| 摘要 |
A rotary thread take-up lever for acting on an upper thread in a sewing machine, comprising: a base portion which is continuously rotatable around a predetermined axis in one direction; and an arm extending outwardly from the base portion with respect to the axis, the arm including a front edge facing in the direction of rotation of the thread take-up lever and a rear edge facing in the direction opposite to the direction of rotation of the thread take-up lever. The front edge has a thread holding point, wherein the upper thread being lifted by the thread take-up lever is slid on the front edge. The rear edge has a thread holding point, wherein the upper thread being supplied from the thread take-up lever is slid on the rear edge. When the upper thread is supplied maximumly, the upper thread is held by the thread holding points of the front and rear edges, respectively. The radius of rotation of the thread holding point on the rear edge is smaller than the radius of rotation of the thread holding point on the front edge.
|
