JP2012252891A - Lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lighting device capable of achieving longer lifetime by improving heat radiation.SOLUTION: The lighting device includes a light source 7 consisting of an LED, a base 2 connected with a commercial power source, a cylindrical heat sink 10 having a mounting surface 13a of the light source 7 at an upper surface and having its lower end connected with the base 2 via an insulating member 3, a fan 20 arranged inside the heat sink 10, an air inlet 10b for absorbing the outside air inside the heat sink 10, and an exhaust port 10c for exhausting from the heat sink 10. An air flow is circulated along a peripheral wall of the heat sink 10 by driving the fan 20.

Description

  The present invention relates to a bulb-type illumination device having an LED light source.

  A conventional light bulb-type lighting device is disclosed in Patent Document 1. This illuminating device includes a light source composed of LEDs inside. A cylindrical lamp base having a base connected to a commercial power source is provided at one end of the lighting device. Inside the lamp base is a light source driving circuit and the like, and an air inlet is opened at the top. A metal fan case forming a heat sink is disposed above the lamp base. The fan case is equipped with a fan, and an exhaust port opens on the peripheral surface. A mounting substrate on which a light source is mounted is disposed on the upper surface of the fan case.

  In the illumination device having the above configuration, when the base is connected to a commercial power source, the light source emits light by the drive circuit. Thereby, illumination of the room etc. is performed. In addition, outside air flows into the lighting device from the air inlet by the drive of the fan, and is exhausted from the air outlet. Thereby, the inside of an illuminating device can be cooled and the heat_generation | fever of the light source which consists of LED can be thermally radiated.

JP 2007-265892 A (page 3 to page 5, FIG. 2)

  In recent years, the brightness of LEDs used as a light source has been increasing year by year, and the amount of heat generated by the light source has increased accordingly. In particular, when a power LED such as that used in a spotlight is mounted, the amount of heat generated by the light source is significantly increased. For this reason, as shown in the conventional lighting device, there is a problem in that the heat radiation of the light source becomes insufficient only by circulating the air flow through the fan, and the life of the light source composed of LEDs is shortened.

  An object of this invention is to provide the illuminating device which can improve heat dissipation and can extend lifetime.

  In order to achieve the above object, the present invention provides a light source comprising an LED, a base connected to a commercial power source, a cylindrical shape having an installation surface of the light source on the upper surface and a lower end connected to the base via an insulating member. A heat sink, a fan disposed inside the heat sink, an intake port for sucking outside air into the heat sink, and an exhaust port for exhausting from the heat sink, and driven by the fan along the peripheral wall of the heat sink It is characterized by circulating air current.

  According to this configuration, when the base is connected to a commercial power source, the light source composed of the LED emits light and the illumination light is emitted. When the fan is driven, outside air is taken into the heat sink from the intake port and exhausted from the exhaust port. At this time, the airflow flows along the peripheral wall of the heat sink, the heat sink is cooled, and the light source installed on the installation surface of the heat sink is cooled.

  Further, the present invention is characterized in that, in the illumination device having the above-described configuration, an air flow is exhausted from the exhaust port toward the cap. According to this configuration, the exhaust from the heat sink flows in the direction of the base and the heat sink is cooled.

  According to the present invention, in the lighting device having the above-described configuration, the heat sink is arranged concentrically with the inner cylinder connected to the insulating member and the inner cylinder with the lower end opened and the annular shape between the inner cylinder and the inner cylinder. An outer cylinder that forms an opening of the fan, and an outlet that opens to the inner cylinder and is disposed on the exhaust side of the fan. The exhaust port is formed by the opening, and the inner cylinder and the An outflow passage for communicating the exhaust port and the outflow port is formed between the outer cylinder and the outer cylinder.

  According to this configuration, the heat sink has a double peripheral wall formed by the inner cylinder and the outer cylinder. External air is taken into the heat sink from the intake port by driving the fan, and flows out from the outlet opening in the inner cylinder. The airflow flowing out from the outflow port flows through the outflow passage along the inner cylinder forming the peripheral wall, and is exhausted from the exhaust port formed by the opening at the lower end of the outer cylinder.

  According to the present invention, in the illumination device having the above-described configuration, the opening is formed by radially dividing an inflow port that is open to the inner cylinder and is disposed on the intake side of the fan, and the inner cylinder and the outer cylinder. A partition plate that divides the exhaust port and the intake port, and an inflow passage that connects the intake port and the inflow port between the inner cylinder and the outer cylinder adjacent to the outflow passage. It is characterized by the formation.

