Patent ID: 7799172

Claim:
A device for measuring tension or a tension change in a paper web, said device comprising: a plurality of measurement bodies facing a surface of the web; a plurality of fluid supply devices to apply a fluid pressure to the web, whereby the fluid supply devices are arranged to subject the web to an essentially constant fluid pressure in order to provide a fluid cushion between the web and the measurement bodies to space the web from the measurement bodies, whereby the measurement bodies are arranged for displacement toward and away from the web surface and are arranged to apply pressure to the web from fluid supplied by the fluid supply devices and without the measurement bodies making contact with the web, whereby the position of the measurement bodies in the normal direction relative to the web surface is changed depending on variations in the physical characteristics of the web, wherein the measurement bodies are adjacent to each other in a row and substantially side-by-side relative to each other and substantially perpendicular to the longitudinal direction of the web, wherein the device includes a plurality of web supports facing an opposite surface of the web from the surface of the web that faces the measurement bodies, the web supports having orifices facing the web, and means for conveying a fluid to flow through the web support orifices and towards the web to form a fluid cushion between the web supports and the web and arranged to regulate the position of the web relative to the web supports and to space the web from the web supports.