JP2013065574A - Lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lighting device capable of irradiating in a wide light distribution angle.SOLUTION: The lighting device 10 is provided with an LED module 14, a holding member 22 which protrudes a mounting part on which the LED module 14 is mounted in a light emission direction of the LED module 14 and holds the LED module 14, and a light distribution lens 12 which makes incident the emission light from the LED module 14 and emits the incident light to a light emission direction side of the LED module 14 and an opposite side to the light emission direction.

Description

  The present invention relates to an illumination device that can illuminate with a wide light distribution angle.

  Semiconductor light emitting devices such as light emitting diodes (LEDs) directly convert electrical energy into light energy. For this reason, compared with incandescent bulbs such as halogen lamps and fluorescent lamps, it is characterized by high efficiency and low calorific value during light emission. An incandescent bulb is one that converts electrical energy into thermal energy once and uses radiation associated with the heat generation, and its conversion efficiency is low in principle. In a fluorescent lamp, electric energy is converted into discharge energy, and the conversion efficiency is low as well. On the other hand, LEDs have high conversion efficiency, have a long life that can be considered semi-permanent, and do not have the problem of flickering like the light of fluorescent lamps.

  As described above, the LED has advantages such as long life and low power consumption. In recent years, attention has been paid to the advantages of such LEDs, and lighting devices have been developed that use LEDs as light sources instead of incandescent bulbs and fluorescent lamps.

  For example, Patent Document 1 discloses an LED that obtains substantially uniform brightness by attaching a diffusion sheet to the outer surface of a light-transmitting globe that covers the LED and diffusing light incident on the globe from the LED through the diffusion sheet. A light bulb is disclosed.

  In this LED bulb, the light emitted from each of the LEDs is diffused by the diffusion sheet attached to the globe as described above. By this diffusion, each diffusion position on the globe functions as a new light emitting point. Thereby, a substantially uniform luminance is obtained over substantially the entire area of the globe, and it is possible to make it difficult for a person to be dazzled or uncomfortable.

JP 2008-91140 A (published April 17, 2008)

  By the way, although LEDs have the advantages as described above, so far, the application of LEDs has been limited to a very limited range such as control panels of various devices and display devices such as electric bulletin boards, and used for lighting devices. There were few examples. This is because although the luminance of the LED is extremely high, the light emission area from one LED is very small, and sufficient light distribution characteristics as a lighting fixture cannot be obtained.

  For this reason, an illuminating device using an LED as a light source is strongly and strongly desired to improve light distribution characteristics, that is, to realize illumination with a wide light distribution angle, such as an incandescent bulb and a fluorescent lamp.

  However, in the illumination device described in Patent Document 1, although it is possible to cause the entire globe to emit light with substantially uniform brightness by the diffusion sheet, the substrate on which the LED is mounted is a base that faces the opening on the globe base side Is attached. With this attachment, all the light from the LED, which is a highly directional light source, is emitted in the direction opposite to the base, and only a part of the light diffused by the diffusion sheet is emitted to the base side. It becomes. For this reason, in the said conventional illuminating device, the light radiated | emitted to the nozzle | cap | die side is few, and obtains wide light distribution which radiates | emits illumination light enough to the back of the illuminating device on the opposite side to the light emission direction of LED I can't.

  In view of the above problems, an object of the present invention is to provide an illuminating device that emits illumination light to the side opposite to the light emitting direction of a light emitting element and can illuminate with a wide light distribution angle.

  In order to achieve the above object, an illumination device according to the present invention includes an LED module having an LED, a holding member having a mounting portion for mounting the LED module, and a light emitting direction of the LED. And an optical member that emits the incident light in the light emitting direction, the peripheral edge direction of the holding member, and the light emitting direction, and the LED module, the holding member, and the optical. A cover member arranged to cover the member and transmitting the light emitted from the LED, and the optical member has a recess in the center of the surface on the light emitting direction side, and the mounting By projecting the part in the light emitting direction of the LED, the light emitted from the optical member to the side opposite to the light emitting direction passes outside the peripheral part of the holding member. Characterized in that there. In addition, it has a cylindrical heat radiating part for radiating heat from the LED module, and the mounting part protrudes in the light emitting direction of the LED from the outer edge part of the upper end of the heat radiating part. .

  According to said structure, the light radiate | emitted from a light emitting element injects into the bottom face of an optical member as it is. The light emitting element is, for example, an LED, the light distribution angle of the light emitting surface is narrow, and the light emitting element travels almost straight to the bottom surface of the optical member along the light emitting direction. The light incident on the bottom surface of the optical member travels inside the optical member and reaches the ceiling surface facing the bottom surface.

  The bottom surface and the ceiling surface of the optical member transmit or reflect light, and transmit or reflect light depending on the incident angle of light incident on each of the optical members. The optical member emits light to the light emitting direction side of the light emitting element and to the side opposite to the light emitting direction by such transmission and reflection of light.

  Here, the “opposite direction to the light emission direction” means not only the direction opposite to the light emission direction but also light emission from the opposite direction as long as light distribution to the rear of the illumination device can be obtained. It is meant to include the direction shifted to the direction side. That is, the “opposite side to the light emitting direction” includes all the directions toward the range that can be regarded as the rear side of the illumination device when viewed from the optical member.

  The optical member distributes light in a direction different from the light emitting direction of the light emitted from the light emitting element by emitting the light incident from the light emitting element to the side opposite to the light emitting direction.

