PURPOSE: To increase the critical speed of a bobbin holder by decreasing the radial thickness of an elastic ring as far as possible, to dispense with the stop of machine and to improve the operability of the ring by eliminating the creep problem of the elastic ring.

CONSTITUTION: A ring-shaped spring member 30, a pair of rigid rings 38 fixed to both side faces of the spring member 30 and elastic rings 3a-3d made of a rubber material 39 placed between the rigid rings and on the inner and outer circumferences of the spring member are loosely inserted between a cylindrical bobbin 23 and a rotary cylinder 2 for inserting the bobbin. Each rigid ring 38 is compressed from both side faces of the elastic ring to radially expand the ring-shaped spring member 30 and hold the bobbin by closely contacting the rubber material 39 to the inner circumference of the bobbin 23.