Patent Publication Number: US-7712805-B2

Title: Sifting shovel

Description:
FIELD OF THE INVENTION 
   The present invention relates generally to tools. More particularly, disclosed herein is a sifting shovel for enabling the separation of dust, ash, and the like from unburned embers to permit, for example, the removal of the dust and ash from a furnace, stove, or the like while enabling the return of the unburned embers for the full and efficient consumption thereof. 
   BACKGROUND OF THE INVENTION 
   Fireplaces and stoves have been employed as sources of residential and even commercial heating for centuries, and their popularity can be seen to increase in relative proportion to increases in energy prices. It will be appreciated that it is economically advantageous to get the most energy possible from wood, coal, heating pellets, and other forms of burnable fuel. It would be ideal, therefore, to ensure that the burnable fuel is as fully consumed as possible and, conversely, that as little unburned fuel as possible is removed from the fireplace or stove during cleaning and the like. One knowledgeable in the art will also be aware that removing as little unburned fuel as possible is desirable to minimize the volume of waste with which a party must contend. 
   A number of prior art inventors, such as Brooks in U.S. Pat. No. 71,969, Cipriano in U.S. Pat. No. 1,675,092, Fisher in U.S. Pat. No. 2,005,416, Neugent in U.S. Pat. No. 4,305,376 to Neugent, and Dixon in U.S. Pat. No. 6,658,285, have sought to provide hand tools for enabling the easy, efficient, and safe sifting of materials. To date, however, the proposed solutions of the prior art have been comparatively limited in effectiveness and complex in structure and operation. 
   For example, many devices of the prior art have disadvantageously removed significant amounts of large coals, embers, and other uncombusted materials from the combustion area thereby leading to unnecessary energy losses. The effectiveness of other prior art constructions has been inhibited by components that inadequately secure heated embers during the removal and transfer of ash from the combustion area to a waste container thereby representing not only a significant fire hazard but also a messy and inefficient arrangement. Still further, certain prior art devices employ moving parts whose function is impaired by individual and repeated heating effects, including thermal expansion and contraction, thereby leading to malfunctioning and premature failure. 
   In light of the foregoing, it will be appreciated that there is a need in the art for a sifting tool for enabling the safe and efficient sifting of unburned embers from dust, ash, and the like to permit, for example, the removal of the dust and ash from a furnace, stove, or the like while enabling the return of unburned embers to the combustion area for permitting the full and efficient consumption thereof with minimal waste. 
   SUMMARY OF THE INVENTION 
   With an appreciation for the state of the art summarized above, the present invention was founded on the basic object of providing an apparatus for safely and efficiently sifting dust and ash and other relative small particles from larger particles, such as incompletely burned embers. 
   A further object of the invention is to provide a sifting shovel capable of efficiently delivering ash to a waste receptacle while limiting the scattering of dust or ash. 
   A further object of the invention is to provide a sifting shovel that enables a sifting of particulate matter from incompletely burned embers while inside a combustion chamber of a fireplace, stove, or the like. 
   A more particular object of embodiments of the invention is to provide sifting shovel of static construction and operation to enable particulate matter to be sifted without impedance that might otherwise derive from thermal deformations of components of the sifting shovel. 
   A further object of embodiments of the invention is to enable uncombusted coal, wood, fuel pellets, and other solid fuel remnants to remain within a combustion chamber for full combustion thereof. 
   A related object of embodiments of the invention is to provide a sifting shovel that minimizes the waste that is yielded during cleaning of a combustion chamber. 
   A further object of embodiments of the invention is to provide a sifting shovel capable of automatically rolling from a shoveling disposition to a discharge disposition to enable a discharge of ash and other retained particulate matter from the shovel. 
   These and in all likelihood further objects and advantages of the present invention will become obvious not only to one who reviews the present specification and drawings but also to those who have an opportunity to experience an embodiment of the sifting shovel disclosed herein. However, it will be appreciated that, although the accomplishment of each of the foregoing objects in a single embodiment of the invention may be possible and indeed preferred, not all embodiments will seek or need to accomplish each and every potential advantage and function. Nonetheless, all such embodiments should be considered within the scope of the present invention. 
