JP2010198828A - Lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting device capable of efficiently reducing increase in temperature of LEDs when it is on, in spite of having the LEDs arranged in a sealed space within the device. <P>SOLUTION: The lighting device 100 includes: a printed circuit board 14; light-emitting means 14C mounted on the printed circuit board 14; a heat dissipating member 123 for dissipating heat emitted from the light-emitting means 14c; and a translucent cylindrical case 10 for arranging the printed circuit board 14c, the light-emitting means 14c and the light-emitting member 123 therein. The light dissipating member 123 is cylindrical and has a flat portion 11g on its outer side surface, and the circuit board 14 is connected to the flat portion 11g. The cylindrical case 10 and the heat dissipating member 123 together form a sealed space within the cylindrical case 10, and the inside of the heat dissipating member 123 and the ambient air are made to communicate with each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lighting device including a printed circuit board on which an LED as a light emitting means is mounted, and a heat radiating member for radiating heat generated from the LED.

Conventionally, for example, a fluorescent lamp (straight tube) has been used as an illumination device for illuminating the inside of a machine tool. Fluorescent lamps are prone to deterioration or breakage due to metal scraps or lubricating oil scattered during metal processing by machine tools, so it was necessary to protect them with tempered glass to protect the fluorescent lamps from metal scraps and lubricating oil.
However, since it is difficult to process tempered glass into a complicated shape, it was generally processed into a cylindrical shape. In addition, a cylindrical tube is generally used because of its advantages that it can be waterproofed relatively easily and can illuminate a wide area if it is cylindrical.
And in consideration of environmental problems, an illuminating device using an LED with a small amount of CO2 emission is often used instead of a fluorescent lamp. Since the LED light is directional, since the LED is mounted on a printed circuit board and used for illumination, illumination on the back surface of the printed circuit board is eliminated, and the use of a cylindrical tube is reduced.
Further, since it is necessary to add a heat dissipation structure to the back surface of the printed circuit board in order to dissipate heat generated by the LED, a box-type lighting device using an LED has become common.
However, when replacing a fluorescent lamp with an LED, an illuminating apparatus having the same shape and the same illumination range as a fluorescent lamp has been desired, so that an LED illuminating apparatus using a tempered glass cylindrical tube has been seen (for example, Patent Document 1).

  The illuminating device of Patent Document 1 has a cylindrical portion that is open at both ends, and the opening at both ends is closed by a positioning sleeve. The inside of the cylindrical portion is a sealed space, and a cylindrical mounting base portion that is divided in half into the sealed space of the cylindrical portion is disposed. A rectangular heat radiating plate is provided along the opening surface inside the mounting base, and both side edges of the heat radiating plate are supported by the inner wall surface of the mounting base. A printed circuit board is bonded to the upper surface of the heat radiating plate, and an LED is mounted on the printed circuit board. A heat radiating space is formed by the peripheral wall of the mounting base and the heat radiating plate.

  When the LED is turned on, the heat generated in the LED is radiated to the heat radiating space through the heat radiating plate, thereby cooling the LED.

Utility Model Registration No. 3121894

  However, in such an illuminating device, since the heat radiation space is formed in a sealed space, it is difficult to dissipate the heat radiated from the heat radiation plate to the outside of the cylindrical portion. Therefore, the temperature in the sealed space rises, it is difficult to suppress the temperature rise of the printed circuit board and electronic components such as LEDs mounted on the printed circuit board, and it is difficult to say that it has sufficient heat dissipation. .

In order to solve this problem, the heat dissipation plate may be directly bonded to the inner peripheral wall of the cylindrical portion. However, in order to bond this heat dissipation plate to the printed circuit board, it must be formed in a flat plate shape. It cannot be surface-bonded to the inner peripheral wall of.
Moreover, the illumination device of Patent Document 1 has a complicated structure, and it is not easy to replace the LED inside the illumination device.

