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FIELD AND BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates generally to the field of manual tools for snow removal and in particular to a new and useful snow shovel having an articulating shovel blade mounted to a carriage.  
           [0002]    Snow shovels having a blade and an elongated handle are generally well known in the art of snow removal tools. Some snow shovels have sharply curved blades, while others are flattened, and still others have side panels.  
           [0003]    Two types of shovel are particularly common, regardless of the specific blade or handle. One type is used to lift snow and throw it, while the other type of shovel is used primarily to push snow in front of it like a plow.  
           [0004]    It is also generally well known that some types of snow can be particularly heavy, such as wet, slushy snow or icy snow. Attempting to shovel a walkway or driveway covered with wet snow can be difficult for many people because of the weight.  
           [0005]    Many different solutions have been provided for making shoveling easier. Some of the solutions include adding a handle to a conventional single handle shovel, such as disclosed by U.S. Pat. No. 6,343,822. U.S. Pat. No. 6,343,822 teaches a shovel with a second, adjustable handle which can be moved from side to side around the main handle shaft to provide leverage for lifting snow or other material with the shovel.  
           [0006]    Other patents disclose handles and blades which pivot relative to each other. U.S. Pat. No. 6,290,273, for example, describes a shovel with a blade that pivots to a greater or lesser angle between the blade surface and the handle. That is, the shovel blade pivots up and down about a horizontal axis.  
           [0007]    U.S. Pat. No. 5,984,393 teaches a shovel having a fixed second handle near the shovel blade, and a mechanism for allowing the shovel blade to pivot about the main handle. The shovel blade is locked from pivoting until a load of snow has been lifted and is ready to be dumped. Then, a trigger is used to allow the blade to pivot to one side or the other so that the snow is dumped without having to twist the shovel handles.  
           [0008]    U.S. Pat. No. 813,983 discloses a shovel with the shovel blade pivotally attached to the handle so that the blade can tilt to the left or right. The blade is connected to the handle by two bolts or screws arranged vertically aligned. The upper bolt is mounted through an arcuate slot in the shovel blade, while the lower bolt is the pivot point. Thus, the edges of the blade can be tilted off horizontal, theoretically to cause snow to move to one side when the shovel is used as a plow. However, it appears that if the bottom edge is not flat, some snow would remain behind when using the shovel in this manner.  
           [0009]    A scoop shovel having the scoop blade horizontally pivotable about a vertical shaft axis is taught by U.S. Pat. No. 2,221,219. The scoop is moved by a ratchet and pawl mechanism connected to a remote lever at the end of the handle shaft. The scoop is pivotable for use scooping out ashes from a furnace having a small door, whereby the shovel can be inserted through the furnace door, pivoted, ashes scooped up and the scoop pivoted back for removal from the furnace.  
           [0010]    A snow plow type shovel having an expandable pushing blade is disclosed by U.S. Pat. No. 6,269,558. The blade has two adjustable wings connected to form a “V” with a flat bottom where the handle is attached. The wings can be pivoted to form a greater or smaller acute angle relative to the handle.  
           [0011]    U.S. Pat. No. 6,334,640 discloses a snow shovel having a rotating handle and a single wheel. The handle and wheel are connected to the center of the rear of the shovel blade, so that the shovel is symmetrical about a horizontal axis through the center. The handle can be rotated around the wheel so that the shovel can be f lipped over to permit the other edge of the shovel blade to contact the ground. The blade does not pivot horizontally relative to the wheel or handle.  
           [0012]    Each of the shovels having a pivoting blade still has the easiest direction of travel with the shovel being perpendicular to the surf ace of the shovel blade. Alternatively, these shovels result in the handle being positioned at an odd angle when the shovel blade is placed square on the ground, so that it will be difficult to move the shovel. That is, none of the prior shovels provides a means for angling the blade relative to the direction of movement of the shovel blade, so that it can truly act as a plow.  
         SUMMARY OF THE INVENTION  
         [0013]    It is an object of the present invention to provide a shovel having a pivoting blade for moving snow from a sidewalk or driveway.  
           [0014]    It is a further object of the invention to provide a shovel with an adjustably pivoted blade.  
