Abstract:
An system for assisting a user in unloading a hand cart is provided, including a rotatable handle for assisting the user in tilting the cart. The load is removed from the cart by tilting the cart forward, then pulling the cart out from under the tilted load. A spring-assisted handle mounted on the cart, which can be gripped and pulled by the user, assists the user in removing the load from the cart, in a simple and convenient manner.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a hand operated system for assisting in unloading a hand cart. More particularly, the present invention includes a hand cart with a rotatable handle for use in dislodging the load of a hand cart.  
           [0003]    2. Summary of Related Art  
           [0004]    Hand carts are well known in the material handling industry for loading and unloading material from trucks and trailers. Hands carts are used not only at truck loading docks, but also at retail establishments and other delivery points. Hand carts are also essential devices for moving loads within warehouses and production facilities. The primary construction of a hand cart includes two wheels on a single axle, two vertical frame members with cross frame members, a handle at the top of the frame, and a load engaging flange plate at the bottom of the frame.  
           [0005]    In normal use of the hand cart, the user will typically tilt the cart toward himself, thus stabilizing the load on the cart for transport. A majority of hand carts do not have any system assisting the removal of the load from the cart. Typically, the user will tilt the cart forward, opposite the direction of tilt during normal use, and then attempt to slide the load off of the cart. This can involve simply using gravity to slide the load off of the cart. This can be dangerous, as it tends to leave the load in an unstable position during removal from the cart. Additionally, the user will also tend to alternately pull on the opposing handles of the cart, in an attempt to “step” the cart out from underneath the load.  
           [0006]    Several assist systems for removal of load from hand carts are disclosed in the prior art. The hand carts of the prior art typically include either foot operated pedals operating mechanisms to displace the load, or hand operated handles engaging push plates to push the load off of the cart.  
           [0007]    In the prior art, Brandenburg (U.S. Pat. No. 5,624,224) utilizes a foot-operated, pivotably mounted, spring-biased handle operating a mechanism to displace the load from the hand cart. Fixed, non-rotatable handles are also known in the art.  
         SUMMARY OF THE INVENTION  
         [0008]    According to the present invention, there is provided a hand cart with a handle which can be pulled by the user to assist in unloading the hand cart. The handle is preferably mounted centrally on the hand cart, facing the user. The handle is preferably provided with a spring-assist mechanism to assist the user in tilting the cart, and to return the handle to a neutral position following the unloading of the cart.  
           [0009]    An object of the present invention is to provide a hand cart with a hand operated handle to assist in the removal of the load from the cart.  
           [0010]    Another object of the present invention is to provide a hand operated system for assisting the removal of the load from a hand cart that is mechanically simple and easy to use. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which:  
         [0012]    [0012]FIG. 1 is a perspective view of the rear of an upright hand cart with the unloading system mounted on the cart;  
         [0013]    [0013]FIG. 2 is a side perspective view of the hand cart showing the unloading handle in a partially depressed position; and  
         [0014]    [0014]FIG. 3 is an exploded view of the structure of the rotatable unloading handle. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0015]    In FIG. 1, a hand cart  10  includes upright members  12  with a load bearing member  14 , designed to be positioned beneath a load, and wheels  16  connected by an axle assembly  18 . A fixed handle  20  is connected to the supports  12  near the top of the supports  12 . The basic structure of hand carts is well known and variations are known within the filed, and are suitable for use with the present invention.  
         [0016]    According to an embodiment of the present invention, a rotatable handle  22  is attached to the upright members  12 . The rotatable handle  22  is attached to the members  12  at a point nearer the load bearing member  14  than the top of the members  12 . The rotatable handle  22  preferably includes a U-shaped bar  24  and a spring mechanism to return the handle to its “rest” position. The ease of unloading the cart  10  is increased by locating the rotatable handle  22  nearer the bottom of the members  12 , but placing the rotatable handle  22  too low increases the amount an operator must bend to grab the handle  22  and unload the cart. Therefore the location of the rotatable handle  22  must be balanced between ease of use-and maximization of benefit of unloading the cart.  
         [0017]    [0017]FIG. 2 illustrates the cart  10  in a partially reclined position, typical of a situation of transporting a load. The handle  22  is illustrated in a, partially depressed position, illustrative of the situation wherein the rotatable handle  22  has been gripped by an operator.  
         [0018]    To unload the cart  10 , a user could place one hand on the handle  20 , and the other hand on the rotatable handle  22 . By pressing the handle  20  in the direction D 1  and applying an opposing pulling motion on the rotatable handle  22  in the direction D 2 , the user will force the top of the cart  10  forward, causing the load to slide forward from the load bearing member  14  in the direction D 3 .  
         [0019]    While a fixed handle could conceivably be used in place of rotatable handle  22 , the use of the rotatable handle eases operation, and can decrease the physical force needed to unload the cart  10 , thus reducing the strength needed by a user to unload the cart  10  safely.  
         [0020]    The rotatable handle  22  can be connected to the upright members  12  in any manner allowing rotation of the handle  22 . A preferred method for connecting the rotatable handle  22  is shown in FIG. 3. In this embodiment a bolt  30  proceeds through a hole  32  in the upright member  12 . At least a portion of the bolt  30  is threaded. A spring device, in this embodiment a coil spring, is positioned next to the hole  32 , and the threaded bolt  30  extends through the coil of the spring  34 . The spring  34  allows the rotatable handle  22  to return to its upright position when the handle is not being pulled. Additionally, the spring  34  assists the user in unloading the cart  10 , by providing resistance against rotation of the handle  22 . Increasing the tension of the spring  34  increases the resistance against the user rotating the handle  22 , but assists the user in pulling the load bearing member  14  from under a load.  
         [0021]    In at least one embodiment of the present invention, a nut is then placed on the threaded bolt adjacent the spring  34 . On the opposing side of this nut is located an end  38  of the U-shaped member  24  of the rotatable handle  22 . The threaded bolt  30  extends through a hole  40  in the end  38 . Additionally, a mechanism can be provided to secure the spring  34  to the rotatable handle  22 . In the embodiment shown, a circular ring  42  is placed around the U-shaped handle. The ring can have a channel  44  attached, through which an arm  52  of the spring  34  passes. This secures the spring  34  to the rotatable handle  22 . Alternatively, the spring  34  can be connected to the handle  22  by any known means, including by merely positioning the arm of the spring  34  in such a manner that it rests securely against the arm  22 . Alternatively, the spring can be secured to the handle by welding, or any other known method of connection. The opposing arm  50  of the spring  34  can be connected to the upright member  12  of the cart either by a firm connection, e.g. welding, or by resting against the member  12 . As shown, the arm  50  of the spring  34  is positioned so that it is biased against an inside face of member  12 . On the opposing side of the end  38  of the handle  22  is preferably placed a washer  46 , followed by an end nut  48 , to secure the spring mechanism in place.  
         [0022]    While the embodiment shown pictures a coil spring, other spring mechanisms, as known in the art, can be used in conjunction with the present invention, for example a plate spring. Preferably, identical constructions of the connection shown in FIG. 3 are used on each of the members  12 , so that spring mechanisms are in place on both sides of the rotatable handle  22 . This provides the most balanced spring force to assist the user. Alternatively, it is possible for the spring mechanism to only be used on one side of the handle  12 .  
         [0023]    In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and, described without departing from its spirit or scope.