Patent ID: 8534168

Claim:
A pliers for gripping a work piece comprising: an elongated body; an upper jaw at a front of the body; a lower jaw pivotally attached to the body at a pivot pin; a handle linked to the lower jaw wherein moving the handle in relation to the body causes the lower jaw to pivot in relation to the upper jaw; an over-center linkage pivotally attached between the handle and the body to lock the lower jaw against the upper jaw with a gripping force in a loaded condition of the pliers; a pivot pin attached to the lower jaw; a slot in the body; the pivot pin movable between a first and a second location of the body within the slot, the first and second locations of the body corresponding to respective recesses of the slot, a first recess corresponding to a small jaw size range and a second recess corresponding to a large jaw size range, the recesses being in a front side of the slot; the over-center linkage presses the lower jaw forward, and the pivot pin into a selected recess, with a force that is proportionate to the gripping force in the loaded condition; a spring element biasing a first force application location of the lower jaw; a spring link of a spring assembly extending from a second force application location of the lower jaw near the pivot pin, the spring link connected within the spring element whereby the spring link presses the lower jaw forward at the second force application location of the jaw, the spring link and spring element forming a spring assembly; the first force application location is substantially further from the pivot pin than the second force application location is from the pivot pin whereby the lower jaw is firmly biased by the spring assembly to pivot away from the upper jaw in an unloaded condition of the pliers; and, the pivot pin biased into a selected recess in the unloaded condition of the pliers by a force from the spring element through the spring link, the pivot pin being stable within any selected operative recess whereby the selected size range is maintained in the unloaded condition as the handle is moved.