Abstract:
A hammer has a claw assembly that is linearly moveable relative to the head of the hammer so as to improve leverage and range of prying for nail removal. A locking mechanism secures the claw assembly in a position. The locking mechanism may be automatic or manual, and may comprise a ratcheting mechanism with a pawl and rack, or a clamping mechanism with a deflectable sleeve and engaged bar, or a biased pin lock mechanism.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to claw hammers, and, more particularly to a claw hammer with a claw that is moveable relative to the head of the hammer so as to improve leverage and range of prying for nail removal. 
       BACKGROUND 
       [0002]    As is well known, a conventional claw hammer is a tool primarily used for pounding nails into or extracting nails from some other object. Generally, a claw hammer is associated with woodworking but is not limited to use with wood products. 
         [0003]    A conventional claw hammer  10  is illustrated in  FIG. 1 . From a profile, it roughly resembles the letter “T”. The handle  15  is the long vertical part. The head assembly  20  includes a striking head  25  and a curved two-prong claw  30  opposite the striking head. The claw  30  curves downward (i.e., towards the handle) and splits in the middle forming a “V” shape gap  35 . The claw increases in thickness from the free end to the intersection with the handle  15 . This gap  35  is the part of the claw  30  of the hammer  10  that is commonly used for extracting nails from wood. The curved claw  30  in conjunction with the handle  15  is used to gain leverage when extracting a nail. 
         [0004]    The curvature and length of the claw  30  varies among hammers. By way of example, the claw of a framing hammer may feature less curvature than the claw curvature of a finishing hammer and therefore does not have as much leverage for removing nails. While claws are useful for fully extracting short nails in one fluid motion, long nails pose challenges. A claw may not have sufficient length and range of motion to fully extract the nail. The claw may be adequate to partially remove the nail. A user must then struggle to extract the remaining embedded portion of the nail, such as by applying another tool, e.g., pliers, and considerable pulling force or by applying a board, such as a 2×4, to raise the height of the fulcrum point. Although a hammer could be provided with an extremely long curved claw sufficient to extract even the longest nail, such a hammer would be extremely cumbersome to wield. 
         [0005]    The invention is directed to overcoming one or more of the problems and solving one or more of the needs as set forth above. 
       SUMMARY OF THE INVENTION 
       [0006]    To solve one or more of the problems set forth above, in an exemplary implementation of the invention, a hammer includes a linearly adjustable ratcheting claw. The claw assembly includes a claw with a v-shaped groove for engaging a nail. The claw assembly is movable linearly relative to the striking head of the hammer. A channel is configured to receive and glide along an engaging portion of the handle. A locking mechanism secures the claw assembly in a raised or lowered position. In one embodiment, the locking mechanism is a ratcheting mechanism with a pawl that controllably engages and disengages a rack of spaced apart teeth. The pawl and rack regulate linear movement of the claw assembly. A spring compartment in the handle contains a compression spring that urges the claw assembly towards its topmost (extended) position. A nail head lever is attached to the concave side of the claw. The lever extends outwardly from the handle to a point past the vertex of the v-groove. During extraction of a nail using the claw, the head of the nail may bear against the lever. The lever may be attached with a pivot pin and biased to pivot towards an abutting nail head. The lever may also be operably coupled to a linkage coupled to a pawl. The linkage may advance the pawl to allow retraction of the claw assembly when the lever is pushed by a nail. While the pawl locks the claw assembly in place, a permanent magnet at the apex of the handle helps to secure the claw assembly. 
         [0007]    In another embodiment, the locking mechanism is a clamp, such as a spring clamp. The spring clamp includes a sleeve biased to a skewed configuration in relation to a bar. The biasing causes the sleeve to frictionally engage the bar. The bar may be textured or a toothed rack to enhance locking engagement. A control arm coupled to the sleeve allows deflection and alignment of the sleeve to permit sliding motion of the sleeve relative to the bar. The sleeve is pivotally contained within the claw assembly and moves with the claw assembly. The bar is external to the claw assembly and remains stationary. 
