Abstract: Pliers with self-adjustment capability for applying a grasping force to a workpiece and for augmenting the grasping force applied to the workpiece which include a first plier member, a second plier member, a first pivot, a second pivot and a first biasing spring. The first plier member includes a handle portion, a jaw portion, an intermediate portion, a coupling interconnecting the handle portion of the first plier member to the intermediate portion of the first plier member, and locking device. The second plier member includes a handle portion, a jaw portion, and an intermediate portion disposed therebetween. The first pivot includes a shifting slot portion, a transitional portion, and a positioning slot portion with a generally arcuate portion formed in said intermediate portion of the first plier member. The first pivot also includes at least one pivot member extending into, and movable within, the shifting slot portion, transitional portion, and positioning slot portion.

Abstract: Self adjusting pliers for grasping a workpiece include first and second plier members each including a handle portion, a jaw portion, and an intermediate portion therebetween. The self-adjusting pliers include a first pivot pin about which the first and second plier members pivot permitting the jaw portions to converge on a workpiece and grasp the workpiece in response to initial movement of the handle portions toward each other. The self adjusting pliers further include a second pivot pin about which the pliers pivot once pivoting has been terminated about the first pivot pin so as to permit a further grasping force to be applied to the workpiece in response to continued movement of the handle portions toward each other. The second pivot pin is closer to the jaw portions than the first pivot pin to allow for a greater mechanical advantage to be obtained. The self adjusting pliers also include a biasing spring for biasing the handle portions away from each other and the jaw portions away from each other.