JP6392637B2 - LED module and LED lighting apparatus - Google Patents

Description

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

  In recent years, instead of conventional fluorescent lamps, LED lighting fixtures using light emitting diodes (LEDs) with low energy consumption and long life as a light source are becoming widespread.

  Since the light emitting diode has a small light emission amount per element, in the LED lighting apparatus, a plurality of light emitting diodes are mounted on a printed wiring board. The plurality of light emitting diodes are generally juxtaposed in a plane on a printed wiring board as disclosed in, for example, Japanese Patent Application Laid-Open No. 2009-170114.

  Such an LED lighting apparatus is used by being installed on a ceiling at a high position in a gymnasium or a factory, for example, with the light emitting diode mounting surface facing downward. When the installation density of this LED luminaire is low, the illumination having a light distribution characteristic having a light intensity in a shallow angle direction, for example, in a range from 0 ° to 45 ° downward from the horizontal direction is lower than the light intensity vertically downward. Required to keep the illuminance uniform.

JP 2009-170114 A

  However, in the above-described conventional LED lighting fixture, a plurality of light emitting diodes are arranged in a plane on a flat printed wiring board, and thus a light source formed by the plurality of light emitting diodes has directivity. In such an LED lighting apparatus, the light distribution angle (the angle formed by the direction in which the luminous intensity is halved with respect to the maximum luminous intensity) is about 120 degrees, and the luminous intensity is 50% in the direction of about 60 degrees from the normal direction. It becomes. That is, in the conventional LED lighting fixture, the luminous intensity of the front surface (normal direction) of the light emitting diode mounting surface is strong, but the light intensity is weaker as the angle becomes shallower with respect to the front surface of the light emitting diode mounting surface. When the installation density of LED lighting fixtures is high, a relatively uniform illuminance distribution can be obtained by using LED lighting fixtures having such light distribution characteristics. However, when the installation density of LED lighting fixtures is low, there is an inconvenience that a non-uniform illuminance distribution with locally bright portions exists.

  On the other hand, in order to improve this inconvenience, an LED lighting apparatus has been devised in which a lens, a prism, or the like is laminated on the light output side of the light emitting diode to refract the light from the light source in the lateral direction. However, such LED lighting fixtures inevitably have a complicated structure and an increased cost due to the attachment of lenses, prisms and the like.

  This invention is made | formed based on the above situations, and it aims at providing the LED module and LED lighting fixture which can enlarge the luminous intensity of a specific direction at low cost.

  As a result of intensive investigations, the present inventors have arranged the light emitting diode only on the side surface of the straight cone (or the right frustum) and have a certain length from the entire circumference of the bottom surface of the straight cone. A light emitting surface that extends and whose surface reflects or scatters at least part of the light emitted from the light emitting diode is provided. As a result, it has been found that the light emitted from the light-emitting diode is reflected or scattered by the light emitting surface, and the reflected or scattered light is incorporated into the light distribution, thereby increasing the light intensity in a specific direction, particularly in a shallow angular direction. .

  That is, an LED module according to an aspect of the present invention made to solve the above-described problem is an LED module including a plurality of light-emitting diodes, and the plurality of light-emitting diodes are a right cone, a right pyramid, a right truncated cone, or a right cone. It is disposed only on the side surface of the truncated pyramid and extends a certain length from the entire circumference of the bottom surface of the right cone, right angle pyramid, right truncated cone or right angle truncated cone, and reflects or reflects at least part of the light emitted by the light emitting diode. It has a light emitting surface that scatters.

  Furthermore, the LED lighting fixture which concerns on another aspect of this invention made | formed in order to solve the said subject is an LED lighting fixture provided with the said LED module.

  The LED module and the LED lighting fixture of the present invention can increase the luminous intensity in a specific direction at low cost, and can maintain the illuminance of the entire space uniform even when the installation density of the LED lighting fixture is low.

FIG. 1 is a schematic perspective view showing an LED module according to an embodiment of the present invention. FIG. 2 is a schematic plan view of the LED module of FIG. 1 viewed from the front surface side of the flexible printed wiring board. FIG. 3 is a schematic partial sectional view taken along line AA in FIG. FIG. 4A is a graph (light distribution curve) showing an example of directivity of the LED module in FIG. 1 when the ratio of scattered light is 0%. FIG. 4B is a graph (light distribution curve) showing an example of directivity of the LED module in FIG. 1 when the ratio of scattered light is 50%. FIG. 4C is a graph (light distribution curve) showing an example of directivity of the LED module in FIG. 1 when the ratio of scattered light is 100%. FIG. 5 is a schematic plan view in which a flexible printed wiring board on which the light emitting diode of FIG. 1 is mounted is developed on a plane. FIG. 6A is a schematic partial cross-sectional view in which the vicinity of the light emitting diode and the flexible printed wiring board of the LED module of FIG. 3 is enlarged. FIG. 6B is a schematic partial plan view of the flexible printed wiring board of FIG. 6A viewed from the front surface side. FIG. 6C is a schematic partial plan view of the flexible printed wiring board of FIG. 6A as viewed from the front side. FIG. 6D is a schematic partial cross-sectional view showing an LED module according to an embodiment different from FIG. 6A. FIG. 6E is a schematic partial cross-sectional view showing an LED module of an embodiment different from those in FIGS. 6A and 6D. FIG. 7 is a schematic front view showing a method for manufacturing the flexible printed wiring board of FIG. FIG. 8 is a schematic front view showing an LED lighting apparatus according to an embodiment of the present invention. FIG. 9A is a schematic plan view of an LED module according to an embodiment different from FIG. 1 as viewed from the front surface side of the flexible printed wiring board. FIG. 9B is a schematic side view of an LED module according to an embodiment different from FIG. 1.

[Description of Embodiment of the Present Invention]
An LED module according to an aspect of the present invention made to solve the above-described problem is an LED module including a plurality of light-emitting diodes, wherein the plurality of light-emitting diodes are a right cone, a right pyramid, a right truncated cone or a right pyramid. It is arranged only on the side surface of the stand, and extends for a certain length from the entire circumference of the bottom of the right cone, right-angle cone, right-right cone or right-angle frustum, and reflects or scatters at least part of the light emitted by the light emitting diode. A light emitting surface.

  In the LED module, a plurality of light emitting diodes are arranged only on the side surface of a right cone (right cone, right angle cone, right truncated cone or right angle frustum), and the center of the bottom surface of the right cone is centered. In all the hemispherical directions on the apex side (front side of the LED module), the uniformity of luminous intensity can be remarkably improved, and the light distribution (light distribution angle) can be increased. Further, the LED module is configured such that the light emitted from the light emitting diode is reflected or scattered by the light emitting surface, and the reflected or scattered light is incorporated into the light distribution, so that the light intensity in a specific direction, particularly in a shallow angle direction, is obtained. Can be big. That is, the LED module can increase the light intensity in a specific direction at low cost without providing a member such as a lens or a prism.

  The average angle formed by the bottom surface and the light emitting surface is preferably 0 ° or more and less than 30 °. As described above, by setting the average angle formed by the bottom surface and the light emitting surface within the above range, the light distribution angle can be increased and the luminous intensity in a specific direction can be increased.

  In the plane including the central axis of the right cone, right pyramid, right truncated cone or right frustum, the average angle formed by the straight line connecting the center of the light emitting diode and the end of the light emitting surface and the central axis is as follows: It is preferably 45 ° or more and 120 ° or less. Thus, by setting the average angle within the above range, the light distribution angle can be further increased while increasing the luminous intensity in a specific direction. Here, “the center of the light emitting diode” refers to the geometric gravity center position of the light emitting surface of the light emitting diode disposed on one side surface, and when a plurality of light emitting diodes are disposed on one side surface. , Pointing to their total geometric centroid position.

  The average extended length of the light emitting surface is preferably 3 mm or more and 150 mm or less. Thus, it is easy to ensure the luminous intensity of the reflected or scattered light by setting the average extension length of the light emitting surface within the above range. Here, the “average extension length of the light emitting surface” is defined as the outer circumference of the bottom of the right cone, right pyramid, right truncated cone or right frustum (the inner circumference of the light emitting surface) and the outer circumference of the light emitting surface. Refers to the average of the shortest distances.

  The reflectance of the light emitting surface is preferably 50% or more. Thus, by setting the reflectance of the light emitting surface to be equal to or higher than the lower limit, it is easy to increase the light intensity in a specific direction, particularly in a shallow angular direction. Here, the “reflectance” refers to the ratio of the light beam (reflected light) reflected at the reflection angle θ to the light beam incident on the boundary surface at the incident angle θ (incident light).

  The ratio of the scattered light to the entire emitted light on the light emitting surface is preferably 0% or more and 50% or less. Thus, it can prevent that the luminous intensity of a specific direction becomes too strong by making the ratio of the scattered light with respect to the whole radiation | emission light of the said light emission surface into the said range. Here, “scattered light” refers to components of the emitted light excluding reflected light.

  A right cone, right pyramid, right frustoconical or right frustum-shaped convex portion disposed in the central portion, and a light emitting plate disposed around the convex portion, the surface of which forms the light emitting surface. It is preferable that the plurality of light emitting diodes are mounted on a flexible printed wiring board, and the flexible printed wiring board is disposed at least along the convex portion of the base material. By arranging the flexible printed wiring board on which the light emitting diode is mounted on the base material having the convex portion as described above along the convex portion, the light emitting diode can be easily and surely disposed on the side surface of the straight cone. it can. Moreover, since the said base material has a light emission plate, since positioning of the said light emitting diode and a light emission plate becomes easy, the light emission surface which has suitable light distribution can be formed easily and reliably. As a result, the manufacturing cost of the LED module can be further reduced.

