| 摘要 |
The invention relates to a sewing machine (100) configured to avoid a hitch stitch. The sewing machine (100) includes a rotation base (43) rotatable about a center line (C) of a needle bar (12), a rotation drive motor (463), and a differential transmission mechanism (40) including an input shaft (41) coupled to a sewing machine motor (21) and an output shaft (42) coupled to a shuttle (13). The differential transmission mechanism (40, 40A) is configured such that a phase difference between the input shaft (41) and the output shaft (42) is adjustable. The input shaft (41) and the output shaft (42) are aligned on the center line (C) of the needle bar (12). The differential transmission mechanism (40) includes a support frame (441) rotatable around the input shaft (41) and the output shaft (42), a transmission member (445) rotatably supported by the support frame (441) and transmits a rotating force between the input shaft (41) and the output shaft (42) such that a rotation direction is reversed, a first driven member (461) provided on the support frame (441), a second driven member (462) provided on the rotation base (43), a first driver member (464) providing a rotating force to the first driven member (461), and a second driver member (465) providing a rotating force to the second driven member (462). An amount of a rotation transmission from the first driver member (464) to the first driven member (461) is half an amount of a rotation transmission from the second driver member (465) to the second driven member (462). The first driver member (464) and the second driver member (465) are provided on the same shaft in a fixed manner such that they rotate simultaneously. |