  According to this configuration, the outside air flows into the inflow passage from the intake port formed by the opening at the lower end of the outer cylinder by driving the fan, and flows through the inflow path along the inner cylinder forming the peripheral wall. The airflow flowing through the inflow passage flows into the heat sink through the inflow port.

  According to the present invention, in the lighting device configured as described above, the intake port opens into the insulating member.

  According to the present invention, since the airflow is circulated along the peripheral wall of the heat sink by driving the fan, the contact period between the airflow and the heat sink becomes long, and the heat dissipation of the heat sink can be improved. Thereby, the heat sink and the light source can be sufficiently cooled, and the lifetime of the lighting device can be extended.

The front view which shows the illuminating device of 1st Embodiment of this invention. AA sectional view of FIG. B-O-B cross section of FIG. The figure which shows the temperature distribution at the time of the stop of the fan of the illuminating device of 1st Embodiment of this invention. The figure which shows the temperature distribution at the time of the drive of the fan of the illuminating device of 1st Embodiment of this invention. The figure which shows the flow velocity distribution of the airflow at the time of the drive of the fan of the illuminating device of 1st Embodiment of this invention. Front sectional drawing which shows the illuminating device of 2nd Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a front view of the illumination device of the first embodiment. The lighting device 1 is formed in a light bulb shape having a base 2 at one end, and has a light source 7 composed of LEDs mounted on a mounting substrate 6 inside.

  The outer shape of the lighting device 1 is formed by a base 2, an insulating member 3, a heat sink 10 and a transmission cover 8. The base 2 is formed in, for example, an E26 type and is screwed into a socket supplied with power from a commercial power source. The insulating member 3 is formed in a cylindrical shape from a resin molded product or the like, and is attached to the upper end of the base 2.

  As will be described in detail later, the heat sink 10 has an inner cylinder 11 (see FIG. 2), an outer cylinder 12 (see FIG. 2), and a holding plate 13, and a mounting substrate 6 on which the light source 7 is mounted is installed on the upper surface. The transmission cover 8 is formed in a dome shape, and is fitted and attached to the peripheral portion of the holding plate 13. The transmission cover 8 is formed of a resin that diffuses and transmits the light emitted from the light source 7.

  2 shows a cross-sectional view taken along line AA in FIG. 1, and FIG. 3 shows a cross-sectional view taken along line B-O-B in FIG. A circuit board 21 is erected inside the base 2 and the insulating member 3 and is disposed so as to protrude into the heat sink 10. The circuit board 21 may be held by the base 2 or may be held by the insulating member 3. The circuit board 21 has a drive circuit for the light source 7, converts AC power supplied to the base 2 into DC power, and supplies the DC power to the light source 7.

  The heat sink 10 is formed of a metal such as aluminum, and a disc-shaped holding plate 13 is fitted on the upper surfaces of the inner cylinder 11 and the outer cylinder 12 that are concentrically arranged. Thereby, the heat sink 10 is formed in a bottomed cylindrical shape having a double peripheral wall by the inner cylinder 11 and the outer cylinder 12 and opened downward. An installation surface 13 a of the mounting substrate 6 is formed on the upper surface of the holding plate 13. A lower end of the inner cylinder 11 is connected to the insulating member 3, and a fan 20 formed of a sirocco fan or the like is disposed on the upper part of the inner cylinder 11.

  An annular opening 10 a (see FIG. 1) is formed between the lower end of the outer cylinder 12 and the inner cylinder 11. A space between the outer surface of the inner cylinder 11 and the inner surface of the outer cylinder 12 is divided into a plurality of sections in the circumferential direction by a radial partition plate 16. In the inner cylinder 11, an inlet 11 a disposed on the intake side of the fan 20 is opened facing each adjacent section. Further, the inner cylinder 11 has an outlet 11b that is disposed on the exhaust side of the fan 20 so as to face each section adjacent to the section having the inlet 11a.

  Thereby, between the inner cylinder 11 and the outer cylinder 12, an inflow passage 14 having an inflow port 11a and an outflow passage 15 having an outflow port 11b are formed adjacent to each other on the same circumference. The opening 10a is divided into an intake port 10b and an exhaust port 10c by a partition plate 16. The intake port 10b and the inflow port 11a communicate with each other through the inflow passage 14, and the exhaust port 10c and the outflow port 11b communicate with each other through the outflow passage 15.

  Fins 17 project radially from the inner peripheral surface of the inner cylinder 11. The heat exchange area between the air flowing into the inner cylinder 11 and the heat sink 10 by the fins 17 can be increased, and the heat exchange efficiency of the heat sink 10 can be improved.

