JP5531209B2 - LED substrate, LED lighting unit and LED lighting device - Google Patents

Description

  The present invention relates to a substrate on which an LED is mounted (hereinafter referred to as an LED substrate), an LED illumination unit using the LED substrate, and an LED illumination device configured by connecting a plurality of the LED illumination units.

In recent years, research and technology development of light emitting diodes (hereinafter referred to as LEDs) has progressed tremendously, and as a result, LEDs that can be used in a wider range of applications have been developed. Recently, in the field of lighting technology, This LED has come to be used as a light source.
When LEDs are used in lighting technology, they have characteristics such as extremely high energy efficiency, long life of LED elements, and low power consumption compared to conventional light sources such as incandescent bulbs and fluorescent lamps. In addition, since the LED element alone is very small, there is an advantage that it can be mounted in a small space.
Even if this LED has low power consumption, but becomes high output, heat is stored in the LED, and the temperature of the LED element rises. In particular, when a large number of high-power LEDs are arranged in a narrow mounting space, the temperature rises quickly and abnormal overheating may occur. Since this LED is a semiconductor device, when it is abnormally overheated, its characteristics change, causing a failure such as a decrease in luminous efficiency. As a countermeasure, the LED lighting substrate used in the lighting device is provided with a heat radiating means for efficiently radiating the heat generated from the LED to the outside.

FIG. 8 shows an already known LED illumination substrate, in which FIG. 8 (a) is a schematic plan view and FIG. 8 (b) is a side view.
The LED illumination board 40 includes an LED 41, a rectangular printed wiring board 40 on which the LED is mounted, and a pair of first and second electrical connectors 46A and 46B. The printed wiring board 40 includes: The LED 41 is provided at a substantially central portion of the surface, the first electrical connector 46A is provided at one end of the same surface, and the second electrical connector 46B is provided at the other end, and these are on the insulating coating provided on the surface of the printed wiring board. The wiring patterns 45A, 45B, and 45C are electrically connected. The LED 41 includes a plurality of light emitting elements inside, and a plurality of terminals are led out to the outside, and these terminals are connected to the wiring patterns 45A and 45B. That is, the plurality of light emitting elements are connected in series between the wiring patterns 45A and 45B.
The printed wiring board 40 includes a base 43 made of relatively thick aluminum having a rectangular shape having long sides facing each other and a short side connecting the ends of the long sides, and an insulating material applied to the upper surface of the base The coating layer 44 and wiring patterns 45A, 45B and 45C wired on the insulating coating layer 44 are formed. Further, the printed wiring board 40 mounting hole 42 ₁ for attaching to equipment near the four corners are formed. The components are attached to the printed wiring board 40 by first fixing the bottom surface of the LED 41 on the land 45D formed on the insulating coating layer 44 in the center of the board by soldering, and connecting both terminals of the LED 41 to the wiring pattern 45A, Electrical connection is made to 45B. On one short side, the first electrical connector 46A is fixed, and the terminals in the electrical connector are electrically connected to the wiring pattern connected to the LED 41. The second electrical connector 46B is fixed to the other short side, and the terminals in the electrical connector are electrically connected to the wiring pattern connected to the LED 41. The first electrical connector 46A is connected to a power source (not shown), and the second electrical connector 46B is connected to another LED illumination board (not shown) connected thereto.

  Patent Document 1 below discloses an LED surface emitting device in which a diamond substrate having a predetermined size is used, and an LED is fixed on the diamond substrate with an adhesive.

  Further, Patent Document 2 below discloses a planar illumination device that uses a flexible printed circuit board and has LEDs fixed to the flexible printed circuit board.

JP 2002-329896 A (paragraph [0020], FIG. 3) JP 2006-310123 A (paragraph [0019], FIG. 2)

  In the known LED illumination board 40, since LEDs are mounted on a printed wiring board and the printed wiring board becomes expensive, it is difficult to reduce the cost of the entire board. In particular, when an LED lighting board is mounted on a lighting unit, and the lighting device includes a large number of lighting units, the cost of the entire device increases. Further, since the LED is fixed on the land, which is a conductive pattern formed on an insulating layer provided on the printed wiring board, heat from the LED is difficult to conduct to the base material, and therefore the heat dissipation effect is deteriorated. . In addition, since a pair of electrical connectors are mounted on the surface of the wiring board on which the LEDs are mounted, if this LED board is accommodated in the lighting housing, it becomes an obstacle to light reflection in the housing, and the diffusion panel. For example, the shape is projected and the lighting quality is deteriorated.

