JP2017084534A - Luminaire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a luminaire which efficiently radiates heat generated by light emitting elements disposed on a substrate.SOLUTION: A luminaire includes: a substrate 11; light emitting elements 12 disposed on a first surface 11a of the substrate 11; and a shell housing 20 for holding the substrate 11. The substrate 11 is fixed to the shell housing 20 in a state that a second surface 11b opposite to the first surface 11a of the substrate 11 contacts with the shell housing 20.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a lighting device having a light emitting element such as a light emitting diode (LED).

  Semiconductor light emitting devices such as LEDs are used as light sources for various products because of their small size, high efficiency, and long life. For example, an illumination device (LED illumination) using an LED as a light source has been put into practical use.

  As LED lighting, known bulb-type fluorescent lamps, bulb-type LED lamps (LED bulbs) that replace incandescent bulbs, or straight tube LED lamps that substitute for straight-tube fluorescent lamps are known. It has been. In addition, lighting fixtures such as a ceiling light, a downlight, or a spotlight are also known as LED lighting.

  For example, a conventional LED bulb supports a light emitting module composed of a substrate and LED elements mounted on the substrate, a globe that covers the light emitting module, a base (module plate) for mounting the light emitting module, and a base And a base (see, for example, Patent Document 1). The LED bulb is lit by converting AC power received from the base into DC power by a circuit unit housed in the casing and supplying the DC power to the light emitting module.

Japanese Unexamined Patent Publication No. 2015-076281

  In the illuminating device, heat is generated by the light emitting element as a light source. Therefore, it is necessary to efficiently dissipate this heat. In particular, when a semiconductor light emitting element such as an LED is used as the light emitting element, the light emission efficiency is reduced due to the heat generated by the semiconductor light emitting element itself, and the light output is reduced. For this reason, it is important to efficiently dissipate the heat generated in the semiconductor light emitting device.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide an illumination device that can efficiently dissipate heat generated by a light emitting element disposed on a substrate.

  In order to achieve the above object, one aspect of a lighting device according to the present invention includes a substrate, a light emitting element disposed on a first surface of the substrate, and an outer casing that holds the substrate, The substrate is fixed to the outer casing such that a second surface opposite to the first surface of the substrate is in contact with the outer casing.

  ADVANTAGE OF THE INVENTION According to this invention, the heat which generate | occur | produces with the light emitting element arrange | positioned at a board | substrate can be thermally radiated efficiently.

1 is an external perspective view of an LED bulb according to Embodiment 1. FIG. 1 is an exploded perspective view of an LED bulb according to Embodiment 1. FIG. 1 is a cross-sectional perspective view of an LED bulb according to Embodiment 1. FIG. FIG. 3 is an enlarged cross-sectional view of a main part of the LED bulb according to Embodiment 1. FIG. 6 is an enlarged cross-sectional view of a main part of an LED bulb according to a modification of the first embodiment. FIG. 5 is a cross-sectional perspective view of an LED bulb according to Embodiment 2. FIG. 6 is a perspective view of an outer casing in an LED bulb according to Embodiment 2. It is a principal part expanded sectional view of the LED bulb which concerns on Embodiment 2. FIG. It is a principal part expanded sectional view of the LED bulb which concerns on the modification of Embodiment 2. FIG.

(Embodiment)
Embodiments of the present invention will be described below. Note that each of the embodiments described below shows a preferred specific example of the present invention. Therefore, numerical values, shapes, materials, components, arrangement positions and connection forms of components, and steps and order of steps shown in the following embodiments are merely examples and are not intended to limit the present invention. Absent. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims showing the highest concept of the present invention are described as optional constituent elements.

  Each figure is a mimetic diagram and is not necessarily illustrated strictly. In each figure, the same numerals are given to the composition which has the substantially same function, and the overlapping explanation is omitted or simplified.

  In the following embodiments, an LED bulb as an alternative to a bulb-type fluorescent lamp or an incandescent bulb will be described as an example of a lighting device.

(Embodiment 1)
[LED bulb]
An overall configuration of the LED bulb 1 according to Embodiment 1 will be described with reference to FIGS. 1, 2, and 3. FIG. 1 is an external perspective view of an LED bulb 1 according to Embodiment 1. FIG. FIG. 2 is an exploded perspective view of the LED bulb 1. FIG. 3 is a cross-sectional perspective view of the LED bulb 1 taken along line III-III in FIG.

  As shown in FIGS. 1 to 3, the LED bulb 1 includes an LED module 10, an outer casing 20 that holds the LED module 10, a globe 30 that covers the LED module 10, and a circuit for causing the LED module 10 to emit light. A unit 40 and a base 50 are provided. As shown in FIG. 1, the LED bulb 1 includes an outer casing 20, a globe 30, and a base 50, which form an envelope.

  Hereinafter, the detailed configuration of the LED bulb 1 will be described with reference to FIGS. 1 to 3 and FIG. 4. 4 is an enlarged cross-sectional view of a main part of the LED bulb 1 according to Embodiment 1, and shows the structure of the region X surrounded by the broken line in FIG.

[LED module]
The LED module 10 is an example of a light emitting module that emits light of a predetermined color, and emits white light, for example. As shown in FIG. 3, the LED module 10 is disposed inside the globe 30 and emits light by the electric power supplied from the circuit unit 40.

  The LED module 10 is fixed to the outer casing 20. Specifically, the LED module 10 is fixed to the opening 21 of the outer casing 20 so as to cover the opening 21 of the outer casing 20.

  As illustrated in FIGS. 2 and 3, the LED module 10 includes a substrate 11 and a light emitting element 12 disposed on the substrate 11.

