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CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    Pursuant to Title 35 USC §119(e), this is a non-provisional patent application and claims the benefit of U.S. provisional patent application Ser. No. 61/565,555, filed Dec. 1, 2011, the contents of which are incorporated herein by reference 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    This invention relates to an apparatus for removing snow from a surface. More particularly, the invention relates to an apparatus for removing snow from a roof of a house or other structure. 
         [0004]    2. Description of the Related Art 
         [0005]    Water leaks through the roof of a dwelling during winter are often the result of ice damming. Ice dams occur when water from melting snow freezes near the edge of a roof, such as a gutter line, and traps other melt water behind it. This water can run back up under shingles or sheathing and leak into the house. Snow melt may be caused by fluctuating ambient weather conditions or from heat escaping from inside the dwelling. One way of preventing ice damming is to remove snow from the roof before the snow melts. To avoid the risks associated with climbing onto the roof, snow rakes have been developed which can be manipulated by a user on the ground. 
         [0006]    Conventional snow rakes include an elongate handle and a blade disposed at the distal end of the handle. A user standing on the ground grasps the snow rake by the handle, and maneuvers the blade to a position on the roof several feet above the edge of a pitched roof. The blade is disposed transversely to the pitch or fall-line of the roof. Then, the user pulls on the handle to move the blade toward the user and down the pitch of the roof. As the blade moves, snow is scraped from the roof and falls to the ground or underlying surface. Depending upon the depth of the snow, several passes may be necessary to remove sufficient snow from the roofs to reduce the likelihood of ice damming. 
         [0007]    Because conventional snow rakes have a fixed single piece blade, it is difficult to navigate and clear snow from those sections of the roof where valleys occur. Snow rakes with flat blades are incapable of adequately clearing snow from a valley. Conventional fixed blade snow rakes must be maneuvered both down the pitch as well as in a direction laterally perpendicular thereto to move the snow down the roof valley. Often it is very difficult for the user many feet below the position of the blade to move the blade in such a manner, resulting in excessive snow built up to remain the roof valley where ice damming can occur. It would thus be desirable to have a tool which can more efficiently be used to clear snow from a roof and well as a roof valley without using two tools. 
       SUMMARY OF THE INVENTION 
       [0008]    One embodiment of the inventive snow rake includes a handle portion and a plurality of scraper blades which are angularly adjustable relative to one another; wherein the plurality of scraper blades are attached to said handle. 
         [0009]    Another embodiment of the invention disclosed herein comprises a handle, and a plurality of scraper blades attached to the handle wherein the blades rotate about the handle portion allowing the blades to form an angle relative to one another. The blades further being supported by a plurality of support bars which are affixed to the scraper blade at one end, and rotationally attached to the handle at the other. The device may further contain a weighted pole or rod attached to the handle portion of the device. 
         [0010]    Yet another embodiment of the snow rake comprises a handle assembly. A plurality of scraper blades are attached to one end of the handle assembly where at least one of the scraper blades is moveable between a first and a second position in a plane generally parallel to the other scraper blade and generally perpendicular to the axis defined by said handle assembly. The snow rake preferably includes at least one member for retaining the scraper blades on the end of the handle assembly, and at least one support brace or rotational guide interconnecting each of the scraper blades to the handle assembly. The invention may also allow all of the scraper blades to be moveable relative to one another to provide greater flexibility if fixing the desired angular orientation of the blades. To keep the blades in a fixed position, it is also contemplated that the snow rake include a rotational lock that may be separate or integral with the member for keeping the blades on the end of the handle assembly. 
         [0011]    In another form of the invention, the snow rake includes a handle assembly, a plurality of scraper blades disposed on an end of the handle assembly so as to pivot about an axis defined by the handle assembly, and a rotational lock assembly extending through the scraper blades for fixing a relative position of one or more of the scraper blades relative to another ranging between zero degrees and less than 180 degrees. The snow rake may further include an assembly for retaining the scraper blades proximate the end of the handle assembly, a rotational guide disposed along the handle assembly distal from the end, and interconnected to the scraper blades for transferring a load from the scraper blades to the handle assembly. The rotational guides may be comprised of a support brace interconnecting each of the scraper blades to the handle assembly and moveable with each of said plurality of scraper blades. In another form, the rotational guide may be comprised of a flange received along the handle assembly that is interconnected by a brace to the scraper blades. 
         [0012]    Yet another form of snow rake includes a handle assembly having a first end and a second end; a collar member received on the handle assembly and fixed in position proximate the first end; a plurality of blades, each having one end received over the first end and on to the handle assembly, positioned intermediate the collar member and the first end of the handle assembly; a rotational lock member received over the first end and attached to the handle assembly; and a rotational guide having a first end received along the handle assembly and a second end attached to one of the plurality of blades. In this configuration, at least one of the blades is able to pivot about an axis defined by the handle assembly between a first position and a second position relative to another of said plurality of blades, and fixed in position during use. 
