JP6084794B2 - Base-isolated floor structure - Google Patents

Description

  The present invention relates to a base-isolated floor structure that is used for a floor structure such as a free access floor and performs a base-isolating operation against vibrations and displacement of a building caused by an earthquake or the like.

  As a conventional base-isolated floor structure, as shown in FIG. 12, there is a base-isolated floor structure 2 in which a flat foundation floor surface 3 is formed on a concrete slab and is arranged on the foundation floor surface 3. In this seismic isolation floor structure 2, the ball bearing 4 is provided so as to be horizontally movable with respect to the foundation floor surface 3. It is possible to prevent transmission directly to the floor plate 6 fixed to the floor, a free access floor disposed on the floor plate 6 or the like (see Patent Document 1).

  The ball bearing 4 of the conventional seismic isolation floor structure 2 has a vertical cross section between the convex spherical surface portion 10a formed on the ball seat 10 and the concave spherical surface portion 12a formed on the ball guide 12, as shown in FIG. And a gap S formed in an annular shape in a horizontal cross section (not shown) is provided so that the gap S can be guided so as to circulate and roll the ball body 8 passing through the gap S. It was.

  And on the upper surface 12b of the ball guide 12 in which the clearance S between the ball bearings 4 is provided, the flat floor plate 6 is disposed with the lower surface 6b in contact therewith. Then, the ball guide 12 and the floor board 6 are fixed to each other by fastening the male screw portion of the bolt 14 and the female screw portion 12c of the ball guide 12 with screws.

  A free access floor (not shown) is placed on the upper surface 6a of the floor board 6 and is fixed by a fixing means (not shown).

  When the ball bearing 4 moves horizontally with respect to the foundation floor surface 3, the conventional seismic isolation floor structure 2 as described above is positioned on the opposite side of the bottom side 10b of the ball seat 10 from the side where the horizontal movement proceeds. The ball body 8 that has been moved enters the gap S and circulates and rolls, and the ball body 8 that has been positioned on the side of the horizontal movement moves toward the side opposite to the side of the movement. It was.

  For this reason, when the ball bearing 4 is horizontally moved slightly upward along the foundation floor surface 3, the many ball bodies 8 follow the horizontal movement and circulate and roll. However, by operating the ball body 8 in this way, the floor board 6 can freely move on the base floor surface 3 in any direction within a substantially horizontal plane.

  In addition, the conventional seismic isolation floor structure 2 is supported on the foundation floor surface 3 via a large number of ball bodies 8, and each of the ball bodies 8 can exert a supporting force. The vertical load that can be supported by one can be increased.

JP 2000-266115 A

  However, the conventional seismic isolation floor structure 2 has a structure in which a plurality of ball bearings 4 are arranged in contact with the floor board 6 and are fixed below the floor board 6, so that they are not flat on the foundation floor surface 3. When there is a portion where a surface (an inclined surface or an uneven surface) is formed, there is a problem that it is difficult to ground all of the ball bodies 8 of the plurality of ball bearings 4 to the foundation floor surface 3.

  And when there is a portion where the uneven surface is formed on the foundation floor surface 3, only the ball bodies 8 of some ball bearings 4 out of the plurality of ball bearings 4 are in contact with the foundation floor surface 3. It is effective that the vibration and displacement in the horizontal direction of the building caused by an earthquake or the like is directly transmitted as it is to the floor board 6 fixed on the ball bearing 4 or the free access floor arranged on the floor board 6. In other words, there is a problem that it is not possible to effectively perform seismic isolation operation against horizontal vibration and displacement of the building caused by an earthquake or the like.

  Further, as means for solving the above problems, the foundation floor surface 3 is formed as a smooth surface without a non-land surface, or the number of ball bearings 4 fixed under the floor plate 6 is increased to form a non-land surface. Even if a ball bearing 4 that cannot perform seismic isolation operation occurs opposite to the foundation floor surface 3, the number of ball bearings 4 that can perform seismic isolation operation is supplemented instead of such ball bearing 4. However, there has been a problem that these methods require a great deal of labor and cost.

