Rock climbing adjustable chock

Abstract

An adjustable chock having a biforcated handle (20) with a shaft (30) tensionally positioned between the forks in closed loop fashion. Three opposed cams (34) with teeth on the periphery are positioned on the shaft (30) and spring loaded to rotate to their widest point of separation. A pull rod (40) is slideably located within a slot (28) in each fork of the handle (20) with a connecting link (42) pivotally attached on one end to the link and on the other to the cam (34). When the pull rod (40) is manually retracted, the cams (34) are rotated to their minimum width for insertion into a rock fissure and when released spring loadingly return to the open position for gripping the internal surface in a chock like manner.

I claim: 
     
       1. A rock climbing adjustable chock of the type having opposed pivotal cams the improvement comprising: (a) a biforcated yoke handle haivng a counter-bored hole in each fork on the first end and a palm shaped second end with opposed extending fingers, each fork having a slot in parallel planar relationship;   (b) a shaft tensionally positioned between said forks of the handle, each end urgingly supported within said counterbored holes;   (c) a plurality of opposed cams rotatably positioned on said shaft at least one pivoting in one direction and at least a pair pivoting in the opposite direction, for gripping the inside surface of a crack in a rock;   (d) a plurality of torsional springs disposed upon said shaft with each end pivotally fixed to said cam urging opposed rotation thereof;   (e) a pull rod slideably disposed within said slot in each fork free to move transversely fore and aft, providing a gripping surface for actuation of said chock; and,   (f) a plurality of connecting links, each link freely reciprocable having one end pivotally mounted on the periphery of said cam and the other end slideably joined to said pull rod for retractably rotating said spring loaded opposed cams when sliding said pull rod toward said palm shaped yoke end while being inserted into an open rock fault, further providing an adjustable device to which a climbing rope may be attached to arrest a fall.   
     
     
       2. The apparatus as recited in claim 1 further comprising: said yoke handle having an attaching cavity therethrough disposed within said palm shaped second end providing a mounting location for a rock climbing rope to be joined thereupon. 
     
     
       3. The apparatus as recited in claim 1 wherein said shaft is permanently fastened to siad handle with an expansion rivet in each end positioned within said counterbored holes. 
     
     
       4. The apparatus as recited in claim 1 wherein said opposed cams further comprise; a plurality of teeth on the outside edge in spaced relationship for gripping onto the interstice of a crack in a rock. 
     
     
       5. The apparatus as recited in claim 4 further comprising; a stop extending from the surface of said cam in such a location as to matingly abut with each other when rotated at a full open position providing a stop therebetween. 
     
     
       6. The invention as recited in claim 5 wherein said stop further comprises; a roll pin pressed into said cam flush with one side and extending outwardly on the other in contiguous relationship with said cams positioned on said shaft. 
     
     
       7. The apparatus as recited in claim 1 further comprising a locking ring retained within a groove on said pull rod on each end proximal to said slot in the forks slideably contiguous with the outside surface for retaining the rod within the slot while allowing movement therewithin. .Iadd. 
     
     
       8.  A rock climbing adjustable chock of the type having opposed pivotal cams the improvement comprising: (a) a bifurcated yoke handle having a hole in each fork on the first end and a second end;   (b) a shaft tensionally positioned between said forks of the handle, each end urgingly supported within said holes;   (c) a plurality of opposed cams rotatably positioned on said shaft, at least one pivoting in one direction and at least a pair pivoting in the opposite direction, for gripping the inside surface of a crack in a rock;   (d) a plurality of torsional springs disposed upon said shaft with each end pivotally fixed to said cam urging opposed rotation thereof;   (e) a pull rod slideably disposed relative to each fork and free to move transversely fore and aft, providing a gripping surface for actuation of said chock; and;   (f) a plurality of connecting links, each link freely reciprocable having one end pivotally mounted on the periphery of said cam and the other end slidably joined to said pull rod for retractably rotating said spring loaded opposed cams when sliding said pull rod toward said second yoke end while being inserted into an open rock fault, further providing an adjustable device to which a climbing rope may be attached to arrest a fall. .Iaddend. .Iadd.9. The apparatus as recited in claim 8 wherein said yoke handle has an attaching cavity therethrough disposed within said second end providing a mounting location for a rock climbing rope to be joined thereupon. .Iaddend. .Iadd.10. The apparatus as recited in claim 8 wherein said shaft is permanently fastened to said handle with an expansion rivet in each end positioned within said holes. .Iaddend.   
     
     
        .Iadd. 1.  The apparatus as recited in claim 8 wherein said opposed cams further have a plurality of teeth on the outside edge in spaced relationship for gripping onto the interstice of a crack in a rock. .Iaddend. .Iadd.12. The apparatus as recited in claim 11 further comprising; a stop extending from the surface of said cam in such a location as to matingly abut with each other when rotated at a full open position providing a stop therebetween. .Iaddend. .Iadd.13. The invention as recited in claim 12 wherein said stop further comprises: a roll pin for each said cam flush with one side and extending outwardly on the other in contiguous relationship with said cams positioned on said shaft. .Iaddend. .Iadd.14. The apparatus as recited in claim 8 further comprising a locking means on said pull rod on each end slidably contiguous with the outside surface of the forks for retaining the rod on said forks while allowing movement therewithin. .Iaddend.