  The convex portion and the light radiating plate may be integrally formed. Since the convex portion and the light radiating plate are integrally formed in this way, it is difficult for the light emitting diode disposed on the convex portion and the light radiating plate to be misaligned. A light distribution is obtained.

  The convex part and the light radiating plate are preferably detachable. Thus, by making the said convex part and a light radiation plate detachable, a light radiation plate can be replaced, for example, the ratio of the scattered light with respect to the whole radiation light of a light radiation plate can be changed easily. Therefore, a suitable light distribution can be easily obtained according to the use conditions.

  The light emission surface of the light emission plate may be formed to be replaceable. Since the light emission surface can be changed in this way, the light distribution characteristic of the light emission plate can be easily changed, and a suitable light distribution can be easily obtained according to the use conditions.

  The light emitting plate may be made of metal. By making the light radiating plate made of metal in this way, the material cost of the light radiating plate is low and the processing becomes easy, so that the manufacturing cost can be reduced. Further, since the surface of the metal is easily made into a mirror surface, the reflectance of the light emitting plate can be easily increased by making the surface a mirror surface.

  The flexible printed wiring board is laminated on the surface of the base film, a conductive pattern that is laminated on the surface side of the base film, and includes one or a plurality of land portions and a wiring portion that is connected to the land portion. A cover lay having an opening formed at a position corresponding to the one or more land portions, and one or more land portions on which the light emitting diode is mounted on the back surface of the flexible printed wiring board. It is preferable to further include a heat conductive adhesive that has a recess reaching the back surface of the conductive pattern in at least a part of the projection area and is filled in the recess. Since the conductive pattern and the base material are connected through the heat conductive adhesive by filling the concave portion reaching the back surface of the conductive pattern in this way, the heat radiation effect of the light emitting diode is remarkably promoted. be able to.

  Here, the “land portion” refers to a portion in which the wiring is expanded to a size capable of solder connection in order to perform solder connection for mounting a chip component in the middle of the wiring circuit in the conductive pattern. Usually, an opening is formed at a position corresponding to this portion of the cover lay to expose the conductive portion for solder connection. When the opening is relatively small with respect to the size of the land, the entire surface of the opening becomes a circuit surface (conductive portion). On the contrary, when the opening is relatively large with respect to the size of the land portion, a pad-shaped circuit surface corresponding to the land portion and a wiring portion connected thereto may exist in the opening.

  The inclination angle of the side surface with respect to the bottom surface is preferably 55 ° or more and 82 ° or less. Thus, the light distribution angle can be further increased by setting the inclination angle of the side surface to the bottom surface within the above range.

  The direction in which the luminous intensity is maximum in the range of −90 ° to 90 ° from the reference direction to the left and right with respect to the origin and the center axis apex direction as the reference, with the base of the right cone, right cone, right cone frustum or right cone frustum as the origin. The absolute value of the angle formed from the reference direction is preferably 40 ° or more and 80 ° or less. Thus, by setting the absolute value of the angle at which the luminous intensity becomes the maximum value within the above range, it is easy to keep the illuminance of the entire space uniform when a plurality of LED modules are used. Here, “luminosity” is a value measured in accordance with JIS-C7801 (2009).

  The ratio of the maximum value of the luminous intensity in the above range to the luminous intensity in the reference direction is preferably 1 or more and 3 or less. Thus, the uniformity of the illumination intensity of the whole space at the time of using a some LED module further improves by making ratio of the maximum value of the said brightness into the said range.

  The LED lighting fixture which concerns on another aspect of this invention made | formed in order to solve the said subject is an LED lighting fixture provided with the said LED module.

  Since the LED lighting apparatus includes the LED module, the luminous intensity in a specific direction can be increased at low cost, and the illuminance of the entire space can be kept uniform when a plurality of LED lighting apparatuses are used.

  Therefore, the LED lighting apparatus can be suitably used particularly as a light bulb.

[Details of the embodiment of the present invention]
Hereinafter, embodiments of an LED module and an LED lighting apparatus according to the present invention will be described in detail with reference to the drawings. In addition, “front and back” in the embodiment of the LED module means a direction in which the light emitting diode lamination side is the front and the opposite side to the light emitting diode lamination side is the back in the thickness direction of the base film of the flexible printed wiring board, It does not mean the front and back of the LED module in use.

  The LED module 1 shown in FIGS. 1, 2 and 3 has a plurality of light emitting diodes 3 disposed only on the side surface of the right-angle frustum portion 2, and a fixed length from the entire circumference of the bottom surface of the right-angle frustum portion 2. A light emitting surface 4a that mainly extends and reflects and scatters at least part of the light emitted from the light emitting diode 3 is mainly provided. Specifically, the LED module 1 includes the plurality of light emitting diodes 3, a convex portion having substantially the same shape as that of the right-angle frustum portion 2, and the surface thereof forming the light emitting surface 4 a. A substrate 5 having a light radiating plate 4, a flexible printed wiring board 6 laminated on the surface side of the substrate 5 so as to follow the convex portion, and a heat sink 7 laminated on the back surface side of the substrate 5. Is provided.

  The right-angle frustum portion 2 is configured by a portion laminated along the convex portion of the base material 5 of the flexible printed wiring board 6, and the bottom surface (of the two surfaces facing the height direction of the right-angle frustum portion 2) , A surface having a large area) is on the substrate 5 side, and a bottom surface and an upper surface (a surface facing the bottom surface) are substantially parallel to the surface of the substrate 5. Further, the plurality of light emitting diodes 3 are disposed only in a region that forms the side surface of the right-angle frustum portion 2 on the surface of the flexible printed wiring board 6. Note that “substantially parallel” means that the angle between the normal of one surface and the other surface is within 90 ± 5 °.

<Base material>
The base material 5 is a bulk-shaped or plate-shaped member, and includes a convex portion disposed in the center portion and a light emitting plate 4 disposed around the convex portion. This convex part is substantially the same shape as the right-angle frustum part 2, and the right-angle frustum part 2 is formed by laminating | stacking the flexible printed wiring board 6 along this convex part. The light emitting plate 4 is formed as a part of the substrate 5. That is, the surface around the convex portion of the substrate 5 is a light emitting surface 4a that emits at least a part of the light emitted from the light emitting diode 3 by reflection and scattering. Furthermore, the said convex part and the light emission plate 4 are integrally molded.

  The material of the substrate 5 (the material of the light radiating plate 4) is not particularly limited as long as the surface reflects or scatters light, and examples thereof include metals, ceramics, and glass. Above all, the base material 5 is preferably made of metal or ceramics from the viewpoint of heat dissipation, and more preferably made of metal from the viewpoint that the material cost is low and the mirror finish of the surface is easy.

  As the metal of the base material 5, for example, aluminum, magnesium, copper, iron, nickel, molybdenum, tungsten, or the like can be used. Among these, aluminum is particularly preferable because it is excellent in heat conductivity, workability, and light weight and can easily obtain a mirror-like surface.

  The average thickness of the base material 5 is not limited in the case of a plate material in which a bulk material or a convex portion is not formed by press molding. The lower limit of the average thickness in the case of a plate material in which convex portions are formed by press molding is preferably 0.3 mm, and more preferably 0.5 mm. On the other hand, the upper limit of the average thickness of the substrate 5 is preferably 4 mm, and more preferably 3 mm. When the average thickness of the base material 5 is less than the above lower limit, the strength of the base material 5 may be insufficient. On the other hand, when the average thickness of the base material 5 exceeds the upper limit, it may be difficult to form a convex portion by press molding, and the weight and volume of the LED module 1 may be unnecessarily increased.

  Although the formation method of the convex part of the base material 5 is not specifically limited, It can form easily and reliably by die casting, cold forging, cutting, or press molding. For example, in the case of press molding, the base material 5 having convex portions can be formed by pressing a mold having a convex portion shape against a metal flat plate.

  Moreover, the base material 5 has a through hole 5 a through which a lead wire for connecting a power supply circuit that supplies power to the LED module 1 and the conductive pattern of the flexible printed wiring board 6 is inserted. In FIG. 1 and FIG. 2, a total of two through holes 5 a are provided on the upper surface of the convex portion, but the formation position of the through holes 5 a is not limited to this, and a connector 8 and a lead wire, which will be described later, are provided. The through hole 5a may be formed at a position where the connection is easy and where it is difficult to prevent light emission by the light emitting plate 4.

(Light emitting surface)
As described above, the light emitting surface 4 a is formed on the surface around the convex portion of the base member 5 of the LED module 1.

  The light emission surface 4a of the LED module 1 in FIG. 1 is parallel to the bottom surface of the right-angle frustum portion 2, but the light emission surface 4a is parallel to the bottom surface of the right-angle frustum portion 2 as shown in FIG. May be inclined. The lower limit of the average angle (α in FIG. 3) formed by the bottom surface of the right-angle frustum portion 2 and the light emission surface 4a is preferably 0 ° and more preferably 5 °. Moreover, as an average angle which the said bottom face and the light emission surface 4a make, less than 30 degrees is preferable and less than 20 degrees is more preferable. When the average angle formed by the bottom surface and the light emitting surface 4a is less than the lower limit, the angle at which the luminous intensity increases becomes too shallow, and the illuminance of the entire space may be insufficient. On the other hand, when the average angle formed by the bottom surface and the light emitting surface 4a exceeds the upper limit, the reflected light has an apex direction with the center of the bottom surface of the right-angle frustum portion 2 as the central axis M (hereinafter also referred to as “vertex direction”). There is a risk that the light distribution angle will be reduced.

