JP2020184428A - Led illuminating device - Google Patents

Abstract

To provide an LED illuminating device that can prevent luminance unevenness from occurring, and can secure illuminance.SOLUTION: An LED illuminating device 1 is provided with a first LED line 30A1 formed by arranging a plurality of LED elements 30 in an oblique direction intersecting with a long-length direction L of a device body 2, and a second LED line 30A2 arranged separately from the first LED line 30A1, and formed by arranging the plurality of LED elements 30 in the oblique direction intersecting with the long-length direction L. LED elements 30 of the second LED line 30A2 are arranged at positions corresponding to positions between the respective adjacent LED elements 30 of the first LED line 30A1 when viewed from a short-length direction S of the device body 2.SELECTED DRAWING: Figure 9

Description

The present invention relates to an LED lighting device capable of preventing the occurrence of uneven brightness and ensuring illuminance.

An LED (Light Emitting Diode) lighting device is configured by arranging a plurality of LEDs at predetermined intervals on a substrate extending in the longitudinal direction inside a lighting tube, for example, as shown in Japanese Patent Application Laid-Open No. 2011-233400. (See paragraphs [0025] to [0026] of the same publication and FIGS. 1 and 2). When such an LED lighting device is lit, light is emitted from each LED, and the irradiated surface is illuminated by these emitted lights.

On the other hand, at the processing site of machine tools, lighting with fluorescent lamps has been the mainstream until now, but recently LED lighting devices have been used. At the machining site of a machine tool, the workpiece (workpiece) to be machined is cut, ground, drilled, etc. using a cutting tool (bite, etc.), which is a machining tool. It is necessary to prevent shadows and uneven brightness (illumination unevenness) due to illumination on the surface and the cutting edge portion in particular.

However, in the LED lighting device described in Japanese Patent Application Laid-Open No. 2011-233400, LEDs, which are point light sources, are arranged at intervals. Therefore, if this is used as it is for lighting a machine tool, it will process a workpiece. Light and dark lines may be generated on the surface, which may interfere with processing.

Therefore, in the LED lighting device described in Japanese Patent Application Laid-Open No. 2017-21934, at least three LED rows in which a plurality of LEDs are arranged in the longitudinal direction of the device are arranged in the lateral direction of the device, and each LED row is arranged. The devices are arranged with a slight shift in the longitudinal direction (see paragraph [0042] and FIG. 2 of the same publication), and in the same publication, the emission lines from each LED are eliminated by superimposing the emitted light from each LED. It is stated that it can be done (see paragraphs [0034] to [0035]).

In the LED lighting device described in Japanese Patent Application Laid-Open No. 2017-21934, the LEDs constituting the three rows of LED rows are arranged so as to be offset from each other when viewed from the lateral side of the device (FIG. of the same publication). 2), as shown in FIG. 5 of the same publication, when the LED lighting device is arranged sideways with respect to the spindle direction of the machine tool, it is considered that the effect as described in the same publication can be obtained. ..

However, the LEDs that make up each of the three rows of LEDs are not offset when viewed from the longitudinal direction of the device (see Fig. 2 of the same publication). Therefore, the LED lighting device is oriented vertically with respect to the spindle direction of the machine tool. When arranged, bright lines are generated by each LED in each row on the work surface of the work piece, resulting in uneven brightness. Therefore, in the one described in the same publication, the orientation in which the LED lighting device is attached is limited, and the degree of freedom in the attachment orientation is low.

The present invention has been made in view of such conventional circumstances, and an object to be solved by the present invention is to provide an LED lighting device capable of preventing the occurrence of uneven brightness. Further, the present invention aims to provide an LED lighting device having a high degree of freedom in the orientation of mounting the LED lighting device.

The LED lighting device according to the first invention of the present invention is separated from the device main body, a first LED row formed by arranging a plurality of LEDs in a direction intersecting the center line of the device main body, and the first LED row. It has a second LED row that is arranged and has a plurality of LEDs arranged in a direction intersecting the center line, and the LEDs in the second LED row are located between adjacent LEDs in the first LED row. It is located at the position corresponding to.

In the first invention of the present invention, the LEDs constituting the separated first and second LED rows are all arranged in the direction intersecting the center line of the main body of the apparatus, and the second LED row Since the LEDs of the first LED row are arranged at positions corresponding to the positions between the adjacent LEDs in the first LED row, it is the case when viewed from either the center line direction of the main body of the device or the direction orthogonal to the center line direction. However, the LEDs in the first and second LED rows can be arranged so as to be offset from each other, whereby uneven brightness occurs without causing bright lines due to each LED when viewed from any direction. It becomes possible to secure a desired illuminance on the irradiation surface. Therefore, according to the present invention, with respect to the mounting direction of the LED lighting device, whether the center line of the device main body is arranged horizontally or vertically with respect to the irradiation surface. Since it is possible to prevent uneven brightness due to each LED of the LED lighting device, it is possible to improve the degree of freedom in the mounting orientation of the LED lighting device.

The LED lighting device according to the second aspect of the present invention is separated from the device main body, a first LED row formed by arranging a plurality of LEDs in a direction intersecting the longitudinal direction of the device main body, and the first LED row. A second LED row is provided by arranging a plurality of LEDs arranged in a direction intersecting the longitudinal direction, and the LEDs in the second LED row are at least in the lateral direction, the longitudinal direction, or the separation direction of the device body. It is not aligned with the LEDs in the first LED row when viewed from either side.

