Abstract:
An apparatus adaptable to automatic leveling platform devices with integral springs, which enables an operator to easily and quickly adjust the overall spring resistance to accommodate a range of loads applied to the platform. More particularly, the apparatus utilizes a sliding frame, springs and pins such that a user may engage or disengage one or more springs easily and quickly.

Description:
BACKGROUND 
       [0001]    1. Field of the Invention 
         [0002]    The present invention pertains to a variable level platform elevator adjustment mechanism and, more particularly, to an adjustment mechanism which can be mounted within or inserted into a plurality of carts, palette loaders, truck bins, parts bins and any device that utilizes a variable level platform elevator with an integral elastic means such as springs. 
         [0003]    2. Background 
         [0004]    Vertical leveling platform devices for maintaining objects at a vertical position are well known in the art. These devices utilize a platform assembly and an elastic lifting means, typically a set of springs. Moreover, these devices enable an operator or user to load or remove objects from a set distance above a surface without unnecessary bending and strain on the neck, back and shoulders. Thereby reducing the risk of injury and increasing operator productivity. 
         [0005]    As further background, vertical leveling platform devices typically utilize calibrated springs as a lifting means in order to adjust the vertical height of objects on a platform. The springs are calibrated or chosen to correspond to the weight of the objects on the platform. The spring constant of the spring (the spring constant “k” in the equation F=kx, where “F” equals the force supplied by the spring and “x” equals a spring displacement distance) is selected so that the weight of the objects removed will cause the platform to move through a distance “x”. The distance “x” is also essentially equal to the height of the objects being removed from the platform. The force (“F”) supplied by the spring causes the platform to rise to a height generally equal to the height of the objects removed. Through this mechanism, the spring keeps the objects at the proper height, so that an operator does not have to provide input to keep the objects at a proper vertical adjustment. 
         [0006]    Through the same mechanism, the vertical leveling platform lowers the objects as additional objects are added to the platform in order to keep the objects on the platform in a vertical position that minimizes the bending required to remove an object from the platform. As objects are removed from the platform, the variable level platform device raises the level of the objects on the platform so that the objects remaining on the platform maintain the vertical position that minimizes the bending required to remove an object from the platform. 
         [0007]    A problem commonly encountered with vertical leveling platforms is that they do not provide a quick and easy way to adjust the lifting force provided by the springs in order to accommodate different sized objects in transition to and from the platform. More particularly, they do not provide the operator with an easy way to engage or disengage each individual spring or elastic means. For the foregoing reasons, it is apparent that there is a need for a mechanism that enables an operator to quickly and easily engage or disengage said elastic means in order to provide the proper lifting force on vertical leveling platform devices. This would reduce equipment downtime and improve operator efficiency and safety. 
         [0008]    The present invention provides a device for reducing these problems. The difficulties inherent in the art are therefore overcome in a way which is simple and efficient, while providing better and more advantageous results. 
       SUMMARY 
       [0009]    In accordance with the invention, an adjustment mechanism is provided to adapt to a variable level platform elevator such that an operator can easily and quickly increase or decrease the overall lifting force by engaging or disengaging a select number of elastic means, typically springs. 
         [0010]    The adjustment mechanism comprises a first frame assembly and a second frame assembly. The first frame assembly comprises an engaged support means. The second frame assembly comprises a disengaged support means and a connection member. The frame assemblies are connected such that they move towards and away from each other within and along the same plane. An elastic lifting means is provided by one or more elastic means or springs with a first end and a second end. The first end is operatively connected to the second frame connection member and said second end has the ability to operatively engage either the first frame assembly engaged support means or to operatively engage the second frame assembly disengaged support means. This enables an operator to easily and selectively increase or decrease the tension force applied between the first and second frame assembly by engaging or disengaging one or more elastic means with the engaged support means. The non-engaged elastic means, by default, operatively connect to, or rest on the disengaged support means. 
         [0011]    In an embodiment of the invention, the adjustment mechanism may utilize a unique and inventive fastening bracket that attaches to the second end of the elastic means which has the ability to either operatively engage the first frame assembly engaged support means or to operatively engage the second frame assembly disengaged support means. 
         [0012]    The adjustment mechanism can be made portable, adaptable, or permanent to a plurality of carts, palette loaders, truck bins, parts bins and any device that utilizes a variable level platform elevator with integral elastic mean such as springs. Particularly, it can be outfitted to meet the needs of the manufacturing and merchandising industries. 