  The substrate 11 is a mounting substrate for mounting the light emitting element 12, and as shown in FIGS. 3 and 4, a first surface (front surface) 11 a and a first surface 11 a on which the light emitting element 12 is mounted. Has a second surface (back surface) 11b on the opposite side. The substrate 11 is, for example, a substantially circular plate-like substrate as a whole in plan view, but the shape of the substrate 11 is not limited to this, and may be a polygonal shape such as a rectangular shape. Moreover, although the thickness of the board | substrate 11 is 0.5 mm-5 mm, for example, it is not specifically limited. As shown in FIG. 2, an orientation flat is formed on the substrate 11.

  As shown in FIG. 4, the substrate 11 is fixed to the outer casing 20 with the second surface 11 b in contact with the outer casing 20. Specifically, the substrate 11 is in contact with the outer casing 20 by being placed on a mounting surface 21 a 1 provided in the opening 21 so as to cover the opening 21 of the outer casing 20. That is, the substrate 11 is supported by the placement portion 21 a of the outer casing 20.

  The substrate 11 is provided with a through hole 11c. A screw 60 for fixing the substrate 11 and the outer casing 20 is inserted through the through hole 11c. In the present embodiment, since the substrate 11 and the outer casing 20 are fixed by the two screws 60, the substrate 11 is provided with two through holes 11c.

  Examples of the substrate 11 include a metal base substrate obtained by applying an insulating film to a base material made of a metal material such as aluminum or copper, a ceramic substrate that is a sintered body of a ceramic material such as alumina, or a resin material. A resin substrate or the like is used. From the viewpoint of radiating heat generated in the light emitting element 12, a metal base substrate having the highest thermal conductivity among these may be used. The substrate 11 is a rigid substrate, but may be a flexible substrate.

  As shown in FIGS. 2 and 3, a connector terminal 13 is provided as a power feeding unit at the center of the first surface 11 a of the substrate 11. A part of the connector terminal 13 penetrates the substrate 11 and is connected to the circuit unit 40 on the second surface 11b side. Although not shown, metal wiring (not shown) for electrically connecting the connector terminal 13 and the light emitting element 12 is formed on the first surface 11 a of the substrate 11.

  The light emitting element 12 is disposed on the first surface 11 a of the substrate 11. In the present embodiment, the plurality of light emitting elements 12 are mounted on the substrate 11 so as to form an annular array. In the present embodiment, six light emitting elements 12 are mounted, but the number of mounted light emitting elements 12 is not limited to this, and may be one.

  The light emitting element 12 in the present embodiment is an individually packaged surface mount device (SMD) type LED element. As shown in FIG. 3, a container (package) 12a and a container 12a The LED chip 12b that is primarily mounted and a sealing member 12c that seals the LED chip 12b are included. The light emitting element 12 which is an SMD type LED element is secondarily mounted on the substrate 11.

  The container 12a is a resin molded product made of white resin or a white ceramic molded product, and has an inverted frustoconical concave portion (cavity). The inner surface of the recess is inclined and is configured to reflect light from the LED chip 12b upward.

  The LED chip 12b is mounted on the bottom surface of the recess of the container 12a. The LED chip 12b is an example of a semiconductor light emitting element that emits light with a predetermined direct-current power, and is a bare chip that emits monochromatic visible light. The LED chip 12b is, for example, a blue LED chip that emits blue light when energized.

  The sealing member 12c is a light-transmitting insulating resin material such as silicone resin. The sealing member 12c in the present embodiment includes a phosphor as a wavelength conversion material that converts the wavelength of light from the LED chip 12b. That is, the sealing member 12c is a phosphor-containing resin in which a phosphor is contained in a translucent resin, and wavelength-converts (color converts) light from the LED chip 12b to a predetermined wavelength. The sealing member 12c is filled in the recess of the container 12a.

  As the sealing member 12c, for example, when the LED chip 12b is a blue LED chip, a phosphor containing YAG (yttrium, aluminum, garnet) -based yellow phosphor particles dispersed in a silicone resin in order to obtain white light Resin can be used. As a result, the yellow phosphor particles are excited by the blue light of the blue LED chip to emit yellow light. Therefore, the sealing member 12c generates the yellow light from the yellow phosphor particles and the blue light from the blue LED chip. White light is emitted as combined light. It should be noted that a light diffusing material such as silica and a filler may be dispersed in the sealing member 12c.

  The plurality of light emitting elements 12 configured in this way are connected in series, for example, and emit light by DC power supplied from the circuit unit 40 via the connector terminal 13. Note that the connection mode of the plurality of light emitting elements 12 (series connection, parallel connection, combination connection of series connection and parallel connection, etc.) is not particularly limited.

[Outer casing]
As shown in FIGS. 2 and 3, the outer casing 20 includes an opening 21 (first opening) provided on the globe 30 side and an opening 22 (second opening) provided on the base 50 side. It is a cylindrical cylinder which has. The outer diameter of the opening 21 is larger than the outer diameter of the opening 22, and the cylindrical body constituting the outer casing 20 has a substantially cylindrical shape in which the outer diameter gradually changes. The outer casing 20 constitutes an outer member of the LED bulb 1, and the outer surface of the outer casing 20 is exposed to the outside (in the atmosphere). The outer casing 20 is disposed between the globe 30 and the base 50.

  The outer casing 20 functions as a support member for supporting the LED module 10. The LED module 10 is fixed to the outer casing 20 and supported by the outer casing 20.

