Abstract:
The trenching shovel is narrow at its digging end so that a lot less dirt is required to be removed. The trenching shovel has a three sided blade and the shovel point has a concave, sharp edge which partially wraps around a root to permit cutting of the root without the blade slipping off. The three sides are also angled slightly outward to help prevent dirt from sticking to the channel of the shovel and to compact the side edges of the trench to prevent collapse of the sidewalls into the formed trench.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of priority of U.S. provisional application No. 62/170,839, filed Jun. 4, 2015, the contents of which are herein incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to shovels and, more particularly, to shovels for digging trenches for burying of items such as cable, wiring, piping and the like under the surface of the ground. 
     Prior to this invention, digging a trench (twelve inches deep) to bury wires or piping usually required the removal of a substantial of extra dirt and cutting through root systems. Narrow bladed shovels in the art are known, however, these shovels still present challenges in their abilities at removing excavated dirt from within the formed trench and do not maintain the sidewalls of the trench. Moreover, these shovels still encounter the same limitations in their ability to cut through subterranean roots. 
     As can be seen, there is a need for a trenching shovel that is narrower so a lot less dirt is removed. Each of the three sides of the shovel point has a concave, sharp edge which partially wraps around a root without slipping off. The three sides are also angled slightly outward to help prevent dirt from sticking to the channel of the shovel. 
     SUMMARY OF THE INVENTION 
     In one aspect of the present invention, a trenching shovel includes an elongated handle operatively attached to a shovel head, the shovel head having a left and a right upturned sidewall extending from an aft sidewall and defining a trenching channel therein. The trenching shovel may also include a depth guide having opposed apertures defined in the left and the right side wall; and a depth guide pin extending through the opposed apertures. The trenching shovel may also include a concave edge surface defined in a ground penetrating edge of the left and right upturned sidewalls. A concave edge surface may also be defined in a ground penetrating edge of the aft sidewall. The concave edge surface may also be a sharpened edge. A foot bar may extend laterally across the shovel head proximal to an attachment end of the shovel head and the foot bar may also be provided with an upturned end portion. 
     In other aspects of the invention, the aft sidewall is outwardly tapered between a ground penetrating tip and an area proximal to a handle attachment end. The lateral sidewalls are configured to taper outwardly along the lateral aspects of the aft sidewall. The aft sidewall of the trenching shovel may also be angled with respect to the handle towards an opening of the trenching channel. 
     In yet other aspects of the invention a trenching shovel has a handle; a shovel head operatively coupled to the handle; and a trenching channel formed in the shovel head, the trenching channel having a ground penetrating end distal from the handle. The trenching channel may be defined wherein a left and a right sidewall taper outwardly from the ground penetrating end to an end proximal to the handle. A concave edge surface can be defined in the ground penetrating end of the trenching channel. The trenching shovel may also have an adjustable depth guide pin operatively received in opposed apertures defined in the left and right sidewalls. A foot bar is operatively attached to the blade head proximal to the handle. 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of a trenching shovel shown in use. 
         FIG. 2  is a top perspective detail view of the trenching shovel head. 
         FIG. 3  is a bottom perspective detail view of the trenching shovel head. 
         FIG. 4  is a side detail view of the trenching shovel head. 
         FIG. 5  is a top view of the trenching shovel head. 
         FIG. 6  is a front view of the trenching shovel. 
         FIG. 7  is an exploded view of the trenching shovel head. 
         FIG. 8  is a detail view of a foot bar. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims. 
     Broadly, an embodiment of the present invention provides a narrow head trenching shovel which provides efficient digging by limiting the removal of dirt to no more than is necessary. The trenching shovel still allows the trench to be wide enough for piping or cables to be buried. 
     As stated above, prior to the present invention, digging a trench (twelve inches deep) to bury wires, cables or piping usually required the removal of a lot of extra dirt and presented the extra difficulty of cutting through root systems. 
     As seen in reference to  FIG. 1  an embodiment of a trenching shovel  10  according to the present invention is illustrated. The trenching shovel  10  has a head  12  disposed at the end of an elongate handle  40 . The head  12  may have at least one foot bar  22  extending laterally from a longitudinal length of the shovel  10 . 
     A user  32  grasps the handle  40  with their hands  42  to work the head  12  into a ground surface  34  to dig a trench  36 . The user  32  may apply their foot  38  to the at least one foot bar  22  to apply additional force to drive the shovel head  12  into the ground surface  34  to dig the soil and form the trench  36 . 
     As seen in the drawings of the trenching shovel head  12  shown in  FIGS. 2-7 , the shovel head  12  is formed by a left and a right upturned sidewalls separated by an aft sidewall to define a trenching channel  15 . The shovel head  12  may be formed from any suitable material, and is preferably selected from a 14 gauge tempered steel. 
