JP2023154750A - Cable rack earth metal fitting - Google Patents

Abstract

To provide a cable rack earth metal fitting capable of largely reducing an operation of electrically connecting a cable rack with an upper face cover and a lower face cover.SOLUTION: A cable rack earth metal fitting 1 for electrically connecting a ladder-like cable rack CR with an upper face cover TC and a lower face cover BC that are attached to the cable rack CR comprises: a first connection part 26 electrically connected with the upper face cover TC; a second connection part 27 that is provided at a position opposed to the first connection part 26 and electrically connected with the lower face cover BC; and a third connection part 28 that is provided at a connection part where the first connection part 26 is connected with the second connection part 27 and electrically connected with a side face of a master girder CR1.SELECTED DRAWING: Figure 1

Description

The present invention relates to a cable rack grounding fitting for electrically connecting a cable rack and a cover of the cable rack.

A ladder-type cable rack used for wiring power cables, communication cables, etc. has a ladder shape that includes a pair of long main girders and a plurality of child girders installed between the main girders. The cable is disposed within a housing space surrounded by a master girder and a child girder. A plurality of such cable racks are arranged along a wiring route, and the ends of the main girders are connected to each other by fittings or the like.

In order to ensure the protection and safety of the installed cables, a cable rack is attached with either or both of a top cover that covers the top of the storage space and a bottom cover that covers the bottom of the storage space. There are cases. The top cover and the bottom cover are arranged along the parent girder and have a shorter longitudinal dimension than the cable rack. Therefore, a larger number of upper and lower covers than the number of cable racks are attached to the cable rack.

The cable rack, the top cover, and the bottom cover are made of conductive metal, and have a function to release leakage current when a leakage occurs in the cable. When multiple cable racks are connected together, adjacent cable racks are electrically connected using joints or ground bond wires, and the cable rack at the end is connected to the ground electrode. In addition, as with the cable rack, the top cover and the bottom cover are also connected to each other by connecting adjacent top covers and adjacent bottom covers to each other using ground bond wires or cover grounding fittings (for example, see Patent Document 1). The terminal top cover and bottom cover are connected to the ground electrode.

Japanese Patent Application Publication No. 09-163539

As mentioned above, conventionally, it was necessary to electrically connect and ground the cable rack, the top cover, and the bottom cover, respectively. Furthermore, since the number of top covers and bottom covers is greater than the number of cable racks, as the path length of the cable racks becomes longer, the number of tasks required to electrically connect adjacent covers increases significantly. Further, the top cover and the bottom cover are attached to the cable rack after the cables are installed along the wiring route, and then adjacent covers are electrically connected to each other. Therefore, if the cable rack is installed at a high place, the aerial work platform must be moved several times depending on the length and number of covers, and the work platform must be raised and lowered each time to electrically remove the cover. Connection work must be done.

As described above, conventionally, there has been a problem in that the work of electrically connecting the cable rack and the top cover and the bottom cover is very time-consuming.

SUMMARY OF THE INVENTION An object of the present invention is to provide a grounding fitting for a cable rack that can significantly reduce the work required to electrically connect the cable rack to the top cover and the bottom cover.

In order to solve the above problem, the invention according to claim 1 provides a ladder-like cable rack including a pair of elongated main girders and a plurality of child girders installed between the main girders, and a first cover attached to one side of the cable rack so as to cover between the pair of main girders; and a second cover on the opposite side of the one side of the cable rack so as to cover between the pair of main girders. A grounding fitting for a cable rack used for a second cover attached to a surface of the cable rack, the grounding fitting being arranged along the width direction of the main girder orthogonal to the longitudinal direction of the main girder and the child girder, and a first connection part that is electrically connected to the first cover; a second connection part that is provided at a position opposite to the first connection part and is electrically connected to the second cover; It is characterized by comprising a third connecting part that is provided at a connecting part that connects the first connecting part and the second connecting part and is electrically connected to a side surface of the master girder.

The invention according to claim 2 is the cable rack grounding fitting according to claim 1, in which the first cover includes a first cover main body that covers between the pair of main girders, and a first cover main body that covers between the pair of main girders. and a first side edge portion that is bent so that both sides of the main spar are bent along the width direction of the main spar, and the second cover includes a second cover main body that covers between the pair of main spars; Both sides of the second cover body include second side edge portions that are bent along the width direction of the main girder, and the first connecting portion is attached to the first side edge portion. The second connection portion is press-contacted and electrically connected to the second side edge portion, and the third connection portion is press-contacted to the side surface of the parent girder. It is characterized in that it is electrically connected.

The invention according to claim 3 is the cable rack grounding fitting according to claim 2, wherein the first connecting portion is inserted between the side surface of the master girder and the first side edge portion. a first pressure contact portion; a first opposing portion that faces the first pressure contact portion on the outer surface side of the first side edge portion; and a first screw hole provided in the first opposing portion. , a first bolt that is screwed into the first screw hole and press-contacts the first side edge portion, and press-contacts the first press-contact portion to the inner surface side of the first side edge portion; The second connection part includes a second pressure contact part inserted between the side surface of the master girder and the second side edge part, and a second pressure contact part inserted between the side surface of the master girder and the second side edge part, and the second connection part on the outer surface side of the second side edge part. a second facing part facing the pressure contact part of No. 2; a second screw hole provided in the second facing part; and a second facing part that is screwed into the second screw hole and connected to the second side edge part. and a second bolt that presses the second press-contact part to the inner surface of the second side edge, and the third connection part includes a third bolt facing the side surface of the parent girder. a third screw hole provided in the third opposing portion, and a third bolt that is screwed into the third screw hole and press-contacted to the side surface of the parent girder. It is characterized by

According to a fourth aspect of the invention, in the cable rack grounding fitting according to the third aspect, the first pressure contact portion includes a corner portion that bites into and breaks the surface treatment film of the first side edge portion. The second press-contact portion is characterized in that it includes a corner portion that bites into and breaks the surface treatment film of the second side edge portion.

