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FIELD OF THE INVENTION 
   The present invention relates to the field of two-handled shovels. More specifically, the present invention relates to snow shovels having rotatable hand grips. 
   BACKGROUND 
   The concept of two-handled shovels is not new. Many instances of two-handled shovels exist in the prior art. Some examples include accessory handles that attach to the shaft of a conventional shovel whereas other examples may comprise a second handle or shaft or a flexible cord attached to the juncture of the shovel blade and the shaft allowing the shovel to be used with both hands. The second handle provides the ability to apply extra leverage and force to the shovel in lifting and/or moving the load carried by the shovel. The second handle also permits a person to lift or move a heavier load without having to stoop or bend over and grasp the shovel handle near the blade. In moving snow, for example, the snow may be laden with moisture and be very heavy to move. Moving snow under these conditions can be very strenuous and hard on a person&#39;s arms and back. 
   As two-handled shovels are supported by both hands, each handle of the shovel moves along separate paths or arcs as determined by the length of a person&#39;s arms. If each handle is gripped tightly in order to move a heavy load with the shovel blade, each hand must turn, at the wrist, in the direction in the shovel is being moved. One hand will turn inward at the wrist whereas the other will turn outward at the  wrist. This may cause pain and discomfort if the shovel is being used to move heavy or multiple loads. 
   It is, therefore, desirable to have a two-handled shovel where the hands do not need to bend or turn at the wrists when lifting or moving a load with a shovel. 
   SUMMARY 
   The present invention is concerned with a two-handled snow shovel having rotatable hand grips at each handle. The shovel comprises a shaft with a D-shaped handle with a rotating grip located at the upper end of the shaft. The grip rotates about a rod that extends between the sides of the handle. The lower end of the shaft is inserted into a shaft insert sleeve attached to the rear side of the blade. Mounted near the top of the blade on the rear side is a second handle assembly capable of pivoting forwards and backwards. 
   In one embodiment of the present invention, the second handle assembly is an inverted U-shaped rod having two legs and a handle portion. The lower end of the assembly is pivotally attached to a pivot bracket mounted on the rear side of the blade between the top edge of the blade and the shaft insert sleeve. The upper end of the second handle assembly comprises a second hand grip also capable of rotating. In an alternate embodiment, the blade is made from injection molded plastic and the pivot bracket is molded as part of the blade itself. 
   In another embodiment of the present invention, each leg of the second handle assembly is capable of adjusting in length. Each leg is comprised of an upper and lower leg member. The upper leg members and the handle portion are formed from a single piece of solid rod. A rotatable hand grip, such as a piece of thick-walled tube  or sleeve, is slipped over the rod before the rod is bent into an inverted U-shaped piece. At the lower end of each upper leg member is a long nut welded to the rod wherein the axis of the nut opening is parallel to the axis of the rod. Each lower leg is a piece of threaded rod that threads into the long nut. The overall length of each leg is then determined by the amount each lower leg is threaded into the long nut. The lower end of each lower leg is bent into an L-shape and placed through apertures in the pivot bracket. Nuts are then threaded on to the end of each lower leg to retain the lower leg to the bracket and permits the second handle assembly to pivot about the pivot bracket connection. 
   In another embodiment of the present invention, both the upper and lower leg members are made from threaded rod. The upper leg member and handle portion would be made from rod having right-handed threads whereas the lower legs would be made from rod having left-handed threads. The converse could be true as well. To connect the upper legs to the lower legs, a sleeve having internal right-handed threads at one end and internal left-handed threads at the other end are used to couple the upper and lower legs together on each side of the second handle assembly by threading the upper and lower legs into the sleeve. Similar to a turnbuckle, turning the sleeve clockwise or counterclockwise will either shorten or lengthen the overall length of each leg of the second handle assembly. 
   In another embodiment, both the upper and lower legs are made from threaded rod having right-handed threads. Two long nuts are welded together to form a coupling nut that fastens the upper and lower legs together. The upper leg threads into one of the long nuts of the coupling nut from one end whereas the lower legs threads into the other long nut from the opposite end.  
