Patent ID: 6016678
Filing Date: 2000-01-25
Classification: B21D,Y10T

Abstract:
A tool for expanding an end portion of a tube into engagement with a wall of a hole in a plate and forming a flange on the end of the tube comprising:a mandrel having a longitudinal axis, a tapered portion at a distal end, and a drive portion at a proximal end, the drive portion being adapted to accept a drive device for rotating the mandrel about the mandrel axis;a tubular cage received over the mandrel, the cage being movable axially of and rotatable relative to the mandrel;a plurality of expanding rolls, each of which is supported for rotation in a slot in a distal portion of the cage, is displaceably radially with respect to the mandrel axis, is in rolling engagement with the tapered portion of the mandrel, is adapted to be in rolling engagement with the tube when the tool is in operation, and is skewed at a small angle to the mandrel axis so as to impart traction to the cage and the mandrel and draw them distally into the cage upon rotation of the mandrel;a forming roll supported for rotation and for displacement radially with respect to the mandrel axis in an opening in the cage, the forming roll having:at least one conical following surface that is in rolling engagement with the tapered portion of the mandrel,a conical expanding surface that is adapted to be in rolling engagement with the tube when the tool is in operation,a forming surface immediately adjacent the expanding surface proximally that is adapted to be in rolling engagement with the tube when the tool is in operation, anda conical thrust-receiving surface at a proximal end; andan annular axial thrust bearing supported on and surrounding the cage proximally of the forming roll, wherein the forces exerted on said forming roll by said tube tend to increase the compressive force on said thrust bearing.