  Further, the LED surface light emitting device of Patent Document 1 has a very high thermal conductivity while diamond is an electrical insulator, so that the heat generated from the LED is transmitted to the diamond substrate via the adhesive layer and externally connected. To be released efficiently. However, since this LED substrate has to use expensive diamond, the price of the LED substrate is so high that it is difficult to use it except for special applications such as the illustrated surgical lighting device. . Furthermore, the planar illumination device of Patent Document 2 is suitable for an edge-type backlight using a light guide panel, but cannot be used for a general illumination device. In recent years, various types of LEDs have been developed, but those with special structures generally have a high price, and there is a problem that when used in a general lighting device, the price of the device increases and the cost cannot be reduced.

The present invention has been made to solve such problems of the prior art, and the object of the present invention is to use an LED that is versatile and relatively inexpensive, and can efficiently dissipate heat generated from the LED. And it is providing the LED board which can comprise a board | substrate cheaply.
Another object of the present invention is to provide a thin and inexpensive LED lighting unit and an LED lighting device including the LED lighting unit, which can obtain uniform illumination light by using an LED substrate having the above object. There is.

In order to solve the above-mentioned problem, an invention related to an LED substrate of the present application includes a light emitting diode (hereinafter referred to as LED), a mounting substrate on which the LED is mounted, and a wiring substrate disposed on the mounting substrate surface. The mounting board is made of a heat sink having a predetermined thickness and area, the wiring board is made of an insulating sheet provided with LED connection lines, and the mounting board has a predetermined surface on the heat sink. First and second areas are divided, the wiring board is disposed in one of the first and second areas, and an electrically conductive layer is disposed in the other area. The LED is directly fixed to the electrically conductive layer or the empty space by the heat dissipation surface, one terminal of the LED is connected to the LED connection line, the other terminal is connected to the electrically conductive layer, and the wiring board includes: Articulated A feed line connected in series to another LED lighting board is provided, and the LED connection line and the feed line of the wiring board are provided with a wiring terminal connected to an external wiring at an end of each wiring, The mounting board is formed with a through hole or a narrow groove penetrating the mounting board at a position corresponding to the wiring terminal of the wiring board, and a through hole or a surface located on a surface opposite to the surface on which the wiring board is disposed. An electrical connector is attached to a portion surrounding the narrow groove .

  The LED substrate is characterized in that the electrically conductive layer is provided on the entire surface of the heat radiating plate, and the wiring substrate and the LED are provided on the electrically conductive layer.

  In the LED substrate, the heat dissipation plate is formed of aluminum, and the electric conductive layer is formed of a metal material such as copper or gold.

  The invention relating to the LED lighting unit of the present application includes an LED, a housing in which the LED is mounted on the bottom and having an opening and an inner wall surface formed of a reflective material, and an optical reflection having high reflectivity covering the opening of the housing. The optical reflection plate has a central reflection portion having a predetermined area directly above the LED, and an outer reflection portion formed on the outer periphery of the central reflection portion, and the housing is formed on the bottom portion of the optical reflection plate. The exposure hole that exposes the light emitting part of the LED and a locking means integrally formed with the bottom member are provided on the bottom back wall near the periphery of the exposure hole, and the LED board is fixed by the locking means. It is characterized by that.

  In the LED lighting unit, the central reflecting portion is provided directly above the LED, and is provided in a small central reflection area with low light transmittance and high light reflectance, and around the central reflection area. It consists of a central peripheral reflection area with low transmittance, and the outward reflection part is formed with an opening through which a plurality of reflected light whose opening area is increased from the central peripheral reflection area toward the radial direction. It is characterized by that.

In the LED illumination unit, the minimum distance from the center of the radiation surface of the optical reflector facing the LED to the opening along the radiation surface is x, and the optical axis direction from the LED to the optical reflector is When the separation distance is d, the opening dimension of the opening is a, and the thickness of the outer reflection portion is t,
d / x <t / a
It has the relationship of these.

  In the LED illumination unit, the through hole has the opening on the reflection surface and the radiation surface of the outer reflection portion, the opening on the radiation surface side is on the central reflection portion side, and the opening on the reflection surface side is on the reflection surface side. It is characterized by being formed with inclined holes that are unevenly distributed in the direction away from the central reflecting portion side.

  The LED illumination unit is characterized in that the through hole has a gradually inclined slope from the center peripheral reflection area toward the radial direction.

Said LED illumination unit makes the ratio of the area sum of the said opening with respect to the preset reference area the opening ratio A (area of the opening of the predetermined part / reference area),
When b and c are constants and x is the minimum distance from the center of the radiation surface of the optical reflector facing the point light source to the opening along the radiation surface, approximately A = bx ² + c
It has the relationship of these.

  The invention relating to the LED lighting device of the present application is characterized by being configured by arranging a plurality of the LED lighting units described above.

  According to the invention related to the LED substrate, it is possible to provide an LED substrate suitable for an LED lighting device that can use a versatile and relatively inexpensive LED and an inexpensive heat sink. That is, even if such an LED is used, the LED can be directly fixed to the heat radiating plate, so that heat from the LED is efficiently transmitted to the heat radiating plate, and abnormal overheating of the LED can be prevented. Further, since the wiring board having the minimum necessary size is used, the LED board can be manufactured at low cost without using an expensive wiring board having a large area as the heat sink.