         [0008]    In another embodiment, the locking mechanism is a locking pin. The pin is biased towards a bar with a plurality of spaced apart holes, each defining a locking position. A free end of the pin extends through one of a plurality of the holes in the bar, when aligned with a hole. A biasing mechanism allows deflection of the pin away from the bar and out of the hole to permit free sliding motion of the claw assembly. The pin and biasing mechanism are parts of and move with the claw assembly. The bar with holes is external to the claw assembly and remains stationary. 
         [0009]    Regardless of the particular locking mechanism used, a hammer according to principles of the invention includes a claw assembly that can be moved in linear sliding fashion from a fully raised position in general alignment with the hammer head to a fully lowered position between the hammer head and handle. The locking mechanism may be manual or automatic. The locking mechanism secures the claw assembly in a desired position relative to the hammer head. 
         [0010]    An exemplary hammer with a linearly moveable claw assembly according to principles of the invention has a handle, a neck, a hammer head and a claw assembly. The neck of the hammer has a first end and an opposite second end. The neck may be integrally formed with and extending from either or both of the head and handle. The handle is attached to the first end and the hammer head is attached to the second end. The claw assembly includes a claw body from which a curved two-prong claw extends. The claw body contains a guide and a locking mechanism. The guide slidingly engages the neck. The locking mechanism controllably secures (i.e., locks) the claw assembly at a position along the neck. The claw assembly is linearly moveable between the first end and second end of the neck. 
         [0011]    A variety of locking mechanism embodiments are effective. In one embodiment, the locking mechanism is a ratcheting mechanism. The hammer includes a toothed rack attached to the neck, and the ratcheting mechanism includes a pawl pivotally coupled (i.e. coupled in a manner that allows pivoting motion, such as coupling by a pivot pin or hinge) to the claw body and positioned to controllably engage (i.e., in a manner that can be controlled by a user or use) the toothed rack. A lever may be coupled to the pawl. The lever may be pivotally attached to the claw body and pivotally moveable from a released position to an engaged position. In the released position, the pawl may be moveable relative to the rack, and in the engaged position, the pawl may be fixed and engaged by the rack. The lever may be in proximity to the curved two-prong claw, in which case the lever may react to a nail head and be movable to the released position by reaction with the nail head extending through the curved two-prong claw. A spring may bias (i.e., urge) the lever into an engaged position. Such a spring may be contained in the claw body. 
         [0012]    In another embodiment, the locking mechanism is a bar clamp. The hammer may include a bar parallel to the neck and in a fixed position relative to the neck and the locking mechanism may be a bar clamp within the claw body. The bar clamp may be moveable from a released position to an engaged position. In the released position, the bar clamp disengages the bar. In the engaged position the bar clamp frictionally engages the bar and resists movement of the bar clamp relative to the bar. A biasing mechanism may urge the bar clamp into an engaged position. The biasing mechanism may be a spring, such as a leaf spring. The biasing mechanism and bar clamp may be integrally formed. The bar clamp may have an end extending from the claw body. That end may be manipulable by a user (i.e., capable of being maneuvered by a user) to move the bar clamp from an engaged position to a released position. The bar may be textured to enhance frictional engagement. The bar may include a rack with a plurality of spaced apart teeth. The bar clamp may include a bushing (or sleeve) with an aperture sized to receive a portion of the bar. In the engaged position the bushing is skewed angled relative to the bar to frictionally engage the bar, and in the released position the bushing is aligned to the bar to allow movement of the bushing relative to the bar. 
