Apparatus for Making Tubes from Sheets of Metal

24,695. Schmale, P. Nov. 17. Bending.-In apparatus for making tubes from sheets of metal, a moving mandrel 6, Figs. 2, 3, and 6, forces the sheet 13 into a matrix 8 and other and pivoted parts of the die such as 9, Fig. 3, or 9, 9, Fig. 6, are closed on the sheet. The pivoted parts of the die leave the abutting edges of the sheet exposed for uniting them and the die parts are locked by a spring catch 15. The mandrel 6 is supported in bearings carried by spring-pressed rods 2 and is lowered by a cross-bar 12 and links 11, 10. When the cross-bar 12 is released the die moves upward with its enclosed tube and at the same time it is rotated by hand so that the edges of the sheet are uppermost. The edges may be bent by a preliminary operation by means of a rail 18.