Light unit and luminaire

Abstract

To provide a light unit using LEDs as light sources for suppressing the intrusion of insects and the remaining of the insects being dead inside a cover without providing new components or structures.SOLUTION: A support body of a light unit includes a long-sized plate part where an LED substrate having a plurality of LED packages installed side by side in the longitudinal direction is installed, and side parts provided on both lateral sides as both ends in the transverse direction of the plate part, respectively. A translucent resin cover includes a cover main part covering the LED substrate, a fitting part provided at each of both ends in the transverse direction of the cover main part while fitting the side part, and an end face part blocking each of both ends in the longitudinal direction of the support body. In the state that the LED packages are lit on, temperatures at both ends in the longitudinal direction of the support body and the temperatures of the side parts are each set to be 42°C or higher.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a lighting fixture that can suppress degradation of appearance caused by dead insects. [Background technology]

[0002] Conventionally, LED lighting fixtures have been known that are equipped with a light unit, also called a light source unit, and a fixture that is installed on a structure such as a ceiling and houses the light unit, and are configured by mechanically and electrically connecting the light unit and the fixture. LED is an abbreviation for Light Emitting Diode.

[0003] Light sources used in lighting fixtures are increasingly being replaced by energy-efficient LEDs, which have been replacing incandescent bulbs and fluorescent lamps.

[0004] The light unit is, for example, a housing that is a support body formed of a metal material, and an LED board with an LED package surface-mounted thereon is installed inside the housing. The support body on which the LED board is installed is surrounded by a light-transmitting resin cover that is formed of a resin material and has diffusive properties, and the brightness and diffusivity of the irradiated light are adjusted.

[0005] For example, in a long light unit, the translucent resin cover and the support are both formed in a long shape, and the translucent resin cover is fixed so as to sandwich both sides along the longitudinal direction of the support. In general, the translucent resin cover directly sandwiches and fixes the side of the support without interposing an adhesive or packing between the side of the support and the translucent resin cover. The long support and the translucent resin cover are each accompanied by deformation such as distortion or warping. Therefore, strictly speaking, there is a gap between the side of the support and the translucent resin cover in the longitudinal direction when the translucent resin cover is fixed to the side of the support, and the gap may expand depending on the degree of deformation of each.

[0006] It is considered problematic that small insects get into the lighting fixture through such gaps and remain dead inside the translucent resin cover. This can lead to a deterioration in the aesthetics or performance of the lighting fixture, and also, when a user looks up at the lighting fixture, they may feel uncomfortable seeing dead insects scattered like spots projected on the translucent resin cover. Therefore, this is an issue for lighting fixtures that needs improvement.

[0007] Patent document 1 discloses a lighting device having an elastically deformable resin connecting member that is placed in a gap formed between a base portion on which a light source portion is attached and a resin cover portion that covers the light source portion, and that seals this gap. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2017-174622 A Summary of the Invention [Problem to be solved by the invention]

[0009] In Patent Document 1, it is necessary to provide a new elastically deformable member in order to reduce the intrusion of insects and the like that are capable of deforming, which can be a factor in increasing the cost of the lighting fixture.

[0010] The present disclosure aims to prevent insects from entering a light unit that uses an LED as a light source, and to prevent insects from remaining as dead bodies inside a cover, without providing any new components or configurations. [Means for solving the problem]

[0011] The light unit according to the present disclosure includes: A support body including a plate portion on which an LED substrate having a plurality of LED packages arranged in a longitudinal direction is mounted, and side portions provided on both side edges of the plate portion, which are both ends in a short direction of the plate portion; a translucent resin cover including a cover main portion covering the LED board, fitting portions provided at both ends of the cover main portion in a short direction, the fitting portions fitting with the side portions, and end surface portions closing each end of both ends of the support body in a long direction; Equipped with With the LED package turned on, the temperatures at both ends in the longitudinal direction of the support and at the sides were set to 42° C. or higher. Effect of the Invention

