Abstract

Disclosed in a method for manufacturing a drive shaft which comprises forming a first shaft unit by shrinking one side of a metallic pipe which has a uniform first strength; decreasing the thickness of an intermediate portion of the metallic pipe by drawing the intermediate portion of the metallic pipe which is integral with the first shaft unit; forming at an inner side surface of the other side of the metallic pipe a strength decrease unit which has a second strength smaller than the first strength, by heat-treating by a predetermined distance the inner side surface of the other side being opposite to one side of the metallic pipe; and forming a second shaft unit without transforming any portion of the intermediate portion by shrinking the metallic pipe which has the strength decrease unit, wherein the second shaft unit is formed by applying compression force to a portion where the strength decrease unit in the metallic pipe is formed, in a predetermine direction being vertical with respect to the axial direction of the metallic pipe.

IPC Classes  ?

• B21C 1/24 - Metal drawing by machines or apparatus in which the drawing action is effected by means other than drums, e.g. by a longitudinally-moved carriage pulling or pushing the work or stock for making metal sheets, rods or tubes specially adapted for making tubular articles by means of mandrels
• B21D 53/84 - Making other particular articles other parts for engines, e.g. connecting-rods
• B21D 41/04 - ReducingClosing
• B21C 3/16 - MandrelsMounting or adjusting same
• B21C 3/02 - DiesSelection of material thereforCleaning thereof
• B21C 9/00 - Cooling, heating or lubricating drawing material
• F16C 3/02 - ShaftsAxles