Abstract:
A work platform height adjustment apparatus having a frame and a support assembly moveably mounted on the frame. The frame is provided with cover panels which are mounted to the frame and the support assembly carries a spring biased work platform on brackets mounted to the support assembly so that the work platform can assume a number of fixed height positions.

Description:
RELATED APPLICATIONS 
     This is a utility patent application claiming priority and benefit from U.S. Provisional Patent Application No. 62/170,776, filed Jun. 4, 2015. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     REFERENCE TO SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX 
     None. 
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention is directed to a wall mounted adjustable work platform having adjustable elevation. Such a device improves work force productivity and reduces strain associated with prolonged sitting and/or standing. 
     2. Description of the Prior Art 
     In our current computer oriented society, large numbers of people find themselves sitting at a desk or workstation for extended periods of time. This has resulted in a variety of work related injuries and loss of productivity. There have also been numerous studies conducted over the past several years that have identified serious health risks associated with prolonged sitting. These include the risks of high blood pressure, cardiovascular disease, diabetes and obesity as well as back pain and strain. 
     Studies have also shown that alternating between sitting and standing throughout the day helps to reduce these risks, reduces general fatigue and increases productivity. 
     The drawing shown in  FIG. 1  shows a prior art height adjustable table currently being used. Telescoping legs provide 18″ to 20″ height adjustment and a horizontal member connects and synchronizes the movement of the two legs. The telescoping leg design is expensive, restricts the design appearance of the table legs, and cannot be easily reduced in size for wall or office panel attachment. 
     The ideal height work surface height range is 27″ for a low sit-down position and 47″ for stand-up position which is a 20″ adjustment range. Designing a telescoping leg mechanism to meet this adjustment range is difficult and requires using every inch of space inside the telescoping tubes. Adapting this mechanical concept to panel mounted surfaces results in a telescoping leg almost 27″ in height, which is why freestanding adjustable tables are used. 
     Typically a non-adjustable work surface in an open office work space is attached directly to the panel without support legs. This keeps the knee space under the surface open for easy user leg movement, easier floor cleaning (because there are no table legs), and a cleaner, uncluttered looking work space. The problem is that changing the work surface height requires manually removing and reinstalling the surface at a different height. 
     The drawings shown in  FIGS. 1 and 2  shows how freestanding height adjustable tables are currently used in a typical open office work space. This is an expensive solution to the problem and violates many advantages offered by panel created office spaces. 
     Another adjustable work surface table presently in the marketplace is the Hack product by Vitra which uses a pulley system tied to a crank. The belts, which form the pulley system, are tightened by cranks which tighten or loosen the belts to adjust the work station platform surface up and down. The table is free standing and can be folded up into a box or flat cabinet for storage or moving. 
     Representative adjustable work surfaces shown in the prior art are U.S. Pat. No. 4,926,760 issued May 22, 1990 which discloses a self-leveling table having a pair of scissor arms pivotally mounted on the table. The scissor arms are restraining from closing by a set of adjustable springs and U.S. Patent Application Publication Number 2004/0040480 having a publication date of Mar. 4, 2004 which discloses a height adjustable table top using a scissoring support assembly mounted in tracks formed in the table top frames and the support frame. 
     The present invention overcomes these problems by providing a wall mountable adjustable height work platform which is spring assisted to allow easy adjustment. 
     SUMMARY OF THE INVENTION 
     The present invention addresses the ergonomic need to easily adjust the height of a work platform from a sit-down use position to a stand-up position to promote blood circulation and relieve user back pain. Since people are of different sizes there is a need to adjust the work surface height for the use of different people which allows multiple people to have a tailored work site. A work platform is defined as any horizontal surface that must remain level during and after the height is adjusted. The invention utilizes a frame having a moveable support assembly which carries the work platform and moves vertically on slide rods mounted to the frame. The support assembly has a plurality of continuous force springs mounted thereon which are also connected to the frame to provide a force assist to the work platform. 
     It is a principal object of this invention to provide a height adjustable work platform with a planar surface that will move up or down to accommodate the smallest seated individual employee and then rise up to accommodate the tallest standing individual employee. 
