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TECHNICAL FIELD  
         [0001]    This invention relates in the majority to snow shovels or similar burden carrying devices having an auxiliary handle tethered in such a way as to be retractable to a conveniently stored disposition.  
         BACKGROUND OF INVENTION  
         [0002]    It is well known to those skilled in the art that ergonomic handle principles attempt to reduce bending of the lower back thereby reducing spinal injury. In the 1907 U.S. Pat. No. 845,592 to Stewart, we are taught that an upward bend in the handle located proximal to the shovel scoop will elevate the forward grip position reducing the curvature of the operators spine. We are also taught in the 1903 U.S. Pat. No. 725,905 to Williams, that lifting and carrying of a load is made easier if the forward grip position is moved directly above the load as described mathematically in mechanical moments of the laws of levers.  
           [0003]    In the 1909 U.S. Pat. 911,291 to Byor, we are shown that the forward grip position can be elevated to any height using an auxiliary grip with an adjustable resilient shank member with means for securing the same to the primary handle shaft. In the 1950 U.S. Pat. 2,521,441 to Bickley, we are taught that a flexible cord with terminating hand piece also elevates the forward hand grip point while improving the free universal action to throw material sideways and the mechanical efficiency of having the load placed directly under the hand grip point for lifting.  
           [0004]    The U.S. Pat. No. 4,200,324 to Helton, describes disposition methods of storage for grips tethered by means of flexible material using retaining holes or clips located on the primary handle.  
           [0005]    In U.S. Pat. No. 5,704,672 to Sims, the flexible cord is described as a resilient bungee cord which lengthens and shortens a portion of it&#39;s length to facilitate a smooth shoveling action but does not attempt to solve the problem of disposition. Like wise in U.S. Pat. No. 4,531,713 to Balboni, an elastic line lengthens and shortens to form a retrieval. Although prior art describes flexible means acting as ergonomic handles, the storage and disposition of said means of auxiliary handle is inconvenient and in the majority, prior art grips with flexible cord means are allowed to drag, impact, sag or traverse universally during the stroke of the tool. For a stand up shovel to be commercially accepted the auxiliary grip must be suitably arranged for convenience and the necessary elements defined so that the handle is advantageous and not obstructively placed to the traditional use of the shovel and as such, prior art has been unable to compose the necessary elements. Further, in a shovels introduction to the burden for loading and unloading, the flexible cord means should not cause the scoop to hover or bounce but should have a fixed length for elevating the load upwards on to a pile without having heavier loads cause the scoop to fall farther away towards the ground and the auxiliary grip should be completely and easily retracted safely out of the way when not in use.  
           [0006]    In addition to the advantages of reduced spinal curvature produced by a stand up shovel, a hand grip located for maximum mechanical efficiency and extensible through a low force biasing means from a comprehensible storage disposition has not been taught in prior art.  
           [0007]    Further, to facilitate a wide variety of dispensing locations for an extensible tethered grip, a pulley or sheave means described as a fixed curvature in Canadian Patent 2,188,956 to Stuart, teaches how non-rotating sheaves described as, curved surfaces or irregular contours, may act as guides to effect change in direction for dispensation of flexible string means such as polymer cordage or wire ropes.  
         DISCLOSURE OF INVENTION  
         [0008]    It is the primary purpose of the present invention to provide an ergonomic shovel handle in accordance with prior art for stand-up shovels which will include a readily accessible auxiliary hand grip easily withdrawn from a pocket located on the shovel.  
           [0009]    It is also a purpose of this invention to provide an opening substantially within the scoop area for the egress of a tether attached to said hand grip or in another form of this invention to provide an anchor point within the area of the scoop as a means of tethering an auxiliary grip.  
           [0010]    It is also a purpose of this invention to provide a curved surface and guiding means in preference of a freely rotating sheave within the primary handle to facilitate redirecting the tether towards the hand grip and from the anchor point. Said guiding means may be constructed to act as a blocking means to limit the extension length of the tether.  
           [0011]    It is a purpose of this invention to provide an anchor point, for a tension spring or longitudinally elastic element, substantially within the primary handle at a point distal from said egress and blocking means and substantially interposed of a “D” shaped grip located on the primary handle.  
           [0012]    In it&#39;s simplest form, according to the preferred elements of the present invention, said hand grip may be formed of a hollow cylinder interposed by a flexible string means looped to form an “A” shape as part of a tethering means of a return line which includes a biasing means at the opposite end At a point along the tethering means length is located a blocking means for the purpose of limiting the extension of the hand grip and indirectly lifting the scoop from a point behind the guiding means.  
