JP5582633B2 - LED lighting device - Google Patents

Description

The present invention relates to an LED lighting device using an LED package mounting structure for mounting an LED package to a housing.

Conventionally, an LED lighting device using a light emitting diode (hereinafter referred to as “LED”) is known (see, for example, Patent Document 1).
As shown in FIG. 8, the LED lighting device 100 described in Patent Document 1 includes a substrate 101 that is a printed wiring board, a metal attachment member 102, a light control body 103, and a cover body 104. A plurality of LEDs 105 are mounted on the front side of the substrate 101, and an LED drive circuit 106 is disposed on the back side to constitute an LED package 107.

The metal attachment member 102 is a member for attaching the LED package 107, and is formed of a thermally conductive metal plate. The metal mounting member 102 has a ring plate-shaped mounting surface 108 for mounting to a mounting portion such as a ceiling surface with screws or the like, and a rising piece 109 that rises from the inner periphery of the mounting surface 108. A plurality of convex portions 110 are provided on the outer peripheral surface of the rising piece 109.
The cover body 104 is formed in a ring shape with resin, has an engaging portion 111 that is engaged with the convex portion 110 of the metal mounting member 102 at the upper portion of the inner peripheral surface, and the light control body 103 at the lower portion of the inner peripheral surface. It has the holding part 112 holding the outer peripheral surface.

  Accordingly, the substrate 101 is sandwiched between the metal mounting member 102 and the light control body 103 by the cover body 104 held by the convex portions 110 of the metal mounting member 102 holding the light control body 103. Thus, the heat generated by the LED 105 is conducted through the mounted substrate 101 and is radiated to the mounting surface through the metal mounting member 102 that is in contact with the substrate 101.

Japanese Patent Laying-Open No. 2005-71711 (Page 4, FIG. 3)

By the way, when attaching an LED package to a housing | casing, mounting an LED package to a base material by soldering and attaching this base material to a housing | casing may be performed.
That is, as shown in FIG. 9, in the LED lighting device 120, the LED package 123 mounted with the LED chip 121 and sealed with the sealing material 122 is mounted on the mounting substrate 124 with the solder 125 to form the LED module 126. The LED module 126 is attached to a metal heat dissipating casing 127 which is a casing of a lighting device or the like.

  Further, as shown in FIG. 10, in the LED lighting device 130, the LED package 133 mounted with the LED chip 131 and sealed with the sealing material 132 and attached to the metal heat radiating plate 138 is attached to the mounting substrate 134 with the solder 135. The LED module 136 is formed by mounting, and the LED module 136 is attached to the heat dissipation housing 137 with an adhesive 139.

However, in the LED lighting devices 120 and 130 shown in FIG. 9 and FIG. 10, a metal case such as aluminum is used as the housing in order to improve heat dissipation, but the base material is made of, for example, glass. In the case of a resin system such as epoxy, the thermal conductivity of the base material is poor, and the thermal resistance is large at the contact surface between the base material and the housing. For this reason, since heat is not efficiently transmitted to the housing, there is a problem that the temperature of the LED rises and the light emission efficiency of the LED decreases.

  Moreover, when using metal members, such as copper and aluminum, for a base material, although heat dissipation performance is improved, since the thickness of the insulating layer of a base material is thin, withstand voltage performance falls. For this reason, it is common to provide a heat conductive sheet with a high withstand voltage on the back of the base material, but since the sheet itself is soft, for example, distortion occurs between the screw fixing part and the part that is not, and as a result There is a problem that the base material is distorted to reduce long-term reliability. Furthermore, since the sheet having high voltage resistance has a low thermal conductivity, there is a problem that the heat conduction is hindered.

The present invention has been made in order to solve the conventional problems. By efficiently transferring the heat generated by the LED package to the heat generating housing, the temperature rise of the LED package can be avoided and the luminous efficiency of the LED package can be improved. It aims at providing the LED lighting apparatus which can prevent a fall.

