Patent ID: 7310926

Claim:
An apparatus for producing film tube which can be filled with liquid, viscous or granular filling material, from a film strip, the apparatus comprising: a filling tube which can be connected to a filling machine, a transformation device surrounding the filling tube for transforming the film strip into a film tube, a sealing device arranged downstream of the transformation device in a filling expulsion direction for sealing longitudinal edges of the film strip, the longitudinal edges are positioned adjacent to each other by the transformation device, an advance drive means for transporting the film tube to a buffer, the advance drive means being arranged downstream of the transformation device, and a device for determining a supply of film tube delivered by the advance drive means-to the buffer based on the difference between the length of film tube supplied to the buffer and the length of film tube withdrawn from the buffer absent measurement of the film tube length in the buffer, the device-including a first sensor which detects a length of the film tube delivered by the advance drive means to the buffer, a second sensor which detects a length of the film tube withdrawn from the buffer in the filling expulsion direction, and an electronic regulating system operably connecting to the first and second sensors.