  There is also known an illuminating device in which heat radiation efficiency is improved by providing a metal tube end metal for heat radiation at the end of the cylindrical portion and connecting both ends of the heat radiation plate to the metal tube end metal. However, since only both ends of the heat radiating plate are connected to the cylindrical tube end metal, even such an illuminating device cannot sufficiently dissipate the heat generated from the LED. Furthermore, if the thickness of the cylindrical tube end metal is increased to increase the heat dissipation efficiency in order to increase the heat dissipation efficiency, the weight of the lighting device increases.

  Further, if the forward current is suppressed to reduce the amount of heat generated by the LED, it is necessary to increase the number of LEDs mounted in order to obtain the required illuminance, resulting in a large cylindrical portion.

    The present invention has been made paying attention to the above problem, and can efficiently dissipate the heat of the light emitting means provided in the sealed space inside the cylindrical case, and can easily replace the light emitting means. The purpose is to provide.

In order to achieve the above object, according to the present invention, a printed circuit board, a light emitting means mounted on the printed circuit board, a heat radiating member for radiating heat generated from the light emitting means, the printed circuit board, and the light emission A lighting device comprising a translucent cylindrical case for disposing means and the heat dissipating member therein,
The heat dissipation member is cylindrical and has a flat portion on the outer surface,
Bonding the printed circuit board to the flat part,
A sealed space is formed in the cylindrical case by the cylindrical case and the heat radiating member, and the inside of the heat radiating member communicates with the outside air.

  According to this invention, the heat of the light emitting means provided in the sealed space inside the cylindrical case can be efficiently radiated. Further, the LED inside the lighting device can be easily replaced.

It is a perspective view of the illuminating device of Example 1. FIG. It is sectional drawing of the illuminating device which follows the KK line | wire of FIG. It is a disassembled perspective view of the illuminating device of Example 1. FIG. FIG. 3 is a front view of an end fitting pipe of the first embodiment. FIG. 5 is a cross-sectional view of an end fitting pipe along line LL in FIG. 4. FIG. 5 is a rear view of the end fitting tube of FIG. 4. It is assembly explanatory drawing of the illuminating device of Example 1. FIG. It is assembly explanatory drawing of the illuminating device of Example 1. FIG. 6 is a diagram illustrating another example of the first embodiment. FIG. It is a figure which shows the illuminating device of Example 2. FIG. It is a figure which shows the illuminating device of Example 3. FIG.

  Hereinafter, the best mode for realizing the illumination device of the present invention will be described based on Examples 1 to 4 shown in the drawings.

  First, the structure of the illuminating device of Example 1 which concerns on this invention is demonstrated.

  FIG. 1 is a perspective view of the lighting apparatus according to the first embodiment. FIG. 2 is a cross-sectional view of the lighting device along the line KK in FIG. FIG. 3 is an exploded perspective view of the lighting apparatus according to the first embodiment.

  As shown in FIGS. 1 to 3, the illumination device 100 according to the first embodiment includes a printed circuit board 14, high-intensity LEDs (light emitting means) 14 c mounted on the printed circuit board 14, A heat radiating plate 11 and a metal plate 12 for radiating heat generated from the luminance LEDs 14c,..., A translucent cylindrical case 10 having both ends opened, and openings 10a, 10b at both ends of the cylindrical case 10 are provided. A pair of end fittings 15A and 15B that are closed and sealed inside, and a heat sink 11, the metal plate 12, and a pair of end fittings 15A and 15B for holding the end fitting tubes in the cylindrical case 10. 21 and 21 etc.

  Reference numeral 18 denotes an annular fitting for attaching the illumination device 100 to an internal wall surface of a machine tool or the like.

  The heat radiating plate 11 and the metal plate 12 constitute a heat radiating member 123. Further, the end fittings 15A and 15B and the end fitting tubes 21 and 21 constitute a pair of lid members.

  The length in the longitudinal direction of the printed circuit board 14 is set shorter than that of the cylindrical case 10, and the width in the short direction is set slightly smaller than the inner diameter of the cylindrical case 10.

  Further, a plurality of screw holes 14f,... Are formed in the printed circuit board 14 at predetermined intervals. A plurality of high-brightness LEDs 14c,... Are mounted on the printed circuit board 14 at predetermined intervals.

  At the left end in the longitudinal direction of the printed circuit board 14 (in FIG. 3), a power cable connector 14e is provided.