  In a plane including the central axis M of the right-angled truncated cone part 2, an average angle (light emission) from the bottom surface side formed by the straight line connecting the center of the light emitting diode 3 and the end of the light emission surface 4a and the center axis M. The average angle of the surface 4a) (β in FIG. 3) is preferably 45 °, more preferably 60 °, and still more preferably 80 °. Further, the upper limit of the average angle of the light emitting surface 4a is preferably 120 °, more preferably 90 °. When the average angle of the light emitting surface 4a is less than the lower limit, the angle of the light emitting surface 4a is too shallow with respect to the normal direction of the light emitting surface of the light emitting diode 3, and the light emitted from the light emitting diode 3 is insufficient. There is a risk. On the other hand, when the average angle of the light emitting surface 4a exceeds the above upper limit, light emitted from the light emitting diode 3 in a shallow angle direction is shielded by the reflection of the light emitting plate 4, and the light distribution angle may be reduced.

  The outer shape of the light emitting surface 4a (planar shape of the base material 5) is not particularly limited, but a circular shape or a shape similar to the shape of the bottom surface is preferable. Thus, by making the outer shape of the light radiating plate 4 the above shape, the illuminance distribution is unlikely to have anisotropy, so the uniformity of the illuminance in the entire space can be improved.

  The lower limit of the average extension length of the light emitting surface 4a is preferably 3 mm, and more preferably 5 mm. Moreover, as an upper limit of the average extension length of the light emission surface 4a, 150 mm is preferable and 100 mm is more preferable. When the average extension length of the light emitting surface 4a is less than the lower limit, the luminous intensity of the reflected light may be insufficient. On the other hand, when the average extension length of the light emitting surface 4a exceeds the above upper limit, the occupied area of the LED lighting apparatus using the LED module 1 becomes too large, and the handling may be difficult.

  The light emitting surface 4a has reflectivity or light scattering properties. When the light emitting surface 4a has reflectivity, the light emitted from the light emitting diode 3 and reaching the light emitting surface 4a is reflected by the light emitting surface 4a at a reflection angle equal to the incident angle, and is emitted from the light emitting diode 3 to the light emitting surface 4a. It is emitted together with the direct light that is emitted directly without being reflected. For this reason, the luminous intensity in the reflection angle direction is enhanced. Since the light emitting surface 4a is disposed on the bottom surface side of the right-angle frustum portion 2, the reflection angle direction is a shallow angle direction, and in particular, the light intensity at a shallow angle can be increased.

  The lower limit of the reflectance of the light emitting surface 4a is preferably 50%, more preferably 60%. Further, the upper limit of the reflectance is not particularly limited, but may be 100%, for example. When the reflectance is less than the lower limit, the light intensity in the shallow angular direction cannot be sufficiently increased, and the illuminance distribution in the entire space may not be uniformized sufficiently.

  In addition, in order to provide reflectivity to the light emitting surface 4a and increase the reflectance, the surface of the light emitting plate 4 is preferably a mirror surface. In order to obtain a mirror-like surface, for example, a method of cutting a metal plate, a method of polishing after the cutting, a method of vapor-depositing metal, and the like can be mentioned.

  When the light radiating plate 4 has light scattering properties, the light incident on the light radiating plate 4 follows a Lambertian distribution by Lambertian scattering. Therefore, the light intensity in the apex direction tends to be increased. As described above, since the light emitting plate 4 has light scattering properties, it is possible to prevent the illuminance distribution in the entire space from being deteriorated due to excessively high light intensity in a specific direction, particularly in a shallow angle direction.

  As an upper limit of the ratio of the scattered light with respect to the whole radiation light of the light radiation plate 4, 50% is preferable and 40% is more preferable. Moreover, it does not specifically limit as a minimum of the ratio of the scattered light with respect to the whole radiated light of the light radiation board 4, It may be 0%. By setting the ratio of the scattered light to the entire radiation light of the light radiation plate 4 within the above range, the light intensity in the shallow angle direction becomes strong as shown in FIGS. 4A and 4B, and the light intensity toward the apex direction is also appropriately maintained. it can. On the other hand, when the ratio of the scattered light to the whole radiated light of the light radiating plate 4 exceeds the upper limit, as shown in FIG. 4C, the light intensity in the shallow angle direction becomes weak and the light intensity in the normal direction becomes relatively strong. There is a fear. The ratio of the scattered light can be changed by changing the material of the light radiating plate 4 or the roughness of the mirror surface.

  4A, FIG. 4B, and FIG. 4C are the polar coordinates of the LED module 1 in which the ratio of scattered light is 0% in FIG. 4A, 50% in FIG. 4B, and 100% in FIG. It is the graph relatively represented by the system. The LED module 1 has a light emitting diode having a height of 10 mm, one on each side of a regular hexagonal frustum having an inclination angle of 69 ° with respect to the bottom surface to be described later, a total of six from the bottom of the regular hexagonal frustum at the center of the light emitting diode. The height was set to 5 mm. The light emitting surface had an average extension length of 15 mm, and the average angle between the bottom surface of the regular hexagonal frustum and the light emitting surface was 0 °. The graph in each figure has shown the value which averaged the light intensity of the range of -90 degrees to 90 degrees right and left from a reference direction in the perimeter of the central axis of a right-angled frustum. The concentric circles in this graph are graduations obtained by dividing the relative intensity of light intensity every 10%, and indicate that the light intensity increases toward the outside.

<Flexible printed wiring board>
As shown in FIGS. 5A and 6A, the flexible printed wiring board 6 includes a base film 6a having flexibility and insulation, a conductive pattern 6b laminated on the surface side of the base film 6a, a base film 6a, and a conductive pattern. And a coverlay 6e laminated on the surface of 6b. The conductive pattern 6b has a plurality of land portions 6c and a wiring portion 6d connected to the land portions 6c, and the light emitting diode 3 is electrically connected to the land portions 6c through solder 3a. It is arranged (mounted) as follows. The coverlay 6e has openings formed at positions corresponding to the plurality of land portions 6c. Note that FIG. 5A shows a planar development view before the flexible printed wiring board 6 is laminated along the convex portion of the substrate 5. For ease of viewing, the coverlay 6e is omitted in FIG. 5A.

(Base film)
The base film 6a which comprises the said flexible printed wiring board 6 is comprised with the sheet-like member which has insulation and flexibility. Specifically, a resin film can be used as the sheet-like member constituting the base film 6a. As the main component of this resin film, for example, polyimide, polyethylene terephthalate or the like is preferably used. The base film 6a may include a filler, an additive, and the like. Here, “main component” means a component contained in an amount of 50% by mass or more.

  As shown in FIG. 5A, the base film 6a has a planar shape in which a plurality of trapezoids of the same shape are joined so that each side of the regular polygon and the upper side are shared, and only in the plurality of trapezoidal portions. A light emitting diode 3 is mounted. The base film 6a is bent at the connection side of the regular polygon and each trapezoid so as to follow the convex part of the base material 5, and the regular polygon part is laminated on the upper surface of the convex part of the base material 5, and the side surface of the convex part Each trapezoidal portion is stacked on the substrate. A connector 8 described later is mounted on the upper surface of the base film 6a. Furthermore, the base film 6 a has a through hole 9 through which a lead wire is inserted at a position corresponding to the through hole 5 a of the convex portion of the base material 5.

  In addition, when the base film 6a is arrange | positioned along the convex part of the base material 5, it is preferable to have a shape where the hypotenuses of an adjacent trapezoid part contact | abut. Thus, by making the base film 6a into a shape in which the hypotenuses of the trapezoidal portions come into contact with each other, it is possible to prevent the surface of the base material 5 from appearing in the right-angled frustum portion 2, and the luminous intensity of the LED module 1 can be reduced. Uniformity and design can be improved.

  As a minimum of average thickness of the above-mentioned base film 6a, 9 micrometers is preferred and 12 micrometers is more preferred. Moreover, as an upper limit of the average thickness of the base film 6a, 50 micrometers is preferable and 38 micrometers is more preferable. When the average thickness of the base film 6a is less than the above lower limit, the strength of the base film 6a may be insufficient. On the other hand, when the average thickness of the base film 6a exceeds the upper limit, it may be difficult to bend the base film 6a into a straight cone shape along the convex portion.

(Conductive pattern)
The conductive pattern 6b has a plurality of land portions 6c and wiring portions 6d connected to the land portions 6c. A desired planar shape (pattern) is obtained by etching a metal layer laminated on the surface of the base film 6a. Is formed. One set of land portions 6c is provided on each trapezoidal portion of the base film 6a (unit on which one light-emitting diode 3 can be mounted), and the light-emitting diodes 3 are mounted on the respective land portions 6c. The wiring portion 6d is formed so as to connect the plurality of land portions 6c and the connector 8 in series.

  The conductive pattern 6b can be formed of a conductive material, but is generally formed of copper, for example.

