Patent Publication Number: US-2004055184-A1

Title: Snow rake

Description:
FIELD OF THE INVENTION  
       [0001] The present invention pertains to snow rakes. In particular, the present invention pertains to a snow rake including a low friction lubricious sheath or a pivotably mounted blade.  
       BACKGROUND OF THE INVENTION  
       [0002] 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 the shingles and rot the wood sheathing and leak into the house. Snow melt can be caused by ambient weather conditions or from heat escaping from the house. One way of preventing ice damming is removing 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.  
       [0003] Conventional snow rakes include an elongate handle and a blade disposed at the distal end of the handle. A user standing on the ground can lift the handle such that the blade is disposed 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 handle is pulled proximally toward the user. This drags the blade down the roof. As the blade is dragged down the roof, snow is scraped from the roof and falls downward. Depending upon the depth of the snow, several passes will be necessary to skim off successive layers of snow. After successive layers of snow have been skimmed off from a particular portion of the roof, until the roof is exposed, then the user can move the rake to another portion of the roof.  
       [0004] As several layers of snow must generally be skimmed off before an area of a roof is cleared or exposed, clearing a roof with a conventional snow rake can be a time consuming chore. It would thus be desirable to have a tool which can more efficiently be used to clear snow from a roof.  
       SUMMARY OF THE INVENTION  
       [0005] The present invention pertains to a snow rake for removing snow from a roof. The snow rake includes an elongate handle and a blade disposed at the distal end thereof. The blade extends transversely to the handle. An opening extends through the blade. A bottom portion of the blade is preferably sharpened to create a frost edge. Extending distally from the blade is a partially coiled, low friction lubricious sheath.  
       [0006] A user standing on the ground glides the blade several feet above the edge of a pitched roof. The blade is then drawn downward, slicing through the snow, until it reaches the surface of the roof. As the blade is drawn through the snow, most of the snow passes through the opening, remaining in place on the roof. The lubricious sheath, however, is uncoiled beneath snow as the blade is dragged downward. Once the sheath is disposed between the roof surface and the snow, the relatively high frictional interface between the snow and the roof is replaced by a low friction interface between the snow and the sheath. The snow then readily slides downward off the roof.  
       [0007] In a second embodiment of the invention, a snow rake comprises a handle pivotably attached to a snow-removing blade. The blade is slide up the roof in a closed position. When the snow rake is then drawn back down the roof, the blade pivots to an open position, allowing the user to pull snow down the roof. Rollers or skis may be attached to the edge of the blade to permit the blade to more easily slide down the roof.  
       [0008] An embodiment of the invention pertains to a means for packaging the invention for easy and compact storage. The handle may comprise several sections that may be retained together using two end caps connected by an elastic cord. This elastic cord may also be used to retain the frame or blade against the handle sections. A clip may be attached by a cord to one of the end caps for this purpose as well. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0009]FIG. 1 is a perspective view of a snow rake in accordance with the present invention;  
     [0010]FIG. 2 a  is a side view of a stay in accordance with the present invention;  
     [0011]FIG. 2 b  is a side view of an end of the stay connected to the snow rake;  
     [0012]FIG. 2 c  is a side view of the opposite end of the stay connected to the snow rake;  
     [0013]FIG. 3 is a partially exploded perspective view of a portion of a snow rake;  
     [0014]FIG. 4 is a perspective view of a blade of a snow rake illustrating several wheel configurations;  
     [0015]FIG. 5 is a side view of the snow rake;  
     [0016]FIG. 6 is a detail view of the blade of the snow rake;  
     [0017]FIG. 7 is a side view of the handle of the snow rake;  
     [0018]FIG. 8 is a side view of a tubular coupling for coupling the handle to the snow rake;  
     [0019]FIG. 9 is an end view of the tubular coupling;  
     [0020]FIG. 10 is a perspective view of a snow rake in accordance with the present invention;  
     [0021]FIG. 11 is a perspective view of a snow rake in accordance with the present invention; and  
     [0022]FIG. 12 is a perspective view of a snow rake in packaging in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     [0023] The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered in like fashion. The drawings which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. In some cases, the drawings may be highly diagrammatic in nature. Examples of constructions, materials, dimensions, and manufacturing processes are provided for various elements. Those skilled in the art will recognize that many of the examples provided have suitable alternatives which may be utilized.  