In the second invention of the present invention, the LEDs constituting the separated first and second LED rows are arranged in a direction intersecting the longitudinal direction of the main body of the apparatus, and the second LED row is arranged. Since the LEDs of the device body are not aligned with the LEDs of the first LED row when viewed from at least one of the lateral direction, the longitudinal direction, and the separation direction of the device body, either the minor direction, the longitudinal direction, or the separation direction. The LEDs in the first and second LED rows can be arranged so as to be offset from each other when viewed from two directions, and as a result, the occurrence of brightness unevenness can be prevented without causing bright lines due to the LEDs, and irradiation can be performed. It becomes possible to secure a desired illuminance on the surface. Therefore, according to the present invention, with respect to the mounting direction of the LED lighting device, whether the longitudinal direction of the device main body is arranged horizontally or vertically with respect to the irradiation surface. Alternatively, even if they are arranged diagonally, it is possible to prevent uneven brightness due to each LED of the LED lighting device, so that the degree of freedom in the mounting direction of the LED lighting device can be improved.

In the present invention, the LEDs in the second LED row partially overlap the LEDs in the first LED row when viewed from at least one of the lateral direction, the longitudinal direction, and the separation direction. As a result, it is possible to reliably prevent the generation of bright lines by each LED.

In the present invention, a plurality of LED arrays composed of first and second LED rows are provided. According to the present invention, if a plurality of such LED arrays are provided in the device body, for example, in the longitudinal direction, it is possible to prevent the occurrence of luminance unevenness over the entire length direction of the device body, and to obtain a desired illuminance on the irradiation surface. Can be secured. Further, if a plurality of the LED arrays are provided in the device main body, for example, in the lateral direction, it is possible to more reliably prevent the occurrence of luminance unevenness over the entire device body in the lateral direction.

In the present invention, the LED array includes a first LED array and a second LED array that is separated from the first LED array, and the first LED array of the second LED array. And the second LED row of the first LED array are aligned in the array direction. According to the present invention, the LED arrangement is the first LED arrangement of the first LED arrangement, the second LED arrangement of the first LED arrangement, and the first LED arrangement of the second LED arrangement. The arrangement pattern can be simplified by being composed of three LED arrangements called the second LED arrangement of the two LED arrangements.

In the present invention, a plurality of lenses for condensing the light emitted from each LED are further provided, and the adjacent lenses of the plurality of lenses are partially overlapped with each other. As a result, the emitted light from each LED can be emitted to the outside through the overlapping portion of each lens, so that it is possible to prevent the lens emitting surface from becoming relatively dark at the boundary region of each lens, and the lens emitting surface can be prevented from becoming relatively dark. The overall brightness difference can be reduced. On the other hand, when the lenses are arranged apart from each other, an event occurs in which the light emitted from the LED cannot be emitted to the outside in the boundary region of the adjacent lenses, and as a result, the light emitting surfaces of the lenses are affected by each. It becomes relatively dark in the boundary region of the lens, and the difference in brightness of the entire lens light emitting surface becomes large.

In the present invention, a reflecting portion is provided that reflects the light collected by the plurality of lenses toward the outside of the device. As a result, it is possible to more reliably prevent irradiation unevenness from occurring on the irradiation surface.

As described above, according to the present invention, each of the LEDs constituting the separated first and second LED rows is arranged in a direction intersecting the center line (or longitudinal direction) of the main body of the apparatus, and the first and second LEDs are arranged. The LEDs of the second LED row are arranged at positions corresponding to the positions between the adjacent LEDs of the first LED row (or viewed from at least one of the lateral direction, the longitudinal direction, and the separation direction of the device body). Since it is not aligned with the LEDs in the first LED row), when viewed from the center line direction of the main body of the device and the direction orthogonal to this (or either the lateral direction, the longitudinal direction, or the separation direction). (When viewed from the above), the LEDs in the first and second LED rows can be arranged so as to be offset from each other, whereby the occurrence of brightness unevenness can be prevented without causing bright lines due to each LED, and irradiation can be performed. It becomes possible to secure the desired illuminance on the surface. Further, regarding the mounting direction of the LED lighting device, the center line of the device body may be arranged horizontally or vertically (or diagonally) with respect to the irradiation surface. However, since it is possible to prevent uneven brightness due to each LED of the LED lighting device, it is possible to improve the degree of freedom in the orientation of mounting the LED lighting device.

