JP2013118285A - Light emitting diode module and lighting apparatus using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting diode module for lighting capable of securing a degree of freedom in a wiring work and a design of a lighting apparatus, and a lighting apparatus using the same.SOLUTION: A light emitting diode module in which a plurality of light emitting diode chips 200 are mounted on a mounting surface 110 of a rectangular plate shaped substrate 100 with a good thermal conductivity, comprises a substrate formed of a member superior in thermal conductivity and having its outline in nearly rectangular shape. An element mounting surface with a predetermined shape is formed on a surface of the substrate, and an insulating layer is formed around it. The plurality of light emitting diode chips are regularly arranged along a direction orthogonal to each other on the element mounting surface of the substrate, positive and negative electrodes 131, 132 for supplying power to the plurality of light emitting diode chips are formed on the insulating layer of the substrate, and a plurality of positive and negative electrodes are formed on the insulating layer, respectively.

Description

  The present invention relates to a light emitting diode module.

  In recent years, there has been a significant flow of energy saving (hereinafter simply referred to as “energy saving”) in home appliances. Among them, for home lighting fixtures, for example, instead of conventional incandescent amplifiers, light sources with lower power consumption are used. The LED lighting fixtures used (for example, Patent Documents 1 and 2 below) have been widely used.

  More specifically, instead of a conventional incandescent amplifier, a light bulb type lamp (for example, Patent Document 3 below) having a fluorescent lamp as a light source and having the same appearance as a conventional incandescent amplifier has been developed. And it has been widely put into practical use. Further, a lighting fixture (for example, Patent Document 4 below) that obtains a desired light distribution using a light emitting diode module (hereinafter referred to as an LED module) in which a plurality of LEDs having high luminance are arranged on a reflector is already known. Yes.

JP 2003-59330 A JP 2003-59332 A JP 2009-170114 A JP 2010-157391 A

  As described above, in a lighting fixture using LEDs, generally, an LED module in which a plurality of LEDs are arranged on a reflecting plate is used, and the LED module is appropriately arranged in the casing of the lighting fixture. By doing so, it was already known to obtain a desired light distribution. However, with regard to so-called LEDs (light emitting diodes), which are light emitters arranged in the LED module, various considerations have been made for the structure for taking out the heat generation and the wiring structure, but the LED elements. No consideration was given to the electrode arrangement.

  Therefore, in the present invention, as will be described in detail below, by improving the arrangement structure of the plurality of LED elements on the reflective substrate, more efficient luminance (higher luminance for a certain input power is obtained). A light-emitting diode module having a structure capable of securing a larger (wider) degree of freedom in wiring work and design of a lighting fixture, and further utilizing the light-emitting diode module for lighting It is an object of the present invention to provide a luminaire.

  In order to achieve the above-described object, according to the present invention, first, a light emitting diode module in which a plurality of light emitting diode chips are mounted on a mounting surface of a rectangular plate-shaped substrate having excellent thermal conductivity, which has excellent heat conductivity. And an element mounting surface having a predetermined shape and an insulating layer formed around the element mounting surface on one surface of the substrate, and mounting the element on the substrate. On the surface, the plurality of light emitting diode chips are regularly arranged along a direction perpendicular to each other, and power is applied to the plurality of light emitting diode chips on the insulating layer of the substrate. There are provided positive and negative electrodes for supply, and a plurality of the positive and negative electrodes are provided on the insulating layer, respectively.

  In the present invention, in the light emitting diode module described above, a frame-shaped dam member is formed around the plurality of light emitting diode chips, and a fluorescent layer is formed inside the dam member. Each of the plurality of positive and negative electrodes formed is preferably formed outside the dam member. Further, the plurality of positive and negative electrodes formed is symmetric with respect to the center line of the module, and It is preferable that the outer shape is formed so as to be unevenly distributed in the vicinity of the one side along one side of the substantially rectangular substrate and two sides adjacent thereto.

  Further, according to the present invention, in order to achieve the above-described object, a base part, and an outer frame member in which the base part is screwed and attached to a part thereof, and a radiator is attached to the inside thereof. A lighting fixture including a light diffusing portion provided so as to cover the outer frame member is provided with the above-described light emitting diode module mounted on the upper surface of the radiator.

