Patent Publication Number: US-2010116448-A1

Title: Tensioning system for retractable screens and shades

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates generally to improved apparatus for keeping retractable able screens and shades in place, and, more particularly, to apparatus that involve tensioning the end of a screen or shade within a guide rail. 
     2. Description of the Related Art 
     Movable shades or screens have been provided for building window openings which, when in their extended position, provide security for the window opening, and when in their retracted position, provide passage of light, air, and the like, through the window opening. Additionally, movable security panels have been provided for door assemblies, show windows, and the like, in various retail merchandising stores where it is desirable to provide protection for the contents. 
     Typical retractable privacy shade assemblies of the prior art are shown in  FIGS. 1-3 .  FIG. 1  illustrates a retractable shade  10  that includes a horizontally disposed housing  12  which includes end walls  14  of conventional construction for receiving a conventional roller shade between a pair of guide rails  16  and an actuating mechanism in which the shade  18  is constructed of a plurality of slats hingedly interconnected in any suitable manner. The roller shade in and of itself including the guide rails  16  are conventional in construction as is the reel mechanism and actuating mechanism (in housing  12 ; not shown) for the shade so that when the shade  18  is retracted, it will be substantially completely received in the housing  12  and when it is completely extended (i.e., at the end of its downward movement), it will form a privacy barrier and/or security closure. 
     In  FIG. 2 , an exploded view of a retractable screen  20  (which may be, for example, a mesh material or flexible shade screen) is shown. Within housing  22  are axle  24  (upon which screen  26  rolls to wind and unwind), crown  28 , drive  30 , motor  32 , and axle bearing insert  34 . Brackets  36  act as end caps for the actuating motor/crown/drive/bearing insert assembly, and a pair of parallel guide rails provide a slot  39  within which bottom  40  of shade  26  is guided in upward and downward motion. Bottom  40  typically is a bar that contains end caps  42 . 
     For all of the comfort and convenience offered by retractable screens and shades, many have suffered from the drawback of rattling, “banging,” or other distracting movement and noise during periods of wind. 
     To address this issue, independent tensioning systems designed for use in retractable screens and shades (also known as rolling screens or shades) have been developed. All of the retractable screens or shades of which the inventors are aware contain tensioning components within the slot  39  of guide rail  38 . Thus, as shown in magnified view in  FIG. 3 , a locking clip  44  can lock or tension the screen  46  in a particular location. 
     By disposing a lock, clip or other structure on or in the guide rail, the positions at which the screen may be tensioned necessarily are limited to the location of the clip or other tensioning structure in the space provided by the slot of the guide rail. In other words, only select positions will have a clip at which the screen can interface and be tensioned in place. 
     Accordingly, it would be desirable to provide a method and an apparatus that tensions screens and shades in place at substantially any location along the guide rail to keep it from rattling in the guide rail at any height desired by a user. 
     SUMMARY OF THE INVENTION 
     The invention generally involves a tensioning method and apparatus for retractable shades or screens. More particularly, embodiments of the invention include a tensioning mechanism attached to the end of a shade or screen. The tensioning mechanism resides within a guide rail and frictionally engages the sidewall of the guide rail during any retraction movement other than that occurring upon reaching the bottom of the shade&#39;s or screen&#39;s downward movement. 
     In one embodiment, the tensioning mechanism or member comprises a pivot arm. The pivot arm frictionally engages the sidewall such that the screen or shade is tensioned in place only during a retracting motion occurring prior to reaching a bottom of its downward motion. 
     Thus, there is provided new and improved methods and apparatus for tensioning a retractable shade or screen. 
     Various other purposes and advantages of the invention will become clear from its description in the specification that follows. Therefore, to the accomplishment of the objectives described above, this invention includes the features hereinafter fully described in the detailed description of the preferred embodiments, and particularly pointed out in the claims. However, such description discloses only some of the various ways in which the invention may be practiced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a retractable shade of the prior art. 
         FIG. 2  is an exploded diagram of a retractable screen of the prior art. 
         FIG. 3  is an enlarged view as seen from the perspective of arrow  3  of a clip lock system found in a rail of the prior art retractable screen of  FIG. 2 . 
         FIG. 4  illustrates an embodiment of the invention featuring a pivot arm mechanism disposed on a retractable screen or shade end. 
         FIG. 5A  schematically illustrates how the embodiment of  FIG. 4  functions as the retractable screen or shade travels downwardly from its housing. 
         FIG. 5B  schematically illustrates how the embodiment of  FIG. 4  functions as the retractable screen or shade travels upwardly to its housing after being “reset” at the bottom of its path down. 
         FIG. 5C  schematically illustrates how the embodiment of  FIG. 4  functions as the retractable screen or shade is retracted upwardly with the arm is set in its “downward movement position” to tension the screen in place at a desired location. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of the invention involve a tensioning mechanism disposed upon the end of a screen or shade that travels within a pair of guide rails. When the screen or shade end (e.g., the bottom bar) is moving down, the tensioning member slides freely within the guide rail. Conversely, when the screen or shade is retracted or reversed (i.e., moving upwardly towards the housing of the rolling axle), the tensioning member mechanically applies force to the sidewalls of at least one rail to frictionally bind and stop the rolling shade or screen in place. This allows the screen or shade to be stopped at any point along the guide rail and thereby apply tension to minimize rattling by the shade or screen. 
