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CROSS-REFERENCE TO DISCLOSURE DOCUMENT  
       [0001]     A disclosure document entitled Building with Independently Rotatable Suspended Floor Structure (Turning Tower) filed Dec. 2, 2004 as Disclosure Document No. 565968 is referred to herein and incorporated by reference.  
       CONTEXT OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     This invention relates to static structures and especially to a structure mounted for in situ repositioning.  
         [0004]     In particular, the structure of this invention concerns a building having floor units that are rotatable about a vertical axis.  
         [0005]     2. Background Information  
         [0006]     The ability of an apartment to command a desirable view is a recognizable factor in determining the salability and economic value of the apartment. However, most buildings have only a limited number of apartments with highly desirable exposures. A solution to this problem is to provide a changeable environment by in situ repositioning of the building. Typically, repositionable building structures were designed with an outer casing rotatably mounted on a spindle; the structures were used principally for observation towers, amusement devices, and/or restaurants for providing patrons with changeable views and not for apartment, hotel and similar dwellings; examples of such structures are shown in U.S. Pat. Nos. 3,905,166, 6,742,308, and 841,468.  
         [0007]     A limitation of these structures is that they are not intended primarily for use as multi-story apartment buildings or hotels or for providing selective 360° viewing capability. Another shortcoming is that lack of floor independence decreases load stability.  
       BRIEF SUMMARY OF THE INVENTION  
       [0008]     Briefly, the nature of this invention involves a building structure having a vertically disposed central core with plural horizontal floor units suspended from and surrounding the core at incremental heights for transferring balanced vertical loading through the core. An annular platform extending horizontally from the core, in correspondence with the floor units, provides a corridor for accessing the central core. The floor units are independently displaceable about the core, for example, by motor-power actuation, wind-power, electro-magnetic energy, or other drive force.  
         [0009]     In view of the foregoing, it should be apparent that the present invention overcomes the limitations of the prior art and provides an improved rotatable building structure.  
         [0010]     Having thus summarized the invention, it will be seen that it is an object thereof to provide a rotatable building structure of the general character described herein which is not subject to any of the aforementioned limitations.  
         [0011]     Another object of this invention is to provide a rotatable building structure suitable for high-rise or low-rise buildings.  
         [0012]     A further object of this invention is to provide a rotatable building structure with independently rotatable suspended floor units that provide improved seismic stability.  
         [0013]     A still further object of this invention is to provide a rotatable building structure wherein the configuration of the floor units can optionally be varied in shape such that the profile of the building will continually change during rotation of the floor units.  
         [0014]     Still another object of this invention is to provide a rotatable building structure including a stationary platform providing an accessway from the floor unit to the central core.  
         [0015]     Yet another object of this invention is to provide a rotatable building structure having single or multiple vertical cores for supporting the floor units.  
         [0016]     Still yet another object of this invention is to provide a rotatable building structure wherein displacement of the floor units are computer-controlled and actuatable on command.  
         [0017]     Yet still a further object of this invention is to provide a rotatable building structure having prefabricated furnished floor units to facilitate erection and onsite installation.  
         [0018]     Yet still another object of this invention is to provide a rotatable building structure with aerodynamically designed floor units that can be repositioned to reduce wind load, as in a hurricane.  
         [0019]     Other objects of this invention will in part be apparent and in part will be pointed out hereinafter.  