         [0013]    In yet another embodiment, the locking mechanism is a pin lock. The hammer includes a bar parallel to the neck and in a fixed position relative to the neck. The bar has a plurality of spaced apart apertures. The locking mechanism includes a pin with a free end extending from the claw body towards the bar. The pin is moveable from a released position to an engaged position. In the released position the pin disengages the bar. In the engaged position the free end of the pin extends through one of the plurality of spaced apart apertures. A biasing mechanism may urge the pin into an engaged position. The biasing mechanism may be a spring, such as a leaf spring. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The foregoing and other aspects, objects, features and advantages of the invention will become better understood with reference to the following description, appended claims, and accompanying drawings, where: 
           [0015]      FIG. 1  provides profile and perspective views that conceptually illustrate a prior art conventional claw hammer; and 
           [0016]      FIG. 2  provides a perspective view of an exemplary embodiment of a hammer with a linearly adjustable ratcheting claw according to principles of the invention. 
           [0017]      FIG. 3  provides a perspective view of an exemplary embodiment of a portion of a hammer, with the linearly adjustable ratcheting claw removed, according to principles of the invention. 
           [0018]      FIG. 4  provides a perspective view of another exemplary embodiment of a hammer with a linearly adjustable ratcheting claw according to principles of the invention. 
           [0019]      FIG. 5  provides a perspective view of another exemplary embodiment of a hammer with a linearly adjustable ratcheting claw according to principles of the invention. 
           [0020]      FIG. 6  provides a perspective view of an exemplary embodiment of a claw assembly for a hammer with a linearly adjustable ratcheting claw according to principles of the invention. 
           [0021]      FIG. 7  provides a perspective view of another exemplary embodiment of a hammer with a linearly adjustable ratcheting claw according to principles of the invention. 
           [0022]      FIG. 8  provides a perspective view of another exemplary embodiment of a hammer with a linearly adjustable ratcheting claw in a retracted position according to principles of the invention. 
           [0023]      FIG. 9  schematically illustrates an exemplary embodiment of a ratcheting rack and pawl assembly for a hammer with a linearly adjustable ratcheting claw according to principles of the invention. 
           [0024]      FIG. 10  provides a perspective view of another exemplary embodiment of a hammer with a linearly adjustable ratcheting claw in a retracted position according to principles of the invention. 
           [0025]      FIG. 11  provides a perspective view of an exemplary embodiment of a claw assembly for a hammer with a linearly adjustable ratcheting claw according to principles of the invention. 
           [0026]      FIG. 12  provides a side view of another exemplary hammer with a linearly adjustable ratcheting claw in a lowered position according to principles of the invention. 
           [0027]      FIG. 13  provides a perspective view of an exemplary hammer with a linearly adjustable ratcheting claw in a lowered position according to principles of the invention. 
           [0028]      FIG. 14  provides a perspective view of an exemplary claw assembly for a hammer with a linearly adjustable ratcheting claw in a lowered position according to principles of the invention. 
           [0029]      FIG. 15  provides a side view of an exemplary hammer with a linearly adjustable ratcheting claw in a raised position according to principles of the invention. 
           [0030]      FIG. 16  provides a perspective view of an exemplary hammer with a linearly adjustable clamping claw in a raised position according to principles of the invention. 
           [0031]      FIG. 17  provides a perspective view of an exemplary hammer with a linearly adjustable clamping claw in a lowered position according to principles of the invention. 
           [0032]      FIG. 18  provides a perspective view of an exemplary clamping mechanism for a hammer with a linearly adjustable clamping claw according to principles of the invention. 
           [0033]      FIG. 19  provides a perspective view of another exemplary clamping mechanism for a hammer with a linearly adjustable clamping claw according to principles of the invention. 
           [0034]      FIG. 20  provides a side view of an exemplary hammer with a linearly adjustable pin-locking claw in a raised position according to principles of the invention. 
           [0035]      FIG. 21  provides a perspective view of an exemplary hammer with a linearly adjustable pin-locking claw in a raised position according to principles of the invention. 
           [0036]      FIG. 22  provides a side view of an exemplary hammer with a linearly adjustable pin-locking claw in a lowered position according to principles of the invention. 