  In the present invention, in the lighting fixture described above, the light emitting diode module is preferably fixed using a frame-shaped mounting member, and further, the light emitting diode module is pressure-mounted. It is preferable that the radiator is thermally connected to a base on the negative electrode side of the base part.

  According to the present invention described above, it is possible to extract light more efficiently from the LED, which is a light emitting element, and in particular, it is possible to obtain white light with high efficiency by using a high-power blue light emitting diode. In addition to being able to provide a practical and excellent light emitting diode module, it is also possible to provide a light emitting diode module having a structure capable of ensuring a greater (wider) degree of freedom in wiring work and lighting design. In addition, an excellent effect of providing a lighting apparatus using the same is exhibited.

It is a perspective view which shows the whole structure of the light emitting diode module which becomes one Example of this invention. It is II-II sectional drawing in the light emitting diode module of the said FIG. It is a partially expanded perspective view for demonstrating the space | interval of the adjacent chip | tip in the said light emitting diode module. It is a figure including the graph for showing the relationship between the space | interval of the adjacent chip | tip in the said light emitting diode module, and the light quantity obtained. It is a partially expanded sectional view for demonstrating the relationship between the surface shape of the dam (dam member) and fluorescent layer in the said light emitting diode module. It is a figure containing the graph which shows the example about the component of the fluorescent layer in the said light emitting diode module. It is a perspective view for demonstrating the electrode structure of the said light emitting diode module. It is an expansion | deployment perspective view containing the partial cross section which shows the structure of the lightbulb type lighting fixture using the said light emitting diode module. It is a top view for showing the mounting structure of the light emitting diode module. It is a partially expanded sectional view which shows the attachment structure of the said light emitting diode module.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  First, the attached FIG. 1 and FIG. 2 (FIG. 1 is a perspective view of a light emitting diode module and FIG. 2 is a sectional view taken along the line II-II) show a light emitting diode module according to an embodiment of the present invention. In these drawings, reference numeral 100 indicates a plate-like substrate (hereinafter referred to as “aluminum substrate”) made of aluminum, which is a metal having excellent thermal conductivity, and has a central portion at the center. A device mounting surface 110 for arranging and mounting a plurality of light emitting diode devices (also referred to as “LED chips”), which will be described below, is provided. The element mounting surface 110 has a mirror-finished surface. The substrate is formed in a concave shape. A so-called dam (weir member) 120 made of a white member made of, for example, a silicon-based resin material is formed around the element mounting surface 110. For example, the dam 120 is directly applied by moving the tip of the nozzle along the periphery on the insulating film 130 (described later) while discharging the resin member from the nozzle, and then heated. It is formed by thermally curing the resin member.

  In addition, an insulating film 130 is formed on the remaining surface of the aluminum substrate 100 surface, that is, outside the element mounting surface 110, and a positive electrode 131 and a negative electrode 132 are formed on a part thereof. Each is formed in pairs (two). Further, a pair of linear bonding pads 133 and 134 are formed along the opposite sides of the mounting surface 110 (laterally). As is apparent from the drawing, a plurality (80 in this example) of LED chips 200 are regularly (bonding pads 133 and 134 formed in this example) on the element mounting surface 110. 10 LED chips are arranged in series at equal intervals along one side that is different from the side (in the vertical direction) (for one row), and it is placed along the other side (in the horizontal direction) 8) Eight rows are arranged in parallel electrically. Reference numeral 135 in the figure denotes, for example, an Au wire (bonding wire) for electrically connecting the bonding pads 133 and 134 and a plurality of LED chips arranged therebetween. Show. Reference numeral 136 is a so-called anode display mark. In addition, the alignment recognition mark used when mounting a part by an automatic mounting machine is provided with a cross mark on one side where no electrode is provided (not shown).

