JP2016152104A - Semiconductor light emitting bulb and luminaire using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light emitting bulb having high heat radiation efficiency, and a luminaire.SOLUTION: An LED module 1 is mounted on a heat die 2 having heat insulation properties. A metal pin 4 has a continuous tip part 41, a flange part 42 and a rear end part 43. The tip part 41 has substantially the same length as the thickness of a printed wiring board 3, and it is for being fitted into a through-hole 3a of the printed wiring board 3. The flange part 42 is for holding the printed wiring board 3 together with the heat die 2. The rear end part 43 is for performing a heat radiation action. The tip part 41 of the metal pin 4 is directly connected to a metal die 21 of the heat die 2 via the through-hole 3a of the printed wiring board 3. A reflector 5 is provided in front of the LED module 1. The reflector 5 is supported by a housing 6 by a support member 7.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a semiconductor light-emitting bulb composed of a semiconductor light-emitting element such as a light-emitting diode (LED) element or a laser diode (LD) element, and an illumination device using the same, and more particularly to an improvement in the heat dissipation structure.

  Conventionally, halogen bulbs and HID (High Intensity Discharge) bulbs are often used in automobiles, motorcycle headlamps, fog lamps, etc., but in recent years, LEDs using light-emitting diode (LED) elements with energy saving and long life are used. Valves are attracting attention.

  In the LED element, the electric power not used as the light output among the electric power input to achieve the desired brightness becomes heat and heats itself. Therefore, the LED element has a negative characteristic that its life and performance are reduced by heat generated by itself. Moreover, the phosphor layer used for the purpose of changing the emission color by the combination with the LED element also has a negative characteristic due to heat. For this reason, in the LED bulb, the heat of the LED element and the phosphor layer is dissipated into the air using a heat dissipation structure such as a heat sink as a heat design for keeping the temperature of the LED element and the phosphor layer below an appropriate temperature. In particular, since a high-power LED element is used in order to realize a luminous flux such as a headlamp and a fog lamp, the heat dissipation structure is increased in size.

  FIG. 5 is a cross-sectional view showing a first conventional LED device.

  In FIG. 5, a heat-dissipating and insulating heat die 102 is mounted on an LED module 101 made of LED elements covered with a phosphor layer. The heat die 102 is provided on a printed wiring board 103 that also functions as a heat dissipation board. The printed wiring board 103 is bonded to the heat sink 105 via a thermal interface material (TIM) layer 104 to reduce the thermal resistance between the printed wiring board 103 and the heat sink 105.

  The printed wiring board 103 includes an insulating layer 1031 and a copper foil wiring layer 1032. A part of the copper foil wiring layer 1032 is formed in a through hole of the printed wiring board 103 to form a thermal via 1033. The LED elements of the LED module 101 are electrically connected to the copper foil wiring layer 1032 of the printed wiring board 103 through electrode terminals in the heat die 102 or bonding wires (not shown).

  In this way, in FIG. 5, the heat generated in the LED module 101 is radiated from the heat die 102 to the heat sink 105 mainly through the thermal via 1033 of the printed wiring board 103.

  FIG. 6 is a sectional view showing a second conventional LED device.

  In FIG. 6, a printed wiring board 203 is provided instead of the printed wiring board 103 of FIG. The printed wiring board 203 includes a metal core layer 2031 made of copper, aluminum, or the like, an insulating layer 2032 provided on the metal core layer 2031, and a copper foil wiring layer 2033 provided on the insulating layer 2032.

  In this way, in FIG. 6, heat generated in the LED module 101 is radiated from the heat die 102 to the heat sink 105 mainly through the metal core layer 2031 of the printed wiring board 203.

  However, in the first conventional LED device shown in FIG. 5, since the thermal via 1033 is formed by plating the through hole of the printed wiring board 103, the thickness of the thermal via 1033 is limited. The resistance cannot be reduced, and as a result, there are problems that the heat transfer coefficient is low and the heat dissipation efficiency is low.

  Further, in the second conventional LED device shown in FIG. 6, the thermal resistance is large due to the presence of the insulating layer 2032. As a result, there is still a problem that the heat transfer coefficient is small and the heat radiation efficiency is low.