           [0013]    It is also the purpose of the present invention to provide a holder or pocket for storage of the retracted hand grip within the embodiment of the shovel and in some cases strengthen the said pocket to act as a load bearing point for lifting using said tethering means.  
           [0014]    It is also an objective of this invention to provide an alternative biasing means and tether means for the auxiliary grip in the form of a reel mechanism to wind up or be pulled out. The said reel mechanism may be formed as part of the shovel scoop, as part of the grip or as part of a unitary shovel embodiment.  
           [0015]    It is also a purpose of this invention to provide the best shoveling action so that the scoop rests upon the ground with the hand grip conveniently grasped by the user standing erect. The opposition of return line retraction force to the force of gravity holding the unburdened weight of the scoop upon the ground must be matched so that the scoop will be held in it&#39;s distal position by gravity upon the blocking means and not hover or bounce elastically from the tension of the biasing means. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0016]    The preceding and other objectives of this invention will be more readily apparent from the following description read in conjunction with the accompanying drawings, in which:  
         [0017]    [0017]FIG. 1 is a perspective view of the invention with grip extended;  
         [0018]    [0018]FIG. 2 is a perspective view of the invention with grip retracted;  
         [0019]    [0019]FIG. 3 is a broken out section side view of the primary handle;  
         [0020]    [0020]FIG. 4 is a perspective view of an anchor;  
         [0021]    [0021]FIG. 5 is a perspective view of tether guide;  
         [0022]    [0022]FIG. 6 is a partial side view section drawing of pocket storing grip;  
         [0023]    [0023]FIG. 7 is a partial top view of a grip and pocket;  
         [0024]    [0024]FIG. 8 is a perspective view of a grip with reel mechanism;  
         [0025]    [0025]FIG. 9 is a partial view of a deposition framework for storing retracted hand grip, and  
         [0026]    [0026]FIG. 10 is a partial section side view taken along line A-A of the framework of FIG. 9. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]    Referring in detail to the drawings, in FIG. 1 the shovel of the present invention includes an elongated primary handle  1 , with one end attached to a shovel scoop  2 , showing the extensible auxiliary grip  3 , extended from its holder. The primary handle  1 , may be formed as a hollow tube or with linear slots or similar means of cavity which will allow free unrestricted motion of the means of return line  40 , towards the anchor point  15 .  
         [0028]    The extensible auxiliary hand grip may be formed as a hollow tube  3 , with the means of tether  4 , entering said hollow tube and looping in a typical “A” shape forming an accessible hand opening and hand hold  5 . The tethering means may be clamped, spliced or connected  6 , in a general “A” shape using any method commonly known to those experienced in the art for fixedly attaching the means of tether. In another form, the connection means  6 , may allow the length of the tethering means to be adjusted by the user as is generally know to those experienced in the art.  
         [0029]    Also in FIG. 1, an egress opening  7 , for said tethering means  4 , may in its simplest form be a circular opening located on the primary handle socket  8 .  
         [0030]    A “D” shaped grip  9 , is located at one end of the elongated primary handle of suitable size to facilitate stability during loading and unloading of the scoop to the side and to act as a fulcrum point when lifting a load using the auxiliary hand grip  3 . Said “D” shaped handle may be formed with a means of anchor  15  as part of the embodiment.  
         [0031]    In FIG. 1 and FIG. 2, a left framing member  10 , and right framing member  11 , may be formed as part of the shovel scoop embodiment  2 , to form a slight cavity which will hold the extensible grip  3 , under the force of the return line as shown in FIG. 2. In the simplest form, said framing members use the retraction force of the biasing means  14 , of FIG. 3, to prevent inertial motion by placing the grip  3 , in mild compression against said framing members which form a notch or friction like keeper. Said framing members may be of increased complexity, shape and configuration as desired.  
         [0032]    In FIG. 9, another form of opposed framing members  10 , and  11 , formed as part of the shovel embodiment or affixed, are shown having an opening on either side  32 , and  33 , where means of tether  4 , extends towards the said egress area  7 , of FIG. 1. The extension of tether  4 , through said openings  32 , and  33 , acts to reduce transverse motion of the hand grip  3 , caused by the inertia in the act of shoveling. In FIG. 10, as viewed through section line A-A of FIG. 9, the general curvature, groove, notch, or slot of said framing member  11 , is shown with an upper elevation or extension  34 , and a lower extension of the framing members  35 . These said extensions may be formed in any way which will generally capture the grip  3 , using the force of said biasing means of the return line for mounting said grip or to almost completely enclosed an auxiliary hand grip  26 , for stowage as in a pocket  25 , of FIG. 7.  
         [0033]    In FIG. 9, a central opening  34 , located between said framing members is for hand access to the grip  3 , outlined with a dashed line.  
