Machine for producing paper bags has perforating knife, peripheral speed of which can be changed during rotation about shaft

摘要

The bag producing machine has a device (1) for transversely perforating the web (8). The device includes at least one perforating knife rotating round a shaft (2) to make transverse perforation cuts in the web, and a counter-pressure roller (7) to transport the web and to provide the counterforce. The peripheral speed of the perforating knife can be changed during rotation round the shaft.