JP2019009059A - Suspended lighting device - Google Patents

Abstract

To provide a suspended lighting device capable of reducing a risk of falling due to strong vibration or resonance.SOLUTION: A lighting device comprises a screw part formed at an end part of a hanging rod, and has a holding structure with a pair of nuts assembled into the screw part or a combination of a nut and a hanging rod step part. The lighting device is configured to rotate and fasten the nut assembled into the screw part to fix a lamp fixture. In a state where the lamp fixture is suspended to a building material to which the lamp fixture is attached, a nut receiving a load from gravity is provided with a whirl-stop structure configured to prevent rotation of the nut in the suspended state.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a hanging type illumination device fixed to a construction material such as a ceiling.

  2. Description of the Related Art Conventionally, a hanging illumination device includes a lamp and a hanging rod connected to the lamp, and the hanging rod is suspended from a construction material mounting surface by being fixed to a construction material such as a ceiling or a beam. (For example, refer to Patent Document 1). In Patent Document 1, a structure that is fastened and fixed with a double nut in order to prevent the rotation of the main body, and a protrusion or slit is provided on the hanging rod to combine with the lamp main body recess to more reliably suppress the rotation of the lamp main body. A structure is disclosed. The document also discloses that simply tightening with a double nut may cause the nut to gradually loosen due to vibration or wind pressure, and the instrument body to rotate. Usually, in lighting devices having a structure in which a lamp is suspended by a single hanging rod, the hanging rod is in the shape of a hollow pipe, and there are many cases in which a power supply line passes therethrough. In addition, in a long hanging lighting device such as a fluorescent lamp, a suspension rod through which a power supply line passes among a plurality of suspension rods is connected and fixed to a terminal box fixed to the construction material. The power supply line that is passed through the conduit provided on the mounting surface and the lead wire of the lamp that is passed through the suspension rod are connected, and the other suspension rods are fixed to the suspension fitting (for example, Patent Documents) 2). With this type of hanging lighting system, it is necessary to perform wiring work and lamp fixing work near the ceiling of a factory or the like, so it is desired to improve the mounting workability, and the lamp fixing work after wiring is simplified. Therefore, a technique has also been disclosed in which a U-shaped groove is provided in a mounting bracket through which a suspension bar is passed, and the suspension bar can be easily fixed by inserting the suspension bar into the groove from the side (see, for example, Patent Document 3).

Japanese Unexamined Patent Publication No. 09-027211 Utility Model No. 3008676 JP 2014-0269937 A

  By the way, the hanging type illumination device is relatively heavy and is provided at a relatively high position such as a factory ceiling. For this reason, a structure that can be easily attached is desired. In some cases, only those that have passed a severe vibration test and passed the product are put on the market as products. The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a hanging illumination device in which a hanging rod does not come off or drop even when intense vibration or vibration at a resonance frequency is applied.

  In order to achieve the above object, according to the present invention, there is provided a hanging type lighting apparatus in which a lamp is suspended and fixed to a construction material via a hanging rod, and a threaded portion is formed at an end of the hanging rod. A structure in which a pair of nuts incorporated in a portion or a combination of a nut and a stepped portion of a suspension rod is sandwiched, and a nut that receives a load due to gravity is not rotated while the lamp is suspended and fixed to the construction material It is characterized by that.

  The said structure WHEREIN: The said lamp may be suspended and fixed to the said construction material with the said suspension rod fixed to the said construction material by the said clamping structure.

  In the above configuration, the lighting device further includes a hanging bracket fixed to the construction material, the hanging rod is fixed to the lamp, and the lamp is connected to the hanging bracket to fix the lighting fixture to the building construction. It may be suspended and fixed to the material.

  In the above configuration, the suspension fitting includes a U-shaped groove into which the suspension rod fits from the side, and sandwiches the upper and lower surfaces of the U-shaped groove with a plurality of polygonal nuts attached to the threaded portion of the suspension rod, The suspension fitting and the suspension rod may be connected and fixed.

  In the above configuration, the groove width of the U-shaped groove is larger than the outer diameter of the suspension rod and smaller than the two-surface width of the polygonal nut, and on the surface of the U-shaped groove opposite to the lamp mounting side, A concave portion having a wall portion having a gap dimension larger than the two-side width of the polygon nut and smaller than the maximum diameter of the polygon nut is provided, and among the polygon nuts, the lamp is suspended and fixed to the construction material. The nut to which a load due to gravity is applied in a state may be configured such that rotation is suppressed by the wall portion of the recess.