           [0037]      FIG. 23  provides a perspective view of an exemplary hammer with a linearly adjustable pin-locking claw in a lowered position according to principles of the invention. 
       
    
    
       [0038]    Those skilled in the art will appreciate that the figures are not intended to be drawn to any particular scale; nor are the figures intended to illustrate every embodiment of the invention. The invention is not limited to the exemplary embodiments depicted in the figures or the specific components, configurations, shapes, relative sizes, ornamental aspects or proportions as shown in the figures. 
       DETAILED DESCRIPTION 
       [0039]    Referring now to  FIG. 2 , a perspective view of an exemplary embodiment of a hammer  100  with a linearly adjustable ratcheting claw assembly  160  according to principles of the invention is shown. The claw assembly  160  includes a claw  150  with a v-shaped groove  155  for engaging a nail. The claw assembly  160  is movable linearly relative to the striking head  105  of the hammer. A channel  141  is configured to receive and glide along an engaging portion of the handle. A ratcheting mechanism, which includes a manual switch  140 , causes a pawl to engage and disengage a rack  125  of spaced apart teeth. The pawl and rack regulate linear movement of the claw assembly  160 . 
         [0040]    A spring compartment  130  in the handle  110  contains a compression spring  131  that urges the claw assembly towards its topmost position, as shown in  FIG. 2 . The spring may be a coil, leaf or other type of biasing means that resists compression. A removable cover  135  closes the opening of the spring compartment  130 . The cover  135  fits flush against the opening so as to avoid interference with up and down motion of the claw assembly  160 . 
         [0041]    A nail head lever  145  is attached to the concave side of the claw  150 . The lever  145  extends outwardly from the handle to a point past the vertex of the v-groove. During extraction of a nail using the claw  150 , the head of the nail may bear against the lever  145 . The lever  145  may be attached with a pivot pin and biased to pivot towards an abutting nail head. The lever  145  may also be operably coupled to a linkage coupled to a pawl. The linkage may advance the pawl to allow retraction of the claw assembly  160  when the lever  145  is pivoted by an advancing nail. 
         [0042]    A permanent magnet  165  is attached at the apex of the handle  110 . The magnet  165  is stationary. The claw assembly  160  is comprised of a material to which the magnet  165  is magnetically attracted (e.g., a ferrous material). When the claw assembly  160  is in the fully raised (i.e., topmost) position as shown in  FIG. 2 , the magnet  165  helps securely hold the claw assembly  160 . Rattling, jostling and unintended movement of the claw assembly  160  are alleviated by the magnet  165 . 
         [0043]      FIG. 3  provides a perspective view of an exemplary embodiment of a handle and striking portion of a hammer  100 , with the linearly adjustable ratcheting claw removed, according to principles of the invention. The claw assembly abuts side  120  and is movable linearly relative to the striking head  105  of the hammer. Channels  115  are provided to receive flanged ends (i.e., rails) of a channel of the claw assembly, which glides along an engaging portion of the handle. A rack  125  of spaced apart teeth for the ratcheting action. Notice that the rack is positioned differently than in the embodiment of  FIG. 2 . The particular location of the rack is not important so long as it enables ratcheting control of linear movement of the claw assembly. 
         [0044]    A spring compartment  130  in the handle  110  contains a compression spring  131  that urges the claw assembly towards its topmost position, as discussed above in relation to  FIG. 2 . The spring may be a coil, leaf or other type of biasing means that resists compression. 
         [0045]    Referring now to  FIG. 4 , a perspective view of another exemplary embodiment of a hammer  100  with a linearly adjustable ratcheting claw assembly  160  according to principles of the invention is shown. As with the embodiment described above, the claw assembly  160  includes a claw  150  with a v-shaped groove  155  for engaging a nail. The claw assembly  160  is movable linearly relative to the striking head  105  of the hammer. A channel of the claw assembly with flanged ends is configured to receive and glide along an engaging portion of the handle. The flanged ends slide within channels  132  in the handle  110 . A ratcheting mechanism, which includes a manual switch  140  and a cantilevered support  142 , causes a pawl to engage and disengage a rack of spaced apart teeth. The pawl and rack regulate linear movement of the claw assembly  160 . 
