Abstract: Apparatus is disclosed for holding a generally cylindrical workpiece for honing or otherwise machining an internal bore. The workpiece is held by a gripping surface over most of the innermost turn of a spirally wound torsion band coil. The workpiece is grasped circumferentially over its outer surface without excess contact pressure at any particular point. A tendency of the machining operation to rotate the workpiece serves to secure the workpiece more tightly in position by tightening the outer turns of the tension band coil. A rotatable tensioning member acts under the influence of a biasing spring to decrease the diameter of the innermost turn of the tension band coil to bring the gripping surface into contact with the workpiece. The outer diameter of the tension band coil is variable under the influence of a plurality of segmented support members which are adjustable radially inward and outward to extend the range of utility of the tension band coil.

Abstract: An apparatus and method are disclosed for holding a generally cylindrical workpiece for honing or otherwise machining an internal bore. The workpiece is held by a gripping surface over most of the innermost turn of a spirally wound spring and coil. The workpiece is grasped circumferentially over its outer surface without excess contact pressure at any particular point. A tendency of the machining operation to rotate the workpiece serves to secure the workpiece more tightly in position by tightening the outer turns of the spring band coil. A rotatable tensioning member acts under the influence of a biasing spring to decrease the diameter of the innermost turn of the spring band coil to bring the gripping surface into contact with the workpiece. A method for adapting the work-holding apparatus to smaller or irregularly shaped workpieces consists of molding an annular piece around the workpiece.

Abstract: A work-holding implement for use in honing or otherwise machining the inner surface of a bore in a workpiece comprises a torsion-carrying spring band coil mounted at one end of a handle. Most of the inwardly exposed surface of the innermost turn of the coil is a gripping surface, while the remaining turns in the coil have smooth bearing surfaces. A workpiece is gripped by the innermost turn, and as an interior bore in the workpiece is being honed or otherwise machined, rotational torques exerted on the workpiece by the machine tool cause the coil to become more tightly wound around the workpiece. As the workpiece is being worked on, the tightened coil bears against a planar segment of the spring band forming part of the implement and deforms it into a curved surface conforming to the workpiece surface over which contact is made.

Abstract: An apparatus and method are disclosed for holding a generally cylindrical workpiece for honing or otherwise machining an internal bore. The workpiece is held by a gripping surface over most of the innermost turn of a spirally wound spring and coil. The workpiece is grasped circumferentially over its outer surface without excess contact pressure at any particular point. A tendency of the machining operation to rotate the workpiece serves to secure the workpiece more tightly in position by tightening the outer turns of the spring band coil. A rotatable tensioning member acts under the influence of a biasing spring to decrease the diameter of the innermost turn of the spring band coil to bring the gripping surface into contact with the workpiece. A method for adapting the work-holding apparatus to smaller or inrregularly shaped workpieces consists of molding an annular piece around the workpiece.