| 摘要 |
The present invention comprises a cap body (510) that is coupled with a central shaft of a bobbin (400), has a central portion provided with a mounting column passing hole (511) through which a bobbin mounting column (330) of a hook body passes, and has an end portion on one side of an outer circumferential surface provided with a lower thread discharge notch groove (512) which is cut to be a path of a lower thread unwound from the bobbin (400); a separation prevention piece (520) that is coupled in a slidable manner with a front surface of the cap body (510) and has a central portion where a locking hole (521) is formed to be engaged with a locking groove portion (331) formed on an outer circumferential surface of an end portion of the bobbin mounting column (330) while allowing the bobbin mounting column (330) to pass through; an elastic member (530) that is installed on the front surface of the cap body (510) and elastically supports the separation prevention piece (520) so that the locking hole (521) of the separation prevention piece (520) remains in a state of being engaged with the locking groove portion (331) of the bobbin mounting column (330); a cap removal lever (540) that is installed in a pivotable manner on a front surface of the separation prevention piece (520) and releases the engagement between the locking hole (521) and the locking groove portion (331) by pushing the separation prevention piece (520) to one side when the cap removal lever (540) pivots forward; a lower thread guided dam (550) that protrudes along a circumference of the locking hole (521) of the separation prevention piece (520) and guides the lower thread which comes off the lower thread discharge notch groove (512) of the cap body (510). |