  Moreover, according to this invention, electrical connection of a some LED illumination board becomes easy with a feed wire.

  Further, according to the present invention, the fixing and electrical connection of the LED are simplified by using the electrically conductive layer.

  According to the present invention, since the electrical connector is fixed to the back wall of the mounting board, even if it is accommodated in the illumination housing, it does not impede light reflection.

  According to the present invention, the cost of the LED substrate can be reduced by using an inexpensive heat sink.

  According to the invention related to the LED lighting unit, since the board on which the LED is mounted can be attached by the locking means integrally formed with the bottom member, the LED can be easily attached. Also, the number of parts is reduced.

  According to the above invention, the central reflection portion is constituted by the small central reflection area directly above the LED and the central peripheral reflection area provided around the central reflection area, and the outer reflection portion is formed by the central peripheral reflection area. Since the plurality of openings having an opening area that increases in the radiation direction from the light source to the light emission direction, the light from the LED is used with high efficiency, and without increasing the thickness of the LED in the radiation direction. It is possible to obtain uniform illumination light over a wide area without leaving a bright spot in the upper portion and without darkening the upper portion.

  According to said invention, the light radiated | emitted from LED reflects in a housing and / or an optical reflecting plate at least once, and passes an opening. That is, the light emitted from the LED does not pass directly through the opening. Thereby, light can be utilized from LED with high efficiency by utilizing reflection.

  According to the invention relating to the LED illumination device described above, a large LED illumination device can be configured by connecting a plurality of LED illumination units.

FIG. 1 is a schematic top view of an LED substrate according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the LED substrate of FIG. FIG. 3 is an exploded view of the wiring board of FIG. FIG. 4 is an exploded perspective view of the LED lighting unit on which the LED substrate according to the embodiment of the present invention is mounted. FIG. 5 is a plan view of the optical reflector of FIG. 6A is a cross-sectional view taken along line VI-VI in FIG. 5, and FIG. 6B is an explanatory diagram for explaining the opening in FIG. FIG. 7 shows an LED lighting device configured by connecting a plurality of LED lighting units of FIG. 4, FIG. 7A is a top view, and FIG. 7B is a back view. FIG. 8 shows a conventional LED illumination substrate, FIG. 8 (a) is a schematic plan view, and FIG. 8 (b) is a side view.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the embodiment described below exemplifies an LED board for embodying the technical idea of the present invention, an LED lighting unit using the LED board, and an LED lighting device configured by connecting a plurality of the LED lighting units. However, it is not intended to limit the invention to these, but is equally applicable to other embodiments within the scope of the claims.

With reference to FIGS. 1-3, the LED board which concerns on embodiment of this invention is demonstrated. 1 is a schematic top view of an LED substrate according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the LED substrate of FIG. 1, and FIG. 3 is an exploded view of the wiring substrate of FIG.
As shown in FIGS. 1 and 2, the LED substrate 1 according to the embodiment of the present invention is mounted and fixed on the surface of the LED 2, the mounting substrate 3 on which the LED is mounted, and the mounting base. The wiring board 6 is thin and includes two electrical connectors 11 and 12 attached to the back wall of the mounting board 3.

As shown in FIG. 2, the LED 2 includes a metal base 2a and a single light-emitting diode or a group of light-emitting diodes fixed on the base (hereinafter collectively referred to as these). And a lens 2b covering the LED element, and terminals 2 ₁ and 2 ₂ derived from the LED element. This LED has a cathode heat dissipation type and an anode heat dissipation type, and both types can be used. When the anode heat radiation type is adopted, the heat radiation contact can be directly fixed to a mounting substrate described later. This LED 2 is called a surface mount type LED, and is very versatile and relatively inexpensive.