  The lower limit of the average thickness of the conductive pattern 6b is preferably 5 μm, and more preferably 8 μm. Moreover, as an upper limit of the average thickness of the conductive pattern 6b, 75 micrometers is preferable and 50 micrometers is more preferable. When the average thickness of the conductive pattern 6b is less than the above lower limit, the conductivity may be insufficient. On the other hand, when the average thickness of the conductive pattern 6b exceeds the upper limit, the flexibility of the flexible printed wiring board 6 may be impaired.

(Adhesive layer)
The flexible printed wiring board 6 further includes an adhesive layer 6h laminated on the back surface of the base film 6a, and is adhered to the base material 5 by the adhesive layer 6h. The adhesive layer 6 h is a layer mainly composed of an adhesive capable of bonding the base film 6 a to the base material 5. The adhesive is not particularly limited, and for example, a thermosetting adhesive such as an epoxy adhesive, a silicone adhesive, and an acrylic adhesive can be used. The adhesive layer 6h can contain an additive as necessary. However, since the LED module 1 includes thermal conductive adhesive layers 11a and 11b described later, it is not necessary to impart thermal conductivity to the adhesive layer 6h.

  The lower limit of the average thickness of the adhesive layer 6h is preferably 5 μm, and more preferably 10 μm. Moreover, as an upper limit of the average thickness of the adhesive bond layer 6h, 50 micrometers is preferable and 25 micrometers is more preferable. When the average thickness of the adhesive layer 6h is less than the above lower limit, the adhesive strength between the flexible printed wiring board 6 and the substrate 5 may be insufficient. On the other hand, if the average thickness of the adhesive layer 6h exceeds the above upper limit, the LED module 1 may be unnecessarily thick, or the distance between the conductive pattern 6b and the substrate 5 may be increased. There is a risk that the heat dissipation will be insufficient.

  In the adhesive layer 6h, an opening is formed that defines a back side portion of the recess 10 filled with heat conductive adhesive layers 11a and 11b described later. The size of the opening of the back side portion, that is, the back side portion of the concave portion 10 in the adhesive layer 6h is larger than the size of the opening of the front side portion of the concave portion 10, that is, the base film 6a described later. Thus, the filling operation of the heat conductive adhesive layers 11a and 11b can be facilitated by increasing the opening of the recess 10 in the adhesive layer 6h. Further, when the adhesive film 6h having an opening for defining the back side portion of the concave portion 10 is formed after the base film 6a is removed and the front side portion of the concave portion 10 is formed, these positions are easily aligned.

(Concave)
The LED module 1 has a concave portion 10 that reaches the back surface of the conductive pattern 6b in at least a part of the projected area of the plurality of land portions 6c on which the one light emitting diode 3 is mounted among the back surface of the flexible printed wiring board 6. Further, as shown in FIG. 6B, a peripheral edge L2 facing the connection edge L1 of the plurality of land portions 6c with the wiring portion 6d in a plan view substantially perpendicular to the surface of the flexible printed wiring board 6 in the recess 10 as shown in FIG. The base film 6a remains in the remaining region P including This remaining area P is also an area between the pair of land portions 6c. By leaving the base film 6a in this way, when the flexible printed wiring board 6 is attached to the base material 5, the peripheral edge L2 of the land portion 6c facing the connecting edge L1 with the wiring portion 6d is pressed to be flexible printed wiring. Even if it falls to the back surface side of the plate 6, a short circuit between the land portion 6 c and the base material 5 can be prevented by the base film 6 a in the remaining region P. In addition, illustration of the coverlay 6e is abbreviate | omitted in FIG. 6B. The “connection edge with the wiring part” means the boundary line between the wiring part and the land part, and the “periphery opposite to the connection edge with the wiring part” means the edge of the land part on the connection edge. And a virtual straight line passing through the geometric center of gravity of the land portion intersects.

  The recess 10 is formed in a region overlapping the projection region of the light emitting diode 3 mounted on the land portion 6c located on the bottom surface. That is, the front side portion of the concave portion 10 is formed by removing the base film 6 a in the region covering the projection region of the light emitting diode 3 except for the remaining region P. Moreover, the back side part of the recessed part 10 is formed in the area | region which covers the projection area | region of a front side part. Thereby, as described above, the opening of the recess 10 is stepwise in the thickness direction so as to be large at the position of the adhesive layer 6h on the back side (back side portion) and small at the position of the base film 6a on the front side (front side portion). The diameter has been expanded.

  In the flexible printed wiring board 6 of FIGS. 5A and 6A, the projected areas of the plurality of land portions 6c all overlap with the opening area (including the front side portion and the remaining area P) of the recess 10 in the base film 6a in plan view. However, as long as the heat transfer promoting effect of the present invention is achieved, a part of the projected area of the land portion 6c may not overlap the opening area of the recess 10 in the base film 6a. The lower limit of the ratio of the overlapping area (excluding the remaining region P) of the concave portion 10 and the land portion 6c in the base film 6a to the total area of the land portion 6c is preferably 80%, more preferably 90%, and 95%. Further preferred. When the said area ratio is less than the said minimum, there exists a possibility that the heat transfer effect of the said LED module 1 may become inadequate.

  Further, in the flexible printed wiring board 6 of FIG. 6A, at least the front side portion of the recess 10 is formed in a region covering at least the projection region of the opening H of the cover lay 6e provided at a position corresponding to the plurality of land portions 6c. ing. Further, at least the front side portion of the recess 10 is formed in a region covering at least the projection region of the light emitting diode 3, and a cover layout is provided between the plurality of land portions 6 c in a plan view substantially perpendicular to the surface of the flexible printed wiring board 6. 6e exists. Note that the projection area of the opening H of the coverlay 6e of the flexible printed wiring board 6 of FIG. 6A is smaller than the projection area of the land portion 6c as shown in FIG. 6C, and exists within the projection area of the land portion 6c. That is, a part of the land portion 6 c is exposed by the opening H.

  The upper limit of the opening area of the recess 10 in the base film 6a is preferably twice the projected area of the light emitting diode 3, more preferably 1.8 times, and even more preferably 1.5 times. When the opening area of the recess 10 in the base film 6a exceeds the above upper limit, the removal region of the base film 6a becomes large, and there is a possibility that the insulation reliability becomes insufficient when the flexible printed wiring board 6 is bent. The “opening area of the recess” means the area of the bottom surface of the recess (the conductive pattern or the exposed back surface of the coverlay) and does not include the area of the remaining region P.

  The lower limit of the difference between the opening diameter of the recess 10 in the base film 6a (the diameter of the front portion) and the opening diameter of the recess 10 in the adhesive layer 6h (the diameter of the back portion) is preferably 2 μm, more preferably 40 μm, and 100 μm. Is more preferable. Moreover, as an upper limit of the difference of the opening diameter of the recessed part 10 in the base film 6a, and the opening diameter of the recessed part 10 in the adhesive bond layer 6h, 1000 micrometers is preferable, 600 micrometers is more preferable, and 200 micrometers is further more preferable. When the difference between the opening diameter of the recess 10 in the base film 6a and the opening diameter of the recess 10 in the adhesive layer 6h is less than the lower limit, the filling operation of the heat conductive adhesive layers 11a and 11b is not sufficiently facilitated. There is a risk. On the other hand, when the difference between the opening diameter of the recess 10 in the base film 6a and the opening diameter of the recess 10 in the adhesive layer 6h exceeds the upper limit, the filling amount of the heat conductive adhesive layers 11a and 11b increases, and the LED There is a possibility that the cost of the module 1 may become unnecessarily large and the adhesive strength to the substrate 5 may be lowered. The “opening diameter” means the diameter of a perfect circle having the same area as the opening.

  As a lower limit of the average overlap width W between the projected area (residual area P) of the remaining portion of the base film 6a and the projected area of the one land portion 6c (one of the left or right land portions 6c in FIG. 6A), 10 μm is preferable, 30 μm is more preferable, and 50 μm is further preferable. Moreover, as an upper limit of the said average overlap width W, 500 micrometers is preferable, 300 micrometers is more preferable, and 100 micrometers is more preferable. When the average overlap width W is less than the lower limit, the short-circuit preventing effect between the land portion 6c and the base material 5 may be insufficient. On the other hand, when the said average overlap width W exceeds the said upper limit, there exists a possibility that the thermal radiation effect by the recessed part 10 and the heat conductive adhesive layers 11a and 11b may become inadequate. The “average overlap width” is the length of a portion overlapping the projection region of the remaining portion of the base film 6a in the periphery of the projection region of the land portion 6c, and is the length of the land portion 6c and the remaining portion of the base film 6a. It means a value obtained by dividing the area of the overlapping portion of the projection area.

(Thermal conductive adhesive layer)
The LED module 1 includes thermally conductive adhesive layers 11a and 11b. The heat conductive adhesive layers 11 a and 11 b are filled in the recess 10 and adhere the conductive pattern 6 b and the substrate 5. Specifically, the heat conductive adhesive layers 11a and 11b are laminated on the back surface of the conductive pattern 6b, and the first heat conductive adhesive layer 11a filled on the front surface side of the recess 10 and the first heat conductive adhesive layer 11a and 11b. It consists of the 2nd heat conductive adhesive layer 11b laminated | stacked on the back surface of the conductive adhesive layer 11a, and being filled in the back surface side of the recessed part 10. FIG. After forming the first layer (first heat conductive adhesive layer 11a) by forming the heat conductive adhesive layers 11a and 11b in two layers in this manner, the presence or absence of voids is confirmed. Since the second layer (second heat conductive adhesive layer 11b) can be formed, it is possible to prevent a decrease in thermal conductivity and adhesive force by ensuring the filling of the adhesive.