It is an overall perspective view of the LED lighting apparatus according to one Example of this invention. It is a top view of the LED lighting device (FIG. 1). FIG. 3 is a schematic cross-sectional view taken along line III-III of the LED lighting device (FIG. 2). FIG. 3 is a plan view of the lens constituting the LED lighting device (FIG. 3) viewed from diagonally above. It is a front view which looked at the lens (FIG. 4) from diagonally above. It is a bottom view which looked at the lens (FIG. 4) from diagonally below. It is a bottom view of the lens (FIG. 4). It is a top view of the LED substrate which comprises the LED lighting apparatus (FIG. 2), and is the figure which shows the LED arrangement. It is a figure for demonstrating the LED arrangement (FIG. 8). It is a figure for demonstrating the LED arrangement (FIG. 8). It is a figure corresponding to the XI-XI line cross section of FIG. 8 in the LED lighting apparatus (FIG. 2). It is a figure corresponding to the XII-XII line cross section of FIG. 8 in the LED lighting apparatus (FIG. 2). It is a figure corresponding to the XIII-XIII line cross section of FIG. 8 in the LED lighting apparatus (FIG. 2). It is a figure for demonstrating the luminance distribution of the LED lighting apparatus (FIG. 2), (a) corresponds to FIG. 2, (b) is the luminance distribution diagram of the LED lighting apparatus (a), (a). c) is a graph showing the brightness distribution of (b) using the brightness value on the vertical axis, and (d) is a diagram showing the state of the irradiation surface irradiated with the light emitted from the LED lighting device of (a). .. It is an enlarged view of FIG. 14 (c). It is a figure for demonstrating the luminance distribution of the conventional LED lighting apparatus, and corresponds to FIG. 14, (a) is a plan view of the LED lighting apparatus, (b) is the luminance of the LED lighting apparatus of (a). The distribution diagram, (c) is a graph showing the brightness distribution of (b) using the brightness value on the vertical axis, and (d) shows the state of the irradiation surface irradiated with the light emitted from the LED lighting device of (a). It is a figure which shows.

Hereinafter, examples of the present invention will be described with reference to the accompanying drawings.
1 to 15 are diagrams for explaining an LED lighting device according to an embodiment of the present invention. Here, an LED lighting device used at a machine tool processing site is taken as an example. In the following description, for convenience of explanation, the upper side (upper, upper) refers to the light emitting surface side of the LED lighting device, and the lower side (lower, lower) is opposite to the light emitting surface of the LED lighting device. I will point to the side. That is, for example, in FIG. 2, the upper side (upper, upper) refers to the front side of the drawing, and the lower side (lower, lower) refers to the back side of the drawing. Further, the longitudinal direction of the main body of the apparatus refers to the left-right direction of FIG. 2, and the lateral direction refers to the vertical direction of FIG. Further, in each of the cross-sectional views of FIGS. 3, 11 to 13, the cross-sectional area is indicated by black dots.

As shown in FIGS. 1 and 2, the LED lighting device 1 has, for example, a metal case (device body) 2 extending in the longitudinal direction, and a plurality of LED (Light Emitting Diode) elements (light Emitting Diode) elements inside the case 2. A substrate 3 on which (not shown) is mounted is housed. In this example, the case 2 is a member having a rectangular shape in a plan view. A window hole 2a is formed through the case 2 on the light emitting surface side, and a transparent (or translucent) plate-shaped glass or resin window portion 4 is attached to the window hole 2a. There is. Further, a power cable 5 for supplying a power supply current to an internal device is connected to one end of the case 2.

FIG. 3 shows a cross section taken along line III-III of FIG. 2, but the case 2 and the window portion 4 are not shown. As shown in FIG. 3, the LED element 30 is arranged on the substrate 3. A lens 6 made of, for example, a transparent resin is arranged above the LED element 30. The lens 6 is a member for irradiating the outside of the device while reflecting and condensing the light emitted from the LED element 30. The lens 6 has a plate-shaped flat surface portion 60 arranged on the upper side (that is, immediately below the window portion 4) and a plurality of convex shapes extending downward from the lower surface of the flat surface portion 60 and integrally formed with the flat surface portion 60. It has a part 61. The lens 6 is held from below by a reflector (reflecting portion) 7 that abuts on the flat surface portion 60 from below. The reflector 7 is formed with a recess for accommodating the flat surface portion 60, and the standing wall portion 7a of the recess is colored, for example, white, whereby the standing wall portion 7a is focused by the convex portion 61. Irradiation unevenness is prevented by reflecting the light toward the outside of the device.

As shown in FIGS. 4 and 5, a microlens array in which a large number of micromicrolenses 60a are arranged in a honeycomb shape in a plane is provided on the upper surface of the flat surface portion 60. Each microlens 60a has a convex arcuate surface on the upper surface. As shown in FIGS. 3, 5 to 7, each convex portion 61 bulges downward from the lower surface of the flat surface portion 60, respectively, and the outer diameter gradually increases toward the lower tip side. It's getting smaller. A hole 61a is formed on the lower surface of each convex portion 61. The convex portion 61 is provided in a one-to-one correspondence with the LED element 30, and the corresponding LED element 30 is arranged below the hole 61a of the convex portion 61. In this example, one lens 6 is provided with 6 × 2 rows, that is, 12 convex portions 60. As shown in FIG. 7, each convex portion 60 is provided so as to partially overlap each convex portion 60 adjacent thereto. That is, in the figure, the convex portion 61A partially overlaps with the surrounding convex portions 61B, 61C, 61D, and 61E. In FIG. 3, a cross section of the convex portion 61 corresponding to the LED element 30 and a cross section of a part of the adjacent convex portion 61 overlapping the cross section of the convex portion 61 are shown.

In this embodiment, as shown in FIG. 2, five lenses 6 are arranged side by side along the longitudinal direction of the apparatus main body 2. Further, in the figure, a state in which each convex portion 61 of the lens 6 is seen through the window portion 4 and the flat surface portion 60 is shown.