  The heat sink 11 is made of a metal such as aluminum or iron, and the width in the short direction is set to be substantially the same as that of the printed circuit board 14. Both side end surfaces of the heat sink 11 in the short direction are inclined downward (in FIG. 7).

  The length of the heat sink 11 in the longitudinal direction is set to be substantially the same as that of the cylindrical case 10.

  In the heat radiating plate 11, screw holes 11b,... Are formed at locations corresponding to the plurality of screw holes 14f of the printed circuit board 14.

  The metal plate 12 is made of a metal such as aluminum or iron, and as shown in FIG. 7, support plate portions 12e and 12f are continuously formed at a predetermined angle on a base portion 12g and both side edge portions. The cross section of the metal plate 12 has a substantially concave shape (in FIG. 7).

  The distance between the edge portions 12c and 12d of the support plate portions 12e and 12f of the metal plate 12 is set to be substantially the same as the width of the heat radiating plate 11 in the short direction. The length of the metal plate 12 in the longitudinal direction is set to be substantially the same as that of the heat radiating plate 11. The angle formed by the inner side surfaces 12ea and 12fa of the support plate portions 12e and 12f of the metal plate 12 is set to be the same as the angle formed by both side end surfaces of the heat sink 11 in the short direction.

  The end fittings 15 </ b> A and 15 </ b> B are made of metal such as aluminum or iron, and are formed in a disk shape having substantially the same diameter as the inner diameter of the cylindrical case 10. Further, screw holes 15Aa,..., 15Ba,... Are formed at equal intervals along the periphery in the vicinity of the periphery of the end fittings 15A, 15B.

  Further, openings 15Ac and 15Bc having substantially inverted trapezoidal shapes (in FIG. 3) are formed in the end fittings 15A and 15B (see FIG. 7). Further, a through hole 15Ab for the wire through metal fitting 16 to be described later is formed on the opening 15Ac of the end fitting 15A.

The end fitting pipe 21 is made of a metal such as aluminum or iron, and is formed in a cylindrical shape having both ends opened as shown in FIGS. A large-diameter hole 21a and a small-diameter hole 21b are continuously formed in the end fitting pipe 21.
Further, on the outer peripheral surface 21ac of the end fitting tube 21, a guideline 21ad for attaching the illumination device 100 to the machine tool is drawn on the central axis viewed from the direction in which the high-intensity LED 14 is viewed in plan (see FIG. 8). ).

  An annular groove 21 c is formed on the inner side surface 21 bd of the end fitting pipe 21. Further, the inner diameter of the annular groove 21 c is set substantially the same as the inner diameter of the cylindrical case 10. The outer diameter of the annular groove 21 c is set to be substantially the same as the outer diameter of the cylindrical case 10.

  A packing 20 shown in FIG. 3 is provided in the annular groove 21c (see FIG. 2).

  Further, screw holes 21ba,... Corresponding to the screw holes 15Aa,..., 15Ba,... Of the end fitting pipes 15A, 15B are formed in a portion inside the annular groove 21c of the inner side surface 21bd. .

  The annular fitting 18 has an annular portion 18a that holds the end fitting pipe 21 and a pair of L-shaped arm portions that support the annular portion 18a. A plurality of guide lines 18c,... Are drawn at equal intervals on the outer peripheral surface of the annular portion 18a.

  The wire penetration hardware 16 is formed with a small-diameter fitting portion 16a that fits into the through hole 15Ab of the end fitting 15A. Further, the through-hole metal fitting 16 is formed with a through hole 16c through which the power supply line 17 is passed.

  As described above, the heat radiating plate 11, the metal plate 12, the end fittings 15A and 15B, and the end fitting tube 21 are made of metal such as aluminum or iron, but have high thermal conductivity and formability. If it is, it will not be restricted to the said material.

  Next, assembly of the illumination device of the present embodiment will be described with reference to FIGS. 3, 7, and 8. FIG.

  As shown in FIG. 7, the heat radiating plate 11 is disposed between the upper portions of the support plate portions 12 e and 12 f of the metal plate 12 to form a heat radiating member 123 having a trapezoidal cross section as a heat radiation space.