As shown in FIG. 2, the mounting board 3 includes a rectangular heat sink 4 having a predetermined thickness and size, and an electrically conductive layer 5 provided on the surface of the heat sink.
The heat radiating plate 4 has a rectangular shape having a pair of opposing sides 4a and 4b and other opposing sides 4c and 4d, and is formed of a plate material having a relatively large thickness. The heat radiating plate 4 is made of a relatively inexpensive material having a predetermined thermal conductivity and a heat radiating action, such as a metal material. The metal material is preferably conductive, but it is not always necessary to have conductivity. For example, an iron material or other materials may be used. When a copper material is used, it becomes expensive compared with iron, aluminum, etc., so inexpensive aluminum and aluminum alloy are preferable. In this embodiment, description will be made using aluminum or an aluminum alloy (hereinafter referred to as aluminum).
If the heat radiating plate 4 is formed of aluminum, the aluminum surface is oxidized, the electrical conductivity is poor, and it is difficult to fix the solder. Therefore, an electrically conductive layer 5 made of a material having good electrical conductivity, for example, a copper material, is formed on one surface of the heat radiating plate 4 made of aluminum. The electric conductive layer 5 is formed by a known method, for example, a composite plate in which a thin copper plate and aluminum are bonded together under high pressure, that is, a clad material, or a plating process. By providing the electric conductive layer 5, the LED 2 can be fixed to the electric conductive layer 5 with solder. Incidentally, the electric conductive layer 5, without providing on one surface entire surface of the heat sink 4, only the necessary areas such as electrical connections, for example, LED area 3A will be described later or, contact holes 3 ₃ this LED area 3A May be limited to the area 3AB (see FIG. 2). Thereby, the usage-amount of an expensive material can be reduced. Further, by providing the electrically conductive layer 5 in the LED area 3A, soldering with the bottom surface of the LED 2 becomes easy, and the LED 2 is directly fixed to the substrate, so that the heat from the LED 2 is efficiently transferred to the base material. To dissipate heat.

  As shown in FIG. 2, the mounting board 3 is partitioned into an LED area 3A on which the LED 2 is fixed and a board area 3B on which the wiring board 6 is placed and fixed. The LED area 3 </ b> A is divided into an area that is the same as or slightly wider than the size of the bottom surface of the LED 2.

The board area 3B is divided into substantially the same area as the wiring board 6, and through holes 3 through which the terminal pins 11a, 11b and 12a, 12b of the first and second electrical connectors 11, 12 are inserted at the four corners, respectively. ₁ , 3 ₂ and 3 ₃ , 3 ₄ are perforated. These through holes 3 ₁ , 3 ₂ and 3 ₄ are each provided with an insulating member on the inner wall so that the terminal pins 11 a, 11 b and 12 b do not come into electrical contact with the mounting substrate 3. In addition, without attaching an insulating member, it may be formed by a hole having a diameter larger than the thickness of each terminal pin 11a, 11b, and 12b so that each terminal pin does not come into electrical contact within the through hole.

As shown in FIG. 3, the wiring board 6 is formed of a rectangular and thin flexible board having a pair of opposing long sides and a pair of opposing short sides connecting these long side ends.
In this wiring board 6, a wiring pattern and land portions are formed of, for example, copper foil on a base film 7 made of polyimide or the like, and a cover film 10 made of similar polyimide or the like is laminated and bonded thereon. Formed by. The cover film 10 may not be provided. On the surface of the base film 7, two first and second wiring patterns 8 and 9 are arranged at predetermined intervals in the longitudinal direction.
The first wiring pattern 8 is provided with land portions 8a and 8b to which one terminal pins 11b and 12b of the first and second connectors 11 and 12 are inserted and fixed at both ends. In each land portion, insertion holes 8 ₁ and 8 ₁ through which the tips of the terminal pins 11b and 12b are inserted are formed. Terminal pins 11b and 12b are inserted into the land portions 8a and 8b, respectively, and are electrically connected by solder. The first wiring pattern 8 is a feed line that is electrically connected to a similar wiring pattern of another LED illumination board provided adjacently. The second wiring pattern 9 is arranged partway in parallel with the first wiring pattern 8, the land portion 9 a to which one terminal pin 11 a of the first connector 11 is fixed at one end, and the LED 2 at the other end. A land portion 9b to which one of the terminals is connected is provided. Insertion holes 9 ₁ is formed in the land portion 9a. A terminal pin 11a is inserted into the land portion 9a and is electrically connected by solder. One terminal of the LED 2 is electrically connected to the other land portion 9b by solder. Since the second wiring pattern 9 is electrically connected to one terminal of the LED 2, it is expressed as an LED connection line in the claims. The cover film 10 is formed with openings 10 ₁ and 10 ₂ each having a size that exposes each land portion at a location corresponding to each land 8a, 8b, 9a, and 9b. The wiring substrate 6 is formed by laminating a cover film 10 on a base fill 7 on which first and second wiring patterns 8 and 9 are disposed. By this bonding, the lands 8a, 8b, 9a, 9b of the wiring board 6 are exposed from the openings 10 ₁ , 10 ₂ of the cover film 10.

Assembly of LED substrate 1, first, preparing a mounting board 3, is fixed to LED2 with solder LED area 3A of the mounting substrate, and solder connection to one terminal _{2 1} of LED2 on the surface of the electrically conductive layer 5 . Next, the terminal pins 11a, 11b and 12a, 12b of the first and second connectors 11 and 12 are inserted into the through holes 3 ₁ , 3 ₂ and 3 ₃ , 3 ₄ of the mounting substrate 3, respectively. The connector is fixed to the back wall of the mounting board 3. Subsequently, the wiring board 6 is placed on the board area 3B. At this time, the insertion holes 8 ₁ , 9 ₁ and 8 ₁ , 9 ₂ of the wiring board 6 are inserted into the terminal pins 11a, 11b and 12a, 12b of the first and second connectors 11, 12, respectively. Thereby, among the plurality of terminal pins 11a, 11b, 12a, and 12b, the terminal pins 11a, 11b, and 12b can be brought into contact with the land portions 9a, 8a, and 8b of the wiring board 6, and the remaining terminals. The pin 12a can be in contact with the conductive layer 4. Thereafter, the solder with the solder connecting by injecting into the opening 10 ₁ of the wiring board, and soldered to the land portion 9b exposed the other terminal 2 ₂ LED2 from the opening 10 _2, completing the assembly.

