PURPOSE: To fix automatically a reel to an accurate position even if the reel is set to an inaccurate position to a certain extent by providing a means operating to press the said reel to press onto a reel reference face to a latch at fixing the reel.

CONSTITUTION: A reel fixing device has a latch 5". Then, the latch 5" is spread externally to be larger than the inner diameter of a reel 6" at fixing and shrinked internally to be smaller than the reel inner diameter at release. Moreover, the latch position in the broadwise direction of reel is arranged to make a taper section contact the flange of the reel of a minimum thickness at fixing. Thus, even if the reel is set to an inaccurate position to a certain extent, the reel is fixed automatically to the accurate position.