JP7463088B2 - Earthquake-proof pull box - Google Patents

Description

The present invention relates to a seismic isolation pull box for pulling various wiring cables, such as communication cables such as optical cables and electrical wiring, from the ground or other such places into a building.

Conventionally, in a seismically isolated building, when wiring cables such as communication lines and electrical wiring are pulled into the building from underground or utility poles, the edges of the cable rack are cut on the ground side and the building side, and the wiring cables are exposed on the top of the plate installed between them and connected in a coiled shape. Therefore, even if the wiring cables are subjected to a load due to lateral shaking during an earthquake, etc., the coiled excess length allows the wiring cables to displace and follow the load, absorbing the load.
For example, in the typical wiring equipment shown in Figures 7(a) and (b), wiring cables 102 such as electric wires and communication lines that penetrate a side wall 101 of a foundation 100 laid on the ground are coiled around the excess part 102a on the bottom plate of the foundation 100, and the other end of the wiring cable 102 is supported by a hanging bracket 104 or a rack provided on the building base 103 (see non-patent document 1).

CERA-DESIGN Architectural Structural Design, "Seismic Isolation Design Notes," "2010.04 Edition, Appendix 4, "Appendix 4. Seismic Isolation Material Specifications Example," Appendix 4-3, "4. Electricity, Telephone, etc. Connection" [Retrieved November 20, 2019], Internet (http://cera.world.coocan.jp/)

However, in the wiring equipment described in Non-Patent Document 1, the excess length 102a of the coiled wiring cable 102 is exposed on the bottom plate of the foundation 100, which makes it prone to deterioration and damage, and also poses safety issues. In addition, when vibrations occur due to an earthquake or the like, the wiring cable 102 may get caught on a foreign object and not move in response to the vibrations, resulting in breakage or damage.

The present invention was made in consideration of these problems, and aims to provide a seismic isolation pull box that can protect the wiring cable by preventing it from being exposed to the outside, and can also absorb the load placed on the wiring cable due to vibrations during earthquakes, etc.

The seismic isolation pull box according to the present invention comprises a first box fixed to the ground and having a first hole through which a distribution cable is inserted, and a second box fixed to a building that sways horizontally relative to the ground, arranged opposite the first box, and having a second hole through which the distribution cable is inserted, wherein the opening directions of the openings of the first box and the second box are vertical, the distribution cable is stored with an excess portion in the internal space formed by the first box and the second box, and the first box and the second box are capable of vibrating relative to each other.
According to the present invention, the wiring cable is stored in the internal space of the first box and the second box with an excess length wound in coils or the like, which protects the wiring cable from the outside and increases safety. In addition, even if the first box and the second box shift relatively laterally due to vibrations caused by an earthquake or the like, the excess length can be extended to accommodate the displacement, thereby preventing cuts or damage to the wiring cable.

In addition, it is preferable that a hanging support portion for hanging and supporting the distribution cable is provided in the second box opposite the second hole portion.
Since a hanging support part for the distribution cable is provided inside the second box facing the second hole part, even if the first box and the second box shift sideways relative to each other due to an earthquake or the like, the distribution cable can be prevented from bending and becoming pinched between the first box and the second box, resulting in cut or damage.

A seal member may be provided at an end of the opening where the first box and the second box abut against each other.
By sealing the ends of the first box and the second box with a seal member, foreign matter will not enter from the outside and tampering will not occur.

It is also preferable that a first pipe having a distribution cable inserted therethrough is connected to the first hole, and a second pipe having a distribution cable inserted therethrough is connected to the second hole.
Safety is increased because the first and second pipes protect not only the inside of the seismic isolation pull box but also the external wiring cables.

The seismic isolation pull box of the present invention provides high safety by storing and protecting the wiring cable within the internal space formed by the first box and the second box. Furthermore, even if the first box and the second box storing the wiring cable vibrate and shift sideways due to an earthquake or other event, causing a load such as pulling on the wiring cable, the wiring cable will displace and the excess length can absorb the load.