           [0015]    Yet another object of the invention is to provide a wheeled shovel for more easily pushing snow off a driveway or sidewalk.  
           [0016]    Accordingly, a shovel is provided having an articulated shovel blade pivotally attached to a wheeled carriage. The shovel blade can be locked into three or more positions at different angles relative to a support bar of the carriage. The shovel blade is pivotally mounted to the support bar with a bracket so that the blade is spaced from the support bar and wheels of the carriage. A locking pin passing through the bracket and support bar is used to hold the bracket in position relative to the support bar. A handle extends upwardly from the support bar so that a person using the shovel can push it easily in a direction perpendicular to the support bar, even while the shovel blade is angled relative to the support bar.  
           [0017]    The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]    In the drawings:  
         [0019]    [0019]FIG. 1 is a top, rear perspective view of a snow shovel according to the invention;  
         [0020]    [0020]FIG. 2 is a magnified view of the joint between the bracket and support of the snow shovel of FIG. 1;  
         [0021]    [0021]FIG. 3 is a side elevation view of the shovel of FIG. 1 with the wheels and handle removed;  
         [0022]    [0022]FIG. 4 is a top plan view of an alternative support for the snow shovel of FIG. 1;  
         [0023]    [0023]FIG. 5 is a top plan view of a second embodiment of a snow shovel according to the invention; and  
         [0024]    [0024]FIG. 6 is a bottom plan view of a third embodiment of a snow shovel of the invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]    Referring now to the drawings, in which like reference numerals are used to refer to the same or similar elements, FIG. 1 shows an articulated shovel  10  of the invention with the handle  50  shown having a truncated length. The articulated shovel  10  has a pivotable shovel blade  20  connected to a support bar  35  of a carriage  30 . A bracket  25  pivotally secures the shovel blade  20  to the support bar  35 . The bracket  25  is joined to the support bar at pivot joint  36 . The other ends of the bracket  25  are riveted, welded or fastened with threaded fasteners to the shovel blade  20 .  
         [0026]    The carriage  30  includes support bar  35  extending between a pair of wheels  33  attached to the support bar  35  by axles  32 . A handle  50  extends upwardly and to the rear from either side of the support bar  35  in an inverted “U” for pushing the carriage  30  and shovel blade  20 .  
         [0027]    [0027]FIG. 2 illustrates the pivot joint  36  connection between the bracket  25  and support bar  35  in greater detail. As shown, the pivot joint  36  can be formed by a threaded bolt fastened through the support bar  35  and bracket  36  so as to permit rotational movement between them. When the pivot joint  36  can be non-destructively disassembled, storage of the shovel  10  is made easier, as the blade  20  can be removed to occupy less space.  
         [0028]    Alternatively, the pivot joint  36  may be formed by a permanent connector which is arranged to permit relative movement, such as a rivet loosely joining bracket  25  and support bar  35 , a bolt and locking cotter pin or a similar shaft and locking fastener combination.  
         [0029]    The pivot joint  36  is held in a pre-determined fixed position by a locking pin  38 . As best seen in FIGS. 2 and 3, a locking pin  38  is provided extending through one of the bracket holes  37  in the bracket  25  and a corresponding carriage hole in the support bar  35 . The locking pin  38  has a larger head than the diameter of the bracket holes  37  so that the upper end will not pass through the bracket hole  37  it is inserted into.  
         [0030]    A number of carriage holes through the support bar  35  are positioned to align with one or more of the bracket holes  37  when the bracket  25  and shovel blade  20  are pivoted to a particular position. The locking pin  38  is then dropped into place through an aligned pair of the bracket holes  37  and carriage holes. The locking pin  38  can be threaded at one end for fastening more securely through the aligned holes, or it may simply have a length sufficient to prevent it from rising out of the aligned holes during use. For example, an unthreaded locking pin  38  used with the shovel  10  may extend about ½ inch past the lower surface of the support bar  35 .  
