Abstract: A single sided reflectance sensor having an optical arrangement which permits accurate measurements of select physical properties of a moving sheet. The sensor comprises a protective enclosure, positioned adjacent to a sheet surface, containing an electromagnetic radiation source disposed to project an incident beam onto the sheet surface, a reflectance sensing means for sensing the intensity of the reflected portion of the incident beam, and a planar convex lens, located between the source and the sheet. The shape and orientation of the lens source and the sheet. The shape and cross-direction and/or render the sensor substantially insensitive to sheet flutter.

Abstract: A system for detecting optically-sensitive properties of sheet materials during manufacture includes a first group of bundles of optical fibers that convey light to selected transmitting locations adjacent one face of the sheet material. The system further includes a second group of bundles of optical fibers that collect and convey light transmitted through the sheet material to a light detector. The light detector measures the intensity of light received from each of the bundles of the second group to provide measurements of optically-sensitive properties of the sheet material at selected cross-directional locations.

Abstract: A system for measuring the values of a parameter of a sheet of material is provided. The system includes a head system with sensors mounted therein and a distance correction system to correct the measured parameter for variations in the distance between parts of the head system.

Abstract: The present invention is directed toward a controller for controlling local calender roll diameters by directing temperature controlled fluid against selected slices of a rotating calender roll. The calender roll has a diameter which responds to changes in temperature. Therefore, thermal expansion or contraction, resulting from localized heating or cooling of the calender roll by the temperature controlled fluid, corrects local non-uniformities in the spacing between cooperating calender rolls. The invention conserves energy by recirculating the temperature controlled air.

Abstract: A contacting caliper gauge measures the thickness of a sheet material moving from the anterior to the posterior of the gauge. The gauge has two matched heads, one to either side of the sheet. Each head has a base, a skid and a bellow. The skid is hinged to the anterior of the base and is between the base and the sheet. The other end of the skid is attached to a bellow. The bellow is also attached to the posterior of the base and is substantially perpendicular to the sheet. A cap is attached to the bellow. The cap has a surface parallel to the sheet near the posterior and rounded near the anterior. The two heads are positioned with the bellow of one in line with the bellow of the other. In a preferred embodiment, the gauge further comprises means for permitting the skid of each head to rotate about an axis which is substantially perpendicular to the hinge near the anterior of the base.

Abstract: A contacting caliper gauge measures the thickness of a sheet material moving from the anterior to the posterior of the gauge. The gauge has two matched heads, one to either side of the sheet. Each head has a base, a skid and a bellow. The skid is hinged to the anterior of the base and is between the base and the sheet. The other end of the skid is attached to a bellow. The bellow is also attached to the posterior of the base and is substantially perpendicular to the sheet. A cap is attached to the bellow. The cap has a surface parallel to the sheet near the posterior and beveled near the anterior. The two heads are positioned with the bellow of one in line with the bellow of the other.

Abstract: A caliper gauge for measuring the thickness of a sheet has a transmitter generating a magnetic field on one side of the sheet and a receiver detecting the amplitude of the magnetic field on the other side of the sheet. Both the transmitter and receiver are maintained at a constant distance from the sheet. The transmitter comprises an electrical wire wound a plurality of times about a cylindrically shaped body of a magnetically susceptible material. The receiver also comprises a cylindrically shaped body with an electrical wire wound a plurality of times about it. The transmitter is positioned such that the axis of the cylindrical body is substantially perpendicular to the sheet. The receiver is positioned such that the axis of the cylindrical body is substantially aligned with the axis of the transmitter.