JP7650753B2 - Seismic isolation free access floor structure - Google Patents

Description

The present invention relates to a seismically isolated free access floor structure in which a buffer plate is provided to close the gap between the floor panels of the seismically isolated section and the floor panels of the non-seismically isolated section.

Free access floors, in which multiple floor panels are supported horizontally at a specified height above the foundation floor by multiple support legs installed on the foundation floor, forming a second floor surface above the foundation floor, are widely used as the floor structure for rooms such as server rooms where a large amount of important IT equipment is installed. However, free access floors with seismic isolation structures have been used as an earthquake countermeasure for such free access floors (see Patent Document 1).

Figures 10 and 11 are figures to be referred to in order to explain a conventional free access floor 2 equipped with such a seismic isolation structure.

As shown in FIG. 11, a conventional free access floor 2 includes a floor panel 4 of a non-seismic isolation section 2a installed on the wall side of a room 1, a floor panel 4 of a seismic isolation section 2b installed in the center of the room 1, and a buffer plate 12 installed to close the gap 2c formed between the non-seismic isolation section 2a and the seismic isolation section 2b.

In the non-seismically isolated section 2a, as shown on the left side of Figure 12, multiple floor panels 4 are supported horizontally at a predetermined height above the foundation floor 3 by multiple support legs 6 installed on the foundation floor 3.

At this time, each support leg 6 is fixed to the foundation floor 3 using anchor bolts, adhesives, etc., so that the floor panel 4 of the non-seismically isolated portion 2a is fixed to the foundation floor 3 and cannot move horizontally when an earthquake or other event occurs and causes horizontal displacement of the building.

On the other hand, in the seismic isolation section 2b, as shown on the right side of Figure 12, a seismic isolation frame 10 was installed on the foundation floor 3, and multiple floor panels 4 were supported horizontally at a predetermined height above the foundation floor 3 by multiple seismic isolation section support legs 8 installed on the seismic isolation frame 10.

The seismic isolation frame 10 is installed on the foundation floor 3 so as to be supported by the seismic isolation device 10a provided at the bottom thereof, and the seismic isolation section support leg 8 is formed with a structure similar to that of the support leg 6 and is fixed to the seismic isolation frame 10 using bolts, nuts, etc.

The seismic isolation device 10a allows the floor panel 4 of the seismic isolation section 2b to be detached from the foundation floor 3 and move horizontally relative to the foundation floor 3 when an earthquake or other event occurs and causes horizontal displacement in the building.

The floor panel 4 of the seismic isolation section 2b is positioned at a predetermined horizontal distance from the floor panel 4 of the non-seismic isolation section 2a so as not to come into contact with the floor panel 4 of the non-seismic isolation section 2a in the event of an earthquake. As a result, a gap 2c is formed between the seismic isolation section 2b and the non-seismic isolation section 2a, opening with a predetermined opening width in the horizontal direction, and a buffer plate 12 is provided to close this gap 2c.

As shown in FIG. 12, the buffer plate 12 is formed in a generally plate-like shape with a predetermined thickness dimension, and the horizontal end of the buffer plate 12 on the seismic isolation section 2b side (right side in the figure) is attached to the end of the floor panel 4 of the seismic isolation section 2b via an attachment member 13 provided on the seismic isolation section support leg 8 that supports the floor panel 4 of the seismic isolation section 2b, and the horizontal end of the buffer plate 12 on the non-seismic isolation section 2a side (left side in the figure) is positioned so as to be overlapped on the floor panel 4 of the non-seismic isolation section 2a.

As a result, when an earthquake or other event occurs and causes horizontal displacement of the building, the buffer plate 12 is able to move horizontally relative to the foundation floor 3 together with the floor panel 4 of the seismic isolation section 2b, with the horizontal end of the buffer plate 12 on the non-seismic isolation section 2a side always positioned above the floor panel 4 of the non-seismic isolation section 2a.

In this way, in a conventional free access floor 2 equipped with a seismic isolation structure, when an earthquake or the like occurs and horizontal displacement occurs in the building, the floor panel 4 of the non-seismically isolated section 2a and the floor panel 4 of the seismically isolated section 2b are prevented from coming into contact with each other, and the buffer plate 12 can close the gap 2c between the non-seismically isolated section 2a and the seismically isolated section 2b.

Japanese Utility Model Application Publication No. 7-42835 JP 2012-149429 A

However, conventional free access floors with seismic isolation structures as described above have the problem of increased manufacturing costs for the buffer plates 12 and construction costs for installation work.

In other words, in order to reduce the unevenness of the upper surface of the free access floor 2 after construction, it is desirable for the thickness of the buffer plate 12 to be as thin as possible, provided that it has the required strength.

As a result, the strength of the buffer plate 12 must be designed in a different procedure from that of the floor panel 4, a different material must be selected from that of the floor panel 4, and the buffer plate 12 must be manufactured in a different process from that of the floor panel 4, which could lead to an increase in the manufacturing costs of the buffer plate 12.

In addition, in a conventional free access floor equipped with the seismic isolation structure described above, the buffer plate 12 is attached to the floor panel 4 of the seismic isolation section 2b by placing its end on the inside of the mounting member 13. Therefore, if the buffer plate 12 jumps up during an earthquake, there is a risk that the end of the buffer plate 12 on the seismic isolation section 2b side may come off the mounting member 13.