The invention according to claim 5 is the grounding fitting for a cable rack according to claim 4, in which the first pressure contact portion and the second pressure contact portion include a plate member provided with a slit-like notch. It is formed by being bent along the slit direction at the cutout portion, and the corner portions of the first pressure contact portion and the second pressure contact portion are formed by twisting the edge of the cutout. do.

The invention according to claim 6 is the cable rack grounding fitting according to claim 2, wherein the cable rack has the child girder installed on one end side in the width direction of the parent girder, and the third The connecting portion is characterized in that the connecting portion is disposed on one end side where the child girder is constructed in the width direction of the parent girder.

The invention according to claim 7 is the cable rack grounding fitting according to claim 1, in which the cable rack and the first cover or the second cover attached to the cable rack are electrically connected to each other. A locking metal fitting is provided which is used in conjunction with the connection, and the locking metal fitting is bent so that a cross section of a substantially rectangular plate material is substantially L-shaped to form a first surface and a second surface. a connecting portion connected to either the first connecting portion or the second connecting portion is provided on the first surface, and one end in the width direction of the parent girder is provided on the second surface. If only the first cover is attached to the cable rack, the locking fitting connected to the second connection part is connected to the parentheses. The cable rack and the first cover are electrically connected to each other by the first connection part and the third connection part by being locked to the girder, and only the second cover is connected to the cable rack. If the cable rack is attached, the locking fitting connected to the first connection part is locked to the main girder, and the cable rack is connected to the cable rack by the second connection part and the third connection part. and the second cover are electrically connected.

According to the invention described in claim 1, the cable rack, the first cover, and the second cover can be electrically connected, so that at the end, only the cable rack is connected to the ground electrode. It is possible to ground the entire cable rack, first cover and second cover. Furthermore, in the past, adjacent covers were electrically connected to each other, so it was necessary to perform electrical connection work for each of the top cover and the bottom cover. In contrast, according to the present invention, electrical connections can be made between the top cover and the bottom cover at the same time by simply connecting one cable rack grounding fitting, which greatly reduces the work required to electrically connect the covers, etc. It is possible to reduce

According to the invention set forth in claim 2, the first connection portion, the second connection portion, and the third connection portion of the grounding fitting for a cable rack are connected to the first cover, the second cover, and the cable rack. Since electrical connections are made by pressure welding, the work can be done more easily and quickly than with a configuration in which a conductive hole is provided in the cover and a bolt is inserted into the conductive hole to make the connection. It is possible. In addition, even if the surface of the cable rack or cover has been treated with non-conductive surface treatment to provide weather resistance, rust prevention, etc., the surface of the cable rack or cover can be Since the process can be broken, it is possible to reliably electrically connect the cable rack and the first cover and the second cover.

According to the invention set forth in claim 3, the first side edge of the first cover is sandwiched between the first pressure contact portion and the first opposing portion, and the second pressure contact portion and the second opposing portion are sandwiched between the first side edge portion of the first cover. Since the second side edge of the second cover is sandwiched between the two sides, the cable rack grounding fittings can be easily and quickly attached to the sides of the cable rack, first cover, and second cover. It is. In addition, by simply screwing the bolts into the screw holes provided in the first opposing part, the second opposing part, and the third opposing part and tightening them, each bolt can be attached to the cable rack, the first cover, and the third opposing part. Since it can be brought into pressure contact with the second cover, the work can be done easily and quickly.

According to the invention set forth in claim 4, since the first press-contact part and the second press-contact part are provided with corners that bite into and break the surface treatment films of the first cover and the second cover, It is possible to apply pressure with bolts to ensure electrical connections.

According to the invention set forth in claim 5, bending is used to form the first press-contact portion and the second press-contact portion, and the corner portion is formed by twisting the edge of the notch. As shown in the figure, there is no need to provide protrusions by blank processing or punching, and it is possible to reduce the number of steps for producing a grounding fitting for a cable rack. In addition, in blanking and punching, the shape of the protrusions formed may change due to wear of the mold (such as blunting of acute edges), but in the present invention, the torsion during bending is used. , the effects of mold wear can be reduced. Therefore, it is possible to stably obtain a corner portion with little change in shape.

According to the invention set forth in claim 6, in the width direction of the parent girder, the third connecting portion is disposed on one end side where the child girder is constructed and the rigidity is high. By press-contacting the main girder to the main girder, the main girder will not be deformed.

According to the invention set forth in claim 7, by using the locking metal fitting that can be used in combination with the grounding metal fitting for the cable rack, the cable rack and the first cover or the second cover attached to the cable rack are electrically connected. It is possible to connect to Therefore, even if the cable rack has a single-sided cover, it is possible to effectively utilize the cable rack grounding fitting of the present invention without preparing a separate grounding fitting.

