Abstract:
A device for lifting and lowering visual displays, such as television sets, video monitors, plasma displays, pieces of art, or the like. The elevating device includes an elevating mechanism that elevates a first sliding frame and a second sliding frame. The first and second sliding frames move independently inside of a mounting frame. A motor rotates a pair of vertical threaded rods to drive the first sliding frame and cause the first sliding frame to rise and fall. A belt and pulley configuration transfers an elevating force from the first sliding frame to the second sliding frame. The second sliding frame includes supporting bars and is elevated to place the display at a desired height and is retracted to conceal the display in a cabinet, or the like.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a device for lifting and lowering visual displays, such as television sets, video monitors, art pieces, flat plasma displays and the like. 
   2. Background of the Invention 
   The development of television technology has been very progressive, with television sets becoming very large and thin. The most recent aspect of this technology is thin, flat plasma TV displays. Since it is preferable to hide a display when not in use, there is a need for a lifting device, which would enclose a plasma display within any type of cabinet, and elevate the display above such cabinet. Existing devices are esthetically unsightly or impractical. For example, U.S. Pat. No. 6,494,150 provides a lift having a very heavy construction and does not provide a way of mounting the lift along its height. Since prior art lifts can only be attached at their base, they lack vertical stability and therefore are unlikely to be used successfully as a lift for a Plasma TV. Accordingly, a lift device is needed, which is compact, light, efficient, stable and safe. 
   BRIEF SUMMARY OF THE INVENTION 
   An aspect of the invention is to provide a simple, practical and safe design, which can work with different types and sizes of plasma displays. An embodiment of the present invention includes a sliding frame within a frame construction, where two frames slide independently inside or outside a third fixed frame. 
   An illustrative embodiment of the invention is designed to be light and compact. For example, it is possible to make the lift as thin as 1¾″ for lower weight visual displays and 2¼″ thick for heavy weight visual displays. A plasma TV or visual display may be mounted to the lift by two horizontally placed display-supporting bars. A mounting height of the bars may be adjustable. In an exemplary embodiment, the lifting device itself is mounted along its full height, to a back panel (e.g., ¾″ Veneer Core Plywood), which replaces an original furniture back. This is done because in many cases, the back of the furniture is made out of ¼″ thick MDF or Flake Board, for example, which doesn&#39;t provide enough stability to support the weight of a lift and the display. A further aspect of the invention is an achievement of horizontal and vertical stability, which is lacking in the prior art. In an embodiment, the stability is achieved by mounting the lift directly to a vertical surface along its full height. 
   The present invention is also highly efficient. In an exemplary embodiment, a small dimensioned 24VDC right angle gear motor is used, which is hidden inside the lift&#39;s enclosure. High efficiency is further achieved with the use of ball bearing slides and Teflon based lead screw nuts. Lifting action is provided, for example, with a combination of ¾″ lead screws, chains or belts and pulleys or roller chain sprockets. 
   According to an exemplary embodiment, all working parts are fully housed inside the lift&#39;s enclosure and not accessible by user. It is further contemplated that the lift doesn&#39;t have any horizontally placed parts, which could create a cutting action. These features dramatically decrease the chance of injury by a user or child, while the lift is in action, making the present invention a much safer construction than prior lifts, which did not offer a way of enclosing all working parts. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is top view of a single screw exemplary embodiment; 
       FIG. 2  is a front view of an exemplary embodiment in a lowered position; 
       FIG. 3  is front view of an embodiment in an elevated position; 
       FIG. 4  is front view of an exemplary embodiment in an elevated condition; and 
       FIG. 5  is front view of an exemplary embodiment in a lowered condition. 
   

   DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
   Referring now to the  FIGS. 1–3 , an elevating apparatus  1  is shown having a pair of lift-mounting brackets  2  mounted to a mounting panel  3 , and a pair of outer slide members  4  attached to the lift-mounting brackets  2 . A horizontal motor-mount bar  6  is attached to the lift-mounting brackets  2 , and a single shaft right angle gear motor  7  is mounted to the motor-mount bar  6 . A single vertical threaded rod  8  is mounted to a shaft of gear motor  7 . Two pairs of inner slide members  9  are attached to a back panel  10 . Ball bearings  5  are disposed between the inner slide members  9  and the lift-mounting brackets  2 . A horizontal bar  11  is attached to the back panel  10 . A single threaded nut  12  is mounted on the vertical threaded rod  8  and attached to the horizontal bar  11 . A sprockets/pulleys-bar  13  is attached to the back panel  10 . A pair of sprockets/pulleys  14  are attached to the sprockets/pulleys-bar  13  of the back panel  10 . A pair of chains/belts  15  are mounted on the sprockets/pulleys  14  where each is attached to the motor-mount bar  6  at one end and to a horizontal bar  19 , attached to the front panel  16  at the other end. A pair of outer slide members  17  is attached to the front panel  16  and ride on ball bearings  18 . Two display-supporting bars  20  are mounted to the front panel  16 . 