Further, in this light emitting diode module, a fluorescent material is formed by injecting a silicon resin material mixed with a powdered phosphor into the dam (weir member) 120 described above and then heating (thermosetting) it. A layer 300 is provided. That is, a part of the light emitted from the plurality of LED chips 200 is reflected by the mirror-finished element mounting surface 110 and then light having a desired wavelength (for example, white) by the phosphor in the phosphor layer 300. Light) and output as illumination light from the light emitting diode module.
<LED chip arrangement interval>
According to various examinations and experiments conducted by the present inventors, the plurality of LED chips 200 (each 0.2 W) disposed on the element mounting surface 110 of the aluminum substrate 100 are laterally (ie, If the distance between adjacent chips in the same direction as the side where the bonding pads 133 and 134 are formed is too narrow, the amount of light obtained from these LED chips decreases. This is presumably because if the distance between the chips is too narrow, the light from the adjacent chip enters the other chip without being sufficiently reflected by the mirror surface or the like.

  Therefore, the present inventors have observed the amount of light obtained from the plurality of LED chips 200 by changing the interval between adjacent chips 200. Here, as shown in FIG. 3 attached, the interval between adjacent chips 200 is “d”, the vertical length of the LED chip is “l”, and the length l of the LED chip is 1 The ratio of the distance d between the LED chip and the adjacent LED chip is expressed as “d / l”. The amount of light obtained is shown as an efficiency with the amount of light when the ratio “d / l” = 1.50 as a reference (100%). The results are shown in the graph of FIG. 4 together with the following table. In addition, the dimension of the LED chip used at this time is 0.5 mm in length and 0.3 mm in width. Compared with these, the thickness is the adhesive layer on the lower surface (indicated by reference numeral 201 in FIG. 3). Even if it combined, it was only about 0.15 mm.

  As is clear from these tables and graphs, the smaller the “d / l” (that is, the smaller the distance between adjacent chips 200), the smaller the amount of light obtained, and conversely, the larger “d / l”. It can be seen that the amount of light obtained increases as the distance between adjacent chips 200 increases (however, the amount of light obtained saturates as “d / l” increases). On the other hand, in the light emitting diode module, the distance between adjacent chips is limited due to the number of chips determined from the necessary light emission amount. For these reasons, “d / l” between adjacent chips 200 is set to a value that is about 2 to 3.5 (range in which “efficiency” is about 70% to 80% of the saturation value). It turns out that is preferable. That is, according to this, the light emission efficiency obtained from one light emitting diode module can be further improved, and further, the heat generation from the LED is reduced to suppress the temperature rise, thereby extending the life of the LED. Can also be achieved.

  In the above description, the interval between chips adjacent to each other in the horizontal direction (that is, the same direction as the side where the bonding pads 133 and 134 are formed) has been described. However, in the present invention, it is further described in the vertical direction (that is, bonding). The same applies to the interval between chips adjacent to each other in a direction different from the side where the pads 133 and 134 are formed. According to this, the luminous efficiency of the light emitting diode module can be improved, and further, the LED Contributes to longer life.

In addition, by setting the interval between adjacent chips to a value that is about 2 to 3.5 in the ratio to the chip size as described above, the LED chip 200 is mounted on the element of the aluminum substrate 100. It is possible to prevent the resin material to be applied when mounting on the surface 110 from coming into contact with the resin material of the adjacent chip, and further from contacting and connecting. According to this, since the resin material to be connected covers the element mounting surface, it is possible to prevent reflection of light emitted from the LED chip 200, thereby improving the light emission efficiency of the light emitting diode module. Contributes to a longer life of the LED.
<Dam (weir member) and phosphor layer>
As described above, the dam 120 is formed by applying the resin member by moving the tip of the nozzle to the periphery of the element mounting surface 110 while discharging the resin member, and then heating and thermosetting the resin member. Yes. Therefore, as is clear from FIG. 2 above, it has a substantially semicircular cross section. In the above-described light emitting diode module, the portion surrounded by the dam (weir member) 120 is formed by injecting a silicon resin material mixed with powdered phosphor and then heating (thermosetting) it. A fluorescent layer 300 is provided.

  The height of the fluorescent layer 300 formed using the dam 120 described above is preferably uniform over the entire surface. For this purpose, the LED chip 200 mounted on the element mounting surface 110 of the aluminum substrate 100 is used. The ratio (h2 / h1) of the height h2 of the fluorescent layer 300 to the height (chip thickness h1) (chip thickness h1 = about 0.15 mm including the adhesive layer on the lower surface) is, for example, about 6 to 8 times It is preferable to set it, more preferably 6.7 times. Further, the ratio (h3 / h2) of the height (dam thickness h3) of the dam (dam member) 120 to the height h2 of the fluorescent layer 300 is set to about 70 to 75%, particularly preferably 73%. Is done. That is, according to this, the rise due to the viscosity of the resin material due to the chip thickness of the LED chip 200 located at the bottom of the silicon resin material can be reduced, and in this example, ± 10% of the desired thickness. Flatness could be secured.