  In the illumination device 1 having the above configuration, when the base 2 is connected to a commercial power supply via a socket, the light source 7 emits light by driving the circuit board 21. The light from the light source 7 is diffused and transmitted through the transmission cover 8 to emit illumination light, and the interior of the room is illuminated.

  When the fan 20 is driven, outside air flows into the inflow passage 14 from the intake port 10b as indicated by an arrow A1 (see FIG. 3). The airflow that has flowed into the inflow passage 14 from the intake port 10 b flows through the inflow passage 14 along the inner cylinder 11 and the outer cylinder 12 that form the peripheral wall of the heat sink 10.

  As shown by the arrow A2 (see FIG. 3), the airflow flowing through the inflow passage 14 flows into the inner cylinder 11 through the inflow port 11a. The airflow that has flowed into the inner cylinder 11 passes through the fan 20 and flows out of the inner cylinder 11 through the outlet 11b as indicated by an arrow A3 (see FIG. 3).

  The airflow flowing out from the inner cylinder 11 flows through the outflow passage 15 and is exhausted from the exhaust port 10c facing downward toward the base 2 as indicated by an arrow A4 (see FIG. 3). At this time, the airflow flowing through the outflow passage 15 flows along the inner cylinder 11 and the outer cylinder 12, and the airflow flowing out from the exhaust port 10 c flows along the inner cylinder 11.

  Thereby, the heat sink 10 is cooled by the airflow, and the light source 7 installed on the installation surface 13a of the heat sink 10 is cooled. Further, the circuit board 21 is cooled by the airflow flowing through the heat sink 10 and the heat transfer from the cooled heat sink 10. At this time, since the intake and exhaust of the heat sink 10 circulate along the inner cylinder 11 and the outer cylinder 12 that form the peripheral wall, the contact period between the airflow and the heat sink 10 can be lengthened. Therefore, the heat dissipation of the heat sink 10 can be improved.

  4 shows the temperature distribution of the lighting device 1 when the fan 20 is stopped, and FIG. 5 shows the temperature distribution of the lighting device 1 when the fan 20 is driven. In these drawings, a state cut along a cross section along the circuit board 21 and a vertical cross section is shown in a perspective view. As shown in these drawings, the interior of the lighting device 1 can be sufficiently cooled by driving the fan 20, and the light source 7 and the circuit board 21 are cooled.

  FIG. 6 shows the flow velocity distribution of the airflow in the lighting device 1 when the fan 20 is driven, and shows a cross-sectional view (a) passing through the exhaust port 10c and a cross-sectional view (b) passing through the intake port 10b. As shown in the figure, the exhaust from the exhaust port 10 c circulates along the peripheral wall of the heat sink 10 toward the base 2.

  According to the present embodiment, since the airflow is circulated along the peripheral wall of the heat sink 10 by driving the fan 20, the contact period between the airflow and the heat sink 10 becomes long, and the heat dissipation of the heat sink 10 can be improved. Thereby, the heat sink 10 and the light source 7 can be sufficiently cooled, and the lifetime of the lighting device 1 can be extended.

  Further, since air is exhausted from the exhaust port 10 c facing downward toward the base 2, the airflow can be easily circulated along the peripheral wall of the heat sink 10.

  Further, the heat sink 10 has an inner cylinder 11 and an outer cylinder 12 that are concentrically arranged, and an exhaust port 10 c at the lower end of the outer cylinder 12 and an outlet opening to the inner cylinder 11 between the inner cylinder 11 and the outer cylinder 12. An outflow passage 15 for communicating with 11b is formed. Thereby, while the airflow which flowed out from the outflow port 11b can be distribute | circulated easily along the inner cylinder 11 and the outer cylinder 12, it can be made to exhaust toward the direction of the nozzle | cap | die 2 from the exhaust port 10c.

  In addition, an inflow passage 14 is formed adjacent to the outflow passage 15 so that the partition plate 16 communicates the intake port 10 b at the lower end of the outer cylinder 12 and the inflow port 11 a that opens to the inner cylinder 11. Thereby, the airflow taken in from the inlet 10b can be easily circulated along the inner cylinder 11 and the outer cylinder 12. In addition, the inflow passage 14 and the outflow passage 15 can be arranged on the same circumference, and the lighting device 1 can be downsized.

  Next, FIG. 7 has shown front sectional drawing of the illuminating device 1 of 2nd Embodiment. For convenience of explanation, the same reference numerals are given to the same parts as those in the first embodiment shown in FIGS. In this embodiment, the partition plate 16 and the inflow port 11a (both see FIG. 2) are omitted, and the intake port 3a is provided in the insulating member 3. Other parts are the same as those in the first embodiment.