  Therefore, in view of the above problems, the present invention is simple in structure, can reduce the material cost and manufacturing cost, and even if there is a portion where the uneven surface is formed on the foundation floor surface, It is an object of the present invention to provide a seismic isolation floor structure that can effectively perform a seismic isolation operation against horizontal vibration and displacement of a building caused by an earthquake or the like.

In order to solve the above problems, the seismic isolation floor structure according to the present invention is
In the seismic isolation floor structure having a base isolation frame having a plurality of frames and a plurality of base isolation support parts for supporting the base isolation frame,
The seismic isolation support portion includes a ball bearing placed on a foundation floor, a plate-like member disposed above the ball bearing, and one end of the plate-like member fixed to the plate-like member. A support bar member projecting further downward,
The ball bearing is in contact with the one end portion of the support bar member so as to be tiltable.

Moreover, the seismic isolation floor structure according to the present invention is:
A convex spherical surface portion or a chamfered portion is formed at the tip of the one end portion of the support bar member.

Moreover, the seismic isolation floor structure according to the present invention is:
The seismic isolation support part is inserted into a through hole formed in the plate-like member connected to the seismic isolation frame with one end fixed to the ball bearing and the other end extending upward. An engagement bar member,
The other end of the engaging Gobo member, which said base floor and in response to changes in the spacing of the plate-like member, characterized in that it disengaged from or the upper surface on the upper surface of the plate-like member It is.

Moreover, the seismic isolation floor structure according to the present invention is:
The seismic isolation support part includes a connecting member that connects the frames arranged so that their ends face each other, and a base isolation leg part placed on the foundation floor surface,
The connecting member has a rising plate portion formed so as to rise upward between the frames in which the respective end portions are opposed to each other,
The seismic isolation leg portion is arranged below the raised plate portion.

According to such a base-isolated floor structure of the present invention,
In the seismic isolation floor structure having a base isolation frame having a plurality of frames and a plurality of base isolation support parts for supporting the base isolation frame,
The seismic isolation support portion includes a ball bearing placed on a foundation floor, a plate-like member disposed above the ball bearing, and one end of the plate-like member fixed to the plate-like member. A support bar member projecting further downward,
The ball bearing is in contact with the one end portion of the support bar member so as to be tiltable,
The structure of the seismic isolation floor structure is simple, and material costs and manufacturing costs can be reduced, and even if there is a uneven surface on the foundation floor surface, Seismic isolation can be performed effectively against horizontal vibration and displacement.

It is a partially broken side view which shows the base isolation floor structure 40 which concerns on one embodiment of this invention. FIG. 3 is a top view of a wide range of the base isolation floor structure 40 showing a plurality of base isolation support parts 44 by reducing the base isolation floor structure 40 shown in FIG. 1. It is a top view of the seismic isolation floor structure 40 shown in FIG. 6 is a top view of a connecting member 52. FIG. It is a side view of the connection member 52 shown in FIG. It is a side view of the seismic isolation support part 44 shown excluding the connection member 52. FIG. It is a side view which shows the state which fixed the plate-shaped member 54 and the support bar member 56 mutually. FIG. 8 is a partial cross-sectional bottom view of the plate-like member 54 and the support bar member 56 shown in FIG. 7. It is a figure which shows the ball bearing 60, Comprising: It is AA arrow sectional drawing of the ball bearing 60 shown in FIG. FIG. 10 is a top view of the ball bearing 60 shown in FIG. 9. It is the seismic isolation support part 44 shown except the connection member 52 similarly to FIG. 6, Comprising: It is a side view which shows the state mounted on the inclined foundation floor surface 41. FIG. It is side surface sectional drawing which shows the conventional seismic isolation floor structure.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the seismic isolation floor structure which concerns on this invention is demonstrated concretely based on drawing.