  On the other hand, the light emitting element is mounted on the mounting portion of the holding member that protrudes in the light emitting direction of the light emitting element.

  Here, “projecting in the light emitting direction of the light emitting element” means projecting from the peripheral edge of the holding member. For example, when the holding member is divided into a convex portion and a peripheral portion surrounding the convex portion, the top surface of the convex portion is the mounting portion. A light emitting element is mounted on the mounting portion, and the convex portion protrudes from the peripheral edge portion in the light emitting direction of the light emitting element. In this case, it can be said that the mounting part protrudes in the light emitting direction of the light emitting element with respect to the peripheral part.

  For this reason, in the light emitted from the light emitting element and distributed by the optical member, the ratio of the light directed to the side opposite to the light emitting direction of the light emitting element can be reduced, and the holding member can be reduced. The ratio of the light emitted to the outside of the lighting device without being blocked can be increased.

  Therefore, according to said structure, the light radiate | emitted from light emitting elements, such as LED, can distribute light efficiently behind an illuminating device, and the illuminating device which can be illuminated with a wide light distribution angle is realizable.

  The optical member preferably emits the incident light toward the peripheral edge of the holding member.

  According to said structure, the light radiate | emitted from the optical member can be made to go to the peripheral part of a holding member. Therefore, it is possible to realize an illuminating device capable of efficiently distributing light emitted from the light emitting element to the rear of the illuminating device and illuminating with a wide light distribution angle.

  The light emitting element, the holding member, and the optical member are disposed so as to cover and further include a cover member that transmits light emitted from the light emitting element, and the light emitting direction of the light emitting element of the cover member However, it is preferable that the maximum value of the diameter in the vertical direction is larger than the diameter of the peripheral edge of the holding member.

  In the above configuration, the cover member has a plane perpendicular to the light emitting direction of the light emitting element and includes a plane including the maximum diameter as a boundary, and the upper half that is a portion on the light emitting direction side of the light emitting element, and the light of the light emitting element It can be divided into a lower half which is a part opposite to the emission direction side. The lower half is a portion on the holding member side, and the diameter of the peripheral portion of the holding member is included in the range of the diameter.

  Here, if the maximum diameter is larger than the diameter of the peripheral portion of the holding member, the lower half of the cover member can be wound around the lower side of the upper half, in other words, the side opposite to the emission direction side of the light emitting element. .

  Therefore, according to the above configuration, the light diffused in the lower half of the cover member is illuminated to the side opposite to the light emitting direction of the light emitting element, and a wide light distribution is obtained.

  The cover member is provided in parallel with a first curved surface provided on the light emitting element side, and on a side opposite to the light emitting direction side of the light emitting element with respect to the first curved surface, and has a smaller curvature than the first curved surface. And a second curved surface defined by a radius.

  In the above configuration, the cover member is divided into a first curved surface provided on the light emitting element side and a second curved surface provided in parallel to the light emitting direction side of the light emitting element with respect to the first curved surface. can do.

  Here, the second curved surface is defined by a smaller radius of curvature than the first curved surface, so that the second curved surface is below the first curved surface, in other words, on the side opposite to the emission direction side of the light emitting element. , You can wrap around.

  Therefore, according to the above configuration, the light diffused in the lower half of the cover member is illuminated to the side opposite to the light emitting direction of the light emitting element, and a wide light distribution is obtained.

  The holding member is preferably provided with a reflecting member that reflects light from the light emitting element reflected by the cover member.

  According to the above configuration, the reflected light is reflected again by the reflecting member without passing through the cover member and travels toward the cover member. Therefore, the light distributed by the optical member can be further directed to various angles, and an illuminating device capable of illuminating with a wider light distribution angle can be realized.

  The illuminating device according to the present invention has a cylindrical heat radiating portion that radiates heat from the light emitting element, and the mounting portion protrudes in a light emitting direction of the light emitting element from an outer edge portion of an upper end of the heat radiating portion. It is characterized by. Moreover, it is preferable that the said light emitting element is LED.

  According to the above configuration, it is possible to realize a lighting device with a long life and low power consumption.

  According to the present invention, it is possible to provide an illuminating device that can distribute light emitted from a light emitting element to the side opposite to the light emitting direction of the light emitting element and can illuminate with a wide light distribution angle.

It is sectional drawing which shows schematic structure of the illuminating device which concerns on one Embodiment of this invention. It is an external view of the said illuminating device. It is a disassembled perspective view of the said illuminating device. It is sectional drawing of the light distribution lens of the said illuminating device. It is a bird's-eye view of a light distribution lens. It is a schematic diagram which shows the arrangement configuration of a globe cover, a light distribution lens, an LED module, a heat dissipation sheet member, and a holding member. It is sectional drawing of the 1st modification of the said light distribution lens. It is a bird's-eye view of the 1st modification of the above-mentioned light distribution lens. It is sectional drawing of the 2nd modification of the said light distribution lens. It is a bird's-eye view of the 2nd modification of the above-mentioned light distribution lens. It is sectional drawing of the 1st modification of the said holding member. It is a bird's-eye view of the 1st modification of the above-mentioned holding member. It is sectional drawing of the 2nd modification of the said holding member. It is a bird's-eye view of the 2nd modification of the above-mentioned holding member. It is sectional drawing of the 3rd modification of the said light distribution lens. It is a bird's-eye view of the 3rd modification of the above-mentioned light distribution lens. It is a figure for demonstrating the effect of the said glove cover, (a) respond | corresponds to the comparative example of the said glove cover, (b) respond | corresponds to the said glove cover.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a schematic configuration of a lighting apparatus according to an embodiment of the present invention, and FIG. 2 is an external view of the lighting apparatus shown in FIG. FIG. 3 is an exploded perspective view showing a schematic configuration of the illumination device shown in FIG.