  Specifically, as illustrated in FIG. 4, the opening portion 21 of the outer casing 20 is provided with a placement portion 21 a having a placement surface 21 a 1 for placing the substrate 11 of the LED module 10. . The second surface 11b of the substrate 11 is in surface contact with the placement surface 21a1.

  In the present embodiment, the mounting surface 21 a 1 has an annular plane that constitutes the end surface of the opening 21. That is, a part of the placement surface 21a1 is an annular flat surface that constitutes the end surface of the opening 21, and is, for example, an annular flat surface. Thus, since the mounting surface 21a1 has an annular flat surface, only the outer peripheral region of the substrate 11 comes into contact with the outer casing 20 (the mounting portion 21a). Note that the central region of the second surface 11 b of the substrate 11 faces the opening of the opening 21, and the central region of the substrate 11 is not in contact with the outer casing 20.

  As shown in FIGS. 2 to 4, the outer casing 20 has ribs 23 extending from the opening 21 of the outer casing 20 toward the back side (the base 50 side) along the inner surface of the outer casing 20. . That is, the rib 23 is a protrusion that protrudes inward from the inner surface of the outer casing 20 and extends from the opening 21 of the outer casing 20 toward the opening 22.

  In the present embodiment, one end surface (end surface on the globe 30 side) of the rib 23 constitutes a part of the placement surface 21a1 of the placement portion 21a. That is, one end portion of the rib 23 and the mounting portion 21 a are flush with each other, and the second surface 11 b of the substrate 11 is in surface contact with one end surface of the rib 23.

  A plurality of ribs 23 are provided along the circumferential direction of the inner surface of the outer casing 20. As shown in FIG. 2, in the present embodiment, two ribs 23 are provided. The two ribs 23 are provided at opposing positions. That is, the two ribs 23 are provided at intervals of 180 ° along the circumferential direction of the inner surface of the outer casing 20.

  Each of the two ribs 23 is provided with a screw hole 23a extending in the cylinder axis direction of the outer casing 20. As shown in FIGS. 3 and 4, a screw 60 through which the through hole 11c of the substrate 11 is inserted is screwed into the screw hole 23a. Therefore, the axial direction of the screw hole 23a coincides with the axial direction of the through hole 11c. The substrate 11 and the outer casing 20 are fixed by screwing the screws 60 inserted through the through holes 11 c into the screw holes 23 a of the ribs 23. Thus, the LED module 10 is held by the outer casing 20 by fixing the substrate 11 and the outer casing 20 by the screws 60. The screw 60 is, for example, a metal screw.

  The screw 60 screwed into the screw hole 23a of the rib 23 is located outside the light emitting element 12 when viewed from above (when viewed from the normal direction of the first surface 11a of the substrate 11). Specifically, the through hole 11 c of the substrate 11 is provided in the outer peripheral region of the substrate 11, and the screw 60 is attached so as to press the outer peripheral region of the substrate 11. That is, the screw 60 is present at a position close to the outer wall constituting the cylindrical body of the outer casing 20.

  As shown in FIG. 4, a gap is provided between the shaft portion of the screw 60 and the through hole 11 c of the substrate 11. In the present embodiment, the inner diameter of the through hole 11 c is larger than the inner diameter of the screw hole 23 a of the rib 23.

  In addition, an annular groove 21b is formed in the opening 21 on the outer side of the mounting portion 21a. An end of the opening 31 of the globe 30 is disposed in the groove 21b. The globe 30 and the outer casing 20 are fixed by an adhesive 24 filled in the groove 21b. As the adhesive 24 filling the groove 21b, for example, an adhesive made of silicone resin is used.

  In the present embodiment, the groove 21 b is formed up to a position facing the second surface 11 b of the substrate 11. That is, the groove portion 21b is formed to the back side of the substrate 11, and the outer peripheral end portion of the substrate 11 is in a state of protruding into the concave portion of the groove portion 21b. Thereby, the adhesive 24 filled in the groove 21b can be present up to the portion of the second surface 11b of the substrate 11 (back side of the substrate 11).

  A screwing portion for mounting the base 50 is formed on the outer surface of the opening 22 (the opening on the base 50 side). A base 50 is screwed into the opening 22.

  The outer casing 20 is thermally coupled to the LED module 10 in the opening 21 and functions as a heat radiating member (heat sink) that radiates heat generated in the LED module 10. Therefore, the outer casing 20 may be made of a material having high thermal conductivity such as a metal material or a high thermal conductive resin material in order to efficiently dissipate heat generated in the LED module 10 (light emitting element 12). . For example, the outer casing 20 may be made of a material having higher thermal conductivity than the substrate 11. In the present embodiment, the outer casing 20 is made of resin, and is made of an insulating resin material such as polybutylene terephthalate (PBT). The outer casing 20 is an integrally molded product.

  As shown in FIG. 3, a circuit unit 40 is disposed inside the outer casing 20. Therefore, the outer casing 20 can also dissipate heat generated by the circuit unit 40. In the present embodiment, the outer casing 20 directly surrounds the circuit unit 40. That is, the outer casing 20 functions as a circuit case (insulating case) that protects the circuit unit 40 from insulation.

  The outer casing 20 also functions as a holder that holds the circuit unit 40. Specifically, as shown in FIG. 3, a convex portion 25 having a slit is formed on the inner surface of the opening 22 of the outer casing 20 as a structure for fixing the circuit board 41. The circuit unit 40 is held by the outer casing 20 by being locked to the convex portion 25 with the circuit board 41 sandwiched between the slits.

[Glove]
As shown in FIGS. 3 and 4, the globe 30 is an example of a translucent cover that covers the light emitting element 12. In the present embodiment, the globe 30 is configured to cover the entire LED module 10. That is, the globe 30 covers the substrate 11.