Next, the LED arrangement according to this embodiment will be described with reference to FIG.
FIG. 8 shows a state in which only the LED element 30 is arranged on the substrate 3 extending in the longitudinal direction. In the figure, the arrow L indicates the longitudinal direction of the apparatus main body 2 of FIG. 2, and the arrow S indicates the lateral direction of the apparatus main body 2. As shown in the figure, in the LED array 30A arranged on the left end side of the substrate 3 in the drawing, a plurality of (6 in this example) LED elements 30 are arranged obliquely with respect to the longitudinal direction L at predetermined intervals. The first LED row 30A ₁ and the first LED row 30A _{1 are} separated from each other, and similarly, a plurality of (six in this example) LED elements 30 are arranged at predetermined intervals with respect to the longitudinal direction L. It is composed of a _second LED row 30A _{2 which} is diagonally arranged. Further, on the right side of the LED array 30A on the substrate 3, LED arrays 30B, 30C, 30D, and 30E having the same configuration as the LED array 30A are arranged. Notches 3c are formed at a plurality of locations on the outer peripheral surface of the substrate 3 with which mounting screws (not shown) for fixing the substrate 3 to the mounting surface in the case 2 (FIG. 2) are engaged. ..

The details of the LED array 30A of FIG. 8 will be described with reference to FIG.
FIG. 9 shows a state in which the LED array 30A is arranged sideways. As shown in the figure, the angle (that is, the inclination angle) formed by the center line of the first LED row 30A ₁ (that is, the line passing through the center of each LED element 30) CA ₁ counterclockwise with respect to the longitudinal direction L is set. If α,
0 <α <90 °, preferably 0 <α <45 °
Is. The size of the angle α is appropriately set according to the length in the longitudinal direction, the length in the lateral direction, the number and spacing of the LED elements 30 to be arranged, and the like.

Similarly, assuming that the angle (that is, the inclination angle) formed by the center line of the second LED row 30A ₂ (that is, the line passing through the center of each LED element 30) CA ₂ counterclockwise with respect to the longitudinal direction L is α'. ,
0 <α'<90 °, preferably 0 <α'<45 °
Is. The size of the angle α'is appropriately set according to the length in the longitudinal direction, the length in the lateral direction, the number and spacing of the LED elements 30 to be arranged, and the like.
In this example, α = α'. Therefore, the first and second LED rows 30A ₁ and 30A ₂ are arranged in parallel with each other.

As shown in FIG. 9, each LED element 30 constituting the first LED string 30A ₁ and the LED elements _{30 1,} 30 _{2, 30} 3, 30 _4, 30 5, 30 _6, one side _{a 1} they both to have a plan view a square shape, and the longitudinal spacing between the opposite sides of the LED elements adjacent in the longitudinal direction L and e, the short-side direction of the center line of each LED element and c ₁ To do. Similarly, the LED elements 30 constituting the second LED string 30A ₂ LED element 30 ₁ ', 30 _2', 30 ₃ ', 30 _4', 30 ₅ ', 30 _6' and either of which is one side and has in plan view a square shape of a _2, the longitudinal distance between the opposite sides of the LED elements adjacent in the longitudinal direction L and e ', the lateral direction of the center line of the LED elements Let it be c ₂ . In this example, e = e'. Therefore, the LED elements 30 of the first and second LED rows 30A ₁ and 30A ₂ are all arranged at equal intervals (equal pitch) in the longitudinal direction. Further, in this example, a ₁ = a ₂ , and all the LED elements 30 have the same size.

In this case, each center line _{c 2} of the second LED elements 30 of the LED string 30A ₂ is the distance e (more specifically the distance e between the first LED elements 30 adjacent LED strings 30A ₁ It passes through the midpoint). Similarly, each center line _{c 1} of the first LED elements 30 of the LED string 30A _1, the distance e '(more specifically the distance e between the second LED string 30A LED elements 30 neighboring ₂ It passes through the'midpoint). Therefore, in this example, it can be said that each LED element 30 of the second LED row 30A ₂ is arranged at a position corresponding to the position between the adjacent LED elements 30 of the first LED row 30A ₁ . In this case, each LED element 30 of the second LED row 30A ₂ is arranged so as to be offset from each corresponding LED element 30 of the first LED row 30A ₁ .

In other words, each LED element 30 of the second LED row 30A ₂ is not aligned with each LED element 30 of the _first LED row 30A _{1 when} viewed from the lateral direction S. Similarly, each LED element 30 of the first LED row 30A ₁ is not aligned with each LED element 30 of the _second LED row 30A _{2 when} viewed from the lateral direction S. Here, the state in which both LED elements 30 are aligned means a state in which the center lines c ₁ and c _{2 of} the corresponding LED elements 30 are completely aligned when viewed from the lateral direction S.

In this example, when projecting the side _{a 1} in the transverse direction of the first LED elements 30 of the LED string 30A ₁ in the lateral direction (see dotted line in FIG. 9), the second LED string 30A ₂ overlapping the sides _{a 2} in the lateral direction of the LED elements 30. Similarly, when projecting the lateral direction of the side _{a 2} of the second LED elements 30 of the LED string 30A ₂ in the lateral direction (see dotted line in the drawing), the first of each LED element of the LED string 30A ₁ It overlaps with the side _{a 1} in the lateral direction 30. Therefore, it can be said that each LED element 30 of the second LED row 30A ₂ partially overlaps with each LED element 30 of the first LED row 30A _{1 when} viewed from the short side. In FIG. 9, the distance d between the center line _{c 2} of the second LED elements 30 of the LED string 30A ₂ with the center line _{c 1} of the first LED element 30 of the LED string 30A ₁ is
_{d = a 2/2 + a} 1/2 = a 1/2 + a 1/2 = a 1 = a 2 [∵a 1 = a 2]
Is.