  According to the LED substrate 1, a highly versatile and relatively inexpensive LED and an inexpensive heat sink can be used. Even if such an LED is used, the LED can be directly fixed to the mounting substrate, so that heat from the LED is efficiently transmitted to the heat radiating plate, and abnormal overheating of the LED can be prevented. Moreover, since the wiring board is used, an inexpensive metal material can be used without using an electrically conductive material for the heat sink, and the LED board can be manufactured at a low cost. Furthermore, since the electrical connector is fixed to the rear wall of the mounting board, even if it is accommodated in the lighting housing, it does not impair the light reflection.

  Although the LED substrate according to the embodiment has been described above, the present invention is not limited to this and can be variously changed. For example, the wiring board is provided with two wiring patterns, that is, an LED connection line and a feed line. However, only the LED connection line is provided on this wiring board, and the feed line is provided away from the LED board. Also good. Further, the through hole of the mounting substrate may be formed by a narrow groove. Furthermore, it may be connected by a lead wire without using an electrical connector.

With reference to FIGS. 4-7, the LED illumination unit and LED illumination apparatus using this LED substrate are demonstrated. FIG. 4 is an exploded perspective view of the LED lighting unit according to the embodiment of the present invention.
As shown in FIG. 4, the LED lighting unit 13 according to the embodiment of the present invention includes an LED substrate 1 on which the LED 2 is mounted, and a through-opening where the upper portion is open and the light emitting portion of the LED 2 is exposed at a substantially central portion of the bottom portion 14 b. It includes a housing 14 of the flat box-type having a hole 14 _1, and an optical reflector plate 15 to uniformly illuminate the light from LED2 block the opening of the housing, the optical reflector plate 15, a predetermined opening edge of the housing 14 It is configured to be fixed with a gap.

  The housing 14 includes a square base plate 14b having the same length on one side, and side plates 14c to 14f erected at a predetermined height substantially perpendicular to the peripheral edge of the base plate, and the side plates 14c to 14f. Is formed of a flat box-shaped body having an opening 14a above. The housing 14 has a high light reflectance, and is formed of a material having a low light transmittance and a low light absorption rate, for example, an ultrafine foamed light reflecting plate. Note that this ultrafine foamed light reflecting plate has a reflectance of 98%, a light transmittance of 1%, and a light absorption of 1%. As other materials, titanium white fine particles emulsified or polytetrafluoroethylene fine particles emulsified may be used. These materials may be provided on the housing by coating or screen printing.

The bottom plate 14b, the through-hole 14 ₁ is drilled for the light emitting portion of the LED2 is exposed to the substantially central portion. Further, the bottom plate 14b is around the through-hole 14 ₁ of the rear wall, a plurality of fixing portions 14 ₂ that are mounted substrate 3 is fixed is provided. The fixed portion 14 _2, preferably forms part of the bottom plate 14b in the cut and raised the cut-and-raised claws into a predetermined shape. By using the raised and raised claws, the mounting substrate 3 can be easily attached manually without using a tool. Of course, it can be easily removed.

The peripheral edge of the opening 14a of the housing 14, that is, each top side of the four side plates 14c to 14f is a flat side, and a plurality of the flat sides projecting upward from these flat sides, this embodiment Then, the three locking claws are arranged at a position having a predetermined regularity. That is, the opposite side plates 14c, 14d are in top edge of the side plate 14c, the locking claws 14 N in the central portion of the top _side, the locking claw of the right and left apart different distances on both sides of the locking claws 14 _N 14 _L , 14 _R are formed, and the left and right protruding claws 14 _{L ′} , 14 are formed on the top side of the other side plate 14 d, the protruding claws 14 _{N at} the center of the top side, and different distances on both sides of the protruding claws 14 _{N. R ′} is formed, and the left and right protruding claws 14 _L , 14 _R and 14 _{L ′} , 14 _{R ′} facing the both side plates 14 e, 14 f are arranged at positions separated by a predetermined distance. That is, the Hidarigakaritometsume 14 _L and 14 _{L ',} are separated by the same distance (offset). The other right protrusion claws 14 _R and 14 _{R ′} are also displaced by the same distance. In addition, the left and right protruding claws 14 _L and 14 _R and 14 _{L ′} and 14 _{R ′,} which are also opposed to the other opposing side plates 14 e and 14 f, are arranged at positions separated by a predetermined distance. Since these protruding claws 14 _{L ′} and 14 _{R ′} are displaced by a predetermined distance, they are arranged with regularity. In this embodiment, there are three locking claws, but the number is not limited to this.