   In carrying forth the foregoing objects, a basic embodiment of the present invention comprises a sifting shovel for sifting particulate matter from a volume of material. The sifting shovel has a shovel head and a handle with a proximal end fixed to the shovel head. The shovel head can have a base plate, a sifting plate disposed in spaced relation relative to the base plate, a first side wall, a second side wall, and a proximal end wall. The sifting plate can have a plurality of apertures therein, and the base plate, the first and second side walls, and the rear wall can together define a reception volume for retaining a volume of material. Additionally, the base plate, the sifting plate, and the first and second side walls can have distal ends that together define an open mouth of the shovel head. Under such an arrangement, the shovel head can be inserted into a volume of material, material smaller than a given size can be sifted through the apertures and into the reception volume, and material greater than a given size can be prevented from being sifted through the apertures. 
   The apertures in the sifting plate can be considered to have a maximum aperture dimension, and the open mouth of the sifting shovel can be considered to have a minimum opening height. The minimum opening height can be calibrated to be greater than the maximum aperture dimension, such as by ⅛ inches or more, whereby it can be ensured that material received through the apertures can be emitted through the open mouth. The minimum opening height can be substantially consistent, and the apertures can also be substantially consistent in size and shape. The apertures can pursue any particular shape or combination thereof including, for example, a diamond shape. 
   In certain constructions, the shovel head can have a height that increases from a distal tip to a proximal end thereof such that the shovel head has a truncated wedge shape. While the pitch of the height change can vary, one embodiment of the sifting shovel can have a shovel head that increases at a pitch of approximately 4.5 degrees. The first and second side walls and the rear wall can be disposed substantially perpendicularly to the base plate and can meet the base plate at inside angles that are radiused to prevent the accumulation of debris. Still further, the base plate can have a beveled tip. The sifting plate can be fixed in relation to the base plate thereby to eliminate any moving parts and the potentially deleterious effects that heat can have thereon. 
   The sifting shovel can be considered to have a longitudinal center of gravity, and at least a portion of the handle can be disposed below the longitudinal center of gravity when the sifting shovel is disposed with the sifting plate disposed facing upwardly. The handle can be rounded. With this, the portion of the handle disposed below the longitudinal center of gravity can be rested on an outside surface, such as an edge of a refuse container, and the sifting shovel will tend to turn over automatically to dispense any material retained therein. In one embodiment, this can be accomplished by having at least a portion of the handle angled to a sifting plate side of the shovel head, such as by having a bend adjacent to the proximal end thereof. 
   One will appreciate that the foregoing discussion broadly outlines the more important goals and features of the invention to enable a better understanding of the detailed description that follows and to instill a better appreciation of the inventor&#39;s contribution to the art. Before any particular embodiment or aspect thereof is explained in detail, it must be made clear that the following details of construction and illustrations of inventive concepts are mere examples of the many possible manifestations of the invention. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
     In the accompanying drawings: 
       FIG. 1  is a perspective view of a sifting shovel pursuant to the invention disclosed herein; 
       FIG. 2  is a view in side elevation of the sifting shovel of  FIG. 1 ; 
       FIG. 3  is a perspective view of an alternative embodiment of the sifting shovel of the present invention; and 
       FIG. 4  is a view in side elevation of the sifting shovel of  FIG. 3 . 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   The sifting shovel disclosed herein is subject to a wide variety of embodiments. However, to ensure that one skilled in the art will be able to understand and practice the present invention, certain preferred embodiments of the broader invention revealed herein are described below and shown in the accompanying drawings and figures. 
   Before any particular embodiment of the invention is explained in detail, it must be made clear that the following details of construction and illustrations of inventive concepts are mere examples of the many possible manifestations of the invention. While furnaces, stoves, and the like are commonly referenced herein as the structures from which matter is to be removed, it is to be understood that the sifting shovel could be employed relative to numerous other structures and in widely varied applications. 
   Turning more particularly to the drawings, one embodiment of a sifting shovel pursuant to the present invention is indicated generally at  10  in  FIGS. 1 and 2 . There, the sifting shovel  10  is founded on a shovel head  12 . The shovel head  12  has a base plate  18  retained in spaced relation relative to a sifting plate  16  by first and second side walls  20  and  22  and a rear wall  24 . Together, the base plate  18  and the first and second side walls  20  and  22  define a reception volume for receiving a volume of material. A proximal end of an elongate handle  14  is fixed to the rear wall  24  of the shovel head  12  to enable control and manipulation sifting shovel  10 . The handle  14 , which can be a round tube or rod, can be fixed to the shovel head  12  by any effective method, including welding, a threaded connection, mechanical fasteners, a friction fit, integral formation, or any other suitable method. A hook portion  32  can be disposed at a distal end of the handle  14  for enabling manipulation, handling, and storage of the sifting shovel  10 . 
