JP2017135257A - LED module and lighting fixture using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability for the temperature cycle, without impeding compaction of an LED package.SOLUTION: A terminal 179 connected electrically with a first land 121 via a solder 18 has a first overhang portion 171b hanging over the first land 121. The first overhang portion 171b is formed so that the length in a direction parallel with the mounting surface 11a is larger than the distance D1 between the terminal 179 and the mounting surface 11a in the thickness direction of an insulation board 11. When the terminal 179 is soldered, a portion of molten solder wraps around the lateral face of the first land 121. The area joined to the solder 18 can thereby be increased in the first land 121. Consequently, even if heat stress is applied to the solder 18, occurrence of crack for the solder 18 can be reduced, and reliability for the temperature cycle can be improved.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an LED module and a lighting fixture using the LED module.

  In general, an LED module is configured by a printed circuit in which a plurality of LED packages are mounted on a printed wiring board. The LED package has an anode terminal, a cathode terminal, and a heat dissipation pad. The anode terminal, the cathode terminal, and the heat dissipation pad are joined to the land of the printed wiring board via solder. In the printed circuit, in order to reduce the size of the LED module, the mounting density has been increased. As packaging density increases, LED packages are arranged at high density. Therefore, the temperature of the printed circuit easily rises due to the heat released from the LED package. Here, when the temperature of the printed circuit rises and falls, a thermal stress is generated due to a difference in thermal expansion coefficient between the anode terminal, the cathode terminal, the heat radiation pad, and the land. Therefore, thermal stress is applied to the solder that joins the LED package and the land. And there was a possibility that a crack may be generated in the solder due to repeated heat generation and cooling of the LED package, so-called temperature cycle.

  Conventionally, in order to prevent the occurrence of cracks in the solder, a configuration for dissipating heat released from the LED package to the outside of the LED package has been proposed. For example, in Patent Document 1, in a ceramic substrate body on which a semiconductor chip is mounted, a stress relaxation slit is formed between a portion where an external connection electrode is provided and a portion where a heat dissipation portion is provided. The configuration is described.

JP 2008-288536 A

  The stress relaxation slit described in Patent Document 1 is formed in the ceramic substrate body. Therefore, a space for forming a stress relaxation slit must be provided in the ceramic substrate body. Therefore, there is a restriction on the miniaturization of the ceramic substrate body in order to secure the space. Therefore, there has been a problem that downsizing of the LED package is hindered.

  The present invention has been made in view of the above problems, and an object of the present invention is to improve the reliability with respect to the temperature cycle without inhibiting the downsizing of the LED package.

  The LED module of the present invention includes a printed wiring board and an LED package mounted on the printed wiring board. The printed wiring board includes an insulating substrate, a conductor formed on the insulating substrate, and a first land. The LED package has a terminal electrically connected to the first land via solder, and the terminal is located outside the first land when viewed from the thickness direction of the insulating substrate. A first protruding portion that protrudes, and the first protruding portion has a length in a direction parallel to a mounting surface of the insulating substrate on which the conductor and the first land are formed; It is formed so as to be larger than the distance between the terminal and the mounting surface.

  The lighting fixture of the present invention includes the above-described LED module and a lighting fixture body having one or a plurality of the LED modules.

  According to the present invention, it is possible to improve the reliability with respect to the temperature cycle without inhibiting the downsizing of the LED package.

FIG. 1 is a cross-sectional view of a main part including an LED package of an LED module according to an embodiment of the present invention. 2A is a cross-sectional view of a main part including an anode terminal of the LED module same as above, and FIG. 2B is a cross-sectional view of a main part including a heat dissipation part of the LED module same as above. FIG. 3 is a plan view of a part of the printed wiring board of the LED module as seen from above. FIG. 4 shows a first modification of the LED module, FIG. 4A is a cross-sectional view of the main part including the anode terminal of the LED module, and FIG. 4B is a cross-sectional view of the main part including the heat dissipation part of the LED module. FIG. 5 is a plan view of a part of the printed wiring board as seen from above, showing a second modification of the LED module. FIG. 6 is an exploded perspective view in which a part of the lighting fixture according to the embodiment of the present invention is omitted. FIG. 7A is a perspective view seen from the front of the same lighting fixture, and FIG. 7B is a perspective view seen from the rear of the lighting fixture same as above.

  Hereinafter, an LED module according to an embodiment of the present invention will be described in detail with reference to the drawings.

  Note that the configurations described in the following embodiments are merely examples of the present invention. The present invention is not limited to the following embodiments, and various modifications can be made according to the design and the like as long as they do not depart from the technical idea of the present invention. Further, in the following description, unless otherwise specified, the vertical and horizontal directions are defined in the direction shown in FIG.

  The LED module 1 according to the embodiment includes a printed wiring board 10 and an LED package 17 mounted on the printed wiring board 10 as shown in FIG. The printed wiring board 10 includes an insulating substrate 11. The insulating substrate 11 is formed in a flat plate shape. The insulating substrate 11 is made of an insulating base material made of, for example, glass epoxy resin.

  An LED package 17 is disposed on the mounting surface 11 a (the upper surface in FIG. 1) of the insulating substrate 11. The LED package 17 includes a package body 170 and an LED chip 176 (see FIG. 1). The package body 170 is formed in a short shape extending in the left-right direction. The package body 170 is made of resin.