[0012] In the light unit according to the present disclosure, when the LED package is turned on, the temperature of both ends and the temperature of the sides in the longitudinal direction of the support are set to 42° C. or higher. As a result, with the light unit according to the present disclosure, the temperature in the areas where insects may enter can be set to 42° C. or higher, suppressing insect intrusion and suppressing insect carcasses from remaining inside the cover. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a perspective view of a lighting fixture according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view showing the lighting fixture according to the first embodiment in a separated state before the fixture and the light unit are integrated together. [Diagram 3] 2A and 2B are a plan view and a side view of the light unit according to the first embodiment as viewed from the main body side and the light unit as viewed from the side, respectively. [Figure 4] 1 is a cross-sectional view of a lighting fixture according to a first embodiment. [Diagram 5] FIG. 2 is a diagram showing a support on which an LED substrate according to the first embodiment is mounted. [Figure 6] FIG. 11 is a diagram showing a temperature distribution in the short side direction of a support in a comparative test according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] ***Background of this Disclosure*** First, the background of the present disclosure will be described. Fluorescent lamps used as light sources for lighting fixtures have the characteristic that their luminous efficiency changes depending on the temperature of the environment (around the fluorescent lamp). A typical fluorescent lamp uses ultraviolet light generated by low-pressure mercury discharge as excitation light, and uses visible light generated by exciting phosphors laid on the inner surface of a glass tube as illumination light. The mercury vapor pressure inside the glass tube is determined by the coldest point, which is the lowest temperature in the discharge space. If the temperature of the coldest point is too low, the mercury vapor pressure will be low and excitation will be difficult, resulting in low luminous efficiency. If the temperature of the coldest point is too high, a self-absorption phenomenon will occur in which ultraviolet light is absorbed by other mercury atoms before it reaches the phosphor, resulting in low luminous efficiency. In other words, optimization of the coldest point temperature is an essential element for fluorescent lamps, and this optimization of the coldest point temperature is basically an element that is completed by the fluorescent lamp, regardless of the lighting unit itself. In addition, fluorescent lamps are mainly made of glass and metal, and the temperature of the materials themselves does not affect the product life of the fluorescent lamp.

[0015] LEDs used as light sources in lighting fixtures have the characteristic that their luminous efficiency is high and does not change depending on the temperature of the environment (around the LED). LEDs are semiconductor light-emitting elements, and in order to maintain their performance, they must be used so that their junction temperature (hereafter referred to as Tj) remains within a specified range (below the rated value), which is an essential element of LEDs. In general, in order to keep the temperature of LEDs within a specified range, a method is adopted in which the heat generated by the LED during lighting is dissipated using a heat sink or the like. In other words, the temperature control of the LED, which is a light source, is dependent on components other than the light source.

[0016] Also, there is one difference between using lighting fixtures that use LEDs as light sources and those that use fluorescent lamps as light sources. That is, the LED itself, which is the light source, has an exposed charging part. Considering safety, it is preferable for lighting fixtures to be designed so that users cannot touch the exposed charging part, and safety is ensured by making the structure of the lighting fixture such that the translucent resin cover cannot be easily removed. On the other hand, lighting fixtures that use fluorescent lamps as light sources have no exposed charging part, and because fluorescent lamps have a shorter lifespan than LEDs, the lighting fixture's translucent resin cover is designed to be easily removed so that the fluorescent lamp, which is the light source, can be replaced. In other words, LEDs have a long lifespan and do not need to be replaced like fluorescent lamps, while fluorescent lamps are consumables that need to be replaced. This difference leads to a difference in the structure of the lighting fixture.

[0017] For this reason, in lighting fixtures that use LEDs as light sources, the problem of insect carcasses that have invaded the interior of the fixture has arisen. In general lighting fixtures used in facilities such as offices, the LED light source is covered with a translucent cover, and the cover ensures insulation (safety) for the exposed live parts of the LED, and is structured so that it cannot be easily removed. LEDs have fewer short-wavelength and ultraviolet components than fluorescent lamps, so they are less insect-attracting than fluorescent lamps, but there are insects that are attracted to the lighting fixture and invade the interior of the fixture, and there are also insects that remain dead inside the translucent cover. In lighting fixtures that use fluorescent lamps as light sources, the translucent cover can be removed when replacing the fluorescent lamp, so foreign objects that remain inside the cover can be removed. However, there is a problem in that foreign objects cannot be removed in general lighting fixtures that use LEDs as light sources.

[0018] For example, it is possible to cover the LED with a lens or sealant other than the cover, creating a structure that allows the cover to be attached and detached so that foreign objects can be removed, or to attach the cover with a structure that ensures a high level of airtightness so that foreign objects, including insects, cannot enter the interior of the lighting fixture; however, either approach would inevitably increase costs and is not realistic. It is also possible to provide a lighting fixture with an openable lid at the end of the cover, so that foreign objects remaining inside the cover can be removed by opening the lid, but performing such a procedure on a large number of lighting fixtures installed in an office or the like requires a considerable amount of time and maintenance costs. For this reason, there is a demand for lighting fixtures that can prevent insects from entering.

[0019] Hereinafter, the present embodiment will be described with reference to the drawings. In each drawing, the same or corresponding parts are given the same reference numerals. In the description of the embodiment, the description of the same or corresponding parts will be omitted or simplified as appropriate. In addition, the relationship of the size of each component in the following drawings may differ from the actual one. In addition, in the description of the embodiment, directions or positions such as up, down, left, right, front, back, front, and back may be indicated. These notations are for the convenience of explanation and do not limit the arrangement, direction, or orientation of devices, instruments, parts, etc.