   The shovel head  12  has an open mouth  28  defined by the distal edges of the base plate  18 , the first and second side walls  20  and  22 , and the sifting plate  16 . The open mouth  28  can be considered to have a minimum opening height H. The height H can be substantially consistent. The shovel head  12  can increase in height from the open mouth  28  to the rear wall  24  thereby to cause the shovel head  12  to pursue a truncated wedge shape. 
   The first and second side walls  20  and  22 , the base plate  18 , and the sifting plate  16  could comprise separate members coupled in any effective manner, such as by welding, fasteners, or any other suitable method. Alternatively, some or all of the first and second side walls  20  and  22 , the base plate  18 , and even the sifting plate  16  could be formed integrally, such as from a single panel of material. The first and second side walls  20  and  22  and the rear wall  24  can be disposed at substantially right angles relative to the base plate  18  whereby the sifting shovel  10  can be readily employed for clearing debris from corners in a fireplace, stove, or the like. Also, the inside angles where the first and second side walls  20  and  22  and the rear wall  24  meet the base plate  18  can be radiused, such as to a ¼ inch radius, thereby to prevent the buildup of material within the reception volume. Still further, the base plate  16  can have a beveled tip  25  for enabling a most efficient shoveling of material. 
   In any case, the first and second side walls  20  and  22 , the base plate  18 , the sifting plate  16 , and the handle  14  could be formed from any suitable material. Of course, based on the likely exposure of the sifting shovel  10  to extremely hot temperatures, the first and second side walls  20  and  22 , the base plate  18 , the sifting plate  16 , and the handle  14  will preferably be formed from a heat resistant material, such as stainless steel. 
   The sifting plate  16  has a plurality of apertures  26  therein for enabling the passage of material through the sifting plate  16  and into the reception volume defined by the first and second side walls  20  and  22  and the base plate  18 . The apertures  26  can be of substantially any shape and can vary in size, and the apertures  26  can be substantially the same or differently sized and shaped. In the depicted embodiment, the apertures  26  are diamond shaped and are substantially identical in shape and disposition over the sifting plate  16 . 
   The apertures  26  can have a maximum aperture dimension A. The minimum opening height H can be calibrated to be a given amount greater than the maximum aperture dimension A. In one example, the minimum opening height H could be ⅜ inches while the maximum aperture dimension A could be ¼ inch such that the minimum opening height H would be ⅛ inches larger than the maximum aperture dimension A. The shovel head  12  can have a maximum height at the rear wall  24  of, for example, 1 inch, a length of approximately 5 inches, and a width of approximately 4 inches. The handle  14  can in certain examples of the invention have a length of, for example, 30 inches. While the invention is not so limited, it has been found to be advantageous to have the shovel head  12  increase in height at a pitch of roughly 4.5 degrees. 
   Under such an arrangement, a user can insert the wedge-shaped shovel head  12  of the sifting shovel  10  into a volume of material to be sifted, such as a mixture of dust, ash, and incompletely combusted embers. Dust, ash, and particles smaller than the open mouth  28  and the apertures  26  can pass respectively therethrough to be received into the reception volume defined by the base plate  16 , the side walls  20  and  22 , and the rear wall  24 . Where the material is shoveled onto the sifting plate  18 , embers larger than the apertures  26  will be prevented from entering the reception volume such that they will remain atop the sifting plate. Those embers can thus be safely and effectively returned to the combustion area by shaking or tilting the shovel head  12 . 
   With this, one can effectively remove dust and ash from a fireplace, stove, or the like while avoiding the removal of incompletely burned materials and the waste and disposal issues associated therewith. By having the minimum opening height H of the open mouth  28  be greater than the maximum aperture dimension A of the apertures  26 , one can ensure that particulate matter that is received through the apertures  26  can be dispensed through the open mouth  28 . With this, buildup of debris within the reception volume is advantageously avoided. 
   As one can perceive from  FIGS. 1 and 2 , at least a portion of the handle  14  can be disposed at an angle in relation to the shovel head  12 . More particularly, the handle  14  can be angled to the sifting plate  18  side of the shovel head  12 , such as by having a bend  30  at a proximal portion of the handle  14 . Such a disposition of the handle  14  in relation to the shovel head  12  allows the sifting shovel  10  to be manipulated most effectively. Additionally, with such a bend  30  along the handle  14 , at least the outside of the bend  30  will be disposed eccentrically to the longitudinal center of gravity of the sifting shovel  10 . 
