JP2011253698A - Lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lamp capable of improving a heat-radiating structure and aiming at downsizing of the lamp and improving an assembling workability.SOLUTION: A lamp envelope of the lamp is formed of a globe 2, a metal holder 3, and an outer case 5 arranged between the holder 3 and a base 4. An LED module 6 is covered with a hemishperical translucent globe 2. The outer case 5 is a case of a metallic cylindrical radiator wherein an anodized aluminum treatment is applied to the surface of the case. The holder 3 is made of a metal board where the LED module 6 is arranged, and a cylindrical section 3b extending to a base 4 side is arranged on an outer peripheral edge of the holder 3. The holder 3 is arranged by covering on an opening of the outer case 5. A caulked section 9 is formed by being caulked at an overlapped section of the holder 3 and the outer case 5, and the holder 3 and the outer case 5 are firmly fixed with the caulked section.

Description

  The present invention relates to a lamp using a semiconductor light emitting element.

  In recent years, semiconductor light emitting devices such as LED (Light Emitting Diode) have higher energy efficiency and longer life than incandescent bulbs and halogen bulbs. Therefore, as a new light source for lamps that can contribute to prevention of global warming through energy saving. Research and development of LED lamps using LED as a light source are underway.

  It is known that the light output of an LED decreases as its temperature rises and its life is shortened. For this reason, the LED lamp is required to have an efficient heat dissipation structure in order to suppress the temperature rise of the LED. Thus, various LED lamps having an efficient heat dissipation structure have been proposed (see, for example, Patent Document 1 and Patent Document 2).

  5 and 6 are sectional views of conventional LED lamps disclosed in Patent Document 1 and Patent Document 2. FIG. The conventional LED lamp 13 described in Patent Document 1 shown in FIG. 5 has a trumpet-shaped metal heat radiating portion 14 that is open at both ends, and the metal substrate 16 on which the LED element 15 is mounted at one end is heated. Those fixed through the conductive member 17 are known. Further, the conventional LED lamp 18 described in Patent Document 2 shown in FIG. 6 exposes the outer member 19 in which a metal holder 19a and an outer peripheral surface portion 19b functioning as a heat radiating surface are formed as an integrally molded product. The LED substrate 20 is disposed in the light source mounting portion of the metal holder 19a, and the recess 21 is formed inside the outer peripheral surface portion 19b. The lighting circuit 22 is housed inside the recess 21. One in which the insulating member 23 is provided in contact with the inner surface of the recess 21 is known.

Japanese Patent Laid-Open No. 2001-243809 JP 2009-267082 A

  In the example shown in FIG. 5, the metal substrate 16 on which the LED elements 15 are mounted is fixed to the trumpet-shaped metal heat radiating portion 14 via the high heat conductive member 17. Since the substrate 16 is provided, the heat dissipation structure is not sufficient. In addition, there is a problem that the number of components is increased, such as providing a high heat conduction member 17 between the metal heat radiating portion 14 and the metal substrate 16. Moreover, in the thing shown in FIG. 6, although the metal member 19a and the outer peripheral surface part 19b which functions as a heat radiating surface have the outer member 19 formed as an integral molded product exposed outside, Therefore, the metal outer member 19 is thick and heavy, and has a bottomed shape in which a concave portion 21 is formed inside the outer peripheral surface portion 19b of the outer member 19, and the lighting circuit 22 is provided inside the concave portion 21. Since the insulating member 23 is provided in contact with the inner surface of the recess 21, there is a problem in that it is difficult to insert and the assembly workability is not preferable in order to improve the adhesion.

  The present invention has been made to solve such problems, and provides a lamp capable of improving the heat dissipation structure, reducing the weight of the lamp, and further improving the assembly workability. .

  A lamp according to the present invention includes a light source made of a semiconductor light emitting element, a metal holder for arranging the light source, a lighting circuit for lighting the light source, an inner case for housing the lighting circuit, and the inner case. An outer case that has a space between the inner surface of the outer case and the outer surface of the inner case, and the one end opening of the outer case covers the one end opening of the outer case from the outside. The holder is provided, and the holder and the outer case are fixed at an overlapping portion between the holder and the outer case.

