JP2015135744A - lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lamp capable of reducing the temperature of a lighting circuit.SOLUTION: A lamp according to an embodiment comprises: a radiator 1 serving as a hollow case opening on one end; a substrate 3 having a through-hole formed at the center and provided on one end of the radiator 1; a plurality of semiconductor light-emitting elements 4 provided circumferentially to be along one end of the substrate 3 and the through-hole; a lighting circuit 7 that includes a circuit board 71 and a circuit component 72 having a heating component 721 mounted on the circuit board 71, and that is provided within the radiator 1 so that the heating component 721 is located within a region of the through-hole when the radiator 1 is viewed from one end side; and a mouthpiece 81 provided on the other end of the radiator 1.

Description

  Embodiments described herein relate generally to a lamp.

  For example, a lamp using light emission of a semiconductor such as a light emitting diode is used for illumination or display. The lamp includes a semiconductor light emitting element, a lighting circuit that supplies power to the semiconductor light emitting element, and a member that houses the semiconductor light emitting element and the lighting circuit.

  Since a semiconductor light emitting device has a long life, it is known that this type of lamp has a long life compared to a lamp such as a conventional light bulb. However, the lamp may reach the end of its life because the lighting circuit has a longer life than the semiconductor light emitting element. Since the life of the lighting circuit depends on the temperature of the circuit member of the lighting circuit during lighting, it is desirable that the temperature of the lighting circuit during lighting is low.

Japanese Patent No. 5257627

  The problem to be solved by the present invention is to provide a lamp capable of reducing the temperature of the lighting circuit.

To achieve the above object, a lamp according to an embodiment includes a hollow case having one end opened; a substrate having a through hole in the center and provided at one end of the case; one end of the substrate; A plurality of semiconductor light emitting elements provided circumferentially along the through hole; and a circuit component including a circuit board and a heat generating component mounted on the circuit board, and the case is viewed from one end side. A heating circuit provided in the case so that the heat-generating component is located in the region of the through hole; and a power supply unit provided on the other end side of the case. .

  According to the present invention, the temperature of the lighting circuit can be reduced.

It is a figure for demonstrating the lamp | ramp of 1st Embodiment. It is a figure for demonstrating the external appearance of the lamp | ramp of 1st Embodiment. It is a figure for demonstrating the state which looked at the lamp | ramp of 1st Embodiment from the one end side of the case, (a) is the state which removed the globe, the board | substrate, and the heat sink, (b) is the state which removed the glove. is there. It is a figure for demonstrating the difference in the temperature of the lighting circuit of the lamp | ramp of 1st Embodiment, and the conventional lamp | ramp. It is a figure for demonstrating the cross section of the lamp | ramp of 1st Embodiment. It is a figure for demonstrating the lamp | ramp of 2nd Embodiment. It is a figure for demonstrating the temperature change of the lighting circuit when the shape of a cover member is changed in the lamp | ramp of 2nd Embodiment. It is a figure for demonstrating the other example of the lamp | ramp of this embodiment.

  (First embodiment)

  The first embodiment will be described with reference to FIGS. FIG. 1 is a diagram for explaining the lamp of the first embodiment, FIG. 2 is a diagram for explaining the appearance of the lamp of the first embodiment, and FIG. 3 is a case of the lamp of the first embodiment. It is a figure for demonstrating the state seen from the one end side.

  The lamp of the present embodiment is an LED lamp used for illumination and display applications. The radiator 1, the radiator 2, the substrate 3, the LED 4, the globe 5, the resin case 6, the lighting circuit 7, the base 81, and the insulating ring 82. It consists of In the present embodiment, in the central axis of the lamp, the direction in which the globe 5 is located when viewed from the base 81 is referred to as one end side, and the direction in which the base 81 is located as viewed from the globe 5 is referred to as the other end side. explain.