     To retract completely, the screen or shade is lowered to the bottom, where the tensioning member is reset, allowing the screen or shade to retract freely to the top without binding. Once completely retracted to the top, the tensioning member again will reset and enable the product to travel in the downward direction. 
     Turning to a first embodiment of the invention that would be suitable for the rolling screen shown in  FIG. 2  (and referring by numeric reference to the elements depicted therein), a pivot arm mechanism disposed on a retractable screen or shade end is illustrated in  FIG. 4 . 
     A tensioning member  50  is attached via fasteners  51  to the end member, bar  40 , of the screen  26  where end caps  42  are located. Thus, tensioning member  50  would be positioned in a guide rail  38  (e.g., within slot  39 ) of an assembled rolling shade. The tensioning member  50  of this embodiment comprises a pivot arm  52  coupled to a spring  54  that is attached to the face of the tensioning member  50  with fasteners  56 . Serrations  58 , or other suitable gripping surfaces or materials (e.g., rubber), may be disposed upon opposing sides of the tensioning member as illustrated. 
     In a particularly preferred embodiment, each end of the bar  40  (i.e., where each end cap  42  is located) includes a tensioning member  50  such that each of the pair of guide rails  38  will be engaged as described in more below. 
       FIG. 5A  schematically illustrates how the embodiment of  FIG. 4  functions as the bar  40  of the retractable screen or shade  26  travels downwardly (M 1 ) from its housing  22  (see  FIG. 2 ). The pivot arm  52  of tensioning member  50  is in a first position (P 1 ) corresponding to movement Ml that slidably engages a first sidewall  60  of guide rail  38 . The second side wall  64  is not frictionally engaged. Thus, the screen  26  continues traveling downwardly until stopped at a desired location. 
     Conversely,  FIG. 5B  schematically illustrates how the embodiment of  FIG. 4  functions as the retractable screen or shade travels upwardly (M 2 ) to its housing  22  after being “reset” at the bottom of its path down. The pivot arm  52  of tensioning member  50  is in a second position (P 2 ) corresponding to movement M 2  that slidably engages a first sidewall  60  of guide rail  38 . Again, the second side wall  64  is not frictionally engaged. Thus, the bar  40  of screen  26  continues traveling upwardly until stopped at a desired location. 
       FIG. 5C  schematically illustrates how the embodiment of  FIG. 4  functions as the retractable screen or shade is reversed in direction. In this case, the bar  40  is traveling in the M 1  direction so that arm  52  is in the P 1  position. When the bar  40  is then retracted upwardly (R 1 ), arm  52  pivots and acts on spring  56  to urge the tensioning member  50  to engage second sidewall  64 . Thus, both sidewalls  60  and  64  are engaged, resulting in tension that keeps the screen in place at a desired location. Simply reversing the direction of the bar  40  (in this case, resuming movement in the M 1  direction) results in the arm returning to the P 1  position and disengages the tensioning member  50  from the sidewalls of guide rail  38 . 
     Thus, it will be appreciated that tensioning member  50  operates to frictionally engage at substantially any point a sidewall within said a guide rail. 
     As further illustrated in  FIG. 5C , guide rail  38  includes a reset notch  68  located proximal to a bottom  70  of the guide rail. If tensioning member  50  is installed on both ends of bar  40 , than both the guide rails  38  will have a reset notch. When the arm  52  in the P 1  position reaches the notch  68  after traveling in the MI direction, a third position (P 3 ) is attained (see  FIG. 4 ). Upon reversal of direction (e.g., traveling in the M 2  direction), the arm  52  is now in the P 2  position. It will be appreciated that a reset notch or similar means for allowing the arm  52  to “reset” will also be located at the top of guide rail  38 . 
     In view of the apparatus described above, a method of tensioning a retractable screen or shade is provided. In one embodiment, the method includes (1) providing a retractable screen or shade having an end member disposed within a pair of guide rails, wherein a tensioning member is attached to the end member (e.g., a bar) of the screen or shade such that the tensioning member is positioned within at least one of said guide rails, and wherein the tensioning member operates to frictionally engage at substantially any point a sidewall within the guide rail, (2) moving the screen or shade in a first direction; and; (3) reversing the direction of the screen or shade, thereby actuating frictional engagement of the sidewalls within the guide rail by the tensioning member. 
     The tensioning member is reset to travel freely in the opposite direction by first moving the screen or shade to a top or bottom end within the guide rail. 
     The tensioning apparatus and method can tension the material on a variety of shade or screen systems controlled manually or electrically. The system controls only need to stop under tension and be able to move downwardly to release the tension. This operation can be used with crank gears, motorized systems and hand pull systems. 
     Various changes in the details and components that have been described may be made by those skilled in the art within the principles and scope of the invention herein described in the specification and defined in the appended claims. Therefore, while the present invention has been shown and described herein in what is believed to be the most practical and preferred embodiments, it is recognized that departures can be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent processes and products. All references cited in this application are hereby incorporated by reference herein.