GB643807A - Improvements in or relating to cutting and forming machines - Google Patents

Abstract

643,807. Making screens. STEVENS, A. H. (Flex-o-Glass, Inc.). March 9, 1948, No. 7227. [Classes 83 (ii) and 83 (iv)] Shearing; angular bending ; flanging dies.- A machine for making insect-screen mesh comprises two sets of rollers, the first set of which slits a sheet and partially bends the slit portions and the second completes the bending of the slit strips. The rollers are formed of saw-like discs strong with spacers on shafts 79, 82, 103, 104, mounted in side frames one of which is removable for changing the rollers by screw means, and rotated from a power shaft through gearing adjustable by eccentric means to take up back lash. The upper roll shafts 82, 103 are adjustable by screws 65. The sheet is fed into the machine over a table 159, is slit and bent by the rollers and is fed from the machine by rollers 164, 165 which may maintain the sheet under tension. The 'discs forming the rollers on shafts 79, 82 are serrated, Fig. 13, with surfaces 85 which cooperate to slit the sheet and surfaces 87 which bend the slit portion out of the plane of the sheet. The edge part of the disc carries a surface 89 which curls or flanges slightly the edge of the slit portion. The discs on shafts 103, 104 complete the bend as shown in Fig. 14. In order to facilitate the bending the shaft 103 is rotated at a speed slightly greater than that of the sheet and the roller 164 is rotated at a speed slightly less. The angular position of the teeth is varied by eccentric adjustment of the rollers and the period of engagement of the teeth with the slits is varied by adjustment of the screws 65. Stripper bars 182 are positioned between the bending discs.