  The radiator 1 is a hollow case made of a material having excellent thermal conductivity, such as aluminum, ceramic, or resin, and having an opening on one end side. A flat substrate mounting portion 11 is formed around the opening on one end side of the radiator 1, and a peripheral wall 12 protruding in one end direction is formed around the flat substrate mounting portion 11. The peripheral wall 12 is formed with a ring-shaped projecting wall 13 projecting in the direction of the internal space, and a ring-shaped groove 14 is formed between the projecting wall 13 and the substrate mounting portion 11. Further, four cutouts 15 are formed in the protruding wall 13 at intervals of 90 degrees, and the cutouts 15 are connected to the ring-shaped groove 14. On the inner space side of the radiator 1, three boss portions 16 projecting from the inner wall toward the center are formed at intervals of 120 degrees. The boss portion 16 and the surface on one end side of the substrate mounting portion 11 are formed flush with each other. A screw hole 17 is formed on one end side of the boss portion 11.

  The heat sink 2 is a thin plate made of a material having excellent thermal conductivity, for example, a metal such as aluminum. The heat radiating plate 2 has a through hole formed in the center, and four protrusions 21 protruding in the central direction are formed at intervals of 90 degrees on the inner wall portion of the through hole. The protrusion 21 is formed with a screw hole (not shown). The heat radiating plate 2 is formed with screw holes (not shown) at positions corresponding to the screw holes 17 of the heat radiating body 2, and the heat radiating plate 2 is screwed into these screw holes so that the heat radiating plate 2 is attached to the board mounting portion 11. Attached to the heat conductive.

  The substrate 3 is a thin plate made of a material having excellent thermal conductivity, for example, aluminum or ceramic. The heat sink 2 is formed with a through hole in the center, and four protrusions 31 protruding in the center direction are formed at intervals of 90 degrees on the inner wall portion of the through hole, like the protrusion 21 of the heat sink 2. Has been. The protrusion 31 is formed with a notch (not shown) for screw insertion corresponding to the screw hole of the protrusion 21 of the heat radiating plate 2, and the screw 32 is screwed into the notch and the screw hole. The substrate 3 is attached to the heat sink 2 in a heat conductive manner. A connector receiving portion 33 is provided on one end side of the substrate 3.

  The LED 4 is a semiconductor light emitting element called a so-called light emitting diode. Specifically, it is a light emitting diode in which a light emitting chip that emits blue light is mounted on a package of resin or the like, and a yellow phosphor layer is covered so as to cover the light emitting chip. In the present embodiment, 27 pieces are mounted on one end side of the substrate 21 in a circumferential shape so as to be along the through holes at substantially equal intervals.

  The globe 5 is a transparent or milky white translucent cover mainly composed of polycarbonate. The globe 5 has a spherical shape and is joined at its maximum diameter portion. Specifically, the hemispherical top portion 51 and the enlarged diameter base portion 52 are integrated by, for example, ultrasonic welding. On the inner side of the other end side of the base portion 52 of the globe 5, four protrusions 53 that are slightly smaller in width than the notches 15 of the radiator 1 are formed at intervals of 90 degrees, and the grooves 15 are formed via the notches 15. 14, the protrusion 53 is sandwiched between the substrate mounting portion 11 and the protruding wall 13, and the globe 5 is held by the radiator 1.

  The insulating case 6 is a case made of a material that is excellent in electrical insulation, such as polybutylene terephthalate, and has lower thermal conductivity than metal. The insulating case 6 has a main body portion 61 and a protruding portion 62. The main body 61 has three recesses 63 at intervals of 120 degrees on the inner space side. The concave portion 63 corresponds to the boss portion 16, that is, the main body portion 61 is disposed in the internal space of the radiator 1 by fitting the concave portion 63 to the boss portion 16. The main body 61 has an opposing wall 64 formed on the inner space side. A pair of opposing walls 64 is formed, and a line connecting the spaces between the opposing walls 64 is shifted with respect to the center of the main body 61. The protruding portion 62 is formed on the other end side of the main body portion 61 and is disposed so as to protrude to the outside from the opening on the other end side of the radiator 1. A screw-like protrusion 65 is formed on the outer surface portion protruding from the radiator 1.