[0020] Embodiment 1 ***Configuration Description*** The configuration of lighting device 10 according to the present embodiment will be described below with reference to Figs. 1 to 4. FIG. 1 is a perspective view of a lighting fixture 10 according to the present embodiment. FIG. 2 is a perspective view showing a state in which the lighting fixture 11 and the light unit 12 are separated and not yet integrated in the lighting fixture 10 according to the present embodiment. FIG. 3 is a plan view of the light unit 12 according to the present embodiment as viewed from the main body side and a side view as viewed from the side. FIG. 4 is a cross-sectional view of lighting device 10 according to the present embodiment.

[0021] The lighting fixture 10 includes a fixture 11 and a light unit 12 that is detachably attached to the fixture 11. The device 11 is mounted on a structure 20 such as a ceiling. The fixture 11 includes an attachment portion 110 for attaching the light unit 12. The attachment portion 110 is provided with an attachment spring 111 for attaching the light unit 12. Furthermore, the attachment portion 110 is provided with a fixture power line 112 which serves as a path for supplying external power from the outside of the lighting fixture 10 to a power supply unit 124 included in the light unit 12.

[0022] The light unit 12 includes a support 121, an LED substrate 122, a light-transmitting resin cover 123, and a power supply unit 124. In this embodiment, a long light unit 12 will be described as an example. The LED substrate 122 has an elongated shape, and a plurality of LED packages 221 are arranged along the longitudinal direction.

[0023] The support 121 is a housing of the light unit 12. The support 121 is elongated and includes a plate portion 212 on which the LED board 122 is installed, and side portions 211 provided on both side edges, which are both ends of the plate portion 212 in the short direction. 4, the support 121 is a metal plate having a generally concave cross section, and has side portions 211 corresponding to the sides of the concave shape and a plate portion 212 corresponding to the bottom of the concave shape. An LED substrate 122 is installed on a surface of the support 121 facing the irradiation direction of the plate portion 212.

[0024] The light-transmitting resin cover 123 is attached to the side portion 211 of the support 121 so as to cover the LED board 122 . The light-transmitting resin cover 123 includes a cover main part 233 that covers the LED substrate 122, fitting parts 231 that fit with the side parts 211 of the support 121, and end surface parts 232 that are provided so as to close each end part in the longitudinal direction. The fitting parts 231 are provided in the longitudinal direction at each end part of the short side direction of the cover main part 233, and fit with the side parts 211 of the support 121. End surfaces 232 serving as end plates are ultrasonically welded to both longitudinal ends of the light-transmitting resin cover 123 . The light-transmitting resin cover 123 and the end surface portion 232 are formed using a resin material such as polycarbonate (PC).

[0025] In addition, on the side of the support 121 opposite to the side on which the LED substrate 122 is installed on the plate portion 212, which is the side of the fixture 11 (hereinafter referred to as the main body side), there are installed a power supply unit 124 that supplies lighting power to the multiple LED packages 221 via the LED substrate 122, and a spring support 125 that connects to the mounting spring 111 of the fixture 11. The light unit 12 is connected and integrated with the fixture 11 by engaging the mounting spring 111 with the spring receiver 125. Specifically, when the mounting spring 111 is inserted into the spring insertion portion 126, which is a through hole provided in the spring receiver 125, and the light unit 12 is pushed toward the fixture 11, the elastic force of the mounting spring 111 draws the light unit 12 into the mounting portion 110 of the fixture 11, and the light unit 12 is attached to the fixture 11.

[0026] Furthermore, the fixture power line 112 is connected to a unit power line 127 connected to the power supply unit 124, thereby making it possible to supply external power to the power supply unit 124. In this manner, the fixture 11 and the light unit 12 are mechanically and electrically connected. There are various means for this mechanical connection and electrical connection, and any means may be selected.

[0027] 4 shows a configuration in which fixture 11 and light unit 12 are integrated, mechanically and electrically connected, and used as lighting fixture 10. When light unit 12 is not turned on, lighting fixture 10 thus integrated does not generate heat, and all of the components constituting lighting fixture 10 are at temperatures roughly close to the ambient temperature.