  The LED package 17 includes a heat dissipation part 173, an anode electrode 171, and a cathode electrode 172. The heat dissipating part 173 is provided in the center part in the left-right direction in the LED package 17. The heat dissipating part 173 is formed in a quadrangular prism shape extending in the vertical direction with a conductive material such as copper. The heat dissipating part 173 is disposed so as to penetrate from the upper surface to the lower surface of the package body 170. The upper end of the heat radiating part 173 is exposed from the upper surface of the package body 170. Further, the heat radiating part 173 is exposed from the lower surface of the package body 170.

  Further, the anode electrode 171 is provided on the left side with respect to the heat radiating portion 173. The anode electrode 171 is formed by bending a conductive material such as copper into a crank shape. The anode electrode 171 is disposed so as to penetrate from the upper surface to the lower left surface of the package body 170. The upper end of the anode electrode 171 is exposed from the upper surface of the package body 170. The lower end of the anode electrode 171 is exposed from the lower left surface of the package body 170. Further, the LED package 17 has a terminal 179. The terminal 179 has an anode terminal 171a and a cathode terminal 172a. An anode terminal 171 a is provided at the lower end of the anode electrode 171. The anode terminal 171a is formed in a short shape extending in the left-right direction.

  Further, the cathode electrode 172 is provided on the right side with respect to the heat radiating portion 173. The cathode electrode 172 is formed by bending a conductive material such as copper into a crank shape. The cathode electrode 172 is disposed so as to penetrate from the upper surface to the lower right surface of the package body 170. The upper end of the cathode electrode 172 is exposed from the upper surface of the package body 170. The lower end of the cathode electrode 172 is exposed from the lower right surface of the package body 170. A cathode terminal 172a is provided at the lower end of the cathode electrode 172. The cathode terminal 172a is formed in a short shape extending in the left-right direction. The cathode terminal 172a is formed so that the length in the left-right direction is the same as that of the anode terminal 171a. Further, the anode terminal 171a and the cathode terminal 172a are formed so that the length dimension is smaller than the length dimension width of the heat dissipating part 173 in the left-right direction. Since the cathode terminal 172a is configured in the same manner as the anode terminal 171a, a detailed description of the cathode terminal 172a is omitted.

  Further, the LED chip 176 is disposed on the upper surface of the heat radiating part 173. Therefore, the LED chip 176 and the heat dissipation part 173 are configured to be thermally contactable. A first electrode 176 a is provided on the upper surface of the LED chip 176. A second electrode 176b is provided on the upper surface of the LED chip 176 on the right side of the first electrode 176a. The first electrode 176a is electrically connected to the upper surface of the anode electrode 171 through the bonding wire 177a. The second electrode 176b is electrically connected to the upper surface of the cathode electrode 172 via the bonding wire 177b. The LED chip 176 is composed of a blue light emitting element. Further, a sealing portion 178 is disposed on the upper surface of the package body 170. The sealing part 178 is formed in a dome shape. Further, the sealing portion 178 seals the LED chip 176, the bonding wires 177a, 177b, and the like. The sealing portion 178 is formed of a mixture of a transparent silicone resin and phosphor particles 178a that emit light of different wavelengths by converting part of the light emitted from the LED chip 176. The sealing portion 178 contains, as phosphor particles 178a, for example, a yellow phosphor that emits broad yellow light when excited by blue light emitted from the LED chip 176 (for example, a YAG phosphor). To do. In the LED package 17, the blue light emitted from the LED chip 176 and the yellow light emitted from the yellow phosphor are emitted from the light emission surface of the sealing portion 178, and white light can be obtained.

  Further, the conductor 12 is formed on the mounting surface 11a of the insulating substrate 11 in a region E1 at the center in the front-rear direction and the center in the left-right direction (see FIG. 3). The conductor 12 is preferably formed of, for example, copper foil. The conductor 12 is preferably formed so that the thickness in the vertical direction (the thickness direction of the insulating substrate 11) is 50 [μm] or more. The conductor 12 is electrically connected to the terminal 179 of the LED package 17.

  Further, as shown in FIG. 1, a first land 121 and a first land 122 are formed on the mounting surface 11 a of the insulating substrate 11. The first land 121 and the first land 122 are formed by arranging the first land 121 and the first land 122 in this order from left to right. The first land 121 is disposed at a position where it can be electrically connected to the anode terminal 171 a via the solder 18. The first land 122 is disposed at a position where it can be electrically connected to the cathode terminal 172 a via the solder 18. Moreover, the 1st land 121 and the 1st land 122 are formed in the short shape extended in the front-back direction (refer FIG. 3). The first land 121 and the first land 122 are formed so that the length dimension is the same in the front-rear direction and the left-right direction. Moreover, as shown to FIG. 2A, the edge of the left-right direction of the boundary with the mounting surface 11a among the lower surfaces of the 1st land 121 is called the 2nd end P2. As shown in FIG. 3, the first connection conductor A1 is electrically connected to the first land 121 (see FIG. 3). The first connection conductor A <b> 1 is formed to extend leftward from the left end of the first land 121. Further, the first connection conductor A2 is electrically connected to the first land 122 (see FIG. 3). The first connection conductor A <b> 2 is formed on the mounting surface 11 a of the insulating substrate 11 so as to extend rightward from the right end of the first land 122. Then, the terminal 179 of the LED package 17 is electrically connected to a power supply device (not shown) via the first connection conductors A1 and A2.