In response to this, a configuration has been proposed in which the end of the buffer plate on the seismic isolation side fits into and engages with a mounting member provided on the support leg of the seismic isolation section that supports the floor panel of the seismic isolation section (see Patent Document 2). However, in this case, the structure of the mounting member becomes complicated, which may increase the manufacturing costs of the mounting member and complicate the installation work.

In view of the above problems, the present invention aims to provide a seismic isolation free access floor structure that reduces the manufacturing costs of the buffer plate and allows the buffer plate to be easily attached to the floor panel at low cost and with sufficient strength, thereby reducing the construction costs of the free access floor.

In order to solve the above problems, the seismic isolation free access floor structure of the present invention is as follows:
A seismic isolation free access floor structure comprising a floor panel of a non-seismically isolated portion fixed to a foundation floor, a floor panel of a seismically isolated portion provided so as to be movable horizontally relative to the foundation floor, and a buffer plate provided so as to close a gap formed between the non-seismically isolated portion and the seismically isolated portion,
The buffer plate includes a substantially plate-shaped main body, a first attachment member provided so as to extend in an elongated manner in the length direction of the main body along a base end portion in the width direction of the main body, and a connecting member connecting the main body and the first attachment member,
The main body and the first mounting member are connected by the connecting member so as to be rotatable with each other about a central axis extending in a longitudinal direction of the main body,
The base end of the main body is attached to the seismic isolation section by fixing the first mounting member to a second mounting member provided on a panel support portion of a seismic isolation section support leg that supports the floor panel of the seismic isolation section, and by supporting the bottom of the base end of the main body by the second mounting member.

In addition, the seismic isolation free access floor structure of the present invention is as follows:
The connecting member is a hinge member including a pair of substantially plate-shaped wing portions and a shaft portion that rotatably connects the pair of wing portions to each other,
The main body and the first mounting member are connected so as to be able to rotate relatively to each other around the shaft portion by fixing the pair of wing portions to the side of the base end of the main body and the underside of the first mounting member, respectively.

In addition, the seismic isolation free access floor structure of the present invention is as follows:
The second mounting member includes a buffer plate support portion extending horizontally along an upper surface of the panel support portion of the seismic isolation unit support leg, and a buffer plate mounting portion extending substantially parallel to the buffer plate support portion at a predetermined interval above the buffer plate support portion,
the first mounting member is fixed to the buffer plate mounting portion of the second mounting member,
The bottom of the base end of the main body is placed on the buffer plate support portion of the second mounting member.

In addition, the seismic isolation free access floor structure of the present invention is as follows:
The main body of the shock absorber plate is manufactured by processing the floor panel.

According to the seismic isolation free access floor structure of the present invention,
A seismic isolation free access floor structure comprising a floor panel of a non-seismically isolated portion fixed to a foundation floor, a floor panel of a seismically isolated portion provided so as to be movable horizontally relative to the foundation floor, and a buffer plate provided so as to close a gap formed between the non-seismically isolated portion and the seismically isolated portion,
The buffer plate includes a substantially plate-shaped main body, a first attachment member provided so as to extend in an elongated manner in the length direction of the main body along a base end portion in the width direction of the main body, and a connecting member connecting the main body and the first attachment member,
The main body and the first mounting member are connected by the connecting member so as to be rotatable with each other about a central axis extending in a longitudinal direction of the main body,
The base end of the main body is attached to the seismic isolation section by the first mounting member being fixed to a second mounting member provided on a panel support portion of a support leg of the seismic isolation section that supports the floor panel of the seismic isolation section, and the bottom of the base end of the main body is supported by the second mounting member.
This reduces the manufacturing costs of the buffer plate and also enables the buffer plate to be easily attached to the floor panel at low cost and with sufficient strength, thereby reducing the construction costs of the free access floor.

FIG. 2 is a side view of a free access floor 22 according to one embodiment of the present invention. 2A and 2B are diagrams showing a floor panel 24 in the free access floor 22 shown in FIG. 1, with FIG. 2A being a bottom view and FIG. 2B being a side view. 2 is a plan view of the buffer plate 34 in the free access floor 22 shown in FIG. 1. 2 is a side view of the buffer plate 34 in the free access floor 22 shown in FIG. 1. 5A is an enlarged cross-sectional view taken along line AA in FIG. 3, and FIG. 5B is an enlarged cross-sectional view taken along line BB in FIG. 3. FIG. 2 is an enlarged side view showing the periphery of the base end of the buffer plate 34 in the free access floor 22 shown in FIG. 1 . 2 is an enlarged side view showing the periphery of the tip of the buffer plate 34 in the free access floor 22 shown in FIG. 1 . 2 is a schematic side view for explaining the behavior of the free access floor 22 shown in FIG. 1 when an earthquake occurs. FIG. 2 is a schematic side view for explaining the behavior of the free access floor 22 shown in FIG. 1 when an earthquake occurs. FIG. FIG. 11 is a plan view showing another embodiment of the buffer plate 34, that is, a buffer plate 34 for four corners. 1 is a schematic plan view showing a room 1 in which a conventional free access floor 2 having a seismic isolation structure is installed. FIG. 12 is a side view of the free access floor 2 shown in FIG.

Below, we will explain in detail the form for implementing the seismic isolation free access floor structure of the present invention with reference to the drawings.