  FIG. 1 to FIG. 11 are diagrams that are referred to in order to describe a seismic isolation floor structure 40 according to an embodiment of the present invention.

  The seismic isolation frame 42 of the base isolation floor structure 40 according to the present embodiment includes a frame 46, a cover 48, and a connecting frame 50 as shown in FIG. 2, and as shown in FIG. It is arranged away from the upper side.

  And the seismic isolation support part 44 of the seismic isolation floor structure 40 mainly has the connection member 52, the plate-shaped member 54, the support bar member 56, the volt | bolt 58 (engagement bar member), and the ball bearing 60, as shown in FIG. Are provided on the foundation floor 41 and support the seismic isolation frame 42 from below.

  Here, the other components excluding the connecting member 52 from the seismic isolation support portion 44, that is, the plate member 54, the support bar member 56, the bolt 58, and the ball bearing 60 are collectively referred to as a seismic isolation leg portion.

  As shown in FIG. 2, the seismic isolation frame 42 has a plurality of frames 46 arranged so that their length directions (left and right directions in the figure) are substantially parallel to each other, and their length direction and width direction (up and down in the figure). (Direction).

  As shown in FIG. 3, the frame 46 is formed in the shape of a square cylinder having a hollow portion 46 a, and the two frames 46 that are adjacent in the length direction of each of the frames 46 have a cover 48 and a connecting member 52. Sandwiched between the flat plate portions 52a, the opening end portions of each other are arranged to face each other.

  The cross section of the cover 48 is formed in a U-shape with the lower part close to the foundation floor 41 opened, and as shown in FIGS. The three frames 46 are arranged so as to cover and overlap the three outer surfaces of the opening ends facing each other.

  The connecting frame 50 is arranged between the sides of the cover 48 that extends in the left-right direction in FIG. 2 and is arranged in parallel to each other so that the length direction thereof is substantially perpendicular to the length direction of the frame 46. Yes.

  As shown in FIG. 3, the connection frame 50 is formed in a rectangular tube shape having a hollow portion 50 a, and the two connection frames 50 that are adjacent in the length direction are flat plate portions 52 a of the connection member 52. It is fixed on the top, and the opening end portions of each other are arranged facing each other across the cover 48 in the horizontal direction.

  As shown in FIG. 4, the connecting member 52 has cutout portions 52d formed at the four corners of the flat plate portion 52a having a substantially square shape, and the four side portions extending outward from the cutout portion 52d are: It is formed in a bent plate portion 52e (see FIG. 5) that is bent substantially perpendicularly toward the back side of the drawing.

  Twelve screw holes 52c are formed in the flat plate portion 52a of the connecting member 52 along the bent plate portion 52e.

  Two long holes 52f each having a length in the left-right direction in FIG. 4 are formed at two positions in the central portion of the flat plate portion 52a of the connecting member 52, and are separated from each other in the vertical direction in FIG. . Then, the portion of the flat plate portion 52a sandwiched between the two long holes 52f rises upward (upward in FIG. 4) from the upper surface 52b of the flat plate portion 52a by a press or the like, as shown in FIG. A rising plate portion 52h having two inclined portions 52g and an upper surface 52i substantially parallel to the upper surface 52b of the flat plate portion 52a is formed.

  As shown in FIG. 4, the rising plate portion 52h of the connecting member 52 is formed with a through hole 52j that passes through the central portion thereof, and four through holes are provided so as to surround the through hole 52j. 52k is formed.

  As shown in FIG. 1, the frame 46 is formed with through holes 46 b penetrating the upper plate portion and the lower plate portion in the vicinity of the opening end portion of the frame 46. Further, the cover 48 has a through hole 48a at a position where it overlaps the upper through hole 46b in the drawing when the open end portions of the frame 46 are covered.