  In the above configuration, the lighting device includes a plurality of hanging rods connected to a lamp, and one of the hanging rods is fixed to the construction material using a terminal box, and the other hanging rod is the hanging bracket. The lamp may be suspended and fixed to the construction material by connecting and fixing the suspension rod.

  According to the present invention, in a hanging type lighting apparatus of a type in which a lamp is fixed to a construction material by tightening a hanging rod having a threaded portion with a nut, the mounting workability of the lighting apparatus can be improved and intense vibration and resonance frequency can be obtained. Even when mounted in an environment where the vibration is applied, a lighting device in which the nut does not come off and the lamp does not fall can be realized.

It is a front view which shows the hanging type illuminating device which concerns on embodiment of this invention. It is a perspective view which shows the hanging type illuminating device of FIG. It is a figure which shows the hanging metal fitting which concerns on this invention, (A) is a top view, (B) is a front view. It is explanatory drawing of the nut used for embodiment of this invention. It is the figure which compared the feature point of the hanging metal fitting which concerns on this invention with a prior art example, (A) is an Example of this invention, (B) is a prior art example. It is a perspective view which shows a feeder wire side hanging rod and a terminal box. It is a figure explaining the attachment method to the construction material of the hanging type illuminating device which concerns on embodiment of this invention. It is a figure which shows the modification of this invention. It is a figure which shows the other modification of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a front view showing a suspended illumination device according to the embodiment, and FIG. 2 is a perspective view showing the suspended illumination device.
The suspended illumination device 1 is an illumination device that is suspended from a construction material mounting surface S such as a relatively high ceiling in a factory, for example, and includes a lamp 10 and a pair of suspension rods 2 and 3 connected to the lamp 10. And. The lamp 10 is configured by supporting a light source (LED light source) 11 on the lower surface of a main body 12. The light source 11 is, for example, a rod-shaped LED light source resembling a fluorescent lamp. In the present embodiment, two light sources 11 are provided. This embodiment is an explosion-proof illumination device.
The main body 12 is a long box, and the light source 11 is provided along the longitudinal direction of the main body 12. A power supply device (not shown) for supplying power to the light source 11 is accommodated in the main body 12, and a lead wire or the like is connected to the power supply device. The lead wire L1 (see FIG. 7) from the power supply device passes through the feed line side suspension rod 3 and is exposed from the upper end portion 3B of the feed line side suspension rod 3.

The pair of hanging rods 2 and 3 are hollow pipes that are connected to the upper surface 12 </ b> A of the main body 12 at a distance. More specifically, on the upper surface 12A of the main body 12, two fixing tools 13 for screwing the hanging bracket side hanging rod 2 and the power supply line side hanging rod 3 are attached to be separated from each other. The lower ends 2 and 3 are fixed to the main body 12 by screwing the lower ends 2 </ b> A and 3 </ b> A to the fixture 13. The upper end 2B of the suspension bracket side suspension rod 2 is fixed to the construction material mounting surface S using the suspension bracket 20, and the upper end portion 3B of the feeder wire side suspension rod 3 is secured to the construction material attachment surface S using the terminal box 40. Has been.
On the construction material mounting surface S, a conduit P for passing a power line L2 (see FIG. 7) such as a commercial power source is fixed. Has been.

3A and 3B are diagrams showing the hanging bracket side hanging rod 2 and the hanging bracket 20, in which FIG. 3A is a plan view and FIG. 3B is a front view. FIG. 4 is an explanatory diagram of a lock nut used in the present embodiment.
As shown in FIG. 3 (B), a screw portion 2C is formed on the upper end portion 2B of the hanging bracket side suspension rod 2, and two lock nuts (supporting tools) 4A4B are separated from each other in the screw portion 2C. Are screwed together.

The hanging metal fitting 20 is, for example, a casting such as aluminum die-casting, and includes a pair of opposed wall portions 21 and a bottom portion 22 that connects the pair of wall portions 21 and is formed in a substantially U shape in a front view. A fixing portion 23 that extends outward is provided at the upper end of each wall portion 21, and the fixing bracket 23 is screwed to the construction material mounting surface S so that the hanging bracket 20 is attached to the construction material mounting surface S. (FIG. 1).
The lock nut 4A4B of the hanging bracket side suspension rod 2 is in contact with the bottom portion 22 from both sides, and the length M of the screw portion 2C of the suspension bracket side suspension rod 2 is the bottom portion 22 and The lock nut 4A4B is formed longer than the sum of the heights.