Figures 1 to 9 are figures to be referred to in order to explain a free access floor 22 equipped with a seismic isolation structure according to one embodiment of the present invention. Note that parts similar to those of the conventional free access floor 2 equipped with a seismic isolation structure shown in Figures 11 and 12 will be described with the same reference numerals, with some exceptions.

As shown in FIG. 1, the free access floor 22 according to this embodiment, like the conventional free access floor 2 (see FIG. 11), comprises a floor panel 24 of a non-seismic isolation section 22a laid on the wall side of the room 1, a floor panel 24 of a seismic isolation section 22b laid in the center of the room 1, and a buffer plate 34 arranged to close the gap 22c formed between the non-seismic isolation section 22a and the seismic isolation section 22b.

In the non-seismically isolated section 22a, as shown on the left side of Figure 1, multiple floor panels 24 are supported horizontally at a predetermined height above the foundation floor 3 by multiple support legs 26 installed on the foundation floor 3.

As shown in Figures 2(a) and (b), the floor panel 24 has a flat upper surface and a substantially plate-like flat plate portion 24a formed in a substantially square planar shape, and a number of ribs 24b that are integrally formed with the flat plate portion 24a, with height portions protruding downward from the rear surface of the flat plate portion 24a and length portions extending in a substantially lattice pattern in the vertical and horizontal directions along the rear surface of the flat plate portion 24a.

As shown in FIG. 2(a), bolt holes 24c are formed at the four corners of the floor panel 24, penetrating the flat plate portion 24a in the thickness direction (perpendicular to the plane of the drawing).

Such a floor panel 24 is formed, for example, as a die-cast product using an aluminum alloy as its material, by integrally molding the flat plate portion 24a and the ribs 24b.

As shown in FIG. 1, the support leg 26 has a leg portion 27 installed on the foundation floor 3 and an adjustment stand 28 provided on the upper part of the leg portion 27.

The leg 27 of the support leg 26 has a substantially plate-shaped base plate 27a that is arranged substantially horizontally along the foundation floor 3, a support pillar 27b that is erected so as to extend vertically from the center of the upper surface of the base plate 27a, and a male threaded portion 27c that is provided at the upper end of the support pillar 27b.

The adjustment base 28 of the support leg 26 is formed in a generally cylindrical shape with a central axis extending vertically, and is equipped with a boss portion 28a having a female thread formed on the inner peripheral surface of the central hole, and a generally disk-shaped panel support portion 28b having a flat upper surface and extending radially outward in the horizontal direction from the upper end of the boss portion 28a.

Above the panel support portion 28b, a panel fixing portion 28c is formed in a generally cylindrical shape with a central axis extending vertically and with a female thread formed on the inner peripheral surface of the central hole. The panel fixing portion 28c is provided integrally with the panel support portion 28b or detachably attached to the panel support portion 28b.

The male threaded portion 27c of the leg 27 is screwed from below into the female threaded portion of the boss portion 28a of the adjustment table 28. In this state, the height position of the panel support portion 28b of the support leg 26 from the foundation floor 3 can be adjusted by rotating the adjustment table 28 relative to the leg 27 along the helical trajectory of the screw of the male threaded portion 27c.

In the non-seismically isolated portion 22a of the free access floor 22, as shown in FIG. 1, multiple such support legs 26 are installed on the foundation floor 3 on the wall side of the room 1 (left side in the figure), and multiple floor panels 24 supported by these support legs 26 are arranged side by side along the wall of the room 1 with their four sides horizontally adjacent to each other (see FIG. 11).

At this time, each support leg 26 is installed on the foundation floor 3 so that it cannot move horizontally relative to the foundation floor 3 by fixing the base plate 27a to the foundation floor 3 using anchor bolts, adhesives, etc.

The floor panels 24 are supported horizontally at a predetermined height above the foundation floor 3 by placing up to four floor panels 24 so that their four corners are butted against each other, with the four corners of the butted floor panels 24 placed on the panel support parts 28b of one support leg 26 and the other four corners of the floor panels 24 placed on the panel support parts 28b of another support leg 26.

The panel fixing bolt 25 is inserted through the bolt hole 24c of the floor panel 24 from the top side of the floor panel 24, and its tip is screwed into the female thread of the panel fixing portion 28c provided on the panel support portion 28b of the support leg 26, thereby fixing the floor panel 24 to the support leg 26.

Therefore, the floor panel 24 of the non-seismically isolated portion 22a is fixed to the foundation floor 3 so that it cannot move horizontally when an earthquake or other event occurs and causes horizontal displacement in the building.

On the other hand, in the seismic isolation section 22b, as shown on the right side of Figure 1, a seismic isolation frame 30 is installed on the foundation floor 3, and multiple floor panels 24 are supported horizontally at a predetermined height above the foundation floor 3 by multiple seismic isolation section support legs 32 installed on the seismic isolation frame 30.

As shown in FIG. 1, the seismic isolation support leg 32 is formed with the same configuration (legs and adjustment base) as the support leg 26, but the overall height dimension is smaller than that of the support leg 26.

The seismic isolation frame 30 is formed by combining multiple beam members 30a with an H-shaped (or I-shaped) cross section that extend horizontally in a roughly lattice pattern in the vertical and horizontal directions.

A seismic isolation device 30b is provided at the bottom of the seismic isolation frame 30, and the seismic isolation frame 30 is installed on the foundation floor 3 so as to be supported by this seismic isolation device 30b.

In the seismic isolation section 22b of the free access floor 22, as shown in FIG. 1, such a seismic isolation frame 30 is installed on the foundation floor 3, and multiple seismic isolation section support legs 32 are installed on the seismic isolation frame 30, and multiple floor panels 24 supported by these seismic isolation section support legs 32 are arranged in the center of the room 1 with their four sides horizontally adjacent to each other (see FIG. 11).

At this time, each of the seismic isolation section support legs 32 is fixed onto the seismic isolation frame 30 using bolts and nuts, etc., and each of the floor panels 24, like the floor panels 24 of the non-seismic isolation section 22a, has its four corners placed on the panel support parts 32a of the seismic isolation section support legs 32 and is fixed to the seismic isolation section support legs 32 using panel fixing bolts 25.

The seismic isolation device 30b has a number of rolling spheres at the part that comes into contact with the foundation floor 3, and the seismic isolation frame 30 is placed on the foundation floor 3 so that it can move horizontally relative to the foundation floor 3 as these spheres roll.

In addition, a coil spring (not shown) and an oil damper (not shown) are provided to connect the foundation floor 3 and the seismic isolation frame 30 horizontally, and the restoring force of the coil spring and the damping force of the oil damper return the horizontal position of the seismic isolation frame 30 to a predetermined initial position.

As a result, the floor panel 24 of the seismic isolation section 22b is configured to be detached from the foundation floor 3 and move horizontally relative to the foundation floor 3 when an earthquake or other event occurs and causes horizontal displacement of the building.

In this way, the behavior of the floor panel 24 of the seismic isolation section 22b differs from that of the floor panel 24 of the non-seismic isolation section 22a when horizontal displacement occurs in the building during an earthquake, so that the floor panel 24 of the seismic isolation section 22b does not come into contact with the floor panel 24 of the non-seismic isolation section 22a when it moves, the floor panel 24 of the seismic isolation section 22b is positioned horizontally at a predetermined distance away from the floor panel 24 of the non-seismic isolation section 22a.

As a result, a gap 22c with a predetermined opening width in the horizontal direction (left-right direction in FIG. 1) is formed between the seismic isolation section 22b and the non-seismic isolation section 22a along the outer periphery of the floor panel 24 of the seismic isolation section 22b, and a buffer plate 34 is provided to close this gap 22c.

As shown in FIG. 3, the buffer plate 34 includes a substantially plate-like main body 35 with a substantially rectangular planar shape, an attachment member 36 (first attachment member) provided along the base end (the end on the right side in the figure) of the main body 35 in the width direction (left-right direction in the figure), and two hinge members 37 (connecting members) that connect the main body 35 and the attachment member 36.

As shown in Figures 3 and 4, the main body 35 of the buffer plate 34 has a flat upper surface and a substantially plate-like flat plate portion 35a formed in a substantially square planar shape, and a number of ribs 35b that are formed integrally with the flat plate portion 35a, with height portions protruding downward from the rear surface of the flat plate portion 35a and length portions extending in a substantially lattice pattern in the vertical and horizontal directions along the rear surface of the flat plate portion 35a.

As shown in FIG. 4, at the tip (the end on the left side in the figure) of the width direction (the left-right direction in the figure) of the main body 35, the height dimension of the rib 35b (and the thickness dimension of the flat plate portion 35a) gradually decreases toward the tip in the width direction of the main body 35, thereby forming an inclined portion 35c formed so that the bottom of the main body 35 is inclined toward the top surface of the main body 35.

Such a main body 35 is formed, for example, as a die-cast product using an aluminum alloy as its material, by integrally molding the flat plate 35a and the ribs 35b.

As shown in FIG. 1, the main body 35 has a thickness dimension (vertical direction in the figure) that is approximately the same as the thickness dimension of the floor panel 24, a width dimension (horizontal direction in the figure) that is slightly smaller than the opening width of the gap 22c formed between the floor panel 24 of the seismic isolation section 22b and the floor panel 24 of the non-seismic isolation section 22a, and a length dimension perpendicular to the width direction (perpendicular to the paper surface of the figure) that is approximately the same as the length dimension of one side of the outer portion of the floor panel 24.

In this way, the main body 35 has a configuration in common with the floor panel 24 shown in Figure 2 in terms of its material, size, and part of its structure.

As shown in Figures 3 and 4, the mounting member 36 (first mounting member) of the buffer plate 34 is elongated in the length direction of the main body 35 (vertical direction in Figure 3), and is formed in a generally square rod shape with a generally rectangular cross section perpendicular to the length direction (see Figure 4), and its length dimension is formed to be approximately the same as the length dimension of the main body 35.

As shown in FIG. 3, bolt holes 36a are formed at three points along the length of the mounting member 36, i.e., near the center and both ends of the mounting member 36 in the longitudinal direction, as shown in FIG. 5(a), penetrating the mounting member 36 in the thickness direction (the vertical direction in the figure).

As shown in FIG. 3, at two points along the length of the mounting member 36, i.e., at positions closer to the center than the two bolt holes 36a formed near both ends of the mounting member 36, recesses 36b are formed so that the entire width direction (left-right direction in the figure) of the bottom surface of the mounting member 36 is recessed toward the top surface of the mounting member 36 over a predetermined width dimension in the length direction of the mounting member 36 (perpendicular to the paper surface of the figure), as shown in FIG. 5(b).

As shown in FIG. 3, such an attachment member 36 is arranged so that its length extends in the length direction (up and down direction in the figure) of the main body 35 along the base end (the end on the right side in the figure) of the width direction (left and right direction in the figure) of the main body 35.

At this time, as shown in FIG. 5(b), the upper surface of the main body 35 and the upper surface of the mounting member 36 are positioned on the same plane, and the mounting member 36 is positioned slightly outward in the horizontal direction (to the right in the figure) from the base end (the end on the right in the figure) of the main body 35 in the width direction (left-right direction in the figure).

The main body 35 and the mounting member 36 are connected to each other by hinge members 37 at two points along the length of the mounting member 36, that is, at the recesses 36b of the mounting member 36 that are formed closer to the center than the two bolt holes 36a formed near both ends of the mounting member 36.

That is, as shown in FIG. 5(b), the hinge member 37 comprises a pair of generally plate-like wing portions 37a, 37b with tube portions at their ends, and a shaft portion 37c that is inserted continuously through the tube portions of the wing portions 37a, 37b to rotatably connect them to each other. One wing portion 37a of the hinge member 37 is arranged along the side surface of the base end portion (the end portion on the right side in the figure) in the width direction (left-right direction in the figure) of the main body portion 35 and is fixed to the main body portion 35 by a flat head screw and nut 37d, etc., and the other wing portion 37b of the hinge member 37 is arranged inside the recess portion 36b on the underside of the mounting member 36 and is fixed to the mounting member 36 by a flat head screw 37e.

As a result, the main body 35 and the mounting member 36 can rotate relative to each other around the shaft 37c of the hinge member 37, which extends in the longitudinal direction of the main body 35 (and in the longitudinal direction of the mounting member 36).

As shown in FIG. 6, the base end in the width direction of the main body 35 of such a buffer plate 34 is attached to the seismic isolation section 22b by fixing the mounting member 36 to a mounting member (second mounting member) consisting of a bracket 38 and an L-shaped member 40 provided on the upper surface of the panel support portion 32a of the seismic isolation section support leg 32 that is located closest to the gap 22c (left side in the figure) among the multiple seismic isolation section support legs 32 that support the floor panel 24 of the seismic isolation section 22b.

As shown in FIG. 6, the bracket 38 is provided with a substantially plate-shaped buffer plate support portion 38a extending horizontally (left-right direction in the figure), a substantially plate-shaped connecting portion 38b bending at a substantially right angle from the end of the buffer plate support portion 38a on the right side in the figure and extending upward, and a substantially plate-shaped buffer plate attachment portion 38c bending at a substantially right angle from the upper end of the connecting portion 38b toward the buffer plate support portion 38a (left side in the figure) and extending substantially parallel to the buffer plate support portion 38a at a predetermined distance above the buffer plate support portion 38a, and is formed with a predetermined width dimension in the direction perpendicular to the plane of the figure.

The horizontal length dimension (left-right direction in FIG. 6) of the buffer plate mounting portion 38c is formed to be slightly smaller than the width dimension (left-right direction in FIG. 6) of the mounting member 36 of the buffer plate 34, and the horizontal length dimension of the buffer plate support portion 38a is formed to be sufficiently larger than the horizontal length dimension of the buffer plate mounting portion 38c.

As shown in FIG. 6, the L-shaped member 40 has a substantially plate-shaped bottom plate portion 40a that extends horizontally (left-right direction in the figure) and a substantially plate-shaped side plate portion 40b that bends at a substantially right angle from the end of the bottom plate portion 40a on the right side in the figure and extends upward, and is formed with a predetermined width dimension in the direction perpendicular to the paper surface of the figure.

The vertical height dimension of the side plate portion 40b is formed to be approximately the same as the thickness dimension of the floor panel 24.

The L-shaped member 40 is placed on the panel support part 32a of the seismic isolation section support leg 32 so that the bottom plate part 40a contacts along the upper surface of the panel support part 32a and the right side surface of the side plate part 40b contacts along the left side surface of the floor panel 24 of the seismic isolation section 22b as shown in FIG. 6, and the bottom plate part 40a is fixed to the panel support part 32a of the seismic isolation section support leg 32 by the screw 40c.

The bracket 38 is placed on the L-shaped member 40 so that the buffer plate support portion 38a overlaps the bottom plate portion 40a of the L-shaped member 40 and the connecting portion 38b overlaps the left side of the side plate portion 40b of the L-shaped member 40 in the figure, and the connecting portion 38b is fixed to the side plate portion 40b of the L-shaped member 40 by a flat head screw and nut 38d.

As shown in FIG. 6, the mounting member 36 of the buffer plate 34 is placed on the buffer plate mounting portion 38c of the bracket 38 so as to fit along the outer periphery of the outermost floor panel 24 of the seismic isolation section 22b that faces the gap 22c, and the right side of the mounting member 36 is positioned so as to contact the left side of the side plate portion 40b of the L-shaped member 40.

Then, the fixing bolt 39 is inserted into the bolt hole 36a of the mounting member 36 from the upper side of the mounting member 36, and its tip passes through the buffer plate mounting portion 38c and is screwed into the nut member 38e provided on the lower side of the buffer plate mounting portion 38c, thereby fixing the mounting member 36 of the buffer plate 34 to the buffer plate mounting portion 38c of the bracket 38.