  Then, both ends of the heat radiating member 123 are fitted into the openings 15Ac and 15Bc of the end fittings 15A and 15B, respectively, and the outer side surfaces 15Ae and 15Be of the end fittings 15A and 15B and the both end faces of the heat radiating member 123 are respectively faced. One.

  The fitting portion 16a of the wire through metal fitting 16 shown in FIG. 3 is fitted into the through hole 15Ab of the end fitting 15A (see FIG. 2), and the power supply side of the feeder 17 connected to the connector 14e of the printed circuit board 14 Is pulled out through the through hole 16c of the wire through metal fitting 16 (see FIG. 2).

  Next, the heat dissipating member 123, the printed circuit board 14, the end fittings 15A and 15B, and the like are arranged in the cylindrical case 10 as shown in FIG.

  Thereafter, as shown in FIG. 2, both ends 10 a and 10 b of the cylindrical case 10 are inserted into the annular grooves 21 c and 21 c of the end fitting pipes 21 and 21 to which the packings 20 and 20 are attached.

  Thus, both ends 10a and 10b of the cylindrical case 10 are brought into close contact with the packings 20 and 20, and the outer side surfaces 15Ae and 15Be of the end fittings 15A and 15B are brought into contact with the inner side surface 21bd of the end fitting pipes 21 and 21, respectively. Make contact. Due to this contact, the openings at both ends of the heat radiating member 123 face the small-diameter holes 21b and 21b of the end fitting pipes 21 and 21, respectively.

  Then, the screw holes 15Aa,..., 15Ba,... Of the end fittings 15A, 15B and the screw holes 21ba,... Of each end fitting tube 21 are screwed through a washer Zk with waterproof packing, The end fittings 15A and 15B are fixed to the end fitting pipes 21 and 21, respectively. Based on this screwing, the washer Zk closes all the screw holes.

  Based on the above-described assembly, the heat radiating space in the heat radiating member 123 is formed in the cylindrical case 10 via the openings 15Ac and 15Bc of the end fittings 15A and 15B and the small diameter holes 21b and 21b of the end fitting tubes 21 and 21. While communicating with the outside, the space between the cylindrical case 10 and the heat radiating member 123 is sealed (see FIG. 2). At this stage, the assembly of the lighting device 100 is completed.

  The illuminating device 100 is attached to a predetermined position inside the machine tool by annular fittings 18 and 18, for example, on the inner wall so that the axis of the cylindrical case 10 is in the direction along the vertical direction.

  Next, the operation of the illumination device of the present embodiment will be described with reference to FIGS.

  When the high-intensity LED 14c is turned on, the temperature of the high-intensity LED 14c increases. The heat of the high-intensity LED 14c is transmitted to the printed circuit board 14, and the temperature of the printed circuit board 14 rises. Moreover, the heat of the printed circuit board 14 and the heat of the high-intensity LED 14c are radiated to the sealed space of the cylindrical case 10, and the temperature of the sealed space rises.

Since the lower surface 14 b of the printed circuit board 14 is in contact with the upper surface 11 g of the heat radiating plate 11, the heat of the printed circuit board 14 is radiated to the heat radiating space of the heat radiating member 123 through the heat radiating plate 11.
Since the heat radiating space of the heat radiating member 123 communicates with the outside air through the small-diameter hole 21b of the end fitting tube 21, the heat radiated to the heat radiating space is radiated to the outside air.
That is, the heat of the high-intensity LED 14 c in the sealed space is directly radiated to the outside air through the heat radiating plate 11.
The end fittings 15A and 15B are joined to the heat radiating member 123 for waterproofing, and are exposed to the outside of the cylindrical case 10 through the small diameter holes 21b and 21b of the end fitting pipes 21 and 21. .
Heat conduction from the heat dissipating member 11 raises the temperature of the end fittings 15A and 15B, and the heat of the end fittings 15A and 15B further conducts heat to the end fitting tubes 21 and 21. Then, heat is radiated from the end fittings 15A and 15B and the end fitting pipes 21 and 21 to the outside air.