FIG. 2 is a perspective view showing a usage pattern in which a cable rack grounding fitting according to an embodiment of the present invention is attached to a cable rack. They are a first perspective view (a) showing a cable rack grounding fitting from the front side, and a second perspective view (b) showing the fitting main body from the back side. They are a front view (c) of the metal fitting main body, a XX sectional view of (c), a side view of the metal fitting main body (d), and a back view (e) of the metal fitting main body 2. They are a YY sectional view (f) in FIG. 3(e) and a developed view (g) of the metal fitting body. It is an explanatory view showing a procedure for attaching a cable rack grounding fitting to a cable rack. FIG. 3 is a sectional view showing a state in which the cable rack grounding fitting is attached to the cable rack. FIG. 2 is an explanatory diagram comparing a case where connected cable racks and the like are electrically connected by a conventional method and a case where a grounding fitting for cable racks is used. It is a perspective view which shows the grounding metal fitting for cable racks, and the locking metal fitting used together. FIG. 3 is a sectional view showing a state in which the cable rack and the top cover are electrically connected using a cable rack grounding fitting and a locking fitting. FIG. 3 is a perspective view showing the configuration of a cable rack, a top cover, and a bottom cover.

The present invention will be described below based on the illustrated embodiments.

(Embodiment 1)
FIG. 1 is a perspective view showing how a cable rack grounding fitting 1 according to this embodiment is used. The cable rack grounding fitting 1 is a fitting for electrically connecting the cable rack CR to the top cover (first cover) TC and bottom cover (second cover) BC of the cable rack CR.

Although this embodiment describes the cable rack grounding fitting 1 that is attached to the cable rack CR installed in the substantially horizontal direction, the cable rack grounding fitting 1 of this embodiment is installed in the substantially vertical direction. It is also possible to apply the present invention to a cable rack CR installed in a cable rack CR and a cover attached to the front and rear surfaces of this cable rack CR.

Here, the cable rack CR, top cover TC, and bottom cover BC will be explained. As shown in FIG. 10, the cable rack CR of this embodiment is a ladder type cable rack used for wiring power cables, communication cables (not shown), and the like. The cable rack CR has a ladder shape including a pair of elongated main girders CR1 and CR2 and a plurality of child girders CR3 installed between the main girders CR1 and CR2. The cable is disposed within a housing space surrounded by parent girders CR1 and CR2 and child girder CR3.

The cross section perpendicular to the longitudinal direction of the main girders CR1 and CR2 is approximately U-shaped with the opening facing inward in order to increase rigidity, and the central portion protrudes toward the inside of the cable rack CR. There is. At both ends of the parent girders CR1 and CR2, mounting holes are provided to which joint fittings are connected when connecting a plurality of cable racks CR.

The child beam CR3 is a rod-shaped body whose cross section perpendicular to the longitudinal direction is approximately U-shaped. The child beams CR3 are installed at predetermined intervals on one end side, for example, the lower end side, in the width direction of the parent beams CR1, CR2, which are orthogonal to the longitudinal direction of the parent beams CR1, CR2 and child beam CR3.

The cable rack CR has either or both of a top cover TC that covers the top of the storage space and a bottom cover BC that covers the bottom of the storage space to ensure the protection and safety of the installed cables. may be installed. The upper surface cover TC and the lower surface cover BC are arranged along the master girders CR1 and CR2 and have a length shorter than the cable rack CR. Therefore, a larger number of upper covers TC and lower covers BC than the number of cable racks CR are attached to the cable rack CR.

The top cover TC includes a top cover main body (first cover main body) TC1 that covers between the pair of main girders CR1 and CR2, and both sides of the top cover main body TC1 are bent along the width direction of the main girders CR1 and CR2. and a top cover side edge (first side edge) TC2. Similarly, the bottom cover BC has a bottom cover main body (second cover main body) BC1 that covers between the pair of main girders CR1 and CR2, and both sides of the bottom cover main body BC1 are arranged along the width direction of the main girders CR1 and CR2. The lower cover side edge portion (second side edge portion) BC2 is bent.

The cable rack CR, the top cover TC, and the bottom cover BC are formed of conductive metal plates. Furthermore, the surfaces of the cable rack CR, top cover TC, and bottom cover BC are coated with a non-conductive surface treatment film to provide weather resistance, rust prevention, and the like. Note that the same top cover TC and bottom cover BC may be used.

Next, the cable rack grounding fitting 1 will be explained. FIG. 2 is a first perspective view (a) showing the cable rack grounding fitting 1 from the front side, and a second perspective view (b) showing the fitting main body 2 constituting the cable rack grounding fitting 1 from the back side. It is. Further, FIG. 3 is a front view (c) of the metal fitting main body 2, a sectional view taken along line XX in (c), a side view (d) of the metal fitting main body 2, and a rear view (e) of the metal fitting main body 2. Furthermore, FIG. 4 is a YY sectional view (f) of FIG. 3(e) and a developed view (g) of the metal fitting main body 2.