         [0020]     With these ends in view, the invention finds embodiment in certain combinations of elements and arrangements of parts by which the aforementioned objects and certain other objects are hereinafter attained, as more fully described with reference to the accompanying drawings and the scope of which is more particularly pointed out and indicated in the appended claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]     In the accompanying drawings, in which are shown an exemplary embodiments of the invention:  
         [0022]      FIG. 1  is a perspective new illustrating a portion of a multi-story building in accordance with this invention having independently rotatable floor units surrounding a central core;  
         [0023]      FIG. 2  is a plan view of the rotatable building structure of this invention showing a central core, a platform projecting from the central core and the floor units;  
         [0024]      FIG. 3  is a perspective view of the rotatable building structure of this invention showing a floor unit suspended from the central core;  
         [0025]      FIG. 4  is a perspective view of the rotatable building structure of this invention detailing the attachment of the floor unit to a respective upper and a lower rail for supporting the floor unit;  
         [0026]      FIG. 5  is a sectional view of the rotatable building structure of this invention taken substantially along lines  5 — 5  of  FIG. 4  showing in detail the central core, the platform, the upper rail, the lower rail, and a motor drive for displacing the floor unit;  
         [0027]      FIG. 6  is an elevational view of an alternate embodiment of the rotatable building structure of this invention showing a floor unit with a wind tool in operational position for providing wind-power assist during rotational displacement of the floor unit around the central core;  
         [0028]      FIG. 7  is a schematic illustration of an alternate embodiment of the rotatable building structure of this invention showing a platform with a track for supporting a floor unit; and  
         [0029]      FIG. 8  is an elevational view of the rotatable building structure of this invention showing a variable building profile formed by a plurality of floor units mounted along a horizontal plane asymmetrically with respect to the central core. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0030]     With specific reference now to the figures in detail, it is stressed that the particulars shown are by way of example and for the purposes of illustrative discussion of the preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt has been made to show aspects of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken together with the drawings should make it apparent to those skilled in the art how the several forms of the invention may be embodied in practice.  
         [0031]     Referring now in detail to  FIG. 1  of the drawings, there is shown a portion of a multi-level rotatable building structure  10  having an independently rotatable suspended floor unit  12 . It should be understood that the structure of this invention encompasses application to high-rise and/or low-rise buildings. The arrows are intended to show that each of several floor units  12  can rotate in opposite circular directions or optionally can rotate in the same circular direction. The floor units can also operate at different speeds.  
         [0032]     Referring next to  FIG. 2 , there is shown in plan view of a central core  14 , preferably cylindrical in shape, and constructed of reinforced concrete, structural steel or equivalent materials. A platform  22  is attached to or formed integrally with the central core  14 . The core  14  is designed to support the total live and dead load of the floor units  12 . The floor units  12  surround the core  14  and provide for balanced load transfer to the core  14 . The floor units  12  can be nonuniform shapes and/or mounted asymmetrically with respect to the central core  14 , as for example, is shown in  FIG. 8 , with a counterweight applied to achieve balanced loading. It should be noted that this later arrangement of floor units  12  will provide a variable building profile during rotation. As will be further noted, the floor units  12  can be connected along a horizontal plane to form floor levels at incremental vertical heights along the central core  14  and are supported in cantilever fashion from the central core  14 . In the event of seismic loading, the free ends of the respective floor units  12  may be subjected to movement without resulting in stress fracture, as may be the case if the separate floor levels were interconnected.  
         [0033]     The mechanical/electrical components such as an elevator shaft  16 , an emergency stairway  18 ; HVAC, water supply systems, trash disposal, electrical power cables, and utilities, such as, telephone, computer, television, jointly designated  20 , are housed within the central core  14 . It should also be noted that the core  14  has an opening (not shown) to provide a passageway from the platform  22  to the interior of the core  14 , for example, for occupants to access the elevator shaft  16 .  
         [0034]     As further noted in  FIG. 3 , in this preferred embodiment, the floor unit  12  is substantially a wedge-shaped, open-frame segment that is preferably fabricated of structural steel, aluminum, a combination of the above, however, other materials may be suitably utilized. A plurality of connected floor units  12  are designed to encircle the core  14  to provide a circular periphery. A roof member  21  and a floor member  23  are secured to the frame segment to form an enclosure. Note that a portion of the floor member  23  as shown in  FIG. 3  has been displaced to better illustrate the connection to the core  14 . The floor unit  12  also has a peripheral exterior curved boundary wall  24 , preferably made of a transparent material, for providing maximum visibility from within the floor unit  12  and an interior boundary wall (not shown) adjacent the platform  22  with an occupant passageway through the interior boundary wall for accessing the platform  22 .  
