摘要 |
A tubular web processing apparatus for a packaging machine for forming and sealing a tubular web has a pair of sealing jaws (7) reciprocating in the longitudinal direction of the web (W) by a first drive rod (9), and being driven for opening and closing movement by a second drive rod (10) operated by a cam follower arm (4) engaging the outer surface of a rotary cam (2). To prevent this engagement of the cam follower arm (4) from the rotary cam (2), the rotary cam (2) has a laterally projecting arcuate guide member (12) and the cam follower arm (4) has an auxiliary roller (15) engaging with the radially inner surface of the arcuate guide member (12). In an alternative embodiment the cam follower arm (4) is connected to the drive rod (10) by means of an overload cuppling device (22, 24, 25). |