Spiral duct forming tools and spiral duct deformation method

摘要

PROBLEM TO BE SOLVED: To uniformly and easily deform a cylindrical metal spiral duct compressed axially into a flat cylindrical shape such as an elliptical cylindrical shape to obtain a good finished product using a deformation tool.;SOLUTION: A duct deformation tool 10 is constituted by upper and lower division bodies 20, and includes in an assembly state: a circular lead-in port 11 into which a spiral duct D is led; an elliptical lead-out port 12 from which the spiral duct D is led out; and a radial compression portion 13 provided between the lead-in port 11 and the lead-out portion 12, gradually deforming a cross-section of the spiral duct D from a circular shape to an elliptical shape from the lead-in port 11 toward the lead-out port 12, and radially compressing the spiral duct D. The lead-in port 11, the lead-out port 12, and the radial compression portion 13 are formed to have a generally identical circumferential length. While the spiral duct D is elongated by pulling the spiral duct D from the lead-out port 12, the spiral duct D is compressed radially by the radial compression portion 13 and deformed into an elliptical shape.;COPYRIGHT: (C)2014,JPO&INPIT