The cable rack grounding fitting 1 includes a rod-shaped fitting body 2, a top cover bolt (first bolt) 3 that is screwed into the fitting body 2, and a bottom cover bolt (second bolt) 4. , a rack bolt (third bolt) 5. As shown in FIG. 1, the cable rack grounding fitting 1 is arranged along the width direction of the main beam CR1 at a position avoiding the connection hole for connection of the main beam CR1.

The rack bolts 5 are longer than the top cover bolts 3 and the bottom cover bolts 4 in order to connect to the cable rack CR. Further, the top cover bolt 3, the bottom cover bolt 4, and the rack bolt 5 are recessed-end bolts in which only the peripheral edge of the tip surface is annularly projected in the insertion direction. The tips of the top cover bolts 3, bottom cover bolts 4, and rack bolts 5 are pressed against the main girder CR1, the top cover TC, and the bottom cover BC, thereby breaking the surface treatment film and contacting the base metal. .

The metal fitting main body 2 is obtained by bending a substantially rectangular metal substrate 2A shown in FIG. , is formed into a rod-shaped body having a front part 21, left and right side parts 22, 23, and a pair of back parts 24, 25.

The metal fitting main body 2 has a first connection part 26 that is electrically connected to the top cover TC, and a second connection that is provided at a position opposite to the first connection part 26 and is electrically connected to the bottom cover BC. 27, and a third connecting portion 28 provided at a connecting portion connecting the first connecting portion 26 and the second connecting portion 27 and electrically connected to the side surface of the main girder CR1. There is.

The first connecting portion 26 presses against the upper cover side edge portion TC2 and electrically connects with the upper cover TC. Further, the second connecting portion 27 is in pressure contact with the lower cover side edge BC2 to electrically connect with the lower cover BC. Further, the third connecting portion 28 is pressed into contact with the side surface of the master girder CR1 to electrically connect it. Note that "to electrically connect by pressure contact" means to break the surface treatment films of the cable rack CR, top cover TC, and bottom cover BC to contact the bare metal.

The first connection portion 26 includes first press-contact portions 261 and 262 inserted between the side surface of the main girder CR1 and the top cover side edge TC2, and a first pressure contact portion 261 and 262 inserted between the side surface of the main girder CR1 and the top cover side edge TC2, and a first A first opposing portion 263 that faces the pressure contact portions 261 and 262, a first screw hole 264 provided in the first opposing portion 263, and a top cover side edge that is screwed into the first screw hole 264. It is provided with a top cover bolt 3 that presses against TC2 and presses the first pressure contact parts 261, 262 against the inner surface of the top cover side edge TC2.

The first press-contact parts 261 and 262 are provided at the upper ends of the pair of back surfaces 24 and 25 using a pair of slit-shaped notches 2A1 and 2A2 provided in the metal substrate 2A. Among the first pressure contact parts 261 and 262, the outer corner of one pressure contact part 262 is designed to avoid interference with the top cover main body TC1 when attaching the cable rack grounding fitting 1 to the cable rack CR. It is cut out diagonally. Note that this diagonal notch may also be provided on the outside of the other first pressure contact portion 261.

In addition, as shown in FIG. 4(f), the root portions of the first press-contact parts 261, 262 have knife-like corners 261a, 262a that cut into and break the surface treatment film of the upper cover side edge TC2. It is provided. These corners 261a and 262a are formed by twisting the edges of the notches 2A1 and 2A2 by bending the notches 2A1 and 2A2 of the metal substrate 2A shown in FIG. 4(g) along the slit direction. .

Oval contact portions 261b and 262b that protrude toward the back surface are provided on the back surface portions of the first pressure contact portions 261 and 262. These contact parts 261b and 262b are provided to reduce friction by reducing the contact area between the metal fitting body 2 and the side surface of the main girder CR1 when attaching the cable rack grounding fitting 1 to the cable rack CR. ing.

The first opposing portion 263 is provided at the upper end of the front portion 21 . The first screw hole 264 is arranged approximately at the center of the first opposing portion 263 in the width direction. The first screw hole 264 is formed into a cylindrical shape by burring, and a female thread is formed on the inner peripheral surface of the hole.

The second connection part 27 includes second press-contact parts 271 and 272 inserted between the side surface of the main girder CR1 and the lower cover side edge BC2, and a second pressure contact part 271 and 272 inserted between the side surface of the main girder CR1 and the lower cover side edge BC2, and a second pressure contact part 271 and 272 inserted between the side surface of the main girder CR1 and the lower cover side edge BC2. A second opposing portion 273 facing the pressure contact portions 271 and 272, a second screw hole 274 provided in the second opposing portion 273, and a lower cover side edge that is screwed into the second screw hole 274. It is provided with a lower cover bolt 4 that presses against the BC2 and presses the second press contact parts 271, 272 against the inner surface of the lower cover side edge BC2.

The second press-contact parts 271 and 272 are provided at the lower ends of the pair of back parts 24 and 25 using a pair of slit-shaped notches 2A3 and 2A4 provided in the metal substrate 2A. Among the second pressure contact parts 271 and 272, the outer corner of one pressure contact part 272 is designed to avoid interference with the bottom cover main body BC1 when attaching the cable rack grounding fitting 1 to the cable rack CR. It is cut out diagonally. This diagonal notch may also be provided at the outer corner of the other second pressure contact portion 271.