         [0013]    Still other benefits and advantages of the invention will become apparent to those skilled in the art to which it pertains upon a reading and understanding of the following detailed specification. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where: 
           [0015]      FIG. 1A  is a platform raised perspective view of an apparatus embodying features of the present invention. 
           [0016]      FIG. 1B  is a platform fully loaded view of an apparatus embodying features of the present invention. 
           [0017]      FIG. 1C  is a platform fully loaded view of an apparatus embodying features of the present invention. 
           [0018]      FIG. 2  is a front elevated view of an apparatus embodying features of the present invention in the default position. 
           [0019]      FIG. 3  is a side cut-a-way close-up of the non-engaged engagement bracket. 
           [0020]      FIG. 4  is a side cut-a-way close-up of the engaged bracket. 
           [0021]      FIG. 5  is a close-up of spring and engagement bracket. 
           [0022]      FIG. 6  is a front close-up view of spring and engagement bracket. 
           [0023]      FIG. 7  is a side close-up view of spring and engagement bracket. 
           [0024]      FIG. 8  is a platform raised perspective view of an embodiment of the invention installed in a tote cart. 
           [0025]      FIG. 9  is a back elevated view of an embodiment of the invention installed in a tote cart in the default position. 
           [0026]      FIG. 10  is a back elevated view of an embodiment of the invention installed in a tote cart in the fully loaded position. 
           [0027]      FIG. 11  is a platform raised perspective view of an embodiment of the invention installed in a pallet cart. 
           [0028]      FIG. 12  is a rear elevated view of an embodiment of the invention installed in a pallet cart. 
           [0029]      FIG. 13  is a perspective view of the invention installed in a pallet cart depicting objects on the platform. 
       
    
    
     DESCRIPTION 
       [0030]    Referring now to the drawings wherein the showings are for purposes of illustrating a preferred embodiment of the invention only and not for purposes of limiting the same, the present invention is a mechanism for easily increasing or decreasing the resistance of a downward load on a variable platform elevator which maximizes operators efficiency and ease of use. 
         [0031]    With reference to  FIGS. 1A ,  1 B,  1 C,  2  and  3 , an embodiment  100  of the present invention comprises an inner vertical frame assembly  102  and an outer vertical frame assembly  104 . The inner vertically frame assembly  102  is moveable within the outer vertical frame assembly  104 . One or more elastic means  106  are provided to lift inner vertical frame assembly  102  within outer vertical frame assembly  104 . First embodiment  100  further comprises a platform  108  which is rigidly attached generally horizontal and perpendicular to the inner vertical frame assembly  102 . 
         [0032]    The outer vertical frame assembly  104  comprises guide rods  110  and  112  vertically disposed and fixedly connected by horizontal cross member  114 . An engagement support means is provided, engaged support member  116  which is mounted below and horizontal to the cross member  114 . The engaged support means can be any elongated support that maintains the ability to engage and support the elastic means  106 . It will be generally known that in other embodiments cross member  114  and engaged support member  116  may be one in the same. Engaged support member  116  comprises an optional vertical guide bracket  118  and a plurality of engagement openings  120  which can be a hole, slot, or any other means adaptable to receive a fastening means or removable pin  122 . When a vertical guide bracket  118  is included in the adjustment mechanism, engagement openings  120  pass through both engaged support member and vertical guide bracket  118 , thus allowing said pin  122  to pass through allowing it to be easily removed or inserted. Vertical guide bracket  118  is depicted up close in  FIG. 3  and comprises an elongated channel  124  with a vertical engagement member slot  126 . 
         [0033]    The inner vertical frame assembly  102  comprises deck guides  128  and  130  vertically disposed for receiving guide rods  110  and  112  Inner vertical frame assembly  102  further comprises a disengage support means, disengaged support member  132  and a connection member  134 . The disengaged support means can be any elongated horizontal support that maintains the ability to engage and support the elastic means  106  when elastic means is disengaged from engaged support member  116 . Disengaged support member  132  comprises, for purposes of this embodiment, two horizontally disposed parallel brackets  136  and  138 . The horizontally disposed parallel brackets  136  and  138  are spaced a sufficient distance apart such that the elastic means  106  pass unhindered between them. It will be known that disengaged support member  132  may be configured in any way that supports the spring in the disengaged position. The horizontally disposed parallel brackets  136  and  138  are preferred because of its favorable functionality, however not required in all versions of the invention. 
