Patent Publication Number: US-2011047909-A1

Title: Free access floor and partitioning method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2009-198545, filed on Aug. 28, 2009, the entire contents of which are incorporated herein by reference. 
     FIELD 
     The embodiment discussed herein is related to a method of forming a floor structure and an underfloor space and, more particularly, to a technique of partitioning the underfloor space. 
     BACKGROUND 
     There is known a free access floor (also referred to as “raised floor” or “free access”) formed by laying floor panels (free access panels) in a bridged manner over supporting legs regularly arranged in a raised manner on a base floor face. Further, there is known a floor structure in which the underfloor space of the free access floor is partitioned by arranging a partition plate between two supporting legs (refer to, e.g., the following Patent Document 1). In the floor structure of Patent Document 1, the upper section of the partition plate is fixed onto a pedestal for placing a panel in a support leg, and the lower section of the partition plate is fastened onto an L-shaped angle material fixed and mounted onto a base floor face or the base plate of the support leg. Then, a plate supporter is set up to the L-shaped angle material in a height adjustable manner and the lower section of the partition plate is fixed onto the plate supporter. 
     [Patent Document 1] Japanese Patent No. 3914315 
     Although the above mentioned prior art allows the underfloor space of the free access floor to be partitioned by the partitioning plate, the structure for fixing the partitioning plate is complicated. For example, in a data center, there may be a case where the number of racks accommodating IT devices is frequently increased/decreased or the layout of the racks is frequently changed. In such a case, the complicated structure in the above mentioned prior art makes it difficult to change the direction of the flow of air such as cooling air flowing in the underfloor space. Therefore, a heat problem casing a system to be unstable, such as heat accumulation (hot spot generated in an area, such as air intake faces of the IT devices, where the temperature should be kept low), easily occurs. Further, there may be a case where cold air is diffused in the underfloor area at which no rack is installed (cooling is unnecessary) in the initial phase of the system operation in the data center, resulting in the use of extra air-conditioning power. Such power consumption is considered to be a serious problem at the present circumstances where the scale of the data center is increased with progress of IT and it is necessary to reduce a power consumption so as to reduce carbon dioxide emissions in the large-scale data center. 
     SUMMARY 
     According to an aspect of the invention, a free access floor formed by free access panels arranged above a base floor is provided. The free access floor includes a specific panel that is one of the free access panels and has a slit, and a partitioning plate inserted into the slit, so as to hang down from a surface of the specific panel and orient airflow in a space between the base floor and the free access panels. 
     The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a plan view illustrating a part of a free access floor; 
         FIG. 2  is a side view illustrating the part of the free access floor of  FIG. 1 ; 
         FIG. 3  is a cross-sectional side view illustrating a state where a partitioning plate is set in a free access panel; 
         FIG. 4  is a cross-sectional side view illustrating a state where the partitioning plate is not set in the free access panel; 
         FIG. 5  is a plan view illustrating examples of a case where a plurality of partitioning plates are set in one free access panel; 
         FIG. 6  is a cross-sectional view illustrating a flexible partitioning plate; 
         FIG. 7  is a cross-sectional view illustrating a state where the flexible partitioning plate is used; 
         FIG. 8  is a view illustrating a method of fixing the flexible partitioning plate to a supporting portion; 
         FIG. 9  is a view illustrating another example of the fixing method of the flexible partitioning plate; and 
         FIG. 10  is a view illustrating an example of a free access floor in which a flow path of cooling air is formed. 
     
    
    
