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 and process for continuously determining the strength of paper sheet material during manufacture includes a plurality of sensors for detecting proxies related to properties such as the strength of individual fibers, length distribution of fibers, quantity of fibers, distribution of fibers, orientation of fibers, number of bonds between fibers, and bond strength of fibers. For a given papermaking machine and paper type, multiple regression analysis is used to determine correlations between the measured proxies and laboratory tests of paper strength. Then, during operation of a papermaking machine, changes in the proxy measures are used to indicate paper strength and to adjust operation of the papermaking machine based upon changes in the strength of sheet material being produced.

Abstract: An x-ray sensor for determining the amount and composition of a multi-component material is disclosed. The sensor is particularly useful for determining the amount and chemical composition of a coating spread on a continuously moving paper sheet or filler material mixed into such a sheet.

Abstract: A system and process for controlling the displacement of a thickness regulating member which regulates the basis weight of a sheet being formed from fluid material. The displacement of the thickness regulating member is determined by measuring the forces which slice rods exert on the thickness regulating member.

Abstract: A system for controlling the calendering of sheet materials includes means for receiving measurements of one property of sheet material during production wherein the input to the system represents the setpoints of a calender profile actuator system. In operation, the system first calculates a linear trend line from a pattern of setpoints. Then, the linear trend line is substrated from the pattern of setpoints and used to control an edge loading system. The residual setpoints are provided to a frequency splitter whose low frequency output is used to determine the setpoints of a crown roll system and whose high frequency output is used to determine the setpoints of a calender profile actuator system.

Abstract: A system for measuring the open space between, and the ratio of open space to cord diameter, of cord reinforced tire fabric. A collimated x-ray source and detector scan across the tire fabric as it is calendered providing a signal corresponding to each edge of a cord. A counter counting at a constant rate provides a time interval measurement of each open space, and also of the corresponding open space plus cord, as the x-ray source and detector scans the fabric. The quotient of the two time intervals determined is proportional to the fractional open space at a particular location in the fabric. An alarm is provided to indicate when the open space is outside predetermined limits.

Abstract: The specification discloses a steambox for assisting in the drying of sheet material. The steambox has a means for preventing steam which condenses inside the steambox plenum from dripping onto the sheet. The steam is jetted from the plenum toward the sheet through a single cross-directionally oriented slot to decrease entrainment of ambient air and thereby increase heating efficiency.

Abstract: A sensor is disclosed for sensing a physical property of a sheet material. The sensor includes a mechanism for supporting one side of the sheet along the periphery of a defined region and a mechanism for forcibly deflecting the sheet into the unsupported center of the defined region. A transducer may also be incorporated to sense the force required to deflect the sheet into the unsupported region and/or the distance that the sheet is deflected into the unsupported region. The sensor may be operatively coupled to a computer programmed to determine a physical property of the sheet based upon the sensed force and/or distance, such as the sheet failure strength.

Abstract: A device, system, and method for measuring the strength of a sheet material during or after the manufacturing process are described. The present invention forms a chamber having one wall consisting of the sheet material to be tested. A high pressure air supply feeds into a reservoir which is in flow communication with the chamber by way of a valve. High pressure air is injected into the chamber, and the sheet ruptures. A pressure transducer measures the pressure in the chamber. The pressure measurements are differentiated, and a peck detector detects the peak derivative value obtained and thus the time at which the sheet ruptured. A computer determines the pressure in the chamber at the time that the sheet ruptured.

Abstract: A linear actuator having an actuator member driven in a linear direction by a lever mechanism pivotally coupled thereto which is in turn driven by a plurality of on/off linear drivers. Driving the linear drivers through varying stroke distances provides a sequence of discrete actuator steps. By providing an interconnected simple lever mechanism a discrete set of 2.sup.n steps may be provided for n drive positions and n on/off linear drivers. The linear actuator thus provides simple integration with a digital control system and precise positive discrete steps of linear actuation.