[0028] <Variations of Support 121> FIG. 5 is a diagram showing a support 121 on which an LED substrate 122 according to the present embodiment is mounted. An LED package 221 is surface-mounted on the mounting surface of the LED substrate 122. Then, the LED board 122 is placed on the plate part 212 of the support body 121 with the non-mounting surface of the LED board 122 in contact with the surface of the plate part 212 of the support body 121 facing the irradiation direction. FIG. 5 shows a portion of the support 121 on which the LED substrate 122 is mounted. FIG. 5 also shows a plan view (left) and a cross-sectional view (right) of a portion of the support 121 as viewed from the irradiation direction.

[0029] FIG. 5 shows three examples in which the dimension in the short side direction of the LED board 122 mounted on the support 121 (hereinafter referred to as board width) is 17.2 [mm], 21.5 [mm], and 29.0 [mm]. A light unit 12 using an LED board 122 with a board width of 17.2 mm is taken as Example 1. A light unit 12 using an LED board 122 with a board width of 21.5 mm is taken as Example 2. A light unit 12 using an LED board 122 with a board width of 29.0 mm is taken as Example 3.

[0030] Here, it is assumed that the LED substrate 122 is made of a material containing paper, glass, and resin, and has a thickness of 1.0 [mm]. It is preferable to use a material having a flame retardancy equivalent to CEM-3 or higher. In addition, it is assumed that the support 121 is made of SGCC steel plate having a thickness of 0.4 [mm], but the material is not limited to this, and materials other than SGCC steel plate may be selected. SGCC is an abbreviation for Steel Galvanized Cold Commercial.

[0031] In addition, the support 121 preferably has a width of 67.0 mm or less in the short side direction so as not to prevent the light unit 12 and the fixture 11 to which the light unit 12 is attached from being made smaller or lighter. The light unit 12 and the fixture 11 are made smaller or lighter, which contributes to improving workability or transportation efficiency. FIG. 5 illustrates a support 121 having a width of 56.0 mm in the short side direction. Silicone is applied to the area of ​​the support 121 where the LED substrate 122 is installed, and the LED substrate 122 is placed and pressed down to make the LED substrate 122 adhere to the support 121. The method of installing the LED substrate 122 on the support 121 is not limited to adhesion using silicone, but may also be to cut out a plurality of claw-shaped portions on both sides of the area of ​​the support 121 where the LED substrate 122 is installed, and raise the claws to press down the LED substrate 122 to make it adhere to the support 121. Alternatively, the LED substrate 122 may be screwed to the support 121. In short, it is sufficient that the LED substrate 122 and the support 121 are in close contact with each other.

[0032] <Light Unit 12 Behavior> Next, in order to specifically explain the measures taken against insect intrusion in lighting fixture 10 according to the present embodiment, the behavior of light unit 12 will be described. The light unit 12 is, for example, a 40-type light unit with multiple LED packages 221 surface-mounted at approximately equal intervals on the LED substrate 122, consuming approximately 10 W to approximately 50 W of power and emitting a light color with a color temperature of 2700 K to 6500 K. The LED substrate 122 has as few as 68 LED packages 221 surface-mounted, and as many as 240 LED packages 221 surface-mounted.

[0033] The power supply unit 124 converts the external power received from the fixture 11 side via the fixture power line 112 and the unit power line 127 into lighting power for lighting the LED package 221, and when the lighting power is supplied from the power supply unit 124 to the LED package 221, the LED package 221 lights up. When the light unit 12 is turned on, light is emitted from a plurality of LED packages 221 mounted on a linear LED substrate 122. This light is emitted to the outside of the light unit 12 through a translucent resin cover 123 made of resin, and is provided as illumination light. Meanwhile, the LED packages 221 generate heat as they are turned on, and this heat is conducted from the LED substrate 122 to the support 121 on which the LED substrate 122 is mounted. Then, the temperature of the contact portion between the support 121 and the LED substrate 122 is increased, and the heat is conducted to the side portion 211 of the support 121, and further to the light-transmitting resin cover 123 that is fitted with the side portion 211. In this way, the heat generated by the LED package 221 is conducted to each part as time passes after lighting, causing the temperature of various components to rise. However, after about 60 minutes, the heat is balanced with the heat radiation from the light unit 12, and the temperature of each part becomes stable.

[0034] Since the light unit 12 is elongated, the support 121 and the light-transmitting resin cover 123 are also elongated. Therefore, the side parts 211 at both ends in the short direction (width direction) of the support 121 and the fitting parts 231 of the light-transmitting resin cover 123 that fit into the side parts 211 come into contact over a long portion. In addition, the ends at both ends in the longitudinal direction of the support 121 come into contact with the light-transmitting resin cover 123. Although the support 121 and the translucent resin cover 123 are fitted and in contact with each other, they are not bonded with an adhesive or have a packing sandwiched therebetween. Therefore, strictly speaking, there is a gap between the support 121 and the translucent resin cover 123. Furthermore, if the lighting fixture is long, the long support 121 and the translucent resin cover 123 are deformed, such as twisted, distorted, or warped, due to molding conditions, thermal expansion, and the like. Therefore, when the translucent resin cover 123 is fixed to the side portion 211 of the support 121, the gap may expand depending on the degree of deformation of each. When designing the lighting fixture 10, no gaps that allow insects to enter are intentionally provided. However, in many lighting fixtures, small insects enter through such gaps. Compared to fluorescent lamps, LEDs emit less ultraviolet light or short-wavelength blue light that stimulates insect activity. However, the problem of insects entering through gaps has not been completely solved.