  The heat conductive adhesive layers 11a and 11b contain an adhesive resin component and a heat conductive filler, respectively.

  Examples of the adhesive resin component that can be used include polyimide, epoxy, alkyd resin, urethane resin, phenol resin, melamine resin, acrylic resin, polyamide, polyethylene, polystyrene, polypropylene, polyester, vinyl acetate resin, silicone resin, and rubber. If an adhesive mainly composed of an acrylic resin, a silicone resin, a urethane resin, or the like is used as the adhesive resin component, the flexible printed wiring board 6 can be easily and reliably attached to the base material 5.

  Examples of the heat conductive filler include metal oxides and metal nitrides. As the metal oxide, aluminum oxide, silicon oxide, beryllium oxide, magnesium oxide, or the like can be used. Among these, aluminum oxide is preferable from the viewpoint of electrical insulation, thermal conductivity, price, and the like. As the metal nitride, aluminum nitride, silicon nitride, boron nitride, or the like can be used. Among these, boron nitride is preferable from the viewpoint of electrical insulation, thermal conductivity, and low dielectric constant. In addition, the said metal oxide and metal nitride can be used in mixture of 2 or more types.

  As a minimum of content of a heat conductive filler in heat conductive adhesive layers 11a and 11b, 40 volume% is preferred and 45 volume% is more preferred. Moreover, as an upper limit of content of a heat conductive filler, 85 volume% is preferable and 80 volume% is more preferable. When content of a heat conductive filler is less than the said minimum, there exists a possibility that the heat conductivity of the heat conductive adhesive layers 11a and 11b may become inadequate. On the other hand, when content of a heat conductive filler exceeds the said upper limit, it becomes easy to enter a bubble at the time of mixing the said adhesive resin component and a heat conductive filler, and there exists a possibility that withstand voltage may fall. In addition, the heat conductive adhesive layers 11a and 11b may contain additives such as a curing agent in addition to the heat conductive filler.

  As a minimum of thermal conductivity of heat conductive adhesive layers 11a and 11b, 1 W / mK is preferred and 1.5 W / mK is more preferred. Moreover, as an upper limit of the heat conductivity of the heat conductive adhesive layers 11a and 11b, 20 W / mK is preferable. When the thermal conductivity of the heat conductive adhesive layers 11a and 11b is less than the lower limit, the heat dissipation effect of the LED module 1 may be insufficient. On the other hand, when the thermal conductivity of the heat conductive adhesive layers 11a and 11b exceeds the above upper limit, the content of the heat conductive filler becomes excessive, and bubbles enter during mixing of the adhesive resin component and the heat conductive filler. There is a risk that the withstand voltage may be reduced and the cost may be excessive.

  The thermal conductivity of the second thermally conductive adhesive layer 11b is preferably smaller than the thermal conductivity of the first thermally conductive adhesive layer 11a. In other words, the content of the heat conductive filler in the second heat conductive adhesive layer 11b is preferably smaller than the content of the heat conductive filler in the first heat conductive adhesive layer 11a. Thus, while increasing the heat conductive filler content of the 1st heat conductive adhesive layer 11a, and reducing the heat conductive filler content of the 2nd heat conductive adhesive layer 11b, heat conductive adhesion The adhesive force with the base material 5 can be enhanced while maintaining the heat dissipation effect in the entire agent layer.

  Moreover, it is preferable that the thixotropy (thixotropy) of the adhesive forming the first thermally conductive adhesive layer 11a is higher than the thixotropic property of the adhesive forming the second thermally conductive adhesive layer 11b. By increasing the thixotropy of the adhesive of the first heat conductive adhesive layer 11a as compared to the second heat conductive adhesive layer 11b, the filling property of the adhesive into the concave portion 10 can be improved, and the first can be more easily and reliably performed. One heat conductive adhesive layer 11a can be formed. The thixotropy is an index of the property that the viscosity decreases when a certain force is applied and recovers to the original viscosity when left standing, for example, the viscosity at a low shear rate is divided by the viscosity at a high shear rate. It is expressed as a ratio.

The heat conductive adhesive layers 11a and 11b are preferably highly insulating. Specifically, the lower limit of the volume resistivity of the heat conductive adhesive layers 11a and 11b is preferably 1 × 10 ⁸ Ωcm, and more preferably 1 × 10 ¹⁰ Ωcm. When the volume resistivity of the heat conductive adhesive layers 11a and 11b is less than the lower limit, the insulating properties of the heat conductive adhesive layers 11a and 11b are lowered, and the conductive pattern 6b is laminated on the back side of the base film 6a. There is a possibility that the substrate 5 is electrically connected. The volume resistivity is a value measured according to JIS-C2139 (2008).

  The average thickness of the entire heat conductive adhesive layers 11a and 11b (the average distance from the back surface of the second heat conductive adhesive layer 11b to the back surface of the conductive pattern 6b) is equal to the average thickness of the base film 6a and the adhesive layer 6h. It is preferable that it is larger than the sum of the average thicknesses. Specifically, the lower limit of the average thickness of the entire heat conductive adhesive layers 11a and 11b is preferably 5 μm, and more preferably 10 μm. Moreover, as an upper limit of the average thickness of the whole heat conductive adhesive layer 11a, 11b, 100 micrometers is preferable and 50 micrometers is more preferable. When the average thickness of the entire heat conductive adhesive layers 11a and 11b is less than the lower limit, the heat conductive adhesive layers 11a and 11b are sufficiently brought into contact with the base material 5 laminated on the back side of the base film 6a. Therefore, the heat transfer effect may be insufficient. On the other hand, when the average thickness of the whole heat conductive adhesive layers 11a and 11b exceeds the above upper limit, the filling amount of the heat conductive adhesive layers 11a and 11b may increase and the cost may increase, and the LED module 1 is unnecessary. May become thicker.

  The lower limit of the ratio of the average thickness of the second heat conductive adhesive layer 11b to the average thickness of the first heat conductive adhesive layer 11a is preferably 0.1, and more preferably 0.2. Moreover, as an upper limit of ratio of the average thickness of the 2nd heat conductive adhesive layer 11b with respect to the average thickness of the 1st heat conductive adhesive layer 11a, 2 is preferable and 1.5 is more preferable. When the ratio of the average thickness of the second heat conductive adhesive layer 11b to the average thickness of the first heat conductive adhesive layer 11a is less than the above lower limit, the effect of improving the adhesiveness may be insufficient. On the other hand, when the ratio of the average thickness of the second heat conductive adhesive layer 11b to the average thickness of the first heat conductive adhesive layer 11a exceeds the above upper limit, the heat dissipation effect may be insufficient.

(Coverlay)
A coverlay 6e is laminated on a portion of the surface of the flexible printed wiring board 6 excluding a portion where the light emitting diode 3 is mounted (land portion 6c). The coverlay 6e has an insulating function and an adhesive function, and is adhered to the surfaces of the base film 6a and the conductive pattern 6b. When the coverlay 6e has the insulating layer 6f and the adhesive layer 6g as shown in FIG. 6A, the insulating layer 6f can be made of the same material as the base film 6a, and the average thickness is the same as that of the base film 6a. be able to. Moreover, as an adhesive which comprises the adhesive layer 6g of the coverlay 6e, an epoxy-type adhesive agent etc. are used suitably, for example. The average thickness of the adhesive layer 6g is not particularly limited, but is preferably 12.5 μm or more and 25 μm or less.

  The surface of the coverlay 6e is preferably colored white. By forming a white layer on the surface of the cover lay 6e, the light emitted from the light emitting diode 3 is reflected or scattered and further reflected or scattered to the flexible printed wiring board 6 side. Can be increased. Moreover, the designability of the LED module 1 can be improved. This white layer can be formed, for example, by applying a white pigment-containing paint.

(connector)
Connectors 8 are connected to both ends of the conductive pattern 6b. The connector 8 is a member for electrically connecting the plurality of light emitting diodes 3 to a power supply circuit that supplies power to the LED module 1, and is mounted on the land portion 6c of the conductive pattern 6b. The connector 8 is connected to a lead wire penetrating the through hole 5 a and supplies lighting power to the light emitting diode 3.

<Right-angle frustum part>
The right-angle frustum portion 2 is a right-angle frustum-shaped portion whose bottom surface is a regular polygon. The lower limit of the inclination angle (θ in FIG. 3) with respect to the bottom of the side surface of the right-angle frustum portion 2 is preferably 55 °, more preferably 60 °, still more preferably 65 °, and particularly preferably 68 °. Moreover, as an upper limit of the inclination | tilt angle with respect to the bottom face of the side surface of the right-angle frustum part 2, 82 degrees is preferable, 80 degrees is more preferable, 75 degrees is further more preferable, and 74 degrees is especially preferable. When the tilt angle is less than the lower limit, the light intensity in the shallow angle direction is greatly reduced with respect to the light intensity in the apex direction on the surface side of the flexible printed wiring board 6 (the protruding side of the right-angle frustum portion 2), and the illuminance distribution There is a risk that the homogenization will be insufficient. When the tilt angle exceeds the upper limit, the light intensity in the apex direction is greatly reduced with respect to the light intensity in the shallow angle direction on the surface side of the flexible printed wiring board 6, and there is a risk that the illuminance distribution is not sufficiently uniform. .