  Thereby, since the holder which has arrange | positioned the light source touches external air directly, heat dissipation improves. In addition, the thickness of the outer case can be reduced to reduce the weight, and the inner case can be stored in the outer case with a margin because the inner case and the outer case do not need to be closely attached. Can be improved. Further, the heat of the light source can be prevented from being transmitted to the circuit, the temperature rise of the lighting circuit can be suppressed, and the circuit life can be prevented from decreasing. Further, the heat from the light source can be released from the holder, and the heat of the lighting circuit can be released from the base through the inner case, thereby preventing the heat from flowing around and preventing the temperature of the lighting circuit from rising. Further, since there is a gap between the inner surface of the outer case and the outer surface of the inner case, it is avoided that the outer case is sealed by a space surrounded by the inner surface of the outer case and the outer surface of the inner case. By ensuring the convection, local high temperature is prevented. In addition, since there is a gap between the inner surface of the outer case and the outer surface of the inner case, the assembly workability is also improved.

  Further, the fixing may be caulking. Thus, the outer case and the metal holder can be easily fixed. In this case, the caulking may be performed by pressing a needle-like instrument or caulking with a ring-shaped jig.

  Further, a non-thermally conductive member may be interposed at the overlapping portion between the holder and the outer case. Thereby, the heat of the light source can be further prevented from being transmitted to the circuit, the temperature rise of the lighting circuit can be suppressed, and the circuit life can be prevented from decreasing.

  Moreover, you may have the ventilation port which connects the said external case inside and the said external case exterior in the overlap location of the said holder and the said external case. As a result, heat is released from the lamp holder 3, the outer case 5, the inner case 7, and the like through the gap 12 that serves as a vent hole, thereby suppressing a rise in the temperature of the lighting circuit and preventing a reduction in circuit life. it can.

  Thereby, since the holder which has arrange | positioned the light source touches external air directly, heat dissipation improves. In addition, the thickness of the outer case can be reduced to reduce the weight, and the inner case can be stored in the outer case with a margin because the inner case and the outer case do not need to be closely attached. Can be improved. Further, the heat of the light source can be prevented from being transmitted to the circuit, the temperature rise of the lighting circuit can be suppressed, and the circuit life can be prevented from decreasing. Further, the heat from the light source can be released from the holder, and the heat of the lighting circuit can be released from the base through the inner case, thereby preventing the heat from flowing around and preventing the temperature of the lighting circuit from rising. Further, since there is a gap between the inner surface of the outer case and the outer surface of the inner case, it is avoided that the outer case is sealed by a space surrounded by the inner surface of the outer case and the outer surface of the inner case. By ensuring the convection, local high temperature is prevented. In addition, since there is a gap between the inner surface of the outer case and the outer surface of the inner case, the assembly workability is also improved.

The front view of the lamp | ramp which concerns on one embodiment of this invention Same sectional view Similarly, a partially cutaway side view for explaining the overlapped portion avoiding the caulking portion Also enlarged cross-sectional side view Cross-sectional view of a conventional LED lamp Cross-sectional view of another conventional LED lamp

  Hereinafter, a lamp according to an embodiment of the present invention will be described in detail with reference to the drawings.

  A lamp 1 according to an embodiment of the present invention shown in FIG. 1, FIG. 2, FIG. 3 and FIG. 4 is a light bulb type LED lamp, and includes a globe 2, a disc-shaped metal holder 3, and a holder. A lamp envelope is constituted by the outer case 5 arranged between the cap 3 and the base 4.

  The globe 2 is a hemispherical translucent cover for radiating light emitted from the LED module 6 that is a light source made of a semiconductor light emitting element to the outside of the lamp. The LED module 6 is covered with the globe 2. The globe 2 is subjected to a light diffusion process such as a ground glass process in order to diffuse the light emitted from the LED module 6. The opening side of the globe 2 has a narrowed shape, and the opening end of the globe 2 is disposed in contact with the upper surface of the holder 3. Specifically, the opening end of the globe 2 is inserted into a circumferential groove 3a provided in the holder 3, and is fixed to the holder 3 with a heat-resistant silicone adhesive. The shape of the globe 2 is not limited to a hemispherical shape, and may be a spheroid or an oblate sphere. In the present embodiment, the material of the globe 2 is a glass material. However, the material of the globe 2 is not limited to a glass material, and the globe 2 may be molded from a synthetic resin or the like.