  On the other hand, ensuring compatibility with halogen bulbs and HID bulbs by making the shape, dimensions and luminous flux distribution of LED devices the same as those of halogen bulbs and HID bulbs reduces versatility and manufacturing costs. Although necessary from the viewpoint, the first and second conventional LED devices shown in FIGS. 5 and 6 require a large printed wiring board 103 and 203 to be placed close to the light emitting region, and include a halogen bulb, an HID bulb, and the like. It is difficult to configure as an LED bulb that is compatible with each other.

  In order to solve the above-described problems, a semiconductor light emitting bulb according to the present invention includes a semiconductor light emitting element module, an insulating heat die on which the semiconductor light emitting element module is mounted, a printed wiring board in which a through hole is formed and performs only an energizing action. And a metal pin directly coupled to the heat die through the through hole of the printed wiring board.

  An illumination device according to the present invention includes the above-described semiconductor light-emitting bulb and a projection optical unit that is equipped with the semiconductor light-emitting bulb and projects light emitted from the semiconductor light-emitting bulb in a predetermined direction.

  According to the present invention, since the thermal resistance is reduced by the direct coupling between the semiconductor light emitting module and the metal pin, the thermal conductivity can be increased, and thus the heat dissipation efficiency can be increased.

It is sectional drawing which shows embodiment of the LED bulb which concerns on this invention. It is a whole perspective view of the LED bulb of FIG. It is a figure for demonstrating the assembly of the LED bulb of FIG. 1, Comprising: (A) is a disassembled perspective view, (B) is an assembly perspective view. The reflector type illuminating device which mounted | wore with the LED bulb of FIG. 1 is shown, (A) is a perspective view, (B) is sectional drawing. It is sectional drawing which shows a 1st conventional LED device. It is sectional drawing which shows the 2nd conventional LED device.

  FIG. 1 is a cross-sectional view showing an embodiment of an LED bulb according to the present invention.

  In FIG. 1, an LED module 1 is composed of an LED element 11 such as a blue LED element and a phosphor layer 12 covering the LED element 11 such as a YAG layer that converts blue light into yellow light, and is mounted on an insulating heat die 2. Yes. The heat die 2 includes a heat-dissipating metal die 21, an electrode terminal 22 connected to the LED element 11, and a metal die 21 and an insulating layer 23 surrounding the electrode terminal 22. However, the heat die 2 is not limited to the configuration of FIG.

  The printed wiring board 3 has wiring (not shown) for energization, but no drive circuit is provided. A through hole 3 a is provided in the center of the printed wiring board 3.

  The metal pin 4 has a continuous front end portion 41, a flange portion 42, and a rear end portion 43. The tip portion 41 has a length substantially the same as the thickness of the printed wiring board 3 and is for fitting into the through hole 3 a of the printed wiring board 3, and the collar portion 42 is for pressing against the heat sink 8. The rear end portion 43 mechanically couples with the heat sink 8 and performs a heat radiation function. The tip 41 of the metal pin 4 is directly soldered to the metal die 21 of the heat die 2 through the through hole 3a of the printed wiring board 3.

  In addition, a reflector 5 is provided in front of the LED module 1. The reflector 5 is formed by forming a reflective layer 52 such as aluminum on a resin layer 51, and is supported on a housing 6 by a support member 7. The support member 7 is a cylindrical member that is transparent on the entire periphery, but may be three or more thin rod members that are opaque.

  Further, as shown in FIG. 2 which is an overall perspective view of FIG. 1, a heat sink 8 is coupled to the rear end portion 43 of the metal pin 4.

  Next, the assembly of the LED bulb of FIG. 1 will be described with reference to FIGS. 1 and 2 and FIG. 3A is an exploded perspective view, and FIG. 3B is an assembled perspective view.

  First, referring to FIG. 3A, the electrode terminals of the heat die 2 on which the LED module 1 is mounted are soldered (reflowed or the like) to the printed wiring board 3.

  Next, solder 4a is attached to the tip 41 of the metal pin 4 and heated by a high-frequency heating method or the like, and is positioned by being inserted into the through hole 3a of the printed wiring board 3, and the tip 41 of the metal pin 4 is placed in the heat die 2. Solder to and bond directly. Thereby, the printed wiring board 3 is held by the heat die 2 and the metal pins 4. Therefore, mechanical coupling such as screws of the printed wiring board 3 is not required, and an area for that is not required. As a result, the printed wiring board 3 can be made very small.

