| 摘要 |
A web of thermosealing material is intermittently advanced by draw rolls between cooperating sealing and severing heads with the downstream end of the web being advanced onto a pick-off conveyor assembly before being stopped. While the web is stationary, one of the sealing heads is moved into pressure engagement with the other head, with the web disposed therebetween, to clamp, sever and seal the web. The web is transversely severed downstream of the seal and after the severing and sealing operation is completed said one head is moved transversely away from the web; and the other hand is momentarily moved downstream relative to the stationary web for stripping the web from said other head prior to the next cycle of operation of the draw rolls. |
