GB836902A - Improvements in or relating to sheet metal cutting apparatus - Google Patents

Abstract

836,902. Shearing. TULLY, G. G. Jan. 21. 1958 [Feb. 23, 1957], No. 6147/57. Class 83 (4) [Also in Group XXIII] A cross-cut shear or saw for cutting sheet metal comprises a horizontally reciprocating feed-table 11 which carries a shear blade 19, an eccentrically mounted apron 14a having a rotary motion and which carries a shear blade 15 or a rotating saw blade, means associated with the eccentrically mounted shear or saw blade for holding the sheet during cutting and means for carrying away the cast-off part of the sheet. When used as a cross-cut saw an endless chain saw 33 is mounted on the apron. The feed-table 11 which is reciprocated on rollers or slides by eccentric plates carries guide rollers 32 for the work. The apron 14a is attached to cross-shafts 14 which are moved in orbital path by eccentric plates on stub-shafts 12. Alternatively cranks or eccentrics may impart the motion to the apron. The feed-table and apron are driven from a motor 24 through gearing attached to the framing 10. The sheet to be cut moves continuously through the shear and in order to allow a predetermined length to be cut off a limit switch stops the drive with the upper blade at top dead centre immediately after shearing or sawing. The cut-off work is carried away by a rise and fall feed-table comprising a roller-conveyer pivoted on a reciprocating slide block at a point remote from the shear or saw and oscillated from the shear or saw drive to coincide with the upward movement of the blade 15 or saw attachment. Hydraulically operated work-holders 17, or a single hydraulic clamping plate, are attached to the face of the apron. In a modification, Fig. 5, the blade 15 is attached to resiliently mounted cruciform castings 40 which are reciprocated by eccentric plates as before but have cams 38 interposed in the drive to accelerate the cutting motion.