         [0034]    [0034]FIG. 3, is another view of primary handle  1 , having a passage  13 , containing a biasing means, such as a helical extension spring  14 , anchored at one end of the handle  15 , and distally attached to the tethering means  4 , as a means of return line using an intermediary connection  16 , of greater dimension than aperture  17 , of means of sheave  18 , as a means of blocking to limit extension of the return line and guiding the said tethering means to an egress  7 , in FIG. 1. Said intermediary connection  16 , may in ifs simplest form be a suitable knot tied in said tether means. Said biasing means  14 , may also be a resilient elastic for warmer climates or of a material with elastic properties not effected by deeper cold  
         [0035]    [0035]FIG. 4, one form of anchor  15 , of FIG. 1, is illustrated as a circular disc  19 , with an arm  20 , as a means of insertion into the terminating helical coil or intermediary connector of said biasing means. Slots  21 , on both sides of arm  20 , may extend past the centre of the disc  19 , to centrally locate a biasing means. The diameter of disc  19 , is greater than that of the primary handle passage  13 , of FIG. 3, but less than the inside diameter of “D” handle socket  36 , of FIG. 2. Said anchor may be any means commonly known to those experienced in the art including a hole in any part of the shovel embodiment distal from said egress.  
         [0036]    Said means of sheave  18 , of FIG. 5, may be formed in any shape  22 , for insertion into said primary handle  1 , of FIG. 3. A step of larger dimension  23 , is required for controlling the depth of insertion into the said primary handle. Said means of sheave  18 , may be constructed to be located in any part of the shovel with steps and cut out sections or as part of the primary handle embodiment in any way commonly known to those experienced in the art for redirecting a tether at diverging angles from an anchor point with minimum friction An arc or curvature  24 , also shown in FIG. 6, is provided for dispensing the tethering means  4 , towards the grip  26 , for extraction and retraction of the extensible hand grip  26 , of FIG. 6, in a way suitable to act as a low friction pulley or sheave in guiding the tether from the primary handle  1 , to the egress  7 , on the shovel scoop  2 , of FIG. 1.  
         [0037]    Means of sheave  18 , may be shaped to fit proximal to any elements of the embodiment of said primary handle  1 , or socket  8 , of FIG. 1. Said means of sheave my contain rotatable axles or other elements as required to guide the string means  4 , as commonly known by those experienced in the art  
         [0038]    [0038]FIG. 6, shows another form of the present invention having a partly enclosed pocket  25 , formed as part of the shovel scoop embodiment for deposition or stowing another form of hand grip  26 , shown in FIG. 7. The extensible tether  4 , when extended, may in certain orientations, contact the inside pocket surface on the curvature  27 , which is formed and reinforced to act as a sheave or guide but mostly as a load bearing support for the force of the means of tether  4 , to act in opposition to the force of the load of burden held in the shovel scoop  2 . The egress point  7 , of FIG. 6, may also be enlarged to act as a fluid or debris drain into the handle socket  8 , cavity where it may be further drained using a second opening  29 .  
         [0039]    Hand grip  26 , embodiment material may be elastomeric or rigid of any thickness or form having a channel  35 , of FIG. 6, where tethering means  4 , may enclose in an “A” shape and provide strength to the auxiliary hand grip  26 . Said pocket may be formed in any way as to mimic the form of said hand grip for the best combination of properties for storage and ease of access.  
         [0040]    In another form of the present invention shown in FIG. 8, the said tethering means and said biasing means have been removed from the handle and placed inside a hand grip  30 . The hand grip  30 , may be constructed in any form which could be stored securely on the embodiment of the shovel for easy access. The general circular shape of the embodiment  28  must be suitable for spooling the return line  40 , through an egress  31 , within a reel for winding up or winding out using any suitable channel  27 , interposed of a return line located within the said grip  30 , using any method commonly known to those experienced in the art.  
         [0041]    It will be understood from the preceding description that a return line including a biasing means, and tethering means, or other intermediary components in combination with a grip and holder, could be placed at any point on the shovel, not necessarily in the primary handle  1 , of FIG. 3, but also within the scoop  2 .  
         [0042]    It will also be understood that the preceding description of the preferred embodiments of the present invention is for the purposes of illustration only and that the various structural and operational features herein described are susceptible to modifications none of which entails departure from the scope and spirit of the present invention herein disclosed

Summary:
This invention describes an extensible grip having a return line to facilitate the extending and retracting of a tethered grip of an ergonomic shovel in accordance with prior art for stand-up shovels using a flexible tether and biasing means. A pocket or frame structure is described for disposition of the retracted auxiliary grip to facilitate storage.