Fluid coupling device

摘要

A thread bobbin holder device having improved sealing between shafts, and consequently less bearing wear. The bobbin holder device is constituted by a bobbin holder body with a bobbin fitted on the outer circumference thereof through a bobbin holder member. A piston controlling the amount of tension between the bobbin and the bobbin holder member is provided inside the bobbin holder body. A holder shaft and a second shaft are provided, both of which have a longitudinal throughhole formed therein. A support body rotatably supports the bobbin holder body. A shaft joint connects the holder shaft and the second shaft. A tubular elastic member is disposed in the shaft joint and is fitted into respective end portions of the holder shaft and the second shaft.