Bobbin

1. A bobbin in which a needle attached to a needle bar, which moves up and down, and a horizontal shuttle supply in cooperation with each other a bobbin thread for forming a stitch, the bobbin comprising:

a bobbin main body including flanges at both ends of a bobbin winder spindle for winding the bobbin thread; and

an outer flange attached to one of the flanges of the bobbin main body,

wherein a gap in which a thread end of the bobbin thread is housed is provided between the outer flange and the flange of the bobbin main body, and

wherein a thread come-off preventing unit that prevents the housed thread end of the bobbin thread from coming off the gap is provided in the gap.

2. A bobbin in which a needle attached to a needle bar, which moves up and down, and a horizontal shuttle supply in cooperation with each other a bobbin thread for forming a stitch, the bobbin comprising:

a bobbin main body including flanges at both ends of a bobbin winder spindle for winding the bobbin thread; and

an outer flange attached to one of the flanges of the bobbin main body, wherein

a gap in which a thread end of the bobbin thread is housed is provided between the outer flange and the flange of the bobbin main body,

wherein a thread come-off preventing unit that prevents the housed thread end of the bobbin thread from coming off the gap is provided in the gap, and

wherein the thread come-off preventing unit is formed as a protrusion section that projects from at least one of the outer flange and the flange of the bobbin main body to face the other one of the outer flange and the flange of the bobbin main body.

3. The bobbin according to claim 2 , wherein the protrusion section is formed in the outer flange.

4. The bobbin according to claim 2 , wherein the protrusion section is formed in the flange of the bobbin main body.

5. The bobbin according to claim 2 , wherein protrusion sections are formed in the flange of the bobbin main body and the outer flange respectively.