(Lighting device 10)
As shown in FIG. 2, the lighting device 10 according to an embodiment of the present invention includes a light emitting unit 1, a support unit 2, an insulating ring 3, and a base 4. Specifically, as shown in FIGS. 1 and 3, the lighting device 10 includes a light emitting unit 1, a support unit 2, an insulating ring 3, and a base 4 connected in this order. Hereinafter, for the sake of convenience, the light emitting unit 1 side may be referred to as the front side of the lighting device 10 and the base 4 side may be referred to as the rear side of the lighting device 10.

(Light Emitting Unit 1)
First, the light emitting unit 1 includes a globe cover (cover member) 11, a light distribution lens (optical member) 12, a reflection member 13, an LED module 14, and a heat dissipation sheet member 15.

(Glove cover 11)
The globe cover 11 has a curved surface shape such as a hemispherical shape or a dome shape. The globe cover 11 has the light distribution lens 12, the reflection member 13, the LED module 14, and the heat radiating sheet member 15 disposed therein, and is attached to the support portion 2 while covering them.

  The globe cover 11 protects one or a plurality of LEDs mounted on the LED module 14 from external pressure and external force.

  Furthermore, the globe cover 11 transmits light emitted from the LEDs of the LED module 14 and diffuses or scatters part of the light. The globe cover 11 reflects a part of the light emitted from the LED again toward the inside thereof. For example, glass or a synthetic resin can be used for the globe cover 11. Then, as described above, for example, a diffusion material mainly composed of calcium is applied to the inner surface which is the inner surface of the globe cover 11 so that the light emitted from the LED is transmitted, diffused, scattered, and reflected. Just keep it. By adjusting the coating amount, the light transmittance and the degree of diffusion of the globe cover 11 can be optimized.

  Of course, the lighting device 10 does not achieve light distribution with a wide light distribution angle to the rear of the lighting device 10 by using such diffusion of light by the globe cover 11. Certainly, the greater the amount of diffusing material applied, the greater the amount of light that diffuses and scatters, and the more light that is emitted to the rear of the illumination device 10. However, conversely, the amount of light that is emitted from the LED module 14 is reflected by the globe cover 11 and returns to the inside of the globe cover 11 again. That is, in the globe cover 11 having a large amount of diffusing material, the emitted light from the LED module 14 repeats many internal reflections, and the light returning to the inside of the globe cover 11 is absorbed by the LED module 14 and the reflecting member 13. The transmittance of the cover 11 is reduced. This leads to a decrease in the luminous flux emitted from the illumination device 10.

  Therefore, as will be described later, the illuminating device 10 includes a structure for increasing the light distribution to the rear of the illuminating device 10 (hereinafter sometimes referred to as “rear light distribution structure”), so that The reduction of the luminous flux due to the decrease in the transmittance is minimized, the light distribution to the rear of the illumination device 10 is increased, and illumination with a wide light distribution angle is realized.

  The LED module 14 generates a relatively large amount of heat when the LED is turned on. For this reason, the globe cover 11 is preferably made of a heat resistant material. Such a heat resistant material is, for example, milky white polycarbonate resin. This polycarbonate resin is excellent in impact resistance, heat resistance, and light diffusibility, and is suitable for use in the glove cover 11.

(Light distribution lens 12)
The light distribution lens 12 is attached to the reflection member 13 while covering the LED module 14. As shown in FIG. 1, the light distribution lens 12 is arranged in the emission direction of the light emitted from the LED of the LED module 14, and the light emitted from the LED of the LED module 14 is incident as it is.

  The light distribution lens 12 is made of a transparent solid with respect to the wavelength of light emitted from the LED of the LED module 14, and has a lens function required for the illumination device 10 to have a rear light distribution structure described later. With this lens function, the light distribution lens 12 changes the traveling direction of the light emitted from the LED of the LED module 14 not only in front of the illumination device 10 but also behind it, that is, the light emitted from the LED from the LED module 14. Can also be directed to the opposite side of the emission direction.

  The light distribution lens 12 is disposed in the vicinity of the LED module 14. The light emitted from the LED of the LED module 14 enters the light distribution lens 12 with little progress in the air that is the outside air. That is, the optical path from the LED module 14 to the light distribution lens 12 is short, and the decrease of the light flux in the optical path is suppressed. With such an arrangement, a large amount of light from the LED module 14 is incident on the light distribution lens 12, and as a result, the traveling direction of the large amount of light is opposite to the light emitting direction of the LED module 14. The lighting device 10 can be directed rearward.

(Reflection member 13)
The reflecting member 13 is for making the traveling direction of the light diffused, scattered and reflected by the globe cover 11 out of the light emitted from the LEDs of the LED module 14 again toward the globe cover 11 side. By such reflection of light by the reflecting member 13, the amount of light distributed to the rear of the illumination device 10 can be increased.