         [0013]    Different geometries of the components of this invention may be utilized in accordance with this invention, for instance various shaped blades are anticipated to be used with this invention. Further, various sizes and styles of extension poles are anticipated for use with this invention. The examples above are provided to enable the invention and should not be read to be limiting. The foregoing and other objects, features, and advantages of the invention will become more apparent from the following description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         [0014]    Various illustrative systems, methods, devices, features, and advantages of the invention are described below with reference to the appended drawings, which may not be drawn to scale and in which like parts are designated by like reference designations, wherein: 
           [0015]      FIG. 1  is a perspective view of a first embodiment of the inventive snow rake; 
           [0016]      FIG. 2  is a plan view of the invention shown in  FIG. 1 ; 
           [0017]      FIG. 3  is a detail view of Section A shown in  FIG. 2 ; 
           [0018]      FIG. 4  is a plan view of a rotational guide flange shown in  FIG. 3 ; 
           [0019]      FIG. 5  is an elevation view of the rotational flange; 
           [0020]      FIG. 6  is a side view of the rotational flange; 
           [0021]      FIG. 7  is a plan view of one embodiment of a support brace; 
           [0022]      FIG. 8  is an elevation view of the support brace shown in  FIG. 7 ; 
           [0023]      FIG. 9  is a detail view of Section B shown in  FIG. 2 ; 
           [0024]      FIG. 10  is a front view of one embodiment of a rotational lock; 
           [0025]      FIG. 11  is a side view of the rotational lock shown in  FIG. 10 ; 
           [0026]      FIG. 12  is an elevation view of one embodiment of a handle assembly; 
           [0027]      FIG. 13  is a plan view of the handle shown in  FIG. 12 ; 
           [0028]      FIG. 14  is a front view of the handle assembly shown in  FIG. 12 ; 
           [0029]      FIG. 15  is a detail view of Section C shown in  FIG. 14 ; 
           [0030]      FIG. 16  is a front view of one embodiment of a blade; 
           [0031]      FIG. 17  is a side view of the blade shown in  FIG. 16 ; 
           [0032]      FIG. 18  is a front view of a second blade; 
           [0033]      FIG. 19  is a side view of the second shown in  FIG. 18 ; 
           [0034]      FIG. 20  is an elevation view of the snow rake assembly; 
           [0035]      FIG. 21  is front view of the snow rake assembly; 
           [0036]      FIG. 22  is a plan view of another embodiment of the invention; 
           [0037]      FIG. 23  illustrates another embodiment of the integral rotational guide and support brace; 
           [0038]      FIG. 24  illustrate another embodiment of the rotational lock member. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0039]    When referring to the drawing figures, like reference numerals designate like components even though the figures may illustrate variations or alternate embodiments of the invention. The embodiments illustrated and discussed herein are presented for the sole purpose of enabling one to make and use the invention. The description is not exhaustive and should not be understood as limiting in any way unless expressly stated. It should also be understood that the specific structures, devices, and structures illustrated in the accompanying drawing figures and described in the following specification are simply exemplary embodiments of the concept described herein and defined in the appended claims. Specific dimensions and other physical characteristics relating to the different embodiments described shall not be considered limiting, unless expressly stated otherwise in the specification or the claims. 
         [0040]    The invention described herein is directed to an improved snow rake, and more particularly to a snow rake having one blade that may be angularly adjusted relative to a fixed blade. One embodiment of such a snow rake  30  with angularly adjustable blades is shown in  FIG. 1 . The snow rake assembly  30  includes a handle assembly  32 , a blade support/rotational lock member  34 , and a plurality of scraper blades shown generally as  36 . The scraper blades  36  are interconnected to, and supported by, rotational guide  38  shown in  FIGS. 2 and 3 . Interconnecting the scraper blades  36  to the rotational guide  38  are support braces  40  extending between the blades  36  and the handle assembly  32 . 
         [0041]    Rotational guide  38 , shown in  FIGS. 3-6 , includes an annular flange  42  received along shaft  44  of the handle assembly  32 . Annular flange  42  is supported by a retention feature  46 , which in  FIG. 3  is formed by a depression  48  formed in the shaft  44  of handle  32 . Any one of a number of different fasteners may be used in association with depression  48  such as described in greater detail below. A fastener such as one selected from the group of screws, bolts, pop-rivets, spring-loaded pins, or spot welds may be used so long as the annular flange  42  is free to rotate about the handle assembly  32 . 