Next, FIG. 10 shows a state in which the LED array 30A of FIG. 9 is arranged vertically.
In FIG. 10, the same reference numerals as those in FIG. 9 indicate the same parts. As shown in FIG. 10, the center line CA ₂ of the first LED string 30A ₁ of the center line CA ₁ and the second LED string 30A ₂ is disposed to be inclined relative to the longitudinal direction L, the first , The second LED rows 30A ₁ and 30A ₂ are arranged parallel to each other.

As shown in FIG. 10, the LED elements ₃₀ 1 constituting the first LED string _{30A 1, 30 2, 30 3} , 30 4, 30 5, 30 6 , each have a square in plan view shape of the one side _{a 1} and have, likewise, the LED elements 30 ₁ constitutes the second LED string _{30A 2 ', 30 2',} 30 3 ', 30 4', 30 5 ', 30 6' are each side _a 2 ( = A It has a square shape in a plan view of ₁ ). The LED elements 30 of the first and second LED rows 30A ₁ and 30A ₂ are all arranged at equal intervals (equal pitch) in the longitudinal direction.

At this time, when projecting the one side _{a 1} in the longitudinal direction of the first LED element 30 of the LED string 30A ₁ in the longitudinal direction (see a dotted line in FIG. 10), the LED element 30 and the longitudinally adjacent LED elements Pass through 30. That is, when projecting the side _{a 1} of the right side of the LED element 30 ₆ in the longitudinal direction through the approximate center of the LED elements 30 _5, when projecting the side _{a 1} of the right side of the LED element 30 ₅ in the longitudinal direction, the LED elements 30 ₄ passes through the approximate center of the projecting edges _{a 1} of the right side of the LED element 30 ₄ in the longitudinal direction through the approximate center of the LED element 30 _3, in the same manner, the LED elements 30 illustrated _second right side When a ₁ is projected in the longitudinal direction, it passes through the substantially center of the LED element 30 ₁ . Therefore, the LED elements 30 of the first LED row 30A ₁ overlap in the longitudinal direction.

On the other hand, when projecting the longitudinal one side _{a 1} of the LED elements 30 of the second LED string 30A ₂ in the longitudinal direction (see a dotted line in FIG. 10), LED elements 30 adjacent to the LED element 30 and the longitudinal direction Passes through the center of. That is, 'when projecting the side _{a 1} of the right side of the longitudinal direction, the LED elements 30 _5' LED element 30 ₆ passes through the approximate center of the projecting edges _{a 1} of the right side of the LED element 30 ₅ 'in the longitudinal direction , 'through the approximate center of, the LED elements 30 _4' LED element 30 ₄ projecting edges _{a 1} of the right side of the longitudinal direction through the approximate center of the LED element 30 ₃ ', in the same manner, the LED elements 30 'When the side _{a 1} of the right side of the projection in the longitudinal direction, LED element 30 _{1' 2} passing through the approximate center of the. Therefore, the LED elements 30 of the second LED row 30A ₂ overlap in the longitudinal direction.

Also, when projecting the side _{a 1} of the left side of the second LED element 30 ₆ LED strings 30A ₂ 'in the longitudinal direction through the first LED element 30 _{and second} LED arrays 30A _1, second LED string 30A When the side _{a 1} of the left side of the _second LED element 30 ₅ 'projects longitudinally through the LED element 30 ₁ of the first LED string 30A _1. Therefore, each LED element 30 of the second LED row 30A ₂ partially overlaps with each LED element 30 of the first LED row 30A _{1 when} viewed from the longitudinal direction L. In other words, each LED element 30 of the second LED row 30A ₂ is not aligned with each LED element 30 of the _first LED row 30A _{1 when} viewed from the longitudinal direction L. Similarly, each LED element 30 of the first LED row 30A ₁ is not aligned with each LED element 30 of the _second LED row 30A _{2 when} viewed from the longitudinal direction L. Here, the state in which both LED elements 30 are aligned means a state in which the center lines in the longitudinal direction of the corresponding LED elements 30 are completely aligned when viewed from the longitudinal direction L.

As described above, FIG. 8 shows a state in which the LED arrays 30B, 30C, 30D, and 30E having the same configuration as the LED array 30A are arranged in order on the right side of the LED array 30A. At this time, the center line CB ₁ of each LED element 30 of the first LED row 30B ₁ of the LED array 30B is the center line of each LED element 30 of the second LED row 30A ₂ of the LED array 30A. It coincides with CA ₂ and both center lines are arranged on the same straight line. The same applies to the other LED arrays 30B, 30C, 30D, and 30E. For example, the center line of each LED element 30 of the first LED row 30D ₁ of the LED array 30D is the second of the LED array 30C. It coincides with the center line of each LED element 30 of the LED row 30C ₂ and both center lines are arranged on the same straight line.

Therefore, the LED arrangement shown in FIG. 8 is a first LED row 30A ₁ composed of six LED elements 30 in the LED array 30A and a second LED row consisting of six LED elements 30 in the LED array 30A. Three LED arrangements: a _first LED row 30B ₁ consisting of six LED elements 30 in the 30A ₂ and the LED array 30B, and a second LED row 30B ₂ consisting of six LED elements 30 in the LED array 30B. It can be said that the LED elements 30 are composed of 6, 12, and 6 LED elements. In the LED arrangement pattern in the LED lighting device of this embodiment, such three LED arrangements are repeated in the longitudinal direction of the device body. As a result, the arrangement pattern can be simplified, so that the manufacturability (easiness of manufacturing) and the assembling property (easiness of assembling) can be improved.