[0035] <Explanation of the comparative test> Next, comparative tests of Examples 1 to 3 will be described using a more specific lighting fixture as an example. A direct-mounted inverted Fuji 150 mm wide luminaire 10 was installed on a simulated ceiling in a temperature-controlled room with a constant ambient temperature of 25°C and no wind. All luminaires 10 used in the comparison test were standardized to have a length of 4 ft (approximately 1.2 m), a total luminous flux of 5900 lm, and a light source color with a color temperature of 5000 K. The luminaires 10 used SGCC with a thermal conductivity of 50 [W / m K] as the material for the support 121, and the support 121 had a constant width of 56.0 [mm] and a thickness of 0.4 [mm]. The same DC current of 100 mA was supplied to the LED package 221 in all cases, and approximately 40 W was input.

[0036] As shown in FIG. 5, a comparative test was carried out on three types of lighting fixtures using three types of LED substrates 122 with substrate widths of 29.0 [mm], 21.5 [mm], and 17.2 [mm]. The reason for taking the board width as a parameter is as follows. In the three types of LED boards 122 with different board widths, the LED packages 221 are surface-mounted at the same intervals and with the same length. However, even if the heat generated by the LED packages 221 themselves is the same, the heat conduction to the support 121 functioning as a heat sink varies depending on the board width. For this reason, if the board width is small (the board is thin), the temperature of the support 121 as a whole increases. Conversely, if the board width is large (the board is thick), heat is conducted in a wide area, so the temperature of the support 121 as a whole decreases. In this way, the temperature of the side portion 211 of the support 121 can be controlled by changing the board width of the LED board 122, so here, the board width of the LED board 122 is taken as a parameter. In other words, it has been shown that the phenomenon that the temperature of the side portion 211 of the support 121 can be controlled by the board width can be used as a means for setting the temperature of the side portion 211.

[0037] On the LED board 122 of any board width, white LED packages 124 of about 0.3 W each are surface-mounted at approximately equal intervals. The temperature of each part of the support 121 was measured by installing multiple thermocouples on the opposite side to the surface on which the LED substrate 122 was installed, at a position sufficiently far away from other heat sources such as the power supply unit 124. The reason for this is as follows. The power supply unit 124 also generates heat, and if this heat is superimposed, the temperature will become higher. However, there is a possibility that insects may invade anywhere on the side portions 211 on both sides of the long support 121. Therefore, the periphery that is not affected by the heat generated by the power supply unit 124, in other words, the periphery where the temperature of the side portions 211 of the support 121 is the lowest, was selected as the position for measuring the temperature of each part of the support 121.

[0038] As described above, the light-transmitting resin cover 123 is an extrusion molded product made of polycarbonate (PC), and the end face portions 232, which are end plates made of the same polycarbonate (PC), are ultrasonically welded to both ends in the longitudinal direction of the light-transmitting resin cover 123. The secondary transition temperature of polycarbonate (PC) is 145°C to 150°C, the deflection temperature under load is 123°C to 132°C, and the continuous use temperature is 130°C.

[0039] Thus, in the comparative test, three types of light units 12, Example 1 to Example 3, using three types of LED boards 122 with different board widths were used. The comparative test was performed in a combination in which each light unit 12 was mechanically and electrically connected to the fixture 11 and the lighting fixture 10 was used. Temperature measurements were performed 60 minutes after power-on when the temperature had sufficiently stabilized.

[0040] If the ratio of the dimension (board width) in the short side direction of the LED board 122 to the dimension (width) in the short side direction of the support 121 is defined as the occupancy rate, it is as follows. Example 1 The occupancy rate of the LED board 122 with a board width of 17.2 mm is 17.2 mm / 56.0 mm=30.7%. Example 2 The occupancy rate of the LED board 122 with a board width of 21.5 mm is 21.5 mm / 56.0 mm=38%. Example 3 The occupancy rate of the LED board 122 with a board width of 29.0 mm is 29.0 mm / 56.0 mm=51.8%.

