Lever locking worm adjustable wrench

A lever locking worm adjustable wrench includes a handle terminating in a fixed jaw, a movable jaw slidably received in the handle in opposing relation to the fixed jaw, and rack gear teeth formed on the movable jaw. A worm mounting arm has a worm gear rotatably mounted thereon and is pivotally mounted on the handle to move the worm gear in a direction substantially tangential to the direction of the rack. An operating lever is pivotally connected to the worm mounting arm and is connected by a toggle link to the handle. Upon movement of the lever toward the handle, the movable jaw is moved toward the fixed jaw to grippingly engage a workpiece, such as a nut or bolt head therebetween. The toggle link, operating lever, and handle cooperate to define an over-center locking mechanism whereby the movable jaw is releasably locked in gripping engagement with the workpiece against the fixed jaw.