  The bottom portion 22 is formed with a U-shaped groove 24 notched in a U-shape through which the hanging bracket-side suspension rod 2 is inserted. The U-shaped groove 24 is formed by arranging a U-shaped opening on the front side or the back side when the suspension fitting 20 is viewed from the front. The groove width of the U-shaped groove is larger than the outer diameter of the hanging bracket side suspension rod 2 and smaller than the two-surface width of the hexagon nut.

  As shown in FIG. 3, stoppers 22 </ b> C higher than the seating surfaces 22 </ b> A and 22 </ b> B (see FIG. 5) are formed on the bottom 22 on both sides of the opening of the U-shaped groove 24. The hanger-side suspension bar 2 fitted in the groove 24 is prevented from escaping from the U-shaped groove 24 sideways. Therefore, when inserting the hanging bracket side suspension rod 2 into the U-shaped groove 24, the space between the lock nuts 4A4B is made larger than the height of the stopper 22C.

  FIG. 4 is an explanatory view showing the dimensional relationship of the lock nut 4A or 4B used in the present embodiment. It has the same shape as the “hex nut” defined in the JIS standard, the width across flats is denoted by B, and the width that becomes the maximum value when the nut rotates is denoted by e. The lock nut used in the present embodiment does not need to be a hexagon nut, but the lock nut 4A particularly needs to be a polygonal nut having an even-numbered planar shape, and is preferably an octagon or less and a quadrangle or more. That is, it is any one of a quadrangular shape, a hexagonal shape and an octagonal shape. The lock nut 4B may have any shape as long as it can be tightened, but may be the same as the lock nut 4A.

  FIG. 5 is a diagram in which the characteristics of the hanging metal fitting according to the present invention are compared with those of a conventional example. FIG. 5A is an example of the hanging metal fitting of the present invention, and FIG. As can be seen from a comparison between the two, in the conventional example (B), the wall portions 121 on both sides of the suspension fitting 120 have a distance e0 wider than the maximum width e of the lock nut 4A, and the suspension rod 2 is attached to the suspension fitting 120. In this state, the lock nut 4A can rotate while being in contact with the upper part of the seating surface 122A122B.

  On the other hand, in the embodiment of the present invention, the wall portions 21 on both sides of the hanging metal fitting 20 are set to a distance e0 wider than the maximum width e of the lock nut 4A, but the upper part of the seat surface 22A22B with which the lock nut 4A contacts (lamp mounting) A recess 25 is formed adjacent to the surface opposite to the side. The interval between the wall portions on both sides of the recess 25 is set to an interval B0 that is slightly larger than the dimension of the two-surface width B of the lock nut 4A used, and the lock nut 4A comes into contact with the upper part of the seating surface 22A22B to form the recess. The lock nut 4A cannot be rotated in the retracted state.

If the distance between the wall portions on both sides of the recess 25 is larger than the width B of the lock nut to be used and smaller than the maximum diameter e, the rotation of the lock nut can be suppressed. In order to avoid this, it is preferable that the wall distance B0 between the recesses is slightly larger than the two-sided width B of the lock nut, specifically 0.5 mm to 2 mm or less. It is preferable to set to about%. In the present embodiment, the recess 25 is integrally formed with the suspension fitting 20, but a member having the same distance B0 as the wall spacing of the recess 25 may be separately prepared and fixed to the seat surface of the suspension fitting. Good.

  FIG. 6 is a perspective view showing the feeder-side suspension rod 3 and the terminal box 40. A disc-shaped flange 5 is provided on the upper end 3 </ b> B of the power supply line-side suspension rod 3. More specifically, a screw portion is formed on the upper end portion 3 </ b> B of the feeder-line-side suspension rod 3, and this screw portion is screwed into a screw hole formed at the center of the flange 5. Here, since the power supply line side suspension rod 3 and the flange 5 are assembled so as not to be removed after assembly, it may be considered that they are integrated as a suspension rod with a flange.