[0041] In this comparative test, SGCC with a thermal conductivity of approximately 50 [W / m·K] was used for the support 121. For example, aluminum has excellent thermal conductivity of 200 [W / m·K], which further reduces the temperature of the support 121. Conversely, SUS material (stainless steel) has a relatively low thermal conductivity of approximately 16 to 25 [W / m·K], which tends to increase the temperature of the support 121. For this reason, in addition to using the width of the LED board 122 as a design element, the temperature of the side portion 211 of the support 121 can also be controlled by selecting the support material. Furthermore, increasing the thickness dimension of support 121 increases the thermal conductivity and decreases the temperature of side portion 211 of support 121, and conversely, decreasing the thickness decreases the thermal conductivity and reduces the heat dissipation performance, thereby increasing the temperature of side portion 211 of support 121. In this way, the temperature of side portion 211 of support 121 can also be controlled by adjusting the thickness of the support.

[0042] FIG. 6 is a diagram showing the temperature distribution in the short side direction of support 121 in a comparative test according to this embodiment. 6, the temperatures at both ends of the graph at the support position are the temperatures of the portion fitted with the translucent resin cover 123, i.e., the temperatures of the side portions 211 of the support 121 (support side temperature). In other words, they are the temperatures of the portions that serve as paths for insects to pass through the gaps and enter the inside of the translucent resin cover 123 of the light unit 12. As shown in FIG. 6, the support edge temperatures are as follows: Example 1 When an LED substrate 122 having a substrate width of 17.2 mm is used, the temperature of the side portion 211 of the support 121 is approximately 49.4°C. Example 2 When an LED substrate 122 having a substrate width of 21.5 mm is used, the temperature of the side portion 211 of the support 121 is approximately 41.5°C. Example 3 When an LED substrate 122 having a substrate width of 29.0 mm is used, the temperature of the side portion 211 of the support 121 is approximately 37.9°C.

[0043] Up to this point, the temperature of the side portion 211 of the support 121 has been described, but the temperature of both ends of the support 121 in the longitudinal direction is also almost the same as that of the side portion 211 for each board width. In this way, both sides in the short direction of the support 121 and both ends in the longitudinal direction of the support 121 are at almost the same temperature, which is effective as a method of suppressing insect intrusion. Here, if attention is paid only to the temperature of the side portion 211 of the support 121, the junction temperature Tj of the LED package 221 for maintaining the life of the light unit 12 may become too high, shortening the product life. For this reason, it is desirable to design the support 121 taking into consideration both the temperature of the side portion 211 and the junction temperature Tj.

[0044] When the width of the substrate was narrowed from 29.0 mm to 21.5 mm, the peak temperature rose, and the temperature of the edge 211 of the support 121 also rose from 37.9° C. to 41.5° C., but did not exceed the protein denaturation temperature of 42° C. When the width of the substrate was narrowed further to 17.2 mm, the temperature of the edge 211 of the support 121 rose to 49.4° C., which is above 48° C., a temperature at which insects cannot generally survive. For this reason, it becomes difficult for insects to approach the side 211 of the support 121, and even if they do remain on the side 211 of the support 121, their survival time becomes extremely short, so that it becomes difficult for insects to pass through the gap between the support 121 and the light-transmitting resin cover 123 and enter the internal space of the light unit 12.

[0045] So far, a method for controlling the temperature of the side portion 211 of the support 121 and both ends in the longitudinal direction of the support 121 by changing the board width of the LED board 122 has been described. There are various other methods for controlling the temperature of the side portion 211 of the support 121 and both ends in the longitudinal direction of the support 121. For example, the temperature gradient of the support 121 may be changed by changing the material or thickness of the support 121. Also, the power supplied to the LED package 221 may be changed. Furthermore, a means for changing the number of LED packages 221 used may be used in order to change the power supplied to the LED packages 221.

[0046] The main point of this embodiment is to make the temperature of the gap, which can be an entry route for insects, higher than the temperature at which proteins denature, in order to prevent insects from approaching the gap and trying to get into the interior of lighting fixture 10 or light unit 12 through the gap. Furthermore, the temperature is set at such a level that insects that still try to pass through the gap die within the time it takes to pass through. This makes it possible, in principle, to prevent insects from entering the interior of lighting fixture 10 or light unit 12.

[0047] As described above, in this embodiment, lighting fixture 10 that suppresses the intrusion of insects has been described. In lighting device 10 according to the present embodiment, when LED package 221 is turned on, the temperature at both ends and both sides (sides 211 on both sides) in the longitudinal direction of support 121 is set to 42°C or higher. This makes it difficult for insects to approach. Furthermore, it is preferable that the temperature at both ends and both sides (sides 211 on both sides) in the longitudinal direction of support 121 is set to 48°C or higher.

