Outer shuttle of sewing machine

An outer shuttle of a sewing machine, which accommodates an inner shuttle that grabs an upper thread and accommodates a bobbin around which a lower thread is wound, the outer shuttle comprising:

• a gear shaft which has a driven gear connected to a driving gear, provided on a lower shaft, which is a driving source of the outer shuttle that is rotatably supported in the sewing machine, and which also has a shaft support hole formed aligned with an axial center of the driven gear;
• a shuttle body to which the gear shaft is press-fitted and fixed at the center of rotation of a press-fit receiving hole formed in a bottom portion thereof;
• and
• a shuttle supporting shaft which is inserted into and therethrough the shaft support hole of the gear shaft of the shuttle body to support rotation of the shuttle body, wherein
• a plurality of ridge-shaped portions is formed on an inner circumference of the shaft support hole so as to correspond to a press-fitting depth of the gear shaft.