         [0042]    Referring now to  FIGS. 4-6 , annular flange  42  may be of a teardrop or other eccentric shape  50  and include a bent tab  52 . In one embodiment, the tab may be disposed at an angle between 30 degrees and 60 degrees, and preferably around 45 degrees relative to the plane of the annular flange. Through-holes  56  and  58  pierce annular flange  42  allowing the handle assembly&#39;s shaft  44  to pass through the larger hole  56  while the smaller hole  58  receives a fastener capable of mounting a support brace  40  such as shown in the embodiment in  FIGS. 7 and 8 . 
         [0043]    The intermediate support braces  40  interconnect annular flange  42  and scraper blades  36  to transfer loads placed upon scraper blades  36  to the shaft  44  of the handle assembly  32 . One form of a support brace  40 , shown in  FIGS. 7 and 8 , is comprised of a body portion  60  largely rectangular in shape and includes two mounting holes  62  and  64  disposed at opposite ends of the body  60 . A portion of the support brace  40  may also include a bent leg or arm portion  66 . In the instance shown in  FIG. 7-8 , the leg or arm  66  lies at about a 45 degree angle to align with and mount to the scraper blade  36 . Alternate forms of the support brace  40  may be formed of tubular, twisted, square, or round stock, with or without flattened ends. 
         [0044]      FIGS. 9-11  better illustrate the attachment of blade support  34  to handle assembly  32 . In one embodiment of the invention, blade support  34  may be comprised of a tear-drop or eccentric-shaped flange  50  similar to that of annular flange  42 . In this structure, tab  68  remains in the plane of the flange. Blade support  34  includes two holes formed therein; a shaft attachment hole  70 , and an angular retention hole  72 . Shaft attachment hole  70  is sized to be slightly larger than the outside diameter of the handle assembly shaft  44  allowing it to pass over the shaft and fixed in position, preferably by a fillet weld placed on a peripheral edge  74  of shaft attachment hole  70 . Alternatively the blade support  34  may be held in position by a pin or similar fastener extending transversely through the end of the handle assembly. Angular retention hole receives a fastener which also extends through an arcuate port formed in each of the blades to fix or lock the angular position of the blades relative to one another. For simplification, the blade support shall be referred to below as the rotational lock member. 
         [0045]      FIGS. 12-14  illustrate one embodiment of the handle assembly  32 , including an attached blade support  34 . Handle assembly shaft  44  may include an angled portion  76  designed to aid the user in positioning the handle assembly  32  for use on a roof. The user&#39;s end  78  of the handle may further be adapted to fit one or more optional extension poles. One manner of attaching extensions poles to the handle assembly  32  is to manufacture the handle assembly  32  from hollow tubular stock  80 . The extension pole is then sized to allow it to be inserted into the handle&#39;s hollow tubular stock  80 . One or more retention features  82  such as a hole  84  may be formed in and extend through the user&#39;s end  78  of handle assembly shaft  44  to fasten the handle extension to the shaft. One example of such a retention feature  82  may include a spring loaded button which passes into and locks with hole  84  when the extension pole is fitted to the shaft  44 . The extension poles may additionally contain counterweights to offset the weight of the snow rake  30  at the moment arm, thereby balancing it in the user&#39;s hands. 
         [0046]    Scraper blades  36  ( FIGS. 16-19 ) are designed to be positioned angularly relatively to one another. One embodiment of a scraper blade  86  includes a bent tabular flange  88  disposed toward the an upper edge  90  of the blade which provides structural stiffness to the scraper blade  86  and helps prevent snow from passing over the top of the blade during use. Flange  88  may be disposed at an angle of around 45 degrees, although other angular orientations may be chosen. Blade  86  shown in  FIGS. 16-17  differs from the scraper blade  92  shown in  FIGS. 18 and 19  in that it is a mirror image of the blade  86  shown in  FIGS. 17 and 19 . While the snow rake scraper blades need not be identical, one preferred embodiment of the invention uses the common shape to reduce costs. 
         [0047]    Referring again to  FIGS. 16-19 , body portion  96  of the scraper blades  86  include a support mounting hole  98 , an arcuate slot  100 , and an attachment hole  102 . The support mounting hole  98  is for attaching support brace  40  to the scraper blade  86 . Likewise, attachment hole  102  in scraper blade  86  is used to attach to the end of the handle assembly&#39;s shaft  44 . Attachment hole  102  is ideally sized to be slightly larger in diameter than shaft  44  so as to rotate freely about the shaft  44  when assembled. Arcuate slot  100  aligns with the outer smaller hole in the rotational lock and provides a method for attaching scraper blades ( 86 ,  92 ) to one other and to fix the relative angle between the blades. Arcuate slot  100  is radially centered about attachment hole  102  and limits the range of angular orientation of the blades relative to each other. In the embodiment of the invention shown in  FIG. 16 , arcuate slot  100  is positioned to allow approximately 45 degrees of angular adjustment. Thus when the arcuate slots of the blades ( 86 ,  92 ) are fastened to one another, the two arcuate slots allows for greater than the 45 degrees of rotation by one blade. In this instance, with two scraper blades, the assembly may have a fixed angular orientation between 0 and 90 degrees. The scraper blade&#39;s angular position may be temporarily fixed relative to blade  92  through the use a wing nut and a carriage bolt combination fixed in and passing through arcuate slot  100  and through the rotational lock flange  34 . 