  Next, referring to FIG. 3B, the rear end portion 43 of the metal pin 4 is inserted into the housing 6. Next, the support member 7 coupled to the reflector 5 shown in FIG. 1 is coupled to the housing 6 or coupled by a coupling means (not shown).

  Finally, the heat sink 8 shown in FIG. 2 is coupled to the rear end portion 43 of the metal pin 4 through silicon grease, a TIM layer or the like, thereby completing the LED bulb.

  As described above, the heat die 2 attached to the LED module 1 is directly coupled to the tip portion 41 of the metal pin 4 to reduce the thermal resistance. As a result, the thermal conductivity can be increased, and thus the heat dissipation efficiency can be increased. Furthermore, the heat dissipation efficiency can be further increased by directly coupling the heat sink 8 to the rear end portion 43 of the metal pin 4.

  A drive circuit for driving the LED element 11 is provided in the housing 6 and is connected to the wiring layer of the printed wiring board 3 by a wire (not shown) so that a DC drive current can be supplied to the LED element 11.

  4A and 4B show a reflector type illumination device equipped with the LED bulb of FIG. 1, wherein FIG. 4A is a perspective view and FIG. 4B is a cross-sectional view.

  In FIG. 4, the reflector 9 is provided so that the LED bulb of FIG. 1 may be covered. The reflector 9 constitutes a projection optical unit that projects the light emitted from the LED bulb in a predetermined direction, and forms a paraboloid in which a reflective layer such as Al is formed on a resin material.

  In FIG. 4B, as indicated by the arrow, the light L from the LED module 1 of the LED bulb is reflected by the reflector 5 and further reflected by the reflector 9 and emitted. Thereby, for example, a light emitter such as a filament of an incandescent lamp is reproduced. In this case, as shown in FIG. 4B, if the printed wiring board 3 is large, the optical path of the main light distribution from the reflector 5 to the reflector 9 is obstructed. However, in the present invention, the printed wiring board 3 is It is very small and there is no such obstruction of the main light distribution path.

  In the above-described embodiment, the LED element is used as the light emitting element, but the present invention can also be applied to other light emitting elements such as a laser diode (LD) element.

  Further, the present invention can be applied to any change within the obvious range of the above-described embodiment.

  The lighting device according to the present invention can be used for a lighting device using a vehicle lamp, for example, a headlamp, a fog lamp, a daytime running lamp (DRL), and a reflector such as a liquid projector.

1: LED module 11: LED element 12: phosphor layer 2: heat die 21: metal die 22: electrode 23: insulating layer 3: printed wiring board 3a: through hole 4: metal pin
41: tip portion 42: flange portion 43: rear end portion 4a: solder 5: reflector 6: housing 7: support member 8: heat sink
9: Reflector 101: LED module 102: Insulating heat die 103: Printed wiring board 1031: Insulating layer 1032: Copper foil wiring layer 1033: Thermal via 104: Thermal interface material (TIM) layer 105: Heat sink
203: Printed wiring board 2031: Metal core layer 2032: Insulating layer 2033: Copper foil wiring layer

Claims (5)

A semiconductor light emitting device module;
An insulating heat die on which the semiconductor light emitting element module is mounted;
A printed wiring board with through-holes that only conducts electricity;
A semiconductor light emitting bulb comprising: a metal pin directly coupled to the heat die through a through hole of the printed wiring board. The metal pin is
A front end having a length substantially the same as the thickness of the printed wiring board, and fitted into a through hole of the printed wiring board;
A flange that is continuous with the tip and grips the printed wiring board together with the heat die,
The semiconductor light-emitting bulb according to claim 1, further comprising: a rear end portion that is continuous with the flange portion and performs a heat dissipation action.   The semiconductor light-emitting bulb according to claim 1, further comprising a reflector positioned in front of the semiconductor light-emitting element module.   The semiconductor light-emitting bulb according to claim 1, further comprising a heat sink coupled to the metal pin. The semiconductor light-emitting bulb according to any one of claims 1 to 4,
An illumination apparatus comprising: a projection optical unit that is mounted with the semiconductor light-emitting bulb and projects light emitted from the semiconductor light-emitting bulb in a predetermined direction.