JPH0587624B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a seismic isolation floor against external vibrations such as earthquakes. [Conventional technology and its problems] In order to make the floor a seismic isolation structure, a movable part such as a floor panel is formed above the fixed part of the concrete floor, and a spring is inserted between the movable part and the fixed part. It is conceivable that a seismic isolation mechanism such as rubber, bearings, etc. will be provided to support the moving parts. For example, one method is to place coil springs on a concrete floor at appropriate intervals and then lay floor panels on top of them.This method is effective against vertical shaking, but in the event of an earthquake there is a large amount of horizontal vibration. Therefore, restoration against movement in the horizontal direction is important, and such a large restoring force in the horizontal direction cannot be obtained by providing coil springs scattered in the vertical direction. In addition, floor panels that support floor panels with bearings can follow relative horizontal displacements, but cannot provide restoring force, so it is necessary to use a separate horizontal tension spring in combination. It is designed to exert a restoring force, and if this tension spring is strong, problems such as obstructing the movement of the bearing will occur, making it extremely difficult to adjust the two. Furthermore, such bearing bearings provide only horizontal two-dimensional seismic isolation, and do not take vertical seismic isolation into consideration. On the other hand, even if the floor panel as a movable part is directly supported by a seismic isolation mechanism, there is a problem with how to connect it, and even if it is bolted, if the floor panel is not thick enough, there will be metal fittings on the top surface. It comes out, making it difficult to use, and when repairs are needed, it is necessary to disconnect from the seismic isolation mechanism, which is very troublesome. The purpose of the present invention is to eliminate the disadvantages of the conventional example,
When relative displacement occurs due to external vibrations such as earthquakes, it is possible to effectively deal with displacement not only in the horizontal direction but also in the vertical direction, and because the floor panels are supported by their joists rather than directly, the displacement is reduced. The seismic isolation mechanism can effectively provide seismic isolation to the entire floor panel, and even if the partial load on the floor panel varies, it can be adjusted accordingly to prevent the entire floor panel from becoming uneven. Another object of the present invention is to provide a seismic isolation floor that allows easy installation and repair of the floor panel itself. [Means for Solving the Problems] In order to achieve the above object, the present invention forms a conical recess in which an elastic member is raised around the fixed part of the floor, and a large diameter steel ball is placed in the upper part of the conical recess. is stored in the central body serving as a storage holder via a spherical receiver, and the upper end surface of the large diameter steel ball is brought into contact with a large number of small diameter steel balls stored in the central body, and the central body A cylindrical body is slidably fitted into the upper part of the central body part, a stopper is provided at the bottom of the lower plate body provided so as to protrude from below to the outer periphery of the central main body part, and a stopper is provided at the bottom of the lower plate body, and further, a stopper is provided at the bottom of the lower plate body, and further, a stopper is provided at the bottom of the lower plate body, and the end of the upper plate of the cylindrical body is provided with a stopper. A vertical coil spring is disposed between the lower plate and this end, and a rod is vertically movably protruded from the end of the upper plate as a mechanism for adjusting the elastic force of the coil spring. The lower end of the rod receives the upper end of the coil spring, and a damper is protruded downward from the upper plate of the cylindrical body, its tip engages with the central body, and the flanges are extended from the upper plate to both the left and right sides. The gist is that the flange end is connected to the joist end, and a floor panel is laid on the joist via support legs. [Operation] According to the present invention, a large-diameter steel ball is placed in a conical recess, and since this conical recess has a linear upward slope toward the outside, the connection between the floor and the lower plate is The restoring force (the force that causes the steel ball to return to the center position of the conical recess) when a relative change occurs in the horizontal direction is regardless of the relative displacement between the two, that is, the amplitude, and regardless of the position. also always maintains a constant value uniquely determined by the inclination angle θ of the conical recess. Therefore, in the vibration system on the movable side, unlike the spring-mass system, the restoring force always maintains a constant value, so the natural frequency fn of the lower plate is as follows, where the amplitude is a.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a longitudinal sectional front view showing one embodiment of the seismic isolation floor of the present invention, and FIG. 2 is a longitudinal sectional front view showing details of the seismic isolation mechanism. To explain the seismic isolation mechanism A first, a protrusion 2 is provided protruding from the lower surface of the bottom of a seat 1 formed in a substantially flat shape, and a protrusion 2 is provided on the upper surface of the seat 1, with the center of the seat 1 being the deepest part, and the projection 2 extending from the outside. A conical recess 3 having a bottom surface having a linear upward slope toward the bottom was formed, and a barrier 9 made of an elastic member was erected around the conical recess 3. A large-diameter steel ball 4 having the same curvature as a whole, that is, a pure sphere, is placed on the conical recess 3 as a horizontal seismic isolation member.