  Since the partition plate 16 and the inlet 11a (both see FIG. 2) are not provided between the inner cylinder 11 and the outer cylinder 12 of the heat sink 10, an annular outflow passage 15 is formed. Thereby, the whole opening 10a at the lower end of the outer cylinder 12 forms an exhaust port 10c. Moreover, since outside air is taken in into the heat sink 10 from the inlet 3a provided in the insulating member 3, the inflow passage 14 (refer FIG. 2, FIG. 3) is not formed.

  In the illuminating device 1 having the above configuration, when the fan 20 is driven, outside air flows into the inner cylinder 11 of the heat sink 10 from the air inlet 3a as indicated by an arrow A1 (see FIG. 7). The airflow that has flowed into the inner cylinder 11 passes through the fan 20, flows out of the inner cylinder 11 through the outlet 11b, and flows through the outflow passage 15 as shown by an arrow A3 (see FIG. 7).

  The airflow flowing through the outflow passage 15 is exhausted from the exhaust port 10c facing downward toward the base 2 as shown by an arrow A4 (see FIG. 7). At this time, the airflow flowing through the outflow passage 15 flows along the inner cylinder 11 and the outer cylinder 12 forming the peripheral wall of the heat sink 10, and the airflow flowing out from the exhaust port 10 c flows along the inner cylinder 11.

  Thereby, the heat sink 10 is cooled by the airflow, and the light source 7 installed on the installation surface 13a of the heat sink 10 is cooled. Further, the circuit board 21 is cooled by the airflow flowing through the heat sink 10 and the heat transfer from the cooled heat sink 10.

  According to the present embodiment, as in the first embodiment, since the air flow is circulated along the peripheral wall of the heat sink 10 by driving the fan 20, the contact period between the air flow and the heat sink 10 becomes long, and the heat dissipation of the heat sink 10 is improved. Can be improved. Thereby, the heat sink 10 and the light source 7 can be sufficiently cooled, and the lifetime of the lighting device 1 can be extended.

  Further, since air is exhausted from the exhaust port 10 c facing downward toward the base 2, the airflow can be easily circulated along the peripheral wall of the heat sink 10.

  In addition, since the air inlet 3 a opens in the insulating member 3 disposed below the heat sink 10, a sufficient air flow can be circulated in the lower part of the heat sink 10. Therefore, the heat dissipation of the heat sink 10 can be further improved. In addition, the airflow can be sufficiently circulated in the vicinity of the circuit board 21 erected in the insulating member 3, and the circuit board 21 can be further cooled.

  According to the present invention, it can be used for a bulb-type lighting device having an LED light source.

DESCRIPTION OF SYMBOLS 1 Illuminating device 2 Base 3 Insulating member 6 Mounting board 7 Light source 8 Transmission cover 10 Heat sink 10b Intake port 10c Exhaust port 11 Inner cylinder 11a Inlet 11b Outlet 12 Outer cylinder 13 Holding plate 14 Inflow passage 15 Outflow passage 16 Partition plate 17 Fin 20 Fan 21 Circuit board

Claims (5)

  A light source composed of LEDs, a base connected to a commercial power source, a cylindrical heat sink having an installation surface of the light source on the top surface and a lower end connected to the base via an insulating member, and disposed inside the heat sink An illuminating device comprising: a fan, an air intake port for sucking outside air into the heat sink; and an exhaust port for exhausting air from the heat sink, wherein the air flows along the peripheral wall of the heat sink by driving the fan. .   The lighting device according to claim 1, wherein an air flow is exhausted from the exhaust port toward the base.   An inner cylinder connected to the insulating member, an outer cylinder that is concentrically arranged with the inner cylinder and that opens an lower end to form an annular opening between the inner cylinder and the inner cylinder; An outlet that is open to a cylinder and is disposed on the exhaust side of the fan, and the exhaust port is formed by the opening, and the exhaust port and the outlet are provided between the inner cylinder and the outer cylinder. The lighting device according to claim 1, wherein an outflow passage that communicates with the outlet is formed.   An inflow opening that is open to the inner cylinder and is arranged on the intake side of the fan, and the inner cylinder and the outer cylinder are radially partitioned to divide the opening into the exhaust port and the intake port. The partition plate is provided, The inflow channel which connects the said inlet and the inflow port between the said inner cylinder and the said outer cylinder was formed adjacent to the said outflow channel, The Claim 3 characterized by the above-mentioned. Lighting equipment.   The lighting device according to claim 3, wherein the intake port opens in the insulating member.

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