         [0046]    A spring compartment  130  in the handle  110  contains a compression spring  131  that urges the claw assembly towards its topmost position, as shown in  FIG. 4 . The spring may be a coil, leaf or other type of biasing means that resists compression. 
         [0047]    A nail head lever  145  is attached to the concave side of the claw  150 . The lever  145  extends outwardly from the handle to a point past the vertex of the v-groove. During extraction of a nail using the claw  150 , the head of the nail  152  may bear against the lever  145 . The lever  145  may be attached with a pivot pin and biased to pivot towards the abutting nail head. The lever  145  may also be operably coupled to a linkage coupled to a pawl. The linkage may advance the pawl to allow retraction of the claw assembly  160  when the lever  145  is pivoted by an advancing nail. 
         [0048]    A permanent magnet  165  is attached at the apex of the handle  110 . The magnet  165  is stationary. The claw assembly  160  is comprised of a material to which the magnet  165  is magnetically attracted (e.g., a ferrous material). When the claw assembly  160  is in the fully raised (i.e., topmost) position as shown in  FIG. 4 , the magnet  165  helps securely hold the claw assembly  160 . Rattling, jostling and unintended movement of the claw assembly  160  are alleviated by the magnet  165 . 
         [0049]      FIG. 5  provides a perspective view of another exemplary embodiment of a hammer  100  with a linearly adjustable ratcheting claw assembly  160  according to principles of the invention. Certain portions of the hammer are shown transparent, to conceptually illustrate components that would otherwise be hidden by the solid structures. The claw assembly  160  includes a claw  150  with a v-shaped groove  155  for engaging a nail  152 . The claw assembly  160  is movable linearly relative to the striking head  105  of the hammer. A flanged channel is configured to engage and glide in channels  132  along an engaging portion of the handle. A ratcheting mechanism which includes a manual switch  140  (e.g., lever or slide) that causes a pawl to engage and disengage a rack of spaced apart teeth. The pawl and rack regulate linear movement of the claw assembly  160 . 
         [0050]    A spring compartment  130  in the handle  110  contains a compression spring  131  that urges the claw assembly towards its topmost position, as shown in  FIG. 2 . The spring may be a coil, leaf or other type of biasing means that resists compression. A removable cover  135  closes the opening of the spring compartment  130 . The cover  135  fits flush against the opening so as to avoid interference with up and down motion of the claw assembly  160 . 
         [0051]    A nail head lever  145  is attached to the concave side of the claw  150 . The lever  145  extends outwardly from the handle to a point past the vertex of the v-groove. During extraction of a nail using the claw  150 , the head of the nail may bear against the lever  145 . The lever  145  may be attached with a pivot pin  146  and biased to pivot towards an abutting nail head. The lever  145  may also be operably coupled to a guide rail  147  by guide pins  148 . Pivoting movement of the lever  145  may engage and release the pawl to allow locking and retraction of the claw assembly  160 . 
         [0052]    A permanent magnet  165  is attached at the apex of the handle  110 . The magnet  165  is stationary. The claw assembly  160  is comprised of a material to which the magnet  165  is magnetically attracted (e.g., a ferrous material). When the claw assembly  160  is in the fully raised (i.e., topmost) position as shown in  FIG. 2 , the magnet  165  helps securely hold the claw assembly  160 . Rattling, jostling and unintended movement of the claw assembly  160  are alleviated by the magnet  165 . 