   In operation, the single shaft gear motor  7  rotates the vertical threaded rod  8 . The single threaded nut  12  on the rod  8  is attached to a sliding inner frame  24 . The sliding inner frame  24  comprises the back panel  10 , the four inner slide members  9 , the horizontal bar  11 , the sprockets/pulleys-bar  13  and the threaded nut  12 . The threaded nut  12  is mounted on the threaded rod  8  and attached to the horizontal bar  11 . Rotation of the threaded rod  8  causes the threaded nut  12  and sliding inner frame  24  to rise and fall under control of the motor  7 . 
   An exemplary additional lifting mechanism is provided that includes the two sprockets/pulleys  14  and the two chains/belts  15 , which causes a sliding outer frame  26  with the display-supporting bars  20  to elevate or lower to a height above the height of the retracted apparatus for concealment in shorter cabinet. The front panel  16 , two outer slide members  17  and the horizontal bar  19  constitute the sliding outer frame  26 . 
   As shown in  FIG. 4  an exemplary embodiment further provides for a pair of lift-mounting brackets  2 ′ to be mounted to a mounting panel  3  ( FIG. 1 ), and a pair of outer slide members  4 ′ to be attached to the lift mounting brackets  2 ′. Ball bearings having the same structure as the ball bearings  5  in  FIG. 1  are disposed between the inner slide members  9 ′ and the lift-mounting brackets  2 ′. A horizontal motor-mount bar  6 ′ is attached to the lift-mounting brackets  2 ′, and a double shaft-right angle gear motor  7   a  is mounted to the motor-mount bar  6 ′. A vertical threaded rod  8 ′ is mounted to one end of the double shaft gear motor  7   a , and the vertical threaded rod  8   a  is mounted inside the motor-mount bar  6 ′. Two pairs of inner slide members  9 ′ are attached to a back panel  10 ′. A horizontal bar  11 ′ is also attached to the back panel  10 ′. A pair of threaded nuts  12   a  are mounted on the vertical threaded rods  8 ′,  8   a  and are attached to the horizontal bar  11 ′. A sprockets/pulleys-bar  13 ′ is attached to the back panel  10 ′, and a pair of sprockets/pulleys  14 ′ are attached to sprockets/pulleys-bar  13 ′. A pair of chains/belts  15 ′ are mounted on the sprockets/pulleys  14 ′ and each is attached to the motor-mount bar  6 ′ at one end and to a horizontal bar  19 ′ at the other end. A pair of outer slide members  17 ′ is attached to the front panel  16 ′ and ride on ball bearings having the same structure as the bearings  18  in  FIG. 1 . A pair of display-supporting bars  20  ( FIG. 2 ) are to be mounted to the front panel  16 ′. A pair of sprockets  21  are provide such that one is attached to the shaft of double shaft motor  7   a  and other is attached to vertical threaded rod  8   a . A chain  22  connects the pair of sprockets  21 . 
   In operation, the double shaft gear motor  7   a  rotates the pair of vertical threaded rods  8 ′,  8   a  at the same rate through the set of sprockets  21  and the connecting chain  22 . A first sprocket is attached to one end of double shaft gear motor  7   a , and a second sprocket is attached directly to the second threaded rod  8   a . The two sprockets are connected with the chain  22  to rotate rods in synchrony. The two threaded nuts  12   a  on the rods  8 ′, 8   a , are attached to a sliding inner frame  24 ′. The sliding inner frame  24 ′ comprises the back panel  10 ′, four inner slide members  9 ′, the horizontal bar  11 ′, the sprockets/pulleys-bar  13 ′ and the two threaded nuts  12   a . The threaded nuts  12   a  are mounted on the threaded rods  8 ′,  8   a  and are attached to the horizontal bar  11 ′. Synchronous rotation of the threaded rods  8 ′,  8   a  causes the threaded nuts  12   a  and the sliding inner frame  24 ′ to rise and fall under control of the motor  7   a.    
