of heat dissipation, there is an optimum thickness because it becomes a thermal resistance if the thickness is thin.

  Therefore, as described above, in order to obtain high output and wide light distribution in the lamp with cap 10 using the cover member 14 made of translucent ceramic mainly composed of alumina polycrystal, that is, the lighting device. In other words, the ratio of the surface area of the main body 11 serving as a heat radiating body and the cover member 14 serving as an optical cover, and the thickness of the cover member 14 made of translucent ceramic mainly composed of alumina polycrystal are obtained. An experiment by simulation was performed.

  In this experiment, the conditions for achieving high output of the lamp, that is, the ratio of the surface area that can obtain the optimum thermal resistance of the entire lamp, that is, the entire apparatus composed of the main body 11 and the cover member 14, The wall thickness was determined. In this experiment, the thermal resistance (K / W) was determined by LED junction temperature / lamp input power. The thickness dimension of the cover member 12 was determined as the thickness dimension t1 at the glove top T.

  The thermal analysis result by the said experiment is shown with the graph of FIGS. That is, the graph of FIG. 7A shows a change in thermal resistance depending on a radiator / ceramic globe ratio (surface area ratio) when a ceramic optical cover is used. That is, changes in thermal resistance due to the ratio of the main body 11 / cover member 14 (surface area ratio) when translucent ceramics mainly composed of the polycrystalline alumina of the present embodiment are used as the cover member 14 are shown. In the graph, a curve a indicates a change in thermal resistance when the thickness of the ceramic optical cover is 1 mm, and a curve b indicates a change in thermal resistance when the thickness of the ceramic optical cover is 2 mm.

  According to this, it can be seen that the thermal resistance is almost 6 K / W or less when the ceramic optical cover is used. In addition, the thermal resistance increases due to the thickness of the ceramic optical cover.

  Moreover, the graph of FIG.7 (b) shows the change of the thermal resistance by the heat radiator / polycarbonate glove ratio (surface area ratio) at the time of using the conventional polycarbonate optical cover. In the graph, a curve c indicates a change in thermal resistance when the thickness of the polycarbonate optical cover is 1 mm, and a curve d indicates a change in thermal resistance when the thickness of the polycarbonate optical cover is 2 mm.

  According to this, the conditions for achieving a thermal resistance of 6 K / W or less are narrow, and the surface area of the optical cover tends to be small. When the surface area ratio is small, that is, when the polycarbonate optical cover is large, the thermal resistance becomes extremely large. It gets bigger. In addition, the graph of FIG. 8 shows the thermal analysis result of the ceramic optical cover and the polycarbonate optical cover together. As described above, it has been proved that using a ceramic optical cover, that is, translucent ceramic mainly composed of alumina polycrystal as a cover member, it is possible to achieve higher output than conventional products. . In addition, it was found that by increasing the area of the ceramic optical cover, the thermal resistance is reduced and a wide light distribution is possible.

  From the above results, in order to increase the output of the lamp with cap 10 in the present embodiment, that is, the lighting device, the thermal resistance of the entire device composed of the main body 11 and the cover member 12 is 6 K / W or less. The surface area ratio of the main body 11 and the cover member 14 is 0.2 to 1.5, preferably 0.3 to 1, and the wall thickness t1 of the cover member 14 is preferably 0.5 to 3 mm. It has been found that it is optimal to configure the thickness of 1 to 2 mm.

  Next, the structure of the lighting fixture which used the lamp | ramp 10 with a nozzle | tip comprised as mentioned above as a light source is demonstrated. As shown in FIG. 9, reference numeral 30 denotes an existing downlight type lighting fixture that is embedded in a ceiling surface X of a store or the like and uses a mini-krypton bulb having an E17-shaped base as a light source. In this lighting fixture, a metal box-like fixture body 31 having an opening 31a on the lower surface, a metal reflector 32 fitted into the opening 31a, and an E17 cap of a mini-krypton bulb are screwed in. It is comprised with the socket 33 which can be. The reflector 32 is made of, for example, a metal plate such as stainless steel, and a socket 33 is installed at the center of the upper surface plate of the reflector 32.

  In the existing lighting fixture 30 for a mini-krypton bulb configured as described above, a bulb-shaped lamp with a cap 10 that uses the above-described LED as a light source is used instead of the mini-krypton bulb for energy saving and long life. . That is, since the cap-equipped lamp 10 has the cap member 16 in the shape of E17, it can be directly inserted into the socket 33 for the mini-krypton bulb of the above-mentioned lighting fixture. At this time, the outer peripheral surface of the lamp with cap 10 forms a substantially conical tapered surface, and the appearance is configured to be approximated by the silhouette of the neck portion of the mini-krypton bulb. Can be inserted smoothly without hitting the reflector 32, etc., and the application rate of the light bulb-shaped lamp with cap 10 to the existing lighting fixture is improved. Thereby, an energy-saving downlight using an LED as a light source is configured. Of course, a new downlight may be configured in the same manner as described above.

