Patent ID: 7024908

Claim:
A puller tool for cold working an opening in a workpiece, the puller tool comprising: an elongated mandrel having a first circumference portion sized to radially expand the opening in the workpiece; an elongated first tubular member having a mandrel receiving center passageway and a slotted outer end portion comprising first axial fingers separated by first axial slots; an elongated second tubular member surrounding the first tubular member and having a slotted outer end portion comprising second axial fingers separated by second axial slots; an elongated third tubular member surrounding the second tubular member and having a slotted outer end portion comprising third axial fingers separated by third axial slots; the third fingers having outer end portions forming an end opening and including radially inwardly projecting clamp jaws having substantially radial first clamp surfaces; the first axial fingers including outer end portions having substantially radial second clamp surfaces which confront the first clamp surfaces; the first tubular member being extendable and retractable longitudinally with respect to the second and third tubular members; the first and second tubular members having first and second cam surfaces, the first cam surfaces being radially outwardly directed on the first axial fingers and the second cam surfaces being radially inwardly directed on the second axial fingers; the first and second cam surfaces being adapted to contact each other and expand the second axial fingers radially in response to the first tubular member being retracted into the second tubular member, and the expansion of the second axial fingers being adapted to cause an expansion of the third axial fingers and an enlargement of the end opening formed by the axial fingers of the third tubular member; a tubular sleeve having an inner end and a flange projecting radially outwardly from the sleeve at the inner end, the flange being sized to move axially through the end opening in the outer end of the third tubular member when the third axial fingers are expanded, and the flange being sized to be received between and be clamped by the first and second clamp surfaces when the first tubular member is extended axially and the second and third axial fingers are contracted radially; the tubular sleeve having a tubular portion that extends axially from the flange and the end opening when the flange is clamped by and between the first and second clamp surfaces; the mandrel being extendable axially through the center passageway of the first tubular member and axially through the tubular sleeve when the radial flange is clamped by and between the first and second clamp surfaces; and the mandrel being retractable through the sleeve and into the center passageway, when the radial flange is clamped by and between the first and second clamp surfaces.