  In the frame 46 and the cover 48, the male screw portion of the bolt 47 is inserted through the through holes 46 b and 48 a (see FIG. 3), and the tip portion of the male screw portion is screwed into the screw hole 52 c of the connecting member 52. Thus, the flat plate portion 52a of the connecting member 52 is fixed. The connecting frame 50 is also fixed to the flat plate portion 52a of the connecting member 52 in substantially the same manner.

  As shown in FIGS. 1 and 3, the male thread portion 56a of the support rod member 56 is inserted into the through hole 52j (see FIG. 4) of the raised plate portion 52h, and the nut 62 is halfway along the length of the male thread portion 56a. Is fixed to the rising plate portion 52h of the connecting member 52 (see FIG. 4).

  Here, since the support rod member 56 is integrally fixed to the plate-like member 54, the connecting member 52 is connected to the lower surface 52m of the raised plate portion 52h (see FIG. 5) on the upper surface 54a of the plate-like member 54. The plate-like member 54 is fixed in a state where the contact is made.

  As shown in FIG. 8, the plate-like member 54 has a square outer shape, and through holes 54c are formed at the four corners. The through hole 54c is formed at a position corresponding to the through hole 52k of the connecting member 52 when the plate-like member 54 is overlapped on the rising plate portion 52h of the connecting member 52 from the lower side. The diameter dimension is smaller than that.

  As shown in FIG. 7, the plate-like member 54 has a support rod member 56 inserted through a through-hole 54 d formed in the center thereof, and the upper surface 54 a and the outer peripheral surface in the vicinity of the insertion portion of the support rod member 56 are welded. By doing so, it is provided integrally with the support bar member 56.

  The support rod member 56 has a male screw portion 56 a formed on the outer periphery of a portion protruding upward from the upper surface 54 a of the plate-like member 54. Further, the support bar member 56 has a convex spherical surface portion 56 c formed at the tip end portion of a columnar protruding portion 56 b that protrudes downward from the lower surface 54 b of the plate-like member 54.

  In FIG. 6, the convex spherical surface portion 56 c at the tip of the protruding portion 56 b of the support bar member 56 is in contact with the upper surface 74 a of the ball guide 74 of the ball bearing 60.

  Then, the male screw portion 58a of the bolt 58 is inserted into the through hole 54c from the upper surface 54a side of the plate-like member 54, and the tip portion protruding downward is the upper surface 74a of the ball guide 74 of the ball bearing 60, as shown in FIG. As described above, screws are fastened to the female screw portions 74 c formed at four locations and are fixed to the ball bearing 60.

  The upper surface 74 a of the ball guide 74 is engaged with or detached from the convex spherical surface portion 56 c of the support bar member 56 fixed to the plate-like member 54 according to a change in the distance between the base floor surface 41 and the plate-like member 54. Therefore, the plate-like member 54 is loosely connected to the ball bearing 60 with play.

  That is, as shown in FIG. 6, when the distance between the foundation floor 41 and the lower surface 54b of the plate-like member 54 is short and the head lower surface of the bolt 58 and the upper surface 54a of the plate-like member 54 are separated, the bolt 58 is The ball bearing 60 is not engaged with (disengaged from) the plate-like member 54, but the distance between the base floor surface 41 and the lower surface 54 b of the plate-like member 54 is widened so that the upper surface of the ball bearing 60 is When the distance between 74a and the lower surface 54b of the plate-like member 54 increases and the lower surface of the head of the bolt 58 contacts the upper surface 54a of the plate-like member 54, the ball bearing 60 is engaged with the plate-like member 54.

  Therefore, the bolt 58 is normally spaced from the upper surface 54 a of the plate-like member 54 when the tip of the male screw portion 58 a is screwed to the female screw portion 74 c of the ball guide 74. When the ball guide 74 of the ball bearing 60 is greatly lowered by the non-land surface (inclined surface or uneven surface) of the foundation floor 41, the bottom surface of the head of the bolt 58 is While contacting the upper surface 54a of the plate-like member 54, the ball guide 74 and the convex spherical surface portion 56c of the support bar member 56 are in the most separated state.