  A second land 123 is formed on the mounting surface 11 a of the insulating substrate 11. As shown in FIG. 1, the second land 123 is formed between the first land 121 and the first land 122 in the left-right direction. The second land 123 is disposed so as to be in thermal contact with the lower surface of the heat radiating portion 173 via the solder 18. Therefore, the second land 123 radiates heat generated in the LED package 17 via the solder 18. The second land 123 is formed in a short shape extending in the front-rear direction (see FIG. 3). As shown in FIG. 3, the second land 123 is formed such that the length dimension is the same as the length dimension of the first lands 121 and 122 in the front-rear direction. Further, as shown in FIG. 1, the second land 123 is formed so that the length dimension is larger than the length dimension of the first lands 121 and 122 in the left-right direction.

  Moreover, as shown to FIG. 2B, the edge of the left-right direction of the boundary with the mounting surface 11a among the lower surfaces of the 2nd land 123 is called the 4th end P4. A second connection conductor B is connected to the second land 123 (see FIG. 3). As shown in FIG. 3, the second connection conductor B is formed so as to extend outward from both front and rear direction ends of the second land 123. The heat generated in the LED package 17 is transmitted to the second connection conductor B and radiated to the outside.

  A number of lands are formed on the mounting surface 11 a of the insulating substrate 11. However, in FIGS. 1-3, only the 1st land 121,122 and the 2nd land 123 are shown in figure.

  When the anode terminal 171a is projected onto the mounting surface 11a from above, the portion outside the projection range of the anode terminal 171a with respect to the first land 121 as shown in FIG. 2A is referred to as a first protruding portion 171b. Further, the length dimension in the direction parallel to the mounting surface 11a of the first protruding portion 171b (the left-right direction in FIG. 2A) is D1. The distance between the terminal 179 (the anode terminal 171a in FIG. 2A) and the mounting surface 11a is D2. The anode terminal 171a is formed such that the length dimension D1 in the left-right direction of the first protruding portion 171b is larger than the distance D2 between the mounting surface 11a and the anode terminal 171a in the vertical direction. Further, as shown in FIG. 2A, the left-right end of the boundary with the solder 18 in the lower surface of the first protruding portion 171b is referred to as a first end P1. The anode terminal 171a and the first land 121 are formed such that an angle θ1 formed by the straight line L1 connecting the first end P1 and the second end P2 and the normal line L2 of the mounting surface 11a is 45 ° or more. It is preferred that When the solder 18 is projected onto the mounting surface 11a from above, the portion outside the projection range of the solder 18 on the first land 121 as shown in FIG. 2A is referred to as a first fillet 18a. In the state shown in FIG. 2A, the surface of the first fillet 18a coincides with the straight line L1 connecting the first end P1 and the second end P2. Therefore, when the length dimension D1 is larger than the distance D2, the solder 18 is formed such that an angle θ1 formed by the surface of the first fillet 18a and the normal line L2 of the mounting surface 11a is 45 ° or more.

  Further, when the heat radiating portion 173 is projected onto the mounting surface 11a from above, the portion outside the projection range of the heat radiating portion 173 with respect to the second land 123 as shown in FIG. 2B is referred to as a second protruding portion 173b. The length dimension of the second protruding portion 173b in the direction parallel to the mounting surface 11a (the left-right direction in FIG. 2B) is D3. Further, the distance between the heat radiation part 173 and the mounting surface 11a is D4. The heat dissipating part 173 is formed such that the length dimension D3 in the left-right direction of the second protruding part 173b is larger than the distance D4 between the mounting surface 11a and the heat dissipating part 173 in the vertical direction. Further, as shown in FIG. 2B, the left-right end of the boundary with the solder 18 in the lower surface of the heat radiating portion 173 is referred to as a third end P3. The heat radiation part 173 and the second land 123 are formed so that the angle θ2 formed by the straight line L3 connecting the third end P3 and the fourth end P4 and the normal line L2 of the mounting surface 11a is 45 ° or more. It is preferred that When the solder 18 is projected onto the mounting surface 11a from above, a portion outside the projection range of the solder 18 with respect to the first land 121 as shown in FIG. 2B is referred to as a second fillet 18b. In the state shown in FIG. 2B, the surface of the second fillet 18b coincides with the straight line L1 connecting the first end P1 and the second end P2. Therefore, when the length dimension D3 is larger than the distance D4, the solder 18 is formed such that an angle θ1 formed by the surface of the second fillet 18b and the normal line L2 of the mounting surface 11a is 45 ° or more.

  Here, in the LED module, when the temperature of the printed circuit rises and falls, thermal stress is generated due to the difference in thermal expansion coefficient between the anode terminal, the cathode terminal, the heat dissipation pad, and the land. Therefore, thermal stress is applied to the solder between the anode terminal, the cathode terminal, the heat dissipation pad, and the land. The LED module has a temperature cycle. Therefore, there is a risk that the solder may crack.