  Thus, the heat in the heat radiation space is radiated from the end fittings 15A, 15B, 21, 21 to the outside of the cylindrical case 10, so that the printed circuit board 14 and the high-intensity LEDs 14c mounted on the printed circuit board 14 are provided.・ ・ Efficiently dissipates heat from electronic components such as

  For this reason, the temperature rise of the high-intensity LED 14c in use can be suppressed as compared with the conventional one, and the high-intensity LED 14c and the surrounding electronic components can be suppressed from becoming high temperature. Thereby, the temperature of the high-intensity LED 14c in use and the surrounding electronic components can be maintained within the allowable range of each electronic component.

  As a result, it is possible to suppress the shortening of the lifetime of the high-brightness LED 14c and other electronic components due to the heat of the high-brightness LED 14c.

  By the way, since the heat radiation efficiency can be improved as described above, if the temperature of the high-brightness LED 14c and other electronic components is within the allowable range even if the heat generation of the high-brightness LED is increased, the high-brightness LED 14c. It is also possible to increase the illuminance of the lighting device 100 by increasing the forward current.

  9 is another example of the first embodiment in which the heat radiation fins 110c,... Are integrally formed on the heat radiation plate 11 of the first embodiment and the heat radiation fins 110c,.

  Since the surface area of the heat radiating member 124 for radiating heat to the heat radiating space by the heat radiating fins 110c is increased as compared with the heat radiating member 123 of the first embodiment, the heat radiating efficiency of the heat from the high brightness LED 14c can be further increased. . Instead of the heat radiation fins 110c,..., Heat pipes or the like may be attached to increase the heat radiation efficiency.

  FIG. 10 illustrates an illumination device 200 according to the second embodiment.

The lighting device 200 includes three printed circuit boards 140f, 140g, and 140h arranged along the axis of the cylindrical case 10, and a printed circuit board body 140 in which the edges of the adjacent printed circuit boards are in contact with each other. And a heat sink 112 in contact with the back surface of the printed circuit board body 140.
High-brightness LEDs 14c are mounted on the surface of the printed circuit boards 140f, 140g, and 140h of the printed circuit board body 140, and the printed circuit boards 140f, 140g, and 140h are directed in different outward directions.

  The distance between both ends of the heat sink 112 in the short direction is set to be slightly smaller than that of the printed circuit board 140 as in the first embodiment.

  Reference numeral 150B denotes an end fitting for holding one end of a heat radiating member, which will be described later, and the end fitting 150B is formed with a through hole 150Bc for mounting the heat radiating member 132 composed of the metal plate 12 and the heat radiating plate 112. Has been. The through holes 150Bc have substantially the same shape as the hexagonal openings at both ends of the heat dissipation member 132. A through hole 150Ac similar to the through hole 150Bc is formed in the end fitting 150A (not shown).

  In addition, the same code | symbol is attached | subjected to the member same as Example 1, and the description is abbreviate | omitted.

  According to the illumination device of the second embodiment, the same effects as in the first embodiment can be obtained, and the printed circuit boards 140f, 140g, and 140h of the printed circuit board body 140 are directed in different outer directions. Therefore, it can illuminate over a wide range.

  Moreover, since the heat sink 112 is bent to increase the contact area with the heat dissipation space, the heat dissipation effect of the heat sink 112 is enhanced as compared with the first embodiment.

  For this reason, the temperature rise of electronic components, such as the printed circuit board 140 and the high-intensity LED 14c mounted in this, by the heat emitted from the high-intensity LED 14c can be suppressed.

  By suppressing the temperature rise of the high-brightness LED 14c, the forward current of the high-brightness LED 14c can be increased as compared with the first embodiment. For this reason, even if the number of high-brightness LEDs 14c is reduced, the same illuminance as that of the first embodiment can be obtained. In other words, higher illuminance than that of the first embodiment can be obtained with the same number of high-brightness LEDs 14c.

  A plurality of printed circuit boards 140f, 140g, and 140h are arranged as shown in FIG. 10 so that the printed circuit board of the first embodiment can be accommodated in the cylindrical case 10 without changing the lateral width in plan view. The heat dissipating space of the heat dissipating member 123 can be expanded without changing the size of 10 and the heat dissipating efficiency can be further increased as compared with that of the first embodiment.

