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CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the priority of U.S. Provisional Patent Application No. 61/465,010 filed Mar. 14, 2011. 
     
    
     BACKGROUND 
       [0002]    This disclosure relates generally to implements for shoveling snow and similar materials. More particularly, this disclosure relates to ergonomic implements which are designed to facilitate safe usage and prevent injuries due to physical stress resulting from usage. 
         [0003]    It is a well-established fact that every year, there are numerous injuries—and sometimes even deaths—resulting from the shoveling of snow. For example, the Providence Journal, in a Feb. 1, 2011 article, reported that 12,000 deaths occur each year as a result of heart attacks suffered while shoveling snow. Furthermore, the magnitude of muscular and skeletal injuries incurred due to shoveling snow is enormous. 
         [0004]    Many of the efforts to counter the very dangerous and adverse effects of shoveling snow have centered on enlisting the use of power equipment and/or physically fit shovelers who have a physique more adapted to the exertion and physical requirements for shoveling snow. Such efforts have not successfully addressed the reality that regardless of the warnings and dangers, individuals are, for numerous reasons, prone to ignore the risks and shovel snow. 
       SUMMARY 
       [0005]    Briefly stated, an ergonomic snow removal implement comprises an elongated handle and a blade unit which is mounted to the handle. The blade unit is semi-flexible and has a generally triangular shape. A fulcrum is disposed in an intermediate position of the blade unit. The implement functions so that a load applied to the blade unit causes the blade unit to flex about the fulcrum and resiliently spring back to a non-flex configuration when the load is removed. 
         [0006]    The handle is preferably semi-flexible. In one embodiment, the handle is bamboo. The blade unit comprises a distal plough member and a plurality of tines connecting the plough member. The tines are also attached to the handle. The tines converge in overlapping fashion and form an apex. In one embodiment, the tines are attached to the handle by a band connector. The fulcrum comprises a cross-piece which extends transversely relative to the handle. 
         [0007]    An ergonomic snow removal implement, in one embodiment, comprises an elongated semi-flexible handle defining a longitudinal axis. A blade unit comprises a plurality of tines disposed in a fan-shaped, generally triangular configuration with an apex portion being attached to the handle and a base portion mounting a plough member extending transversely to said longitudinal axis. A fulcrum is disposed at an intermediate location of the blade unit and is attached to the handle. A load applied to the blade unit causes the blade unit to flex about the fulcrum. When the load is removed, the blade unit springs back to the non-flex configuration. 
         [0008]    The fulcrum comprises a cross-piece generally perpendicular to the longitudinal axis of the handle. The handle is formed from bamboo. The plough member, in one embodiment, has a generally trapezoidal shape and, in another embodiment, has a rectangular shape. The plough member is fastened to each of the tines. In one embodiment, the implement employs nine tines, and a second cross-piece is disposed perpendicular to the longitudinal axis of the handle and attaches to the first cross-piece to sandwich the tines between the cross-pieces. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0009]      FIG. 1  is a rear elevational view of an ergonomic snow removal implement with the implement being oriented in an upright position; 
           [0010]      FIG. 2  is a fragmentary rear elevational view of a second embodiment of an ergonomic snow removal implement; 
           [0011]      FIG. 3  is a fragmentary front elevational view of the ergonomic snow removal implement of  FIG. 2 ; 
           [0012]      FIG. 4  is a fragmentary rear elevational view of a third embodiment of an ergonomic snow removal implement; and 
           [0013]      FIG. 5  is a fragmentary front elevational view of the ergonomic snow removal implement of  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    With reference to the drawings wherein like numerals represent like parts throughout the several Figures, an ergonomic snow removal implement is generally designated by the numeral  10  in  FIG. 1 . The implement has an ergonomic design which essentially automatically limits the load and thus provides a safe limit to the level of cardiovascular exertion of the user. In addition, the implement  10  efficiently exploits a designed resilience to facilitate the unloading phase during usage and to thus limit the physical stress exerted on the user. 
         [0015]    The implement  10  comprises an elongated handle  20  which mounts a fan-shaped blade assembly  30 . The handle  20  is preferably formed of wood or other suitable material and is dimensioned to allow the user to assume and maintain a relatively upright posture while using the implement to, for example, remove snow. In one embodiment, the handle  20  is formed from bamboo or other similar semi-flexible, quasi-rigid material. The handle  20  has sufficient integrity to apply leverage for the lifting and unloading phases of the shoveling action while also having a length of sufficient dimension for pushing loads along a surface, if desired. 
         [0016]    The blade assembly  30  comprises a plurality of tines  31 - 39  which converge for joining in overlapping fashion at an apex  40  and outwardly diverge to form a relatively straight base in a configuration which is essentially triangular in shape and specifically preferably in the form an isosceles triangle. In one example, the width of the tines  31 - 39  is uniform and is on the order of 25 mm, although other variations are clearly possible. The length of the tines  31 - 39  is a function of the desired length and base of the blade assembly. In one example, a 42 cm base requires outer tines having approximately the same length from the base to the apex  40 . It will be appreciated that the lengths of the tines  31 - 39  decrease as a function of the proximity to the center longitudinal line. In addition, the number of tines may vary. 