  On the other hand, in the LED module 1, the anode terminal 171a has a length dimension D1 in the left-right direction of the first protruding portion 171b larger than the distance D2 between the mounting surface 11a and the anode terminal 171a in the vertical direction. Is formed. Therefore, when the anode terminal 171a is soldered, the melted solder spreads outward in the left-right direction along the lower surface of the anode terminal 171a. A part of the molten solder wraps around both side surfaces of the first land 121 in the left-right direction. Then, a part of the molten solder is cooled in a state where it adheres to the left and right side surfaces of the first land 121. Therefore, the solder 18 is bonded to the left and right side surfaces of the first land 121 with respect to the anode terminal 171a. Therefore, compared with the case where the anode terminal does not have the first protruding portion 171b, the area of the first land 121 bonded to the solder 18 can be increased. Accordingly, the bonding strength can be increased between the anode terminal 171a and the first land 121. Therefore, even if thermal stress occurs, the generation of cracks in the solder 18 between the anode terminal 171a and the first land 121 can be reduced, and the reliability with respect to the temperature cycle can be improved.

  When the length dimension D1 is greater than or equal to the distance D2, as shown in FIG. 2A, the solder 18 has an angle θ1 between the surface of the first fillet 18a and the normal L2 of the mounting surface 11a of 45 ° or more. Formed as follows. Accordingly, the bonding strength can be further enhanced between the anode terminal 171a and the first land 121. Therefore, the reliability with respect to the temperature cycle can be further improved.

  In the LED module 1, the cathode terminal 172a is formed in the same shape as the anode terminal 171a. Therefore, compared with the case where the cathode terminal does not have the first protruding portion 172b, the area of the first land 122 bonded to the solder 18 can be increased. Therefore, the bonding strength can be increased between the cathode terminal 172a and the first land 122. Therefore, even if thermal stress occurs, the generation of cracks in the solder 18 between the cathode terminal 172a and the first land 122 can be reduced, and the reliability with respect to the temperature cycle can be improved.

  When the length dimension D1 is equal to or greater than the distance D2, the solder 18 is formed such that an angle θ1 formed by the surface of the first fillet 18a and the normal line L2 of the mounting surface 11a is 45 ° or greater. Accordingly, the bonding strength can be further enhanced between the cathode terminal 172a and the first land 122. Therefore, the reliability with respect to the temperature cycle can be further improved.

  Further, in the LED module 1, the heat radiating portion 173 is formed such that the length dimension D3 in the left-right direction of the second protruding portion 173b is larger than the distance D4 between the mounting surface 11a and the heat radiating portion 173 in the vertical direction. Yes.

  Therefore, when the heat radiation part 173 is soldered, the melted solder spreads outward in the left-right direction along the lower surface of the heat radiation part 173. A part of the molten solder wraps around both side surfaces of the second land 123 in the left-right direction. Then, a part of the molten solder is cooled in a state of being attached to the left and right side surfaces of the second land 123. Therefore, the solder 18 is bonded to the left and right side surfaces of the second land 123 with respect to the heat radiating portion 173. Therefore, the area of the second land 123 joined to the solder 18 can be increased as compared with the case where the heat radiating portion does not have the second protruding portion 173b. Therefore, the bonding strength can be increased between the heat radiation part 173 and the second land 123. Therefore, even if thermal stress occurs, it is possible to reduce the occurrence of cracks in the solder 18 between the heat radiation part 173 and the second land 123, and to improve the reliability with respect to the temperature cycle.

  When the length dimension D3 is greater than or equal to the distance D4, as shown in FIG. 2B, the solder 18 has an angle θ1 between the surface of the second fillet 18b and the normal L2 of the mounting surface 11a of 45 ° or more. Formed as follows. Accordingly, the bonding strength between the heat radiation part 173 and the second land 123 can be further increased. Therefore, the reliability with respect to the temperature cycle can be further improved.

  By the way, in the ceramic substrate body of the LED package described in Patent Document 1, a slit for stress relaxation is formed between a portion where the external connection electrode is provided and a portion where the heat radiating portion is provided. And even if it uses the ceramic substrate main body of patent document 1, the reliability with respect to a temperature cycle can be improved. However, in the LED package described in Patent Document 1, a space for forming a stress relaxation slit must be provided in the ceramic substrate body. Therefore, downsizing of the ceramic substrate body is suppressed in order to ensure space. Therefore, there has been a problem that downsizing of the LED package is hindered. On the other hand, in the LED module 1, a stress relaxation slit is not formed in the package body 170. However, as described above, the LED package 17 can improve the reliability with respect to the temperature cycle even when the slit is not formed in the ceramic substrate body. Therefore, it can suppress that size reduction of the LED package 17 is inhibited.

  Further, in the LED module 1, a protective layer 13a is provided between the first land 121 and the second land 123 as shown in FIG. A protective layer 13b is provided between the first land 122 and the second land 123 as shown in FIG. The protective layers 13a and 13b are formed so as to extend along the front-rear direction (see FIG. 3). The protective layers 13a and 13b have solder resist formed on the mounting surface 11a. As shown in FIG. 1, two first gases are provided on the mounting surface 11 a by a space sandwiched between the first land 121 and the protective layer 13 a and a space sandwiched between the protective layer 13 a and the second land 123. It is preferable that a cut groove 14a is formed (see FIG. 1). In addition, two first gas vent grooves 14b are formed on the mounting surface 11a by a space sandwiched between the second land 123 and the protective layer 13b and a space sandwiched between the protective layer 13b and the first land 122. It is preferable that it is (refer FIG. 1). Further, as shown in FIG. 3, the first gas vent groove 14a and the first gas vent groove 14b are formed so as to extend to reach an area E2 as an area outside the area E1.