  The globe 30 is configured to extract light emitted from the LED module 10 (light emitting element 12) to the outside of the lamp. That is, the light of the LED module 10 that has entered the inner surface of the globe 30 passes through the globe 30 and is extracted to the outside of the globe 30.

  The globe 30 is a hollow member having an opening 31 and has a substantially hemispherical shape with the top on the opposite side of the opening 31 closed. The globe 30 is, for example, a hollow rotating body and has a shape in which the opening 31 is narrowed.

  The globe 30 is fixed to the opening 21 of the outer casing 20. In the present embodiment, the end of the opening 31 of the globe 30 is disposed in the groove 21b provided in the opening 21 of the outer casing 20, and the glove 30 is filled with the adhesive 24 in the groove 21b. And the outer casing 20 are fixed to each other.

  As a material of the globe 30, a light-transmitting material made of a glass material such as silica glass transparent to visible light, or a resin material such as acrylic (PMMA) or polycarbonate (PC) can be used. In the present embodiment, the globe 30 is formed using a glass material having a higher thermal conductivity than the resin material.

  The globe 30 may be subjected to a diffusion process for diffusing the light emitted from the LED module 10. For example, the light diffusion function can be imparted to the globe 30 by forming a light diffusion film (light diffusion layer) on the inner surface or outer surface of the globe 30.

  Specifically, a milky white light diffusion film can be formed by applying a resin containing a light diffusing material such as silica or calcium carbonate, a white pigment, or the like to the entire inner surface or outer surface of the globe 30. Alternatively, the globe 30 can have a light diffusion function by forming a plurality of light diffusion dots or a plurality of minute depressions on the globe 30. Thus, by providing the globe 30 with the light diffusion function, the light incident on the globe 30 from the LED module 10 can be diffused, so that the light distribution angle can be widened. In addition, since the light of the LED has strong directivity, when the LED is used as the light source of the light emitting element 12, a crushing feeling (brightness unevenness) is generated by the plurality of light emitting elements 12 (LED elements). By providing the above, the crushing feeling caused by the plurality of light emitting elements 12 can be suppressed.

  In addition, you may make the globe 30 transparent so that the LED module 10 inside can be visually recognized without giving the light diffusion function to the globe 30. In addition, the shape of the globe 30 may be a spheroid or oblate sphere, or may be a shape that conforms to an A-type bulb that is a general bulb shape.

[Circuit unit]
The circuit unit 40 shown in FIGS. 2 and 3 is a drive circuit for causing the LED module 10 (light emitting element 12) to emit light. That is, the circuit unit 40 supplies power for causing the LED module 10 to emit light to the LED module 10. In the present embodiment, the circuit unit 40 is a lighting circuit for turning on and off the LED module 10 and constitutes a power supply unit (power supply circuit). For example, the circuit unit 40 converts AC power supplied from the base 50 into DC power, and supplies the DC power to the LED module 10. The LED module 10 (light emitting element 12) is turned on or off by DC power supplied from the circuit unit 40 (lighting circuit).

  The circuit unit 40 includes a circuit board 41 and a plurality of electronic components 42 mounted on the circuit board 41. The circuit unit 40 is disposed between the LED module 10 and the base 50. Specifically, the circuit unit 40 is accommodated in the outer casing 20. In the present embodiment, the circuit unit 40 is accommodated only by the outer casing 20. As shown in FIG. 3, the circuit unit 40 is held by the outer casing 20 by slidingly inserting the circuit board 41 into the slit of the convex portion 25 provided in the outer casing 20 and locking the circuit board 41 to the convex portion 25. ing. The fixing means for the circuit board 41 is not limited to this, and the circuit board 41 may be fixed to the outer casing 20 with screws or the like.

  The circuit board 41 is a printed circuit board (PCB) in which a metal wiring such as a copper foil is formed on one surface (solder surface). The plurality of electronic components 42 mounted on the circuit board 41 are electrically connected to each other by metal wiring formed on the circuit board 41.

  The circuit board 41 is provided with an output terminal 43 and an input terminal (not shown). The output terminal 43 is mechanically and electrically connected to the connector terminal 13 provided on the substrate 11 of the LED module 10. On the other hand, a pair of lead wires (not shown) are connected to the input terminal. The other end of the pair of lead wires connected to the input terminal is connected to the base 50.

  For example, the circuit board 41 is arranged in a posture (vertically placed) substantially parallel to the cylinder axis of the outer casing 20. Note that the circuit board 41 is not limited to the vertical arrangement, and the main surface of the circuit board 41 may be arranged in a posture (horizontal arrangement) substantially perpendicular to the cylinder axis of the outer casing 20. Further, the metal wiring formed on the circuit board 41 may be formed on both surfaces of the circuit board 41 instead of being formed only on one surface (one surface) of the circuit board 41. That is, the circuit board 41 may be a double-sided wiring board.

  The electronic component 42 mounted on the circuit board 41 is a plurality of circuit elements for lighting the LED module 10, for example, a capacitive element such as an electrolytic capacitor or a ceramic capacitor, a resistive element such as a resistor, a rectifier circuit element, A coil element, a choke coil (choke transformer), a noise filter, a semiconductor element such as a diode or an integrated circuit element, or the like.

  The circuit unit 40 configured as described above is insulated by being housed in the outer casing 20 made of an insulating resin material. In addition, in order to control the light emission state of the LED module 10, the circuit unit 40 may be combined with a light control circuit such as a light control circuit or a color control circuit, or a wireless communication circuit.