The terminal box 40 is formed in a substantially cylindrical shape, and a plurality of fixing portions 41 extending outward are provided on the side surface (outer peripheral surface) of the terminal box 40, and the fixing portions 41 are screwed onto the construction material mounting surface S. By being stopped, the terminal box 40 is fixed to the construction material mounting surface S (FIG. 1).
In addition, a plurality of connection portions 42 for connecting the conduit P (FIG. 1) are provided on the side surface of the terminal box 40. In the present embodiment, a total of four connection portions 42 are formed so that the two connection portions 42 face each other, and a fixing portion 41 is formed between each connection portion 42. The connection portion 42 is a member that protrudes in a cylindrical shape from the side surface of the terminal box 40, and a screwed portion 42 </ b> A for screwing the conduit P is formed in the connection portion 42. The screwed portion 42 </ b> A penetrates the terminal box 40 and communicates with the hollow portion of the terminal box 40.

  A hook fitting (not shown) for temporarily securing the feeder-side suspension rod 3 is attached in the terminal box 40, and a chain 32 screwed to the upper surface of the flange 5 of the feeder-line suspension rod 3 is attached. The feeder-side suspension rod 3 is temporarily secured to the terminal box 40 by being hooked on the hook metal fitting in the terminal box 40.

  The terminal box 40 includes a connection ring 50 that connects the flange 5 of the power supply wire side suspension rod 3 to the terminal box 40. The connection ring 50 is rotatably supported by the terminal box 40 by being assembled and fixed to the terminal box 40.

  Next, a method for assembling the hanging illumination device 1 will be described. FIG. 7 is a front view showing the suspended illumination device 1 during attachment.

  First, the suspension metal fitting 20 and the terminal box 40 are fixed to the construction material mounting surface S, and the electric wire P is connected to the terminal box 40, and the power line L <b> 2 passing through the electric wire P is connected from the connection portion 42 of the terminal box 40 to the terminal. It exposes from the lower part of the connection ring 50 through the inside of the box 40 and the connection ring 50.

  Next, as shown in FIG. 3, the hanging bracket side hanging rod 2 is inserted into the U-shaped groove 24 of the hanging bracket 20. Since the U-shaped groove 24 is formed in a U shape in which the hanging bracket side hanging rod 2 is fitted from the side, the hanging bracket side hanging rod 2 is simply fitted into the U-shaped groove 24 from the side. 2 can be easily engaged with the hanging bracket 20. At this time, the lock nut 4A4B is spaced apart from the thickness of the bottom portion 22 (stopper 22C) of the hanging bracket 20.

  Next, the chain 32 screwed to the upper surface of the flange 5 of the power supply line side suspension rod 3 is hooked on the hook metal fitting in the terminal box 40, and the power supply line side suspension rod 3 is temporarily fixed. The lead wire L1 extending from the rod 3 and the power supply line L2 extending from the terminal box 40 are connected.

  Thereafter, the flange 5 and the terminal box 40 are connected and fixed using the connecting ring 50.

  Finally, as shown in FIG. 1, the lock nut 4A4B of the suspension bracket side suspension rod 2 is tightened to complete the assembly of the suspended illumination device 1. When the upper lock nut 4 </ b> A is appropriately tightened and adjusted in height, the lock nut 4 </ b> A is accommodated in the recess 25 of the hanging bracket 20. Since the wall distance between the recesses is slightly wider than the width B of the lock nut 4A, the lock nut 4A is accommodated in the recess 25 at a position where the width of the lock nut 4A is parallel to the wall of the recess. Cannot rotate.

  Further, the lock nut 4B is tightened, and the hanging bracket side hanging rod 2 and the hanging bracket 20 are connected and fixed as shown in FIG. In this way, the hanging bracket 20 is connected and fixed by sandwiching the upper and lower surfaces of the U-shaped groove by two lock nuts attached to the threaded portion of the hanging bracket side suspension rod 2. Since the distance between the two lock nuts 4A4B is smaller than the height of the stopper 22C, even if a force such as a wind pressure load is applied, the U-shape of the hanging bracket side suspension rod 2 fitted into the U-shaped groove 24 by the stopper 22C. Escape to the side from the groove 24 can be prevented.

  By the way, since the hanging bracket side suspension rod 2 fixed to the lamp 10 is pulled downward by gravity after the mounting, a load is always applied to the upper lock nut 4A. In this state, if the lighting device 1 is vibrated vigorously, particularly at a frequency at which the vicinity of the suspension rod resonates, a force is generated that causes the suspension rod to move vigorously and rotate the lock nut 4A in a loosening direction. However, according to the configuration of the present invention, since the lock nut A does not rotate, the lock nut does not loosen and come off from the hanging bracket no matter what vibration is applied.