  In the mounting surface 11a, a protective layer 13c is provided in a region E3 as a region outside E2. The protective layer 13c is formed by applying a solder resist to the mounting surface 11a. In the protective layer 13c, two second gas vent grooves 16 are formed in the front end portion and the rear end portion, respectively. Each of the second gas vent grooves 16 is formed so as to incline outward in the left-right direction as the region E3 goes outward in the front-rear direction (see FIG. 3). Each of the second gas vent grooves 16 is formed such that the protective layer 13c is cut into a groove shape and penetrates the region E3. That is, the second gas vent groove 16 connects the region E3 where the protective layer is not provided and the outside of the printed wiring board 10. Accordingly, the first gas vent grooves 14a and 14b are configured to be able to vent from the outside of the printed wiring board 10 through the region E2 where the protective layer is not provided and the second gas vent groove 16.

  By the way, in the process of melting the solder, gas as a flux decomposition component is generated. The gas becomes voids and tends to remain inside the hardened solder 18. If there is a void inside the solder 18, the thermal conductivity is reduced by the void. Therefore, there is a possibility that cracks are likely to occur due to the void in the solder 18 as a base point.

  On the other hand, in the LED module 1, two first gas vent grooves 14 a are formed by a space sandwiched between the first land 121 and the protective layer 13 a and a space sandwiched between the protective layer 13 a and the second land 123. Is formed. In addition, two first gas vent grooves 14b are formed on the mounting surface 11a by a space sandwiched between the second land 123 and the protective layer 13b and a space sandwiched between the protective layer 13b and the first land 122. Has been. The first gas vent grooves 14 a and 14 b are configured to be able to vent from the printed wiring board 10 through the region E 2 where the protective layer is not provided and the second gas vent groove 16. Therefore, even when a void is generated inside the molten solder during soldering, the void is outside the printed wiring board 10 via the gas vent grooves 14a and 14b, the region E2, and the second gas vent groove 16. To be released. Therefore, voids inside the solder 18 can be reduced as compared with the case where the first gas vent grooves 14a and 14b and the second gas vent groove 16 are not provided. Therefore, cracks generated in the solder 18 can be reduced.

  Although the short-shaped 1st land 121 extended in the front-back direction was shown as a land of the LED module 1, it is not limited to this. For example, as in Modification 1 of the embodiment shown in FIG. 4A, the first land 1210 may be formed in a trapezoidal shape whose width in the left-right direction becomes narrower from the bottom to the top. Thereby, compared with the 1st land 121, the area of the side surface of the left-right direction can be increased. Therefore, in the first land 1210, the area bonded to the solder 18 can be increased. Therefore, the bonding strength can be enhanced between the anode terminal 171a and the first land 1210. Further, as in Modification 1 of the embodiment shown in FIG. 4B, the second land 1230 may be formed in a trapezoidal shape whose width in the left-right direction becomes narrower from the bottom to the top. Thereby, compared with the 2nd land 123, the area of the side surface of the left-right direction can be increased. Therefore, in the second land 1230, the area bonded to the solder 18 can be increased. Accordingly, the bonding strength can be increased between the heat radiation part 173 and the second land 1230. In addition to the first land 121 and the second land 1230, the first land 122 may be formed in a trapezoidal shape whose width in the left-right direction becomes narrower from the bottom to the top. Moreover, the shape of the 1st land 121,122 and the 2nd land 123 is not limited to a short shape or a trapezoid shape, You may change into arbitrary shapes.

  Moreover, it is preferable not to provide a protective layer in the region E2 of the mounting surface 11a. However, for example, as in Modification 2 of the embodiment shown in FIG. 5, a protective layer 13d may be provided in the region E2 of the mounting surface 11a. When the protective layer 13d is provided, it is preferable to extend the first gas vent grooves 14a and 14b in the front-rear direction. Then, the first gas vent grooves 14a and 14b and the second gas vent groove 16 are directly communicated with each other. Accordingly, the first gas vent grooves 14 a and 14 b are configured to be able to vent from the printed wiring board 10 through the second gas vent grooves 16.

  As described above, the LED module 1 according to the embodiment includes the printed wiring board 10 and the LED package 17 mounted on the printed wiring board 10. The printed wiring board 10 includes an insulating substrate 11, a conductor 12 and a first land 121 formed on the insulating substrate 11. The LED package 17 has a terminal 179 that is electrically connected to the first land 121 via the solder 18. The terminal 179 has a first protruding portion 171 b that protrudes outside the first land 121 when viewed from the thickness direction of the insulating substrate 11. The first protruding portion 171b has a length D1 in a direction parallel to the mounting surface 11a of the insulating substrate 11 on which the conductor 12 and the first land 121 are formed, and the terminal 179 in the thickness direction of the insulating substrate 11 and the mounting surface. It is formed to be larger than the distance D2 with 11a.

  If the LED module 1 according to the embodiment is configured as described above, when the terminal 179 is soldered, the molten solder spreads outward along the terminal 179. A part of the molten solder goes around the side surface of the first land 121 in the direction parallel to the mounting surface 11a. Then, a part of the molten solder is cooled in a state of being attached to the side surface in the direction parallel to the mounting surface 11 a of the first land 121. Therefore, the solder 18 is also bonded to the side surface of the terminal 179 in the direction parallel to the mounting surface 11 a of the first land 121. Therefore, compared with the case where the terminal does not have the first protruding portion 171b, the area of the first land 121 bonded to the solder 18 can be increased. Accordingly, the bonding strength can be increased between the terminal 179 and the first land 121. Therefore, even if thermal stress is applied to the solder 18 between the terminal 179 and the first land 121, the occurrence of cracks in the solder 18 can be reduced, and the reliability with respect to the temperature cycle can be improved.