Further, in the example shown in FIG. 8, the rearmost LED element 30 in the second LED row 30A ₂ of the LED array 30A and the first LED element 30 in the first LED row 30B ₁ of the LED array 30B The spacing between the LEDs is slightly wider than the spacing (pitch) of each LED element 30 due to manufacturing reasons (the same applies to other LED arrays), but even in that case, the LED array 30B is the first. Since the first LED element 30 in the LED row 30B ₂ of ₂ partially overlaps the last LED element 30 in the first LED row 30A ₁ of the LED array 30A, there is no practical problem. The interval may be equal to the interval of each LED element 30.

Next, the XI-XI line cross section, the XII-XII line cross section, and the XIII-XIII line cross section of FIG. 8 are shown in FIGS. 11, 12, and 13, respectively. In FIG. 8, only the substrate 3 and the LED element 30 are shown, but in the cross-sectional views of FIGS. 11 to 13, in addition to these, internal parts including the lens 6 and the reflector 7 are also shown. That is, FIGS. 11 to 13 correspond to a cross-sectional view in which the case 2 and the window portion 4 are omitted from the device main body 2 of the LED lighting device 1. Therefore, FIG. 3, which is a similar cross-sectional view, corresponds to the cross section taken along line III-III in FIG. As shown in FIGS. 11 to 13, the convex portion 61 of the lens 6 partially overlaps with the convex portion 61 of the lens 6 adjacent thereto in any of the cross sections.

Next, the action and effect of this example will be described with reference to FIGS. 14 and 15.
14 (a) is a plan view of the LED lighting device according to the present embodiment, (b) is a brightness distribution diagram of the LED lighting device, and (c) is a brightness distribution of (b) shown by using brightness values on the vertical axis. The graph (d) is a diagram showing the state of the irradiation surface irradiated with the light emitted from the LED lighting device, and FIG. 15 is an enlarged view of FIG. 14 (c). In FIG. 14D, the LED lighting device is arranged sideways with respect to the irradiation surface.

Graphs 1, 2 and 3 in FIGS. 14 (c) and 15 correspond to LED rows 1, 2 and 3 in FIG. 14 (b), respectively. That is, showing the correspondence with the LED rows in FIG. 8, graph 1 corresponds to the _first LED row 30A ₁ of the LED array 30A, and graph 2 shows the second LED row 30B of the LED array 30B. ₂ and the first LED row 30C ₁ of the LED array 30C, graph 3 corresponds to the second LED row 30A ₂ of the LED array 30A and the first LED row 30B ₁ of the LED array 30B. ing.

As shown in FIG. 15, the upper limit Imax and the lower limit Imin of the brightness values in each of the LED rows 30A ₁ , 30A ₂ , 30B ₁ , 30B ₂ , and 30C ₁ generally exist in the region D in the same figure. Focusing on Graph 1 located on the left side of the figure, Graph 1 repeats peaks (upper limit) and valleys (lower limit) in the range of region D, but the adjacent peaks and peaks in Graph 1 The peaks in Graph 3 are located between (that is, the positions of the valleys). Note that Graph 3 also repeats peaks and valleys, but the peaks in Graph 1 are located between adjacent peaks in Graph 3. Focusing on Graph 2 located in the center of the figure, Graph 2 repeats peaks and valleys within the range of region D, but the peaks in Graph 3 are between adjacent peaks in Graph 2. Is located. The mountain of Graph 2 is located between the adjacent mountains of Graph 3. The position of the peak in each graph corresponds to the position of the LED element of each LED row, and the position of the valley is the position between the adjacent LED elements in each LED row (that is, the position where the LED element is not arranged). ) Is supported.

As shown in FIG. 14D, as for the state of the irradiation surface, the entire irradiation surface irradiated by the LED lighting device is brightly illuminated, and no bright and dark lines are generated. That is, no bright line is generated by each LED element in each LED row, and no uneven brightness is generated. Therefore, the desired illuminance is secured on the irradiation surface.

This is because, as described above, the LED elements of the LED row adjacent to the LED row in the lateral direction are arranged (that is, both LEDs) corresponding to the positions where the LED elements are not arranged in the LED row. This is because the corresponding LED elements in the row are staggered), which causes the emitted light from each LED element in both LED rows to overlap, resulting in a smaller difference in brightness for the entire device. , The irradiated surface (processed surface of the workpiece of the machine tool) is uniformly brightly illuminated. Further, in this embodiment, as shown in FIG. 13, the adjacent convex portions 61 of the lens 6 are overlapped with each other, so that the light emitted from the LED element 30 is L, as shown by the alternate long and short dash line in the figure. ₀ 'and the outgoing light _{L 0} from the' LED element 30 and is transmitted through the overlapping portions of the respective convex portions 61, between so that each outgoing light _L 0, _{L 0} 'is, the LED elements 30 and 30' In combination with this, the brightness at the position where the LED element is not arranged is increased. Therefore, the lower limit Imin of the brightness in FIG. 15 is not I ₀ (= 0).

