Abstract:
The invention relates to a shovel particularly useful for snow removal. The shovel is characterized by dual ground contacting edges allowing the shovel to be self-supporting and which allows the shovel to be used in an ergonomically efficient manner for removing snow from a surface.

Description:
FIELD OF THE INVENTION 
     The invention relates to a shovel particularly useful for snow removal. The shovel is characterized by dual ground contacting edges allowing the shovel to be self-supporting and which allows the shovel to be used in an ergonomically efficient manner for removing snow from a surface. 
     BACKGROUND OF THE INVENTION 
     Snow removal shovels are well known. Various types of shovels have been used and developed over the years for particular uses or applications. For example, shovels having specialized handles and blades have been developed for lifting snow whereas other shovels have specifically been developed for pushing or plowing snow. In other shovels, particular aspects of the handles or blades have been designed in an attempt to improve the ergonomics and/or efficiencies of using the shovel. 
     While particular shovels have been designed with improved ergonomics and/or efficiencies of use, for particular applications, such as the clearing of walkways or driveways, shovels have not always enabled ergonomically efficient methodologies for the clearing of snow from a surface. In particular, past shovels have required either the lifting of a snow-laden shovel from the surface and carrying or throwing the snow away or pushing the snow in a manner that is ergonomically inefficient. These inefficiencies are particularly relevant to physically weaker persons, such as the elderly, who as a result of these inefficiencies may cause harm to themselves through the use of a shovel thereby giving themselves back problems, muscle strains or increasing the risk of heart attack through over-exertion. Such risks of harm may cause these people to be hesitant to make the effort to clear snow from their driveways or walkways which may lead to dangerous accumulations of snow and the resulting risk of slip and fall injuries. 
     Furthermore, past shovels are not self-supporting during non-use. That is, in order for a user to retrieve a shovel for use that is lying flat on the ground requires the user to bend over to lift the shovel or, alternatively retrieve the shovel from against a wall that the shovel may have been leaned against. Similarly, after use, past shovels must be returned to a supporting wall and carefully balanced against the wall or allowed to drop to the ground. Leaning shovels against a wall is often unstable with the result that the shovel may slip causing other shovels or similarly positioned implements to crash to the floor of a garage, shed or storage room. This is not only inconvenient but may also result in damage to cars or other stored equipment. 
     Still further, in snowy regions, shovels are often jammed into a snowbank by a user in order to support the shovel during or after use. Very often, the shovel will fall over and become lost beneath new snow as it falls thereby increasing the risk of damage by a vehicle running it over or simply inconveniencing a user by it not being available when needed. 
     Accordingly, there has been a need for a shovel which allows for the pushing of snow in an ergonomically efficient manner and which is self-supporting. 
     Examples of past shovels which provide various operational features are described. For example, U.S. Pat. No. 6,053,548 discloses a manually operable combination shovel and plow; U.S. Pat. No. 5,829,808 discloses an adjustable angle snow plow; U.S. Pat. No. 2,919,153 discloses a combination snow shovel and plow tool; U.S. Pat. No. 4,199,181 discloses a snow shovel having a diagonal curve; U.S. Pat. No. 2,896,993 discloses a snow shovel having an adjustable blade; U.S. Pat. No. 5,159,769 discloses a combination snow shovel and plow; U.S. Pat. No. 5,159,769 discloses a shovel having shovel and plow characteristics and; U.S. Pat. No. 5,511,328 discloses a snow plow having adjustable blades. In particular, none of the devices described in these patents is self-supporting. 
     SUMMARY OF THE INVENTION 
     In accordance with the invention, there is provided a shovel comprising: 
     a blade having first and second ground contacting edges; 
     a handle operatively connected to the blade 
     wherein the handle and blade allow pushing operation of the shovel with either of the first or second ground contacting edges in contact with the ground. 
     In a more specific embodiment, the invention provides a self-supporting shovel comprising: 
     a blade having first and second ground contacting edges and any one of or a combination of a semi-circular, semi-elliptical -or parabolic cross-section; 
     a handle operatively connected to and angled with respect to the blade 
     wherein the handle and blade allow pushing operation of the shovel with either of the first or second ground contacting edges in contact with the ground. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     These and other features of the invention are described with reference to the drawings wherein; 
     FIG. 1 is an isometric view of the shovel in accordance with one embodiment of the invention; 
     FIG. 2 is a plan view of the shovel in accordance with one embodiment of the invention; 
     FIG. 3 is a side view of the shovel in accordance with one embodiment of the invention; 
     FIG. 3 a  is a partial side view of one blade of the shovel having reinforcement; 
     FIG. 4 is a perspective view of a shovel in accordance with one embodiment of the invention in a stored and upright position; 
     FIG. 5 is a side view of a shovel in accordance with one embodiment of the invention wherein the radius of curvature of the blade is different across the width of the blade; 
     FIG. 6 is a side view of an alternate embodiment of the handle in accordance with one embodiment of the invention; 
     FIG. 7 is a plan view of a shovel in accordance with one embodiment of the invention wherein the position of the handle is variable with respect to the blade. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to the Figures, a shovel  10  having a blade  12  and handle  14  is described. The shovel  10  is particularly adapted for pushing material such as snow in a manner similar to that of a snowplow. While the shovel is particularly adapted for pushing snow, it is understood that other materials may be pushed by the shovel and, accordingly, reference to snow is not meant to be limiting to the scope of interpretation of the uses of the shovel. 