  As in another example of the first embodiment, the heat radiating fins 110c may be integrally provided on the inner surface of the heat radiating plate 112 of the second embodiment, or a heat pipe may be attached.

  FIG. 11 shows an illumination apparatus of Example 3.

  As shown in FIG. 11, the illumination device 300 according to the third embodiment arranges eight printed circuit boards 141,... In an annular shape along the axis of the cylindrical case 10, and makes the edges contact each other to form an octagon. , And a plurality of flat portions corresponding to the printed circuit boards 141,..., And the plurality of flat portions are inner side surfaces (back surfaces) of the plurality of printed circuit boards. And a heat radiating plate 113 in contact with 141d. The heat radiating plate 113 is formed in an octagonal cylindrical shape having both ends opened.

  High brightness LEDs 14c,... Are mounted on each outer surface 141c of the printed circuit board body 141 at predetermined intervals along the longitudinal direction of the printed circuit board body 141, and each outer surface 141c faces a different outer direction. It has been.

  A through hole 151Bc having substantially the same shape as the opening end of the heat dissipation plate 113 is formed in the end fitting 151B. A through hole 151Ac similar to 151Bc is also formed in 151A (not shown).

  In addition, the same code | symbol is attached | subjected to the member same as Example 1, 2, and the description is abbreviate | omitted.

  According to the illumination device 300 of the third embodiment, the same effects as those of the first and second embodiments can be obtained, and the outer surfaces 141c of the printed circuit board body 141 are directed in different outward directions. Therefore, it can illuminate over a wider range (360 ° range).

  Since the printed circuit board body 141 is formed in an octagonal cylindrical shape, the mounting area of the high-brightness LEDs 14c on the printed circuit board body 141 can be increased, and therefore the number of high-brightness LEDs 14c to be mounted can be increased. it can.

  Increasing the number of high-brightness LEDs 14c to be mounted increases the total heat generation amount of the high-brightness LEDs 14c. However, since the heat radiation area and the heat radiation space of the heat sink 113 formed in an octagonal cylindrical shape can be increased, It is possible to sufficiently suppress the temperature rise of the luminance LED 14c and other electronic components.

  In the first to third embodiments, the example in which the polygonal heat dissipation member is applied to the cylindrical lighting device has been described. However, the device has a sealed structure including a heating element, and includes a sealed structure wall. Other devices can be applied as long as the heat dissipating member constituting the unit can be installed inside the device.

DESCRIPTION OF SYMBOLS 10 Cylindrical case 11g Flat part 14 Printed circuit board 14c Light emission means 100 Illuminating device 123 Heat dissipation member

Claims (4)

A printed circuit board, a light emitting means mounted on the printed circuit board, a heat radiating member for radiating heat generated from the light emitting means, and the printed circuit board, the light emitting means, and the heat radiating member are disposed inside. A lighting device having a translucent cylindrical case,
The heat dissipation member is cylindrical and has a flat portion on the outer peripheral surface,
Bonding the printed circuit board to the flat part,
An illuminating device characterized in that a sealed space is formed in the cylindrical case by the cylindrical case and the heat radiating member, and the inside of the heat radiating member communicates with the outside air. A plurality of the printed circuit boards are arranged along the axis of the cylindrical case,
The lighting device according to claim 1, wherein a plurality of flat portions of the heat radiating member are provided corresponding to the plurality of printed circuit boards, and the plurality of printed circuit boards are joined to the plurality of flat portions, respectively.   The illuminating device according to claim 1 or 2, wherein a radiating fin protruding into an internal space of the radiating member is integrally formed on an inner surface of the radiating member. Both ends of the cylindrical case are open,
The heat dissipating member is polygonal,
A pair of discs having openings is provided, and both ends of the heat radiating member are fitted to the respective openings, and the discs are attached to both ends of the heat radiating member,
A pair of metal lid members are provided at the openings at both ends of the cylindrical case to close the openings, and an opening is formed in each of the pair of lid members, and the internal space of the heat radiating member is opened to the outside via the openings. The lighting device according to claim 1, wherein the lighting device is in communication.

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