Open-end ratchet wrench

Abstract

A wrench includes a pair of jaws mounted to a handle. A first jaw is mounted for selective actuation by an actuator between a stationary position with respect to a second jaw so that the jaws engage and rotate the workpiece when the wrench handle is rotated, and a movable position with respect to the second jaw so that the jaws disengage and slide over the workpiece (e.g., in a ratchet-like manner) and allow the workpiece to remain stationary when the handle is rotated. The wrench operates in the selected mode of operation (i.e., driving or ratcheting) when the handle is rotated in either direction. Another wrench (which is not bi-directional) features a pair of plates pivotally mounted within cavities in a pair of spaced jaws on the wrench handle. Each plate includes a grasping surface for engaging a face of the workpiece and a curved peripheral surface which slidingly engages a curved bearing surface in the cavity so that the plate can pivot within the cavity. A spring biases the plates toward each other so that the plates engage the workpiece between the grasping surfaces and rotate the workpiece when the handle is rotated in a first direction; the biasing is overcome when the handle is rotated in a second, opposite direction to cause the plates to pivot within the cavities and spread away from the workpiece so that the grasping surfaces slide over the faces of the workpiece, allowing the workpiece to remain stationary.