  The bottom surface of the right-angle frustum portion 2 is a regular hexagon in FIGS. 1 and 2, but the shape of the bottom surface of the right-angle frustum portion 2 of the LED module 1 is not limited to a regular hexagon. However, the bottom surface of the right-angle frustum portion 2 is preferably a regular polygon, and the number of corners of the bottom surface is preferably an odd number. When the number of corners on the bottom surface is an odd number, the uniformity of luminous intensity can be improved more effectively.

  The lower limit of the number of corners of the regular polygon on the bottom surface is preferably 5 corners, more preferably 7 corners. In addition, the upper limit of the number of corners of the regular polygon on the bottom surface is not particularly limited, but 50 corners are preferable. If the number of regular polygons on the bottom surface is less than the lower limit, the illuminance distribution may be insufficiently uniform. On the other hand, when the number of corners of the regular polygon on the bottom surface exceeds the above upper limit, the side area of the right-angle frustum portion 2 becomes small, and it may be difficult to dispose the light emitting diode 3.

  In addition, as the shape of the bottom surface of the right-angle frustum portion 2, it is also possible to adopt a pentagon or the like in which the lengths of the respective sides are different. In order to effectively suppress fluctuations in luminous intensity, the shape of the bottom surface of the right-angle frustum portion 2 is preferably a regular polygon, but the effect can be obtained even with polygons having different lengths on each side.

  The dimension of the right-angle frustum part 2 is not specifically limited, It can design suitably according to the illumination intensity, magnitude | size, etc. of the lighting fixture which uses the said LED module 1. FIG. The diameter of the circumscribed circle on the bottom surface of the right-angle frustum portion 2 can be, for example, 10 mm or more and 300 mm or less. The diameter of the circumscribed circle on the upper surface of the right-angle frustum portion 2 can be, for example, 1 mm or more and 30 mm or less. The height of the right-angle frustum portion 2 can be, for example, 5 mm or more and 40 mm or less.

<Light emitting diode>
The light emitting diode 3 is mounted on the land portion 6c of the flexible printed wiring board 6 via the solder 3a. As the light-emitting diode 3, a multi-color light-emitting type or a single-color light-emitting type, and a surface-mounted light-emitting diode packaged with a chip type or a synthetic resin can be used. Moreover, it is preferable to use the light emitting diode which is not provided with the lens from a viewpoint of improving the effect of this invention. That is, in the LED module 1, it is preferable to use a light emitting diode whose luminous intensity distribution shows a Lambertian distribution. The connection method of the light emitting diode 3 to the land portion 6c is not limited to solder, and for example, die bonding using a conductive paste, wire bonding using a metal wire, or the like can be used.

  The plurality of light emitting diodes 3 are disposed only on the side surface of the right-angle frustum portion 2 and are not disposed on the upper surface of the right-angle frustum portion 2. The plurality of light emitting diodes 3 are arranged so that the light emitting surfaces are substantially parallel to the side surfaces of the right-angle frustum portion 2.

  It is preferable that the angles formed by the projection lines on the bottom surface of the right-angle frustum portion 2 of the normal line of the light emitting surface of the adjacent light emitting diodes 3 (the angle between the adjacent light emitting diodes 3) are all equal. ° is preferred. Thus, when the angle between the adjacent light emitting diodes 3 is different, or when the angle exceeds the upper limit, the illuminance distribution has anisotropy and the uniformity may be insufficient.

  The number of light emitting diodes 3 disposed on each side surface of the right-angle frustum portion 2 is 1 in FIGS. 1 to 4, but the number of light emitting diodes 3 is the illuminance and size of the lighting fixture using the LED module 1. It can design suitably according to etc., and it is good also as 2 or more. In addition, it is preferable that the number of the light emitting diodes 3 arranged on each side is the same so that anisotropy of the illuminance distribution is suppressed.

  The light emitting diodes 3 are preferably arranged at the same position on each side surface of the right-angle frustum portion 2. Thus, by arranging the light emitting diodes 3 at the same positions on the respective side surfaces, the light emitting diodes 3 can be arranged at equal intervals in the circumferential direction, so that anisotropy of the illuminance distribution can be suppressed.

<Heatsink>
The heat sink 7 is a heat radiating member laminated on the back surface side of the base material 5. The heat sink 7 is a hollow or solid columnar member and has a bottom surface similar to the planar shape of the substrate 5.

  The material of the heat sink 7 is not particularly limited as long as it has high heat conductivity, but aluminum can be suitably used from the viewpoint of light weight and workability. Moreover, although the heat sink 7 can be manufactured by machining a metal plate or a metal block, it is preferable to use a metal plate from the viewpoint of cost.

  In addition, since the base material 5 itself has a certain heat dissipation function, the heat sink 7 can be omitted.

  As a minimum of average thickness of heat sink 7, 0.3 mm is preferred and 0.5 mm is more preferred. Moreover, as an upper limit of the average thickness of the heat sink 7, 10 mm is preferable and 8 mm is more preferable. When the average thickness of the heat sink 7 is less than the above lower limit, the heat dissipation effect may be insufficient. On the other hand, when the average thickness of the heat sink 7 exceeds the upper limit, the weight and volume of the LED module 1 may become unnecessarily large.

<Directivity of LED module>
The angle formed from the reference direction in the direction in which the luminous intensity is maximum in the range of −90 ° to 90 ° from the reference direction to the left and right with respect to the center of the bottom surface of the right-angle frustum portion 2 as the origin and the center axis vertex direction. The lower limit of the absolute value (maximum luminous intensity direction) is preferably 40 °, more preferably 45 °. Moreover, as an upper limit of the said maximum luminous intensity direction, 80 degrees is preferable and 75 degrees is more preferable. When the maximum luminous intensity direction is less than the lower limit, the tendency of reflected light toward the apex direction is increased, and the light distribution angle may be reduced. On the other hand, when the maximum luminous intensity direction exceeds the upper limit, the angle at which the luminous intensity becomes strong becomes too shallow, and the overall illuminance may be insufficient.

  The lower limit of the ratio (maximum luminous intensity ratio) of the maximum luminous intensity in the above range to the luminous intensity in the reference direction is preferably 1. The upper limit of the maximum luminous intensity ratio is preferably 3, and more preferably 2. When the maximum luminous intensity ratio is less than the lower limit, the intensity of light in the maximum luminous intensity direction is relatively insufficient, so when using a plurality of LED modules having the maximum luminous intensity direction in a shallow angular direction, the entire space The illuminance distribution may not be uniform. On the other hand, when the maximum luminous intensity ratio exceeds the upper limit, the illuminance distribution may be insufficiently uniform due to the unbalanced luminous intensity.

<Manufacturing method of LED module>
For example, as shown in FIG. 7, the LED module 1 includes a step of forming a light emitting surface 4 a that reflects or scatters light of the light emitting diode 3 on the surface around the convex portion of the base material 5, and a surface of the base material 5. It can be manufactured by a manufacturing method including a step of laminating the flexible printed wiring board 6 along the convex portion on the side and a step of laminating the heat sink 7 on the back surface side of the substrate 5. Note that either the laminating step of the flexible printed wiring board 6 or the laminating step of the heat sink 7 may be performed first or simultaneously.

  As a method of forming the light emitting surface 4a on the surface around the convex portion of the base material 5, for example, when a metal plate is used for the base material 5, a method of obtaining a mirror-like surface by cutting is mentioned. Further, polishing may be performed after cutting.

  As a method for laminating the flexible printed wiring board 6 on the base material 5, for example, a method having the following steps can be used. First, a hole defining the front side portion of the recess 10 is formed in the base film 6a, and an adhesive sheet having a hole defining the back side portion of the recess 10 is laminated on the back surface of the base film 6a. Next, the recess 10 is filled with a heat conductive adhesive. Then, the flexible printed wiring board 6 is laminated | stacked on the surface of the base material 5, and these are adhere | attached.

  Examples of the method of laminating the heat sink 7 on the base material 5 include a method of fixing both with a screw and a method of bonding them together with an adhesive, but fixing with a screw from the viewpoint of ensuring heat conductivity. The method is preferred.

<Advantages>
The LED module 1 has a plurality of light-emitting diodes 3 arranged only on the side surface of the right-angle frustum portion 2, so that the hemispherical omnidirectional (on the apex side around the center of the bottom surface of the right-angle frustum portion 2 ( On the front side of the LED module 1, the uniformity of luminous intensity can be significantly improved, and the light distribution (light distribution angle) can be increased. Further, the LED module 1 is configured such that light emitted from the light emitting diode 3 is reflected or scattered by the light radiating plate 4, and the reflected or scattered light is incorporated into the light distribution so that a specific direction, particularly a shallow angular direction, is obtained. The brightness of can be increased. That is, the LED module 1 can increase the luminous intensity in a specific direction at low cost without providing a member such as a lens or a prism.

  In addition, the flexible printed wiring board 6 on which the light emitting diode 3 is mounted is disposed along the convex portion on the base material 5 having the convex portion, so that the light emitting diode 3 can be easily and reliably attached to the side surface of the right-angle frustum portion 2. It can be arranged. Further, since the substrate 5 includes the light emitting plate 4, the light emitting diode 3 and the light emitting plate 4 can be easily positioned, and the light emitting surface 4a having a suitable light distribution can be easily and reliably formed. . As a result, the manufacturing cost of the LED module 1 can be further reduced.

