Lighting fixture

Abstract

Provided is a lighting fixture (10) having a simple configuration and capable of securing an appropriate irradiation range of a light-emitting element. A light diffusion material (25) constituting a lighting fixture (10) according to the present invention is a long member having a square cross-sectional shape, and includes therein a lens (30), a light-emitting element (21), a substrate (22), and a heat sink (60), all of which are long and have the same length as the light diffusion material (25). The lens (30) has substantially the same length as the light diffusion material (25), is disposed on the light emission side of the substrate (22) on which the light-emitting element (21) is surface-mounted, and deflects and emits light incident from the light-emitting element (21). The substrate (22) is a flat plate having a substantially rectangular parallelepiped shape on which the light-emitting element (21) is surface-mounted on one surface thereof. The heat sink (60) is disposed along the longitudinal direction of the substrate (22) on the opposite side of the surface of the substrate (22) on which the light-emitting element (21) is surface-mounted, and holds and also makes thermal contact with the substrate (22), thereby transferring the heat generated from the light-emitting element (21) and dissipating the heat to the outside.

Description

lighting fixtures

[0001] The present invention relates to a lighting fixture using a light emitting element such as an LED, which is used in a showcase or the like.

[0002] BACKGROUND ART A number of inventions have been proposed in the past in which a lighting fixture made of a light emitting element such as an LED is arranged in a showcase or the like.

[0003] JP 2016-114254 A JP 2018-26275 A JP 2018-49772 A

[0004] Patent Document 1 aims to provide a reach-in showcase that brightens the interior of a product display room without increasing the illuminance of the lamps illuminating the interior, thereby increasing customer purchasing motivation. The light from the lamps illuminating the interior of the product display room is reflected by a mirrored member to brighten the interior. However, Patent Document 1 does not adjust the placement of lighting fixtures or the direction of the emitted light. Patent Document 2 uses a long lens with a light-emitting element disposed therein, but the direction of the light emitted from the light-emitting element does not necessarily uniformly illuminate the interior of the showcase door. Patent Document 3 aims to efficiently illuminate products displayed on the display shelves rather than illuminating the entire interior of the case body in a refrigerated showcase, and is not intended to brightly illuminate products placed between the doors, which tend to be dark.

[0005] Therefore, the present invention aims to provide a lighting fixture for use in showcases and the like, which has a simple structure and can brightly illuminate the entire display shelf, including the merchandise displayed between the doors, by ensuring a sufficient illumination range of light emitted from a light-emitting element onto the merchandise displayed between the doors.

[0006] In order to achieve the above object, the lighting device of the present invention is characterized in that the light diffusing material is a long, rectangular member having a cross-sectional shape, and contains inside a lens, a light-emitting element, a substrate, and a heat sink, all of which are long and have the same length as the light diffusing material; the lens is arranged on the light-emitting side of the substrate on which the light-emitting element is surface-mounted, and deflects and emits light incident from the light-emitting element; the substrate is a flat plate with an approximately rectangular shape on one side of which the light-emitting element is surface-mounted; and the heat sink is arranged along the longitudinal direction of the substrate on the side opposite to the surface on which the light-emitting element is surface-mounted, and holds the substrate and is in thermal contact with it, transferring heat generated by the light-emitting element and radiating it to the outside.

[0007] According to the present invention, by using a lighting fixture that uses a light-emitting element such as an LED, it is possible to brightly illuminate not only the space between the doors of the showcase but also the entirety of the products displayed on the shelves.

[0008] FIG. 1 is a perspective view showing the appearance of a showcase in which a lighting fixture according to an embodiment is arranged. FIG. 2 is a cross-sectional view showing the showcase in accordance with the embodiment cut along the horizontal line A-A in FIG. 1. FIG. 3A is an overall view of the lighting fixture in accordance with the embodiment. FIG. 3B is a cross-sectional view showing the lighting fixture in accordance with the embodiment cut along the line B-B in FIG. 3A. FIG. 4A is an explanatory diagram showing an example of the diffusion direction of light of the lighting fixture in accordance with the embodiment. FIG. 4B is an explanatory diagram showing an example of the diffusion direction of light of the lighting fixture in accordance with the embodiment. FIG. 4C is an explanatory diagram showing an example of the overall diffusion direction of light of the lighting fixture in accordance with the embodiment. FIG. 4D is an explanatory diagram showing an example of the overall light distribution state of the light of the lighting fixture in accordance with the embodiment. FIG. 5 is a partial cross-sectional view of a lighting fixture according to a modified example. FIG. 6A is an overall view of a lighting fixture according to a conventional example. FIG. 6B is a cross-sectional view showing the lighting fixture in accordance with the conventional example cut along the horizontal line C-C in FIG. 6A.

