Tension is created by leading the thread over a zigzag path with several sharp bends, these bends being in addition to those that are needed to carry the thread from the cop or bobbin to the outlet eye.
SEE OR SEARCH THIS CLASS, SUBCLASS:
214, and indented subclass.
SEE OR SEARCH CLASS
242, Winding, Tensioning, or Guiding,
541+, and 153 for a tensioning a running material.