   Broadly stated, the present invention is a shovel comprising a shaft having upper and lower ends defining a longitudinal axis, a shovel blade having top and bottom edges, a concave front side and a convex rear side, the rear side having a shaft insert sleeve for receiving the lower end of the shaft, the rear side further having a pivot bracket mounted between the top edge and the shaft insert sleeve, the pivot bracket having opposing left and right apertures that define a pivot axis, the pivot axis substantially perpendicular to the shaft and substantially parallel to the top edge of the shovel blade, a first handle at the upper end of the shaft defining a first axis, the first handle having a first grip, the first grip capable of rotating about the first axis, and a second handle assembly comprising substantially parallel left and right leg portions and a handle portion, each leg portion having upper and lower ends, the upper ends of the leg portions defining a second axis, the hand portion positioned between the upper ends of the leg portions, the lower end of the left leg portion pivotally attached to the left aperture and the lower end of the right leg portion pivotally attached to the right aperture, and a second grip pivotally attached to the handle portion, the second grip capable of rotating about the second axis, the second handle assembly capable of pivoting about the pivot axis. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is perspective view of the present invention. 
       FIG. 2  is a side elevational view of the present invention. 
       FIG. 3  is an exploded perspective view of the second handle assembly of the present invention.  
       FIG. 4  is close-up exploded view of the pivoting bracket of the present invention. 
       FIG. 5  is close-up view of the left leg of the second handle assembly of the present invention. 
       FIG. 6  is cutaway view of the first handle of the present invention. 
       FIG. 7  is a cutaway view of the second handle of the present invention. 
       FIG. 8  is a perspective view of an alternate blade of the present invention. 
       FIG. 9  is an exploded perspective view of a first alternate embodiment of the second handle assembly of the present invention. 
       FIG. 10  is a close-up view of the left leg of the first alternate embodiment of the second handle assembly of the present invention. 
       FIG. 11  is an exploded perspective view of a second alternate embodiment of the second handle assembly of the present invention. 
       FIG. 12  is a close-up view of the left leg of the second alternate embodiment of the second handle assembly of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The present invention is concerned with a two-handled shovel having rotatable hand grips at each handle. As shown in  FIGS. 1 and 2 , shovel  10  comprises a blade  12  having a concave front surface  13  and a convex rear surface  15 . On rear surface  15  is shaft insert sleeve  14  which receives the lower end of shaft  16 . Handle  18  is mounted on the upper end of shaft  16 . Handle  18  is preferably a D-shaped handle and has rotatable hand grip  20 . Mounted on blade  12  is U-shaped pivot bracket  32 . Attached to pivot bracket  32  is second handle assembly  19 . Second handle assembly   19  comprises of upper leg members  22 A and B, lower leg members  24 A and B and hand grip  30 . 
   In the preferred embodiment, as shown in  FIGS. 3 and 4 , pivot bracket  32  is bolted to blade  12  by bolts  38 A and B passing through apertures  42 A and B of backing plate  36 , through corresponding apertures in blade  12 , through apertures  44 A and B of pivot bracket  32  and secured by nuts  40 A and B. Lower legs  24 A and B are made of threaded rod whose lower ends are bent 90 degrees into ends  25 A and B. Preferably, lower legs  24 A and B are made from ¼″ or {fraction (5/16)}″ diameter threaded rod and upper legs  22 A and B are made from ¼″ or {fraction (5/16)}″ diameter solid rod. Ends  25 A and B pass through apertures  34 A and B of bracket  32  and are secured with nuts  28 A and B. Preferably, nuts  28 A and B are aircraft-style or self locking nuts. In an alternate preferred embodiment, where blade  12  is preferably made of injection-molded plastic as shown in  FIG. 8 , bracket  32  is formed by bracket ears  46 A and B having apertures  34 A and B being molded as part of blade  12 . 