  The locking claws of the side plates 14c to 14f all have the same shape. The projecting claw has a base portion erected upward with a predetermined width from the top side, a columnar portion erected upward at a predetermined width length from the top of the base portion, and And a collar part above the columnar part. The protrusion claw has a stepped portion (hereinafter also referred to as a shoulder portion) at the connecting portion between the base portion and the columnar portion, and when the optical reflecting plate 15 is attached to the housing 14, the back surface of the optical reflecting plate 15 is provided. Is supported on the shoulder, and a gap in the height of the base portion is formed between the peripheral edge of the opening 14a of the housing 14, that is, between the top sides of the four side plates 14c to 14f and the back surface of the optical reflecting plate 15. Is formed. This gap serves as a light passage (leakage passage) through which light from the LED 2 passes (leaks), and this light passage prevents light from reaching the opening edge portion of the housing 14 from being blocked and darkening. it can. This light passage can be made to be uniform illumination without darkening the connection location when a plurality of LED illumination units are connected to produce a surface illumination device. Further, the height of the columnar portion is the thickness of the optical reflecting plate 15. Further, the collar portion is locked in the engaging groove of the optical reflecting plate 15.

Next, the optical reflector will be described with reference to FIG. 5 is a plan view of the optical reflector in FIG. 4, FIG. 6A is a cross-sectional view taken along the line VI-VI in FIG. 5, and FIG. 6B is an explanatory view for explaining the opening in FIG.
As shown in FIG. 5, the optical reflecting plate 15 is formed of a regular tetragonal plate body having a predetermined thickness and one side having the same length. That is, the opposing sides 15c, 15d and 15e, 15f have the same length. The length of the optical reflector 15 is the same as the length of the housing 14. Its thickness is t. The optical reflection plate 15 has the same high light reflectance as the material of the housing 14 and is formed of a material having a low light transmittance and a low light absorption rate, such as an ultrafine foamed light reflection plate. By constructing the housing and optical reflector with materials with high light reflectance, low light transmittance and low light absorption, light loss from the light source is reduced, and multiple reflection of light between the housing and the optical reflector is high. It is done with efficiency and light utilization is increased.

The optical reflecting plate 15 includes four sides 15c to 15f that engage with the engaging claws of the housing 14, a central reflecting portion 17A at the center, and an external reflecting portion 17B at the outer periphery of the central reflecting portion. And are provided. The optical reflector 15, a tool insertion hole 15 ₀ can be inserted a tool (screwdriver) to screw the housing 14 to the support member at four corners are formed.
Engaging groove four sides 15c~15f _has become a _{15 L, 15 N, 15 R} , 15 L and _{', 15 N, 15 R'} . These engaging grooves are respectively engaged with the projecting claws 14 _L , 14 _N and 14 _R of the housing 14 and 14 _{L ′} , 14 _N and 14 _{R ′} . Since the optical reflector 15 is attached to the housing 14 by the engagement between the engaging claws and the engaging groove, the optical reflector 15 is securely attached to the normal position. As a result, the optical reflector 15 is accurately positioned and properly mounted, and mounting other than this normal mounting, for example, mounting with the front and back sides upside down, or assembling and coupling with different right and left front and back cannot be performed. In this embodiment, the engaging groove is provided on the optical reflecting plate and the locking claw is provided on the housing. However, on the contrary, the engaging groove may be provided on the housing and the locking claw is provided on the optical reflecting plate. The engaging groove and the locking claw may be mixed and provided on the housing or the optical reflector.

  The central reflecting portion 17A is located at a position directly above the LED 2 when the optical reflecting plate 15 is attached to the opening 14a of the housing 14, and a central reflecting area with a small area at a position facing the vertically upper portion of the light emitting portion. 17a and an area within a predetermined distance from the center centered on the central reflection area, that is, a central peripheral reflection area 17b. From the spectral curve, the LED 2 is irradiated with the strongest light on the central reflection region 17a, and then the next strongest light is irradiated on the central peripheral reflection area 17b. Therefore, the central reflection area 17a is designed so that the light transmittance is low and the light reflectance is high. This design includes selection of the optical reflector material, processing of this material (eg, formation of a half groove, adjustment of the plate thickness), and the like. The central peripheral reflection area 17b is designed to transmit a part of light while increasing the light reflectance next to the central reflection area 17a. The transmission of light is a small hole, a slit, a narrow groove, or the like. In the case of a small hole, since the area of the central reflecting portion 17A is small, the pitch is smaller than, for example, half the pitch of the openings 18 described later. Further, as shown in FIG. 5, the small holes in the central peripheral reflection area 17b are arranged at equal intervals in a lattice pattern, and the small holes are formed at the boundary corners so that the central reflection area 17a is substantially circular. On the other hand, the opening of the outer reflecting portion 17B is made into this small hole. Thereby, the central reflecting portion 17A can obtain uniform illumination light without leaving a bright spot and conversely without darkening the portion directly above.

