Thermoplastics bag delivered from prodn. machine - to stacking device through braking device with variable action

摘要

Machine for the prodn. of seal-welded thermoplastics bags has a conveyor for feeding the finished bags from the completion station to the delivery station. Before reaching the stacking point the sheets are retarded by a braking device. This braking device is designed so that it can be switched from a full braking action. reqd. when the speed of delivery is high, to a reduced braking action which is used when the speed of delivery is low. To switch over from one speed to the other a control device is used, which operates as a function of the rotational speed of a transmission component of the feed device. At the full operating speed of the machine, when the completed bags leave at high speed, the full braking action is required, whereas when the machine is operated at reduced speed, for instance at start-up or during maintenance, a lesser retarding action is reqd. and the reduced braking action is then used. In this way a neat stack is obtd.