The upper part of the steel ball 4 is stored in the central body part 5 as a storage holder via spherical receivers 6a and 6b, and the upper end surface of the steel ball 4 is connected to a large number of small diameter steel balls 7 stored in the central body part 5. bring it into contact. 8 in the figure indicates spherical receivers 6a, 6 inside the central body portion 5.
This is a snap spring for fitting and fixing b. By slidably fitting the lower plate 10 having a cylinder on the upper surface to the lower end of the central body 5, the lower plate 10 is provided so as to protrude from below to the outer periphery of the central body 5. A stopper 11 is provided protrudingly at the lower center of the lower plate body 10. A cylindrical body 13 as an upper member is slidably fitted to the upper part of the central body part 5 via a bearing member 12, and the end part 14a of the upper plate 14 is made to protrude to the outer periphery, and the lower plate body 10 and A coil spring 15 is disposed between the ends 14a as a vertical seismic isolation member. When arranging this coil spring 15, the end portion 14a
As a mechanism for adjusting the elastic force of the spring 15, a rod 16 is protruded downward from the spring 15 so as to be movable up and down, and the upper end of the coil spring 15 is brought into contact with the lower end of the rod 16. As a mechanism for adjusting the length of the rod 16, the rod 16 is a screw and is screwed into a nut. Further, an oil damper 17 is provided to protrude downward from the center of the top plate 14, and the tip of the rod 17a is locked to the central body portion 5, and further, a flange 18 made of a vertical plate is installed from the upper surface of the top plate 14 on both the left and right sides. to protrude to. In the figure, 19 is a lock nut for positioning the oil damper 17. In order to install such a seismic isolation mechanism A, as shown in FIG. Joist 2 made of steel frame with stops etc.
Join at 3 ends. Therefore, the joists 23 are connected to each other via the flanges 18, and a floor panel 24 is laid on the joists 23 via support legs 25. In addition, as another example, the concrete floor 22
It is also conceivable to omit this and to provide the seat part 1 on a beam as a fixed part of the floor. Next, the usage and operation will be explained. Normally, the large diameter steel ball 4 is located at the deepest center of the conical recess 3, and the load applied to the floor panel 24 is transferred to the concrete through the coil spring 15 and the steel ball 4. This is transmitted to the floor 22 side, but since there is an oil damper 17, the coil spring 1 is
The elastic force 5 does not act, and the floor panel 24 does not move up and down. In addition, there are cases where equipment such as computers is placed on the floor panel 24 and a large load is applied to a portion of the floor panel 24. In that case, the rod 16
If the spring 15 is adjusted so that the elastic force of the spring 15 can be strongly exerted, there is no possibility that the floor panel 24 will partially sink or otherwise become uneven. Due to external vibrations such as earthquakes, the concrete floor 22
When a relative horizontal displacement occurs between the joists 23 and 23, the large diameter steel ball 4
By rolling in a so-called running up state on the upper surface, it is possible to cope with the relative displacement in the horizontal direction regardless of the magnitude, and when the displacement is released, the large diameter steel ball 4 rolls so as to slide down toward the center. do. When the rolling motion of the steel ball 4 becomes large, the stopper 11 becomes a barrier 9 made of an elastic member.