[Base]
A base 50 shown in FIGS. 2 and 3 is a power receiving unit that receives power for causing the LED module 10 (light emitting element 12) to emit light from the outside of the lamp. The base 50 is attached to a portion of the outer casing 20 opposite to the opening 21. Specifically, the base 50 is attached to the opening 22 of the outer casing 20.

  On the inner peripheral surface of the base 50, a screwing portion for screwing with a screwing portion formed in the opening 22 of the outer casing 20 is formed. The base 50 is externally fitted to the outer casing 20 by being screwed into the screwed portion of the opening 22.

  The LED bulb 1 is attached to the fixture body by mounting the base 50 fitted on the outer casing 20 to, for example, a socket of the fixture body of the lighting fixture. Specifically, on the outer peripheral surface of the base 50, a screwing portion for screwing into the socket of the instrument body is formed. By attaching the base 50 to the socket of the instrument main body, the base 50 can receive power from the instrument main body. The base 50 is supplied with AC power from a commercial power source, for example. The base 50 in the present embodiment receives AC power through two contact points, and the power received by the base 50 is input to the input terminal of the circuit unit 40 via a pair of lead wires.

  The base 50 has, for example, a bottomed cylindrical shape made of metal, and as shown in FIG. 3, a shell portion 51 whose outer peripheral surface is a threaded portion, and a shell portion 51 that is attached via an insulating portion 52. The eyelet part 53 is made. The insulating part 52 is made of, for example, glass cullet. One of the pair of lead wires connected to the circuit unit 40 is connected to the shell part 51 of the base 50, and the other is connected to the eyelet part 53 of the base 50.

  The type of the base 50 is not particularly limited, but in this embodiment, a screwed-type Edison type (E type) base is used. For example, as the base 50, E26 type, E17 type, E16 type or the like can be mentioned. Moreover, the nozzle | cap | die 50 may not be an Edison type but a swan type (insertion type).

[Effects]
Next, the structure and operation effects that are characteristic of the LED bulb 1 in the present embodiment will be described.

  As shown in FIG. 4, the LED bulb 1 includes a substrate 11, a light emitting element 12 disposed on the first surface 11 a of the substrate 11, and an outer casing 20 that holds the substrate 11. Is fixed to the outer casing 20 with the second surface 11 b in contact with the outer casing 20.

  That is, in the conventional LED bulb, the base (module plate) is arranged between the substrate 11 and the outer casing 20, but in the LED bulb 1 in the present embodiment, the base that has been conventionally used is replaced. The substrate 11 is directly connected to the outer casing 20 without being used.

  Thus, since the LED bulb 1 in the present embodiment does not use a base (module plate), the thermal resistance from the substrate 11 to the outer casing 20 is higher than that of a conventional LED bulb using a base. Can be reduced. Thereby, the heat generated in the light emitting element 12 is directly conducted from the substrate 11 to the outer casing 20 and is guided from the outer casing 20 to the outside (in the atmosphere). Therefore, the heat generated in the light emitting element 12 can be radiated efficiently. As a result, the highly efficient LED bulb 1 can be realized and the wattage can be easily increased.

  Moreover, by not using the base (module plate), the number of parts can be reduced as compared with the conventional LED bulb. Therefore, according to the LED bulb 1 in the present embodiment, it is possible to reduce the component cost and the number of assembly steps.

  Further, in the present embodiment, the outer casing 20 is a cylindrical tube having an opening 21, and the opening 21 has a mounting portion having a mounting surface 21 a 1 for mounting the substrate 11. 21a is provided. The substrate 11 is in contact with the outer casing 20 by being placed on the placement surface 21 a 1 so as to cover the opening 21.

  As a result, the substrate 11 can be brought into surface contact with the placement surface 21a1 of the placement portion 21a, so that the heat of the light emitting element 12 conducted to the substrate 11 can be efficiently conducted to the outer casing 20. Therefore, the heat generated in the light emitting element 12 can be dissipated more efficiently.

  In the present embodiment, the placement surface 21 a 1 of the placement portion 21 a has an annular flat surface that constitutes the end surface of the opening 21 of the outer casing 20.

  As a result, the substrate 11 comes into contact with the outer casing 20 (the mounting portion 21a) in the outer peripheral region of the substrate 11. That is, the substrate 11 and the outer casing 20 are in annular contact. In the present embodiment, the contact surface between the substrate 11 and the outer casing 20 has an annular shape. As described above, since the substrate 11 and the outer casing 20 are in contact with each other in an annular shape, the heat generated in the light emitting element 12 is uniformly dispersed and conducted in the circumferential direction of the substrate 11. Can be dissipated more efficiently.

  In the present embodiment, the outer casing 20 has ribs 23 extending from the opening 21 of the outer casing 20 toward the back side (the base 50 side) along the inner surface of the outer casing 20. In addition, one end surface of the rib 23 constitutes a part of the placement surface 21a1 of the placement portion 21a.

  As a result, the contact area between the substrate 11 and the outer casing 20 can be increased by the amount of the ribs 23 provided, so that the heat generated in the light emitting element 12 can be dissipated more efficiently.

  Note that a plurality of ribs 23 of the outer casing 20 may be provided along the circumferential direction of the inner surface of the outer casing 20.

  Thereby, since the contact area with the outer casing 20 can be further increased, the heat generated in the light emitting element 12 can be radiated more efficiently. At this time, the heat dissipation can be further improved by increasing the height (thickness) of the rib 23. Thereby, a higher watt LED bulb 1 can be realized.

  In the present embodiment, the rib 23 is provided with a screw hole 23 a extending in the cylinder axis direction of the outer casing 20, and the substrate 11 is provided with a through hole 11 c. And the board | substrate 11 and the outer housing | casing 20 are being fixed by the screw 60 penetrated by the through-hole 11c and screwed in the screw hole 23a.

