Abstract: A coat weight control system for applying coating to a paper sheet in a paper machine permits even coating across the sheet with less actuator force needed. The system applies a specified force profile on a coating blade and has a plurality of actuators spaced apart, the actuators each applying a load. A flexible backing bar is positioned on the coating blade having connections there along to the actuators, the backing bar having a plurality of keyhole slots between the connections, the slots spaced apart along the bar.

Abstract: A process for determining shrinkage and alignment of the web in a sheetmaking machine having a plurality of actuators for controlling web parameters in the cross-direction. The process involves the steps of applying excitation to the actuators, collecting data regarding the change in cross-direction web properties due to the excitation of the actuators to determine a measured actuator response profile. A modeled actuator response profile is established and a best fit of the modeled actuator response profile to the measured actuator response profile is established to allow for determination of alignment and shrinkage parameters of the web based on the best fit modeled actuator response profile. The foregoing approach permits reliable identification of alignment and shrinkage within 10-20 data scans of the web, despite process noise, with improved accuracy when compared with conventional "bump" tests.

Abstract: A coupling member for joining a first article to a second article comprising first and second elongate arms that are pivotally connectable to a main housing via ball and socket joints. Each arm has one end formed for connection to one of the articles and the other end adapted to be engaged in the ball and socket joint. A locking system is also provided to lock the arms in position with respect to the main housing after the arms have been connected between the first and second articles to create a rigid connection between the first and second articles. The pivotable nature of the coupling member allows for a connection to be made between the first and second articles to be joined without the articles being in perfect alignment whereupon the locking system is applied to create a rigid link.

Abstract: A steam applicator to apply steam to a web passing by the applicator. The applicator is a main supply header and a plurality of profiling steam chambers to receive steam from the main supply header. The pre-heat chambers adjacent the profiling steam chambers. The flow of steam is controlled from the main supply header to each profiling steam chamber. At least one outlet in each profiling steam chamber allows a supply of steam from the applicator. The supply of steam from each outlet can be controlled. The apparatus is compact and has the virtue avoiding condensate dripper onto the web.

Abstract: Apparatus for distributing a heating medium, such as steam or hot air, to a paper web or calendar roll in sheet making machinery includes a removable profile screen to permit easy cleaning and maintenance. The apparatus comprises an elongated chamber to receive steam or hot air from a supply source with a front wall adapted to receive a removable screen. The removable screen is flexible and defines at least a portion of the front wall conforming generally to the shape of the adjacent surface to be heated. The screen member has a plurality of apertures through which the heating medium is forced to heat the surface. The screen is removably mounted to the apparatus by clip members.

Abstract: A method for determining the cross-machine shrinkage or expansion profile of a travelling sheet produced in a sheetmaking machine between an upstream location and a downstream location. The method involves marking the sheet at the upstream location with an array of marks at measured, predetermined intervals in the cross-machine direction. The sheet is inspected in the cross-machine direction at the downstream location to measure the spacing of the array of marks. A shrinkage or expansion profile of the travelling sheet is developed based on the changes in the spacing between the array of marks at the downstream location. Apparatus for carrying out the method is also disclosed. The method and apparatus of the present invention permit rapid and precise determination of the sheet shrinkage or expansion profile to allow for better control of property variation across the sheet.

Abstract: An actuator converts rotational movement to linear movement and at the same time transmits a limited linear force without requiring slip clutches or the like. The actuator has an electric motor in a fixed housing with a drive shaft on a longitudinal axis. A drive gear, substantially free of backlash, is connected to the drive shaft and has an output connection to drive a drive nut with an internal screw thread on the rotary axis. An output shaft has an external screw thread engaging with the internal screw thread of the drive nut and moves linearly when the drive nut is rotated. A voltage control system allows the voltage to the motor to be set so that for a set voltage there is a predetermined longitudinal force on the output shaft.

Abstract: A caliper profile control system for a paper machine provides reduced start up times after sheet breaks to bring the caliper profile across the sheet to within the desired limits. The method comprises the steps of scanning at predetermined intervals across the width of the paper sheet to monitor thickness error of the sheet from predetermined limits and change in the thickness error between the intervals, in each of a plurality of zones across the sheet. A control change signal is determined for each of the zones based on the error and the change in error using an exponential function of the magnitude of the error to maximize the change in the error and reduce integral action when the error is large. The control signal is used to reduce the error in each zone and the integral action is increased as the error decreases until the predetermined limits are met.