  In addition, the fluorescent layer 300 formed by pouring and heating (thermosetting) the portion surrounded by the dam (weir member) 120 shrinks in volume especially during cooling after the pouring and heating. For this reason, it was difficult to ensure and maintain the flatness of the surface. That is, as shown in the attached FIG. 5, the resin expands and becomes convex when heated (see the broken line in FIG. 5), but its volume shrinks due to subsequent cooling. At this time, the height (thickness) of the resin at the contact portion with the dam 120 is large and the height (thickness) of the central portion is small, that is, deformed into a concave shape due to surface tension (two points in FIG. 5). See chain line).

  Therefore, in the light-emitting diode module according to the present invention, the silicon resin material to be injected into the portion surrounded by the dam 120 is injected to such an extent that the surface becomes almost flat due to contraction of the volume during cooling (solid line in FIG. 5). See). The injection amount of the silicon resin material can be determined by confirming in advance by experiments.

  Further, in the fluorescent layer 300 formed in the portion surrounded by the dam 120 as described above, the height (thickness) is set to a relatively large value in order to ensure a desired flatness. . However, in that case, the phosphor mixed in the silicon resin material is separated from the resin by, for example, precipitation, and the phosphor is not uniformly dispersed as a whole. Therefore, in this example, in order to solve such a problem, a powdery glass filler was mixed into the silicon resin material together with the powdered phosphor.

  More specifically, as the LED chip 200 constituting the light emitting diode module, a so-called blue light emitting diode that outputs light with a wavelength of approximately 460 nm (blue light) with high efficiency is adopted, and the blue light from the light emitting diode is also used. In order to convert light into white light (a part of blue light is converted into yellow light or red light), phosphor powder, further glass filler, for example, attached FIGS. 6 (a) and 6 (b) It was mixed in the ratio as shown in the graph (indicated as filler in the figure). And about the glass filler to mix, the higher light quantity was able to be obtained especially by employ | adopting a thing with an average particle diameter of 0.5 micrometer. The particle size of the phosphor at this time was approximately 9 to 21 μm. This is considered to be a result of the phosphor being uniformly dispersed as a whole by suppressing the phosphor mixed in the silicon resin material from being precipitated due to the mixing of the glass filler having such a particle size. 6A shows the case where two types of phosphors are used, and FIG. 6B shows the case where three types of phosphors are used.

In addition, in spite of the various measures described above, in the actually manufactured light-emitting diode module, the fluorescent layer 300 formed in the portion surrounded by the dam 120 is particularly the end portion, that is, the dam. In the vicinity of 120, the surface tends to be a curved surface (for example, refer to the surface shown by the broken line or the two-dot chain line in FIG. 5). Therefore, the LED chip 200 disposed on the element mounting surface 110 of the aluminum substrate 100 and inside the portion surrounded by the dam 120 is disposed with a sufficient distance from the dam 120. It is preferable. In this example, they are arranged at a distance (for example, 0.48 mm) sufficiently larger than the interval between adjacent chips (ratio to the chip size: 2 to 3.5). According to this, among a plurality (80 in this example) of LED chips 200 dispersed in a plane, the light is emitted from the chip located at the end, that is, adjacent to the dam 120. The emitted light is also sufficiently converted into white light, and output is refracted by the curved surface formed at the end of the fluorescent layer 300 (in the vicinity of the dam 120).
<Aluminum substrate and its electrode>
As described above, in the light emitting diode module according to the present embodiment, the insulating film 130 is formed on the outer peripheral side of the element mounting surface 110 formed on the surface of the substantially rectangular aluminum substrate 100, and the In part, a positive electrode 131 and a negative electrode 132 are formed in pairs (two). More specifically, these electrodes are made of Au and arranged symmetrically with respect to the center line of the module (see the broken line CC in FIG. 1), with one side as the positive electrode, The other side is formed as a negative electrode, that is, positive electrodes 131-1 and 131-2 and negative electrodes 132-1 and 132-2 are formed. The positive electrodes 131-1 and 131-2 are electrically connected to one bonding pad 133, the negative electrodes 132-1 and 132-2, and the other bonding pad 134, respectively. Yes. According to such an electrode structure, when the light emitting diode module is arranged in the lighting fixture and wiring is performed, the degree of freedom of the position of the wiring guided from the outside and connected to the electrode is ensured more (wide). It becomes possible.