FIG. 2 is a perspective view of a seismic isolation pull box according to an embodiment of the present invention. This is an oblique view of the seismic isolation pull box with the upper box and the lower box shifted. This is an explanatory diagram of the seismic isolation pull box installed between the ground and a building. 1A and 1B are explanatory diagrams showing the upper and lower boxes of a seismic isolation pull box misaligned in the horizontal direction. 6A, 6B, and 6C are explanatory diagrams showing a state in which the upper box and the lower box of the first comparative example are misaligned. 13A and 13B are explanatory diagrams showing a state in which the upper box and the lower box of the second comparative example are misaligned. FIG. 1A is a cross-sectional view of a conventional wiring facility, and FIG. 1B is a diagram showing an excess length of a distribution cable.

Hereinafter, a seismic isolation pull box according to an embodiment of the present invention will be described with reference to the accompanying drawings.
1 to 4 show a seismic isolation pull box 1 according to an embodiment. The seismic isolation pull box 1 shown in Fig. 1 includes a lower box 2 and an upper box 3, which are arranged vertically. The lower box 2 has a lower surface 6 and four side surfaces 7a, 7b, 7c, and 7d made of steel plates fixed to a metal frame having a rectangular parallelepiped shape, for example, and has an opening 8 on the upper surface. The lower surface 6 of the lower box 2 is fixed to a foundation 4 on the ground G via a seismic isolation layer 5. The seismic isolation layer 5 has a structure in which multiple layers of elastic material such as rubber are laminated, and reduces the transmission of vibrations from the ground G to the lower box 2 during an earthquake or the like.

The upper box 3 is connected to the base 11 of the building 10, and has a top surface 12 and four side surfaces 13a, 13b, 13c, and 13d made of steel plates fixed to a rectangular parallelepiped metal frame, for example, and has an opening 14 at the bottom. Moreover, the top surface 12 is fixed to the base 11 of the building 10. The building 10 is a seismically isolated building connected to the ground G via a seismic isolation layer (not shown).
In the normal state of the seismic isolation pull box 1, a gasket 15 is provided as a sealing member around one of the sides 7a, 7b, 7c, and 7d that form the opening 8 of the lower box 2 and the sides 13a, 13b, 13c, and 13d that form the opening 14 of the upper box 3, for example, around the entire circumference of the end of each side 7a, 7b, 7c, and 7d of the lower box 2.

As a result, under normal conditions, the gasket 15 of the lower box 2 and the lower end of each side surface 13a to 13d of the upper box 3 are in contact with each other, and the opening 8 of the lower box 2 and the opening 14 of the upper box 3 are liquid-tightly sealed. Furthermore, during an earthquake or the like, the lower box 2 vibrates in conjunction with the ground G and the seismic isolation layer 5, and the upper box 3 vibrates in conjunction with the building 10, so they are able to slide horizontally relative to each other. During vibration, the lower box 2 and upper box 3 are not affected by each other's movements.

2, one or more, for example, six, first holes 17 are formed in one side surface 7a of the lower box 2, and one end of a first pipe 18 made of, for example, metal is connected to each of the first holes 17. The first holes 17 provided in one side surface 7a are formed, for example, in a row in the longitudinal direction of the side surface 7a, but the arrangement of the first holes 17 can be formed arbitrarily.
A distribution cable 19, such as a communication line such as an optical fiber, an electric wire, or a telephone line, is inserted into the first tube 18. The other end of the first tube 18 is connected to, for example, another tube or a closure provided in a manhole (not shown). In this embodiment, for example, one distribution cable 19 is inserted into each first tube 18, but a plurality of cables may be inserted in a bundle or separately.

1, the other side surface 13c of the upper box 3 facing the one side surface 7a of the lower box 2 has second holes 21 formed therein in the same number as the first holes 17, and one end of a second pipe body 22 made of metal, for example, is connected to each second hole 21. The second holes 21 provided in the other side surface 13c are formed, for example, in a row in the longitudinal direction of the side surface 13c, but the arrangement of the second holes 21 can be formed arbitrarily.
The wiring cable 19 is inserted into the second pipe 22. The other end of the second pipe 22 is connected to, for example, communication equipment in a server room in the building 10. The wiring cable 19 provided on the outside of the seismic isolation pull box 1 is all covered and protected by the first pipe 18 and the second pipe 22.