  Thereby, the board | substrate 11 and the outer housing | casing 20 can be fixed using the rib 23. FIG. Furthermore, since the metal screw 60 has a higher thermal conductivity than the resin outer casing 20, the screw 60 functions as a heat conduction path by using the screw 60. Therefore, the heat generated in the light emitting element 12 can be dissipated more efficiently.

  In the present embodiment, the screw 60 is located outside the light emitting element 12 in a top view.

  As described above, by disposing the screw 60 functioning as a heat conduction path outside the light emitting element 12, the heat generated in the light emitting element 12 is easily guided to the outside. Therefore, the heat generated in the light emitting element 12 can be dissipated more efficiently.

  In the present embodiment, a gap is provided between the shaft portion of the screw 60 and the through hole 11 c of the substrate 11.

  Thereby, the stress generated when the screw 60 is tightened can be absorbed and relaxed in this gap.

  In the present embodiment, the LED bulb 1 includes a globe 30 that covers the light emitting element 12.

  Thereby, since the light emitting element 12 can be protected, the LED bulb 1 excellent in reliability can be realized.

  In this case, the globe 30 is preferably made of glass rather than resin.

  Thereby, the thermal conductivity of the globe 30 can be made larger than that made of resin. Therefore, the heat generated in the light emitting element 12 can be dissipated more efficiently. Actually, when the junction temperature (Ts) of the light emitting element 12 was measured, when the glass globe 30 was used, the junction temperature could be reduced by about 9 ° C. than when the resin globe 30 was used.

  Further, in the present embodiment, the opening 21 of the outer casing 20 is formed with an annular groove 21b on the outer side of the mounting portion 21a, and the end of the opening 31 of the globe 30 is the groove 21b. Is arranged.

  Thereby, since the glove | globe 30 can be positioned easily, the glove | globe 30 can be fixed to the outer housing | casing 20 with sufficient precision.

  In the present embodiment, the globe 30 and the outer casing 20 are fixed to each other with an adhesive 24 filled in the groove 21 b of the opening 21 of the outer casing 20.

  Thereby, since the globe 30 and the outer casing 20 can be fixed without any gap by the adhesive 24, it is possible to prevent insects, moisture, and the like from entering the globe 30.

  In the present embodiment, the groove 21b is formed up to a position facing the second surface 11b of the substrate 11.

  Thereby, the adhesive 24 can be filled up to the second surface 11b side (back side) of the substrate 11. As a result, since the cured adhesive 24 is caught on the outer peripheral end of the substrate 11, it is possible to suppress the globe 30 from falling out of the outer casing 20 together with the adhesive 24.

  In the present embodiment, the LED bulb 1 further includes a circuit unit 40 for causing the light emitting element 12 to emit light, and the circuit unit 40 is accommodated in the outer casing 20.

  Thus, by storing the circuit unit 40 in the outer casing 20, the LED bulb 1 incorporating the circuit unit 40 can be realized.

  In the present embodiment, the circuit unit 40 is accommodated only by the outer casing 20.

  Thereby, the circuit unit 40 can be protected by the outer casing 20. That is, the outer casing 20 can be used not only as an outer case of the LED bulb 1 but also as a circuit case. Therefore, the number of parts can be reduced. In this case, in order to ensure the dielectric strength of the circuit unit 40, the outer casing 20 may be made of an insulating material.

  In the present embodiment, the LED bulb 1 further includes a base 50 that receives power for causing the light emitting element 12 to emit light, and the base 50 is opposite to the opening 21 in the outer casing 20. It is attached to the part. Specifically, the base 50 is attached to the opening 22 of the outer casing 20.

  Thereby, the LED light bulb 1 which can be attached or detached to the socket of the fixture main body of a lighting fixture is realizable.

  In the present embodiment, the outer casing 20 is made of resin.

  Thereby, the LED bulb 1 excellent in safety can be manufactured at low cost.

(Modification of Embodiment 1)
FIG. 5 is an enlarged cross-sectional view of a main part of an LED bulb 1A according to a modification of the first embodiment.

  The LED bulb 1A in the present modification and the LED bulb 1 in the first embodiment differ in the relative positional relationship between the light emitting element 12 and the rib 23 provided in the outer casing 20. Regarding other configurations, the present modification and the first embodiment have the same configuration.

  Specifically, in the LED bulb 1 according to the first embodiment, the light emitting element 12 and the rib 23 do not overlap in the top view of the substrate 11. As shown in FIG. 3, the light emitting element 12 and the rib 23 overlap each other when the substrate 11 is viewed from above. That is, at least a part of the light emitting element 12 is opposed to the rib 23 of the outer casing 20 through the substrate 11, and the substrate 11 is sandwiched between the light emitting element 12 and the rib 23.

  For example, a part of the light emitting element 12 is located immediately above the rib 23 via the substrate 11. In other words, the rib 23 is located directly below a part of the light emitting element 12 with the substrate 11 interposed therebetween.

  In this way, by causing at least a part of the light emitting element 12 to face the rib 23 of the outer casing 20 via the substrate 11, the heat conduction path from the light emitting element 12 to the rib 23 can be shortened. Therefore, since the heat generated in the light emitting element 12 can be efficiently conducted to the outer casing 20, the heat generated in the light emitting element 12 can be radiated more efficiently.