     It is another object of the invention that the height adjustment of the work surface platform is assisted by a spring assembly. 
     It is yet another object of the invention to provide a height adjustable wall mounted work platform assembly which can be easily attached to a wall or room panel or mounted inside a wall or room panel. 
     It is still another object of the invention to provide a simply constructed work platform with a height adjustable work surface. 
     It is another object of this invention that the work platform is user controlled and manually operated so that the work platform adjusts quickly to various up and down heights without the use of expensive electric motors or cumbersome manual cranks. However, an electric motor can easily be installed to make the platform move up and down. 
     It is a still further object of this invention that the spring assist can be variably located to counterbalance different platform weights. 
     It is another feature of this invention that the work platform provides maximum legroom underneath for seated positions and requires minimum use of office space in the standing position. 
     These and other objects, advantages, and novel features of the present invention will become apparent when considered with the teachings contained in the detailed disclosure along with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be described with reference to the appended Figures, in which: 
         FIG. 1  is a perspective view of an elevatable prior art telescoping table; 
         FIG. 2  is another perspective view of an elevatable prior art telescoping table; 
         FIG. 3  is a front perspective view of the inventive continuous force spring height adjustable work platform with a panel background; 
         FIG. 4  is a rear perspective view of the height adjustable work platform of  FIG. 3 ; 
         FIG. 5  is a perspective view of the height adjustable work platform shown in  FIG. 3  with the work platform, one side panel and middle panel removed; 
         FIG. 6  is an opposite side perspective view of the height adjustable work platform shown in  FIG. 5 ; 
         FIG. 7  is a partial enlarged rear view of the height adjustable work platform shown in  FIG. 4 ; 
         FIG. 8  is an enlarged partial view of  FIG. 7 ; 
         FIG. 9  is an enlarged partial view of another embodiment showing additional continuous force spring assemblies connected directly to upper cross member of the apparatus frame; 
         FIG. 10  is a perspective view of the invention mounted on a wall; 
         FIG. 11  is a perspective view of the invention mounted to a panel of a modular office cubical; and 
         FIG. 12  is a perspective view of the invention with curved work platforms mounted on curved panels. 
     
    
    
     DESCRIPTION OF THE INVENTION 
     The present invention is directed towards a height adjustable work platform apparatus and the preferred embodiment and best mode of the invention is shown in  FIGS. 3 through 9 . 
       FIGS. 4 through 9  disclose a frame  12  of the adjustable work platform apparatus with two parallel upright L-shaped standards  14  and  16 . As shown in  FIG. 6 , an upper cross member  18  is secured to the top of standards  14  and  16  and a lower bottom cross member  20  is secured to the bottom of the upright standards  14  and  16 . The standards and cross members can be welded together, glued or fastened together with conventional fasteners. This frame  12  can be installed on an office panel (see  FIG. 11 ), on a wall (see  FIG. 10 ) or it can be independent to hang on the outside of an office panel by various means (hooks on frame, hang over the top of a panel; attached to a wall). 
     A moveable work platform support assembly  21  has two middle parallel cross support members  22  and  24  which extend between the upright standards  14  and  16  and are slidably mounted on slide rods  26  and  28 . Slide rods  26  and  28  are mounted in throughgoing holes  25  cut in cross members  22  and  24  and the slide rods are secured to the upper cross member  18  and the lower cross member  20 . Support plates  30  and  34  are fixedly secured to cross members  22  and  24  by welding, fasteners or other means to hold the cross members  22  and  24  in a fixed position and hold work platform brackets. Each support plate is provided with a pair of aligned linear bearing assemblies secured thereto ( 31 ,  32 ), ( 35 ,  36 ). The linear bearings assemblies  31 ,  32  and  35 ,  36  are securely mounted to the respective support plate as shown in  FIG. 4 . Slide rod  26  is slidably mounted in linear bearings assemblies  31 ,  32  and slide rod  28  is slidably mounted in linear bearings assemblies  35 ,  36 , allowing the cross support members  22  and  24  and the support plates  30  and  34  to slide up and down slide rods  26  and  28 . Extending outwards perpendicularly from each of the support plates  30  and  34  are work platform brackets  40  and  44 , respectively. The platform brackets are secured to the support plates by welding if metal or integrally molded if plastic. Alternatively, they may be mounted in slots cut into the support plates or secured by fasteners to the support plates. Each of the work platform brackets  40  and  44  has a planar top surface  46  upon which the work platform  50  is seated as shown in  FIGS. 3 and 6 . 