  The base 4 is a power receiving unit for receiving AC power through two contact points. The power received by the base 4 is input to the power input portion of the circuit board 8a of the lighting circuit 8 housed in a resin-made inner case 7 described later via a lead wire (not shown). The base 4 is a metallic bottomed cylindrical body that is E-shaped, and has an outer surface formed with a screwing portion 4b for screwing into a socket (not shown) of the lighting device. . Further, on the inner peripheral surface of the base 4, a screwing part 4 c for screwing with the protrusion 7 c of the base attaching part 7 b of the inner case 7 is formed.

  The outer case 5 is a case of a thin metal tubular radiator having a thickness of 0.3 to 0.4 mm having two openings in the vertical direction, and a first opening constituting an opening on the globe 2 side. Part 5a and a second opening 5b constituting an opening on the base 4 side. The diameter of the first opening 5a is larger than the diameter of the second opening 5b, and the outer case 5 is a cylindrical body having an inverted truncated cone shape as a whole. In the present embodiment, the outer case 5 is made of an aluminum alloy material. The surface of the outer case 5 is anodized to improve the thermal emissivity. Although the outer case 5 is made of metal, a resin outer case such as PET or PBT may be used.

  The LED module 6 is an example of a light source composed of a semiconductor light emitting element, and is a light emitting module (light emitting unit) that emits predetermined light. The LED module 6 includes a rectangular ceramic substrate 6a, a plurality of LED chips 6b mounted on one surface of the ceramic substrate 6a, and a sealing resin (not shown) for sealing the LED chip 6b. ing. Predetermined phosphor particles are dispersed in the sealing resin, and light emitted from the LED chip 6b is converted into a desired color by the phosphor particles.

  In the present embodiment, a blue LED that emits blue light is used as the LED chip 6b, and yellow phosphor particles are used as the phosphor particles. Thus, yellow light is emitted from the yellow phosphor particles by being excited by blue light from the blue LED, and white light is emitted from the LED module 6 by the combination of the yellow light and the blue light from the blue LED. The

  In the present embodiment, about 100 LED chips 6b are mounted on the ceramic substrate 6a in a matrix. The LED module 6 is provided with two electrodes connected to lead wires extending from the power output portion formed on the circuit board 8a. When the DC power is supplied to the LED module 6 from these two electrodes, the LED chip 6b emits light.

  The holder 3 is a light source mounting member (module plate) made of a metal substrate having a thickness of 3 to 6 mm for disposing the LED module 6, and is formed into a disk shape by aluminum die casting. Further, a cylindrical portion 3b having a thickness of 0.3 to 0.4 mm is provided at the periphery of the outer peripheral surface of the holder 3 so as to extend at a height of 4 to 7 mm toward the base 4 side. The holder 3 is a heat radiator that directly radiates heat generated from the LED module 6 to the outside of the lamp and transmits the heat to the outer case 5. The holder 3 is provided so as to cover the opening end of the outer case 5 on the first opening 5a side so as to cover from the outside. Caulking with a needle-shaped jig from the outside toward the lamp shaft at the overlapping portion of the holder 3 and the outer case 5, that is, the overlapping portion of the cylindrical portion 3b of the holder 3 and the first opening 5a of the outer case 5. A portion 9 is formed, and the holder 3 and the outer case 5 are fixed by the caulking portion 9. In the present embodiment, the height of this overlapping portion is 3 mm. The caulking portions 9 are formed by caulking at four locations at equal intervals in the outer peripheral surface of the cylindrical portion 3 b of the holder 3, that is, in the overlapping portion between the holder 3 and the outer case 5. Although four caulking portions 9 are provided, the number of the caulking portions 9 is preferably 4 to 8 in terms of appearance, and the holder 3 and the outer case 5 can be more firmly fixed if further increased. Moreover, the outer peripheral surface of the holder 3 is anodized in the same manner as the outer case 5 to improve the thermal emissivity.