     [0024] Referring now to the drawings, FIG. 1 is a side view of a snow rake  10  in accordance with the present invention. Snow rake  10  includes an elongate handle  12 . Disposed near one end of handle  12  is a blade  14 . Blade  14  can have a generally rectangular opening  15  therethrough. Extending from blade  14  is a partially coiled lubricious sheet  16 .  
     [0025] Handle  12  has a distal end  18 . Handle  12  is preferably 10 to 20 feet long, or longer as is necessary to reach the roof of a structure. Handle  12  may be made from a single, elongate rod, a telescoping rod, or a rod which comes in several segments which can be connected together to create a handle  12  of sufficient length.  
     [0026] Blade  14  preferably includes a tubular coupling  20  through which handle  12  can extend. Blade  14  also includes a bottom portion  26  or sheet attaching member. It can be appreciated, by reference to subsequent figures that blade  14  has a rectangular configuration extending transversely to handle  12 . Top portion  24  and bottom portion  26  define the top and bottom of an opening extending through blade  14 . Bottom portion  26  includes a proximal edge  28 . A leading portion  33  of sheet  16  can be disposed under bottom portion  26  and fastened thereto by screw or other fastener. Blade  14  is preferably made from a light metal, such as aluminum or plastic.  
     [0027] Sheet  16  is preferably biased into a partially coiled configuration including at least one curved portion  34  disposed between a leading edge  33  and a distal edge  36  of sheet  16 . Sheet  16  is preferably formed such that it is internally biased to recoil if straightened. Lubricious sheet  16  preferably comprises a material which is durable, light weight, and provides a surface having a relatively low coefficient of friction. Examples of materials which may be suitable in some applications include: polyolefin, polyvinylchloride (PVC), polyurethane, polytetrafluoroethylene (PTFE), polyamide, and polyimide. Examples of polyolefins which may be suitable in some applications include polyethylene (PE) and polypropylene (PP). In a preferred embodiment, sheet  16  has a thickness between about 0.020 inches and 0.080 inches.  
     [0028] In FIG. 1, sheet  16  of snow rake  10  is disposed in an uncoiled position A. Sheet  16  may also assume a substantially coiled position B (See FIG. 2). For example, blade  14  may be drawn downward, slicing through a layer of snow disposed on a roof. As blade  14  is drawn through the snow, sheet  16  will be uncoiled beneath a substantial portion of the snow as blade  14  is dragged downward. Once sheet  16  is disposed between the roof surface and the snow, the relatively high frictional interface between the snow and the roof is replaced by a low friction interface between the snow and sheet  16 . The snow then readily slides downward off the roof.  
     [0029] In an embodiment, sheet  16  is biased to assume position B when there are no outside forces (e.g., the weight of the snow) acting on it. Alternately, stays  40  may be releasably or permanently connected to blade  14  and proximate a distal edge  36  of sheet  16  to maintain sheet  16  in the uncoiled, or at least partially uncoiled position A. Stays  40  might be used, for example, when the weight of the snow encountered by rake  10  is insufficient to move sheet  16  from the coiled position B to the uncoiled position A.  
     [0030]FIG. 2 a  is a side view of stay  40 . Stay  40  may be formed from a metal such as steel, aluminum or a polymer. It should be sufficiently rigid to resist the bias of sheet  16  to move from uncoiled position A to coiled position B. Each end of stays  40  may be bent to form an angle  46 . At one end of stay  40  may be releasably inserted into an opening  42  in blade  14  as shown in FIG. 2 b . Angle  46  at the opposite end of stay  40  may be releasably inserted into an opening  44  in sheet  16  as shown in FIG. 2 c.    