  In addition, when making the light emitting element 12 and the rib 23 overlap, the rib 23 is good to be located just under the LED chip 12b which comprises the light emitting element 12. FIG. Thereby, since the heat conduction path from the LED chip 12b which is a heat source to the rib 23 can be further shortened, the heat generated in the light emitting element 12 can be dissipated more efficiently.

(Embodiment 2)
Next, the LED bulb 2 according to Embodiment 2 will be described with reference to FIGS. FIG. 6 is a cross-sectional perspective view of the LED bulb 2 according to the second embodiment. FIG. 7 is a perspective view of the outer casing 20 </ b> A in the LED bulb 2. FIG. 8 is an enlarged cross-sectional view of a main part of the LED light bulb 2 and shows a structure of a region Y surrounded by a broken line in FIG. In FIG. 6, the circuit unit 40 is omitted.

  The LED bulb 2 in the present embodiment and the LED bulb 1 in the first embodiment have different outer casing shapes. About the structure of those other than this, Embodiment 2 and Embodiment 1 are the same structures.

  Specifically, also in the present embodiment, as in the first embodiment, the outer casing 20 is provided with a plurality of ribs 23. However, in the first embodiment, the screw holes 23a are formed in all the two ribs 23, whereas in the present embodiment, the outer casing 20 is provided with ten ribs 23, Two of these ribs 23 are formed with screw holes 23a, but the remaining eight ribs 23 are not formed with screw holes 23a. That is, in the present embodiment, screw holes 23 a are formed only in at least some of the plurality of ribs 23.

  As for the rib 23 in which the screw hole 23a is not formed, like the rib 23 in which the screw hole 23a is formed, one end surface (end surface on the globe 30 side) constitutes a part of the mounting surface 21a1 of the mounting portion 21a. doing. That is, as shown in FIG. 8, the second surface 11b of the substrate 11 is in surface contact with one end surface of the rib 23 in which the screw hole 23a is not formed.

  Thus, in the present embodiment, the number of ribs 23 is increased with respect to the LED bulb 1 of the first embodiment. Thereby, the contact area of the board | substrate 11 and the outer housing | casing 20 can be increased by the amount which increased the number of the ribs 23. FIG. Therefore, the heat generated by the light emitting element 12 can be dissipated more efficiently than the LED bulb 1 of the first embodiment.

  Further, since the heat capacity of the outer casing 20 can be increased by increasing the number of ribs 23, the heat dissipation performance of the outer casing 20 can be improved. In addition, since the rib 23 extends in the direction from the opening 21 toward the opening 22, the heat of the light emitting element 12 conducted to the outer casing 20 is easily conducted to the base 50 side. As a result, the heat generated in the light emitting element 12 can be dissipated more efficiently.

  In addition, the rib 23 in which the screw hole 23a is not formed is provided with two or more along the circumferential direction of the inner surface of the outer housing | casing 20 similarly to the rib 23 in which the screw hole 23a was formed. Specifically, the ribs 23 in which the screw holes 23 a are not formed and the ribs 23 in which the screw holes 23 a are formed are provided at equal intervals along the circumferential direction of the inner surface of the outer casing 20. That is, all the ribs 23 are provided at radial positions so as to be equally spaced.

  Thereby, since the heat generated in the light emitting element 12 is conducted in the radial direction of the substrate 11, the heat generated in the light emitting element 12 can be dissipated more efficiently.

  Further, as shown in FIG. 9, also in this embodiment, the light emitting element 12 and the rib 23 are preferably overlapped when the substrate 11 is viewed from above. That is, at least a part of the light emitting element 12 is preferably opposed to the rib 23 of the outer casing 20 with the substrate 11 interposed therebetween. In this case, as shown in FIG. 9, the rib 23 facing the light emitting element 12 may not have the screw hole 23a formed therein, or may not have the screw hole 23a formed therein.

  In this way, by causing at least a part of the light emitting element 12 to face the rib 23 of the outer casing 20 via the substrate 11, the heat conduction path from the light emitting element 12 to the rib 23 can be shortened. Therefore, the heat generated in the light emitting element 12 can be dissipated more efficiently.

  In this case also, it is preferable that the ribs 23 exist immediately below the LED chip 12b constituting the light emitting element 12.

(Other variations)
The lighting device according to the present invention has been described above based on the embodiment and the modification. However, the present invention is not limited to the above-described embodiment and each modification.

  For example, in the first and second embodiments and the modifications described above, the substrate 11 and the outer casing 20 are fixed with two screws 60, but the substrate 11 and the outer casing 20 are fixed with three or more screws 60. It is better to fix. When the substrate 11 and the outer casing 20 are fixed with the two screws 60 as in the first and second embodiments, the substrate 11 (module substrate) warps due to the thermal stress caused by turning on and off the lighting device. Occurs. On the other hand, when the board | substrate 11 and the outer housing | casing 20 are fixed with the at least 3 screw 60, the curvature of the board | substrate 11 by the said thermal stress can be reduced. In addition, by fixing the substrate 11 and the outer casing 20 with the three or more screws 60, it is possible to suppress the occurrence of a gap between the substrate 11 and the outer casing 20, or even if a gap is formed. Therefore, the thermal conductivity from the substrate 11 to the outer casing 20 can be improved.

  In addition, the present invention can be realized not only as an LED bulb, but also as a lighting fixture including an LED bulb and a fixture main body to which the LED bulb is attached. The appliance body is provided with a socket to which a base of an LED bulb is attached. Moreover, the luminaire may include a translucent lamp cover that covers the LED bulb.

  Further, in the above-described first and second embodiments and modifications, the LED bulb has been described as an example. However, the present invention provides a straight tube LED lamp that replaces a straight tube fluorescent lamp, a GX53 base, a GH76p base, or the like. The present invention can also be applied to other LED lamps with caps such as flat LED lamps.