         [0031]    The locking pin  38  prevents relative movement of the shovel blade  20  and carriage  30  during use. The shovel blade  20  is preferably positionable in at least three positions—left, right and center. The left and right positions orient the shovel blade  20  to push snow off to the side of the direction of travel of the carriage  30 , while the center position will push snow straight ahead in advance of the shovel  10 . By locking the shovel blade  20  position relative to the carriage  30 , the carriage  30  can be pushed straight forward while the shovel blade remains in a fixed orientation that can be oblique to the direction of travel.  
         [0032]    Referring again to FIG. 3, a side panel  35   a  of support bar  35  is shown having openings  34 ,  52  for receiving axles  32  and attaching the handle  50 , respectively. The axle opening  34  is preferably slotted so that the axle  32  may be fixed at different heights to permit adjustment of the shovel  10  for differences in the blade  20  size. Alternatively, the axle opening  34  can be a simple circular opening for receiving the axle  32  and affixing the wheel  33  thereto.  
         [0033]    The axles  32  are preferably shafts having a threaded end or hole at the end for passing through axle openings  34  and receiving a fastener such as a nut or cotter pin. The shafts permit free rotational movement of the wheels  33  in either direction, while holding them securely to the carriage  30 . Washers and other elements common to such connections may be used to improve the attachment of the wheels  33  to the carriage  30 .  
         [0034]    The handle attachment openings  52  are arranged so that ends of the handle  50  can be affixed using threaded connectors. Two openings  52  are provided to lend additional strength and rigidity to the connection, while orienting the handle  50  upwardly and to the rear.  
         [0035]    As seen in FIGS. 1 and 3, the bracket  25  can be either a single, unitary piece or two separate pieces joined together. Preferably, the bracket  25  is a single piece bent to form a generally “V”-shaped support with the free end of each arm secured to shovel blade  20 . The bracket  25  preferably lends support to the shovel blade  20  as well as holding it in place and preventing tilting of the blade forward and backward. While a single arm bracket  25  could be used, it is not preferred, so as to avoid undesirable movement of the shovel blade  20  relative to the carriage  30 .  
         [0036]    The arms of bracket  25  are made sufficiently long so that the shovel blade  20  does not impinge upon the wheels  33  when the blade is pivoted to the extreme left or right lockable position. The lengths of the bracket  25  and support bar  35 , width of the shovel blade  20 , and the diameter of the wheels  33  will all affect the length of the bracket  25  required to use the shovel blade  20  at a particular angle relative to the direction of travel of the carriage  30 . In a preferred embodiment, the wheels  33  have a diameter of about 4 inches, the support bar  35  is about 24 inches long, the shovel blade is about 30 inches wide and the support bracket  25  arms extend about 8 inches forward. The shovel blade  20  is preferably longer than the total length of the support bar  35  with the wheels  33 , so that snow directly ahead of the wheels  33  is removed to avoid leaving packed snow from the wheel tracks.  
         [0037]    The dimensions are preferably set to permit positioning the shovel blade  20  at left and right maximum angles of between 5-45°, and more preferably maximum angles between 15-35°. While the support bar  35  may have several carriage openings  39  for aligning with corresponding bracket openings  37 , preferably at least three carriage openings  39  are provided for holding the bracket  25  and shovel blade  20  at three different angles relative to the support bar  35 . The three angles are preferably one position being with the shovel blade  20  parallel to the support bar  35  and carriage  30  (centered), one position angled to the left at between 5-45°, and the third position angled to the right at between 5-45°. The carriage hole  39  positions to each side of center may be arranged symmetric or asymmetric, but symmetry is preferred so that the shovel is equally useful for either side.  
         [0038]    [0038]FIG. 4 illustrates an embodiment of the support bar  35  having five different carriage holes  39  for aligning with the bracket holes  37  to position the shovel blade  20 . The bracket  25  may include five bracket holes  37  (such shown in FIG. 5), each one aligning with a different one of the carriage holes  39 . Alternatively, the carriage holes  39  may all be positioned so as to align with a single bracket hole  37  for locking with a locking pin  38 .  