  The reflecting member 13 can be made of a resin material having a high reflectance. Such a resin material is usually inexpensive, and the reflecting member 13 can be manufactured at low cost.

  The reflecting member 13 is formed by grinding a metal such as Al, brass, stainless steel or the like into a shape shown in FIGS. 1 and 3 using a lathe / milling machine or the like by a press machine or the like. It may be polished and formed. Furthermore, it is preferable to apply nickel (Ni) plating or gold (Au) plating to these surfaces because the reflectance is improved. As an inexpensive and simple method, a structure in which a metal thin film having a high reflectance such as an Al thin film is bonded may be used. Alternatively, a structure in which a thermoplastic resin is processed into the shape shown in FIGS. 1 and 3 by extrusion molding or injection molding, and a highly thin metal thin film or dielectric multilayer film such as an Al foil is deposited on this surface by vacuum evaporation or sputtering. Alternatively, a structure in which a highly reflective polyester white film or the like is adhered may be used.

(LED module 14)
The LED module 14 (light emitting element) includes a plurality of LEDs and a ceramic substrate on which the plurality of LEDs are mounted. As the LED mounted on the LED module 14, LEDs of various colors (wavelengths) can be used. However, for illumination purposes, white LEDs are preferred because they are natural to the human eye.

  As white LED, the thing of various structures can be used. For example, a type in which a fluorescent material that emits fluorescence is excited by an LED such as blue light or ultraviolet light can be used. Further, the three LEDs of red (R), green (G), and blue (B) may be arranged adjacent to each other so as to be regarded as a point light source. Alternatively, three LEDs of red, green, and blue may be stacked vertically and arranged.

(Heat dissipation sheet member 15)
The heat radiating sheet member 15 conducts heat generated from the LEDs of the LED module 14 to the heat radiating member 23. As the heat dissipating sheet member 15, for example, a product name “Sarcon” (thermal conductivity 6.0 W / m · K) manufactured by Fuji Polymer Industries Co., Ltd. can be used.

(Supporting part 2)
The support portion 2 is a main body portion of the lighting device 10 and includes a decorative ring 21, a holding member 22, a heat radiating member 23, a power supply module 25, and a holder 26.

(Decorative ring 21)
The decorative ring 21 is an annular member that partitions the light emitting unit 1 and the support unit 2. For example, a resin material can be used for the decorative ring 21, and the user can look at the lighting device 10 by devising the shape, pattern, color, and the like.

  In addition, the decorative ring 21 may be made of a highly heat conductive material such as metal instead of the resin. In this case, the heat generated from the LEDs of the LED module 14 can be radiated to the outside or conducted to the heat radiating member 23.

  A holding member 22 is fixed to the upper surface of the decorative ring 21 by screws 24. Further, a flange is formed on the outer edge portion of the upper surface of the decorative ring 21, and the glove cover 11 is attached.

(Holding member 22)
The holding member 22 is for arranging and holding the LED module 14. Specifically, in the holding member 22, the LED module 14 is disposed on the LED holding surface that is the surface on the globe cover 11 side so as to sandwich the heat dissipation sheet member 15, and the light distribution lens 12 is disposed so as to sandwich the reflecting member 13. Has been placed.

  Specifically, the holding member 22 has a convex part described later on the LED holding surface, which is required for the lighting device 10 to have a rear light distribution structure described later. That is, the holding member 22 includes a convex portion that protrudes toward the globe cover 11 side. This convex portion places and holds the LED module 14 on the top surface. The top surface of the convex portion is preferably a single flat surface, for example, so that the LED module 14 can be stably held. This top surface is a place where the LED module 14 is mounted, and therefore can be said to be a mounting portion of the LED module 14.

  Since the holding member 22 has such a convex portion, the light directed toward the rear of the illumination device 10 by the light distribution lens 12 can be efficiently emitted to the outside of the light emitting unit 1.

As a material of the holding member 22, for example, sapphire (Al ₂ O ₃ ), magnesia (MgO), gallium nitride (GaN), spinel (MgAl ₂ O ₄ ), iron (Fe), or the like can be used. If it is such a material, the heat_generation | fever from LED of the LED module 14 can be escaped efficiently.

  The holding member 22 may be a plate-like member that is not bent except for the above-described convex portion, or may have a bent portion or a curved portion.

  The thickness of the holding member 22 is preferably 1.0 mm or more and 3.0 mm or less. If the thickness is less than 1.0 mm, the LED module 14 may not be sufficiently durable to be held, and the LED module 14 may not be held for a long time. On the other hand, if the thickness exceeds 3.0 mm, the weight increases, which may lead to an increase in cost.

(Heat dissipation member 23)
The heat radiating member 23 is a cylindrical hollow member, and accommodates the holder 26 holding the power supply module 25 therein. The heat radiating member 23 radiates heat from heat sources such as the LED module 14 and the power supply module 25. For example, the heat radiating member 23 radiates heat generated in the support portion 2 to the outside. An O-ring (not shown) is provided on the outer edge of the upper surface of the heat dissipation member 23. As a result, the decorative ring 21 is fitted in close contact with the upper surface of the heat radiating member 23. On the other hand, the insulating ring 3 is attached to the lower end portion of the heat dissipation member 23.