     [0031]FIG. 3 depicts a partially exploded perspective view of a blade and sheet portion of a snow rake. A spacer  15  may be attached to bottom portion  26 , over leading portion  33  of sheet  16 . Spacer  15  generally extends over the width of bottom portion  26  and comprises plastic or another durable, non-abrasive material that is suitable. Spacer  15  may have holes  17  aligned with holes in sheet  16  and blade  14  for fastening the three pieces together using screws, rivets or other suitable fasteners. Longitudinally aligned risers  19  may be interspersed between holes  17  to lift metal or abrasive components away from the roof. Risers  19  may have a curved outer surface to facilitate travel over the roof. Alternatively, a single curved riser  19  may extend over the entire surface of spacer  15 , with holes  17  countersunk therein. In another contemplated alternative, fasteners may be integrally manufactured with spacer  15 , thereby eliminating metal fasteners and permitting blade  14  and sheet  16  to snap together with spacer  15 .  
     [0032]FIG. 4 depicts a blade  14  having several different configurations of wheels attached thereto. While any combination of wheels may be used, embodiments are contemplated having only one wheel configuration. For example, blade  14  may have wheels to ease its travel down the roof. Wheels  21  may be two or more wide wheels  21  installed in bottom portion  26  of blade  14 . Alternatively, blade  14  may have a plurality of narrow wheels  23  imbedded into blade  14 . Of course, wheels  21  or wheels  23  may be installed on a leading or trailing edge of blade  14 , rather than in the middle, as depicted. In another contemplated alternative, a pair of larger, narrow wheels  25  may be installed on the sides of blade  14 .  
     [0033] It can be appreciated that sheet  16  defines a gliding surface  35 . When snow rake  10  is being utilized to clear snow from a roof, gliding surface  35  may be utilized to assist in positioning snow rake  10 . For example, the distal end of snow rake  10  may be lifted to a location proximate the lowest portion of the roof. Snow rake  10  may then be lowered until gliding surface  35  of sheet  16  contacts the roof or a layer of snow overlaying the roof. It may be appreciated that resting gliding surface  35  on the roof will significantly reduce the force required from the person using the roof rake. The distal end of snow rake  10  may be advanced to a higher location of the roof by pushing distally on handle  12  and allowing gliding surface  35  to slide along the roof or a layer of snow overlaying the roof.  
     [0034] Leading portion  33  of sheet  16  can be rotationally fixed relative to blade  14 . FIG. 5 is a side view of snow rake  10  showing sheet  16  connected by fasteners  32 , such as a screw, underneath bottom portion  26  of blade  14 . As can be seen in FIG. 5, leading portion  33  of sheet  16  can be biased to curve upward.  
     [0035] In FIG. 5 tubular coupling  20  can be seen connected to top portion  24  of blade  16 . This connection can be made by welding or other connection or fastening techniques. Handle  12  is shown disposed in and releasably connected to tubular coupling  20  by detent  48 . Detent  48  is biased into position by a spring  50 .  
     [0036]FIG. 6 is a detail of the connection of sheet  16  to blade  14 . Fastener  32  is shown as a threaded fastener. Numerous other connections or fastening techniques could be used to secure sheet  16  to blade  14 .  
     [0037]FIG. 7 is a side view of handle  12 . Detent  48  is outwardly biased by spring  52 . Handle  12  can have a reduced diameter portion  53  where it is inserted into tubular coupling  20 . Proximate the end of handle  12  near blade  14 , handle  12  can have an ergonomic bend  55 .  
     [0038]FIG. 8 is a side view detail of tubular coupling  20 . Tubular coupling  20  can have an opening  54  for receipt of detent  48 . Coupling  20  can also have a detent guide  56  to facilitate alignment of detent  48  in tubular coupling  20 .  
     [0039]FIG. 9 is an end view of tubular coupling  20 . When handle  12  is connected to coupling  20 , detent  48  can be deflected inward and slid into detent guide  56  until detent  48  is biased into opening  54 . This will releasably secure to your handle  12  to blade  14 .  