         [0053]      FIG. 6  provides a perspective view of an exemplary embodiment of a claw assembly  160  for a hammer with a linearly adjustable ratcheting claw according to principles of the invention. The claw assembly  160  includes a claw  150  with a v-shaped groove  155  for engaging a nail  152 . The claw assembly  160  is movable linearly relative to the striking head  105  of the hammer. Flanged channels  162 ,  164  are configured to engage and glide in channels along an engaging portion of a handle. A ratcheting mechanism which includes a manual switch  140  that causes a pawl  147  to engage and disengage a rack of spaced apart teeth. The pawl  147  and rack regulate linear movement of the claw assembly  160 . 
         [0054]    A nail head lever  145  is attached to the concave side of the claw  150 . The lever  145  extends outwardly from the handle to a point past the vertex of the v-groove. During extraction of a nail using the claw  150 , the head of the nail may bear against the lever  145 . The lever  145  may be attached with a pivot pin  146  and biased to pivot towards an abutting nail head. The lever  145  may also be operably pivotally coupled to a second lever  149  configured to pivot in a direction opposite to the pivoting direction of the primary lever  145 . The secondary lever  149  may be spring biased, such as with a torsion spring. Pivoting movement of the primary lever  145  may engage and release the pawl to allow locking and retraction of the claw assembly  160 . 
         [0055]      FIG. 7  provides a perspective view of another exemplary embodiment of a hammer with a linearly adjustable ratcheting claw according to principles of the invention. The claw assembly  160  includes a claw  150  with a v-shaped groove  155  for engaging a nail  152 . The claw assembly  160  is movable linearly relative to the striking head  105  of the hammer. A flanged channel is configured to engage and glide in channels  148  along an engaging portion of the handle. A ratcheting mechanism causes a pawl  173  to engage and disengage a rack  125  of spaced apart teeth. The pawl  173  and rack  125  regulate linear movement of the claw assembly  160 . 
         [0056]    A spring compartment  130  in the handle  110  contains a compression spring  131  that urges the claw assembly towards its topmost position, as shown in  FIG. 7 . The spring  131  may be a coil, leaf or other type of biasing means that resists compression. A removable cover  131  closes the opening of the spring compartment  130 . The cover  131  fits flush against the opening so as to avoid interference with up and down motion of the claw assembly  160 . 
         [0057]    A nail head lever  145  is attached to the concave side of the claw  150 . The lever  145  extends outwardly from the handle to a point past the vertex of the v-groove. During extraction of a nail using the claw  150 , the head of the nail may bear against the lever  145 . The lever  145  may be attached with a pivot pin  146  and magnetically biased to pivot to a locking position. A magnet  172  is provided to urge the lever and pawl into a locking position. Pivoting movement of the lever  145  may engage and release the pawl  173  to allow locking and retraction of the claw assembly  160 . 
         [0058]      FIG. 8  provides a perspective view of another exemplary embodiment of a hammer  100  with a linearly adjustable ratcheting claw assembly  160  in a retracted position according to principles of the invention. The hammer  100  is substantially the same as the embodiment in  FIG. 2 . The claw assembly  160  is shown moved linearly relative to the striking head  105  of the hammer to an extracting position. The distance between the fulcrum at the magnet  165  and the engaged nail  152  has been substantially increased. This distance provides increased leverage and range of motion to extract a nail  152 . After the nail is extracted, the pawl may be released (i.e., disengaged from the rack) and the claw assembly may be returned to its fully extended position as shown in  FIG. 2 . 