  For example, as shown in FIG. 7 attached, it is possible to perform electrical connection (connection work by a robot or the like) more reliably by using an electrode at a position closer to the wirings 401 and 402 from the outside. . In other words, it is possible to secure a greater degree of freedom when designing a lighting fixture that employs the light emitting diode module as a light source.

  Moreover, in this example, these electrodes are provided centering on one side (unevenly distributed) in the direction of the center line. This is because, in order to fix the light emitting diode module according to the present embodiment to the surface of the radiator, a surface portion where the electrode is not formed (however, outside the dam (weir member) 120) is used.

  Hereinafter, as an example, a module fixing structure when the light-emitting diode module according to the present embodiment is used as a light source of a light bulb-type lighting fixture will be described with reference to FIG. In the light emitting diode module, since a large number (80 in this example) of LED chips 200 are mounted on the element mounting surface 110, the heat generation is also prevented in order to prevent a decrease in the light emitting efficiency of the element due to a high temperature. It is necessary to escape to the outside. Therefore, as described above, the module substrate is formed as a plate-like member made of aluminum, which is a metal having excellent thermal conductivity, that is, the aluminum substrate 100. And the said aluminum substrate 100 is connected to the heat radiator 13 of the lighting fixture formed from the metal excellent also in heat conductivity. More specifically, a member that forms a thermal resistance such as an adhesive cannot be interposed. Therefore, a structure in which the back surface of the aluminum substrate is fixed in a state where it is pressed against a radiator is generally used. Has been adopted.

  FIG. 8 is a perspective view of a light bulb-type lighting fixture, and in particular, is a partially developed view mainly showing the mounting structure of the light emitting diode module. In the figure, reference numeral 10 denotes an outer frame member that is formed in a conical shape having a cavity formed therein and gradually decreasing in diameter from the upper part toward the lower part.

  For example, a globe 20 formed in a substantially spherical shape by a semi-translucent member is attached to the upper part of the outer frame member 10, and on the other hand, a base part 11 constituting a positive electrode and a negative (grounding) are attached to the lower part thereof. ) A base 12 constituting an electrode is provided. In addition, a heat dissipating body (member) 13 having a circular substrate mounting surface extending in parallel is provided in the center of the opening of the outer frame member, and the above-described light emitting diode module has a heat transfer function. The heat radiating member 13 is fixed to the substrate mounting disk surface via the sheath 60. The heat transfer sheet 60 is formed of a sheet-like material having good thermal conductivity and high electrical insulation, such as silicone rubber. The heat radiating member 13 is made of, for example, a metal material having excellent thermal conductivity, such as aluminum, and is connected to the base portion 12 constituting the negative (grounded) electrode described above. That is, the heat generated in the light emitting diode module is transmitted from the light emitting diode module as a heat source to the aluminum substrate 100 and the heat radiating body 14, and further from the outer member 10 to the outside air, and from the outer member to the base 12. A broken line portion indicated by reference numeral 30 in the figure includes a voltage source and a so-called circuit portion including a lighting drive circuit and a control circuit for driving the light emitting diode module. The part to be done is shown. Instead of the heat transfer sheet 60, grease having good thermal conductivity and high electrical insulation may be used. Further, reference numeral 35 in FIG. 8 denotes a power circuit board. Reference numeral 39 denotes a resin storage case for storing the power circuit board 35. Reference numeral 51 denotes an insulating ring provided between the outer frame member 10 and the base portion 12.

  As shown in the figure, the above-described light emitting diode module, that is, the aluminum substrate 100 is fixed on the surface of the heat radiating member 13 in a state of being pressurized using a so-called frame-shaped mounting member 40. ing. In the figure, reference numeral 14 denotes a screw hole formed in advance on the board mounting disk surface of the heat radiating member 13, and reference numeral 15 denotes a fixing screw. The frame-shaped mounting member 40 includes at least an opening sufficient to expose the surface of the light emitting portion (phosphor layer 300) of the light emitting diode module for illumination upward. More specifically, the attachment member 40 has a shape that covers the outer periphery of the dam (dam member) 120 formed above.