[0048] Furthermore, in the lighting fixture 10 according to the present embodiment, the occupancy rate of the short-side dimension (board width) of the LED board 122 relative to the short-side dimension (width) of the support 121 is 38% or less. For example, when the width of the support 121 is 56.0 mm, 38% of the width is 21.28 mm. Therefore, when the width of the support 121 is 56.0 mm, it is preferable that the board width of the LED board 122 is 21.28 mm or less.

[0049] Furthermore, in lighting device 10 according to the present embodiment, support 121 preferably includes a material with a thermal conductivity in the range of 14 [W / m·K] to 300 [W / m·K]. Furthermore, in lighting device 10 according to the present embodiment, support 121 more preferably has a thermal conductivity of 50 [W / m·K] or less.

[0050] Moreover, it is preferable that the temperature of the portion of the light-transmitting resin cover 123 that contacts the side portion 211 is equal to or lower than the continuous heat resistance temperature of the resin used. This can prevent the product life of the light unit 12 from being shortened.

[0051] ***Explanation of the Effects of the Present Embodiment*** As described above, in the light unit 12 according to the present embodiment and the lighting fixture 10 equipped with this light unit 12, the light-transmitting resin cover 123 is structured so as not to easily come off the support 121, and there is no structure for removing the carcasses of invading insects, so it is possible to prevent insects from entering the light unit 12 without using any new parts or configuration. A new configuration for preventing insects from entering is, for example, a packing that prevents insects from entering or a part or portion that closes a deformable gap, which would increase the cost of the lighting fixture 10.

[0052] Therefore, according to the light unit 12 of this embodiment and the lighting fixture 10 equipped with this light unit 12, even in the lighting fixture 10 in which the translucent resin cover 123 cannot be easily removed and the end plate (end surface portion 232) at the end thereof is also integrated with the translucent resin cover 123 and cannot be separated, degradation of appearance or performance due to dead insects can be suppressed without increasing costs.

[0053] The effects of the lighting fixture according to this embodiment will now be described in more detail. The insects' entry paths are the gaps at both sides (sides 211 on both sides) and both ends in the longitudinal direction of the support 121 through which heat is conducted from the LED substrate 122 fixed to the support 121, and the gap at the fitting portion of the translucent resin cover 123. In the case of a lighting fixture 10 that uses an LED as a light source, the support 121 also functions as a heat sink for the purpose of lowering the junction temperature Tj of the LED package 221, and its temperature rises as the light unit 12 is turned on. For this reason, it is thought that the entry of insects can be suppressed by raising the temperature of the gaps that serve as insect entry paths to a temperature at which insects cannot enter.

[0054] Here, the posture of the insect when it enters the gap will be described. When light unit 12 was vibrated while glass beads of different diameters were sprinkled into the gaps in light unit 12 in the lit state, the maximum diameter of the glass beads that penetrated inside translucent resin cover 123 of light unit 12 was φ0.3 mm or less. When designing lighting fixture 10, no gaps that would allow insects to enter were intentionally created, but it was found that gaps did occur when light unit 12 was lit, and that these gaps were 0.3 mm or less in size. However, some of the insects that actually entered the interior of the lighting fixture 10 had head, thorax, and torso dimensions that were larger than 0.3 mm. In other words, the insects need to flatten their bodies when entering a gap. From this, it is presumed that the insects do not stay with only their feet touching the high-temperature support 121, but stay in a position that is susceptible to the effects of heat. Therefore, the insects enter and pass through the gap with most of their bodies in close contact with the support 121 and the light-transmitting resin cover 123.

[0055] If the temperature of the support 121 is 42°C or higher, at which proteins are denatured and insects generally cannot survive, the insects cannot continue to live. Furthermore, it is preferable to set the temperature at 48°C or higher so that when an insect approaches and comes into contact with the support 121, it dies in a shorter time than it takes for it to pass through the gap.

[0056] Insects attracted to the lighting fixture 10 by the insect-attracting properties of the light will sense the danger to their lives and will not approach the high-temperature gap. Even if an insect tries to enter the gap, it will die before passing through the gap, so it is prevented from entering the inside of the light unit 12 and from remaining as a corpse inside the translucent resin cover 123. This prevents the deterioration of the aesthetics or performance of the lighting fixture 10, and the spotted corpses projected on the translucent resin cover become less noticeable, which has the effect of preventing discomfort to the user. The temperature of the fitting portion 23 of the translucent resin cover 123 in contact with the side portion 211 of the support 121 is set to be equal to or lower than the continuous heat resistance temperature of the resin material used for the fitting portion 23, so that the deterioration of the translucent resin cover 123, which is a resin part, can be prevented, and there is no adverse effect on the product life and safety of the lighting fixture 10.