Further, the root portions of the second pressure contact portions 271 and 272 are provided with knife-like corner portions 271a and 272a that cut into and break the surface treatment film of the lower cover side edge portion BC2. These corner portions 271a, 272a are formed similarly to the corner portions 261a, 262a of the first pressure contact portions 261, 262, and have the same shape, so a detailed description thereof will be omitted.

Oval contact portions 271b and 272b that protrude toward the back surface are provided on the back surface portions of the second pressure contact portions 271 and 272. These contact parts 271b and 272b are provided to reduce friction by reducing the contact area between the metal fitting body 2 and the side surface of the main girder CR1 when attaching the cable rack grounding fitting 1 to the cable rack CR. ing.

The second opposing portion 273 is provided at the lower end of the front portion 21 . The second screw hole 274 is arranged approximately at the center of the second opposing portion 273 in the width direction. The second threaded hole 274 is formed into a cylindrical shape by burring, and a female thread is formed on the inner peripheral surface of the hole.

The third connecting portion 28 is screwed into a third opposing portion 281 facing the side surface of the parent girder CR1, a third screw hole 282 provided in the third opposing portion 281, and a third screw hole 282. The rack bolt 5 is also provided with a rack bolt 5 which presses against the side surface of the main girder CR1. The third screw hole 282 is formed into a cylindrical shape by burring, and a female thread is formed on the inner peripheral surface of the hole.

The third opposing part 281 and the third screw hole 282 are provided on the lower side of the front part 21 of the metal fitting main body 2. This is to prevent the rack bolt 5 screwed into the third screw hole 282 from coming into contact with and pressing the main spar CR1, thereby preventing the main spar CR1 from being deformed and bent inward. Since the child spar CR3 is arranged on the lower side of the fitting body 2, that is, on the lower end side in the width direction of the main spar CR1, and has high rigidity, it is possible to prevent the main spar CR1 from being deformed by the pressure of the rack bolts 5. It is.

In addition, the metal fitting main body 2 has a shape that is rotationally symmetrical about a central axis C along the front-rear direction of the metal fitting main body 2, except for the third connecting portion 28. That is, the first connecting portion 26 and the second connecting portion 27 have the same shape.

Next, the operation according to the above embodiment will be explained. FIG. 5 shows the procedure for attaching the cable rack grounding fitting 1 to the cable rack CR. As shown in Figure (a), the cable rack grounding fitting 1 is designed so that the first pressure contact part 262 and the second pressure contact part 272 do not interfere with the top cover side edge TC2 and the bottom cover side edge BC2. , it is pressed against the side surface of the main girder CR1 in an obliquely inclined state.

Thereafter, the cable rack grounding fitting 1 is rotated in the direction of arrow Z. As a result, as shown in FIG. 5(b) and FIG. 263 faces the outer surface side of the upper cover side edge TC2. Similarly, the second pressure contact parts 271 and 272 are inserted between the side surface of the main girder CR1 and the lower cover side edge BC2, and the second opposing part 273 is inserted on the outer surface side of the lower cover side edge BC2. opposite.

When the top cover bolt 3 is tightened in this state, the tip of the top cover bolt 3 bites into the outer surface of the top cover side edge TC2, breaks the surface treatment film, and comes into contact with the base metal. In addition, by tightening the top cover bolt 3, the first pressure contact parts 261 and 262 are brought into pressure contact with the inner surface of the top cover side edge TC2, and the corner parts 261a and 262a break the surface treatment film and metallize the base metal. come into contact with. Thereby, the cable rack grounding fitting 1 and the top cover TC are electrically connected.

Similarly, when the lower cover bolt 4 is tightened, the tip of the lower cover bolt 4 bites into the outer surface of the lower cover side edge BC2, breaks the surface treatment film, and comes into contact with the base metal. Further, by tightening the lower cover bolt 4, the second pressure contact parts 271 and 272 are brought into pressure contact with the inner surface of the lower cover side edge BC2, and the surface treatment film is broken by the corner parts 271a and 272a, and the base metal is come into contact with. Thereby, the cable rack grounding fitting 1 and the bottom cover BC are electrically connected.

Further, when the rack bolt 5 is tightened, the tip of the rack bolt 5 bites into the side surface of the main girder CR1, breaks the surface treatment film, and comes into contact with the base metal. Thereby, the cable rack grounding fitting 1 and the cable rack CR are electrically connected. Further, the cable rack CR, the top cover TC, and the bottom cover BC are electrically connected via the cable rack grounding fitting 1.

FIG. 7 is a schematic diagram showing a rack path including a plurality of cable racks CR and a plurality of top covers TC and bottom covers BC attached to the cable racks CR. Each straight line in the horizontal direction indicates one cable rack CR, one top cover TC and one bottom cover BC, and the black circles marked at both ends of each straight line indicate each cable rack CR and each top cover. The ends of TC and bottom cover BC are shown. In this embodiment, the length of each cable rack CR is, for example, 3 m, and the length of each top cover TC and bottom cover BC is, for example, 1.5 m. and two bottom covers BC are used. Additionally, six cable rack CRs are connected, forming a rack path with a total length of 18 m.

When installing a top cover TC and a bottom cover BC by installing a rack path as shown in FIG. Electrical connections were made using grounding fittings. The connection parts at that time are shown by broken ellipses, and 22 connection operations are required in total. For example, if this rack path is installed at a high location that is difficult to reach, it will be necessary to use an aerial work vehicle whose work platform can be raised and lowered. That is, conventionally, the aerial work vehicle was moved 11 times every 1.5 m (the oval position indicated by the broken line), the work platform was raised and lowered each time, and the electrical connection work of the top cover TC and the bottom cover BC was performed 22 times. It was necessary to do it.