         [0048]    In another form of the invention, scraper blade  86  may include a tapered portion  104  extending from edge  90  of the tabular flange  88  and extending toward corner  108  above the arcuate slot  100 . The tapered portion  104  of the blade  86  is not flanged and provides clearance between the tops of the scraper blades ( 86 ,  92 ) throughout their full range of rotation. Corners  106 ,  108 ,  110 , and  112  may contain radiuses in order to reduce the chance the underlying surface is penetrated. Corner  106  in particular may contain a larger radius  114 , such that when the scraper blades  86  are angled relatively to one another, corner radius  114  is presented toward the underlying surface. This allows the corner radius  114  to fit better into the roof valley formed by intersecting roof surfaces or pitches. In one embodiment of the invention, radius  114  is sized such that when the blades are placed parallel to one another, the radius  114  is complexly covered by the radius  114  on an adjacent blade, presenting no gap between the two scraping surfaces  116  along the length of the blade  118 . 
         [0049]    In another form of the invention, an optional edge protector, such as a plastic or rubber U-Shaped channel may be fit over the scraping surfaces  116  along the length of the blade  118  thereby protecting the roof surface when the scraping surface  116  is drawn across a roof surface. However, in order to accommodate the ability of the blades to be angularly adjusted relatively to one another, the optional edge protector ideally will be placed only along the length of the blade  118  and will exclude the radiused portion  114  of corner  106 . 
         [0050]    In another embodiment of the invention shown in  FIGS. 22-24 , it is contemplated that parts may be combined. For example, the rotational guide described above may be integral with a support braces to create a single piece shown by reference numeral  120 . The integral rotational guide  120  not only provide a means for transferring loads from the blades to the handle assembly, but they also act to maintain the blades in their relative position to one another and to the longitudinal axis represented by the handle assembly. It is also contemplated in this alternate embodiment that the blades may be retained on the end of the handle assembly by a collar  122  received over the handle assembly  124  and fixed in position by a fastener  126  such as a cotter pin, screw, bolt, or the like passing through the handle. The collar  122  together with the rotational lock/blade support  128  sandwiches the blades there between and prevents the blades from sliding down the handle assembly. Alternatively the collar may be dispensed with and solely the fastener such as a cotter pin, hitch pin, or e-clip may extend through or around the end of the handle to keep the rotational lock in position. The rotational lock  128  may include use a split-O or mirror D-shaped openings  130  that are received within a corresponding slot  132  formed in the end  134  of the end of the handle assembly  124  to keep the rotational lock  128  in position. With respect to anchoring the rotational guides  136  along the handle  124 , the same type of collars  122  described above may be used to fix the position of the annular end  138  of the rotational guide  134  or annular flanges at the ends of the braces to the handle assembly  124  and transfer the load on the blades to the handle assembly. Cotter pins are like fasteners  140  may extend through each of the collars and the handle assembly to keep them in position. 
         [0051]    In operation, the user determines the area of the roof where the snow is to be removed. The user releases the fastener fixing the angular orientation of the scraping blades to set the proper angle, retightening the fastener. The user decides whether any extensions to the snow rake handle assembly are required. With the snow rake in the desired configuration, the user grasps the handle to place the blades upon the desired location on the roof. Pulling the handle, the snow rake scraps the volume of snow in front of the scraping blades toward the roof edge where it falls and off of the roof. The steps are repeated until all of the snow along the desired section of the roof is plowed. 
         [0052]    The above descriptions are considered that of the preferred embodiments only. Modifications of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the doctrine of equivalents. The embodiments of the invention in which an exclusive property or privilege is claimed are defined below. 
         [0053]    Having now described the features, discoveries and principles of the invention, the manner in which the invention is constructed and operated, the characteristics of the invention, and the advantageous, new and useful results obtained; the new and useful structures, devices, elements, arrangements, parts and combinations are set forth in the appended claim.

Summary:
The invention disclosed herein comprises a snow rake for use in removing snow from a roof. The snow rake comprises a handle, a plurality of scraper blades attached to the handle wherein the blades can pivot between a first and a second angle. The snow rake blades are further supported by a plurality of rotational guides rotationally attached to the handle. The snow rake may further include a weighted pole or rod attached to the handle portion of the device to offset the weight of the blades when extended some distance from the user.