     The blade  12  of the shovel  10  is generally semi-cylindrical as shown in FIGS. 1,  3  and  4  with the blade  12  having first and second ground contacting edges  16  and  18 . In other embodiments, the blade  12  may be semi-elliptical or parabolic in cross-section. As shown, it is preferred that the handle projects outwardly from the convex surface of the blade  12  midway between the first and second ground contacting edges  16  and  18  and midway between a leading end  20  and trailing end  22  of the blade  12 . As shown in FIG. 2, it is also preferred that the handle is angled with respect to the blade  12  as denoted by θ. 
     The shovel  10  is particularly adapted to clear snow on surfaces such as driveways and walkways. In normal operation, the user would initiate the snow clearing routine at one edge or in the middle of the driveway or walkway. By engaging the first ground contacting edge  16  against the driveway or walkway and by pushing the handle in a desired direction x (normally parallel to one edge of the driveway or walkway), snow is collected by the blade and ejected from the blade at trailing end  22  in a direction y. The ejection of the snow is a result of the angle θ between the blade and the handle and the forward motion of the shovel  10 . More specifically, as snow encounters the inner concave surface of the blade  12 , it rises up the inner surface of the blade  12  to a position at which gravity causes the rising snow to fall and be deflected towards the trailing end  22  at which position it exits the shovel  10 . The ejected snow results in a berm  24  of snow generally parallel to the direction of travel x and the area of the driveway or walkway beneath the blade has been cleared of snow. The handle would typically be held by the user at an angle of approximately 30-60 degrees with respect to the horizontal as shown in FIG.  3 . 
     The user, upon reaching the end of the driveway or walkway would reverse the direction of travel and by rotating the blade of the shovel in a direction z (FIG. 3) would place the second ground contacting edge  18  against the driveway or walkway. With both ground contacting edge  16  and ground contacting edge  18  on the driveway/walkway surface  26 , the shovel  10  would be in a self-supporting position. By stepping over or around the shovel  10 , the handle  14  would be continued to be rotated in the direction z in order to lift the first ground contacting edge  16  from the surface  26 . Thereafter, and by orienting the handle in order that it is parallel to the berm  24  and the leading end  20  is adjacent and aligned with the berm  24 , the user pushes the shovel in a direction parallel to the berm  24  so as to continue the ejection of snow from the trailing end  22 . By successively repeating passes as described above, the user can effectively cause the movement of snow from the driveway or walkway to a location lateral to the driveway or walkway without lifting the shovel  10  from the surface. It is understood that the actual use of the shovel will depend on snow conditions with the specific actions of the user being modified to the specific conditions. 
     During non-use or storage, the shovel is self-supporting when placed on its first and second ground contacting edges  16 ,  18  as shown in FIG.  4 . 
     In order to maximize the efficiency of the use of the shovel  10 , the first and second ground contacting edges  16 ,  18  of the blade  12  are provided with a bevelled edge  30 ,  30 ′ to promote the blade&#39;s snow lifting or scraping action close to the ground. That is, by providing a bevel, the edge of the shovel  10  is made sharper in order to promote dislodging compacted snow or ice from the ground. The angle of bevel, γ, is preferably in the order of 45 degrees in order to correspond to the average angle of the handle  14  with respect to the horizontal during use. 
     In another embodiment, the first and second ground contacting surfaces are provided with a reinforced edge  32  of metal or plastic to provide a sharper or reinforced edge as shown in FIG. 3 a.    
     Further still, it is preferred that the blade  12  is provided with rounded corners  40  at the leading corner of both the first and second ground contacting surfaces to facilitate the shovel&#39;s ability to ride over imperfections in the ground which might otherwise cause the blade  12  to catch on the ground. 
     Still further, it is also preferred that the leading end  20  and trailing end  22  are parallel to the handle  14  to enable the blade to be placed tightly against a vertical surface at the edge of a driveway or walkway. 
     In another embodiment, the blade is provided with a different or varying radius of curvature between the leading end  20  and trailing end  22  of the blade  10  as shown in FIG.  5 . The radius of curvature of either a fixed or variable curvature blade will typically be in the range of 4-12 inches although these dimensions are not intended to be limiting. 
     In a still further embodiment of the blade, the leading edge of the blade  20  may be provided with a cap  55  to minimize spillage of snow from the leading edge during use as shown in FIG.  7 . 
     The handle  14  of the shovel  10  may have various embodiments including a straight or a bent shaft. Specific embodiments of the handle  14  may include an auxiliary handle  50  or handles to promote the ergonomics of using the shovel  10 . In particular, an auxiliary handle as shown in FIG. 6 may be provided wherein the auxiliary handle  50  may rotate about the main handle  14 . Other embodiments may provide one or more auxiliary handles in a fixed position. 
     In one embodiment as shown in FIG. 7, the angle of the blade  12  with respect to the handle  14  is adjustable (FIG. 7) enabling the user to set a particular angle for optimization of the use of the shovel depending upon the depth and characteristics of the snow. That is, in the event that the snow is deeper and/or heavier, the user may select a smaller angle θ, so as to effectively reduce the width of the blade  12  as it is pushed through the snow. 
     In another embodiment, the handle may be selectively offset with respect to the blade  14  by moving the handle along a track  60  on the blade  12  as shown in FIG.  7 . 
     The shovel  10  may be manufactured from materials known to those skilled in the art including various woods, metals and plastics.