LED lighting device of the present invention includes a metal substrate, said that on a metal substrate from Oite said metal substrate is provided without protruding to the outside, and a circuit board having a circuit pattern, wherein the An LED chip is mounted on a metal substrate without a mount member, the LED chip is connected to the circuit pattern of the circuit board, and the LED chip, a part of the circuit board, and a part of the circuit pattern are sealed. Sealed with a stopper, and the end of the circuit pattern is exposed on the circuit board provided on the metal base without being sealed with the sealing material, and the circuit and LED package at the end of the pattern being wire connected, and metals made of the heat radiating housing, with is provided on the metallic radiator housing, wherein the LED package is mounted, a thermally conductive Electric extinction Combines sex, and have a heat radiation property, a function of transferring heat from the LED package to the heat radiating housing, withstand voltage performance holds the insulating state between the heat radiating housing and the LED package A hard body member made of ceramics, which is a member having both a function to ensure heat resistance, a function to dissipate heat from the LED package into the air by radiation, and a function to suppress distortion of the LED package. The first distance which is a horizontal distance from the position of the side surface of the end portion of the circuit pattern to the position of the side surface of the end portion of the metal substrate, and the position of the side surface of the end portion of the metal substrate. A second distance which is a horizontal distance to the position of the side surface of the end of the hard member, a third distance corresponding to the thickness of the circuit board, and a fourth distance corresponding to the thickness of the metal substrate. The hard part made of ceramics The equivalent to the thickness, and said a fifth distance is a distance greater than each of the first distance to fourth distance, formed by summing, between the heat radiation housing and the circuit pattern, structure An LED package mounting structure in which a creepage distance, which is the shortest distance along the surface of the body, is set to 1.2 mm or more is provided.

  With this configuration, since the hard member having both thermal conductivity and electrical insulation is interposed between the LED package and the heat dissipation housing, the heat generated by the LED package is dissipated through the hard member. It can be transferred to the housing to dissipate heat. Further, since the hard member has electrical insulation, it is possible to maintain the insulation state between the LED package and the heat radiating housing and to ensure the withstand voltage performance. Further, since the hard member is hard and difficult to deform, the long-term reliability of the LED package can be maintained by suppressing the distortion of the LED package.

  With this configuration, since the hard member has heat radiation properties and high thermal emissivity, the heat generated by the LED package can be radiated into the air by radiation through the hard member, and the LED package Heat generation can be suppressed.

  With this configuration, since the hard member is made of ceramics, the withstand voltage breakdown performance is high, and since there is no secular change, there is no change in dimensions, and distortion can be suppressed to ensure long-term reliability of the LED package.

  With this configuration, the creepage distance between the electric charging part of the LED package and the heat radiating case is set to 1.2 mm or more, so that insulation between the electric charging part and the heat radiating case can be ensured.

  With this configuration, since the mounting structure of the LED package described above is used, a hard member having both thermal conductivity and electrical insulation is interposed between the LED package and the heat dissipation housing, and the LED package emits light. Heat can be transferred to the heat radiating housing via the hard member to radiate heat. Further, since the hard member has electrical insulation, it is possible to maintain the insulation state between the LED package and the heat radiating housing and to ensure the withstand voltage performance. Moreover, long-term reliability of the LED package can be maintained by suppressing the distortion of the LED package.

In the present invention, since the hard member having both thermal conductivity and electrical insulation is interposed between the LED package and the heat radiating housing, the heat generated by the LED package is radiated through the hard member. It can be transferred to the housing to dissipate heat. Further, since the hard member has electrical insulation, it is possible to maintain the insulation state between the LED package and the heat radiating housing and to ensure the withstand voltage performance. In addition, by suppressing the distortion of the LED package, it is possible to provide an LED lighting device having an effect that the long-term reliability of the LED package can be maintained.

Sectional drawing which shows the attachment structure of the LED package of 1st Embodiment which concerns on this invention It is sectional drawing which shows the attachment method of a LED module and a thermal radiation housing | casing, (A) is a figure at the time of attaching ceramics to a housing | casing with a screw, (B) is a figure at the time of attaching with an adhesive agent Explanatory drawing of creepage distance between electrical charging part and heat dissipation housing Sectional drawing which shows the attachment structure of the LED package of 2nd Embodiment which concerns on this invention It is sectional drawing which shows the attachment structure of the LED package of 3rd Embodiment which concerns on this invention, (A) is a figure at the time of arranging the head part of a screw in the ceramic recessed part, (B) is a nut in the ceramic recessed part. Figure when placed Sectional drawing which shows the attachment structure of the LED package of 4th Embodiment which concerns on this invention Sectional drawing which shows the LED lighting apparatus of 5th Embodiment which concerns on this invention. Sectional drawing of the LED lighting apparatus using the conventional LED package mounting structure Sectional drawing which shows the attachment structure of the conventional LED package Sectional drawing which shows another example of the attachment structure of the conventional LED package

(First embodiment)
Hereinafter, an LED package mounting structure according to a first embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, in the LED package mounting structure 20 according to the present invention, an LED chip 21 is mounted on a metal base 23 and connected to a circuit pattern 221 on a circuit board 22, and a sealing material 24 such as silicone resin is used. Then, the LED package 25 is formed. The circuit pattern 221 is connected to the electric wire 27 by a solder 26 at a predetermined position.