The so-called shock is absorbed. Furthermore, regarding the rolling of the steel ball 4, if the shape of the recess that receives the steel ball 4 is circular, the period will be constant depending on the circular shape (radius of curvature); In the case of the recess 3, the period is determined by the amplitude of movement of the steel ball 4 due to vibration, so even if it becomes resonant, the increase in amplitude due to resonance enters a new natural periodic band, so there will be no resonance. . In this way, as the swing width increases, the period tends to become longer, so the vibration is converted to a longer period and is transmitted to the joist 23 with less shaking, and the vibration is transmitted to the joist 23, Seismic isolation is provided to the installed floor panel 24 via the supporting legs 25. And, the steel ball 4 is always in the conical recess 3
Since it returns to the center, when the horizontal relative displacement is released, it automatically returns to its original position, resulting in what is called a repositioning. On the other hand, regarding vertical displacement, the damper 17 exerts the desired buffering function for initial slight displacements, and for larger displacements, the coil spring 15 provides a buffering function. In this way, horizontal and vertical three-dimensional seismic isolation can be obtained.Furthermore, the seismic isolation mechanism A is interposed as a connecting member at the connecting portion of the mutual ends of the joists 23, and By seismically isolating the entire structure, this effect is directly transmitted to the floor panel 24 above it. [Effects of the Invention] As described above, the seismic isolation floor of the present invention can withstand small displacements even if displacement occurs in the horizontal and vertical directions due to an earthquake or the like between the fixed part of the floor and the floor panel as the movable part. Of course, it can effectively cope with large displacements with the necessary damping action, and is also excellent in returning to its original position after the displacement is completed. In addition, the floor panel as a movable part is supported by the seismic isolation mechanism through the joists, so it can be easily constructed without complicated installation, and repairs can be easily performed. Furthermore, since the elastic force of the coil spring can be adjusted as appropriate, there is no risk of unevenness even if a heavy load is applied to a portion of the floor panel.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing one embodiment of the seismic isolation floor of the present invention, and FIG. 2 is a longitudinal sectional front view showing an example of the seismic isolation mechanism used in the invention. 1... Seat, 2... Protrusion, 3... Conical recess,
4...Large diameter steel ball, 5...Central main body, 6a, 6b...Spherical receiver, 7...Small diameter steel ball, 8...Snat spring, 9...Barrier, 10...Lower plate, 11...stopper, 1
2...Bearing member, 13...Cylinder body, 14...Top plate, 14a...End portion, 15...Coil spring, 16
... Rod, 17... Oil damper, 17a...
... Rod, 18 ... Flange, 19 ... Lock nut, 22 ... Concrete floor, 23 ... Joist,
24...floor panel, 25...support leg.

Claims (1)

[Claims] 1. A conical recess with an elastic member raised around the periphery is formed in the fixed part of the floor, and the upper part of a large diameter steel ball placed here is stored in the central main body part serving as a storage holder via a spherical receiver, Further, the upper end surface of the large diameter steel ball is brought into contact with a large number of small diameter steel balls housed in the central body, and a cylindrical body is slidably fitted into the upper part of the central body. A stopper is provided protruding from the lower part of the lower plate provided to extend from below to the outer periphery, and further, an end of the upper plate of the cylindrical body is extended to the outer periphery, and a stopper is provided vertically between the lower plate and this end. A rod is provided at the end of the top plate so as to be movable up and down as a mechanism for adjusting the elastic force of the coil spring, and the lower end of the rod receives the upper end of the coil spring. A damper is provided to protrude downward from the top plate, and its tip engages with the central body part, and flanges are provided to protrude from the top plate to both left and right sides, the flange ends are joined to the joist ends, and the dampers are supported on the joists. A seismic isolation floor characterized by having floor panels installed through legs.