| 摘要 |
A device for measuring variations in the web tension occurring transversely across continuously advancing webs, such as paper webs (1). The device comprises a conducting roller (2) mounted at one side of the web (1) in parallel with the web plane and perpendicularly to the direction of travel of the web. The conducting roller (2) is provided with a number of leaf elements (4) of a thin film having piezoelectric properties, said leaf elements being disposed transversely along the roller envelope face (3). Each leaf element (4) has direct or indirect contact with at least one transmitter/receiver means (7) positioned adjacent the conducting roller (2), said transmitter/receiver means (7) arranged, during the advancement of the web (1), to register electric pulses emitted from each one of said leaf elements (4) in response to the web being pressed against said elements. The pulses thus received are transmitted for amplification and processing in order to estimate the variations in the web tension transversely across the web (1). |
