Abstract: A contacting caliper gauge measures the thickness of a moving sheet material. The gauge has two heads, one on either side of the sheet. The sheet contacting pads of the caliper gauge are aerodynamically designed to limit and/or reduce the tendency of boundary layer air travelling with the sheet to raise the sheet-contacting pads off of the sheet surfaces.

Abstract: A device for characterizing the formation of a sheet material is described. The device comprises a basis weight sensor for measuring the basis weight of the sheet material as the material passes through the sensor and signal processing circuitry which receives a signal from the basis weight sensor indicative of the measured basis weight and which produces three types of outputs, which outputs characterize: (1) the magnitude of variation in the sheet basis weight; (2) the strength of the weakest portion or portions of the sheet; and (3) the size of the flocs comprising the sheet. The basis weight sensor includes a light pipe which is held against the sheet, as the sheet moves through the sensor, and which directs a small spot of light transmitted through the sheet to a light detecting device. The magnitude of variation in the sheet basis weight is computed to be proportional to the true root-mean-square variation in the basis weight of the sheet.

Abstract: A sensor for sensing a quality of a sheet, such as a paper sheet, related to elastic modulus and bending stiffness as it is being made including a sheet support in the form of a ring and a free running wheel, which depresses the paper into the center of the ring as the paper passes over it. A force transducer mounted to the wheel senses the force of the deflected paper on the wheel and provides a measure of a characteristic of the paper related to its elastic modulus and being stiffness. Alternatively, or in addition, a displacement sensor may be used to sense the distance that the sheet is displaced by the wheel into the ring. These factors, together with basis weight, thickness and paper velocity may be used to determine the strength of the paper on a continuous basis.