Patent ID: 8661997

Claim:
A method for forming single-thread locked handstitches, comprising the steps of: (a) contacting circumferentially on an open eye needle and tightening a thread which is drawn out from a thread exit by rocking the thread exit of a bobbin case which houses a bobbin that the thread which is incorporated in a bobbin casing is wound by rocking the bobbin casing which is loaded in the rotative outer rotary hook of a rotary hook positioned under a throat plate by the time the open eye needle which is provided with the thread capturing open eye laterally and performs a linear reciprocating motion vertically comes down from an upper dead center, pierces a fabric workpiece which is placed on the throat plate, and goes up from the brink of reaching a lower dead center in a first stroke, (b) capturing the thread which is contacted circumferentially on said open eye needle and is tightened by said thread capturing open eye when said open eye needle goes up from said lower dead center, (c) feeding said fabric workpiece with one stitch length while said open eye needle slips out from said fabric workpiece, goes up, and passes through the upper dead center in said first stroke, (d) scooping the thread which is captured by said thread capturing open eye by a loop-taker point of said rotative outer rotary hook, and releasing the captured thread by the rotation of said rotary hook from said thread capturing open eye when said open eye needle comes down from the upper dead center, pierces said fabric workpiece, and goes up from the lower dead center in a second stroke, (e) guiding in the thread which is scooped by the loop-taker point of said rotary hook and released by the further rotation of said rotary hook to said rotary hook, interlacing the thread to the thread which is wound in said bobbin, and tightening the thread which guides out from said rotary hook, (f) feeding said fabric workpiece with one inter-stitch pitch while the open eye needle slips out from said fabric workpiece, goes up, and passes through the upper dead center in said second stroke, and (g) forming a handstitch on a front surface and a locked stitch on a back surface of said fabric workpiece by repeating the steps from said (a) to (f).