[0009] Next, an embodiment of a lighting fixture of the present invention will be described with reference to the drawings. The following example shows a specific example of the present invention, and the layout, functions, and numerical values ​​of the components described in the example are merely examples and should not be construed as limiting the scope of the present invention. Furthermore, components such as wiring, screws, and connectors are generally omitted from the drawings. In the following figures, identical parts are designated by the same reference numerals.

[0010] Here, a conventional example will be described. FIG. 6A is an overall view of a conventional lighting fixture 110, and FIG. 6B is a cross-sectional view of the conventional lighting fixture 110 taken along the horizontal line C-C in FIG. 6A. As shown in FIG. 6A, the lighting fixture 110 is a long, straight-tube LED lamp and is used as a lighting fixture 110 for a showcase 1 (see FIG. 1) installed in a store or the like. As shown in FIG. 6A, the lighting fixture 110 has mounting portions 112 at both ends for installation in predetermined locations in the showcase 1 (see FIG. 1), and a connector 111 at one end for connection to a power source. Furthermore, as shown in FIG. 6B, the lighting fixture 110 is composed of a substrate 122 on which a light-emitting element 121 embedded in a light diffusing material 125 is surface-mounted, and a heat sink 160 that holds the substrate 122. Since the conventional lighting fixture 110 does not have a lens 30 (see, for example, FIG. 3B ) as in this embodiment, the light emitted from the light-emitting element 121 is diffused evenly to the front surface through the light diffusing material 125. This has the drawback that the light does not reach products placed on shelves 4 between the doors (see, for example, door 3 of showcase 1 in FIG. 1 ). This embodiment overcomes this drawback, and by using a lighting fixture 10 equipped with a lens 30, it is possible to brightly illuminate the entire product displayed on shelves 4 as well as the area between the doors of the showcase 1.

[0011] FIG. 1 is a perspective view showing the exterior of a showcase 1 in which a lighting fixture 10 according to an embodiment is installed, and FIG. 2 is a cross-sectional view showing the showcase 1 in the embodiment cut along the horizontal line A-A in FIG. 1. As shown in FIG. 1, the showcase 1 includes a door 3, a shelf 4, and a handle 5. As shown in FIG. 2, the door 3 is made up of three doors 3a, 3b, and 3c that can be opened and closed, and multiple shelves 4 are arranged within the door 3. Each of the doors 3a-3c is provided with a handle 5a-5c, respectively, and is opened and closed by grasping and pulling the handle 5a-5c. Each of the doors 3a-3c is opened and closed by rotating horizontally via bearings (not shown) arranged at the upper and lower ends opposite the handles 5a-5c.

[0012] As shown in FIG. 2, lighting fixtures 10 are arranged vertically in the showcase 1. Lighting fixtures 10a and 10d are arranged near the bearing on the opposite side of the handle 5a of door 3a and near the bearing on the opposite side of the handle 5c of door 3c, respectively. Lighting fixtures 10b and 10c are arranged between doors 3a and 3b and between doors 3b and 3c, respectively. In this embodiment, a total of four lighting fixtures 10a-10d are arranged. As shown in FIG. 2, lighting fixtures 10a-10d brightly illuminate the area near the center of shelves 4 on which products and the like are placed (light-concentrated areas 15a, 15b, 15c). In the embodiment, an example is shown in which three doors 3a-3c are arranged in the showcase 1 and lighting fixtures 10a-10d are arranged on both sides of the doors 3a-3c, respectively. However, this is not limiting, and if there is more than one door 3, lighting fixtures 10a-10d can be arranged on both sides of each door 3.

