Patents Assigned to Sistig Corporation
  • Patent number: 4341335
    Abstract: Method and apparatus for controlling tension in a longitudinally moving web between fixed material feeding points while maintaining the length of the path of web movement between said fixed points substantially constant. Two axially fixed, web-feeding rollers are positively driven from a common drive motor. One roller is driven at a variable speed through a shaft-mounted transmission unit having a variable pitch pulley spaced from the axis of rotation of the roller shaft and connected to the motor by a flexible belt. Fluid piston means provides a constant force on the transmission unit in a direction about the roller shaft axis to impose a constant torque on the variable speed roller and to move the variable pitch pulley to increase or decrease the speed of the roller, thereby maintaining a constant imposed tension on the material in its path of movement between the two rollers.
    Type: Grant
    Filed: October 7, 1980
    Date of Patent: July 27, 1982
    Assignee: Sistig Corporation
    Inventor: Franz J. Schmid