  In addition, since all the heat radiating members 23 aim at heat radiation, it is preferable to comprise from the metal with favorable heat conductivity. For example, the heat dissipation member 23 is preferably made of a metal such as aluminum (Al), copper (Cu), iron (Fe), nickel (Ni), or an alloy thereof. The heat dissipating member 23 may be made of an industrial material such as aluminum nitride (AlN) or silicone carbide (SiC), or may be made of a synthetic resin such as a high thermal conductive resin.

(Power supply module 25)
The power supply module 25 is a power supply circuit unit that supplies power to the LEDs of the LED module 14. The power supply module 25 is also a control circuit unit that controls the lighting state (light emission color, light emission amount, etc.) of the LED of the LED module 14. The power supply module 25 is mounted in the holder 26 and accommodated in the heat dissipation member 23. The power module 25 includes a power circuit board and a plurality of electronic components mounted on both surfaces of the power circuit board.

  The power circuit board is a printed board having wiring. The electronic component is a circuit component that controls lighting of the LED of the LED module 14. The power circuit board is preferably made of a metal having good thermal conductivity such as aluminum in order to enhance heat dissipation. Further, the power circuit board may be made of a nonmetallic member such as a glass epoxy material or may be made of ceramics.

  The electronic component is, for example, a circuit component for LED lighting control, dimming, or toning. Specifically, the electronic component is an electrolytic capacitor, a ceramic capacitor, a current transformer, a film capacitor, a REC (rectifier element, diode bridge), a resistor, a transistor, a switching element, or the like.

(Holder 26)
The holder 26 holds the power supply module 25 inside. That is, the holder 26 is a PCB holder. An opening is formed in the side surface of the holder 26, and the power supply module 25 is disposed with the electronic component facing the opening. Thereby, the heat generated in the electronic component is efficiently conducted to the heat radiating member 23 through the opening. One end of the holder 26 is fixed to the decorative ring 21, and the other end of the holder 26 is fixed to the insulating ring 3. The holder 26 is covered with the heat radiating member 23. The holder 26 is preferably made of a material having electrical insulation and thermal conductivity. For example, the holder 26 can be formed from PBT (polybutylene terephthalate), acrylic resin, ABS resin, polyamide resin, or the like.

  The internal space formed by the support portion 2 and the insulating ring 3 may be filled with a potting resin portion. Thereby, the power supply module 25 is electrically insulated and fixed in the heat dissipation member 23. The potting resin part conducts heat from the power supply module 25 generated in the support part 2 and heat from the LED module 14 to the heat radiating member 23. For this reason, it is preferable that the potting resin part is formed from resin with high heat conductivity. For example, the potting resin portion can be formed from a synthetic resin such as a heat-resistant silicone resin, an epoxy resin, or a urethane resin having good thermal conductivity and electrical insulation.

(Insulation ring 3)
The insulating ring 3 is made of an electrically insulating material. The upper end portion of the insulating ring 3 is attached to the lower end portion of the heat dissipation member 23. The insulating ring 3 has a thread formed on the outer surface, and is screwed into the base 4 to be connected.

(Base 4)
The base 4 is a metal fitting for external connection, for example, a general E26 type metal fitting. That is, the base 4 supplies power from an external power supply (not shown) to the power supply module 25. On the inner surface of the base 4, a thread that engages with a thread formed on the outer surface of the insulating ring 3 is formed. Thereby, the insulating ring 3 is screwed and connected. That is, the screw thread formed on the inner surface of the base 4 is a screwing mechanism for screwing the base 4 to the insulating ring 3 and connecting it.

  A screw thread is also formed on the outer surface of the base 4. Thereby, the illuminating device 10 can be attached by being screwed into a socket provided on the ceiling or the like.

(Backward light distribution structure)
Next, the rear light distribution structure included in the illumination device 10, which is a characteristic part of the present invention, will be described with reference to FIGS. 4, 5, and 6. 4 is a cross-sectional view of the light distribution lens 12, FIG. 5 is a bird's eye view of the light distribution lens 12, and FIG. 6 is a globe cover 11, the light distribution lens 12, the LED module 14, the heat radiation sheet member 15, and the holding member 22. It is a schematic diagram which shows the arrangement configuration. Note that FIG. 6 is a schematic one, and it should be noted that the ratio of dimensions of each part is different from the actual one.

  In this rear light distribution structure, as shown in FIG. 6, the light emitted from the LED of the LED module 14 is directly the light incident surface (bottom surface) of the light distribution lens 12 that faces the LED module 14. It enters into 121. The light incident on the light incident surface 121 travels as it is inside the light distribution lens 12 and travels toward the light distribution surface (ceiling surface) 122 of the light distribution lens 12. The light distribution surface 122 is a surface facing the light incident surface 121, and distributes light incident from the light incident surface 121.

  In the light distribution surface 122, for example, the light traveling by the arrow indicated by A in FIG. 6 enters the light distribution lens 12 from the light incident surface 121, and passes through the light distribution surface 122 while maintaining the traveling direction. . That is, the light traveling by the arrow indicated by A is emitted from the light distribution lens 12 along the emission direction of the light emitted from the LED of the LED module 14.

  Further, the light traveling by the arrow indicated by B in the drawing enters the light distribution lens 12 from the light incident surface 121 and reaches the light distribution surface 122 as it is along the emission direction. The light traveling by the arrow indicated by B is reflected without passing through the light distribution surface 122. In addition, it goes without saying that light traveling by the arrow indicated by B ′ in the drawing, that is, light that reaches the light distribution surface 122 and does not reflect on the light distribution surface 122 and also transmits there is also present.