         [0034]    Referring to  FIG. 1C , the one or more elastic means, springs  154 ,  156 ,  158  and  160  have first ends  162 ,  164 ,  166  and  168  and second ends  170 ,  172 ,  174  and  176 . First ends  162 ,  164 ,  166  and  168  are operatively connected to the connection member  134 . The second ends  170 ,  172 ,  174  and  176  are attached to an engagement means, fastening brackets  178 . The engagement means can be any bracket configuration that has the ability to engage either the engagement support means or to engage or be supported by the disengaged support means. With that said, fastening bracket  178  is adapted to either engage engaged support member  116  by pin  122  or resort to a default resting position on disengaged support member  132  comprising the horizontally disposed parallel brackets  136  and  138 . 
         [0035]    A constant elastic means, constant springs  140  and  142  are provided having first ends  144  and  146  and second ends  148  and  150 . First ends  144  and  146 , are operatively connected to the connection member  134  and second ends  148  and  150  are operatively connected to the engagement support member  116 . Constant springs  140  and  142  are optionally provided as an elastic means to ensure a constant and minimal lifting force on inner vertical frame assembly  102  within outer vertical frame assembly  104  to ensure that adjustment mechanism always returns to its default position as discussed below. It will be known that the addition of constant elastic means are an optional feature and are not essential to the invention. 
         [0036]      FIGS. 3 ,  4 ,  5 ,  6  and  7 , show an embodiment of an engagement means, engagement bracket  178  which comprises a frame assembly  184  with four vertical sides  186  with a top  192  and bottom  194  that form a hollow rectangular configuration. Frame assembly  184  further comprises a means for engaging a horizontal support means, a first pair and second pair of horizontally aligned slot openings  188  and  190  near bottom  194  of said frame assembly  184  which are adapted to securely receive and embrace the horizontally disposed parallel brackets  136  and  138  depicted in  FIGS. 1A , B, and C. Engagement bracket  178  further comprises a vertical engagement member  180  with engagement opening  182 . Vertical engagement member  180  is affixed near the top  192  of the frame assembly  184 . The engagement bracket  178  is attached to an elastic means, spring  196  by a fastening means  198 . 
         [0037]    Referring to  FIGS. 1-7 , the operation of the embodiment  100  will be explained.  FIG. 1A  depicts the first embodiment in a default position whereby no downward force is being applied to platform frame  108  or inner vertical frame assembly  102 . Embodiment maintains tendency to achieve default position by way of the constant and minimal lifting force provided by constant springs  140  and  142 . While in the default position, operator may optionally engage or disengage springs  154 ,  156 ,  158  and  160  by inserting pins  122  in desired corresponding engagement openings  120  thereby incrementally increasing or decreasing the resistance applied to inner vertical frame assembly  102 . This provides the operator the ability to select the proper level of resistance for a specific load on the platform  108 . 
         [0038]    Once the proper resistance is selected to accommodate the specified load, first embodiment  100  is ready for operative use. During operation, the platform lowers as objects are added to the platform in order to keep the objects on the platform in a vertical position that minimizes the bending required to remove an object from the platform. Transversely, as objects are removed from the platform, first embodiment  100  raises the level of the objects on the platform so that the objects remaining on the platform maintain the vertical position that minimizes the bending required to remove an object from the platform. More specifically, while the load increases on the platform  108 , the level of the platform lowers approximately the height of the object added and when the load on the platform  108  decreases, the platform raises approximately the height of the object removed. When no load is applied to platform  108  the first embodiment  100  returns to the default positions as depicted in  FIG. 1A . 
         [0039]      FIGS. 1B and 1C  depict the embodiment  100  in operative use whereby a downward force is being applied to the platform frame  108  and the inner vertical frame assembly  102 . As depicted, elastic means, springs  154  and  156  are in the engaged position secured by pins  122  and fastening bracket  178  further detailed in  FIG. 4 . Springs  158  and  160  are depicted in the disengaged position whereby engagement bracket  178  is not being secured by pins  122 , but are engaged to or resting upon disengaged support member  132  partially depicted by  FIG. 3 . More particularly, the first and second pair of horizontally aligned slot openings  188  and  190  in the frame assembly  184  embrace and overlay upon the horizontally disposed parallel brackets  136  and  138  while maintaining position by the minimal tension of springs  158  and  160 . 
         [0040]      FIGS. 8 ,  9  and  10 , depict a tote cart  200  which utilizes and contains the inventive concept. Tote Cart  200  comprises an inner vertical frame assembly  202  and an outer vertical frame assembly  204 . The inner vertically frame assembly  202  is moveable within the outer vertical frame assembly  204 . Elastic means, springs  206  are provided to lift inner vertical frame assembly  202  within outer vertical frame assembly  204 . Tote cart  200  further comprises a platform  208  which is rigidly attached generally horizontal and perpendicular to the inner vertical frame assemblies  202 . 