At this time, the upper surfaces of the main body 35 and mounting member 36 of the buffer plate 34 are positioned so as to be flush with the upper surface of the floor panel 24 of the seismic isolation section 22b.

The bottom of the base end (the end on the right side in FIG. 6) of the main body 35 of the buffer plate 34 is positioned so as to rest on the buffer plate support portion 38a of the mounting member 38.

As a result, the main body 35 of the buffer plate 34 can rotate in the longitudinal direction of the main body 35 and the mounting member 36, i.e., clockwise in FIG. 6, around the central axis of the shaft 37c of the hinge member 37 that extends along the outer periphery of the outermost floor panel 24 of the seismic isolation section 22b facing the gap 22c. However, since the bottom of the base end of the main body 35 is supported and locked by the buffer plate support part 38a, the bottom plate part 40a of the mounting member 40 below it, and the panel support part 32a of the seismic isolation section support leg 32, it cannot rotate in the opposite direction (counterclockwise in FIG. 6).

On the other hand, as shown in FIG. 7, the widthwise tip of the main body 35 of the buffer plate 34 is supported by a buffer plate support leg 42 installed on the foundation floor 3.

As shown in FIG. 1, the buffer plate support leg 42 is formed with the same structure (leg and adjustment stand) as the support leg 26, and is installed in the gap 22c on the foundation floor 3 near the non-seismically isolated portion 22a (left side in the figure), and a support member 44 is provided on the panel support portion 42a.

As shown in FIG. 7, the support member 44 has a generally plate-shaped flat portion 44a that extends horizontally (left-right direction in the figure) and a generally plate-shaped inclined portion 44b that bends from the end of the flat portion 44a on the right side in the figure and extends toward the lower right in the figure, and is formed with a predetermined width dimension in the direction perpendicular to the plane of the figure.

The support member 44 is placed on the panel support part 42a of the buffer plate support leg 42 so that the flat plate part 44a is in contact with the upper surface of the panel support part 42a and the inclined part 44b is inclined toward the seismic isolation part 22b, and the flat plate part 44a is fixed to the panel support part 42a of the buffer plate support leg 42 by the screw 44c.

In addition, a receiving plate member 46 is provided on the panel support portion 28b of the support leg 26 that is located closest to the gap 22c (right side in the figure) among the multiple support legs 26 that support the floor panel 24 of the non-seismically isolated portion 22a.

As shown in FIG. 7, the receiving plate member 46 has a substantially plate-shaped bottom plate portion 46a extending horizontally (left-right direction in the figure), a substantially plate-shaped side plate portion 46b bending at a substantially right angle from the right end of the bottom plate portion 46a in the figure and extending upward, and a substantially plate-shaped inclined portion 46c bending from the upper end of the side plate portion 46b and extending toward the lower right in the figure, and is formed with a predetermined width dimension in the direction perpendicular to the paper surface of the figure.

The inclination angle of the inclined portion 46c is formed to be approximately the same as the inclination angle of the inclined portion 35c of the main body portion 35 of the buffer plate 34.

The receiving plate member 46 is arranged so that the bottom plate portion 46a is sandwiched between the panel support portion 28b and the floor panel 24 placed on it along the upper surface of the panel support portion 28b, and the left side surface of the side plate portion 46b in the figure contacts the right side surface of the floor panel 24 of the non-seismic isolation portion 22a in the figure, and is arranged on the panel support portion 28b of the support leg 26 so that the inclined portion 46b is inclined toward the seismic isolation portion 22b, and the bottom plate portion 46a is fixed to the panel support portion 28b of the support leg 26 by the screw 46d.

The widthwise tip of the main body 35 of the buffer plate 34 is placed on the support member 44 provided on the panel support portion 42a of the buffer plate support leg 42 so that the upper surface of the main body 35 is located on the same plane as the upper surface of the floor panel 24 of the non-seismic isolation section 22a, as shown in FIG. 7, and the inclined portion 35c of the main body 35 is positioned close to the inclined portion 46b of the receiving plate member 46 provided on the panel support portion 28b of the support leg 26 that supports the floor panel 24 of the non-seismic isolation section 22a, and along the inclined surface.

As a result, most of the weight of the widthwise tip of the main body 35 of the buffer plate 34 is supported by the buffer plate support legs 42.

In this way, the base end of the main body 35 in the width direction of the buffer plate 34 is supported by the seismic isolation section support legs 32, and the tip end of the main body 35 in the width direction is supported by the buffer plate support legs 42, so that the main body 35 is supported with sufficient support strength to close the gap 22c between the non-seismic isolation section 22a and the seismic isolation section 22b.

Next, based on Figures 8 and 9, we will explain the behavior of the buffer plate 34 on the free access floor 22 when horizontal displacement occurs in the building due to an earthquake or the like.

First, as shown in FIG. 8, when a horizontal displacement occurs in the building due to an earthquake or the like, and the floor panel 24 of the seismic isolation section 22b moves closer to the floor panel 24 of the non-seismic isolation section 22a, the inclined portion 35c of the tip end (left end in the figure) of the main body 35 of the buffer plate 34 comes into contact with the inclined portion 46c of the receiving plate member 46, and moves in the upper left direction in the figure along the inclination of the inclined portion 46c.

As a result, the main body 35 of the buffer plate 34 rotates clockwise in the figure around the shaft 37c of the hinge member 37, while the tip of the main body 35 slides over the inclined portion 46c of the receiving plate member 46, and the floor panel of the non-seismically isolated portion 22a moves so that it rides up onto 24.