  Incidentally, as shown in FIG. 1, the head portion of the bolt 58 is assembled by being inserted from below into a through hole 52 k of a rising plate portion 52 h (see FIG. 4) of the connecting member 52. The through hole 52k of the rising plate portion 52h is arranged so that the head of the bolt 58 does not contact the inner peripheral surface of the through hole 52k when the support bar member 56 is rotated by a predetermined angle with respect to the ball bearing 60. The diameter dimension is considerably larger than the diameter dimension of the head of the bolt 58.

  Similarly to the through hole 52k of the raised plate portion 52h, the through hole 54c of the plate-like member 54 also has the male screw portion 58a of the bolt 58 when the support bar member 56 is rotated by a predetermined angle with respect to the ball bearing 60. The diameter dimension of the through hole 54c is formed to be considerably larger than the diameter dimension of the male screw portion 58a of the bolt 58 so as not to contact the inner peripheral surface of the through hole 54c.

  The plate-like member 54 fixed to the support bar member 56 and the ball bearing 60 are adapted to engage or disengage with each other via the bolt 58 as described above. Since the member 54 is loosely connected to the ball bearing 60 with play, the ball bearing 60 is allowed to rotate up to a predetermined angle with respect to the support bar member 56.

  Further, the plate-like member 54 and the ball bearing 60 fixed to the support rod member 56 are configured such that the heads of the bolts 58 are engaged with or detached from the upper surface 54 a of the plate-like member 54. And the ball bearing 60 can be changed or regulated.

  For this reason, a non-land surface is formed on the foundation floor surface 41 on which one seismic isolation support portion 44 is placed among a plurality of seismic isolation support portions 44 that support the seismic isolation frame 42, and other seismic isolation support portions 44 are provided. When the height position is lower than the foundation floor surface 41 on which the seismic support portion 44 is placed, the height is lowered so that the ball bearing 60 widens the distance from the lower surface 54b of the plate-like member 54. The ball body 70 is brought into contact with the foundation floor surface 41 uniformly.

  As shown in FIG. 9, the ball bearing 60 includes a large number of ball bodies 70, a ball seat 72, and a ball guide 74. The ball bearing 60 can guide the ball body 70 to circulate and roll through the gap S formed between the ball seat 72 and the ball guide 74.

  The ball seat 72 is formed in a disc shape having a convex spherical surface portion 72b on its outer peripheral portion, and a cylindrical portion 72a protruding upward in the figure is integrally formed at the upper center portion thereof. The cylindrical portion 72a has a smaller outer diameter than the convex spherical portion 72b, and four female screw portions 72e are formed on the upper surface 72c.

  The ball guide 74 is formed in a substantially cylindrical shape, and a concave spherical surface portion 74e corresponding to the convex spherical surface portion 72b of the ball sheet 72 is formed inside thereof. An opening of a concave spherical surface portion 74e is formed on the bottom surface 74b of the ball guide 74, and a step recess 74g that is recessed upward in FIG. 9 is formed above the opening.

  Then, four counterbore holes 74d penetrating from the upper surface 74a to the ceiling surface of the stepped recess 74g are formed at the center of the upper surface 74a of the ball guide 74.

  The cylindrical portion 72 a of the ball sheet 72 is fitted into the stepped concave portion 74 g of the ball guide 74, the male screw portion 76 a of the countersunk screw 76 is inserted into the center portion of the counterbore hole 74 d of the ball guide 74, and the tip end portion is inserted into the ball sheet 72. The ball guide 74 is fixed to the ball seat 72 by screwing the female screw portion 72e.

  At this time, between the concave spherical surface portion 74e of the ball guide 74 and the convex spherical surface portion 72b of the ball seat 72, a curved gap S as shown in FIG. Is formed. The central portion of the gap S in the ball guide 74 is formed in an annular shape in the horizontal cross section.