  The lighting circuit 7 is a circuit for supplying desired power to the light emitting module 2 and is accommodated in the insulating case 6. The lighting circuit 6 includes a circuit board 71 provided with predetermined metal wiring on a board having electrical insulation such as epoxy, a circuit component 72 mounted on the circuit board 71, and a connector 73 connected to the connector receiving portion 33. have. The circuit component 72 includes a heat-generating component 721 such as a switching element such as a transformer or FET, and a non-heat-generating component 722 such as a capacitor that generates relatively less heat than the heat-generating component 721. The lighting circuit 7 is disposed inside the insulating case 6 such that the circuit board 71 is held by the pair of opposing walls 64 of the insulating case 6 so that the surface on which the circuit component 72 is mounted is along the lamp axis. At this time, at least the heat generating component 721 is located in the region of the through hole of the substrate 2 when the heat radiating body 1 is viewed from one end side.

  The base 81 is a power supply unit attached to the socket of the appliance, is provided at the other end of the lamp, and is electrically connected to the lighting circuit 7. The base 81 is provided between a spiral part that is a spiral metal part formed on the side surface of the base 81, an eyelet that is a metal part formed on the bottom surface of the base 81, and between the spiral part and the eyelet. It is comprised by the insulation part (not shown) which is a part electrically insulated from each other.

  The insulating ring 82 is a ring-shaped member made of an insulating member, and is provided on the outer peripheral portion of the protruding portion 62 of the insulating case 6 so as to be positioned between the radiator 1 and the base 81.

  In the lamp of this embodiment, when AC power is supplied to the base 81 from an external power source, the lighting circuit 7 performs rectification and DC-DC conversion, and DC power is supplied to the LED 4. As a result, the LED 4 is lit, but the LED 4 and the lighting circuit 7 generate heat. The heat generated in the LED 4 is transmitted to the heat radiating body 1 through the heat radiating plate 2 and the substrate 3 and radiated. However, since a through hole is provided in the center of the heat radiating plate 2 and the substrate 3, the heat is directed outward. It is transmitted only, not in the central direction. That is, the heat generating component 721 of the lighting circuit 7 is located in the region of the through hole of the substrate 2 when the radiator 1 is viewed from one end side, so that the heat of the LED 4 causes the heat dissipation plate 2 and the substrate 3 to move. Thus, the heat is not transmitted to the heat generating component 721, and the temperature rise of the heat generating component 721 can be suppressed. Moreover, since the temperature in the space in the globe 5 is relatively low even during lighting, the heat generating component 721 can be cooled through the through hole. Therefore, the temperature during lighting of the lighting circuit 7 becomes low, and the life of the lighting circuit 7 can be extended.

  FIG. 4 is a diagram for explaining the difference in temperature between the lighting circuit of the lamp of this embodiment and the conventional lamp. (A) is a conventional lamp (conventional example 1) in which a substrate 2 on which LEDs 4 are mounted is arranged at the center of a heat sink 2 without a through hole, and (b) is a circular arrangement of LEDs 4 on the heat sink 2 without a through hole. The conventional lamp (conventional example 2), in which the substrate 2 mounted in a shape is arranged, is a lamp (example) of this embodiment, and the temperature of the lighting circuit 7 during lighting is indicated by the density of dots. The higher the density, the higher the temperature. The number of LEDs mounted and the input power are the same. In both (a) to (c), the width W of the circuit board 71 is 45.6 mm, and the size L of the through hole of the board 3 in (c) is 43 mm.