[0013] Fig. 3A is an overall view of lighting fixture 10 according to the embodiment, and Fig. 3B is a cross-sectional view of lighting fixture 10 according to the embodiment taken along line B-B in Fig. 3A. As shown in Fig. 3A, lighting fixture 10 is a long, straight-tube LED lamp, and is used as lighting fixture 10 for a showcase 1 installed in a store or the like. As shown in the figure, lighting fixture 10 has mounting portions 12 at both ends for installation in predetermined locations on showcase 1, and a connector 11 at one end for connection to a power source.

[0014] The lighting fixture 10 is a straight tube lamp, and includes a substrate 22, a light diffusing material 25, a lens 30, and a heat sink 60, all of which are elongated and have approximately the same length. A light emitting element 21, such as an LED, is surface-mounted on the substrate 22. Both ends of the light emitting element 21, substrate 22, light diffusing material 25, lens 30, and heat sink 60 are fixed to mounting portions 12. The lighting fixture 10 emits light emitted from the light emitting element 21 through the lens 30 and the light diffusing material 25, brightly illuminating products and the like stored in the showcase 1.

[0015] 3B , the light diffusing material 25 has a generally rectangular parallelepiped shape with a generally square cross section along the longitudinal direction, and the top surface 26 has a gently convex shape. The light diffusing material 25 has protrusions 25a and 25b on both side surfaces 32a and 32b, which are convex inward along the longitudinal direction. The protrusions 25a and 25b serve to position the lens 30 and to fix the heat sink 60 inside the light diffusing material 25. The light diffusing material 25 may also be a transparent material.

[0016] The heat sink 60 has a gutter-shaped cross section with an open top, and a pair of convex portions 61a, 61b that grip the substrate 22 toward the inside are formed on both side surfaces of the top side. The substrate 22 is held between the convex portions 61a, 61b and the heat sink 60 so as to be in surface contact with the upper surface 62 of the heat sink 60. The heat sink 60 transfers heat generated from the light-emitting elements 21, such as LEDs, and dissipates the heat to the outside through the light diffusing material 25. Note that the cross section of the upper surface 26 of the light diffusing material 25 has a gently convex shape, but is not limited to this and may be other shapes, such as a flat shape or a concave shape.

[0017] The substrate 22 is a flat plate having a substantially rectangular parallelepiped shape that matches the shape of the light diffusing material 25, and has a plurality of light-emitting elements 21 surface-mounted in a row on one side. The light-emitting elements 21 may be arranged in parallel rows on the substrate 22, or may be arranged in an S-shape. The plurality of mounted light-emitting elements 21 are arranged on the surface of the substrate 22. A power supply unit (not shown) is arranged on the side of the substrate 22 opposite to the surface on which the light-emitting elements 21 are surface-mounted. Power is supplied from the connector 11.

[0018] The light-emitting element 21 is a substantially rectangular LED element, but may be an LED element of other shapes, such as square, circular, or diamond. The illumination light of the lighting fixture 10 is basically daylight white, but may be daylight, incandescent, or warm white depending on the products displayed in the showcase 1, and may be selected according to the application. Furthermore, a light source that emits a wavelength range that has sterilizing and anti-fungal effects may be used as the LED element. By using a light source with sterilizing effects, it is possible to efficiently sterilize, remove viruses, and prevent mold in the inner walls, shelves 4, and internal air of the showcase 1, as well as the displayed products.

[0019] Since LED elements emit light with higher directionality and brightness compared to fluorescent lamps, by arranging a light diffusing material 25 and a lens 30 so as to completely cover the mounting surface of the light emitting element 21, the light emitted from the light emitting element 21 is diffused in multiple directions and irradiated as uniform light onto products, etc.

[0020] The lens 30 is a member with a uniform cross-sectional shape in the transverse direction. As shown in FIG. 3B , the lens 30 has a generally M-shaped cross section cut vertically. The lens 30 is symmetrical about a vertical plane in the longitudinal direction that passes through a base point (center of the valley) 31c located at the bottom of the generally V-shape. The lens 30 has a pair of inclined surfaces that protrude in a generally V-shape from the base point 31c in the emission direction: a left-side inclined surface 31a as viewed from the front and a right-side inclined surface 31b as viewed from the front. The lens 30 also has a pair of side surfaces 32a, 32b that extend from the ends of the respective inclined surfaces 31a, 31b toward the substrate 22. Note that the inclined surfaces 31a, 31b are both flat inclined surfaces extending in the longitudinal direction, but may have a convex or concave lens shape or a knurled shape that protrudes in the light irradiation direction.