     As seen in  FIG. 3 , two side panels  80  and  82  are mounted on the front of the frame  12  on the side of work platform brackets  40  and  44 . A middle panel  85  is mounted adjacent the interior surface of work platform brackets  40  and  44  defining a vertical gap  81  and  83  which allow the work platform brackets  40  and  44  to move along and through when the work platform  50  is moved upward or downward. Thus, the work platform  50  is held in placed by each of the continuous force spring assemblies which form a spring assistance for lowering and raising the work platform  50 . 
     The work platform  50  has a planar upper surface  52  and is preferably rectangularly shaped as is clearly shown in  FIGS. 3 and 10 . When used on a curved wall  110  as shown in  FIG. 12 , the work platform  112  has a curved inner surface to fit the contour of the curved wall. The work platform  50  can be clipped to the brackets  40  and  44  or mounted to the platform  50  with fasteners such as screws as is well known in the art. Spring assemblies  60 , each comprising a continuous force spring  62  mounted inside a spring housing  64 , are secured to the bottom of cross member  22  as seen in  FIG. 6 . In  FIG. 5 , each free end  63  of the continuous force spring  62  is secured to a cylindrical mount  66  having a throughgoing cylindrical bore  67  which is mounted around a cylindrical support bar  68 . The cylindrical support bar  68  is in turn mounted to end supports  69  which are secured to the upper cross member  18  as most clearly shown in  FIGS. 5 and 6 . The continuous force spring  62  extends through a rectangular opening  23  cut in rectangular cross member  22  as is most closely shown in  FIG. 6 . An alternate means of securing the free end  63  of the spring  62  is shown in  FIG. 9 . In  FIG. 9 , the end of  63  of the continuous force spring  62  is secured to an eyelet  65  secured to the upper cross bar  18 . 
     A brake mechanism  70  as seen in  FIGS. 8 and 9  comprising a spring  72  ( 73 ) and plates  74  ( 75 ) and a brake release cable  76  ( 77 ) is used to hold the work platform  50  in place. 
     The present wall mounted design offer work surface adjustment with the following features:
         Low cost because of minimal parts   Work surface is strong and stable   Can attach to any wall or office panel   No safety issues because mechanism is covered       

     Adding Energy to Lift Work Surface 
     The ideal surface with adjustable height requires minimal force for the user to lift the work platform surface  52  to a new position. This is accomplished by using mechanical springs, to lift the weight of the work platform plus any working load. 
     In the wall mounted embodiment shown in  FIG. 10 , the continuous force springs connected to the stationary top rail  68  of the frame will exert a force to pull the work platform  50  up. 
     Stopping the Work Surface at any Position 
     As the work surface height is adjusted a brake  70  is needed to hold the work platform surface  52  in the desired position. 
     The brake  70  works well when the work surface load is counter balanced by the continuous force spring assembly. While, two different brake assemblies have been described, there are countless manual brake designs ranging from simple pin-in-a-hole designs, rack and pinion, gears and brake pad designs. The mechanical brake can be located at any point that prevents the linkage from moving. 
     As seen in  FIG. 10 , the invention can be used as a simple wall mount  90  while  FIG. 11  shows use of the invention  100  in a cubicle.  FIG. 12  shows use of the invention  110  with a curved work platform  112  on curved panels. 
     The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. However, the invention should not be construed as limited to the particular embodiments which have been described above. Instead, the embodiments described here should be regarded as illustrative rather than restrictive. Variations and changes may be made by others without departing from the scope of the present invention as defined by the following claims: