Dulling prevention for sharp cutting edge of blade-opening arrowhead blades when in a closed in-flight position II

Abstract

Blade-opening arrowheads with removably attachable pivotal blades, each having an edge with at least a section thereof that is sharpened for cutting. The sharp cutting edges are prevented from being dulled from contact with their corresponding arrowhead bodies, arrowhead tips or other structure when the blades are folded into a retracted in-flight position or into a closed position by means that prevent the sharp cutting edge(s) from contacting against a substance.

I claim:  
     
         1 . A blade-opening arrowhead comprising: 
 (a) an arrowhead body having a central longitudinal axis;    (b) a blade having a first end, an opposing second end and an edge extending thereabout, said edge having a sharpened cutting edge;    (c) hinge means for pivotally connecting said second end of said blade to said arrowhead body to enable said blade to rotate between a retracted position wherein said blade is positioned adjacent to said arrowhead body and an open position wherein said first end of said blade is rotated away from said arrowhead body; and    (d) hover means for preventing said cutting edge from abutting into a substance when said blade is in said retracted position.    
     
     
         2 . A blade-opening arrowhead as recited in  claim 1  wherein said hinge means is displaced a distance from said central longitudinal axis of said arrowhead body so as to not intersect said longitudinal axis thereof.  
     
     
         3 . A blade-opening arrowhead as recited in  claim 1  wherein a substantial portion of said inner cutting edge is substantially straight.  
     
     
         4 . A blade-opening arrowhead as recited in  claim 1  wherein said blade further comprises an outwardly projecting wing located at said first end of said blade, at least a section of said wing being exposed a distance outward from said arrowhead body when said blade is in said retracted position.  
     
     
         5 . A blade-opening arrowhead as recited in  claim 1  wherein said inner cutting edge of said blade is folded adjacent to said arrowhead body when in said retracted position so as to be closer to a central longitudinal axis of said arrowhead body than an outer blunt edge of said blade is from said longitudinal axis.  
     
     
         6 . A blade-opening arrowhead as recited in  claim 1  wherein said blade further comprises a notch formed thereon.  
     
     
         7 . A blade-opening arrowhead as recited in  claim 6  wherein said notch is disposed near said first end of said blade.  
     
     
         8 . A blade-opening arrowhead as recited in  claim 7  wherein said first end of said blade engages with said arrowhead body or with an attached arrowhead tip.  
     
     
         9 . A blade-opening arrowhead as recited in  claim 8  wherein a protrusion extends from said arrowhead body or said arrowhead tip, said notch engaging with said protrusion when the arrowhead is in a retracted configuration.  
     
     
         10 . A blade-opening arrowhead as recited in  claim 6  wherein said notch is disposed near said second end of said blade.  
     
     
         11 . A blade-opening arrowhead as recited in  claim 1  wherein an urging force is applied to said second end of said blade at distance lateral of a cross-sectional center of said hinge means so that said first end of said blade is rotated inwardly when said blade is in said retracted position.  
     
     
         12 . A blade-opening arrowhead as recited in  claim 1  wherein an urging force is applied to said second end of said blade at distance medially of a cross-sectional center of said hinge means so that said first end of said blade is rotated outwardly when said blade is in said retracted position.  
     
     
         13 . A blade-opening arrowhead comprising: 
 (a) an arrowhead body;    (b) a blade having a first end, an opposing second end and an inner sharpened edge, said inner sharpened edge comprising a discrete cutting edge;    (c) hinge means for pivotally connecting said second end of said blade to said arrowhead body to enable said blade to rotate between a retracted position wherein said blade is positioned adjacent to said arrowhead body and an open position wherein said first end of said blade is rotated away from said arrowhead body; and    (d) means for preventing said discrete cutting edge from abutting into a substance when said blade is in said retracted position.    
     
     
         14 . A blade-opening arrowhead as recited in  claim 13  wherein said means for preventing said discrete cutting edge from abutting into a substance comprises: 
 (i) a pair of grind bevels formed on said inner sharpened edge so that said discrete cutting edge is situated therebetween; and  
 (ii) a spacer element having a void for protectedly housing said discrete cutting edge therein so that said discrete cutting edge does not abut into a substance when said blade is in said retracted position, said grind bevels abutting against said spacer element when said blade is in said retracted position.  
 
     
     
         15 . A blade-opening arrowhead as recited in  claim 13  wherein said means for preventing said discrete cutting edge from abutting into a substance comprises an outward rotational force acting upon said blade so as to rotate said first end of said blade in a direction away from said arrowhead body when said blade is in said retracted position.  
     
     
         16 . A blade-opening arrowhead as recited in  claim 13  wherein said means for preventing said discrete cutting edge from abutting into a substance comprises: 
 (i) a rotational limiting element; and  
 (ii) bias means for producing an urging force that is applied to said second end of blade so as to cause said first end of said blade to rotate in a direction when said blade is in said retracted position, said rotational limiting element limiting the distance said blade is rotated by said urging force when in said retracted position so that said sharpened edge is displaced a distance away from said arrowhead body, thereby preventing said cutting edge from abutting into a substance.  
 
     
     
         17 . A blade-opening arrowhead as recited in  claim 16  wherein said blade further comprises a notch, said rotational limiting element being engaged in said notch when said blade is in said retracted position.  
     
     
         18 . A blade-opening arrowhead as recited in  claim 16  wherein said bias means is comprised of an organic polymer.  
     
     
         19 . A blade-opening arrowhead as recited in  claim 13  wherein said hinge means is displaced a distance from a central longitudinal axis of said arrowhead body so as to not intersect said longitudinal axis thereof.  
     
     
         20 . A blade-opening arrowhead as recited in  claim 19  wherein a substantial portion of said inner cutting edge is substantially straight.  
     
     
         21 . A blade-opening arrowhead as recited in  claim 19  wherein said blade further comprises an outwardly projecting wing located at said first end of said blade, at least a section of said wing being exposed a distance outward from said arrowhead body when said blade is in said retracted position.  
     
     
         22 . A blade-opening arrowhead as recited in  claim 13  wherein said inner cutting edge of said blade is folded adjacent to said arrowhead body when in said retracted position so as to be closer to a central longitudinal axis of said arrowhead body than an outer blunt edge of said blade is from said longitudinal axis.  
     
     
         23 . A blade-opening arrowhead comprising; 
 (a) an arrowhead body having a central longitudinal axis;    (b) a blade having a first end, an opposing second end and an edge extending thereabout, said edge having a sharpened cutting edge;    (c) hinge means for pivotally connecting said second end of said blade to said arrowhead body to enable said blade to rotate between a retracted position wherein said blade is positioned adjacent to said arrowhead body and an open position wherein said first end of said blade is rotated away from said arrowhead body, said hinge means having a cross sectional center;    (d) a rotational limiting element for engaging with said second of said blade; and    (e) bias means for producing an urging force to engage said rotational limiting element against said second end of said blade, said urging force being applied to said second end of said blade at a location spaced apart from a plane parallel to said longitudinal axis that intersects said cross sectional center of said hinge means so as to rotate said first end of said blade in a direction when said blade is in said retracted position.    
     
     
         24 . A blade-opening arrowhead as recited in  claim 23  wherein said inner cutting edge of said blade is folded adjacent to said arrowhead body when in said retracted position so as to be closer to a central longitudinal axis of said arrowhead body than an outer blunt edge of said blade is from said longitudinal axis.  
     
     
         25 . A blade-opening arrowhead as recited in  claim 23  wherein said blade further comprises an outwardly projecting wing located at said first end of said blade, at least a section of said wing being exposed a distance outward from said arrowhead body when said blade is in said retracted position.  
     
     
         26 . A blade-opening arrowhead as recited in  claim 23  wherein said urging force is applied to said second end of said blade at distance lateral of said cross-sectional center of said hinge means so that said first end of said blade is rotated inwardly when said blade is in said retracted position.  
     
     
         27 . A blade-opening arrowhead as recited in  claim 23  wherein said urging force is applied to said second end of said blade at distance medially of said cross-sectional center of said hinge means so that said first end of said blade is rotated outwardly when said blade is in said retracted position.  
     
     
         28 . A blade-opening arrowhead as recited in  claim 23  wherein said rotational limiting element comprises holding means for engaging against said edge of said blade so as to selectively hold said blade adjacent to said arrowhead body when said blade is in said retracted position.  
     
     
         29 . A blade-opening arrowhead as recited in  claim 28  wherein said rotational limiting element is annular.  
     
     
         30 . A blade-opening arrowhead as recited in  claim 23  wherein said hinge means is spaced a part a distance from said central longitudinal axis.  
     
     
         31 . A blade-opening arrowhead as recited in  claim 23  further comprising retaining means for selectively retaining said blade is said retracted position and enabling said blade to rotate into said open position when acted upon by an opening force, said retaining means including said rotational limiting element and said bias means.  
     
     
         32 . A blade-opening arrowhead as recited in  claim 23  wherein said bias means comprises a compressible annular spring.  
     
     
         33 . A blade-opening arrowhead as recited in  claim 23  wherein said bias means comprises a compressible rubber ring.  
     
     
         34 . A blade-opening arrowhead as recited in  claim 23  wherein said urging force is applied to said blade at a location spaced apart from said central longitudinal axis of said arrowhead body.  
     
     
         35 . A blade-opening arrowhead as recited in  claim 23  wherein said hinges means is displaced a distance from said central longitudinal axis of said arrowhead body so as not to intersect said longitudinal axis thereof.  
     
     
         36 . A blade-opening arrowhead comprising: 
 (a) an arrowhead body having a central longitudinal axis;    (b) a blade having a first end, an opposing second end and an edge extending thereabout, said edge having a cutting edge and a notch formed therein at said second end of said blade;    (c) hinge means for pivotally connecting said second end of said blade to said arrowhead body to enable said blade to rotate between a retracted position wherein said blade is positioned adjacent to said arrowhead body and an open position wherein said first end of said blade is rotated away from said arrowhead body;    (d) an annular element for engaging within said notch; and    (e) bias means for producing an urging force to engage said annular element into said notch, said urging force being applied to said second end of blade so as to cause said first end of said blade to rotate in a direction when said blade is in said retracted position until said annular element abuts into a side of said notch, thereby controlling the distance between said cutting edge and said arrowhead body.    
     
     
         37 . A blade-opening arrowhead as recited in  claim 36  wherein said urging force is applied to said second end of said blade at a location spaced apart from a plane parallel to said longitudinal axis that intersects said cross sectional center of said hinge means so as to rotate said first end of said blade in a direction when said blade is in said retracted position.  
     
     
         38 . A blade-opening arrowhead as recited in  claim 36  wherein said notch further comprises an inner side, and an outer side.  
     
     
         39 . A blade-opening arrowhead as recited in  claim 38  wherein said urging force is applied to said second end of said blade at distance lateral of said cross-sectional center of said hinge means so that said first end of said blade is rotated inwardly when said blade is in said retracted position until said inner side of said notch abuts against said rotational limiting element, thereby controlling the distance between said cutting edge and said arrowhead body.  
     
     
         40 . A blade-opening arrowhead as recited in  claim 38  wherein said urging force is applied to said second end of said blade at distance medially of said cross-sectional center of said hinge means so that said first end of said blade is rotated outwardly when said blade is in said retracted position until said outer side of said notch abuts against said rotational limiting element, thereby controlling the distance between said sharpened edge and said arrowhead body.  
     
     
         41 . A blade-opening arrowhead as recited in  claim 36  further comprising retaining means for selectively retaining said blade is said retracted position and enabling said blade to rotate into said open position when acted upon by an opening force, said retaining means including said rotational limiting element and said bias means.  
     
     
         42 . A blade-opening arrowhead as recited in  claim 36  wherein said bias means comprises a compressible annular spring.  
     
     
         43 . A blade-opening arrowhead as recited in  claim 36  wherein said inner cutting edge of said blade is folded adjacent to said arrowhead body when in said retracted position so as to be closer to a central longitudinal axis of said arrowhead body than an outer blunt edge of said blade is from said longitudinal axis.  
     
     
         44 . A blade-opening arrowhead as recited in  claim 36  wherein said blade further comprises an outwardly projecting wing located at said first end of said blade, at least a section of said wing being exposed a distance outward from said arrowhead body when said blade is in said retracted position.