  Further, there is a step shorter than the outer diameter of the ball body 70 between the height of the bottom surface 74 b of the ball guide 74 from the foundation floor surface 41 and the height of the bottom surface 72 d of the ball seat 72 from the foundation floor surface 41. Is provided.

  For this reason, when the ball body 70 is spread on the base floor surface 41 below the bottom surface 72 d of the ball sheet 72, a part of the ball body 70 sandwiched between the bottom surface 72 d of the ball sheet 72 and the base floor surface 41. Is arranged to be exposed below the bottom surface 74 b of the ball guide 74.

  The ball body 70 is not only below the bottom surface 72d of the ball sheet 72 but also in a gap S formed between the concave spherical surface portion 74e of the ball guide 74 and the convex spherical surface portion 72b of the ball sheet 72, and is substantially adjacent to each other. Filled.

  Then, when the ball bearing 60 shown in FIG. 9 moves horizontally with respect to the base floor surface 41, the ball body 70 located on the opposite side to the side where the horizontal movement proceeds is below the bottom surface 72d of the ball seat 72. The ball body 70 that has entered the gap S and circulated and rolled and located on the traveling side of the horizontal movement moves toward the side opposite to the traveling side.

  For this reason, when the ball bearings 60 are moved horizontally by bringing the ball bearings 60 into contact with the foundation floor 41, the ball bearings 60 are circulated and rolled following the horizontal movements. By operating the body 70 in this way, the seismic isolation frame 42 can freely move in any horizontal direction on the foundation floor surface 41.

  In addition, as shown in FIG. 11, when the foundation floor 41 is inclined with respect to the horizontal plane, the ball guide 74 of the ball bearing 60 disposed thereon rotates a predetermined angle with respect to the support bar member 56. Thus, a large number of ball bodies 70 can be brought into uniform contact with the foundation floor surface 41 in the same manner as when the foundation floor surface 41 is not inclined.

  In such a base-isolated floor structure 40 according to the present embodiment, the relative angle between the support bar member 56 and the ball guide 74 of the ball bearing 60 can be changed according to the uneven surface of the foundation floor surface 41. Therefore, even if there is a portion where the non-land surface is formed on the foundation floor surface 41, the ball bodies 70 of all the ball bearings 60 can be brought into uniform contact with the foundation floor surface 41.

  Moreover, in the seismic isolation floor structure 40 according to the present embodiment, the vertical distance between the plate-like member 54 and the ball bearing 60 can be changed in accordance with the change in the height of the foundation floor 41. Even if the foundation floor surface 41 has a portion whose height is different from most other portions, the ball bodies 70 of all the ball bearings 60 can be brought into uniform contact with the foundation floor surface 41.

  As described above, the base-isolated floor structure 40 according to the present embodiment has the ball bodies 70 of all the ball bearings 60 even if the base floor surface 41 has a portion with a non-land surface or a portion with a different height. Since it can be made to contact with the foundation floor surface 41 uniformly, a seismic isolation operation | movement can be effectively performed with respect to the vibration and displacement of the horizontal direction of a building which arose by the earthquake etc.

  Moreover, in the seismic isolation floor structure 40 which concerns on this Embodiment, it is provided with the connection member 52 which connects a pair of flame | frame 46 arrange | positioned facing each other, and this connection member 52 of A plate-like member 54 (see FIG. 1) is arranged below the raised plate portion 52h (see FIGS. 4 and 5) where the end portions of the pair of frames 46 are raised upward, so that the seismic isolation floor structure is provided. An increase in the height dimension of 40 can be prevented.

  Further, in the base isolation floor structure 40 according to the present embodiment, the frame 46, the cover 48, and the connection frame 50 that constitute the base isolation frame 42 are fixed to the connection member 52, and the base isolation is performed. Since the support portion 44 is mainly constituted by the connecting member 52, the plate-like member 54, the support bar member 56, and the ball bearing 60, the seismic isolation floor structure 40 is simple in structure and easy to assemble. Therefore, the material cost and manufacturing cost can be reduced.

