HEAT-TREATMENT OF WRAPPERS IN CIGARETTE PACKING MACHINES &C

摘要

The heat-sealing tool for closing the thermoplastic transparent outer wrappers of cigarette packs in a cigarette packing machine is pivoted intermittently into engagement with the wrappers of successive packs while the indexible turret which transports the packs is idle. The tool is held in engagement with each of a series of wrappers for the same interval of time irrespective of the speed of the prime mover which drives the turret. To this end, the tool is pivotable by a rotary disc-shaped cam which is driven by a variable-speed motor whose operation is regulated by a control circuit including a function generator. Alternatively, the tool is actuated by a transmission which receives motion from the prime mover and is adjusted when the speed of the prime mover changes.