GB673995A - Improvements in wrapping machines - Google Patents

Abstract

673,995. Feeding webs. STEPHENS, SMITH & CO., Ltd., and WALSH, T. E. Oct. 3, 1950 [Oct. 3, 1949; May 10, 1950], Nos. 25331/49 and 11649/50. Class 100 (i). [Also in Groups VIII and XVII] A strip of wrapping paper 21 is fed by co-operating intermittently rotating rollers 62, 63 beneath knife means 64 onto a support 22 of a fruit wrapping machine, (see Group XVII), a wrapper sheet being cut from the end of the web when stationary. The feed rollers 62, 63, which are geared together, are driven from a ratchet wheel 75 intermittently turned by a pawl 76 which is pivotally carried by a triangular plate 81 loosely mounted on the shaft 82 of the ratchet wheel 75 and oscillated 180 degrees by a connecting rod 83. A catch 88 in the form of a bell crank is pivotally carried by the plate 81. At the end of the down driving stroke of the pawl a roller 87 carried on the pawl contacts a stationary adjustable cam member 92 to move the pawl out of engagement with the ratchet wheel, a pin 86 on the pawl slipping into a notch 91 in the catch 88 which then holds the pawl out of contact with the ratchet on the upstroke until the catch engages a trip 93 to release the pawl from the catch and allow a spring 90 to pull it into contact with the ratchet wheel for the down stroke. The trip 93 is carried by a lever 117 which moves the trip out of the catchengaging position if an article is not present to be wrapped, thus interrupting the drive to the feed rollers 62, 63. The lever 117 is normally held in the catch-engaging position by the cylindrical part of a cam 119 and, when the profiled part of the cam comes opposite the end of the lever, by a feeler 116 secured to the lever and held up by an article to be wrapped. If no article is then present the lever will move into contact with the profiled part of the cam and move the trip 93 out of catch-engaging position. A serrated knife 105 and presser 104 are carried by a block 106 moved on guides 107 by lever and link means 111, 112 actuated by a cam 114. A band 127 above the web feed bed prevents crinkling of the web. The cam 92 is mounted on a plate 94 adjustable about the shaft 82 to vary the stroke of the pawl and thus the amount of the web fed by each intermittent rotation of the feed rollers 62, 63.