Roll-firmness measuring device

Abstract

A measuring device for determining the pressure zone width and/or surface pressure between a web roll for a web and a further roll of a winding apparatus includes at least one reflex sensor emitting a radiation towards the web roll and receiving radiation reflected from the web roll. The reflex sensor is provided with a source emitting the radiation towards the web roll and a receiver which picks up beams reflected from the web roll. Source and receiver are embedded within the peripheral area of the further roll and are arranged adjacent to each other. During winding of the web, the reception of the radiation is interrupted when the web roll covers the source and/or the receiver. This interruption of the reception is a measure for the pressure zone width and in connection with other variables and constants for the roll firmness.

Dependencies are inferred from the claim text.