GB1033424A - Shears for cutting profile sections - Google Patents

Abstract

1,033,424. Shearing profile bars. VSESOJUZNY NAUCHRO - ISSLEDOVATELSKY I. PROEKTO - KONSTRUDTORSKY INSTITUTE METALLURGICHESKOGO MASHINOSTROENIJA. April 30, 1964, No. 17949/64. Heading B3W. A shear for cutting profile bars comprises first and second cutter holders travelling to meet each other and is characterized in that each holder carries a plurality of blades together forming a cutter assembly, the first cutter holder has one blade rigidly fixed thereto and a seond blade attached movably by a device for moving the blade in a direction different from that of the travel of the cutter holder, and the second cutter holder has one blade connected to the holder so as to be able to move relative to the holder in the same direction as the travel of the holder and a second blade attached movably by another device for moving the blade in a direction different from that of the travel of the cutter holder. The cutter supports 1, 2, Fig. 1 (not shown), are mounted on double-cranks 3, 4 and 5, 6 respectively, and each support carries a composite cutter consisting of two blades 7, 8 and 9, 10 respectively. The cutter 7 is fixed in the support 1 and the cutter 8 is attached to the support by pivoted links 12<SP>1</SP> and 13. A spring acts on the link 12<SP>1</SP> to return the cutter 8 to its initial position after a cutting stroke. The cutter 9 slides in guides 11 in the support 2 and is displaced by the cutter 7 against the action of a spring 12. The cutter 10 is attached to the support 2 by pivoted links 14 and 15. A return spring 17 acts on the link 15. Should the blades 8 and 10 become jammed they are positively returned at the end of the cutting stroke by push rods 18, Fig. 5 (not shown), operated by the cranks 3 and 4. To maintain the correct clearance between the cutters a taper pin on the support 2 enters a corresponding bore in the support 1 during the cutting phase of the cycle. Operation.-An I-section beam 20 is first held between the cutters 7 and 9 and as the supports 1 and 2 continue to approach the blade 9 is depressed by blade 7 and blades 8 and 10 are forced to move on their link attachments and co-operate with the blades 7 and 9 to cut the beam. Blade 8 moves at approximately 45 degrees to the web of the section and blade 10 moves approximately horizontally. In a modification, the blade 8 is mounted on a single pivot, Fig. 10 (not shown), and in a further modification, the blades 8 and 10 are each mounted in guides to slide at a pre-set angle to the direction of travel of the cutter supports, Fig. 11 (not shown).