PURPOSE: To dispense with a motor for tension imparting by constituting a tension imparting mechanism suitable for giving a tension to the fiber of a linear product in weaving so that a bobbin capable of winding the linear product is traveled and rotated along an inclined plate.

CONSTITUTION: A tension imparting mechanism is formed of a bobbin 1 having a saw-tooth irregular part (a) on its collar part; and an inclined plate 2 inclined at about 60° which has a slant face part (b) subjected to the irregular treatment geared with the irregular part (a) and a bobbin reserving part (c) rotatable in about the position of the bobbin as it is smooth and never geared with the irregular part (a) of the bobbin collar part. In the state where the bobbin 1 is placed on the holding part (c), and a linear product 3 wound on the bobbin 1 is drawn in the direction (g), the tension according to the dead weight of the bobbin 1 is given to the liner product 3. When the linear product 3 is loosened, the bobbin 1 is lowered on the slant face part (b) by the dead weight according to the loosening degree of the linear product 3, and the tension is given through the gearing with the irregular part (a).