Next, as shown in FIG. 9, when a horizontal displacement occurs in the building due to an earthquake or the like, causing the floor panel 24 of the seismic isolation section 22b to move away from the floor panel 24 of the non-seismic isolation section 22a, the tip (left end in the figure) of the main body 35 of the buffer plate 34 slides over the flat plate section 44a of the support member 44 and moves to the right in the figure, separating it from the panel support section 42a of the buffer plate support leg 42.

At this time, the main body 35 of the buffer plate 34 is locked by being supported at the bottom of its base end (the right end in FIG. 9) by the buffer plate support portion 38a of the bracket 38, etc., so that the main body 35 cannot rotate counterclockwise in FIG. 9 around the shaft portion 37c of the hinge member 37, and the height position of the tip of the main body 35 does not decrease.

When the displacement caused by an earthquake or the like stops, the floor panel 24 of the seismic isolation section 22b returns to its predetermined initial position due to the restoring force of the coil spring installed between the foundation floor 3 and the seismic isolation frame 30 and the damping force of the oil damper, and accordingly, the tip end (left end in the figure) of the main body 35 of the buffer plate 34 moves to its initial position above the panel support part 42a of the buffer plate support leg 42, as shown in Figure 1.

At this time, the bracket 38 supporting the main body 35 of the buffer plate 34 is elastically deformed by the weight of the buffer plate 34, etc., so that even if the height position of the tip of the main body 35 is somewhat lowered, when the tip of the main body 35 approaches the panel support part 42a of the buffer plate support leg 42, the inclined part 35c of the tip comes into contact with the inclined part 44b of the support member 44, slides over the inclined part 44b, and rides up onto the panel support part 42a of the buffer plate support leg 42.

In this way, in the case of the free access floor 22, when an earthquake or the like occurs and horizontal displacement occurs in the building, the floor panel 24 of the non-seismic isolation section 22a and the floor panel 24 of the seismic isolation section 22b are prevented from coming into contact with each other, and the buffer plate 34 can close the gap 22c between the floor panel 24 of the non-seismic isolation section 22a and the floor panel 24 of the seismic isolation section 22b.

By using the seismic isolation free access floor structure according to this embodiment, the manufacturing costs of the buffer plate 34 can be reduced.

In other words, as described above, the material and some of the size and structure of the main body 35 of the buffer plate 34 are the same as those of the floor panel 24 shown in FIG. 2, so that the floor panel 24, its manufacturing process, and some of the strength calculation procedures can be reused to manufacture the buffer plate 34.

Furthermore, the mounting member 36 can be easily made by processing a long, thin, rectangular bar-shaped member, the hinge member 37 can be a commercially available product, the bracket 38, L-shaped member 40, support member 44, and receiving plate member 46 can be easily made by bending a roughly rectangular plate-shaped member at a predetermined position, and the buffer plate support leg 38 can be made by reusing the existing support leg 26.

In this way, the buffer plate 34 and the parts used to attach it are both easy to manufacture and secure, which helps reduce the manufacturing costs of the buffer plate 34.

In addition, by using the seismic isolation free access floor structure according to this embodiment, the buffer plate 34 can be easily attached with sufficient strength.

In other words, the mounting member 36 of the buffer plate 34 is firmly fixed to the buffer plate mounting portion 38c of the bracket 38 using the fixing bolt 39, so that even if the buffer plate 34 moves upward, it is possible to prevent the buffer plate 34 from coming off the floor panel 24 of the seismic isolation section 22b.

The buffer plate 34 can be attached using existing means such as flat head screws and bolts, so no special tools or jigs are required and it can be easily installed.

In this way, the seismic isolation free access floor structure of this embodiment reduces the manufacturing costs of the buffer plate and allows the buffer plate to be easily attached to the floor panel at low cost and with sufficient strength, thereby reducing the construction costs of the free access floor.

In addition, according to the seismic isolation free access floor structure of this embodiment, the mounting member 36 of the buffer plate 34 is disposed between the main body 35 of the buffer plate 34 and the floor panel 24 of the seismic isolation section 22b, so that the members (brackets 38 and L-shaped members 40) used to mount the buffer plate 34 can be hidden when viewed from the top side of the floor panel 24, and a gap can be prevented from being created between the main body 35 and the floor panel 24.

In addition, with the seismic isolation free access floor structure of this embodiment, the main body 35 of the buffer plate 34 is made from the same material as the floor panel 24, which improves the sense of unity in appearance between the floor panel 24 and the buffer plate 34 when viewed from the top side of the floor panel 24.

The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the invention to achieve its objectives.

For example, in the seismic isolation free access floor structure in the above embodiment, as shown in FIG. 3, the planar shape of the main body 35 of the buffer plate 34 is formed into a substantially rectangular shape, but the planar shape of the main body 35 is not limited to such a configuration, and the planar shape of the main body 35 may be formed into a shape other than a substantially rectangular shape.

That is, for example, when installing the buffer plates 34 at the four corners of the gap 22c (see FIG. 11) that is formed in a substantially rectangular shape along the outer periphery of the seismic isolation section 22b, the buffer plates 34 may be formed in a substantially trapezoidal planar shape of the main body section 35, as shown in FIG. 10, such that the lower side of the four sides that make up the outer shape of the main body section 35 extends in a substantially 45-degree diagonal direction (from the upper right to the lower left in the figure) from the base end (the end on the right side in the figure) of the main body section 35 to the tip end (the end on the left side in the figure).