The wiring cable 19 inserted through the first pipe 18 of the lower box 2 and the second pipe 22 of the upper box 3 is stored in a coiled state within the closed internal space of the lower box 2 and upper box 3, as shown in Fig. 3. The coiled portion of the wiring cable 19 is referred to as an excess portion 19a, and is preferably held within the lower box 2.
In the event of an earthquake or the like, as shown in Figures 4(a) and (b), it is assumed that the ground G, the seismic isolation layer 5, and the building 10 will vibrate in the horizontal direction, causing the lower box 2 and the upper box 3 to shift position. Even in such a case, the length of the wiring cable 19 in the internal space of the seismic isolation pull box 1 is set to a length that allows the surplus part 19a to be displaced and maintained in a bent state. Therefore, in the event of an earthquake, the surplus part 19a of the wiring cable 19 can shorten or lengthen to absorb vibrations.

Moreover, inside the upper box 3, a plurality of hanging supports 24 hang down from the top surface 12 at positions facing each second pipe 22. Each hanging support 24 has, for example, a hook-shaped or ring-shaped support portion for supporting the wiring cable 19. Moreover, each hanging support 24 is provided at a position facing each second hole 21 of the side surface 13c, and each wiring cable 19 is arranged in a substantially straight line from the hanging support 24 to the second pipe 22, thereby preventing the wiring cables 19 from becoming entangled with each other or getting caught between the lower box 2 and the upper box 3.
In the seismic isolation pull box 1 of this embodiment, the horizontal relative displacement (shift) between the seismic isolation layer 5 and the building 10 during an earthquake is set to a maximum of 700 mm, for example, and the vertical and horizontal lengths of the lower box 2 and upper box 3 are set to approximately twice that, that is, 1500 mm, for example.

The seismic isolation pull box 1 according to this embodiment has the above-mentioned configuration, and its operation will now be described.
1 and 3, in the seismic isolation pull box 1, the lower box 2 and the upper box 3 are arranged one above the other without any misalignment, and are arranged liquid-tightly via a gasket 15. The distribution cable 19 is covered and protected by the first pipe 18, the second pipe 22 and the seismic isolation pull box 1 between the seismic isolation layer 5 of the ground G and the base 11 of the building 10. In this state, electric current, communication signals, etc. can be transmitted and received between communication devices in a server room in the building 10 and the outside via the distribution cable 19.

Next, when an earthquake or the like occurs, the vibration of the building 10 lags behind the vibration of the ground G, causing a misalignment between the relative movement of the seismic isolation layer 5 of the ground G and the relative movement of the base 11 of the building 10. The lower box 2 is linked to the vibration of the seismic isolation layer 5 of the ground G, and the upper box 3 is linked to the vibration of the building 10, causing a horizontal positional misalignment between the lower box 2 and the upper box 3 of the seismic isolation pull box 1.
4(a), when the upper box 3 moves relative to the lower box 2 in a direction away from the first pipe 18, the wiring cable 19 is pulled in the internal space of the seismic isolation pull box 1. Even in this case, the wiring cable 19 in the internal space of the seismic isolation pull box 1 is maintained in a state where the coiling of the excess length 19a is not completely eliminated and the bending is small and the deformation is small. Moreover, since the wiring cable 19 is supported by the hanging support part 24 at a position facing the second pipe 22, the wiring cable 19 can be prevented from hanging down and being pinched between the lower box 2 and the upper box 3.

4(b), when the upper box 3 moves relative to the lower box 2 in a direction approaching the first pipe 18, the excess part 19a of the wiring cable 19 is further bent in the internal space of the seismic isolation pull box 1. Moreover, since the wiring cable 19 is supported by the hanging support part 24 at an opposing position near the second pipe 22, the wiring cable 19 is displaced in the lower box 2.
Then, when the vibrations of the ground G and the building 10 subside, the lower box 2 and the upper box 3 return to their original overlapping positions as shown in Fig. 3 due to the restoring force of the building 10. Therefore, the slack portion 19a of the distribution cable 19 is kept in a coiled state within the internal space of the seismic isolation pull box 1.

