GB832433A - Improvements in or relating to plate shearing machines - Google Patents

Abstract

832,433. Sheaving; metal plate feeds. SVETSMEKANO A.B. Nov. 21, 1957 [Nov. 27, 1956], No. 26284/57. Class 83 (4). In a plate-shearing machine comprising upper and lower cutting tools movably mounted on opposite sides of the plate and movable in planes parallel with the feeding direction of the plate means is provided for positively imparting to the upper tool an oscillating movement in a curved path having one motion component directed transversely of the path of movement of the plate and another directed parallel therewith, said tool being actuated to engage the plate intermittently and thereby to impart a step-by-step feeding motion to the plate, and the lower tool being positioned to be engaged by the plate and to be driven indirectly from the upper tool by the action of the plate pressed into engagement with said lower tool in response to the action of the upper tool. An oscillating shearing tool 1, Fig. 1, is attached to a holder 4 forming part of a double-armed toggle device. The toggle is driven by a crank disc 12 and the lower end of the holder 4 is pivotally attached to a vertically-sliding block 9. A lower shearing tool 2 mounted in a holder 15 on a shaft 16 is spring-biased toward an adjustable shoulder 17. In operation, the tool 1 moves downward to cut a plate 3 which is at the same time gripped between the tools and fed forward by the component of motion of the tool 1 parallel to the plate. The movement of the lower tool is limited by an adjustable stop 19 and the plate is cut step-by-step with a continuous cut. The tools have parallelepipedon shape and have a bevelled cutting edge. In a modification, the crank drive is directly attached to the upper end of the holder 4 so that the cutting edge of the upper tool describes a closed curve. In a further embodiment, Fig. 6, the link 29 of a crank-driven toggle is attached to the upper end of a vertically-guided rod 34, the lower end of which carries a pivoted holder 36 for the tool 1. The feed component of the motion is provided by a pivoted link 37. In a modification of the previous embodiment, Fig. 8, the tool 1 is carried at the lower end of a bar 43 which is driven as before but is restrained by equal links 44, 45 pivoted to an adjustable guide member 50, the feed being effected by the lateral movement of the bar 43 and the tool 1. In a further modification the lower tool is a roller with a cutting edge, the feed being effected by the upper tool with the plate pinched between the tools and the roller rotating on a fixed axis.