  Similarly, the light traveling by the arrow indicated by C in the figure enters the light distribution lens 12 from the light incident surface 121 and reaches the light distribution surface 122 as it is along the light emission direction. The light traveling by the arrow indicated by C is reflected without passing through the light distribution surface 122. Here, there is also light that travels by an arrow indicated by C ′ in the drawing, that is, light that reaches the light distribution surface 122 and is transmitted without being reflected by the light distribution surface 122.

  In short, the light distribution surface 122 does not function as a total reflection surface, but has a function of reflecting, refracting, or transmitting light emitted from the LED of the LED module 14.

  Here, as described above, the holding member 22 has the convex portion 31, and the LED module 144 is disposed on the top surface (in other words, the mounting portion) 32 of the convex portion 31. For this reason, the light traveling by the arrows indicated by B and C is emitted outside the light emitting unit 1 without being blocked by the holding member 22.

  That is, if the holding member 22 does not have such a convex portion 31 and is a member having a simple flat plate shape, the light traveling by the arrows indicated by B and C is blocked by the holding member 22. It will be. For this reason, even if the light distribution lens 12 can distribute the light to the rear of the illumination device 10, it is difficult to emit the light to the outside of the light emitting unit 1.

  Thus, according to the rear light distribution structure of the lighting device 10, the LED module 14 is disposed on the top surface of the convex portion 31 of the holding member 22, so that the light distribution lens 12 causes the rear of the lighting device 10. The distributed light can be efficiently emitted to the outside of the light emitting unit 1.

  In other words, according to this rear light distribution structure, the light traveling along the light emission direction of the LED of the LED module 14, that is, the light traveling toward the front of the lighting device 10 is directed toward the rear of the lighting device 10. It is possible to effectively use the light distribution lens 12 having a lens function that can be used.

  Here, the height of the convex portion 31, in other words, the protruding amount of the convex portion 31 from the holding member 22 should be determined from the degree of the lens function of the light distribution lens 12. In other words, the height (projection amount) may be such that the light directed toward the rear of the illumination device 10 by the lens function of the light distribution lens 12 is emitted to the outside of the light emitting unit 1 without being blocked by the holding member 22. . That is, it is only necessary that the light traveling from the light distribution lens 12 toward the rear of the illumination device 10 can pass outside the peripheral portion 33 of the holding member 22.

  By doing so, it becomes unnecessary to make the convex part 31 higher than necessary, and the arrangement of the LED module 14 can be stabilized.

  Moreover, the light distribution lens 12 and the globe cover 11 do not approach more than necessary. The light distribution surface 122 of the light distribution lens 12 can be regarded as a light emitting point when viewed from the outside of the illumination device 10. This is because light is distributed from the light distribution surface 122 in various directions. For this reason, that the light distribution lens 12 approaches the globe cover 11 means that the light emitting point approaches the globe cover 11. In general, when the light emitting point approaches the globe cover 11, a striped pattern is projected on the globe cover 11, which is very annoying for users who view the illumination device 10 from a distance.

  In the rear light distribution structure of the illuminating device 10, a convex portion 31 that is a stepped portion or an inclined portion in the holding member 22 is provided. By providing the convex portion 31, the peripheral portion of the holding member 22 is arranged with respect to the light distribution lens 12 while maintaining the distance between the globe cover 11 and the light distribution lens 12 so that the stripe pattern does not occur. It can be located on the base side. For this reason, it is possible to spread light distribution to the rear of the illumination device 10 without bringing the globe cover 11 and the light distribution lens 12 closer than necessary. Therefore, the striped pattern is not projected.

  That is, according to the illuminating device 10, as shown in FIG. 6, the light distribution lens 12 positions the light distribution surface 122 as a light emitting point closer to the light emission direction side of the LED than the mounting portion 32. Light is emitted from the light distribution surface 122 in the direction opposite to the light emission direction of the LED. For this reason, it is possible to increase the proportion of light emitted to the base 4 side outside the peripheral edge portion 33 of the holding member 22, and to obtain a wide light distribution that emits light to the rear of the illumination device 10. is there.

  Further, the mounting portion 32 protrudes toward the light emission direction side with respect to the peripheral edge portion 33 of the holding member 22, so that the position of the light distribution surface 122 is further set to the light emission direction side, that is, the peripheral edge portion 33 of the holding member 22. Therefore, it is possible to reduce the ratio of the light shielded inside the holding member 22.

  Furthermore, in the illuminating device 10, the mounting portion 32 protrudes from the peripheral edge portion 33 of the holding member 22 in order to position the light distribution surface 122 as a light emitting point more on the light emitting direction side. For this reason, the transmission distance of the light transmitted through the light distribution lens 12 can be shortened without increasing the height of the light distribution lens 12 in the light emitting direction. Therefore, it is possible to reduce the attenuation of the light flux due to transmission through the light distribution lens 12, and the light utilization efficiency can be further improved.

  In addition, the following effects can also be acquired by the back light distribution structure of the illuminating device 10. FIG.

  In any case, the light transmitted and reflected by the light distribution surface 122 of the light distribution lens 12 travels toward the globe cover 11 and reaches the globe cover 11. For example, as shown in FIG. 6, the light traveling by the arrow indicated by D in the figure passes through the globe cover 11 and is emitted to the outside of the light emitting unit 1.