         [0017]    A solid plough board  50  connects the tines  31 - 39  at the base of the configuration and extends from side to side toward the apex  40 . The plough board  50  may have a trapezoidal-type form. In some embodiments ( FIGS. 2-5 ), a rectangular form is employed. The plough board  50  is secured to each of the tines by rivets  52 , threaded fasteners, adhesives, lashings or other fastening means. The plough board  50  functions to provide an anchoring mechanism for the tines  31 - 39  for fixedly securing same as well as to provide a platform that prevents material from falling through the spaces between the tines near the base of the blade assembly. Alternatively, the plough board may comprise a pair of members disposed on opposite sides of the tines in a sandwich-type arrangement. The plough board may be a wood, metal, plastic or other suitable material. 
         [0018]    A pair of cross-pieces  60  and  62  (only cross-piece  60  illustrated in  FIG. 1 ) is located between the apex and the plough board  50  and is dimensioned and positioned to sandwich the tines  31 - 39 . In one embodiment, the cross-pieces are located from the apex a distance which is approximately ⅓ the distance of the blade assembly from the apex to the base of the plough board. Cross-piece  60  is directly connected to the handle  20  by a fastener  22 . Various fasteners  64  may be employed to connect the cross-pieces  60 ,  62  together. In one form, a pair of opposed twisted wires connect the cross-pieces. The cross-pieces function as a fulcrum for the tines, as will be further described below so that when a load is applied to the blade assembly  30 , the blade assembly  30  will resiliently flex about the cross-piece  60 , which is attached to the handle. 
         [0019]    Alternatively, the tines below the cross-piece  60  may be split into two, three, four or more sectors which extend from the cross-piece to the plough board. In this embodiment, the plough board must be glued to the ends of the tines or a pair of plough board members are employed at opposed sides of the ends. In this latter embodiment, the plough board members may be fastened to the ends of the tines by adhesive and the pair of members may be joined to each other at extreme end portions by rivets or other types of fasteners. 
         [0020]    The upper portion of the tines  31 - 39  forms an overlapping array about the apex  40 . A band-type connector  24  encircles the overlapping tines and wraps around the handle for securing the tines to the handle. In one form, lashings, twisted wire or other band clamp or band connector arrangement may be employed. 
         [0021]    The ergonomic snow removal implement  10  is employed so that the plough board  50  and blade assembly  30  engage under the snow to be lifted. As the snow is lifted, the blade assembly flexes slightly about the cross-piece  60 . The flexure force is essentially provided by the interplay of the gravity and the flexure of the tines  31 - 39 . As the implement stops at the far extent of its arc-like travel, the resilient blade assembly returns to a normal flexure state from the deflected flexure state created under the force for which it has been downwardly deflected. The snow springs toward its intended destination with a reduced application of human effort as compared to a fixed, rigid-type snow blade. 
         [0022]    With reference to  FIGS. 2 and 3 , snow removal implement  10 A differs from implement  10  by virtue of the plough board  50 A which is rectangular in shape. Plough board  50 A has generally the same length and width dimensions as plough board  50 . 
         [0023]    With reference to  FIGS. 4 and 5 , implement  10 B is substantially the same as implements  10  and  10 A except for the plough board configuration of plough board  50 B. Plough board  50 B has a narrower strip-like form with a generally rectangular shape. 
         [0024]    It should be appreciated that for some embodiments, the handle may extend beyond the cross-pieces  60  and terminate at an intermediate portion of the blade assembly. Alternatively, if the handle is sufficiently flexible, the handle may extend to connect with the plough board. 
         [0025]    The implements  10 ,  10 A and  10 B also provide a significant biomechanical advantage. The transfer of weight onto the musco-skeletal system of the shallow blade is gradual because the flexure of the blade assembly causes the load to lie in an inert condition until the force applied to it reaches the force required to raise the load. The initial force applied to the implement to flex the tines and the additional force bends the tines further until they are fully deflected in a quantum of force. The handle  20  may also provide a more limited degree of flexure. The application of force is gradual throughout the lifting action. The quantum of force used to ultimately lift the load from the point of full deflection of the tines off of the ground or surface is small in comparison with the change in force required when a rigid platform or blade of similar dimensions serves to lift the load. There is also a smooth gradual transition from rest to full effort instead of a jerking, disruptive, discontinuous-type action when the load is engaged in its entirety and when it is wrenched free from the ground. The beneficial effect of this flexure design on the human body is akin to the reduction of wear and tear on an automobile when acceleration and deceleration are gradual. 
         [0026]    In addition, the fan-like, triangular geometrical shape of the blade assembly  30  essentially provides a smaller area of snow to be lifted than a corresponding rectangular design because of the smaller area for a given effective footprint. Thus, the loads will be naturally reduced. The shoveling of snow becomes a light, aerobic exercise with cardiovascular heart rates well within the target zone for strengthening cardiovascular efficiency. In addition, lighter loads plus a significant alignment reduce or eliminate muscle strains and provide a highly efficient snow removal implement.

Summary:
An ergonomic snow removal implement incorporates a structure which provides an efficient flexure of the implement during the lifting and releasing of the load. In addition, the load carrying portion of the implement is specifically designed to provide a reduced area and consequently, a self limit to the load of each shoveling action.