[0021] The lens 30 also has a pair of legs 33a, 33b connected to the pair of side surfaces 32a, 32b. The lens 30 facing the light-emitting element 21 has a bottom surface 35 located on the light-emitting element side of the base point 31c and above the light-emitting element 21. A pair of recesses 34a, 34b are formed between the pair of legs 33a, 33b on the base point 31c side and the bottom surface 35, and recessed toward the inclined surfaces 31a, 31b that are cut out of the lens 30. The bottom surface 35 is formed so as to be concave toward the light-emitting side of the light-emitting element 21, but is not limited to this.

[0022] In addition, a pair of notches 36a, 36b are formed on the leg portions 33a, 33b of the lens 30 on the light diffusing material 25 side, and the lens 30, the substrate 22 and the heat sink 60 are fixed together by the protrusions 25a, 25b of the light diffusing material 25.

[0023] 4A and 4B are explanatory diagrams showing an example of the light diffusion direction of the lighting fixture 10 in the embodiment. In FIG. 4A , light emitted from the light-emitting element 21 is irradiated inside the lens 30 in the direction indicated by the dotted line. Light emitted in a substantially vertical direction enters the lens 30, refracts to the right inside the inclined surface 31b, changes its direction of travel, and is irradiated to the right through the light diffusing material 25. Light emitted from the light-emitting element 21 toward the upper right enters the lens 30, refracts, and exits from the inclined surface 31b. As a result, the emitted light is diffused to the front right through the light diffusing material 25. In FIG. 4B , light emitted from the light-emitting element 21 is irradiated inside the lens 30 in the direction indicated by the dotted line. Light emitted to the right enters the lens 30, passes through the recess 34b, and light that enters the right of the lens 30 is refracted and diffused to the right through the side surface 32b and the light diffusing material 25.

[0024] 4C is an explanatory diagram showing an example of the overall diffusion direction of light from lighting fixture 10 in the example. In this figure, light emitted from light-emitting element 21 (solid line) is diffused in the vertical direction, and most of the light is diffused laterally by light diffusing material 25.

[0025] 4D is an explanatory diagram showing an example of the overall light distribution of the light from the lighting fixture 10 according to the embodiment. This diagram shows the light distribution characteristics when the light-emitting element 21 is placed in the center (0%) and the emission direction of the light-emitting element 21 is aligned downward (0 degrees) in the diagram. When the lens 30 according to the embodiment is used, the effective illumination range is a range of approximately 80 degrees to the left and right, demonstrating that effective illumination light is emitted over a wide range.

[0026] The lens 30 is long and has a uniform cross-sectional shape so as to fit the light diffusing material 25, and is manufactured by extrusion molding or the like. The lens 30 may be made of a resin such as polycarbonate, but is not limited thereto. It may also be made of an acrylic resin such as PMMA (polymethyl methacrylate), polystyrene, or the like. The shape and material of the lens 30 are not limited to those in the examples, as long as they can transmit light by changing the direction of irradiation of light from the light-emitting element 21. The surface of the lens 30 may be processed into a frosted glass or slit-like pattern to impart light diffusion and anti-glare properties. The lens 30 is not limited to a single long piece, but may be divided into multiple pieces.

[0027] 5 shows a component having a shape in which the light diffusing material 25 and the lens 30 are integrated, and is formed by two-color molding combining two different materials. In this case, the lens 30 is formed from a transparent material, and the light diffusing material 25 is formed from a material having light diffusing properties, but this is not limited to this. The material that integrates the lens 30 and the light diffusing material 25 can be, for example, a synthetic resin such as acrylic or polycarbonate resin, but is not limited to this.