In FIG. 7, a rectangle extending vertically from the top cover TC to the bottom cover BC indicates the cable rack grounding fitting 1 of this embodiment. One cable rack grounding fitting 1 is attached to one top cover TC and one bottom cover BC. Therefore, in the rack route shown in FIG. 7, it is necessary to attach the cable rack grounding fittings 1 at 12 locations. In addition, since the cable rack grounding fitting 1 can be attached to any position on the cover, by moving two adjacent cable rack grounding fittings 1 close together, two cable rack grounding fittings 1 can be placed at a distance that can be reached from the workbench. Two cable rack grounding fittings 1 can be attached. Therefore, when using the cable rack grounding fitting 1 of this embodiment, the aerial work vehicle is moved six times every 3 m, and the work platform is raised and lowered each time to install the cable rack grounding fitting 1. Since this is carried out 11 times, both the number of times the aerial work vehicle is moved and the number of times the cable rack grounding fitting 1 is attached can be reduced compared to the conventional method. In this way, by using the cable rack grounding fitting 1 of this embodiment, it is possible to significantly reduce the work required to electrically connect the cable rack CR to the top cover TC and the bottom cover BC. be.

As explained above, according to the cable rack grounding fitting 1 according to the present embodiment, the cable rack CR can be electrically connected to the top cover TC and the bottom cover BC, so that the cable By simply connecting only the rack CR to the ground electrode, it is possible to ground the entire cable rack CR, top cover TC, and bottom cover BC. Furthermore, in the past, adjacent covers were electrically connected to each other, so it was necessary to perform electrical connection work for the top cover and the bottom cover, respectively. On the other hand, according to the present embodiment, electrical connection between the top cover and the bottom cover can be made at the same time by simply connecting one cable rack grounding fitting 1, so that the work required for electrical connection of the cover, etc. can be significantly reduced.

Further, according to the cable rack grounding fitting 1 according to the present embodiment, the first connection portion 26, the second connection portion 27, and the third connection portion 28 are connected to the top cover TC, the bottom cover BC, and the cable rack. Since the electrical connection is made by press-welding each CR, the work can be done more easily and quickly than with a configuration in which a conductive hole is provided in the cover and a bolt is inserted into the conductive hole to make the connection. is possible. Furthermore, even if the surfaces of the cable rack CR, top cover TC, and bottom cover BC are subjected to non-conductive surface treatment to provide weather resistance, rust prevention, etc., the first connection portion Since the surface treatment can be broken by pressing 26 or the like, it is possible to reliably electrically connect the cable rack CR to the top cover TC and the bottom cover BC.

Furthermore, according to the cable rack grounding fitting 1 according to the present embodiment, the top cover side edge TC2 is sandwiched between the first pressure contact parts 261 and 262 and the first opposing part 263, and the second pressure contact part 271 , 272 and the second opposing part 273 sandwich the lower cover side edge BC2, so that the cable rack grounding fitting 1 can be easily and quickly attached to the side surfaces of the cable rack CR, the upper cover TC, and the lower cover BC. It is possible to attach it to In addition, simply screw the bolts 3, 4, and 5 into the respective screw holes 264, 274, and 282 provided in the first opposing part 263, the second opposing part 273, and the third opposing part 281 and tighten them. Since the bolts 3, 4, and 5 can be pressed against the top cover TC, bottom cover BC, and cable rack CR, the work can be done easily and quickly.

Further, according to the cable rack grounding fitting 1 according to the present embodiment, the first pressure contact parts 261, 262 and the second pressure contact parts 271, 272 bite into the surface treatment film of the top cover TC and the bottom cover BC. Since the corner portions 261a, 262a, 271a, and 272a are provided to break at the edges, it is possible to securely perform electrical connection in addition to pressure contact using the bolts 3, 4, and 5.

Furthermore, according to the cable rack grounding fitting 1 according to the present embodiment, the bending process is used to form the first press-contact parts 261, 262 and the second press-contact parts 271, 272, and the slit-shaped cut Since the corners 261a, 262a, 271a, 272a are formed by twisting the edges of the notches 2A1, 2A2, 2A3, and 2A4, there is no need to provide protrusions by blanking or punching as in the past, and it is suitable for cable racks. It is possible to reduce the number of steps for creating the grounding fitting 1. In addition, in blanking and punching, the shape of the protrusions formed may change due to wear of the mold (such as blunting of acute edges), but in the present invention, the torsion during bending is used. , the effects of mold wear, etc. can be reduced. Therefore, it is possible to stably obtain corner portions 261a, 262a, 271a, and 272a with little change in shape.

Further, according to the cable rack grounding fitting 1 according to the present embodiment, in the width direction of the parent girders CR1 and CR2, the third connection portion 28 is provided at one end side where the child girder CR3 is constructed and the rigidity is increased. , so that the parent girder CR1 will not be deformed by bringing the third connecting portion 28 into pressure contact with the parent girder CR1.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. This embodiment relates to a locking metal fitting used together with a cable rack grounding metal fitting 1 when electrically connecting a cable rack CR and a top cover TC or a bottom cover BC attached to the cable rack CR. It is.