The external reflection portion 17B has a plurality of openings 18 _{1 to} 18i to 18 _N (hereinafter referred to as “this”) arranged with a predetermined regularity from the central peripheral reflection area 17b of the central reflection portion 17A toward the sides 15c to 15f. A general term for the opening is indicated by reference numeral 18). The opening 18 is a through-hole opening that penetrates the outer reflecting portion 17B. That is, this opening is a reflection surface and a radiation surface. In the state shown in FIG. 5, a plurality of these openings 18 are arranged in parallel with each other at a predetermined interval between a parallel line parallel to the side 15c and a vertical line parallel to the side 15e perpendicular to the side 15c. And each parallel line is formed at a crossing point. This interval is the same. Therefore, the plurality of openings 18 are arranged with regularity in a matrix (lattice) pattern at equal intervals. In the regular arrangement, there is also a so-called stacking arrangement in which the second stage openings are positioned between the first stage openings. Edge openings can be arranged uniformly.
In this embodiment, the intervals are the same, but may be different. These openings 18 are circular holes having a predetermined diameter, and the size of the openings 18 is set so that the diameter increases as the distance from the central reflecting portion increases. That is, for these openings 18, the ratio of the total area of the openings to a preset reference area is defined as an opening ratio A (area of the openings 18 in the predetermined portion / reference area), b and c are constants, and x (mm) ( Assuming that the minimum distance from the center of the radiation surface of the optical reflector 5 facing the LED 2 to the opening 18 along the radiation surface is approximately A = bx ² + c
It is formed to have the relationship of That is, the aperture ratio A increases in proportion to the square of the distance as the distance from the center O of the radiation surface 15a of the optical reflecting plate 5 facing the LED 2 increases outward along the radiation surface 15a.

  The through hole having the opening 18 is preferably an inclined hole in which the opening on the radiation surface side is unevenly distributed toward the central reflecting portion 17A side and the opening on the reflecting surface side is unevenly distributed in a direction away from the central reflecting portion side. In addition, it is preferable that the through hole has a gentle slope as it goes from the reflection area around the center toward the radial direction. By making the through hole into an inclined hole, the light from the LED is reflected at least once in the housing 14 and / or after being reflected by the optical reflector 15 and then directly irradiated from the opening. Disappears.

As shown in FIG. 6B, this is a so-called quadratic curve when the distance x is on the horizontal axis and the aperture ratio A is on the vertical axis. The aperture ratio A = 1 means a fully open state.
In FIG. 6B, in this embodiment, b = 0.000375, and the constant c is, for example, a non-through hole at the center O of the radiation surface 15a of the optical reflector 15 facing the LED 2, for example. For example, c = 0.04 is set. As a result, the aperture ratio A = 0.04 at the point where x = 0.

  The optical reflector 5 is formed so that the light from the LED 2 does not pass through the opening 18 directly. That is, the light from the LED is formed to pass through the opening 18 after being reflected at least once in the housing 14 and / or by the optical reflector 15. Specifically, the size of the opening 18 is formed so as to satisfy the following condition. That is, the minimum distance from the center of the radiation surface of the optical reflector 5 facing the LED 2 to the opening 18 along the radiation surface is x, the distance in the radiation direction from the LED 2 to the optical reflector 15 is d, and the diameter of the opening 18. Where a is the thickness of the outer reflection portion 17B and t is the thickness of the outer reflection portion 17B, these relationships are set to d / x <t / a. This prevents light emitted from the LED 2 from passing directly through the opening 18, and the light from the light source passes through the opening 18 after being reflected at least once in the housing 14 and / or by the optical reflector 15. Only the reflected light, that is, the reflected light is allowed to pass. Thereby, the light (reflected light) that has passed through the outer reflecting portion 17B has a uniform light distribution at a position away from the optical reflecting plate by a predetermined distance. That is, the light emitted from the light source is configured not to pass directly from the opening. Thereby, uniform illumination light can be obtained. Moreover, the light from a light source can be utilized with high efficiency by utilizing reflection. If the light emitted from the light source passes directly through the opening 18, the light flux that has passed through the optical reflecting plate 15 is too strong, so that the light is emitted from the optical reflecting plate 15 at a position separated by a predetermined distance in the light emission direction. It is difficult to make the light distribution uniform.

  In this embodiment, the opening is a circular hole, but other shapes such as a triangle, a quadrangle, a star, or various character shapes may be used. Regardless of the shape, the desired purpose can be achieved if the above conditions are satisfied. In addition, when the opening has various character shapes, the design is improved.