[0028] The lighting fixture 10 according to the present embodiment irradiates light emitted from the light-emitting element 21 in multiple directions, ensuring a wide illumination range not only vertically but also horizontally and diagonally relative to the surface on which the light-emitting element 21 is mounted. The lighting fixture 10 is mounted between the doors 3 of a showcase 1 installed in a store, and the light-emitting element 21, such as an LED, thoroughly illuminates merchandise on the shelves 4 of the showcase 1. Because LEDs have high directivity, their emitted light often fails to reach merchandise placed on the shelves 4 between the doors 3, resulting in darkness between the lighting fixtures 10. However, by providing a lens 30, the lighting fixture 10 can illuminate in multiple directions. As a result, the lighting fixture 10 according to the present embodiment can ensure a wide illumination range. Furthermore, the lighting fixture 10 can be fitted to a lamp holder for a straight-tube fluorescent lamp or directly fixed to the showcase 1, eliminating the need for complex configurations such as positioning protrusions. Furthermore, the use of light-emitting element 21 that emits light with sterilizing, antifungal, and deodorizing properties can effectively sterilize merchandise. Therefore, the lighting fixture 10 can be suitably used, for example, as lighting for a showcase 1 installed in a store.

[0029] Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

[0030] This application claims priority based on Japanese Patent Application No. 2024-108341, filed on July 4, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0031] According to the present invention, a straight tube LED lighting fixture can emit light in multiple directions by using a lens to define the direction of light emitted by the light emitting element, thereby ensuring appropriate lighting in the showcase.

[0032] DESCRIPTION OF SYMBOLS 1... Showcase 3, 3a, 3b, 3c... Door 4... Shelf 5, 5a, 5b, 5c... Handle 10, 10a, 10b, 10c, 10d... Lighting fixture 11... Connector 12... Mounting portion 15a, 15b, 15c... Light concentration portion 21... Light emitting element 22... Substrate 25... Light diffusing material 25a, 25b... Protrusion 26... Top surface 30... Lens 31a, 31b... Inclined surface 31c... Base point 32a, 32b... Side surface 33a, 33b... Leg portion 34a, 34b... Recess 35... Bottom surface 36a, 36b... Notch 60... Heat sink 62... Top surface 61a, 61b... Convex portion 110... Lighting fixture (conventional example) 111... Connector 112... Mounting portion 121... Light emitting element 122: Substrate 125: Light diffusing material 160: Heat sink

Claims

1. A lighting fixture characterized in that the light diffusing material is a long, rectangular member with a rectangular cross section, and contains inside a lens, a light emitting element, a substrate, and a heat sink, all of which are long and have the same length as the light diffusing material; the lens is arranged on the light emitting side of the substrate on which the light emitting element is surface mounted, and deflects and emits light incident from the light emitting element; the substrate is a flat plate with a roughly rectangular parallelepiped shape and the light emitting element is surface mounted on one side; and the heat sink is arranged along the longitudinal direction of the substrate on the side opposite to the surface on which the light emitting element is surface mounted, and holds the substrate and is in thermal contact with it, transferring heat generated by the light emitting element and radiating it to the outside.

2. The lighting device according to claim 1, wherein the lens has a cross-sectional shape that is approximately M-shaped, and has a pair of inclined surfaces that jut out in an approximately V-shape in the light emission direction, with a base point located on the light emission side near the center of the light-emitting element mounted on the board as the center of a valley, a pair of side surfaces that continue from the inclined surfaces and hang down toward the board, a pair of legs that continue from the pair of side surfaces, a bottom surface that is located above the light-emitting element on the side of the base point, and a recess that is recessed toward the inclined surfaces between the base point and the bottom surface on the side of the legs.

3. The lighting fixture according to claim 1, wherein the heat sink has a gutter-shaped cross section with an open top, and a pair of protrusions are formed on both sides of the top facing inward, and the substrate is held between the pair of protrusions and the upper surface of the heat sink.

4. The lighting fixture according to claim 1, further comprising mounting portions at both ends for installation in predetermined locations on the showcase, and a connector at one end for connection to a power source.

5. The lighting fixture according to claim 1, further comprising a power supply device, said power supply device being arranged on the opposite side of said substrate to the surface on which said light emitting element is surface-mounted, and being connected to a power source.

6. A showcase according to any one of claims 1 to 5, wherein the lighting fixtures are installed near both ends of the door so as to brightly illuminate merchandise and the like displayed by the lighting fixtures.

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