  The lower lock nut B, which is not subjected to a load due to gravity, does not need to adopt a detent structure because the lock nut does not loosen no matter what vibration is applied.

  As described above, according to the present embodiment, the suspension bracket-side suspension rod 2 connected to the lamp 10 is provided, and the suspension bracket-side suspension rod 2 is fixed to the construction material mounting surface S using the suspension bracket 20. The suspension fitting 20 has a U-shaped groove 24 into which the suspension fitting-side suspension rod 2 is fitted from the side, and further, a lock nut 4 </ b> A to which a load due to gravity is applied while being suspended and fixed to the construction material S is housed in the recess 25 and rotated. By adopting such a structure, the hanging bracket side hanging rod 2 can be easily engaged with the hanging bracket 20, the mounting workability of the hanging type lighting device 1 can be improved, and the lamp can be applied no matter what vibration is given. Becomes a lighting device that does not come off the hanging bracket.

  However, the above embodiment is an aspect of the present invention, and it is needless to say that the embodiment can be appropriately changed without departing from the gist of the present invention. For example, in the above embodiment, the lamp 10 includes a rod-shaped LED light source as a light source. However, the light source is not limited to this, and for example, a substrate including an LED element such as SMD is directly attached to the main body 12 of the lamp. An attached structure may be used. Moreover, in the said embodiment, although a pair of half ring body 51 was couple | bonded with the screw 53 as a stopper, the stopper of the ring body 51 is not limited to a screw.

  Moreover, in the said embodiment, although the suspension type illuminating device 1 was provided with a pair of suspension rods 2 and 3 in order to support the rod-shaped light source 11, it is not limited to this, For example, the suspension rod 2 You may have only.

  For example, as shown in FIG. 8, the hanging rod 202 is not used, the hanging rod 202 is fixed to the mounting surface S of the construction material, and the lower end 202B of the hanging rod 202 is provided with a threaded portion having a smaller step diameter, and the lamp body 212 The lamp may be fixed by sandwiching the upper portion between the step surface 202C of the suspension rod 202 and the lock nut 204A. In this embodiment, the suspension rod 202 is hollow, and the power supply line L passes through the inside.

  In the structure shown in FIG. 8, the nut to which the load due to gravity is suspended and fixed to the construction material is the lock nut 204 </ b> A on the lower side of the lamp. Therefore, the lock nut 204A needs to have a non-rotating structure.

  A well-known technique and a commercially available product can be widely used as the lock nut detent mechanism. However, a method of making a hole in a suspension bar using a grooved nut as defined in JISB1170 and driving a spring pin or the like to stop rotation is a hole into which a pin is driven when the lighting device according to the present invention is attached. Is unfavorable because it needs to be opened on site and requires machining at a high place.

  If the suspension rod is not a thin-walled pipe, it is possible to prevent the lock nut from loosening by combining the lock bearing lock nut AN and washer AW defined in JIS B1554 by forming a keyway on the surface of the suspension rod threaded portion. is there. A double nut obtained by simply combining two nuts having the same screw standard has a certain effect. However, as described in Patent Document 1, a problem may arise when a lamp is attached to a place where vibration is applied. In order to obtain a reliable detent effect in accordance with the gist of the present invention, various known locking nut structures (see, for example, Japanese Utility Model Publication No. 3-568) can be used. If the dimensions match, a commercially available product such as a “hard lock nut” (trade name) may be used.

  The screw provided on the suspension rod may be a metric screw or a metric fine screw as defined in JIS B0205. Moreover, the screw used for a pipe, for example, the "G" standard prescribed | regulated to JISB0202.

  As shown in FIG. 8, the engaging protrusion 227 is provided on the hanging rod 202, the engaging recess 226 is provided on the upper part of the lamp body 212, and the engaging protrusion 227 is engaged with the engaging recess 226. It is good also as a structure where the lamp main body 212 does not rotate.

  9, the mounting member 340 is fixed to the construction material mounting surface S, the suspension bar 302 is fixed to the mounting member 340, and the lower end portion 302B of the suspension bar 302 has the same size as the outer diameter of the suspension bar 302. The lower end portion 302B of the hanging rod 302 is inserted into the upper portion of the lamp body 312 and the upper portion of the lamp body 312 is fastened and fixed by a pair of upper and lower lock nuts 304A304B. In such a structure, the nut that is loaded with gravity while being suspended and fixed to the construction material becomes the lock nut 304A on the lower side of the lamp, and the same effect can be obtained by making the lock nut 304A a non-rotating structure. Can be obtained. The upper lock nut 304B does not need to have a detent structure.