  FIG. 3 shows a state in which the lamp of the present embodiment is rotated about the lamp axis by about 10 degrees. As is apparent from the drawing of the notch, the portion not caulked by the caulking portion is the outer case 5. A gap 12 of, for example, 0.01 to 0.1 mm is provided between the holder 3 and the cylindrical portion 3b, and the lamp 12 is interposed via the gap 12, that is, the gap 12 serving as a ventilation opening as shown by an arrow A in FIG. Heat is released from the inner holder 3, the outer case 5, the inner case 7, and the like.

  In addition, the holder 3 is formed with a recess 3c for placing the LED module 6 therein. In the present embodiment, the recess 3 c is formed in a rectangular shape having the same shape as the ceramic substrate 6 a of the LED module 6. The LED module 6 disposed in the recess 3c is sandwiched between the stoppers 6c.

  The inner case 7 is a resin-made cylinder that houses the lighting circuit 8 having the circuit element group 8 b, and is a circuit housing portion 7 a that is an inverted frustoconical cylindrical body substantially the same shape as the outer case 5, the base 4, and the like. It consists of a base attaching part 7b which is a substantially identical cylindrical body. The inner case 7 functions as an insulating case for preventing the circuit element group 8b from coming into contact with the metal outer case 5. A circuit accommodating portion 7 a of the inner case 7 is accommodated in the outer case 5, and a base attaching portion 7 b of the inner case 7 is provided so as to protrude from the second opening 5 b of the outer case 5. The gap between the outer case 5 and the inner case 7 is 1 mm to 3 mm in a wide area.

  In the present embodiment, the circuit housing portion 7a and the base attaching portion 7b constituting the inner case 7 are integrally injection-molded. The inner case 7 is molded from, for example, polybutylene terephthalate (PBT) containing 15 to 40% alumina having a particle size of 1 to 10 μm. In addition to the PBT, polyphenylene sulfide resin (PPS) containing 10 to 40% of zinc oxide (ZnO) having a particle size of 1 to 10 μm may be used as the material of the inner case 7. In short, it is preferable to use a high thermal conductive resin as the material of the inner case 7.

  A resin cap 10 is attached to the opening on the holder 3 side of the circuit housing portion 7a.

  The resin cap 10 has a substantially disk shape, and an annular protruding portion 10a protruding in the axial direction of the inner case 7 is formed at the outer peripheral end portion on the inner surface side. A plurality of locking claws (not shown) for locking the circuit board are formed on the inner peripheral surface of the protruding portion 10a. The outer peripheral surface of the protruding portion 10 a is configured to be fitted into the opening on the holder 3 side of the circuit housing portion 7 a of the inner case 7. The resin cap 10 can be molded using the same material as the inner case 7. The material of the resin cap 10 is also preferably a high thermal conductive resin. The resin cap 10 is formed with a through hole (not shown) for passing a lead wire for supplying power to the LED module 6.

  The lighting circuit 8 includes a circuit element group 8b constituting a circuit (power supply circuit) for causing the LED chip 6b of the LED module 6 to emit light, and a circuit board 8a on which each circuit element of the circuit element group 8b is mounted.

  The circuit element group 8 b includes a plurality of circuit elements for generating power for causing the light source (LED module 6) to emit light from the power received by the base 4, and the AC power received by the base 4. Is converted to DC power, and DC power is supplied to the LED chip 6 b of the LED module 6. The circuit element group 8b includes a first capacitor element 8c that is an electrolytic capacitor (vertical capacitor), a second capacitor element 8d that is a ceramic capacitor (horizontal capacitor), a resistor element 8e, and a voltage conversion element including a coil. 8f and a semiconductor element 8g which is an integrated circuit of IPD (intelligent power device). Among the circuit elements constituting the circuit element group 8b, circuit elements that particularly require heat dissipation measures are components that generate a large amount of heat, that is, a capacitor element (particularly the first capacitor element 8c) and a semiconductor element 8g that are capacitors.