  Further, in the LED module 1 according to the embodiment, when the terminal 179 and the first land 121 are solder-bonded, when viewed from at least one of the directions orthogonal to the thickness direction of the insulating substrate 11, the following Such a condition holds. The end of the surface of the first protruding portion 171b to be soldered is called a first end P1. Further, the end closest to the first protruding portion 171b among the ends of the contact surface between the mounting surface 11a of the first land 121 and the first land 121 is referred to as a second end P2. The terminal 179 and the first land 121 have an angle θ1 formed by a straight line L1 connecting the first end P1 and the second end P2 and the normal line L2 of the mounting surface 11a to be 45 ° or more. Preferably it is formed.

  If the LED module 1 according to the embodiment is configured as described above, the bonding strength between the terminal 179 and the first land 121 can be further increased. Therefore, the reliability with respect to the temperature cycle can be further improved.

  As described above, the LED module 1 according to the embodiment includes the printed wiring board 10 and the LED package 17 mounted on the printed wiring board 10. The printed wiring board 10 includes an insulating substrate 11, a conductor 12 and a first land 122 formed on the insulating substrate 11. The LED package 17 has a terminal 179 that is electrically connected to the first land 122 via the solder 18. The terminal 179 has a first protruding portion 172 b that protrudes outside the first land 122 when viewed from the thickness direction of the insulating substrate 11. The first protruding portion 172b has a length D1 in a direction parallel to the mounting surface 11a of the insulating substrate 11 on which the conductor 12 and the first land 122 are formed, and the terminal 179 in the thickness direction of the insulating substrate 11 and the mounting surface. It is formed to be larger than the distance D2 with 11a.

  If the LED module 1 according to the embodiment is configured as described above, when the terminal 179 is soldered, the molten solder spreads outward along the terminal 179. A part of the molten solder wraps around the side surface of the first land 122 in the direction parallel to the mounting surface 11a. Then, a part of the molten solder is cooled in a state of being attached to the side surface in the direction parallel to the mounting surface 11 a of the first land 122. Accordingly, the solder 18 is also bonded to the side surface of the terminal 179 in the direction parallel to the mounting surface 11 a of the first land 122. Therefore, compared to the case where the terminal does not have the first protruding portion 172b, the area of the first land 122 bonded to the solder 18 can be increased. Therefore, the bonding strength can be increased between the terminal 179 and the first land 122. Therefore, even if thermal stress is applied to the solder 18 between the terminal 179 and the first land 122, the occurrence of cracks in the solder 18 can be reduced, and the reliability with respect to the temperature cycle can be improved.

  Further, in the LED module 1 according to the embodiment, when viewed from at least one of the directions orthogonal to the thickness direction of the insulating substrate 11 with the terminals 179 and the first lands 122 being solder-bonded, the following Such a condition holds. An end of the surface of the first protruding portion 172b to be soldered is referred to as a first end P1. The end closest to the first protruding portion 172b among the ends of the contact surface between the mounting surface 11a of the first land 122 and the first land 122 is referred to as a second end P2. The terminal 179 and the first land 122 have an angle θ1 formed by a straight line L1 connecting the first end P1 and the second end P2 and the normal line L2 of the mounting surface 11a to be 45 ° or more. Preferably it is formed.

  If the LED module 1 according to the embodiment is configured as described above, the bonding strength between the terminal 179 and the first land 122 can be further increased. Therefore, the reliability with respect to the temperature cycle can be further improved.

  In the LED module 1 according to the embodiment, the printed wiring board 10 includes the second land 123, and the LED package 17 is connected to the second land 123 via the solder 18, and generates the second heat generated. The land 123 has a heat dissipating portion 173 that dissipates heat. The heat dissipating part 173 has a second protruding part 173 b that protrudes outside the second land 123 when viewed from the thickness direction of the insulating substrate 11. The second protruding portion 173b is formed so that the length D3 in the direction parallel to the mounting surface 11a is larger than the distance D4 between the heat radiation portion 173 and the mounting surface 11a in the thickness direction of the insulating substrate 11. preferable.

  If the LED module 1 which concerns on embodiment is comprised as mentioned above, when the thermal radiation part 173 is soldered, melt | dissolution solder will spread outside along the thermal radiation part 173. FIG. A part of the molten solder goes around the side surface of the second land 123 in the direction parallel to the mounting surface 11a. Then, a part of the molten solder is cooled in a state of being attached to the side surface in the direction parallel to the mounting surface 11 a of the second land 123. Therefore, the solder 18 is also bonded to the side surface in the direction parallel to the mounting surface 11 a of the second land 123 with respect to the heat radiating portion 173. Therefore, the area of the second land 123 joined to the solder 18 can be increased as compared with the case where the heat radiating portion does not have the second protruding portion 173b. Therefore, the bonding strength can be increased between the heat radiation part 173 and the second land 123. Therefore, even if thermal stress occurs, the occurrence of cracks in the solder 18 can be reduced, and the reliability with respect to the temperature cycle can be improved.

