GB659935A - Improvements in or relating to apparatus for selecting samples - Google Patents

Abstract

659,935. Punching-apparatus. UNITED ENGINEERING & FOUNDRY CO. April 6, 1949, No. 9370. Convention date, May 4, 1948. [Class 31 (ii)] [Also in Group XXII] In a machine for punching out samples from a moving strip a selectively-operated punch and a co-operating die are carried in a pair of drums between which the strip passes. The drums 17, 19 are keyed on intergeared shafts 22, 23 in frames 12, 14 on a trolley 11 which is moved along tracks 16 by a hydraulic piston 28 to make cuts over any part of the width of the strip S. An electric motor 27 mounted on the trolley 11 and controlled by a rheostat 27a drives the drums and is coupled to a tachometer generator 34. The punch 21 slides in a radial slot in the drum 19 and is projected beyond the drum face or retracted by solenoids 41, 42 operating through a crank 45, ball-jointed pushrod 49 and toggle links 51, 52 pinned at 54, 58 to the punch and a diametrically opposite abutment on the drum respectively. The co-operating die 71 is slidably mounted in a cylinder 18 containing a resilient ejector 72 and located in a large aperture in the drum 17 by bolts which permit adjustment for registration with the punch 21. The drums 17, 19 have bevelled edges and are enclosed in casings 78, 83 flared in line with the bevels to act as guides for the strip which, after passing between the drums, is subjected to an air blast from a shoot 85 for deflecting the sample upwards, the strip then being deflected downwards over a roller 91 while the sample passes to a collector 86. The solenoids 41, 42 are arranged to operate the punch 21 to take a single sample as required by a system. of electrical relays, the first of which is brought into operation when the voltage of the tachometer generator 34 reaches a predetermined figure, whereupon the solenoid 42 is operated to withdraw the punch 21 within the drum. When a sample is required to be cut a push-button is depressed which brings a further relay into operation which permits a cam-type limit switch 31 on the drum shaft 23 to switch on the solenoid 41 through a further relay, causing the punch 21 to project from the drum and after a cut has been made to switch on the solenoid 42 again so that the punch is withdrawn. The final movement of the switch 31 simultaneously releases the relay closed by the push-button so that the cutting operation is not repeated until required.