  FIG. 9 shows the position (part) where the mounting member 40 comes into contact with the aluminum substrate 100 when the aluminum substrate 100 which is the above-described light emitting diode module is fixed by the mounting member 40. That is, as is clear from this figure, on the surface of the aluminum substrate 100 formed with a rectangular outer shape, two opposing sides (the left and right sides in the figure) are secured in order to ensure freedom of wiring and design. ) And an adjacent side (upper side in the figure). Therefore, in this embodiment, by using the remaining side (that is, the lower side in the figure) mainly and the side opposite to the side (that is, the upper side), the aluminum substrate 100 that is a light emitting diode module is obtained. An attachment structure that uses the attachment member 40 and fixes it in a pressurized state is employed. In addition, the state after fixing is shown in FIG. 10 which is the partially expanded sectional view.

  As described above, a pair of positive electrodes and negative electrodes (positive electrodes 131-1 and 131-2 and negative electrodes 132-1 and 132-2) are provided in order to ensure flexibility in wiring and design, respectively. However, these electrodes are preferably provided so as to be unevenly distributed in the vicinity of one side of the rectangular aluminum substrate 100 (that is, the upper side in the example of FIG. 9). That is, according to such a configuration, when the aluminum substrate is fixed to the surface of the aluminum substrate 100, by using a side opposite to the one side (hereinafter referred to as "other side"), for example, the above-described mounting member By 40, it becomes possible to fix in a pressurized state more reliably. That is, the heat generated from the aluminum substrate can be efficiently diffused to the outside, which contributes to extending the life of the light emitting diode module.

  DESCRIPTION OF SYMBOLS 100 ... Aluminum substrate, 110 ... Element mounting surface, 120 ... Dam (dam member), 130 ... Insulating film, 200 ... LED chip, 300 ... Fluorescent layer, 131-1, 131-2 ... Positive electrode, 132-1, 132-2 ... Negative electrode, 10 ... Outer frame member, 12 ... Base part, 13 ... Radiator (member), 20 ... Globe (light diffusion part), 40 ... Frame-shaped attachment member.

Claims (6)

A light emitting diode module having a plurality of light emitting diode chips mounted on a mounting surface of a rectangular plate-shaped substrate having excellent thermal conductivity,
Equipped with a substantially rectangular substrate made of a member with excellent heat conductivity,
On one surface of the substrate, an element mounting surface of a predetermined shape and an insulating layer around it are formed,
On the element mounting surface of the substrate, the plurality of light emitting diode chips are regularly arranged along a direction perpendicular to each other,
Positive and negative electrodes for supplying power to the plurality of light emitting diode chips are formed on the insulating layer of the substrate,
A plurality of the positive and negative electrodes are formed on the insulating layer, respectively.   In the light-emitting diode module according to claim 1, a frame-shaped dam member is formed around the plurality of light-emitting diode chips, and a fluorescent layer is formed inside the dam member. A plurality of positive and negative electrodes formed are formed outside the dam member.   3. The light emitting diode module according to claim 2, wherein each of the plurality of positive and negative electrodes formed is symmetric with respect to a center line of the module and is adjacent to one side of a substrate having a substantially rectangular shape and adjacent thereto. A light-emitting diode module, characterized in that the light-emitting diode module is unevenly distributed in the vicinity of the one side along two sides. The base part,
An outer frame member in which the base part is screwed and attached to a part thereof, and a radiator is attached to the inside;
In a lighting fixture provided with a light diffusion portion provided so as to cover the outer frame member,
A lighting fixture, wherein the light emitting diode module according to any one of claims 1 to 3 is pressure-mounted on an upper surface of the radiator.   5. The lighting fixture according to claim 4, wherein the light emitting diode module is fixed using a frame-shaped mounting member.   5. The luminaire according to claim 4, wherein the heat radiating body on which the light emitting diode module is pressure-mounted is thermally connected to a base on the negative electrode side of the base portion.

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