         [0039]    [0039]FIG. 5 shows an alternate embodiment of the shovel  10  in which handle  50  is connected extending from the top of support bar  35 . The handle  50  has an “I” or “T” shape, with a pair of handle grips  55  extending horizontally at the far end of handle shaft  57 . The bottom end of the handle  50  can be secured using wings  59  to attach to the support bar  35 . In a further alternative, the handle  50  does not include the horizontal handle grips, and instead has only handle shaft  57  extending upwardly to the rear of the shovel blade  20 , similar to a conventional shovel.  
         [0040]    A motorized version of the snow shovel  10  is illustrated in FIG. 6. The support bar  35  is shown looking at the bottom, where a motor  90  and battery  92  are mounted. A pair of wheels  33  are connected to the motor  90  by axles  80  for directly driving the wheels. The motor  90  is preferably an electric motor, but a gas powered motor may be used instead, and battery  92  can be replaced by a gas tank. The motor  90  is preferably activated by a switch  98  either mounted on the top surface of support bar  35  (not shown) or connected by a wire  95  and secured at the upper end of handle  50  for easier activation.  
         [0041]    The self-propelled snow shovel  10  shown in FIG. 6 is easily operated by persons of any strength with minimal effort. And, unlike a snow blower, the shovel  10  does not have any whirling blades which can present a significant hazard if not used properly.  
         [0042]    As seen in FIG. 6, wheels  33  are mounted inside the side panels  35   a  of the support bar  35 . The side panels  35   a  do not need to be present when the wheels are mounted to the motor  90 , but can be provided to shield the wheels  33 .  
         [0043]    As will be appreciated from the foregoing, both the manual and self-propelled versions of the shovel  10  are easily used to push snow from a driveway or walkway to the side of the area being cleared. The shovel blade  20  is oriented to one side or the other in a preferred mode of use, so as to direct snow to the so-angled side as the carriage  30  is moved straight forward. The shovel  10  permits the shovel blade  20  to be angled relative to the direction of movement without requiring a user to perform awkward movements. Similarly, a user need not strain to maintain the angled direction of the shovel blade  20  relative to the direction of travel.  
         [0044]    The shovel  10  is easily adjusted to change the angle of the blade  20  relative to the direction of travel as well. In the preferred embodiment, the locking pin  38  is removed, the blade  20  repositioned and the pin  38  reinserted in a different pair of aligned bracket and carriage holes  37 ,  39 .  
         [0045]    As can be understood from the foregoing, the shovel  10  is very easily dismantled and stored or parts are easily removed and replaced. The ease of replacement for each of the parts makes the shovel  10  economical, and, by replacing parts which wear more quickly, such as the blade  20 , the shovel  10  can have a long useful life. Further, the storage space occupied by the shovel  10  when it is taken apart is significantly less than when it is assembled ready for use.  
         [0046]    It should be noted as well that while the wheels  33  are shown at the outside ends of the support bar  35  in FIGS.  1 - 5 , they can also be mounted on axles  32  to the inside of side panels  35   a . The side panels  35   a  or similar depending support should be made sufficiently long to accommodate the wheel diameter selected for free rotation and avoiding contact with the support bar  35 .  
         [0047]    The carriage  30  may have more than two wheels  33  as well. For example, a rectangular frame including the support bar  35  may be used to mount three or four wheels to add stability to the shovel  10 .  
         [0048]    And, although the carriage  30  is shown as being manually motivated or having its own motor  90 , it is envisioned that the snow shovel blade  20  and bracket  25  can be mounted to the front of a self-propelled lawn mower. The bracket can be mounted using a support bar  35  and side panels  35   a  to position the shovel blade in a similar manner as with the wheeled carriage  30 . For example, the side panels  35   a  could attach to the self-propelled lawn mower at the front wheels.  
         [0049]    A different tool head could be substituted for the shovel blade  20  if desired, for use in other applications. For example, a rake head, a grader or a furrowing tool could be mounted to carriage  30  instead.  
         [0050]    While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

Summary:
A shovel has an articulated shovel blade for pivoting movement relative to a wheeled carriage on which the blade is mounted. The shovel blade is adjustably locked in position at different angles relative to the direction of travel of the carriage, for pushing snow or other material to the side of the shovel as it travels across the ground. The carriage is pushed forward using a handle or a motor is provided for self-propelling the carriage.