  Furthermore, since the LED module 1 is connected to the conductive pattern 6b and the substrate 5 via the heat conductive adhesive by filling the concave portion 10 reaching the back surface of the conductive pattern 6b with the heat conductive adhesive, The heat dissipation effect of the light emitting diode 3 can be significantly promoted.

[LED lighting equipment]
Next, an LED lighting apparatus using the LED module 1 will be described. The LED lighting apparatus of FIG. 8 is a high-output LED lighting apparatus that is used by being installed on a high ceiling of a gymnasium or factory, for example. The LED lighting apparatus mainly includes the LED module 1, a heat dissipation space 21, a housing 22, and a base 23. The LED lighting apparatus of FIG. 8 shows the orientation when the LED mounting surface is installed on the ceiling so that the LED mounting surface faces downward, for example, the LED module 1 is provided at the bottom, the LED 3 is at the bottom, and the heat sink 7 Is arranged so as to be on the upper side. The heat sink 7 is preferably formed with fins to increase the surface area in order to improve heat dissipation.

  The heat radiation space 21 is located above the heat sink 7 of the LED module 1 and is a space for discharging the heat from the heat sink 7 and not transferring the heat to the housing 22 side. In order to make it more difficult to transfer heat to the housing 22 side, for example, a plurality of disk-shaped heat radiating plates may be disposed in the heat radiating space 21 in an overlapping manner.

  The housing 22 is located above the heat dissipation space 21 and houses a power supply circuit and its control circuit. From the viewpoint of stable operation, this power supply circuit needs to avoid a temperature rise. Therefore, in order to dissipate heat conducted from the light emitting diode 3 and heat generated by the power supply circuit itself, a slit is made in the housing 22 or heat is dissipated by blowing air. It is preferable that the housing 22 is provided with a fan for causing it to occur.

  The base 23 is located on the upper side of the housing 22, supports the weight of the LED module 1 and the housing 22, and is connected to a commercial 100V power source. The shape of the base 23 is preferably a known E39 type. By making the base 23 E39 type, it can be easily attached to and detached from the socket for a light bulb connected to a commercial 100V power source.

  The connector at the end of the flexible printed wiring board of the LED module 1 is connected to the control circuit and the power supply circuit in the housing 22 through the heat radiation space 21 by electric wiring. Further, the power supply circuit is connected to the base 23 at the upper portion thereof by electric wiring. With these connections, power supplied from the base is supplied to the plurality of light emitting diodes 3 to light them.

  The total output of the light emitting diodes 3 (the total of the LED module outputs of the LED lighting fixtures) is determined from the number of LED lighting fixtures to be installed and the like, and can be set to 60 W or more and 200 W or less, for example. When the total output of the light emitting diode 3 is less than the lower limit, the illuminance of the LED lighting apparatus may be insufficient. On the other hand, when the total output of the light emitting diode 3 exceeds the upper limit, the illuminance of the LED lighting device is increased, but the amount of heat generated by the LED lighting device is increased, and the LED lighting device is increased in size for heat dissipation. May be difficult.

  The luminous flux of the LED lighting fixture is determined from the number of LED lighting fixtures to be installed and the like, and can be, for example, 8000 lm or more and 20000 lm or less. When the luminous flux of the LED lighting fixture is less than the lower limit, the illuminance of the LED lighting fixture may be insufficient. On the other hand, when the luminous flux of the LED lighting fixture exceeds the upper limit, the illuminance of the LED lighting fixture increases, but the amount of heat generated by the LED lighting fixture increases, and the LED lighting fixture becomes larger due to its heat dissipation, making it difficult to handle. There is a risk of becoming.

<Advantages>
Since the LED lighting apparatus includes the LED module 1, the luminous intensity in a specific direction can be increased at low cost, and the illuminance of the entire space can be kept uniform even when the installation density of the LED lighting apparatus is low.

[Other Embodiments]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is not limited to the configuration of the embodiment described above, but is defined by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims. The

  In the above embodiment, the case where the convex portion of the base material of the LED module and the light emitting plate are integrally molded has been described. However, the convex portion and the light emitting plate may not be integrally molded. The structure which affixed the board to the base material using the adhesive agent etc. may be sufficient.

  Further, the convex portion and the light radiating plate may be detachable. Thus, by making the said convex part and a light radiation plate detachable, a light radiation plate can be replaced, for example, the ratio of the scattered light with respect to the whole radiation light of the light radiation plate 4 can be changed easily. Therefore, a suitable light distribution can be easily obtained according to the use conditions.

  The light emitting surface of the light emitting plate may be formed to be replaceable. Since the light emission surface can be changed in this way, the light distribution characteristic of the light emission plate can be easily changed, and a suitable light distribution can be easily obtained according to the use conditions.

  Further, in the above embodiment, the LED module including the light emitting diode on the side surface of one right-sided truncated pyramid is shown. You may have a right-angle frustum. For example, FIGS. 9A and 9B show an LED module 101 having two right-angle frustums. In this LED module 101, a regular decagonal truncated pyramid 2b is stacked in two stages on the upper surface of the regular decagonal truncated pyramid 2a so that the central axes thereof substantially coincide with each other. The light emitting diode 3 is provided on the side surface of the base 2b. Further, the bottom surface of the regular decagonal truncated pyramid 2b is smaller than the top surface of the regular decagonal truncated pyramid 2a, and the LED module 101 extends a certain length from the entire circumference of the bottom surfaces of the regular decagonal truncated pyramid 2a and the regular decagonal truncated pyramid 2b. It has light emitting surfaces 4a and 4b that exit. Even in such a configuration, the light intensity in a specific direction, particularly in a shallow angle direction, can be increased.

  The light emitting surface 4a of the regular twentieth truncated pyramid 2a is not particularly limited as long as the light emitted from the light emitting diode 3 on the side surface of the regular twentieth truncated pyramid 2a can be suitably radiated. For example, the extension length similar to that of the above embodiment is used. It can be the reflectance, the ratio of scattered light, and the like. Similarly, the light emitting surface 4b of the regular decagonal truncated pyramid 2b is not particularly limited as long as the light emitted from the light emitting diode 3 on the side surface of the regular decagonal truncated pyramid 2b can be suitably radiated. Good. Thus, by forming the light emitting surface 4b of the regular decagonal truncated pyramid 2b on the upper surface of the regular decagonal truncated pyramid 2a, part or all of the light emitted from the light emitting diode 3 on the side surface of the regular decagonal truncated pyramid 2a is obtained. It is possible to prevent the light emitting surface 4b of the regular decagonal frustum 2b from being shielded.

  In the said embodiment, although the said LED module was provided with the laminated body of a base material and a flexible printed wiring board, and the light emitting diode was mounted in the flexible printed wiring board, this invention mounted the light emitting diode in the flexible printed wiring board. It is not limited to things. For example, a plurality of rigid printed wiring boards may be laminated on the side surfaces of the convex portions of the metal substrate, and the light emitting diodes may be mounted thereon. In addition, a hollow straight cone may be formed with a printed wiring board on a flat substrate having no projection, or the projection may be formed on the substrate with a resin or the like. A straight wiring body may be formed by arranging a printed wiring board so as to cover the substrate.

  In addition, a right cone or a right truncated cone can be used as the right cone.

  Further, the light emitting surface may be a curved surface. Although the shape of the curved surface is not particularly limited, for example, a curved shape in which the angle formed between the bottom surface of the pyramid (or the truncated pyramid) and the light emitting surface gradually increases from the inner periphery to the outer periphery of the light emitting surface. .

  Furthermore, in the said embodiment, although it was set as the structure which provided a recessed part in the back surface side of a flexible printed wiring board, and was filled with a heat conductive adhesive layer, a recessed part is not an essential component of this invention, but a flexible printed wiring board. You may laminate | stack a normal adhesive bond layer or a heat conductive adhesive bond layer on the whole back surface of a base film.

  Moreover, when providing the said recessed part, you may provide a heat conductive adhesive layer by filling one type of heat conductive adhesive, without dividing a heat conductive adhesive layer into two layers. Further, the base film may be left in a region including the connection edge with the wiring portion in the land portion in plan view. Even if the remaining region is provided in this way, it is possible to suppress a short circuit with the base material due to the drop of the land portion to the back surface side (base material side).

  Furthermore, an LED module that does not leave a base film when a recess is provided as shown in FIG. 6D is also within the intended scope of the present invention. In this LED module, at least the front side portion of the recess 10 is formed in a region covering at least the projection region of the opening of the cover lay 6e and the projection region of the light emitting diode 3 provided at positions corresponding to the plurality of land portions 6c. Yes. Furthermore, a cover lay 6e exists between the plurality of land portions 6c in a plan view substantially perpendicular to the surface of the flexible printed wiring board 6. The upper limit and the lower limit of the opening area of the recess 10 in the base film 6a of the LED module of FIG. 6D can be the same as those of the LED module of FIG. 6A.

  Moreover, like the LED module of FIG. 6E, the flexible printed wiring board 6 may have the through holes 12 in the projection regions of the plurality of land portions 6c. The through-hole 12 is formed in the projection region of the plurality of land portions 6c and penetrates the conductive pattern 6b and the coverlay 6e of the flexible printed wiring board 6. By filling the through hole 12 with the heat conductive adhesive also on the back surface side and the upper part thereof, the heat conductive adhesive abuts on the back surface of the light emitting diode 3 to further promote the heat dissipation effect of the light emitting diode 3. can do. Moreover, it can prevent that a heat conductive adhesive leaks out except the recessed part 10 at the time of thermal conductive adhesive filling.