  When the power is turned on in this state, power is supplied from the socket 33 through the base member 16 of the lamp with base 10, the lighting device 15 is operated, and a DC voltage of 24 V is output. This DC voltage is applied to each LED 12 from the lighting device 15, and a constant DC current is supplied to light all the LEDs 12 simultaneously.

  The white light emitted from each LED 12 is emitted substantially uniformly toward the entire inner surface of the cover member 14. In particular, the cap-equipped lamp 10 of the present embodiment has a cover member 14 made of translucent ceramics mainly composed of an alumina polycrystal composed of approximately 3/4 spheres. While radiating with a wide-angle light distribution from T to the base direction, light is diffused by a glove made of milky white translucent ceramics, and illumination with light distribution characteristics approximated by a mini-krypton bulb can be performed. Further, the substrate 13a has a plate shape, the LED 12 is mounted on the surface thereof, and the back surface is enclosed in the substrate support portion 11e formed of a concave step portion on one end portion side of the main body 11, so that the substrate 13a is the inner surface of the globe. Therefore, the substrate 13a does not obstruct the light distribution characteristics. In particular, when the light distribution of the lamp with cap 10 serving as the light source approaches the light distribution of the mini-krypton bulb, the amount of light irradiated to the reflector 32 in the vicinity of the socket 33 disposed in the lighting fixture 30 increases, and the mini It is possible to substantially obtain the instrument characteristics as the optical design of the reflector 32 configured for the krypton bulb.

  In addition, the glove, which is integrally formed with translucent ceramics, makes it easier to obtain optical homogeneity, can diffuse light more evenly, and approximates to a mini-krypton bulb, or more than that. Illumination can be performed. Moreover, it has sufficient heat resistance and mechanical strength, and is not easily damaged by vibration during transportation.

  At the same time, when the bulb-shaped lamp with cap 10 is turned on, the temperature of the LED 12 rises and heat is generated. The heat, that is, the heat generated mainly from the surface side of the LED 12 is radiated to the outside from the cover member 14 made of a translucent ceramic mainly composed of alumina polycrystal. In particular, since the lamp with cap 10 of the present embodiment has the cover member 14 made of translucent ceramics mainly composed of an alumina polycrystal composed of approximately 3/4 spheres, heat is effectively radiated from a large surface area. Further, the heat generated mainly on the back surface side of the LED 12, that is, on the back surface side of the substrate 13a, is transmitted from the substrate 13a made of aluminum having good thermal conductivity to the substrate support portion 11e to which the substrate is directly adhered and fixed. The heat is radiated to the outside from the outer peripheral surface of the main body 11 made of aluminum. The temperature rise of the LED 12 is suppressed by these effective heat dissipation actions.

  In particular, in the present embodiment, the heat from the light emitting portion 13 transmitted to the main body 11 is efficiently transmitted to the cover member 14 by the thermal connection between the main body 11 and the cover member 14 by the engaging means 17. Since the heat generated mainly from the back side of the LED 12 can be transferred from the main body 11 to the cover member 14 to dissipate heat, a more effective heat dissipating action is performed and the temperature rise of the LED 12 is further suppressed. A reduction in luminous efficiency in the lamp with cap is suppressed. Thereby, bright illumination with high output can be performed as a downlight. In particular, according to the present embodiment, the joint portion of the cover member 12 made of a substantially 3/4 sphere of the lamp with cap 10 is joined by the joint material 18 having translucency, and thus the light transmittance at the joint portion. Lighting fixtures that are high in brightness, have almost no shadows, can be illuminated without shadows, and do not feel uncomfortable even when looking up at the lamp, and do not impair the merchantability and lighting atmosphere of the fixtures Can be configured.

  As described above, according to the present embodiment, the cover member 14 is made of translucent ceramic mainly composed of alumina polycrystal, and the sphere is joined at the maximum diameter portion, so that it is formed into a substantially 3/4 sphere. The light emitted from the LED can be distributed at a wide angle to obtain a wide light distribution, and the heat generated from the LED can be effectively dissipated, and the decrease in light emission efficiency is suppressed and increased. It is possible to provide an illumination device such as a lamp with a cap that can be output. Further, since the cover member 14 is formed with the alignment means 18 at the joint portion, it becomes possible to improve the manufacturability and to reduce the cost.