  From the results, it can be seen that the temperature of the lighting circuit 7 during lighting of the lamp of the example is generally lower than that of the lamps of the conventional examples 1 and 2. Specifically, based on the lamp of Conventional Example 1, the temperature at the LED side point A on the lighting circuit 7 is −0.5 ° C. in Conventional Example 2, which is not much different from the lamp of Conventional Example 1. In the example lamp, the temperature was greatly reduced to -7.7 ° C. Further, the temperature at the base side point B on the lighting circuit 7 is −0.2 ° C. in the conventional example 2, which is not much different from the lamp of the conventional example 1, whereas the temperature of the lamp of the example is as large as −4.7 ° C. Decreased. As described above, most of the lighting circuit 7 is located in the region of the through holes of the heat sink 2 and the substrate 3, so that the heat of the LED 4 passes through the heat sink 2 and the substrate 3. That the lighting circuit 7 is cooled by being exposed to an atmosphere having a relatively low temperature in the globe 5. As described above, when the heat generating component 721 of the lighting circuit 7 is disposed in the through hole region of the substrate 2 when the heat radiator 1 is viewed from one end side, the temperature rise of the lighting circuit 7 is remarkably suppressed. be able to.

  Next, the temperature difference of the lighting circuit 7 when the size L of the through holes of the heat sink 2 and the substrate 3 and the width W of the circuit board 71 are changed will be described with reference to FIG. The temperature difference is based on the temperatures at points A and B in the lamp of FIG. 4B in which through holes are not formed in the heat sink 2 and the substrate 3.

  From the results, it can be seen that as L / W increases, the temperatures at points A and B decrease. This is because when L / W is small, heat is easily transferred to the circuit board 71 via the LED 4, the board 3, and the heat sink 2, and the cooling effect due to the relatively low temperature atmosphere in the globe 5 is reduced. Because. When L / W is 0.6 or more, the temperature difference tends to further increase. Therefore, it is desirable that L / W is 0.6 or more, and further 0.75 or more. The effect becomes higher as L / W becomes larger, but if L / W is made too large, the place where the LED 4 is placed cannot be secured, or the circuit board 71 becomes smaller and the placement of the circuit component 72 becomes difficult. L / W is desirably 1.4 or less.

In the first embodiment, a through hole is formed in the center of the substrate 3, a plurality of semiconductor light emitting elements are provided in a circumferential shape along one end side of the substrate 3 and along the through hole, and the circuit board 71 and the circuit board 71 are provided. When the lighting circuit 7 having the circuit component 72 including the heat generating component 721 mounted thereon is viewed from the one end side, the heat dissipating body 1 is positioned so that the heat generating component 721 is located in the region of the through hole. As a result, the temperature rise of the lighting circuit 7, particularly the heat generating component 721, can be suppressed. Further, when the size of the through hole is L (mm) and the width of the circuit board 71 is W (mm), the effect can be further enhanced by setting L / W to 0.6 or more. This effect can also be obtained by interposing a heat radiating plate 2 having a similar through hole between the heat radiating body 1 and the substrate 3.

(Second Embodiment)

  FIG. 6 is a diagram for explaining a lamp according to a second embodiment of the present invention. About each part of this 2nd Embodiment, the same part as each part of 1st Embodiment is shown with the same code | symbol, and the description is abbreviate | omitted.

  In the present embodiment, the cover member 9 is provided in the through hole of the substrate 3. The cover member 9 is a resinous member having lower thermal conductivity than the heat radiating plate 2 and the substrate 3, for example, having a thermal conductivity of 0.5 W / mK or less. It is also desirable to have high reflectivity. As a result, if the heat sink 2 and the substrate 3 are hollow, light loss can occur. The light can be reflected by the cover member 9 to increase the light utilization efficiency, and the base 81 is used in an upward state. Moreover, it can suppress that the foreign material falls into the globe 5 from the lighting circuit 7 part, and becomes obstructive of light emission.

  In the present embodiment, the cover member 9 has a mounting portion 91 and a convex portion 92. The attachment portion 91 has a screw hole, and is a portion that is screwed together with the screw 32 together with the screw hole of the protruding portion 21 of the heat sink 2 and the protruding portion 31 of the substrate 3. The convex portion 92 is a portion that protrudes from the mounting portion 91 in the direction of the base 81, passes through the through holes of the heat sink 2 and the substrate 3, and the flat plate portion that is the bottom portion is located in the vicinity of one end side of the lighting circuit 7. doing. In this shape, an atmosphere having a relatively low temperature in the globe 5 is easily transmitted to the lighting circuit 7, so that the temperature rise of the lighting circuit 7 can be suppressed as in the first embodiment.