The lower limit of the average area of the through hole 12 is preferably 0.005 mm ^2, 0.01 mm ² is more preferable. In contrast, the upper limit of the average area of the through-hole 12 is preferably 1 mm ^2, 0.5 mm ² is more preferable. When the average area of the through-holes 12 is less than the above lower limit, the effect of preventing the heat conductive adhesive from leaking and the promotion of the heat dissipation effect may be insufficient. On the contrary, when the average area of the through-hole 12 exceeds the said upper limit, there exists a possibility that the intensity | strength of the flexible printed wiring board 6 may fall.

  The through-hole 12 can be formed before or after forming the recess 10 or simultaneously with the recess 10. As a method for forming the through hole 12, the same method as the method for forming the front side portion of the recess 10 can be used. A plurality of through holes 12 may be formed in one recess 10.

  In the above embodiment, the concave portion is formed so as to include the projected areas of the plurality of land portions to which one light emitting diode is connected. A recess may be formed so as to straddle between a plurality of light emitting diodes so as to include a projected area of one land portion to which the light emitting diodes are connected.

  Furthermore, in each of the above embodiments, the concave portion is formed in a region including the projected areas of a plurality of land portions, but the concave portion may be formed so as to include a projected area of one land portion. In addition, the formation region of the recess may include a region that does not overlap with the projection region of the light emitting diode and the land portion.

  In addition, the said LED lighting fixture can also be applied to lighting fixtures of forms other than the form connected to the socket for light bulbs connected to a commercial 100V power supply.

  Moreover, although the case of the high output LED lighting fixture was demonstrated in the said embodiment, it is also possible to apply to the low output lighting fixture of 60 W or less, for example.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

  In the LED module 101 shown in FIGS. 9A and 9B, an aluminum base 5 and an aluminum regular twentieth pyramid 2a and a regular decagon pyramid 2b were prepared as a right-angle frustum. The inclination angle of the side surfaces of these right-angled frustums with respect to the bottom surface is 69 °. The surface around the convex part of the base material 5 and the upper surface around the regular decagonal truncated pyramid 2b of the regular twentieth truncated pyramid 2a were mirror-polished to form a light emitting surface. It should be noted that the average angle formed by the surface (light emitting surface 4a) around the convex portion of the substrate 5 and the bottom surface of the regular icosahedron frustum 2a and the upper surface around the regular decagonal frustum 2b of the regular icosahedron frustum 2a The average angle formed between the light emitting surface 4b) and the bottom surface of the regular decagonal frustum 2b is 0 °. In addition, the average extension length of the light emitting surface is 15 mm in all cases.

  Next, a flexible printed wiring board having 20 trapezoidal portions that can be along the side surface of the regular decagonal truncated pyramid 2a, and a flexible printed wiring board having 10 trapezoidal portions that can be along the side surface of the regular decagonal truncated pyramid 2b. And prepared. One light emitting diode 3 having no lens at the center was mounted on each trapezoidal portion of the two flexible printed wiring boards. The two flexible printed wiring boards were configured such that a plurality of light emitting diodes 3 mounted on the respective flexible printed wiring boards were connected by a conductive pattern, and the ends of the wirings became connectors. Each of the above-mentioned flexible printed wiring boards has a recess in the area where the light emitting diode 3 is mounted on the back surface, and the recess is filled with a highly thermally conductive resin. Furthermore, the area | region (coverlay surface) other than the light emitting diode 3 of each said flexible printed wiring board was made into white. The two flexible printed wiring boards were respectively disposed on the side surface of the regular decagonal truncated pyramid 2a and the side surface of the regular decagonal truncated pyramid 2b.

  The regular twentieth truncated pyramid 2a and the regular tens truncated pyramid 2b were fixed with overlapping screws. Further, an aluminum heat sink 7 having fins having a sufficient area for heat dissipation was fixed to the back surface of the base material, and a coating having high heat dissipation by radiation was applied to the surface. In this way, an LED module was obtained.

  Using the LED module, an LED lighting apparatus having the same configuration as that of FIG. 8 was assembled. This LED lighting fixture was provided with 30 light-emitting diodes, and was a high-power illumination with a built-in power source with a total light output of 100 W and a luminous flux of 10,000 lm.

  The LED module was connected to a light bulb socket connected to a commercial 100V power supply so that the light-emitting diode 3 faced downward, and the light distribution characteristics were measured.

  From the obtained light distribution characteristics, the strongest luminous intensity was confirmed in the angle direction of 70 ° in absolute value from vertically downward. The light distribution angle was 189 °. Compared to a conventional high-power lighting device (light distribution angle of about 120 °) in which a plurality of light emitting diodes are juxtaposed in a plane, it was confirmed that a much wider range was illuminated brightly.

  Moreover, the LED temperature after lighting for a long time (6 hours or more) is 98 degreeC, it is below a rating (120 degreeC), and it confirmed that the LED lighting fixture had sufficient heat dissipation.

  From the above, it can be seen that when the LED module has a light emitting surface, the light intensity in a specific direction, particularly a shallow angle direction, can be increased, and the illuminance can be kept high in a wide space.

  As described above, the LED module and the LED lighting device of the present invention can increase the luminous intensity in a specific direction at low cost, and can maintain the illuminance uniformly in a wide space even when the installation density of LED lighting fixtures is low.

DESCRIPTION OF SYMBOLS 1,101 LED module 2 Right-angle frustum part 2a Regular dodecagon frustum 2b Regular dodecagon frustum 3 Light emitting diode 3a Solder 4 Light emission board 4a, 4b Light emission surface 5 Base material 5a Through-hole 6 Flexible printed wiring board 6a Base film 6b Conductive pattern 6c Land portion 6d Wiring portion 6e Coverlay 6f Insulating layer 6g Adhesive layer 6h Adhesive layer 7 Heat sink 8 Connector 9 Through hole 10 Recess 11a, 11b Thermally conductive adhesive layer 12 Through hole 21 Heat radiation space 22 Housing 23 Base M Center axis P Remaining area H Opening

Claims (15)

An LED module comprising a plurality of light emitting diodes,
The plurality of light emitting diodes are disposed only on a right cone, a right pyramid, a right frustum or a right frustum side surface,
The right cone, straight pyramid, out a predetermined length extending from the entire periphery of the frustoconical or straight truncated pyramidal bottom, have a light emitting surface which reflects or scatters at least part of the light emitted from the light emitting diode,
The plurality of light emitting diodes are mounted on a flexible printed wiring board,
The flexible printed wiring board is laminated on the surface of the base film, a conductive pattern that is laminated on the surface side of the base film, and includes one or a plurality of land portions and a wiring portion that is connected to the land portion. And a coverlay having an opening formed at a position corresponding to the one or more land portions,
Of the back surface of the flexible printed wiring board, having a recess reaching the back surface of the conductive pattern in at least a part of the projection region of one or more land portions where the light emitting diode is mounted,
It further comprises a heat conductive adhesive filling the recess,
The LED module in which the said heat conductive adhesive contains the 1st heat conductive adhesive layer with which the surface side of the said recessed part is filled, and the 2nd heat conductive adhesive layer with which the back side of the said recessed part is filled .   The LED module according to claim 1, wherein an average angle formed by the bottom surface and the light emitting surface is 0 ° or more and less than 30 °. On the plane including the central axis of the right cone, right pyramid, right frustum or right frustum, the average from the bottom surface side formed by the straight line connecting the center of the light emitting diode and the end of the light emitting surface and the central axis The LED module according to claim 1 or 2, wherein the angle is not less than 45 ° and not more than 120 °.   4. The LED module according to claim 1, wherein the average extension length of the light emitting surface is 3 mm or more and 150 mm or less.   The LED module according to any one of claims 1 to 4, wherein a reflectance of the light emitting surface is 50% or more.   The LED module according to any one of claims 1 to 5, wherein a ratio of scattered light to the entire emitted light on the light emitting surface is 0% or more and 50% or less. A right cone, right pyramid, right frustoconical or right frustum-shaped convex portion disposed in the central portion, and a light emitting plate disposed around the convex portion, the surface of which forms the light emitting surface. Further comprising a substrate having
The LED module according to any one of claims 1 to 6, wherein the flexible printed wiring board is disposed at least on a surface of a convex portion of the base material.   The LED module according to claim 7, wherein the convex portion and the light emitting plate are integrally formed.   The LED module according to claim 7, wherein the convex portion and the light emitting plate are detachably formed. The LED module according to any one of claims 7 to 9 , wherein the light emitting plate is made of metal. The LED module according to any one of claims 1 to 10 , wherein an inclination angle of the side surface with respect to the bottom surface is 55 ° or more and 82 ° or less. The direction in which the luminous intensity is maximum in the range of −90 ° to 90 ° from the reference direction to the left and right with respect to the origin and the center axis apex direction as the reference, with the base of the right cone, right cone, right cone frustum or right cone frustum as the origin. The LED module according to any one of claims 1 to 11 , wherein an absolute value of an angle formed from the reference direction is 40 ° or more and 80 ° or less. The LED module according to claim 12 , wherein a ratio of the maximum value of the luminous intensity in the range to the luminous intensity in the reference direction is 1 or more and 3 or less. An LED lighting apparatus comprising the LED module according to any one of claims 1 to 13 . The LED lighting apparatus according to claim 14, which is used as a light bulb.

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