  Therefore, as described above, according to the seismic isolation floor structure 40 according to the present embodiment, the structure is simple, the material cost and the manufacturing cost can be reduced, and the basic floor surface 41 can be reduced. Even if there is a portion where a non-land surface is formed, it is possible to effectively perform a seismic isolation operation against horizontal vibration and displacement of a building caused by an earthquake or the like.

  In addition, instead of the convex spherical surface portion 56c, a chamfered portion in which a corner portion of the distal end portion is cut off at approximately 45 degrees may be formed at the distal end portion of the protruding portion 56b of the support bar member 56.

  Further, the support bar member 56 is inserted through the plate-like member 54, but the portion protruding from the upper surface 54a and the portion protruding from the lower surface 54b of the plate-like member 54 are configured by separate members. It does not matter if

2 Base-isolated floor structure 3 Base floor surface 4 Ball bearing 6 Floor plate 6a Upper surface 6b Lower surface 8 Ball body 10 Ball seat 10a Convex spherical surface portion 10b Bottom surface 12 Ball guide 12a Concave spherical surface portion 12b Upper surface 12c Female thread portion 14 Bolt 40 Base-isolated floor structure 41 Base floor surface 42 Seismic isolation frame 44 Seismic isolation support portion 46 Frame 46a Hollow portion 46b Through hole 47 Bolt 48 Cover 48a Through hole 50 Connecting frame 50a Hollow portion 52 Connecting member 52a Flat plate portion 52b Upper surface 52c Screw hole 52d Notch portion 52e Bending Plate portion 52f Long hole 52g Inclined portion 52h Swelling plate portion 52i Upper surface 52j, 52k Through hole 52m Lower surface 54 Plate member 54a Upper surface 54b Lower surface 54c, 54d Through hole 56 Support rod member 56a Male thread portion 56b Protruding portion 56c Convex spherical surface portion 58 Bolt 58a Screw part 60 Ball bearing 62 Nut 70 Ball body 72 Ball seat 72a Column part 72b Convex spherical surface part 72c Upper surface 72d Bottom surface 72e Female thread part 74 Ball guide 74a Upper surface 74b Bottom surface 74c Female thread part 74d Counterbore hole 74e Concave spherical part 74g Stepped concave part 76 Disc screw 76a Male thread S Clearance W Welding

Claims (4)

In the seismic isolation floor structure having a base isolation frame having a plurality of frames and a plurality of base isolation support parts for supporting the base isolation frame,
The seismic isolation support portion includes a ball bearing placed on a foundation floor, a plate-like member disposed above the ball bearing, and one end of the plate-like member fixed to the plate-like member. A support bar member projecting further downward,
The ball bearing is in contact with the one end portion of the support bar member so as to be tiltable.   The base-isolated floor structure according to claim 1, wherein a convex spherical surface portion or a chamfered portion is formed at a tip of the one end portion of the support bar member. The seismic isolation support part is inserted into a through hole formed in the plate-like member connected to the seismic isolation frame with one end fixed to the ball bearing and the other end extending upward. An engagement bar member,
The other end of the engaging Gobo member, wherein the said base floor and in response to changes in the spacing of the plate-like member, characterized in that it disengaged from or the upper surface on the upper surface of the plate-like member Item 3. The base-isolated floor structure according to item 1 or 2. The seismic isolation support part includes a connecting member that connects the frames arranged so that their ends face each other, and a base isolation leg part placed on the foundation floor surface,
The connecting member has a rising plate portion formed so as to rise upward between the frames in which the respective end portions are opposed to each other,
The seismic isolation floor structure according to any one of claims 1 to 3, wherein the seismic isolation leg portion is disposed below the raised plate portion.

Images