  A ceramic base 28 (for example, alumina ceramic) that is a hard member having both thermal conductivity and electrical insulation is attached to the metal base 23 in the LED package 25 with an adhesive 29 to form an LED module 31. ing. The LED module 31 is attached to, for example, a metal heat radiating housing 11 that is a housing of the LED lighting device. That is, the ceramics 28 are interposed between the LED package 25 and the heat radiating housing 11.

  Joining between the LED module 31 and the heat radiating housing 11 can be performed by screws 32 as shown in FIG. Alternatively, as shown in FIG. 2B, the LED module 31 can be attached to the heat dissipation housing 11 with an adhesive 33.

  At this time, the creeping distance L between the circuit pattern 221 that is an electric charging portion of the LED package 25 and the heat radiating housing 11 is set to 1.2 mm or more. Here, the creepage distance L is the shortest distance along the surface of the insulator between the two conductive portions (that is, between the circuit pattern 221 and the heat radiating housing 11). As shown in FIG. 3, the horizontal distance from the end 222 of the circuit pattern 221 to the end 231 of the metal base 23 is L1, the thickness of the circuit board L2, the thickness of the metal base 23 is L3, and the metal base When the horizontal distance from the end 231 of the material 23 to the end 281 of the ceramic 28 is L4 and the thickness of the ceramic 28 is L5, L = L1 + L2 + L3 + L4 + L5> 1.2 mm.

  As described above, according to the LED package mounting structure 20 of the first embodiment of the present invention described above, the LED package 25 is mounted on the ceramic 28 which is a hard member with the adhesive 29 without heating, and the LED module 31 is mounted. Since it is formed, it is not necessary to use solder when forming the LED module as in the prior art. For this reason, the LED package can be easily supported without a large facility such as a reflow apparatus. In addition, it is possible to avoid thermal degradation due to a thermal history of about 260 ° C. that occurs during reflow during mounting, and to prevent a decrease in initial luminous flux.

  In addition, since the ceramic 28 having thermal conductivity is interposed between the heat radiating casing 11 and the LED package 25, the heat generated by the LED package 25 is transmitted to the heat radiating casing 11 through the ceramic 28. Can dissipate heat. In addition, since the ceramic 28 has electrical insulation, it is possible to maintain the insulation state between the LED package 25 and the heat radiating housing 11 and ensure the withstand voltage performance. Further, since the ceramic 28 is a hard body, the long-term reliability of the LED module 31 can be maintained by suppressing the distortion of the LED package 25.

Further, since the ceramic 28 has heat radiation, the heat generated by the LED package 25 can be radiated to the air by radiation through the ceramic 28, and the heat generation of the LED package 25 can be suppressed.
Further, since the creepage distance between the circuit pattern 221 that is an electric charging portion of the LED package 25 and the heat dissipation casing 11 is set to 1.2 mm or more, the insulation between the circuit pattern 221 and the heat dissipation casing 11 is ensured. be able to.

(Second Embodiment)
Next, the mounting structure of the LED package of 2nd Embodiment which concerns on this invention is shown in FIG. In addition, the same code | symbol is attached | subjected to the site | part which is common in the attachment structure of the LED package which concerns on 1st Embodiment mentioned above, and the overlapping description is abbreviate | omitted.
As shown in FIG. 4, in the LED package mounting structure 20 </ b> B according to the second embodiment, the adhesive used when the LED package 25 is bonded to the ceramics 28 in the LED package mounting structure 20 according to the first embodiment. Instead of 29, the LED package 25 was joined to the ceramic 28 with screws 34 to form an LED module 31. The LED module 31 is joined to the heat radiating housing 11 in the same manner as in the first embodiment.

  As described above, according to the LED package mounting structure 20B of the second embodiment of the present invention described above, the same operations and effects as those of the LED package mounting structure 20 of the first embodiment described above can be obtained.

(Third embodiment)
Next, an LED package mounting structure according to a third embodiment of the present invention is shown in FIG. In addition, the same code | symbol is attached | subjected to the site | part which is common in the attachment structure of the LED package which concerns on 1st Embodiment and 2nd Embodiment mentioned above, and the overlapping description is abbreviate | omitted.

As shown in FIG. 5, in the LED package mounting structure 20 </ b> C according to the third embodiment, the screws 34 used when the LED package 25 is bonded to the ceramics 28 in the LED package mounting structure 20 </ b> B according to the second embodiment. Instead, the LED package 25 was joined to the ceramic 28 using the bolt 35 and the nut 36 to form the LED module 31.
FIG. 3A shows a case where the head of the bolt 35 is embedded in the recess 282 provided in the ceramic 28 and FIG. 3B shows a case where the nut 36 is embedded in the recess 282 of the ceramic 28. Show.

  As described above, according to the LED package mounting structure 20C of the third embodiment of the present invention described above, the same functions and effects as the LED package mounting structures 20A and 20B of the first and second embodiments described above are obtained. Can be obtained.