As shown in FIG. 8, the locking metal fitting 6 has a first surface 61 and a second surface 62 formed by bending a substantially rectangular plate material so that the cross section thereof has a substantially L-shape. Further, the first surface 61 is provided with a connecting hole (connecting portion) 611 that is connected to either the first connecting portion 26 or the second connecting portion 27 of the cable rack grounding fitting 1. There is. Further, the second surface 62 is provided with a hook-shaped locking portion 621 that is locked to one end in the width direction of the master beam CR1.

The first surface 61 of the locking metal fitting 6 is inserted into the cable rack earthing metal fitting 1 so that the second surface 62 is arranged on the back side of the cable rack earthing metal fitting 1, and the second connecting part 27 The lower cover bolt 4 is inserted into the connecting hole 611 and connected to the metal fitting body 2. The tip of the first surface 61 of the locking metal fitting 6 is bent in order to come into contact with the inner surface of the cable rack earthing metal fitting 1 within the cable rack earthing metal fitting 1, and is further bent to contact the inner surface of the cable rack earthing metal fitting 1. Some parts are cut out to avoid interference.

FIG. 9 shows a state in which the cable rack CR and the top cover TC are electrically connected using the cable rack grounding fitting 1 and the locking fitting 6. The locking fitting 6 connected to the second connection part 27 of the cable rack grounding fitting 1 has a locking part 621 locked to the lower end of the main girder CR1, and the locking fitting 6 is connected to the first connection part 26 and the third connection part 26. The portion 28 electrically connects the cable rack CR and the top cover TC.

Although the case where the cable rack CR and the top cover TC are electrically connected using the cable rack grounding fitting 1 and the locking fitting 6 has been described, it is also possible to connect the cable rack CR and the bottom cover BC. An electrical connection is also possible. In this case, the locking metal fitting 6 is connected to the first connecting portion 26 of the cable rack grounding metal fitting 1. The locking fitting 6 connected to the cable rack grounding fitting 1 has a locking portion 621 locked to the upper end of the main girder CR1, and the second connecting portion 27 and the third connecting portion 28 connect the cable Rack CR and bottom cover BC are electrically connected.

Further, in this embodiment, as shown in FIG. 9, the metal fitting main body 2 and the locking metal fitting 6 are connected by the bottom cover bolts 4, and the cable rack CR is electrically connected by the rack bolts 5. However, the functions of these two bolts 4 and 5 may be combined with one bolt. Specifically, instead of the bottom cover bolt 4, a rack bolt 5, which is longer than the bottom cover bolt 4, is screwed into the second screw hole 274 of the second connection part 27, and the rack bolt 5 is screwed into the second screw hole 274 of the second connection part 27. It is inserted into the connecting hole 611 of the locking metal fitting 6 and then pressed against the side surface of the cable rack CR. As a result, the metal fitting main body 2 and the locking metal fitting 6 can be connected using one rack bolt 5, and the cable rack CR can be electrically connected, so the number of bolts used can be reduced to two. Improves work efficiency.

Note that when electrically connecting the cable rack CR and the bottom cover BC, the number of bolts used can be reduced in the same manner as described above. Specifically, instead of the top cover bolt 3, a rack bolt 5 longer than the top cover bolt 3 is screwed into the first screw hole 264 of the first connection part 26, and the rack bolt 5 is screwed into the first screw hole 264 of the first connection part 26. What is necessary is to insert it into the connecting hole 611 of the locking metal fitting 6 and then press it against the side surface of the cable rack CR.

According to this embodiment, by using the locking metal fitting 6 that can be used in combination with the cable rack grounding metal fitting 1, the cable rack CR and the top cover TC or bottom cover BC attached to the cable rack CR are electrically connected. It is possible to connect to Therefore, even if the cable rack CR has a single-sided cover, it is possible to effectively utilize the cable rack grounding fitting 1 of this embodiment without preparing another grounding fitting.

Although the embodiments of this invention have been described above, the specific configuration is not limited to the above embodiments, and even if there are changes in the design within the scope of the gist of this invention, Included in invention. For example, in order to electrically connect the cable rack grounding fitting 1 to the top cover TC and the bottom cover BC, the corner portion 261a, Although the corner portions 262a, 271a, and 272a are formed, the corner portions 261a, 262a, 271a, and 272a may be omitted if the electrical connection using the bolts 3, 4, and 5 is ensured.

In the above embodiment, in order to insert the bolts 3, 4 and 5 to the cable rack CR1, the top cover TC and the bottom cover BC, the first pressure welding parts 261, 262 and the second pressure welding parts 271, 272 are connected to each other. There was a gap between them. However, when holes are provided on the back side of the cable rack grounding fitting 1 through which the bolts 3, 4, and 5 can be inserted, the first insulation displacement parts 261, 262 and the second insulation displacement parts 271, 272 are formed integrally. may have been done.

Furthermore, in the above embodiment, when only one of the top cover TC and the bottom cover BC is attached to the cable rack CR1, the cable rack grounding fitting 1 and the locking fitting 6 are combined to make electrical connection. However, a dedicated grounding fitting may be provided. Specifically, the locking metal fitting 6 is provided integrally with the above-mentioned cable rack grounding metal fitting 1 instead of the first connection part 26 or the second connection part 27 on one end side. This eliminates the need to assemble the locking metal fittings 6 into the cable rack grounding metal fitting 1, thereby improving work efficiency.

