GB788632A - Air powered stapling machine - Google Patents

Abstract

788.632. Stapling machines. HORNE, R. F. (International Staple & Machine Co.). March 15, 1956, No. 8130/56. Class 89(3) The drive blade 60, Fig. 3 of a known stapling, machine is secured to the rod 54 of a single-stroke compressed air actuated piston 53 which is normally held against the cylinder head 52 by compressed air admitted through a line 72 in the handle 22 past a valve member 84 of a two-part main valve 83, 84 into ducts 75, 82 leading to the underside of the piston 53; the cylinder space above being vented to atmosphere through a duct 112, Fig. 2, an open valve member 116, Fig. 5, of a two-part poppet valve 115, 116 and an exhaust duct 78. The downward working stroke of the piston 53 and hence of the blade 60 is initiated by an upward pull on a trigger 130 whereupon a spring-biased cam 131 is rocked counterclockwise about a pin 134 and lifts the rod 86 of the main valve so as to force it to its other position. Simultaneously the poppet valve is switched by virtue of release of compressed air trapped below the piston 53 being vented to atmosphere. Initiation of the return stroke is effected by abutment of a screw 69 at the end of the piston rod 54 against a dog 142 of cam 131 resulting in sufficient clockwise rotation of cam 131 about its pin 134 to free the valve rod 86 irrespective of whether the trigger is being held up or not. In a modification the trigger comprises balls pressed by springs into a recess in the main valve rod and in a further modification the trigger is solenoid operated. The top of the driving blade 60 is connected by two pivoted links 62 to two anvils 63 rockable about fixed pins 64 and carrying clinching arms 65.