         [0059]      FIG. 9  schematically illustrates an exemplary embodiment of a ratcheting rack  200  and pawl  215  assembly for a hammer with a linearly adjustable ratcheting claw according to principles of the invention. The ratchet allows continuous linear motion in only one direction (i.e., the retracting direction) while preventing motion in the opposite direction (the extended direction), until a pawl  215  is released. The ratchet includes a linear rack  200  with teeth  205 , and a pivoting, springloaded finger called a pawl  215  that engages the teeth. The teeth  205  are uniform but asymmetrical, with each tooth having a moderate slope on one edge and a much steeper slope on the other edge. When the pawl is moving in the unrestricted (i.e., retracting) direction, the pawl  215  easily slides up and over the gently sloped edges of the teeth, with a spring forcing it (possibly with an audible “click”) into the depression  210  between the teeth as it passes the tip of each tooth. When the pawl  215  moves in the opposite (backward) direction, however, the pawl will catch against the steeply sloped edge of the first tooth it encounters, thereby locking it against the tooth and preventing any further motion in that direction. The pawl&#39;s range of rotation is controllably restricted to ensure catching until released, while allowing pivoting for retracting linear movement. By way of example and not limitation a stop  240  may prevent rotation of the pawl in one direction  235 , until the stop is moved, while permitting substantial rotation in the opposite direction  230 . In one embodiment, the pawl  215  is coupled to a lever  220  acted upon, directly or indirectly, by the head of a nail. The head of a nail pushing against the lever  220  causes the pawl  215  to move in the retracting direction along the rack  200 . 
         [0060]      FIG. 10  provides a perspective view of another exemplary embodiment of a hammer with a linearly adjustable ratcheting claw according to principles of the invention. The claw assembly  160  includes a claw  150  with a v-shaped groove  155  for engaging a nail  152 . The claw assembly  160  is movable linearly relative to the striking head  105  of the hammer. A flanged channel is configured to engage and glide in channels  148  along an engaging portion of the handle. A ratcheting mechanism with a pivoting lever  180 , a ratchet body and a ratchet switch  184  causes a pawl to engage and disengage a rack  125  of spaced apart teeth. The pawl and rack  125  regulate linear movement of the claw assembly  160 . The switch  184  affects the angle of the pawl relative to the engaged teeth of the rack  125  to allow or resist movement in one direction or another. Thus, in this embodiment, movement in each direction (i.e., up/down) is controlled by ratcheting. 
         [0061]    Alternatively, the switch  184  may have an engaged position and a free position. In the engaged position, the ratchet causes the claw assembly to move linearly away from the striking head  105  of the hammer. In the free position, the pawl is disengaged and the claw assembly may be slid linearly in either direction. 
         [0062]    A nail head lever  145  is attached to the concave side of the claw  150 . The lever  145  extends outwardly from the handle to a point past the vertex of the v-groove. During extraction of a nail using the claw  150 , the head of the nail may bear against the lever  145 . The lever  145  may be attached with a pivot pin  146  and magnetically biased to pivot to a locking position. A magnet  172  is provided to urge the lever and pawl into a locking position. Pivoting movement of the lever  145  may engage and release the pawl  173  to allow locking and retraction of the claw assembly  160 . 
         [0063]      FIG. 11  provides a perspective view of an exemplary embodiment of a claw assembly  160  for a hammer with a linearly adjustable ratcheting claw according to principles of the invention. The claw assembly  160  includes a claw  150  with a v-shaped groove  155  for engaging a nail  152 . The claw assembly  160  is movable linearly relative to the striking head  105  of the hammer. Flanged channels  162 ,  164  are configured to engage and glide in channels along an engaging portion of a handle. A ratcheting mechanism which includes a manual switch  140  that causes a pawl  147  to engage and disengage a rack of spaced apart teeth. The pawl  147  and rack regulate linear movement of the claw assembly  160 . 
         [0064]    A nail head lever  145  is attached to the concave side of the claw  150 . The lever  145  extends outwardly from the handle to a point past the vertex of the v-groove. During extraction of a nail using the claw  150 , the head of the nail may bear against the lever  145 . The lever  145  may be attached with a pivot pin  146  and biased to pivot towards an abutting nail head. The lever  145  may also be operably pivotally coupled to a second lever  149  configured to pivot in a direction opposite to the pivoting direction of the primary lever  145 . The secondary lever  149  may be spring biased, such as with a torsion spring. Pivoting movement of the primary lever  145  may engage and release the pawl to allow locking and retraction of the claw assembly  160 . 