FIG. 14D shows an example in which the LED lighting device is arranged sideways with respect to the irradiation surface (that is, in a machine tool lathe, the short side direction of the LED lighting device is arranged in a vertical cross section passing through the work center line. ) Is shown, but in this embodiment, when the LED lighting device is arranged vertically with respect to the irradiation surface (that is, in a machine tool lathe, a vertical cross section that passes through the work center line in the longitudinal direction of the LED lighting device). Even when it is arranged inside), the same effect as in the case of the horizontal arrangement can be obtained. That is, the entire irradiated surface irradiated by the LED lighting device is brightly illuminated, no bright and dark lines or bright lines are generated, and no uneven brightness is generated. This ensures the desired illuminance on the irradiated surface. This is because, as described with reference to FIG. 10, each LED element in the LED row partially overlaps in the longitudinal direction, and therefore the emitted light from each LED element is superimposed.

As described above, in the LED lighting device according to the present embodiment, even if the LED lighting device is mounted horizontally or vertically with respect to the irradiation surface, it is possible to prevent uneven brightness due to each LED. The degree of freedom in the mounting orientation of the lighting device can be improved.

Here, as a comparative example of this embodiment, the brightness distribution of the conventional LED lighting device is shown in FIG. FIG. (A) is a plan view of a conventional LED lighting device, (b) is a brightness distribution diagram of an LED lighting device, and (c) is a graph showing the brightness distribution of (b) on the vertical axis using brightness values. FIG. 1D is a diagram showing a state of an irradiation surface irradiated with light emitted from an LED lighting device. In FIG. 16D, the LED lighting device is arranged sideways with respect to the irradiation surface.

In a conventional LED lighting device, as shown in FIG. 16A, a plurality of LED elements are arranged in a row at intervals. As shown in FIG. 3C, the brightness value of the single row LED row repeats peaks (upper limit value) and valleys (lower limit value), and the upper limit Imax and lower limit Imin are approximately the region D in the figure. It exists in', but in this case, Imin = I ₀ = 0. The position of the peak in the graph corresponds to the position of each LED element in the LED row, and the position of the valley is the position between each adjacent LED element in the LED row (that is, the position where the LED element is not arranged). It corresponds.

As shown in FIG. 16D, the irradiation surface irradiated by the LED lighting device has bright and dark lines. That is, bright lines are generated by each LED element in the LED row, and uneven brightness (illumination unevenness) occurs. In such a state of uneven lighting, if it is used as lighting for a machine tool, bright and dark lines will be generated on the machined surface of the workpiece, which may hinder the actual machining.

[First modification]
In the above embodiment, the case where the device main body 2 of the LED lighting device 1 is a member having a rectangular shape in a plan view extending in the longitudinal direction has been described as an example, but the application of the present invention is not limited to this. The device main body 2 may be a member having a square shape in a plan view or a regular polygon shape in a plan view without a longitudinal direction and a lateral direction. In these cases, a center line may be defined instead of the longitudinal direction in the embodiment, and each LED row may be arranged so as to intersect the center line diagonally.

[Second modification]
In the above embodiment, the corresponding LED elements 30 in the first and second LED rows constituting each LED array are arranged so as to be offset from each other when viewed from both the lateral direction and the longitudinal direction of the apparatus main body 2. However, the application of the present invention is not limited to this.

When the mounting direction of the LED lighting device is fixed with respect to the irradiation surface, each of the corresponding LED elements 30 in the first and second LED rows is either in the lateral direction or the longitudinal direction of the device main body. When viewed from one side, they may be arranged so as to be offset from each other. For example, as shown in FIG. 14D, when the LED lighting device is arranged sideways with respect to the irradiation surface, each LED element in the LED row is viewed from the short side as shown in FIG. In these cases, it is preferable that they overlap each other, but when viewed from the longitudinal direction L, they do not necessarily have to overlap as shown in FIG. On the other hand, when the LED lighting devices are arranged vertically with respect to the irradiation surface, the LED elements in the LED row overlap each other when viewed from the longitudinal direction as shown in FIG. However, when viewed from the lateral direction S, they do not necessarily have to overlap as shown in FIG.

[Third variant]
In the LED arrangement in the above embodiment, as shown by the arrow N of the one-point chain line in FIG. 9, each LED element 30 of the first LED row 30A ₁ is moved by a predetermined distance in the N direction (separation direction). It can also be considered that the LED row 30A _{2 of 2} is configured. In this case, when viewed from the N direction, the corresponding LED elements 30 of the first and second LED rows 30A ₁ and 30A ₂ completely overlap each other, but even in that case, when viewed from the N direction. The area where the LED element 30 is not arranged is narrow, and uneven brightness is unlikely to occur. Therefore, when installing the LED lighting device, even if the N direction is arranged in the vertical cross section passing through the work center line of the lathe of the machine tool, bright and dark lines and bright lines do not occur on the irradiation surface, and uneven brightness does not occur. .. If the inclination changes even slightly from the N direction, the corresponding LED elements 30 of the first and second LED rows 30A ₁ and 30A ₂ will partially overlap, so that the brightness unevenness on the irradiation surface will occur. The occurrence can be prevented more reliably.

As described above, the mounting direction of the LED lighting device is not limited to the horizontal orientation and the vertical orientation, and can be arranged diagonally between the horizontal orientation and the vertical orientation, so that the degree of freedom in the mounting orientation can be further improved. Further, when the mounting direction of the LED lighting device is fixed obliquely with respect to the irradiation surface, the corresponding LED elements 30 in the first and second LED rows are viewed from the diagonal direction of the device main body. They may be arranged so as to be offset from each other, and may not be arranged so as to be displaced from each other when viewed from the lateral direction or the longitudinal direction of the device main body.