As described above, the LED lighting unit 13 according to the embodiment of the present invention has been described. However, by preparing a plurality of the LED lighting units and connecting them, a desired large-sized LED lighting device can be manufactured.
FIG. 7 shows an LED lighting device. This LED illumination device 10 is a unit in which three LED illumination units 13A to 13C are connected. In these connections, a support member is provided on the back surface of each LED lighting unit 13A to 13C, a tool is inserted from a tool insertion hole of each LED lighting unit, and each housing is fixed to the support member. On the other hand, each LED illumination unit 13A-13C is connected by the connector by which the electrical connector fixed to the back wall was connected to the lead wires L1 and L2, respectively.

DESCRIPTION OF SYMBOLS 1 LED board, 2 LED, 3 mounting board, 4 heat sink, 5 electrically conductive layer, 6 wiring board, 7 base film, 8 feed line, 9 LED connection line, 10 cover film, 11, 12 electrical connector, 13, 13A ˜13C LED illumination unit, 14 housing, 15 optical reflector, 17A central reflector, 17B outward reflector, 18, 18 ₁ -18i-18N _N opening

Claims (10)

A light emitting diode (hereinafter referred to as LED), a mounting board on which the LED is mounted, and a wiring board disposed on the mounting board surface;
The mounting board is made of a heat sink having a predetermined thickness and area, and the wiring board is made of an insulating sheet provided with LED connection lines,
The mounting board includes a first area and a second area having a predetermined area on one side of the heat sink, and the wiring board is disposed in one of the first and second areas. An electrically conductive layer is provided in the area, and the LED is directly fixed to the electrically conductive layer or an empty space by a heat dissipation surface, one terminal of the LED is connected to the LED connection line, and the other terminal is the electrically conductive layer. Each connected to
The wiring board is provided with a feed line connected in series to another LED lighting board connected to the wiring board,
The LED connection line and the feed line of the wiring board are provided with wiring terminals connected to external wiring at the end of each wiring,
The mounting board is formed with a through hole or a narrow groove penetrating the mounting board at a position corresponding to the wiring terminal of the wiring board, and a through hole or a surface located on a surface opposite to the surface on which the wiring board is disposed. An LED substrate , wherein an electrical connector is attached to a portion surrounding the narrow groove . 2. The LED substrate according to claim 1, wherein the electrical conductive layer is provided on the entire surface of the heat radiating plate, and the wiring substrate and the LED are provided on the electrical conductive layer. The heat sink, aluminum, LED substrate according to claim 1 or 2, wherein the electrically conductive layer is characterized in that it is formed of a metal material such as copper or gold. An LED, a housing in which the LED is mounted on the bottom and having an opening and an inner wall surface formed of a reflective material, and an optical reflector that covers the opening of the housing and has a high reflectivity;
The optical reflection plate has a central reflection part having a predetermined area directly above the LED and an outer reflection part around the central reflection part. The housing has a light emitting part of the LED at the bottom. The LED substrate according to any one of claims 1 to 3 , wherein a locking means that is integrally formed with the bottom member is provided on an exposure hole to be exposed and a bottom back wall in the vicinity of the periphery of the exposure hole, and the LED board according to any one of claims 1 to 3. An LED lighting unit that is fixed. The central reflection portion is provided directly above the LED, and has a small central reflection area with low light transmittance and high light reflectance, and a central peripheral reflection with low light transmittance provided around the central reflection area. The outer reflection portion is formed of a plurality of through holes through which reflected light having an opening area that increases in the radial direction from the central peripheral reflection area toward the radial direction. Item 5. The LED illumination unit according to Item 4 . X is the minimum distance from the center of the radiation surface of the optical reflector facing the LED to the opening along the radiation surface, d is the distance in the radial direction from the LED to the optical reflector, and When the opening dimension is a and the thickness of the outer reflection part is t,
d / x <t / a
The LED lighting unit according to claim 4 , wherein: The through hole has the openings on the reflection surface and the radiation surface of the outer reflection portion, the opening on the radiation surface side toward the central reflection portion side, and the opening on the reflection surface side away from the central reflection portion side. LED lighting unit according to claim 5 or 6, characterized in that it is formed in the inclined hole which is eccentrically distributed to. The LED illumination unit according to claim 7 , wherein the through hole has a gradually inclined slope from the center peripheral reflection area toward a radial direction. The ratio of the area sum of the openings to a preset reference area is defined as an aperture ratio A (the area of the opening of the predetermined portion / reference area)
When b and c are constants and x is the minimum distance from the center of the radiation surface of the optical reflector facing the LED to the opening along the radiation surface, approximately A = bx ² + c
The LED lighting unit according to claim 4 , wherein: An LED lighting apparatus comprising a plurality of the LED lighting units according to claim 4 .

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