Abstract: A system and method for controlling sheetproducing machines includes measurement devices for measuring properties of a sheet at cross-directional locations to provide cross-directional profiles, and spatial-frequency splitting means for separating low spatial-frequency components from high spatial-frequency components for each profile. The separated high and low spatial-frequency components provide operating signals to controllably adjust properties of the sheet.

Abstract: A sensor and a method for determining the basis weight of coating material on a substrate is described. The determined basis weight is insensitive to changes in the amount of substrate material underlying the coating. Signals from the sensor may be used in the control of a coating mechanism to provide a coating having a uniform basis weight.

Abstract: To determine machine-direction variations in measurements of a travelling sheet during production, the sheet is repeatedly traversed with a scanning sensor and, during each traverse, measurements are taken at a plurality of locations. Then, a series of reference slice locations are selected which extend in the true cross-direction. For the reference locations, measurement values are estimated based upon actual measurements. Then, for each scan, the average of the estimated measurement values is calculated. Next, cross-directional variations in values at each slice location along selected scans are calculated by subtracting the average value from the estimated value at each location along the scan. During the next consecutive scans, machine-directional variations in the sheet property at slice locations are calculated by determining the difference between the measured value and the calculated cross-directional variation value for that slice location along the prior scan.

Abstract: A gloss sensor for optically measuring the gloss or reflectance of a surface. The gloss sensor includes a light source of emitting a light beam toward a surface to be measured. The gloss sensor also includes a light detecting device arranged to preferentially detect the intensity of the diffusely reflected component of the reflected light beam relative to the specularly reflected component.

Abstract: The present invention relates to a method, or process, for deriving compositional information from a multi-layer composition which includes the steps of obtaining multi-layer fractional composition information using a non-contact gauge such as an FTIR gauge; obtaining additional multi-layer composition information using a beta gauge; and, correcting for beta ray absorption differences among the layers of the multi-layer composition by combining the multi-layer fractional composition information with the additional multi-layer composition information obtained using the beta gauge.

Abstract: A running blade is adapted to move at the same speed as a continuously running sheet and to generate a burst perforation through the sheet. The force exerted by the blade against the sheet is measured and used to calibrate a non-destructive sheet strength sensor.

Abstract: A method and device for determining the strength of a sheet material, such as paper, utilizing floc size and the variability of the local basis weight of the sheet. The force required to deflect the moving sheet out of a nominal position, the distance the sheet is deflected by said force and the average tension applied to the sheet may also be utilized in the above determination of sheet strength.

Abstract: An infrared paper web moisture sensor is described which comprises a source of infrared radiation for directing an infrared beam through the web and an infrared detecting unit disposed on the opposite side of the web from the infrared source. In one embodiment, the infrared detecting unit measures the transmission of the infrared beam through the web at three separate wavelength regions of the infrared spectrum, one of which is sensitive to web temperature. In a second embodiment, the infrared detecting unit measures the transmission of the infrared beam through the web at two separate wavelength regions of the infrared spectrum, one of which is insensitive to web temperature. For each embodiment, signals are developed indicative of the transmission of infrared through the web in each of these regions, digitized, and fed to the process control computer for the paper mill.

Abstract: A method for controlling high-speed sheetmaking machine after abrupt process changes and during start-up periods, includes operating a scanning sensor to periodically traverse back and forth across a sheet in the cross direction to detect values of selected sheet property along each scan while the cross-directional width of each scan is controlled to be substantially less than the width of the sheet being scanned, the progressively increasing the width of the scan until each scan encompasses the full width of the moving sheet.

Abstract: A system for determining the basis weight of cord reinforced tire fabric which involves the use of two radiation source, for example a collimated x-ray beam, and a beta ray source. One of the radiation sources and its corresponding sensor (e.g., the x-ray source) is used to determine the fractional area of the fabric not containing steel cords, while the other (e.g., the beta ray source) is used to measure the average attenuation of radiation passing through the fabric. Both sources and their corresponding sensors are movably mounted on a pair of beams which extend across the width of the fabric web. The source sensor assemblies continuously scan across the fabric width so that information from the entire fabric area is obtained.