[Fourth variant]
In the above embodiment, the tilt angle α'of the _second LED row 30A ₂ is equal to the tilt angle α of the first LED row 30A ₁ (α = α'), and the first and second LED rows 30A ₁ , 30A. _Although the example in which ₂ is arranged parallel to each other is shown, the application of this invention is not limited to this. It may be α <α'or α>α'. That is, the center lines CA1 and CA2 of the first and second LED rows 30A ₁ and 30A ₂ do not necessarily have to be strictly parallel lines.

[Fifth variant]
In the above-described embodiment, the first and second LED rows 30A ₁ and 30A ₂ are arranged in parallel with each other, but the application of the present invention is not limited to this. The first LED row 30A ₁ and the second LED row 30A ₂ may be arranged so as to intersect in a horizontal V shape. Then, a plurality of such V-shaped LED arrays may be arranged in the longitudinal direction of the main body of the apparatus, and the adjacent LED arrays may be partially overlapped.

[Sixth variant]
In the above embodiment, the LED elements 30 of the first and second LED rows 30A ₁ and 30A ₂ are all arranged at equal intervals (equal pitch) in the longitudinal direction, but the present invention is applicable. Not limited to this. The interval between the LED elements 30 may be changed depending on the row. That is, the distance between the LED elements 30 in one LED row may be wider (or narrower) than the distance between the LED elements 30 in the other LED row. Further, in the same LED row, the spacing between the LED elements 30 may be gradually reduced (or increased) along the longitudinal direction, or the spacing may be randomized.

[7th variant]
In the above embodiment, the case where the size of each LED element 30 of the second LED row 30A ₂ is the same as the size of each LED element 30 of the first LED row 30A ₁ has been described as an example, but each LED element has been described. The size of 30 may vary depending on the row and the LED element 30.

[8th variant]
In the above embodiment, the example in which the LED array is composed of two LED rows, that is, the first and second LED rows, is shown, but the LED array according to the present invention is composed of three or more LED rows. You may.
You may.

[9th variant]
In the above embodiment, the first and second LED rows 30A ₁ and 30A ₂ are all composed of 6 LED elements 30, but the number of LED elements is more than 6 or less. May be good.

[Other variants]
The above-mentioned examples and each modification should be regarded in all respects merely as an example of the present invention, and are not limited. Those skilled in the art in the field to which the present invention is related will not deviate from the spirit and essential features of the present invention when considering the above teaching contents, even if not explicitly stated in the present specification. Various variants and other embodiments that employ the principle of can be constructed.

[Other application examples]
The application of the present invention is not limited to the above-mentioned lighting device for machine tools, but the present invention requires an assembly / repair site of precision equipment (for example, a mechanical clock) that requires detailed work, and a precise touch. It can also be applied to lighting equipment in production workshops such as arts and crafts.

The present invention is useful for an LED lighting device for preventing the occurrence of uneven brightness and ensuring illuminance.

1: LED lighting device

30: LED element 30A: (1st) LED array 30A ₁ : 1st LED row 30A ₂ : 2nd LED row 30B: (2nd) LED array 30B ₁ : 1st LED row 30B ₂ : 2nd LED row

6: Lens

7: Reflector (reflector)

L: Longitudinal direction S: Short direction

Japanese Unexamined Patent Publication No. 2011-233400 (see paragraphs [0025] to [0026] and FIGS. 1 and 2). Japanese Unexamined Patent Publication No. 2017-21934 (see paragraphs [0034] to [0035], [0042] and FIG. 2).

Claims (7)

In LED lighting equipment
With the device body
A first LED row formed by arranging a plurality of LEDs in a direction intersecting the center line of the apparatus main body,
It is provided with a second LED row which is arranged apart from the first LED row and has a plurality of LEDs arranged in a direction intersecting the center line.
The LEDs in the second LED row are arranged at positions corresponding to positions between the adjacent LEDs in the first LED row.
An LED lighting device characterized by this. In LED lighting equipment
With the device body
A first LED row formed by arranging a plurality of LEDs in a direction intersecting the longitudinal direction of the apparatus main body,
It is provided with a second LED row that is separated from the first LED row and has a plurality of LEDs arranged in a direction intersecting the longitudinal direction.
The LED in the second LED row is not aligned with the LED in the first LED row when viewed from at least one of the lateral direction, the longitudinal direction, and the separation direction of the apparatus main body.
An LED lighting device characterized by this. In claim 2,
The LEDs in the second LED row partially overlap with the LEDs in the first LED row when viewed from at least one of the lateral direction, the longitudinal direction, and the separation direction. Yes,
An LED lighting device characterized by this. In claim 1 or 2,
A plurality of LED arrays composed of the first and second LED rows are provided.
An LED lighting device characterized by this. In claim 4,
The LED array includes a first LED array and a second LED array that is separated from the first LED array.
The first LED row of the second LED array and the second LED row of the first LED array are aligned in the arrangement direction.
An LED lighting device characterized by this. In claim 1 or 2,
A plurality of lenses for collecting the light emitted from each of the LEDs are further provided.
Each of the adjacent lenses of the plurality of lenses is provided so as to partially overlap each other.
An LED lighting device characterized by this. In claim 6,
A reflecting unit is provided to reflect the light collected by the plurality of lenses toward the outside of the device.
An LED lighting device characterized by this.