Next, a comparative example related to the seismic isolation pull box 1 according to this embodiment will be described with reference to FIGS.
First, in the seismic isolation pull box 1 according to this embodiment, a case where the hanging support parts 24 are not provided inside the upper box 3 will be described with reference to Fig. 5. When the hanging support parts 24 are not provided, the wiring cable 19 is held in a coiled state with the excess length part 19a inside the lower box 2 and upper box 3, which do not shift in position, as shown in Fig. 5(a) in a state where there is no earthquake.

As shown in FIG. 5(b), when an earthquake occurs and the lower box 2 and the upper box 3 move relatively away from each other, resulting in a positional shift of approximately 700 mm, part of the wiring cable 19 is stretched and hangs down in a roughly U-shape between the side surface 7c of the lower box 2 and the side surface 13c of the upper box 3, with one side supported by the second pipe body 22. Then, as shown in FIG. 5(c), when the lower box 2 and the upper box 3 move relatively closer to each other, the bent U-shaped part of the wiring cable 19 may be pinched between the side surfaces 7c and 13c and damaged or cut. To avoid such problems, it is preferable to install a hanging support part 24.

Next, a case where the size of the lower box 2 and the upper box 3 is such that the estimated displacement during an earthquake is, for example, about 700 mm will be described with reference to FIG.
In this case, when there is no earthquake, the distribution cable 19 is held in a coiled state by the excess length 19a inside the lower box 2 and upper box 3, which do not shift position, as shown in Figure 6 (a). In the vicinity of the second pipe 22, the distribution cable 19 is supported by a hanging support part 24 hanging down from the top surface 12 of the upper box 3 and is inserted into the second pipe 22.
Next, as shown in Figure 6 (b), if an earthquake occurs and the lower box 2 and the upper box 3 move relative to each other in the direction away from each other and become misaligned, the wiring cable 19 may become pinched between the side surface 7c of the lower box 2 and the side surface 13a of the upper box 3, and may be cut or damaged.
Therefore, in order to avoid such problems, it is preferable that the vertical and horizontal dimensions of the lower box 2 and the upper box 3 are made larger than the displacement of 700 mm during an earthquake.

As described above, according to the seismic isolation pull box 1 of this embodiment, the wiring cable 19 is surrounded by the lower box 2 and the upper box 3, which separate the wiring cable 19 between the seismic isolation layer 5 of the ground G and the base 11 of the building 10, and the wiring cable 19 is coiled with an extra length 19a to provide some slack. Therefore, the wiring cable 19 can be covered and protected by the seismic isolation pull box 1, and can be protected from damage or cutting even if the lower box 2 and the upper box 3 are displaced horizontally due to an earthquake or the like. Moreover, when the earthquake subsides, the lower box 2 and the upper box 3 return to their original overlapping positions, and the wiring cable 19 can be restored to the coiled state with the extra length 19a.
In addition, since the wiring cable 19 is supported by the hanging support part 24 hanging down near the second pipe body 22 of the upper box 3, the wiring cable 19 can be prevented from bending and being pinched even if the lower box 2 and the upper box 3 move relative to each other due to an earthquake or the like.

In addition, the vertical and horizontal sizes of the lower box 2 and the upper box 3 are made larger than the maximum displacement of 700 mm expected during an earthquake, so that even if the lower box 2 and the upper box 3 move relative to each other in opposite directions during an earthquake, the lower box 2 and the upper box 3 will not shift to the extent that they eliminate overlap, thereby preventing the wiring cable 19 from being cut or damaged.
Moreover, a gasket 15 is provided at one end of each of the openings 8, 14 of the lower box 2 and the upper box 3 to provide a liquid-tight seal. Furthermore, the first pipe 18 and the second pipe 22 are connected to the first hole 17 and the second hole 21 of the seismic isolation pull box 1, respectively, and the wiring cable 19 is inserted inside. Therefore, the wiring cable 19 is not exposed to the outside, and is protected from intrusion of foreign objects such as insects and tampering, thereby improving safety. Furthermore, even if rainwater infiltrates between the foundation 4 of the ground G and the base 11 of the building 10 during a torrential rain or a typhoon, the wiring cable 19 can be prevented from coming into contact with the rainwater.