  The cover member 14 is made of translucent ceramic having a small thermal expansion coefficient (alumina: 6.0 × 10 −6 / ° C.), and the cover member 14 is engaged with the adhesive S with respect to the main body 11. Since it is firmly fixed by the combining means 17, it is possible to reliably prevent the natural fall of the cover member due to heat cycle expansion caused by repeated lighting and extinguishing of the lamp. With these functions, it is possible to provide various lighting devices such as a lamp with a cap that can ensure thermal reliability for suppressing a decrease in luminous efficiency and mechanical reliability in the cover member. Become.

  Further, since the translucent ceramic is excellent in heat resistance and has high mechanical strength, the cover member 14 can be easily melted even when internal pressure is applied to the cover member 14 due to a temperature rise particularly at the end of the life. It is possible to construct a lamp with a cap that is safe without breakage. In addition, the translucent ceramics constituting the cover member 14 can be sufficiently integrally formed, the cover member 14 having various shapes can be easily constructed, and a lighting device such as a lamp with a cap suitable for mass production, and A luminaire can be provided.

  As described above, in the present embodiment, as illustrated in FIG. 10A, the cover member 14 may be joined in the vertical direction along the vertical line yy at the maximum diameter portions D and D. Moreover, as shown in FIG. 10B, the cover member 14 may be joined along the diagonal direction at the maximum diameter portions D and D. According to these configurations, since there is no joined portion of the joined cover member in the heat transfer path extending from the joint portion of the main body 11 and the cover member 14 to the vertex T of the cover member 14, the main body 11 is moved to the cover member 14. It is possible to minimize the heat transfer loss. Moreover, although the cover member 14 was joined to 2 pieces, you may make it join more finely, such as 3 pieces, 4 pieces.

  Moreover, in this embodiment, in the main body 11 of a lamp | cap | die with a nozzle | cap | die, the outer surface part exposed outside is formed in unevenness or a satin shape, for example, and a surface area is enlarged, or white coating or a white alumite process is performed. You may make it raise the thermal emissivity of an outer surface part. Further, when white coating or white alumite treatment is applied, when the bulb-shaped lamp with cap 10 is mounted on the lighting fixture 30 and lit, the reflectance of the outer surface of the aluminum body 11 exposed to the outer surface becomes high. In addition, it is possible to increase the efficiency of the appliance, and the appearance and design are also improved, so that the merchantability can be improved.

  Further, in the present embodiment, the lighting device includes a bulb-shaped lamp with a cap (A type or PS type) approximated to the shape of a general incandescent lamp, a ball-shaped lamp with a cap (G type), and a cylindrical cap. A lamp (T type), a ref type lamp with a base (R type), or a flat thin structure lamp using a GX53 base may be used. Further, the present invention is not limited to a lamp with a cap approximated to the shape of a general incandescent bulb, but can be applied to lamps with a cap having various other external shapes and uses. In addition, although it is applied to a small lamp with a cap that can replace the E17-cap mini-krypton bulb 60W, the present invention is not limited to this, but can be replaced with an incandescent bulb such as an E26 cap 40W, 60W, 100W, or a bulb-type fluorescent lamp. It may be applied to a lamp with a base.

  The main body made of the heat conductive member is made of aluminum, but may be a metal such as an alloy containing aluminum as a main component. Further, in order to improve the heat dissipation of the solid state light emitting device, the metal has good heat conductivity. For example, you may form with the metal containing at least 1 type of aluminum (Al), copper (Cu), iron (Fe), and nickel (Ni). In addition, you may comprise industrial materials, such as aluminum nitride (AlN) and silicon carbide (SiC). Furthermore, you may comprise with synthetic resins, such as high heat conductive resin. Appearance shape is formed in a shape that approximates the silhouette of the neck part of a general incandescent bulb so that the diameter gradually decreases from one end to the other, improving the application rate to existing lighting fixtures. In this case, it is not a condition to approximate a general incandescent lamp, and the shape is not limited to a specific shape. In addition, in order to further improve the heat dissipation performance, a large number of heat radiation fins, heat radiation pins, and the like that project radially from one end to the other end may be integrally formed on the outer peripheral surface of the main body.

  The solid state light emitting element is preferably composed of, for example, an LED chip made of a gallium nitride (GaN) -based semiconductor that emits blue light. However, a solid state light emitting element using a semiconductor laser, an organic EL, or the like as a light source is acceptable. The Moreover, although it was made to light-emit in white, according to the use of a lighting fixture, you may comprise red, blue, green, etc., and also combining various colors. Further, it may have a light control or color adjustment function.