[0057] Of the above-described embodiments, a plurality of parts may be combined to be implemented. Alternatively, one part of the embodiments may be implemented. In addition, these embodiments may be combined in any manner, either as a whole or in part, to be implemented. That is, in the first embodiment, the embodiments can be freely combined, or any of the components in each embodiment can be modified, or any of the components in each embodiment can be omitted.

[0058] It should be noted that the above-described embodiment is essentially a preferred example, and is not intended to limit the scope of the present disclosure, the scope of application of the present disclosure, and the scope of use of the present disclosure. The above-described embodiment can be modified in various ways as necessary.

[0059] Various aspects of the present disclosure are summarized below as appendices.

[0060] (Appendix 1) A support body including a plate portion on which an LED substrate having a plurality of LED packages arranged in a longitudinal direction is mounted, and side portions provided on both side edges of the plate portion, which are both ends in a short direction of the plate portion; a translucent resin cover including a cover main portion covering the LED board, fitting portions provided at both ends of the cover main portion in a short direction, the fitting portions fitting with the side portions, and end surface portions closing each end of both ends of the support body in a long direction; Equipped with A light unit in which the temperature at both ends in the longitudinal direction of the support and the temperature at the sides are set to 42°C or higher when the LED package is turned on. (Appendix 2) 2. The light unit according to claim 1, wherein the support has a width in a short side direction of 67 mm or less. (Appendix 3) 3. The light unit according to claim 1 or 2, wherein the support is made of metal. (Appendix 4) The light unit according to any one of claims 1 to 3, wherein the occupancy rate of the width of the LED substrate in the short side direction relative to the width of the support in the short side direction is 38% or less. (Appendix 5) 5. The light unit according to claim 1, wherein the support includes a material having a thermal conductivity in the range of 14 [W / m·K] or more and 300 [W / m·K] or less. (Appendix 6) 5. The light unit according to claim 1, wherein the support has a thermal conductivity of 50 [W / m·K] or less. (Appendix 7) 7. The light unit according to claim 1, wherein the temperature of both ends and the side portions in the longitudinal direction of the support is set to 48° C. or higher. (Appendix 8) The light-transmitting resin cover is 8. The light unit according to claim 1, wherein the temperature of the portion in contact with the side portion is equal to or lower than the continuous heat resistance temperature of the resin used. (Appendix 9) A light unit according to any one of claims 1 to 8, A fixture attached to the light unit; Equipped with lighting fixtures. [Explanation of symbols]

[0061] 10 lighting fixture, 11 fixture, 12 light unit, 20 structure, 110 mounting portion, 111 mounting spring, 112 fixture power line, 121 support, 122 LED board, 123 translucent resin cover, 124 power unit, 125 spring receiver, 126 spring insertion portion, 127 unit power line, 211 side portion, 212 plate portion, 221 LED package, 231 fitting portion, 232 end surface portion, 233 cover main portion.

Claims

1. A support body including a plate portion having an elongated shape and on which an LED substrate having a plurality of LED packages arranged in a longitudinal direction is mounted, and side portions provided on both side edges of the plate portion, which are both ends in a short direction of the plate portion; a translucent resin cover including a cover main portion covering the LED board, fitting portions provided at both ends of the cover main portion in a short direction, the fitting portions fitting with the side portions, and end surface portions closing each end of both ends of the support body in a long direction; Equipped with A light unit in which the temperature at both ends in the longitudinal direction of the support and the temperature at the sides are set to 42°C or higher when the LED package is turned on.

2. 2. The light unit according to claim 1, wherein the support has a width in a short side direction of 67 mm or less.

3. The light unit according to claim 1 or 2, wherein the support body is made of a metal.

4. 3. The light unit according to claim 1, wherein the occupancy rate of the width of the LED substrate in the short side direction relative to the width of the support in the short side direction is 38% or less.

5. 3. The light unit according to claim 1, wherein the support has a thermal conductivity in the range of 14 [W / m·K] to 300 [W / m·K].

6. 3. The light unit according to claim 1, wherein the support has a thermal conductivity of 50 [W / m·K] or more.

7. 3. The light unit according to claim 1, wherein the temperatures of both longitudinal ends and the side portions of the support are set to 48° C. or higher.

8. The light-transmitting resin cover is 3. The light unit according to claim 1, wherein the temperature of the portion in contact with the side portion is equal to or lower than the continuous heat resistance temperature of the resin used.

9. The light unit according to claim 1 or 2, A fixture attached to the light unit; Equipped with lighting fixtures.

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