  Further, the light traveling by the arrow indicated by E in the figure is diffused when passing through the globe cover 11 and its traveling direction is changed. Of course, improvement in the light distribution characteristics of the illumination device 10 is also expected by this change in the traveling direction.

  On the other hand, the light traveling by the arrow indicated by F in the figure is reflected without passing through the globe cover 11. In this case, the light travels toward the inside of the globe cover 11 again. As described above, the reflecting member 13 is disposed on the LED holding surface of the holding member 22. The light reflected by the globe cover 11 and traveling again toward the inside of the globe cover 11 is further reflected again by the reflecting member 13 and goes toward the globe cover 11, for example.

  By repeating such reflection, the light distributed by the light distribution lens 12 is further directed to various angles, which contributes to the improvement of the light distribution characteristics of the lighting device 10.

  Further, the globe cover 11 preferably has a maximum value of a diameter perpendicular to the light emitting direction of the LED module 14 larger than the diameter of the peripheral edge portion 33 of the holding member 22. In this case, the globe cover 11 has a plane that includes a maximum diameter in a direction perpendicular to the light emission direction of the LED module 14 as a boundary, and an upper half that is a portion on the light emission direction side of the LED module 14 and the LED module 14. It can be divided into a lower half which is a portion on the opposite side to the light emitting direction side. The lower half is a portion on the holding member 22 side, and the diameter of the peripheral edge portion 33 of the holding member 22 is included in the range of the diameter.

  If the maximum diameter of the globe cover 11 is larger than the diameter of the peripheral portion 33 of the holding member 22, the lower half of the globe cover 11 wraps around the lower side of the upper half, in other words, the side opposite to the emission direction side of the light emitting element. Can be made.

  Therefore, the light diffused in the lower half of the globe cover 11 is illuminated to the side opposite to the light emitting direction of the LED module 14, and a wider light distribution is obtained.

(Modification of light distribution lens 12)
7 is a cross-sectional view of a light distribution lens 12a which is a first modification of the light distribution lens 12, and FIG. 8 is a bird's-eye view of the light distribution lens 12a of FIG. The light distribution lens 12 a has a light incident surface 121 a corresponding to the light incident surface 121 of the light distribution lens 12 and a light emitting surface 122 a corresponding to the light distribution surface 122 of the light distribution lens 12.

  The difference between the light distribution lens 12a and the light distribution lens 12 is that both the light incident surface 121a and the light exit surface 122a are incident depending on whether or not the incident angle of the light with respect to each exceeds a specific angle. It is in the point of transmitting or reflecting light.

  That is, the light distribution lens 12a realizes a lens function equivalent to that of the light distribution lens 12 by a combination of the light incident surface 121a and the light emitting surface 122a.

  Similarly, FIG. 9 is a cross-sectional view of a light distribution lens 12b that is a second modification of the light distribution lens 12, and FIG. 10 is a bird's-eye view of the light distribution lens 12a of FIG. The light distribution lens 12 b includes a light incident surface 121 b corresponding to the light incident surface 121 of the light distribution lens 12 and a light emitting surface 122 b corresponding to the light light distribution surface 122 of the light distribution lens 12.

  Similarly to the light distribution lens 12a, the light distribution lens 12b realizes a lens function equivalent to that of the light distribution lens 12 by a combination of the light incident surface 121b and the light output surface 122b.

(Modification of holding member 22)
11 is a cross-sectional view of a holding member 22a which is a first modification of the holding member 22, and FIG. 12 is a bird's-eye view of the holding member 22a of FIG. The holding member 22 a has a convex portion 221 a corresponding to the convex portion 31 of the holding member 22. A reflective member 222a corresponding to the reflective member 13 is disposed on the holding member 22a.

  The difference between the holding member 22a and the holding member 22 is that the side surface 223a of the convex portion 221a is inclined toward the inside of the convex portion 221a along the direction from the top surface 224a to the bottom surface 225a. In the holding member 22, the side surface of the convex portion 31 is inclined toward the inside of the convex portion 31 along the direction from the bottom surface to the top surface 32.

  In other words, in the holding member 22a, the area of the top surface 224a is larger than the area of the bottom surface 225a of the convex portion 221a, while in the holding member 22, the top surface 32 is larger than the area of the bottom surface of the convex portion 31. The area of is smaller.

  Thus, by increasing the area of the top surface (mounting part) 224a on which the LED module 14 is mounted, the ratio of the outgoing light that is reflected by the top surface 224a and goes upward (the light emission direction of the LED module 14) is increased. can do.

  13 is a cross-sectional view of a holding member 22b, which is a second modification of the holding member 22, and FIG. 14 is a bird's-eye view of the holding member 22b of FIG. The holding member 22 b has a convex portion 221 b corresponding to the convex portion 31 of the holding member 22. A reflection member 222b corresponding to the reflection member 13 is disposed on the holding member 22b.

  The difference between the holding member 22b and the holding member 22 is that the side surface 223b of the convex portion 221b is not inclined toward the inside of the convex portion 221b along the direction from the top surface 224b to the bottom surface 225b. In the holding member 22, the side surface of the convex portion 31 is inclined toward the inside of the convex portion 31 along the direction from the bottom surface to the top surface 32.

  In other words, in the holding member 22b, the area of the bottom surface 225b and the area of the top surface 224b of the convex portion 221b are equal, while in the holding member 22, the area of the top surface 32 of the convex portion 31 rather than the area of the bottom surface. Is smaller.