  In the LED module 1 according to the embodiment, when viewed from at least one of the directions orthogonal to the thickness direction of the insulating substrate 11 with the heat dissipation portion 173 and the second land 123 soldered together, The condition is met. The end of the surface of the second protruding portion 173b to be soldered is referred to as a third end P3. Of the ends of the contact surface between the mounting surface 11a and the second land 123, the end closest to the second protruding portion 173b is referred to as a fourth end P4. The heat radiation part 173 and the second land 123 are formed so that the angle θ2 formed by the straight line L3 connecting the third end P3 and the fourth end P4 and the normal line L2 of the mounting surface 11a is 45 ° or more. It is preferable that

  If the LED module 1 according to the embodiment is configured as described above, the bonding strength can be further increased between the heat dissipation portion 173 and the second land 123. Therefore, the reliability with respect to the temperature cycle can be further improved.

  The first land 1210 is preferably formed in a substantially trapezoidal shape when viewed from at least one of the directions orthogonal to the thickness direction of the insulating substrate 11.

  If the LED module 1 according to the embodiment is configured as described above, the area of the surface facing the terminal 179 can be increased compared to the first land 121. Therefore, the area bonded to the solder 18 can be increased. Accordingly, the bonding strength can be increased between the terminal 179 and the first land 1210.

  The second land 1230 is preferably formed in a substantially trapezoidal shape when viewed from at least one of the directions orthogonal to the thickness direction of the insulating substrate 11.

  If the LED module 1 according to the embodiment is configured as described above, the area of the surface facing the heat dissipation part 173 can be increased as compared with the second land 123. Therefore, the area bonded to the solder 18 can be increased. Accordingly, the bonding strength can be increased between the heat radiation part 173 and the second land 1230.

  Next, the lighting fixture 200 using the LED module 1 will be described with reference to FIGS. 6 and 7.

  As illustrated in FIG. 6, the lighting fixture 200 includes a plurality (four in the illustrated example) of light source units 210 and a lighting fixture main body 220. Moreover, it is preferable that the lighting fixture 200 has the panel unit 230, the fixing member 240, the protective cover 250, the connection box 260, etc.

  As shown in FIG. 6, the light source unit 210 includes two LED modules 1 that are light source units, a heat dissipation block 211 that is a heat dissipation unit, a lens block (not shown), a waterproof member 217, and the like. The LED module 1 includes a plurality (11 in the illustrated example) of LED packages 17 (light emitting diodes), a printed wiring board 10, and a plurality (two in the illustrated example) of connecting terminal blocks 215. The connection terminal block 215 is mounted on the mounting surface 11 a of the insulating substrate 11. The connection terminal block 215 is electrically connected to both ends of the DC circuit of the plurality of LED packages 17 individually. The LED packages 17 are preferably electrically connected in series via the first connection conductors A1 and A2.

  As shown in FIG. 6, the heat dissipation block 211 includes a base portion 212 and a plurality of heat dissipation portions 213. The base part 212 is formed in a short flat plate shape. Moreover, it is preferable that the base part 212 is formed of aluminum or an aluminum alloy. In the heat dissipation block 211, two LED modules 1 are attached to the front surface of the base portion 212 by screws. The heat radiation part 213 is formed in a short thin plate shape. Moreover, it is preferable that the thermal radiation part 213 is formed with aluminum or aluminum alloy. The plurality of heat radiating portions 213 are arranged side by side with the thickness direction aligned in the left-right direction with a space therebetween. Further, the plurality of heat radiating portions 213 are formed so as to protrude rearward from the rear surface of the base portion 212.

  The waterproof member 217 is formed in a short frame shape. The waterproof member 217 is preferably formed of an elastic member having electrical insulation properties such as silicone rubber. Further, the waterproof member 217 is configured to be interposed between the base portion 212 of the heat dissipation block 211 and the lighting fixture main body 220.

  The luminaire main body 220 has a frame portion 221 as shown in FIG. The frame portion 221 is formed in a flat rectangular tube shape. In addition, it is preferable that the frame part 221 is formed in the shape of a flat square tube with aluminum or an aluminum alloy. And the base part 212 of the thermal radiation block 211 is fixed to the lighting fixture main body 220 in the state pinched | interposed into the frame part 221 via the waterproof member 217. FIG.

  As shown in FIG. 7, the fixing member 240 is integrally formed with a fixing plate 241 and a pair of arm pieces 242 that rise upward from the left and right ends of the fixing plate 241. Note that the fixing member 240 is preferably formed of a metal plate such as a stainless steel plate. Each of the pair of arm pieces 242 has a circular insertion hole 245 passing through the tip. Then, the bolt 246 inserted through the insertion hole 245 is screwed into a bearing portion (not shown) of the lighting fixture main body 220. That is, the fixing member 240 is coupled to the luminaire main body 220 via a pair of bearings (not shown), and can rotatably support the luminaire main body 220 about the bolt 246 as a rotation axis. A disc-shaped scale plate 247 is attached to the left bearing portion. The scale plate 247 is engraved with a scale having an angle centered on the bolt 246. Thus, the angle of the luminaire main body 220 with respect to the arm piece 242 can be read.

