Patent ID: 7404310
Filing Date: 2008-07-29
Classification: B21D,B29C

Abstract:
1. A mandrel assembly for insertion into a hollow tube to support the interior walls of the tube during bending of the tube, comprising: a mandrel support rod for inserting and withdrawing the mandrel assembly into the tube; a cam rod carried by the mandrel support rod and having cam surfaces thereon; a plurality of mandrel segments carried by the cam rod and serially arranged and flexibly connected together for flexibly supporting the interior walls of the tube during bending; a plurality of anchor shoes arrayed around the cam rod and having cam surfaces thereon that engage with the cam surface of the cam rod; and a drive mechanism acting on the anchor shoes to move the anchor shoes relative the cam rod so that the anchor shoes selectively move radially outward to engage with the interior walls of the tube and move radially inward away from the interior walls of the tube.