         [0035]     Concerning next the securement of the floor units  20  to the central core  14 , there is provided an upper rail  26  and a lower rail  28 , as shown in  FIGS. 3, 4  and  5 , designed for supporting the floor unit  12 . With regard to rotational displacement of the floor unit  12 , a roller bearing  30  is mounted to a distal end of an arm  27  extending from the roof member  21 . The roller bearing  30  is adapted to ride within a raceway  32  defined by the upper rail  26 . A safety lock  34 , also extending from the arm  27 , is positionable below the raceway  32  for securing the roller bearing  30  in the raceway  32 . Another raceway  36  is defined in the lower rail  28  and is adapted to accommodating a drive wheel  38 . The drive wheel  38  is actuated by an electric motor  40  mechanically linked to the drive wheel  38  by a beveled gear arrangement  42  or by other drive force. The gear ratio can be designed to the operating specifications. The motor drive  40  can also be computer operated by command at selected speeds and directions for displacing the floor unit  12  in either a clockwise or counterclockwise direction.  
         [0036]     Although the floor unit  12  has been described as defining a circular periphery surrounding the core  14 , alternative floor unit configurations e.g. square, ellipsoid, or non-symmetric shapes are within the scope of this invention, and will provide a continually changeable building profile during displacement. It should also be noted that the radial dimension of the floor units  12  can be varied, for example, from floor level to floor level, so as to create a variable building profile. Additionally, the exterior boundary wall  24  can be aerodynamically designed and selectively positionable for reducing wind load, especially during hurricanes.  
         [0037]     It is also within the scope of this invention to employ prefabricated floor units  12 , with the respective unit containing factory-furnished interiors of an apartment, a hotel room, an office space, such as partition walls, floors, mechanical equipment, HVAC, plumbing connections, electrical connections, and the like.  
         [0038]     In an alternate embodiment, wherein the same reference numerals have been used for designating corresponding parts of the previously described embodiment with the suffix “a”, a floor unit  12   a  is connected to a central core  14   a  in a manner as described herein (see  FIG. 6 ). In this embodiment, a wind tool  46  is shown deployed for providing a wind-power assist to the previously discussed motor drive. The wind tool  46  is comprised of a planar vane  48  hingedly connected to a spindle  50  mounted to a peripheral wall  24   a  of the floor unit  12   a . The vane  48  can be remotely and/or directly actuated for deployment to an operational mode from a retracted mode housed within the floor unit  12   a . A bar  52  provides a rotational limit stop to prevent further rotation of the vane  48  when in the fully deployed position. The wind tool  46  can alternatively be used for electrical power generation, for example, for recharging a backup battery system.  
         [0039]     In a further alternate embodiment as shown in  FIG. 7  wherein the same reference numerals have been used for designating corresponding parts of the previously described embodiment with the suffix “b”, a floor unit  12   b  is connected to a central core  14   b  by a tension cable or steel strut  26   b . A slidable anchor bearing  30   b  is attached at a distal end of the strut  26   b . The anchor bearing  30   b  is contained within a slot  32   b . The slot  32   b  extends on a horizontal plane, around the circumference of the central core  14   b . The strut  26   b  is designed to support the floor unit  12   b . A modified platform  22   b  projects under a portion of the floor unit  26   b  to provide additional support thereto and further includes a roller bearing  38   b  mounted in a track (not shown) or equivalent slide means for permitting displacement of the floor unit  26   b  along the platform  22   b.    
         [0040]     It should further be apparent that since the independent floor units  12  at each floor level are each separated, for example, as noted in  FIG. 1 , any seismic force transmitted through the central core  14  would tend to be absorbed, in contrast to conventionally interconnected floors, and thus less likely to be subject the floor units  12  to stress failure. Also the aerodynamically designed and repositionable boundary wall  24  of the floor units  12  and the opening spacing between respective horizontal levels of floor units  12 , substantially reduce the wind load applied as compared to a conventional vertical wall structure.  
         [0041]     It should thus be seen that there is provided a rotatable building structure which achieves the various objects of this invention and which is well adapted to meet conditions of practical use.  
         [0042]     Since various possible embodiments might be made of the present invention or modifications might be made to the exemplary embodiments above set forth, it is to be understood that all materials shown and described in the accompanying drawings are to be interpreted as illustrative and not in a limiting sense.

Summary:
A rotatable building structure contains a vertical central core for supporting suspended floor units surrounding the core. An annular platform extends from the core at corresponding floor units for providing accessibility to and from the central core. The floor units contain a drive mechanism for rotational displacement. A wind tool deployable from the floor unit provides alternative wind power assist for rotating the floor units.