  The circuit board 8a is a disk-shaped printed board, and a circuit element group 8b is mounted on one surface. As described above, the circuit board 8a is held on the resin cap 10 by the locking claws of the resin cap 10. The circuit board 8a is provided with a notch. This notch constitutes a path for passing lead wiring for supplying DC power to the LED module 6 from the surface side on which the circuit element group 8b is mounted to the opposite surface.

  The insulating ring 11 ensures insulation between the base 4 and the outer case 5, and is disposed between the base 4 and the outer case 5. The inner peripheral surface of the insulating ring 11 is in contact with the outer peripheral surface of the base attaching portion 7 b of the inner case 7. The insulating ring 11 is sandwiched between the opening end of the base 4 and the opening end of the outer case 5 by screwing the base mounting portion 7 b of the inner case 7 and the base 4. The insulating ring 11 is preferably formed from a high thermal conductive resin.

  In the present embodiment, with the above configuration, the heat dissipating property is improved because the holder in which the light source is disposed directly touches the outside air. For this reason, the thickness of the outer case can be reduced and the weight can be reduced. Further, since the inner case and the outer case do not need to be in close contact with each other, the inner case can be accommodated in the outer case with a margin, so that the assembling workability can be improved. Further, the heat of the light source can be prevented from being transmitted to the circuit, the temperature rise of the lighting circuit can be suppressed, and the circuit life can be prevented from decreasing. Further, the heat from the light source can be released from the holder, and the heat of the lighting circuit can be released from the base through the inner case, thereby preventing the heat from flowing around and preventing the temperature of the lighting circuit from rising. Further, since there is a gap between the inner surface of the outer case and the outer surface of the inner case, it is avoided that the outer case is sealed by a space surrounded by the inner surface of the outer case and the outer surface of the inner case. By securing the convection, local high temperature is prevented, and when the vent hole is formed at the overlapping portion, the heat in the lamp can be dissipated and the heat dissipation is improved.

  In the above embodiment, since the caulking is fixed, the outer case and the metal holder can be easily fixed. A method other than caulking, for example, fixing using an adhesive or a screw may be used. For the caulking, a needle-like instrument is used. However, the caulking may be caulked with a ring-like caulking jig over the entire circumference or at intervals. According to the ring caulking at intervals, a gap 12 as a vent hole is formed at a location that is not caulked, so that heat dissipation is improved.

  Further, a non-thermally conductive member, for example, a silicone resin, an epoxy, or the like may be interposed at the overlapping portion between the holder 3 and the outer case 5. Thereby, it is possible to further prevent the heat of the light source from being transmitted from the holder 3 to the lighting circuit through the outer case 5, to suppress the temperature increase of the lighting circuit, and to prevent the circuit life from being reduced.

  INDUSTRIAL APPLICABILITY The present invention is useful as an LED lamp using a semiconductor light emitting element such as an LED as a light source, and particularly as a small light bulb type LED lamp whose heat dissipation design is difficult due to its size and structure.

DESCRIPTION OF SYMBOLS 1 Lamp 2 Globe 3 Holder 4 Base 5 Outer case 6 LED module 7 Inner case 8 Lighting circuit 9 Caulking part 10 Resin cap 11 Insulation ring 12 Gap

Claims (4)

A light source comprising a semiconductor light emitting element, a metal holder for placing the light source, a lighting circuit for lighting the light source, an inner case for housing the lighting circuit, and an outer case for housing the inner case, There is a gap between the inner surface of the outer case and the outer surface of the inner case, and the one end opening of the outer case is provided with the holder covering the one end opening of the outer case from the outside, The lamp, wherein the holder and the outer case are fixed at an overlapping portion between the holder and the outer case. The lamp according to claim 1, wherein the fixing is caulking. The lamp according to claim 1 or 2, wherein a non-thermally conductive member is interposed at an overlapping portion between the holder and the outer case. The lamp according to any one of claims 1 to 3, further comprising a vent hole that communicates the inside of the outer case and the outside of the outer case at an overlapping portion between the holder and the outer case.

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