  In the first and second embodiments and the modifications described above, the lighting device with a base attached to the lighting fixture is described as an example of the lighting device. However, the lighting device according to the present invention is the lighting fixture itself. It can also be realized as. Examples of such a lighting device include a lighting device such as a downlight, a spotlight, a ceiling light, or a standlight installed on a ceiling or the like.

  In the first and second embodiments and the modifications described above, the substrate 11 and the outer casing 20 are fixed by the screws 60. However, the fixing method of the substrate 11 and the outer casing 20 is not limited to screwing. The substrate 11 and the outer casing 20 may be fixed by other fixing means such as an adhesive.

  Moreover, in said embodiment and modification, although the light emitting element 12 was mentioned as the SMD type LED element, it is not restricted to this. For example, a COB (Chip On Board) type LED module in which a bare chip is directly mounted (primary mounting) on a substrate may be used. That is, the LED chip itself may be employed as the light emitting element 12. In this case, the plurality of LED chips may be collectively or individually sealed with a sealing member. The sealing member may contain a wavelength conversion material such as a yellow phosphor as described above.

  In the first and second embodiments and the modifications described above, the light emitting element 12 is a BY type white LED element that emits white light by a blue LED chip and a yellow phosphor, but is not limited thereto. . For example, a phosphor-containing resin containing a red phosphor and a green phosphor may be used and combined with this and a blue LED chip to emit white light. In addition to the yellow phosphor, a red phosphor or a green phosphor may be further mixed for the purpose of improving color rendering. Alternatively, an LED chip that emits a color other than blue may be used, for example, an ultraviolet LED chip that emits ultraviolet light having a shorter wavelength than the blue light emitted by the blue LED chip, and is excited mainly by ultraviolet light. Alternatively, white light may be emitted by a blue phosphor, a green phosphor, and a red phosphor that emit blue light, red light, and green light.

  Moreover, in said Embodiment 1, 2 and a modification, the LED module 10 may be comprised so that light control and / or color control can be performed. For example, the LED module 10 includes a red LED light source that emits red light, a green LED light source that emits green light, and a blue LED light source that emits blue light, so that RGB control can be performed. Thereby, the LED module which can control toning is realizable.

  Further, in Embodiments 1 and 2 and the modifications described above, the LED is exemplified as the light source of the light emitting element 12. An element may be used.

  Other forms obtained by making various modifications conceived by those skilled in the art to the above-described embodiments and modifications, or constituent elements in the above-described embodiments and modifications without departing from the gist of the present invention The embodiment realized by arbitrarily combining the functions is also included in the present invention.

1, 1A, 2 LED bulb (lighting device)
DESCRIPTION OF SYMBOLS 11 Board | substrate 11a 1st surface 11b 2nd surface 11c Through-hole 12 Light emitting element 20, 20A Outer casing 21, 22 Opening part 21a Mounting part 21a1 Mounting surface 21b Groove part 23 Rib 23a Screw hole 24 Adhesive 30 Globe ( Translucent cover)
40 circuit unit 50 base 60 screw

Claims (18)

A substrate,
A light emitting device disposed on a first surface of the substrate;
An outer casing holding the substrate,
The said board | substrate is fixed to the said outer housing | casing in the state in which the 2nd surface on the opposite side to the said 1st surface of the said board | substrate is in contact with the said outer housing | casing. The outer casing is a cylindrical cylinder having an opening,
The opening is provided with a mounting portion having a mounting surface for mounting the substrate,
The lighting device according to claim 1, wherein the substrate is in contact with the outer casing by being placed on the placement surface so as to cover the opening. The lighting device according to claim 2, wherein the placement surface has an annular flat surface that constitutes an end surface of the opening. The outer casing has a rib extending from the opening of the outer casing toward the back side along the inner surface of the outer casing,
The lighting device according to claim 2, wherein one end surface of the rib constitutes a part of the mounting surface. The lighting device according to claim 4, wherein a plurality of the ribs are provided along a circumferential direction of the inner surface of the outer casing. The lighting device according to claim 4, wherein at least a part of the light emitting element faces the rib via the substrate. At least one of the ribs is provided with a screw hole extending in the cylinder axis direction of the outer casing,
The substrate is provided with a through hole,
The lighting device according to claim 4, wherein the substrate and the outer casing are fixed by a screw that is inserted into the through hole and screwed into the screw hole. The lighting device according to claim 7, wherein the screw is positioned outside the light emitting element in a top view. The lighting device according to claim 7 or 8, wherein a gap is provided between the shaft portion of the screw and the through hole. Furthermore, the illuminating device of any one of Claims 1-9 provided with the translucent cover which covers the said light emitting element. The lighting device according to claim 10, wherein the translucent cover is made of glass. In the opening, an annular groove is formed outside the mounting portion,
The lighting device according to claim 10 or 11, wherein an end of the opening of the translucent cover is disposed in the groove. The lighting device according to claim 12, wherein the translucent cover and the outer casing are fixed by an adhesive filled in the groove. The lighting device according to claim 13, wherein the groove is formed up to a position facing the second surface of the substrate. And a circuit unit for causing the light emitting element to emit light,
The lighting device according to claim 1, wherein the circuit unit is housed in the outer casing. The lighting device according to claim 15, wherein the circuit unit is housed only in the outer casing. And a base for receiving power for causing the light emitting element to emit light,
The lighting device according to any one of claims 1 to 16, wherein the base is attached to a portion of the outer casing opposite to the opening. The lighting device according to claim 1, wherein the outer casing is made of resin.

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