METHOD FOR PRESS BURNING OF METALLIC TUBE AND BURRING TOOL USED THEREFOR

摘要

PURPOSE: To enhance the workability and mass-productivity for the burring of a metallic tube and improve the working accuracy of a hole after its opening. ;CONSTITUTION: A prepared hole 3 is opened at a specific position of a tube 1, and a burring tool 10 consisting of a punch member 11 is positioned inside the tube 1 corresponding to the prepared hole 3. This punch member 11 is moved outside from inside the tube 1, the circumferential edge part 3a of the prepared hole 3 is bent up outward by the raising working part 12 of the punch member 11, and the raised opening part 2 is worked for raising. A drawing is applied on the inside circumferential surface of the raised base part 2a of the raised opening part 2 of the tube 1 after this raising working, by means of the drawing working part 13 of the punch member 11, with the height of the raised opening part maintained.;COPYRIGHT: (C)1995,JPO