   An exemplary additional lifting mechanism is provided that includes the two sprockets/pulleys  14 ′ and the two chains/belts  15 ′ and causes a sliding outer frame  26 ′ with the display-supporting bars  20  ( FIG. 2 ) to elevate or lower to a height above the height of the retracted apparatus for concealment in shorter cabinet. The sliding outer frame  26 ′ comprises the front panel  16 ′, the two outer slide members  17 ′ and the horizontal bar  19 ′. 
   A further exemplary embodiment is shown in  FIG. 5  that includes an elevating apparatus  1   b . A pair of lift-mounting brackets  2 ″ are mounted to a mounting panel  3  ( FIG. 1 ), and a pair of outer slide members  4 ″ are attached to lift mounting brackets  2 ″. Ball bearings are provided in the same manner as shown in  FIG. 1 . A horizontal motor-mount bar  6 ″ is attached to the lift-mounting brackets  2 ″ and a double shaft-right angle gear motor  7   a ′ is mounted to the motor-mount bar  6 ″. A vertical threaded rod  8 ″ is mounted to one end of the double shaft gear motor  7   a ′. A vertical threaded rod  8   a ′ is mounted inside the motor-mount bar  6 ″. Two pairs of slide members  9 ″ are attached to a back panel  10 ″ and a horizontal bar  11 ″ is also attached to the back panel  10 ″. A pair of threaded nuts  12   a ′ are mounted on the threaded rods  8 ″,  8   a ′ and attached to the horizontal bar  11 ″. A pair of sprockets/pulleys  14 ″ are attached to the front panel  16 ″ and a pair of chains/belts  15 ″ are mounted on the sprockets/pulleys  14 ″ such that the pair of chains/belts  15 ″ are respectively attached to the motor-mount bar  6 ″ at one end and to the horizontal bar  11 ″ at the other end. A pair of outer slide members  17 ″ are attached to the front panel  16 ″ and ride on ball bearings, as in  FIG. 1 . A pair of display-supporting bars  20  ( FIG. 2 ) are to be mounted to the front panel  16 ″. A pair of sprockets  21 ″ are provided such that one sprocket is attached to a shaft of the double shaft motor  7   a ′ and the other is attached to the vertical threaded rod  8   a ′. A chain  22 ″ connects the pair of sprockets  21 ″. 
   In operation, the double shaft gear motor  7   a ′ rotates the pair of threaded rods  8 ″,  8   a ′ at the same rate through the set of sprockets  21 ″ and the connecting chain  22 ″. The first sprocket is attached to one end of the double shaft gear motor  7   a , and the second sprocket is attached directly to the second threaded rod  8   a ′. The two sprockets  21 ″ are connected with the chain  22 ″ to rotate the rods  8 ″,  8   a ′ in synchrony. The two threaded nuts  12   a ′ on the rods  8 ″, 8   a ′ are attached to a sliding inner frame  24 ″. The sliding inner frame  24 ″ comprises the back panel  10 ″, the four inner slide members  9 ″, the horizontal bar  11 ″ and the two threaded nuts  12   a ′. The threaded nuts  12   a ′ are mounted on the threaded the rods  8 ″,  8   a ′ and are attached to the horizontal bar  11 ″. Synchronous rotation of the threaded rods  8 ″, 8   a ′ causes threaded nuts  12   a ′ and the sliding inner frame  24 ″ construction to rise and fall under control of the motor  7   a′.    
   An additional lifting mechanism comprising the two sprockets/pulleys  14 ″ and the two chains/belts  15 ″ cause a sliding outer frame  26 ″ with the display-supporting bars  20 , to elevate to a desired height or retract for concealment in a shorter cabinet. The sliding outer frame  26 ″ comprises the front panel  16 ″, the two outer slide members  17 ″ and horizontal bar  19 ″. 
   An aspect of the invention is a three-frame system including a frame-within-a-frame design, where two frames slide independently inside of a third one. Moreover, for vertical guides, a combination of ball bearing slides with an open track is used. The frame-within-a-frame construction that uses the open truck slides provides a means to allow an over-extending lift to be attached along its full height. 
   An exemplary embodiment employs standard industrial, rolled coil steel, and a ball bearing slide, in an open truck design. However, it will be understood that any type of slide or vertical guide with an open track design, which provides ability for a frame-within-frame-construction, could be used. The arrangement or the description of the frames or slides may be changed. Therefore, it will be understood that the invention may be embodied otherwise than as herein specifically illustrated or described and that certain changes in form and arrangement of parts and the specific manner of practicing the invention may be made within the underlying idea or principles of the invention. 
   In addition, if the lift is used in pairs with a platform attached in between, it could lower large dimensional objects, such as video projectors and regular TV sets.