         [0041]    Tote cart  200  comprises springs  206  which ends are operatively connected to the connection member  234  and fixedly attached to the fastening brackets  278 . Fastening brackets  278  are adapted to either engage engaged support member  216  by a pin or other means or revert to a default position resting on disengaged support member  232 . 
         [0042]    Tote cart  200  further comprises optional constant springs  240  which are operatively connected to the connection member  234  and to the engagement support member  216 . Constant springs  240  coupled with a hydraulic lifting means, hydraulic  280  are provided to ensure a constant and minimal lifting force on inner vertical frame assembly  202  within outer vertical frame assembly  204  whereby inner frame assembly  202  and platform  208  will revert to the default position when cart is not loaded as depicted in  FIGS. 8 and 9 . 
         [0043]      FIGS. 11 ,  12  and  13 , depict a palette cart  300  which is yet another example of the utilization of the inventive concept. Palette cart  300  comprises an inner vertical frame assembly  302  and an outer vertical frame assembly  304 . The inner vertically frame assembly  302  is moveable within the outer vertical frame assembly  304 . Elastic means, springs  306  are provided to lift inner vertical frame assembly  302  within outer vertical frame assembly  304 . Palette cart  300  further comprises a platform  308  which is rigidly attached generally horizontal and perpendicular to the inner vertical frame assemblies  302 . 
         [0044]    Palette cart  300  comprises springs  306  which ends are operatively connected to the connection member  334  and fixedly attached to the fastening brackets  378 . Fastening brackets  378  is adapted to either engage engaged support member  316  by a pin or other means or revert to a default position resting on disengaged support member  332 . 
         [0045]    Palette cart  300  further comprises optional constant springs  340  which are operatively connected to the connection member  334  and to the engagement support member  316 . Constant springs  340  are provided to ensure a constant and minimal lifting force on inner vertical frame assembly  302  within outer vertical frame assembly  304  without the need of engagement of springs  306  whereby inner frame assembly  302  and platform  308  will revert to the default position when cart is not loaded as depicted in  FIGS. 11 and 12 . 
         [0046]    Referring to  FIGS. 11 and 13 , palette cart  300  further comprises a rotating means  390  on platform  308  that has the ability to rotate a palette or other load placed on the platform  308  360 degrees. Palette  300  further comprises a vertical spindle  392  that is adapted to receive a roll of industrial wrapping  394  or other wrapping means. Referring to  FIG. 13 , as loads are incrementally increased and stacked on platform  308 , industrial wrapping  394  can be simultaneously applied and wrapped around the loads via spindle  392  and rotating means  390  as platform  308  descends to accommodate the load. 
         [0047]      FIGS. 8 and 11  depict the cart tote  200  and the palette cart  300  in the default position. In the default position, operator of the equipment may optionally engage or disengage springs  254  and  354  by way of fastening bracket  278  and  378 , thereby incrementally increasing or decreasing the resistance applied to inner vertical frame assembly  202  and  302 . This provides the operator the ability to select the proper level of resistance for a specific load on the platform  208  and  308 . 
         [0048]    All of the embodiments of the present invention can be made portable, adaptable, or permanent and fit to any size of a plurality of carts, palette loaders, truck bins, parts bins and any device that utilizes a variable level platform elevator with integral elastic mean such as springs. Particularly, it can be outfitted to meet the needs of the manufacturing and merchandising industries. 
         [0049]    The present invention can be made in any manner and of any material chosen with sound engineering judgment such as steel. The materials may be strong, lightweight, long lasting, economic, and ergonomic. 
         [0050]    The previously described versions of the present invention have advantages, including the ability to quickly and easily engage or disengage one or more elastic means in order to increase or decrease the applied force on the inner vertical frame and platform. Moreover, the disengaged support member allows disengaged springs to rest upon and easily be stowed in a disengaged position for quick and easy access for future needs. 
         [0051]    Although preferred embodiments of the invention have been described in considerable detail, other versions and embodiments of the invention are possible. For example, the invention could be configured to function properly with elements interchanged within the inner and outer frame assemblies. The outer frame assembly could comprise a connection member operatively connected to all of the elastic means and a disengaged support member there below. The inner frame assembly would only comprise the engagement support member. The configuration would allow the operator to operate the embodiment substantially as described above; however, the engagement support member and engaged elastic means with pins and the like would move with the inner frame as force is applied to the platform. Therefore, the present invention should not be limited to the preferred embodiments described herein, but instead is defined by the spirit and scope of the appended claims.