In addition, in the seismic isolation free access floor structure in the above embodiment, the length dimension of the main body 35 (vertical direction in FIG. 3) is formed to be approximately the same as the length dimension of one side of the outer part of one floor panel 24, but the length dimension of the main body 35 is not limited to such a configuration. For example, a long and narrow gap that would be blocked by multiple buffer plates 34 shown in FIG. 3 lined up in the length direction may be blocked by a single buffer plate formed so that the length dimension of the main body is an integer multiple, such as two or three times, of the length dimension of one side of the floor panel 24.

In addition, in the seismic isolation free access floor structure in the above embodiment, the free access floor 22 uses a substantially plate-shaped flat portion 24a with ribs 24b molded integrally on the back surface, but the floor panel 24 is not limited to such a configuration. For example, a floor panel may be used in which a reinforcing member is placed in the internal space of a main body formed into a substantially box shape by pressing.

In addition, in the seismic isolation free access floor structure in the above embodiment, the widthwise end of the main body 35 of the buffer plate 34 is supported by the buffer plate support legs 40 installed on the foundation floor 3, but the support means for the end of the main body 35 is not limited to such a configuration, and the end of the main body 35 may be supported by any means as long as it has sufficient support strength.

In addition, in the seismic isolation free access floor structure in the above embodiment, the seismic isolation frame 30 is formed by combining beam members 30a with an H-shaped (or I-shaped) cross section in a roughly lattice pattern, but the configuration of the seismic isolation frame 30 is not limited to this, and the seismic isolation frame 30 may be formed by combining members other than beam members 30a with an H-shaped (or I-shaped) cross section, such as square pipes.

REFERENCE SIGNS LIST 1 room 2 free access floor 2a non-seismic isolation section 2b seismic isolation section 2c gap 3 foundation floor 4 floor panel 6 support leg 8 seismic isolation section support leg 10 seismic isolation frame 10a seismic isolation device 12 buffer plate 13 mounting member 22 free access floor 22a non-seismic isolation section 22b seismic isolation section 22c gap 24 floor panel 24a flat plate section 24b rib 24c bolt hole 25 panel fixing bolt 26 support leg 27 leg section 27a base plate 27b support column 27c male thread section 28 adjustment stand 28a boss section 28b panel support section 28c panel fixing section 30 seismic isolation frame 30a beam member 30b seismic isolation device 32 seismic isolation section support leg 32a panel support section 34 Buffer plate 35 Main body 35a Flat plate 35b Rib 35c Inclined portion 36 Mounting member 36a Bolt hole 36b Recess 37 Hinge member 37a, 37b Wing portion 37c Shaft 37d Flat head screw and nut 37e Flat head screw 38 Bracket 38a Buffer plate support portion 38b Connecting portion 38c Buffer plate mounting portion 38d Flat head screw and nut 38e Nut member 39 Fixing bolt 40 L-shaped member 40a Bottom plate portion 40b Side plate portion 40c Screw 42 Buffer plate support leg 42a Panel support portion 44 Support member 44a Flat plate portion 44b Inclined portion 44c Screw 46 Receiving plate member 46a Bottom plate portion 46b Side plate portion 46c Inclined portion 46d Screw

Claims (4)

A seismic isolation free access floor structure comprising a floor panel of a non-seismically isolated portion fixed to a foundation floor, a floor panel of a seismically isolated portion provided so as to be movable horizontally relative to the foundation floor, and a buffer plate provided so as to close a gap formed between the non-seismically isolated portion and the seismically isolated portion,
The buffer plate includes a substantially plate-shaped main body, a first attachment member provided so as to extend in an elongated manner in the length direction of the main body along a base end portion in the width direction of the main body, and a connecting member connecting the main body and the first attachment member,
The main body and the first mounting member are connected by the connecting member so as to be rotatable with each other about a central axis extending in a longitudinal direction of the main body,
A seismic isolation free access floor structure characterized in that the base end of the main body is attached to the seismic isolation section by the first mounting member being fixed to a second mounting member provided on a panel support portion of a seismic isolation section support leg that supports the floor panel of the seismic isolation section, and the bottom of the base end of the main body being supported by the second mounting member. the connecting member is a hinge member including a pair of wing portions and a shaft portion that rotatably connects the pair of wing portions to each other,
The seismic isolation free access floor structure according to claim 1, characterized in that the main body and the first mounting member are connected so as to be able to rotate relatively to each other around the shaft portion by fixing the pair of blade portions to the side surface of the base end of the main body and the underside of the first mounting member, respectively. The second mounting member includes a buffer plate support portion extending horizontally along an upper surface of the panel support portion of the seismic isolation unit support leg, and a buffer plate mounting portion extending substantially parallel to the buffer plate support portion at a predetermined interval above the buffer plate support portion,
the first mounting member is fixed to the buffer plate mounting portion of the second mounting member,
The seismic isolation free access floor structure according to claim 1 or 2, characterized in that the bottom of the base end of the main body is placed on the buffer plate support part of the second mounting member. The seismic isolation free access floor structure according to any one of claims 1 to 3, wherein the main body of the buffer plate is manufactured by processing the floor panel.

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