   The preferred embodiment of the present invention permits the overall length of second handle assembly  19  to be adjusted. As shown in  FIG. 5 , the lower end of upper leg  22  has long nut  26  attached to it, preferably welded. The axis of nut  26  is parallel to the axis of upper leg  22 . Lower leg  24  is threaded into nut  26 . The overall length of second handle assembly  19  is governed by the amount of lower leg  24  is threaded into nut  26 . 
   Shown in  FIG. 6  is a cutaway view of first handle  18 . First grip  20  is a cylindrical tube made of suitable material for gripping that rotates about rod  21  that traverses across the mouth of handle  18 . As shown in  FIG. 7 , the preferred embodiment of second handle assembly  19  has the handle portion and both upper legs   22 A and B formed from a single piece of rod  31 . Second grip  30  is a cylindrical tube made up of material suitable for gripping. Second grip  30  is slid onto rod  31  prior to rod  31  being bent with 90° corners  23 A and B thereby containing grip  30  onto second handle assembly  19 . Second grip  30  is free to rotate on rod  31 . 
   In an alternate preferred embodiment, as shown in  FIGS. 9 and 10 , upper legs  22 A and B are formed from a piece of right-hand threaded rod, and lower legs  24 A and B are formed from left-hand threaded rod, both upper and lower legs are preferably made from ¼″ or {fraction (5/16)}″ diameter threaded rod. Alternatively, upper legs  22 A and B can have left-hand threads and lower legs  24 A and B can have right-hand threads. Sleeves  48 A and B are then used to couple the upper and lower legs together. Sleeves  48 A and B have internal right-hand threads at one end and internal left-hand threads at the other end. Upper legs  22 A and B and lower legs  24 A and B are then threaded into the appropriate end of sleeves  48 A and B. Operating similar to that of a turnbuckle, the length of the legs of second handle assembly  19  is adjusted by turning sleeves  48 A and B clockwise or counter-clockwise. 
   In another preferred embodiment, as shown in  FIGS. 11 and 12 , upper legs  22 A and B and lower legs  24 A and B are made from threaded rod having right handed threads, preferably ¼ or {fraction (5/16)} in diameter. Coupling nuts  50 A and B are used to join the upper and lower leg members together and to permit adjustment of the overall length of the second handle assembly  19 . Coupling nut  50  consists of two long nuts  26  welded together side by side. Upper leg  22  threads into one nut of coupler nut  50  from one end while lower leg  24  threads into the other nut of coupler nut  50  from the opposite end. The overall length of each leg of second handle assembly  19  is  determined by the amount upper leg  22  and lower leg  24  are threaded into coupler nut  50  prior to attaching end  25  to aperture  34  of bracket  32 . 
   In operation, a person grabs grips  20  and  30  of shovel  10  with their hands. As shovel  10  is swung back or pushed forwards, grips  20  and  30  rotate on rods  21  and  31 , respectively. This permits the person to keep their wrists stationary or in a locked position as shovel  10  is used to lift or move a load thereby reducing undue stress or strain on the wrists. 
   While the preferred embodiment comprises a second handle assembly with two parallel legs, it is anticipated that the second handle assembly may consist of a single leg with its lower end pivotally attached to the shovel blade and its upper end comprising a rotatable hand grip. In addition, while the present invention has an application in use with snow shovels, it is anticipated that the present invention may have application in other forms of shovels and other tools used in the lifting and moving of materials such as hay, grain, soil, or coal, as examples. 
   Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention. The terms and expressions used in the preceding specification have been used herein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized at the scope of the invention as defined and limited only by the claims that follow.

Summary:
The present invention is concerned with a two-handled shovel for use in lifting or moving heavy loads, such as snow. The present invention comprises a snow shovel having a second handle assembly pivotally attached to the blade of the shovel. The assembly is an inverted U-shaped element having two legs and a handle grip. Each handle of the shovel has a rotatable hand grip that allows a person to keep their wrists stationary when lifting or moving snow. The second handle assembly further comprises a mechanism for adjusting the length of the legs to suit the person using the shovel.