     [0040]FIG. 10 is a perspective view of a snow removal rake  10  according to the invention. Handle  12  is pivotably attached to a blade  14  having a relatively large surface area and which may have a curved surface. Reinforcing arms  58  may also be pivotably attached to the blade and slideably attached to handle  12 . This attachment between reinforcing arms  58  and handle  12  may comprising a bar connecting reinforcing arms  58  that is disposed in an elongate slot having two opposing openings. This configuration permits blade  14  to move between a closed position, in which there is a minimum distance between blade  14  and handle  12 , and an open position, in which there is a maximum distance between blade  14  and handle  12 . When the blade is in the open position, it may be substantially perpendicular to the handle or there may be an acute angle between the handle and the blade. The blade is disposed to be in the closed position when the blade end of the snow rake is pushed up a roof. When the snow rake is drawn down the roof, the blade digs into the snow, moving to the open position. The pivoting ends of handle  12  and reinforcing arms  58  may be arranged in a triangular pattern on the blade. This permits the blade and the handle to be connected through an inherently stable tetrahedral joint. In this position, as the snow rake is drawn down the roof, snow is pushed down the roof as well. Blade  14  is made of a rigid material such as metal or plastic with reinforcing ribs. In addition, blade  14  may have a lubricious surface to aid in pushing the blade up the roof and into the snow. Working edge  60  of blade may be sharpened to help the blade more easily cut through the snow. Means for keeping the blade off the roof and easing the movement of the blade downward on the roof may be attached to edge  60 . These means may be rollers  62  or skis (shown and further discussed in FIG. 11).  
     [0041]FIG. 11 is a perspective view of a snow rake  10  according to the invention. The embodiment of FIG. 11 is similar to the embodiment of FIG. 10 except for the differences discussed herein below. Handle  12  and reinforcing arms  58  are fixedly attached to a foot portion  62  of blade  14 . Reinforcing arms are also fixedly attached to handle  12 . A pivotable portion  64  of blade is attached to base portion  62  through hinge  66 . This permits the snow rake to operate in substantially the same fashion as the embodiment of FIG. 10, where the blade slides up the roof in the closed position, and opens to push the snow down the roof when the snow rake is drawn down the roof. Attached to edge  60  of blade are one or more skis  68 . Skis  68  may be pivotably attached to edge  60  or they may be fixed. Skis  68  are configured so that when blade  14  is in the open position, the skis are substantially parallel to handle  12 , allowing the blade to be drawn down a roof without edge  60  catching on the roof.  
     [0042]FIG. 12 is a perspective view of a snow rake packaged according to the invention. It can well be appreciated that a smaller, more rigid package is easier to transport and store. If a snow rake has a handle  12  which comprises more than one segment, these segments  72  can be securely retained together using two caps  70  disposed on opposite ends of segments  72  connected by a cord  74 . These caps may be hollow for receiving the ends of the handle segments or may consist of a number of fingers, each finger being received by a hollow end of a handle segment. These caps may retain handle segments  72  in a bundled configuration or in a flat configuration, as depicted in the figure. Cord  74  may be elastic to more easily retain handle segments  72 . This cord may extend substantially directly between the first cap and the second cap or may retain the blade or blade and frame in a closed or rolled up position against handle segments  72 . In the alternative, a second cord  76  may be attached at one end to a cap  70  and to the other to a clip  78 . The blade  14  or blade and frame portion may be retained against handle segments  72  by cord  76  and clip  78 . Clip  78  is configured to clip onto one or more handle segments  72 . In this manner a snow rake can be reduced to a smaller, more manageable package for transporting or storing.  
     [0043] Numerous characteristics and advantages of the invention covered by this document have been set forth in the foregoing description. It will be understood, however, that this disclosure is, in many respects, only illustrative. Changes may be made in details, particularly in matters of shape, size and ordering of steps without exceeding the scope of the invention. The invention&#39;s scope is, of course, defined in the language in which the appended claims are expressed.