     The left and right sidewalls may have a forward curvilinear ground penetrating edge surfaces  14  that extend from an upper corner of the sidewalls to their juncture with the aft sidewall. Likewise, the aft sidewall may also include a forward curvilinear ground penetrating edge surface  16  that extends between the juncture with the left and right sidewalls. The curvilinear surfaces are preferably concave into the lateral aspects of sidewalls to define opposed root securing points. Preferably, the forward edge surfaces  14  &amp;  16  have a sharpened blade edge. 
     The concave surfaces are configured, such that upon engagement of the edges  14  &amp;  16  with the ground neatly slices the sides of the trench, any overlying area of sod, and roots that may be encountered. The edges  14  &amp;  16  contain the root so that the root may be cut by the sharpened blade edge. With the sharpened blade edges  14  in the upturned sidewalls, roots running laterally across the trench  36  may be cut, while leaving the sides of the trench intact. The concave, blade edge design on the three sidewalls ensures a good grip on a root system without the shovel head slipping off. 
     The spacing between the upturned sidewalls may be selected based on a desired width of the trench. In application, the inventor has found that a spacing of about 2½ inches in width provides efficient digging by limiting removal of any more dirt than necessary. It is also allows the resultant trench to be wide enough for small diameter piping or cables to be buried. 
     The sidewalls may have a length of approximately 14 inches. The aft sidewall may have a gradually tapered width beginning at the concave edge  16  and extending outwardly towards a head attachment end  20 . With the left and right sidewalls formed along the tapered edge the channel has a narrowed opening at the ground penetrating end and opens to a widened area proximal to the head attachment  20 . The tapered left and right sidewalls serve to pack the sidewalls of the formed trench outwardly so as to prevent collapsing of the trench sidewalls. The expanded region of the channel proximal to the head end also permits the excavation of a greater volume of dirt with each lift. 
     In forming a trench  36 , it is often desirable that the trench  36  have a uniform, or minimum depth beneath the ground surface  34 . As such, the trenching shovel  10  of the present invention may also include an adjustable depth gauge, which is formed by a depth guide pin  28  extending between opposed apertures  18  defined in the left and right sidewalls. The depth guide pin  28  may be retained within the opposed apertures by any suitable means, such as by a hitch pin  30 . The opposed apertures  18  may be defined in a spaced apart relation along the longitudinal length of the sidewalls. The opposed apertures  18  may be at a fixed spacing, or at a spacing to correspond to minimum burial depths specified by local building codes for buried cables and piping. In a preferred embodiment, three holes are drilled on each of the two sidewalls of the shovel head to hold the depth controlling pin in place at the 4″, 8″ or 12″ positions. 
     As previously indicated, the sidewalls of the shovel head  12  are configured to terminate proximal to the head attachment end  20  of the shovel head  12 . The head attachment end  20  may be formed as a generally cylindrical shape to wrap around the shovel handle  40  or otherwise form a socket to receive the handle  40 . The handle  40  may be formed from any suitable material, such as wood, fiberglass or metal. In a preferred embodiment the handle  40  is on the order of about 3½ feet long. The head may be secured to the handle by any suitable fasteners, such as nuts and bolts, rivets, welds, or adhesives. 
     The foot bar  22  may be attached to the shovel head  12  by any suitable means. As seen in reference to  FIGS. 3 and 4 , the foot bar  22  may be welded to the head attachment  20 . The foot bar  22  may also include upturned ends to assist with retaining the user&#39;s foot  38  on the foot bar  22 . The foot bar  22  may be formed from any suitable material, and is preferably formed from a 1 inch×6 inch piece of angle iron with a half circle portion cut out (refer to  FIG. 8 ) of the angle iron, which radius coincides with the radius of the outside cylindrical head attachment  20 , then welded in proper place. As will be appreciated, the angle iron foot-bar  22  could be eliminated if the shovel head  12  could be forged to include the shaping of the foot-bar  22  in one piece construction. 
     In use, the user  32  could mark on the ground with spray paint, etc. where the trench  36  will be dug. The user  32  would start by digging a small starter hole and then simply follow the marked line. To utilize the tapered sidewall configuration to its best advantage, the user  32  should dig by facing the starting hole and thrust their foot  38  down on the foot-bar  22 , digging a longitudinal length of about three inches of dirt at a time. If ground conditions permit a depth of 12-14 inches in depth may be dug if desires at each scoop. The user  32  would continue digging as needed to obtain a trench  36  of the desired length and utilizing the depth guide pins  18 , to the desired depth. 
     It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.