  In addition, the modified example of the holding member 22 does not necessarily need to include a convex portion as described above. For example, the shape of the truncated cone may have a trapezoidal shape. Even in such a shape, by mounting the LED module 14 on the top surface thereof, the LED module 14 can be protruded from the LED module 14 in the light emitting direction, and the light can be directed to the rear of the illumination device 10. .

(Replacement of the light distribution lens 12)
As described above, the light distribution lens 12 has a lens function of causing a part of the light emitted from the LED of the LED module 14 to move its traveling direction from the light emitting direction to the rear of the illumination device 10. . In other words, any member that can diffuse light emitted from the LEDs of the LED module 14 in various directions can be used as an alternative to the lens function.

  15 and 16 are views showing a diffusion cover used for a known jujube sphere, FIG. 15 is a sectional view thereof, and FIG. 16 is a bird's eye view thereof.

  By replacing such a diffusion cover with the light distribution lens 12, a function equivalent to the lens function of the light distribution lens 12 can be realized. That is, by combining this diffusion cover and the globe cover 11, light from the highly directional LED module 14 can be diffused twice, and a wider light distribution can be realized.

  However, the diffusing cover diffuses light to direct the light emitted from the light bulb inside thereof in various directions. For this reason, depending on the degree of diffusion, this leads to a decrease in the luminous flux.

  For this reason, when using the said diffusion cover instead of the light distribution lens 12, you should pay attention to the diffusion degree. This is because, even if the light distribution characteristics are improved, if a desired light flux cannot be obtained, the function as an illumination device cannot be achieved.

(Effect of glove cover 11)
The effect of the glove cover 11 is demonstrated using FIG. FIG. 17A is a diagram corresponding to the comparative example of the globe cover 11, and FIG. 17B is a diagram corresponding to the globe cover 11.

  As shown in FIG. 17B, the globe cover 11 has a curved surface shape. In particular, the curved surface shape is defined by two curvature radii K and L. That is, it is composed of a first curved surface shape defined by the curvature radius K and a second curved surface shape defined by the curvature radius L. The effect of such a configuration can be understood by comparison with the comparative example shown in FIG.

  The globe cover 110 of the lighting device 100 shown in FIG. 17A is composed of a first curved surface shape defined by a curvature radius I and a second curved surface shape defined by a curvature radius J. However, the curvature radius I and the curvature radius J are the same curvature radius with the same center of curvature. That is, the glove cover 110 has a substantially spherical shape, as is apparent from FIG.

  Such a difference in shape brings the following difference between the two lighting devices 10 and 100.

  In general, the overall length of the lighting device is determined in advance by a standard or the like and cannot be freely changed. That is, the size of each member is inevitably determined within a predetermined overall length.

  Compare the two glove covers 11, 110. By using two different radii of curvature in the globe cover 11, the ratio of the illumination device 10 to the entire length of the illumination device 10 is smaller than that of the globe cover 110. That is, it can be said that other members can be enlarged by that amount.

  In the lighting device 10, taking advantage of this point, the heat dissipation effect of the lighting device 10 is increased by increasing the size of the heat dissipation member 23. That is, the heat dissipation member 23 (the length N) of the lighting device 10 is larger than the heat dissipation member 230 (the length M) of the lighting device 100, and an increase in the heat dissipation effect is expected.

  Of course, here, the case where the heat dissipating member 23 is enlarged has been described as an example, but of course, other members may be enlarged.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

3 Insulating ring 4 Base 10 Illumination device 11 Globe cover (cover member)
12 Light distribution lens (optical member)
13 Reflecting member 14 LED module (light emitting element)
15 Heat Dissipation Sheet Member 21 Cosmetic Ring 22 Holding Member 23 Heat Dissipation Member 24 Screw 25 Power Supply Module 26 Holder 31 Convex Part

Claims (3)

An LED module having an LED;
A holding member having a mounting portion for mounting the LED module;
Optical that is arranged in the light emitting direction of the LED, and enters the light emitted from the LED, and emits the incident light in the light emitting direction, the peripheral edge direction of the holding member, and the side opposite to the light emitting direction. A member,
A cover member disposed so as to cover the LED module, the holding member, and the optical member, and transmitting light emitted from the LED;
With
The optical member has a recess in the center of the surface on the light emitting direction side,
By projecting the mounting part in the light emitting direction of the LED, the light emitted from the optical member to the side opposite to the light emitting direction passes outside the peripheral part of the holding member. A lighting device characterized by that. An LED module having an LED;
A holding member having a mounting portion for mounting the LED module;
Optical that is arranged in the light emitting direction of the LED, and enters the light emitted from the LED, and emits the incident light in the light emitting direction, the peripheral edge direction of the holding member, and the side opposite to the light emitting direction. A member,
A cover member disposed so as to cover the LED module, the holding member, and the optical member, and transmitting light emitted from the LED;
A reflective member that reflects light from the LED reflected by the cover member;
With
By projecting the mounting part in the light emitting direction of the LED, the light emitted from the optical member to the side opposite to the light emitting direction passes outside the peripheral part of the holding member. A lighting device characterized by that. It has a cylindrical heat radiating part that radiates heat from the LED module,
The lighting device according to claim 1, wherein the mounting portion protrudes in a light emitting direction of the LED from an outer edge portion at an upper end of the heat radiating portion.