  FIG. 7 is a diagram for explaining a temperature change of the lighting circuit when the shape of the cover member 9 is changed in the lamp of the second embodiment. (A) uses a cover member 9 on a flat plate, (b) uses a cover member 9 protruding in the direction of the glove 5, and (c) uses a cover member 9 protruding in the direction of the base 81. This is the case.

  As can be seen from the figure, in the lamp (c), the temperature of the lighting circuit is reduced as compared with (a) and (b). Compared with the lamp in FIG. 3 (c), the temperature at the LED side point A on the lighting circuit 7 is + 5 ° C. in (a), + 4.7 ° C. in (b), + 1.8 ° C. in (c), the base side The temperature at the point B was + 2.7 ° C. in (a), + 2.7 ° C. in (b), and + 1.7 ° C. in (c). That is, if it is a shape like FIG.7 (c), the temperature rise of the lighting circuit 7 can be suppressed to the same extent as 1st Embodiment. In particular, if the distance D between the convex portion 92 and the circuit board 71 is 3 mm or less, and optimally, the convex portion 92 and the circuit board 71 are in contact with each other, the temperature of the lighting circuit 7 can be lowered.

In the second embodiment, since the cover member 9 having a lower thermal conductivity than the substrate 2 is provided in the through hole of the substrate 2, the light utilization efficiency can be improved and the adhesion of foreign matter to the globe 5 is suppressed. can do.

In addition to the above effects, the cover member 9 is provided with a convex portion 92 and the convex portion 92 protrudes in the direction of the base 81 and is positioned in the vicinity of the lighting circuit 7. Moreover, the temperature rise of the lighting circuit 7 can be suppressed. Moreover, the temperature rise can be further suppressed by setting the distance D between the convex portion 92 and the circuit board 71 to 3 mm or less.

  The present invention is not limited to the above embodiments, and various modifications are possible.

  For example, the shape of the through holes of the substrate 2 and the heat sink 3 is not limited to a circular shape, and may be a polygonal shape.

  Silicone resin may be filled in the whole or a part of the insulating case 6 where the lighting circuit 7 is arranged. Thereby, the temperature rise of the lighting circuit 7 can be further suppressed. As shown in FIG. 8, by filling the inside of the protrusion 62 with a silicone resin, a temperature reduction effect of about 5 ° C. can be expected as compared with the case of not filling.

  Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

1 Heat Dissipator 2 Heat Dissipator 3 Substrate 4 LED
5 Globe 6 Insulating Case 7 Lighting Circuit 71 Circuit Board 72 Circuit Component 721 Heating Component 722 Non-heating Component 81 Base 82 Insulating Ring 9 Cover Member

Claims (5)

A hollow case opened at one end; a substrate having a through hole in the center and provided at one end of the case; provided circumferentially along one end of the substrate and along the through hole A plurality of semiconductor light emitting elements; and a circuit component including a circuit board and a heat generating component mounted on the circuit board, and when the case is viewed from one end side, the heat generating component is within the region of the through hole. A lamp comprising: a lighting circuit provided inside the case so as to be positioned; and a power feeding unit provided on the other end side of the case. The lamp according to claim 1, wherein L / W is 0.6 or more, where L (mm) is the size of the through hole and W (mm) is the width of the circuit board. The through hole is provided with a cover member having lower thermal conductivity than the substrate, the cover member has a convex portion, the convex portion projects in the direction of the power feeding portion, and is in the vicinity of the lighting circuit. The lamp according to claim 1 or 2, wherein the lamp is located in the position. The circuit board is disposed inside the case so that a surface on which the circuit component is mounted is along a lamp axis, and a distance D between the convex portion and the circuit board is 3 mm or less. The lamp according to claim 3. The substrate is provided on a heat radiating plate, the heat radiating plate has a through hole in the center, and one end of the case is connected so that the through hole of the heat radiating plate and the through hole of the substrate communicate with each other. The lamp according to any one of claims 1 to 4, wherein the lamp is provided on a side.

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