The present invention is not limited to the seismic isolation pull box 1 according to the embodiment described above, and appropriate modifications and substitutions are possible without departing from the gist of the present invention, all of which are included in the present invention. Below, we will explain modified examples of the present invention, but the same reference numerals will be used to designate parts and components that are the same as or similar to the embodiment described above, and explanations will be omitted.

For example, in the seismic isolation pull box 1 according to the above-mentioned embodiment, the first hole 17 for connecting the first pipe 18 is provided on one side surface 7a of the lower box 2, and the second hole 21 for connecting the second pipe 22 is provided on the opposing side surface 13c of the upper box 3, through which the wiring cable 19 is inserted. However, the arrangement of the first hole 17 of the lower box 2 for connecting the first pipe 18 and the second hole 21 of the upper box 3 for connecting the second pipe 22 can be selected from any of the sides 7a to 7d and sides 13a to 13d. For example, the first pipe 18 and the second pipe 22 may be connected to the respective sides 7a to 7d and sides 13a to 13d so as to be perpendicular to each other, or may be connected to the sides 7a to 7d and sides 13a to 13d on the same side.
Furthermore, the lower box 2 and the upper box 3 of the seismic isolation pull box 1 are not limited to a rectangular box shape, but may have any suitable shape, such as a cylindrical shape or a polygonal tubular shape.

In the above-described embodiment, the first pipe 18 and the second pipe 22 are provided outside the seismic isolation pull box 1 to cover the wiring cable 19 outside the seismic isolation pull box 1 as well. However, the wiring cable 19 provided outside the seismic isolation pull box 1 does not have to be covered with the first pipe 18 and the second pipe 22, etc., which are metal pipes or the like.
In addition, a plurality of seismic isolation pull boxes 1 may be arranged on the seismic isolation layer 5 on the foundation 4, and a plurality of wiring cables 19 may be connected between the manholes and the building 10, respectively.
In the present invention, the lower box 2 is included in the first box, and the upper box 3 is included in the second box.

Reference Signs List 1: seismic isolation pull box 2: lower box 3: upper box 4: foundations 7a, 7b, 7c, 7d, 13a, 13b, 13c, 13d: side 8, 14: opening 10: building 11: base 12: upper surface 15: gasket 17: first hole 18: first pipe 19: distribution cable 21: second hole 22: second pipe 24: hanging support G: ground

Claims (4)

a first box fixed to the ground and having a first hole through which a distribution cable is inserted;
a second box that is fixed to a building that horizontally swings relative to the ground and is disposed opposite the first box and has a second hole through which the distribution cable is inserted;
Equipped with
A seismic isolation pull box characterized in that the opening direction of the openings of the first box and the second box is vertical, the distribution cable is stored with an excess portion within the internal space formed by the first box and the second box, and the first box and the second box are capable of vibrating relative to each other. a first box fixed to the ground and having a first hole through which a distribution cable is inserted;
a second box fixed to the building and disposed opposite the first box, the second box having a second hole through which the distribution cable is inserted;
the distribution cable is housed in an internal space formed by the first box and the second box with a surplus portion, and the first box and the second box are capable of vibrating relative to each other;
A seismic isolation pull box in which a hanging support part for hanging and supporting the distribution cable is provided in the second box and faces the second hole part. a first box fixed to the ground and having a first hole through which a distribution cable is inserted;
a second box fixed to the building and disposed opposite the first box, the second box having a second hole through which the distribution cable is inserted;
the distribution cable is housed in an internal space formed by the first box and the second box with a surplus portion, and the first box and the second box are capable of vibrating relative to each other;
A seismic isolation pull box in which a sealing member is provided at the end of the opening where the first box and the second box abut. A seismic isolation pull box according to any one of claims 1 to 3, in which a first pipe body through which the wiring cable is inserted is connected to the first hole portion, and a second pipe body through which the wiring cable is inserted is connected to the second hole portion.

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