   It has been found that, when the end  30  or a portion of the handle  14  adjacent thereto is disposed on an external structure, such as on the lip of a refuse container, with the sifting shovel  10  in an upright condition, namely with the sifting plate  18  facing upwardly, the sifting shovel  10  will automatically flip over thereby to cause the material retained in the reception volume to be dispensed. An angle Δ of approximately 11 and ½ degrees has been determined to be effective for accomplishing an automatic flipping of the sifting shovel  10  while not prejudicing the operation thereof. 
   Of course, means aside from a bend  30  for establishing a pivot surface eccentric to the longitudinal axis of the sifting shovel  10  would be readily obvious after reading this disclosure. For example, an automatic rotation of the sifting shovel  10  can be facilitated as is also shown in relation to the sifting shovel  10  of  FIGS. 1 and 2  by having the handle  14  coupled to the rear wall  24  of the shovel head  12  below the longitudinal center of gravity of the shovel head  12 . With this, even where the handle  14  is essentially straight and in line with the longitudinal axis of the shovel head  12  as in  FIG. 3 , the sifting shovel  10  will tend to pivot automatically upon the resting of the handle  14  on a support surface. 
   An alternative construction of a sifting shovel  10  pursuant to the instant invention is depicted in  FIGS. 3 and 4 . There, the sifting shovel  10  again has a shovel head  12 . The shovel head  12  has a base plate  28  with first and second side walls  20  and  22  and a rear wall  24  perpendicularly fixed thereto to define a reception volume. A sifting plate  18  is fixed to the upper edges of the first and second side walls  20  and  22  and the rear wall  24  in spaced relation relative to the base plate  16 . The sifting plate  18  could be in a plane parallel to a plane of the base plate  16 , or, as is shown in  FIGS. 3 and 4 , the sifting plate  18  and the base plate  16  can be disposed in a truncated wedge configuration with the separation between the sifting plate  18  and the base plate  16  increasing from the distal to proximal ends of the shovel head  12 . 
   An elongate handle  14 , which can be round, with a hook portion  32  again has a proximal end fixed to the rear wall  24  of the shovel head  12 . Furthermore, a plurality of apertures  26  are disposed in the sifting plate  18  for enabling ash, dust, and sufficiently small debris to sift therethrough and into the reception volume for being removed from the combustion area. The distal ends of the sifting plate  18 , the base plate  16 , and the first and second side walls  20  and  22  again together define an open mouth  28  of the shovel head  12 . The open mouth  28  can again have a minimum opening height H greater than the maximum aperture dimension A thereby to ensure that debris being received into the reception volume, whether through the open mouth  28  or through the apertures  26 , can be dispensed through the open mouth  28 . 
   In the present embodiment, however, the apertures  26  are substantially round in configuration and are substantially consistent in size. With this, the maximum aperture dimension A is defined by the aperture diameter. The construction of  FIGS. 3 and 4  also varies in that the handle  14  does not have a bend therein but instead extends along a centerline that establishes a pivot axis PA that is generally parallel to, but below, a longitudinal center of gravity COG of the sifting shovel  10  as a whole. Under this arrangement, the lower portion of the handle  14  can be rested on a support surface, such as the rim of a refuse container (not shown), and, due to the pivot axis PA being below the longitudinal center of gravity COG of the sifting shovel, gravity will tend to induce an automatic flipping of the sifting shovel  10  with a concomitant discharge of any ash, dust, or other material retained therein. 
   With certain details and embodiments of the present invention for a sifting shovel disclosed, it will be appreciated by one skilled in the art that numerous changes and additions could be made thereto without deviating from the spirit or scope of the invention. This is particularly true when one bears in mind that the presently preferred embodiments merely exemplify the broader invention revealed herein. Accordingly, it will be clear that those with the major features of the invention in mind could craft embodiments that incorporate those major features while not incorporating all of the features included in the preferred embodiments. 
   Therefore, the following claims are intended to define the scope of protection to be afforded to the inventor. Those claims shall be deemed to include equivalent constructions insofar as they do not depart from the spirit and scope of the invention. It must be further noted that a plurality of the following claims express certain elements as means for performing a specific function, at times without the recital of structure or material. As the law demands, these claims shall be construed to cover not only the corresponding structure and material expressly described in this specification but also all equivalents thereof whether now known or hereafter discovered.