  The light emitting unit is mounted with a solid light emitting element partially or entirely arranged in a regular order such as a matrix shape, a staggered shape, or a radial shape using COB (Chip on Board) technology on one side of the substrate. It may be configured as a COB module or a SMD (Surface Mount Device) package. In the case of the SMD package, the light emitting unit may be configured by a plurality of solid state light emitting devices. Preferably, the necessary number is selected according to the use of lighting. For example, about four element groups may be formed, and one group or a plurality of groups may be formed. Furthermore, it may be composed of a single solid state light emitting device.

  As described above, the light emitting unit is preferably configured as a light emitting module configured by mounting a solid light emitting element serving as a light source on the surface of the substrate, but may be a light emitting unit configured without a substrate. . Further, the shape of the light-emitting portion may be a plate-like circle, a rectangle, a polygon such as a hexagon, or an ellipse to form a point or surface module, and a desired light distribution. All shapes for obtaining properties are acceptable.

  For example, the light emitting unit is arranged such that the other surface side of the metal substrate on which the solid light emitting element is disposed on one surface side can conduct heat to the substrate support unit formed on one end side of the main body. It is preferable to dissipate heat generated mainly from the back surface side of the solid state light emitting device through the main body. However, the substrate support portion may be configured to have a flat wide area or a ring shape. Specific means for dissipating heat through the main body may be as described above, such as a stepped support portion, and the substrate material is not limited to metal but may be synthetic resin such as glass epoxy. The configuration is not limited to the exemplified configuration. In addition, the light emitting unit may radiate heat generated from the solid light emitting element only through the main body, or may radiate heat through the main body and another member, for example, a base member.

  In addition, the cover member is a bulb having a G-shaped spherical shape, such as an A-shaped or PS-shaped bulb having the same external shape as a bulb for a general lighting bulb such as an incandescent bulb, or a G-shaped spherical shape. It is suitable to be composed of globes of the same shape or substantially the same shape as the bulbs of T shape and R shape, but even in the shape of a dish that forms a flat thin structure lamp, Furthermore, you may comprise with the protective cover which makes the transparent or semi-transparent plate shape for protecting the charging part etc. of solid light emitting elements, such as a light emitting diode, from the outside.

  The cover member may be colorless and transparent, translucent with light diffusibility such as milky white according to the required characteristics, and may be colored, etc. Reflective film on a part of the globe etc. to improve the light distribution characteristics Or the like may be formed. In addition, the cover member preferably constitutes an envelope that substantially seals the light-emitting portion, but it is sufficient that the cover member is optically sealed rather than a condition that it is completely sealed. What formed the hole for ventilation etc. may be used.

  As the base member, all bases that can be attached to a socket to which a general incandescent bulb, a bulb-type fluorescent lamp, or the like can be attached are allowed, but generally the most popular types such as Edison type E17 and E26 are suitable. is there. In addition, even if the material is a metal base as a whole, the electrical connection part is made of a metal such as a copper plate, and the other part is a plastic base made of a synthetic resin. The cap may be a GX53 base used for a flat thin lamp, a base having a pin-shaped terminal used for a fluorescent lamp, or a base having an L-shaped terminal used for hook sealing, and is limited to a specific base. Not.

  The lighting device for lighting the solid state light emitting element is advantageous in that it can be replaced with a light source such as a general incandescent light bulb as it is, but can also be provided separately. Further, the lighting device may have a light control circuit, a color control circuit, and the like for dimming the solid state light emitting device.

  In this embodiment, the lighting fixture can be a ceiling-embedded type, a direct-attached type, a suspended type, or a wall-mounted type, and a glove, shade, reflector, etc. can be attached to the fixture body as a light control body. Even if it exists, the lamp | ramp with a nozzle | cap | die used as a light source may be exposed. Moreover, not only what attached the lamp | ramp with one nozzle | cap | die to the instrument main body, A plurality may be arrange | positioned. Furthermore, a large indoor / outdoor lighting apparatus for facilities / businesses such as an office may be configured.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and various design changes can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Illuminating device 11 Main body 13 Light emission part 14 Cover member 14-1 Hemisphere 14-2 Translucent member 18 Positioning means 19 Joining material 30 Lighting fixture 31 Appliance main body

Claims (4)

A body made of a thermally conductive member;
A light emitting unit disposed on the body;
It provided so as to cover the light emitting portion, a semi-sphere and made of a ceramic having a light-transmitting member to be joined of a translucent bonding material containing glass hemisphere translucent cover member;
An illumination device comprising: The lighting device according to claim 1, wherein the cover member has alignment means at a joint portion. It said cover member is a wall thickness of 0.5 to 3 mm, and the lighting according to claim 1 or 2 surface area ratio of the main body / the cover member and wherein 0.2 to 1.5 der Rukoto apparatus. An instrument body;
The lighting device according to any one of claims 1 to 3 , wherein the lighting device is mounted on an appliance body;
The lighting fixture characterized by comprising.

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