         [0065]    A spring compartment  130  in the handle  110  contains a compression spring  131  that urges the claw assembly towards its topmost position, as discussed above in relation to  FIG. 2 . The spring may be a coil, leaf or other type of biasing means that resists compression. 
         [0066]      FIGS. 12 through 15  conceptually illustrate another exemplary embodiment of a hammer with a linearly adjustable ratcheting claw. The hammer includes a handle  110  and stationary hammer head  105 . A cap  300  provides a pivot point for removing a nail with the claw assembly  310 . A biased pivoting pawl  330 , projects through an aperture  332  [ FIG. 14 ] to engage a toothed rack  305 . A channel  325  in the claw assembly  310  provides a conduit for linear sliding motion relative to the rack  305  with a portion of the rack  305  being disposed in the channel  325 . Flanges  337  which grip tracks  320  prevent separation of the claw assembly from the hammer head  105 , while permitting linear motion. A lever  317  and pawl pivot point  315  allow manually control of the pawl. When the lever is pressed the tip of the pawl  330  is urged away from the rack  305 . When the lever is released, the pawl engages the rack  305 . The channel body  335  recedes into a cavity in the handle  110  as the claw is lowered, providing additional stability for the claw assembly  310 . The hammer head is supported by a stationary arm  338 . 
         [0067]      FIGS. 16 through 19  illustrate another exemplary embodiment. Instead of a ratcheting mechanism for locking the claw assembly  310  in a position, a clamping mechanism is provided. The clamping mechanism includes a bushing or sleeve  345  (referred to herein as a sleeve) with an aperture  365  through which a bar  340  extends. When released, the sleeve  345  is biased into a skewed position relative to the bar  340 , frictionally engaging the bar  340 . When pressed manually, the sleeve is urged into alignment with the bar  340 , allowing sliding motion of the sleeve  345  with the claw assembly  310 . The bar  340  remains stationary. In the exemplary embodiment, the sleeve  345  is an L-shaped, U-Shaped or V-shaped leaf spring, with a portion attached  350  to the interior  355  of the claw assembly  310 . The attached portion biases the portion with the aperture  365  into a skewed clamping alignment relative to the bar  340 . The portion with the aperture  365  may be urged into alignment relative to the bar  340  to allow free sliding motion of the claw assembly  310  relative to the hammer head  105 . When the portion with the aperture  365  is released, the biasing deflects the aperture  365  back into a skewed clamping alignment relative to the bar  340 . An edge  370  of the bar may be smooth, textured to enhance frictional engagement with the sleeve  345 , or toothed  375  to define specific engagement points between teeth. A flanged channel  350  is provided to guide linear motion of the claw assembly relative to the hammer head  105 . 
         [0068]      FIGS. 20 through 22  conceptually illustrate an exemplary hammer with a linearly adjustable pin-locking claw according to principles of the invention. A pin with a head  415  and shaft  417  is biased towards a bar  400  with a plurality of spaced apart apertures  405 . A portion of the shaft  417  extends through or into an aperture  405  when the pin is aligned with aperture  405  and released. In the exemplary embodiment, a leaf spring  410  attached at one end  412  to the claw assembly provides the biasing. The head  415  of the pin is moved away from the bar  400  by deflecting the leaf spring  410  accordingly. Movement of the head  415  away from the bar causes the pin to move out of the aperture  405 . Such movement permits free sliding motion of the claw assembly  310  relative to the hammer head  105 . 
         [0069]    While an exemplary embodiment of the invention has been described, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. With respect to the above description then, it is to be realized that the optimum relationships for the components and steps of the invention, including variations in order, form, content, function and manner of operation, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. The above description and drawings are illustrative of modifications that can be made without departing from the present invention, the scope of which is to be limited only by the following claims. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents are intended to fall within the scope of the invention as claimed.