GB764369A - Packaging machines - Google Patents

Abstract

764,369. Packaging-machines. IVERS-LEE CO. Feb. 8, 1955 [June 3, 1954], No. 3680/55. Class 94(1). [Also in Group VIII] In a packaging machine in which pellets are arranged in sealed and spaced relationship between two webs C, Fig. 1, the webs are cut to form packaging units by being continuously fed by heat sealing and crimping rollers 1, 2 between co-acting cutting blades 43, 67, the blade 67 being moved towards the blade 43, to cut the material, by a fluid-pressure operated piston 58, Fig. 3, movable in a cylinder 49 against the action of a spring 63, the flow of fluid, e.g. air, to the cylinder 49 being controlled by valve mechanism 78, Fig. 5, which is actuated by means including a cam ring 87 rotated in synchronism with the feed rollers 1, 2 and having cam surfaces 90 spaced apart in accordance with the lengths of the required units, the cam ring being engaged by a follower roller 117 which is operatively connected to a rotatable indexing disc 112 so that the disc is intermittently actuated in timed relation to the spacing of the cam surfaces 90, the valve mechanism 78 being controlled by the movement of the disc 112. The follower 117 is mounted on one arm of a spring-influenced pivotally-mounted bell-crank lever 111, Fig. 5, the other arm of which has pivoted thereto a spring-influenced lever 113 provided with a pointed extension 141 adapted to engage teeth on the indexing disc 112 and with a tipped end 137 adapted to engage an extension 108 on a spring-influenced valve member 106 (not shown) mounted in a valve casing 97. The indexing disc 112 is provided with short teeth 132 and with spaced-apart longer teeth 134. The cam ring 87 is provided with a plurality of axiallyspaced cam tracks 89, the follower 117 being movable along its axis to be engaged with the desired cam track and the indexing disc 112, which is removable, being selected. so that the number of longer teeth provided thereon equals the number of cam spaces provided in the selected cam track. The position of the cam ring 87 may be initially adjusted relatively to the follower 117 by turning the cam ring on a circular plate 83, Fig. 5, which has a marker 156 co-operating with a scale 155 on the cam ring. In operation, the completed package strip fed from the rollers 1, 2 is pulled downwardly by a pair of auxiliary feeding brushes 145, 146, Fig. 1, and passes into an opening 35, Fig. 3, in a plate 31 to the cutting blades. The rotation of the feed rollers causes a simultaneous rotation of the cam ring 87. When a cam surface 90 moves into engagement with the follower 117, the latter drops into the cam depression permitting the lever member 113 to be pulled downwardly by spring action so that its extension 141 engages one of the short teeth 132 on the indexing disc 112 to move the disc one step. Continued rotation of the cam ring 87 causes the lever member 113 to rotate the disc 112 step by step until a large tooth 134 is reached when the lever member 113 is permitted to move downwardly and to swing laterally forcing its tipped end 137 downwardly against the extension 108 on the valve member 106 (not shown) to allow air under pressure to enter the cylinder 49 behind the piston 58. Movement of the piston forces the cutting blade 67 rapidly across the cutting blade 43 to sheer off the packaging material. When the cam surface 90 is moved away from the follower 117, the bell-crank lever 111 moves the lever 113 away from the valve member 106 (not shown) permitting the latter to rise under spring action to shut off the supply of air and simultaneously permitting the spring 63 to retract the piston 58 in the cylinder 59. Specification 441,315 is referred to.