| 摘要 |
<p>An upper portion bears the needle with trailing thread and is the part by which the needle and thread can be inserted through the fabric in a fabric-supporting lower portion. The upper portion is laterally movable according to the buttonhole spacing. In the lower portion is a reciprocable double-sided thread-lifting hook which moves between two end positions outside the two entry positions of the needle. The hook moves between needle and thread when the needle is inserted in the lower portion, so as to retain a thread loop when the needle is withdrawn and present it in a position for passage of the needle on re-entry of the latter.</p> |
