GB1233448A - - Google Patents

Abstract

1,233,448. Bending metal sheets to tubular form. CENTRE DE RECHERCHES DE PONT-A-MOUSSON. 28 Oct., 1968 [13 Dec., 1967], No. 51037/68. Heading B3E. A machine for bending metal sheets comprises a plurality of elementary presses having swan-neck frames 2 in alignment in a direction perpendicular to a fixed direction of feeding the sheets, a single anvil 5 being rigidly suspended from upper portions of the frames by as many plane plates 4 as there are swan necks, each plate almost completely closing the opening of the corresponding swan neck and the plates embodying an axial plane of symmetry of the anvil 5 whose working face is directed downwardly towards lower individual bending punches 7 pertaining each one to an elementary press and aligned in a direction parallel to the plane of symmetry. A sheet t is placed on horizontal supports of a feed table of the machine M, so that its rear longitudinal edge is in contact with thrust blocks 14. The sheet t is pushed by the thrust blocks until the forward part is engaged between the anvil 5 and the punches 7. The punches, used by jacks V 1 , exert a bending force on the sheet until the sheet meets the anvil 5. At the same time as the punches 7 are raised, arms 11 of the feed table are pivoted upwardly to the position 11a by jacks V 2 which are synchronized with the jacks V 1 . The advance of the sheet t in step-bystep manner and the press strokes succeed each other alternately until the leading edge of the sheet reaches the plates 4. According to one embodiment two bending machines M 1 and M 2 are used. The sheet t is fed by a conveyer having a driving roller B to the table of the feed device C, of the first machine M 1 wherein a half-tube t<SP>1</SP> is formed. The half-tube t<SP>1</SP> is then taken up by the conveyer carriage E which feeds it in the direction of arrow f<SP>2</SP> to the feed device C 2 of the second machine M 2 , where the tube T is completed. The formed tube T is then discharged from the machine M 2 by an extractor D 2 and transferred to one of two longitudinal conveyers F or G. The tube is then conveyed to one of two welding stations H and I for welding the longitudinal edge of the tube.