  As shown in FIG. 7, the panel unit 230 includes two panels 231, two panel pressers 232, and two panel packings 233. Each panel 231 is formed in a short flat plate shape. The panel 231 is preferably formed of a transparent synthetic resin material such as an acrylic resin or a polycarbonate resin, or a transparent material such as glass. Each panel packing 233 is formed in a short frame shape. Each panel packing 233 is preferably formed of an elastic material such as silicone rubber. A groove (not shown) in which the peripheral portion of the panel 231 can be fitted is formed on the inner peripheral surface of each panel packing 233. The panel 231 is inserted from the front into the frame portion 221 of the luminaire main body 220 with the peripheral portion fitted in the groove on the inner peripheral surface of the panel packing 233. Each panel presser 232 is formed in a short frame shape. Each panel presser 232 is formed so as to cover the front surface of the panel packing 233. Each panel pressing member 232 is preferably formed of a metal such as a stainless steel plate. The panel 231 and the panel packing 233 are sandwiched between the lighting fixture body 220 and the panel presser 232 and are fixed to the lighting fixture body 220.

  As shown in FIG. 7, the protective cover 250 includes a pair of first cover bodies 251 and a pair of second cover bodies 252. The protective cover 250 is formed in a box shape by the cover bodies 251 and 252. The pair of first cover bodies 251 constitutes the left and right walls of the protective cover 250. The pair of second cover bodies 252 constitute upper and lower walls and a rear wall (bottom wall) of the protective cover 250. The first cover body 251 is formed in a short flat plate shape using a metal plate such as a stainless steel plate. In the first cover body 251, narrow fixing pieces protrude from the three sides excluding the front side. Each of these three fixing pieces is provided with a plurality (two or four) of screw insertion holes arranged in the longitudinal direction. Further, the first cover body 251 is provided with a trapezoidal notch in the vicinity of the center in the vertical direction on the front end side. The protective cover 250 is attached to the luminaire main body 220 so as to cover the heat dissipation blocks 211 of the four light source units 210.

  As described above, the lighting fixture 200 according to the embodiment includes the LED module 1 and the lighting fixture main body 220 including one or a plurality of LED modules 1.

  Since the lighting fixture 200 according to the embodiment is configured as described above, the LED module 1 can be provided with improved reliability with respect to the temperature cycle without hindering downsizing.

DESCRIPTION OF SYMBOLS 1 LED module 10 Printed wiring board 11 Insulating board 11a Mounting surface 12 Conductor 17 LED package 200 Lighting fixture 220 Lighting fixture main body 121,122 1st land 123 2nd land 171b, 172b 1st protrusion part 173 Heat radiation part 173b 2nd protrusion part 179 Terminal 200 Lighting fixture 220 Lighting fixture main body 1210 First land 1230 Second land D1 Length in a direction parallel to the mounting surface of the first protrusion D2 Distance between the terminal and the mounting surface D3 Parallel to the mounting surface of the second protrusion D4 Distance between heat sink and mounting surface L1 Straight line connecting first end and second end L2 Normal line of mounting surface L3 Straight line connecting third end and fourth end P1 First end P2 First 2nd end P3 3rd end P4 4th end θ1 angle θ2 angle

Claims (6)

A printed wiring board, and an LED package mounted on the printed wiring board,
The printed wiring board has an insulating substrate, and a conductor and a first land formed on the insulating substrate,
The LED package has a terminal electrically connected to the first land via solder,
The terminal has a first protruding portion that protrudes outside the first land when viewed from the thickness direction of the insulating substrate,
The first protruding portion has a length in a direction parallel to the mounting surface of the insulating substrate on which the conductor and the first land are formed, and a distance between the terminal and the mounting surface in the thickness direction of the insulating substrate. An LED module that is formed to be larger than the LED module.   When the terminal and the first land are solder-bonded, the terminal and the first land are the first protrusion when viewed from at least one of the directions orthogonal to the thickness direction of the insulating substrate. A first end as an end of a surface to be soldered, and a second end as an end closest to the first protruding portion among ends of a contact surface between the mounting surface of the first land and the first land. 2. The LED module according to claim 1, wherein an angle formed by a straight line connecting the ends and a normal line of the mounting surface is 45 ° or more. The printed wiring board has a second land,
The LED package has a heat radiating part connected to the second land via the solder and radiating generated heat to the second land,
The heat radiating portion has a second protruding portion that protrudes outside the second land as viewed from the thickness direction of the insulating substrate,
The second protruding portion is formed so that a length in a direction parallel to the mounting surface is larger than a distance between the heat radiating portion and the mounting surface in a thickness direction of the insulating substrate. The LED module according to claim 1 or 2.   When the heat dissipation portion and the second land are solder-bonded, the heat dissipation portion and the second land are the second land when viewed from at least one of the directions orthogonal to the thickness direction of the insulating substrate. A third end as an end of a surface to be soldered of the protruding portion and a second end as the end closest to the second protruding portion among the ends of the contact surface between the mounting surface of the second land and the second land. The LED module according to claim 3, wherein an angle formed by a straight line connecting the four ends and a normal line of the mounting surface is 45 ° or more.   The said 1st land and the said 2nd land are formed in the substantially trapezoid shape seeing from at least one direction among the directions orthogonal to the thickness direction of the said insulated substrate. The LED module according to claim 1.   A lighting fixture comprising: the LED module according to any one of claims 1 to 5; and a lighting fixture body having one or a plurality of the LED modules.

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