  As in the embodiment shown in FIGS. 1 to 7, if the suspension rod is fixed to the lamp body and connected to the suspension fitting 20 fixed to the construction material, the suspension fitting 20 is locked to the lock nut 20 as in this embodiment. The structure in which the concave portion 25 having a wall interval slightly larger than the width of two sides of 4A is provided and the lock nut 4A on the upper side in the gravitational direction is accommodated in the concave portion 25 does not require any additional parts. It is most preferable because the thickness does not become unnecessarily thick.

  In addition, in the structure shown in FIG. 9, is a recess having wall portions slightly larger than the width of the two surfaces of the lock nut A formed around the portion where the lower lock nut 304A contacts the upper portion of the lamp main body 312? The same effect as that of the embodiment shown in FIG. 3 can be obtained by fixing the member forming the same wall portion to the lower surface of the upper portion of the main body 312 of the lamp.

  In this structure, when the height of the lock nut 304A on the lower side is adjusted by appropriately tightening, it is housed in a recess (not shown) of the main body 312 of the lamp. Since the interval between the recesses is slightly wider than the width B of the lock nut 304A, the lock nut 304A is accommodated in the recess at a position where the width of the lock nut 304A is parallel to the wall of the recess, and the lock nut 304A rotates further. Can not. Further, the upper lock nut 304B is tightened to connect and fix the hanging bracket side hanging rod 302 and the lamp body 312 as shown in FIG.

As described above, the configuration of the present invention provides a hanging type lighting device that suppresses the risk of falling due to severe vibration or resonance by adding a little contrivance to various hanging type lighting devices that have been conventionally implemented. be able to.

DESCRIPTION OF SYMBOLS 1 Hanging type lighting device 2, 3 Hanging rod 3B Upper end 4A, 4B Lock nut (supporting tool)
5 Flange 10 Lamp 20 Suspension bracket 22A, 22B Seat 22C Stopper 24 U-shaped groove 25 Recess 40 Terminal box 42 Connection 50 Connection ring 50A Inner circumferential surface 51 Ring body 53 Screw (stopper)
S Construction material mounting surface

Claims (6)

In a hanging type lighting device in which a lamp is suspended and fixed to a construction material via a hanging rod,
A threaded portion is formed at the end of the hanging rod,
It has a sandwiching structure by a combination of a pair of nuts incorporated in this threaded part, or a nut and a hanging bar step part,
A hanging type illumination device characterized by having a structure in which a nut to which a load due to gravity is applied is not rotated in a state where the lamp is suspended and fixed to the construction material.   2. The hanging type illumination device according to claim 1, wherein the lamp is suspended and fixed to the construction material by the suspension rod fixed to the construction material by the sandwiching structure. Further comprising a hanging bracket fixed to the construction material,
The hanging rod is fixed to the lamp,
The hanging illumination device according to claim 1, wherein the lamp is suspended and fixed to the construction material by connecting and fixing the hanging bracket and the hanging rod. The suspension fitting includes a U-shaped groove into which the suspension rod fits from the side,
The suspension according to claim 3, wherein the suspension fitting and the suspension rod are connected and fixed by sandwiching the upper and lower surfaces of the U-shaped groove with a plurality of polygonal nuts attached to the threaded portion of the suspension rod. Shape lighting device. The groove width of the U-shaped groove is larger than the outer diameter of the suspension rod and smaller than the two-surface width of the polygon nut,
On the surface opposite to the lamp mounting side of the U-shaped groove, there is provided a recess having a wall portion with a spacing dimension that is larger than the width of the polygon nut and smaller than the maximum diameter of the polygon nut,
The said nut is comprised so that rotation by the wall part of the said recessed part may be suppressed by the nut which receives the load by gravity in the state by which the said lamp was suspended and fixed to the said construction material among the said polygon nuts. Pendant lighting device. A plurality of suspension rods connected to the lamp, one of the suspension rods is fixed to the construction material using a terminal box,
6. The lamp according to claim 3, wherein the lamp is suspended and fixed to the construction material by connecting and fixing the suspension bracket and the suspension bar to each other. 6. Pendant lighting device.