     DESCRIPTION OF EMBODIMENT 
     An embodiment of the present invention will be described below with reference to the accompanying drawings. A free access floor according to the embodiment can be applied to a floor of a data center where the number or layout of racks accommodating servers and the like is frequently changed. 
       FIG. 1  is a plan view illustrating a part of the free access floor, and  FIG. 2  is a side view illustrating the part of the free access floor of  FIG. 1 . In  FIGS. 1 and 2 , a plurality of free access panels  1   a  are arranged in a plane to form a free access floor  1 . The free access floor  1  is supported by a plurality of pillars  3  raised on a base floor  2 . A space is formed between the free access floor  1  and the base floor  2 . 
     In the present example, the free access panels  1   a  each have a rectangular shape, and the pillars  3  each support the area where the vertexes of the four free access panels  1   a  contact each other. Thus, the pillars  3  each support the vertexes of the free access panels  1   a  at substantially the center of its support surface. 
     Some free access panels (specific panels) among the plurality of free access panels  1   a  have a slit  5 . The slit  5  is formed in any one or plurality of free access panels (specific panels)  1   a  among the plurality of free access panels  1   a.    
       FIG. 3  is a cross-sectional side view taken along the II-II line of  FIG. 1  in a state where a partitioning plate is set in a free access panel. A partitioning plate  6  that orients airflow in the space between the base floor  2  and free access floor  1  is inserted into a given slit  5  among the plurality of slits  5 , as illustrated in  FIG. 3 . In other words, the partitioning plate  6  determines the direction of the flow of air flowing in the space. The partitioning plate  6  is detachably provided so as to hang down from the surface of the free access panel  1   a.    
     In the configuration described above, the slit  5  is, in the free access panel  1   a  in which the slit  5  is formed, formed to extend between the pillars  3  that support the free access panels  1   a  on the base floor  2 . Insertion of the partitioning plate  6  into the slit  5  allows the space in one direction of the free access panel  1   a  to be partitioned by the pillars  3  and the partitioning plate  6 . 
       FIG. 4  is a cross-sectional side view taken along the II-II line of  FIG. 1  in a state where the partitioning plate is not set in the free access panel. As illustrated in  FIG. 4 , to the slit  5  into which the partitioning plate  6  is not inserted, a closing plate  7  is fitted so as to close the slit  5 . More specifically, a step  5   a  is formed on the upper surface side of the free access panel  1   a , and the closing plate  7  is fitted to the step  5   a  to thereby close the slit  5  while making the surfaces of the free access panel  1   a  constituting the free access floor  1  flush with each other. When the partitioning plate  6  is used, a support portion  6   a  formed at the upper edge of the partitioning plate  6  is stopped by the step portion  5   a , whereby the partitioning plate  6  is supported by the free access panel  1   a.    
     The partitioning plate  6  illustrated in  FIG. 3  is a plate member made of e.g., wood or plastic and is formed integrally with the supporting portion  6   a.    
     In the example of  FIG. 1 , one slit  5  is formed in one free access panel  1   a . However, as illustrated in  FIGS. 5A ,  5 B, and  5 C, a plurality of slits  5  may be formed in one free access panel  1   a  for receiving the insertion of the partitioning plate  6 . In the case of  FIGS. 5A ,  5 B, and  5 C, the plurality of slits  5  are formed so as to extend along the respective sides of the rectangular free access panel  1   a  perpendicularly or in parallel to each other. 
     Another configuration of the partitioning plate will be described. Although the partitioning plate  6  is formed of a plate member in the example of  FIG. 3 , a partitioning plate  16  illustrated in  FIG. 6  is formed of a flexible member. The partitioning plate  16  of  FIG. 6  has a configuration in which a partitioning portion  16   b  formed of a flexible member such as a flexible fabric having a sufficient size and shape to partition the space under the panel is fixed to a support portion  16   a , and a plurality of weights  16   c  are fitted to the lower edge of the partitioning portion  16   b . In other words, the plurality of weights  16   c  are attached to a lower edge of the partitioning portion  16   b . The fabric may be a chemical fiber (nylon, polyester, etc.) or vinyl chloride sheet. The weight  16   c  may be a metal material (iron, etc.) or a plastic resin material. 
     The use of such a flexible partitioning plate  16  allows the hanging amount (length of the partitioning portion  16  in the height direction) of the partitioning plate  16  to be adjusted so as to, e.g., prevent the upper end portion (support portion  16   a ) of the partitioning plate  16  from protruding from the free access floor  1  even when an obstacle  9  exists on the base floor  2 , thereby easily partitioning the underfloor space. Further, even when the level of the base floor  2  is raised as illustrated in  FIG. 7B , the use of the flexible partitioning plate  16  allows easy partitioning of the underfloor space. 
     In the case where the flexible partitioning plate is used, the partitioning plate may be fixed to the support portion as follows. That is, the upper edge  16   d  of the flexible member  16   b  constituting the partitioning portion  16   b  is adhered to the support portion by adhesives as illustrated in  FIG. 8  or the upper edge  16   d  of the flexible member  16   b  is mechanically fixed to the support portion by tacks, pins, or screws  11  as illustrated in  FIG. 9 . 
       FIG. 10  illustrates an example of the free access floor  1  according to the present embodiment. The plurality of free access panels  1   a  each in which the partitioning plate  6  (or partitioning plate  16 ) is provided are combined to form a flow path R of cooling air in the underfloor space. Accordingly, the cooling air emitted from an air conditioner  20  is not made to flow in a location where cooling is unnecessary but is made to effectively flow only in the flow path R formed by the partitioning plates  6 , thereby reducing power consumption required for air conditioning. Further, the configuration of the flow path R can easily be changed by selecting whether to set or not the partitioning plate  6  to the slit of the free access panel  1   a  or selecting an appropriate slit to which the partitioning plate  6  is set in terms of its extending direction. In other words, the partitioning plate  6  orients airflow in the space between the base floor  2  and the free access panels  1   a . Accordingly, a partitioning method is provided. The partitioning method includes inserting the partitioning plate  6  into the slit  5 , so that the partitioning plate  6  hangs down from a surface of the free access panel  1   a , and orienting airflow in the space by the partitioning plate  6 . 
     Thus, according to the embodiment, the cooling air toward an area where cooling is unnecessary can easily be blocked during, e.g., the initial phase of the system operation in a data center, enabling a reduction of power cost of an air conditioner. Further, the free access floor  1  can easily be partitioned in accordance with an analysis area that is cut out from the free access floor  1  for modeling of air-condition simulation, increasing accuracy of analysis made by the air-condition simulation. Further, it is possible to easily partition the underfloor space from above the free access floor  1  in a state where racks or air conditioners are set in the free access floor  1  and to easily change the direction of the flow of wind in the underfloor space. 
     All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a depicting of the superiority and inferiority of the invention. Although the embodiment(s) of the present inventions have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.