Moreover, the cable rack grounding fitting 1 and the locking metal fitting 6 according to the present embodiment can be used for cable racks with different width dimensions of the parent girder by adjusting the length of the metal fitting body 2 and the size of the locking metal fitting 6. can also be applied.

1 Earthing fitting for cable rack 2 Fitting main body 26 First connection part 261, 262 First press-fitting part 261a, 262a Corner part 263 First opposing part 264 First screw hole 27 Second connection part 271, 272 2 pressure contact parts 271a, 272a corner parts 273 second opposing part 274 second screw hole 28 third connection part 281 third opposing part 282 third screw hole 3 top cover bolt (first bolt)
4 Bottom cover bolt (second bolt)
5 Rack bolt (third bolt)
6 Locking metal fitting 61 First surface 611 Connection hole (connection part)
62 Second surface 621 Locking part CR Cable rack CR1, CR2 Main girder CR3 Child girder TC Top cover (first cover)
TC2 Top cover side edge (first side edge)
BC Bottom cover (second cover)
BC2 Bottom cover side edge (second side edge)

Claims (7)

A ladder-like cable rack comprising a pair of elongated main girders and a plurality of child girders installed between the main girders, and a cable rack on one side of the cable rack so as to cover between the pair of main girders. For a cable rack used for a first cover attached to the first cover and a second cover attached to the other side of the cable rack opposite to the one side so as to cover between the pair of parent girders. A grounding fitting,
arranged along the width direction of the master spar that is orthogonal to the longitudinal direction of the master spar and the child spar,
a first connection part electrically connected to the first cover;
a second connection part provided at a position opposite to the first connection part and electrically connected to the second cover;
a third connecting portion provided at a connecting portion connecting the first connecting portion and the second connecting portion and electrically connected to a side surface of the parent girder;
A grounding fitting for a cable rack characterized by comprising: The first cover includes a first cover body that covers between the pair of master girders, and a first side edge that is bent so that both sides of the first cover body are along the width direction of the master girder. The second cover includes a second cover body that covers between the pair of parent girders, and a second cover body that is bent such that both sides of the second cover body are along the width direction of the parent girders. a second side edge portion;
The first connecting portion is electrically connected to the first cover by press-contacting the first side edge portion,
The second connecting portion is electrically connected to the second cover by press-contacting the second side edge portion,
The third connecting portion is electrically connected to the side surface of the parent girder by press-contacting it.
The grounding fitting for a cable rack according to claim 1. The first connection portion includes a first pressure contact portion inserted between the side surface of the parent girder and the first side edge portion, and a first pressure contact portion inserted between the side surface of the parent girder and the first side edge portion, and a A first opposing part facing the pressure contact part, a first screw hole provided in the first opposing part, and a first opposing part that is screwed into the first screw hole and press-connected to the first side edge part. and a first bolt that presses the first pressure contact portion to the inner surface side of the first side edge portion,
The second connection part includes a second pressure contact part inserted between the side surface of the parent girder and the second side edge part, and a second pressure contact part inserted between the side surface of the main girder and the second side edge part, and a second facing part that faces the pressure contact part; a second screw hole provided in the second facing part; and a second facing part that is screwed into the second screw hole to be pressed against the second side edge part. and a second bolt for press-contacting the second press-contact portion to the inner surface side of the second side edge portion,
The third connecting portion is screwed into a third opposing portion facing a side surface of the parent girder, a third screw hole provided in the third opposing portion, and the third screw hole. and a third bolt that presses against the side surface of the parent girder.
The grounding fitting for a cable rack according to claim 2. The first pressure contact portion includes a corner portion that bites into and breaks the surface treatment film of the first side edge portion,
The second pressure contact portion includes a corner portion that bites into and breaks the surface treatment film of the second side edge portion.
The grounding fitting for a cable rack according to claim 3. The first press-contact part and the second press-contact part are formed by bending a plate material provided with a slit-shaped notch along the slit direction at the notch part,
The corner portions of the first pressure contact portion and the second pressure contact portion are formed by twisting the edges of the notch.
The grounding fitting for a cable rack according to claim 4. In the cable rack, the child girder is installed on one end side in the width direction of the parent girder,
The third connection part is arranged at one end side where the child girder is constructed in the width direction of the parent girder,
The grounding fitting for a cable rack according to claim 2. comprising a locking metal fitting used in combination when electrically connecting the cable rack and the first cover or the second cover attached to the cable rack,
The locking metal fitting is formed by bending a substantially rectangular plate material so that the cross section becomes substantially L-shaped to form a first surface and a second surface, and the first connection is formed on the first surface. A connecting part is provided to be connected to either one of the part and the second connecting part, and a locking part to be locked to one end in the width direction of the main girder is provided on the second surface. ,
When only the first cover is attached to the cable rack, the locking fitting connected to the second connection part is locked to the main girder, and the first connection part and electrically connecting the cable rack and the first cover by the third connection part;
When only the second cover is attached to the cable rack, the locking fitting connected to the first connection part is locked to the main girder, and the second connection part and electrically connecting the cable rack and the second cover by the third connection part;
A ground connection device for a cable rack according to claim 1.