(Fourth embodiment)
Next, an LED package mounting structure according to a fourth embodiment of the present invention is shown in FIG. In addition, the same code | symbol is attached | subjected to the site | part which is common in the attachment structure of the LED package which concerns on 1st Embodiment thru | or 3rd Embodiment mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 6, in the LED package mounting structure 20 </ b> D according to the fourth embodiment, the LED package 25 is stacked on the ceramics 28 without bonding, and the metal substrate 23 of the LED package 25 is pressed by the cover 37. The cover 37 was fastened to the heat radiating housing 11 with screws 38. Specifically, the LED package 25 and the ceramics 28 were simultaneously attached to the heat radiating housing 11 by pressing and fixing the metal base 23 with the cover 37.

  As described above, according to the LED package mounting structure 20D of the fourth embodiment of the present invention described above, the same functions and effects as those of the LED package mounting structures 20A to 20C of the first to third embodiments described above are obtained. Can be obtained. Furthermore, since there is no step of joining the LED package 25 and the ceramic 28, work efficiency can be improved.

(Fifth embodiment)
Next, FIG. 7 shows an LED lighting device according to a fifth embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the site | part which is common in the mounting structure 20A-20D of LED package which concerns on 1st Embodiment thru | or 4th Embodiment mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 7, the LED lighting device 10 has a heat radiating casing 11 that is a fixture main body that is attached to, for example, a ceiling surface 12 that is a mounted portion, and the heat radiating casing 11 has, for example, a cylindrical frame 13. Installed. A reflection plate 14 having a conical shape is provided inside the frame 13, and a transparent panel 15 made of, for example, resin is provided in front of the reflection plate 14 in the irradiation direction. The LED package 25 on which the LED chip 21 is mounted is attached to the heat radiating housing 11 corresponding to the top of the reflector 14 by the LED package attachment structure 20 described above.

In FIG. 7, the LED package 25 is attached to the ceramics 28 with screws 34 to form a LELD module 31 (see FIG. 4), and this LED module 31 is attached to the heat dissipation housing 11 with screws 32 (see FIG. 2). However, the present invention is not limited to this.
In the LED lighting device 10 shown in FIG. 7, only one LED module 31 is provided, but a plurality of LED modules 31 are generally provided.

The LED package mounting structure 20 and the LED lighting device 10 using the same according to the present invention are not limited to the above-described embodiments, and appropriate modifications and improvements can be made.
For example, in each of the above-described embodiments, the case where the ceramic 28 is used as the hard member has been illustrated. However, as the hard member, a resin or a metal whose surface is subjected to an insulation treatment can be used.

DESCRIPTION OF SYMBOLS 10 LED illuminating device 11 Radiating case 20 LED package mounting structure 21 LED chip 221 Circuit pattern (electric charging part)
23 Metal substrate 25 LED package 28 Ceramics (hard member)

Claims (1)

Has a metal substrate, is provided without protruding from Oite the metal substrate outwardly on the metal substrate, and a circuit board having a circuit pattern, and via the mounting member to the metal substrate LED chip without being mounted, the LED chip is connected to the circuit pattern of the circuit board, the LED chip, a part of the circuit board and a part of the circuit pattern is sealed with a sealing material, An end portion of the circuit pattern is not sealed with the sealing material, but is exposed on the circuit board provided on the metal base material, and an electric wire is formed on the end portion of the circuit pattern. A connected LED package;
And metallic steel radiator housing,
Together provided on the metallic radiator housing, wherein the LED package is mounted, both thermal conductivity and electrical insulation properties, and have a heat radiation property, the heat from the LED package heat radiating housing A function of transmitting to the LED package, a function of maintaining an insulation state between the LED package and the heat radiating housing to ensure a withstand voltage performance, a function of radiating heat from the LED package into the air by radiation, A hard member made of ceramics, which is a member having the function of suppressing distortion of the LED package ;
Have
The first distance , which is the horizontal distance from the position of the side surface of the end portion of the circuit pattern to the position of the side surface of the end portion of the metal substrate, and the hard position made of the ceramic from the position of the side surface of the end portion of the metal substrate. A second distance which is a horizontal distance to the position of the side surface of the end of the body member, a third distance corresponding to the thickness of the circuit board, a fourth distance corresponding to the thickness of the metal base, The circuit pattern and the heat radiating casing , which are equivalent to the thickness of the hard member made of ceramics , and are totaled with a fifth distance that is larger than each of the first distance to the fourth distance. LED package mounting structure in which the creepage distance, which is the shortest distance along the surface of the structure, is set to 1.2 mm or more,
An LED lighting device comprising:

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