Juki Corporation

Juji Corporation

Kiyoshi Matsuzawa

Fumio Wada

Minoru Hayashi

Hiroyuki Kotaki

Naofumi Fukuba

Yuichi Sukegawa

There are provided an upper shaft clutch mechanism a bobbin including a slit , a horizontal holder including an inner holder and a blade tip , a bobbin driving member , bobbin driving member moving means for moving the bobbin driving member to freely advance or retreat between two positions having a separating position and a connecting position, a thread holding and catching member including an upper thread holding portion , an upper thread engaging portion and a thread position regulating portion which are always set in a retreat position and are set in an entry position during a thread winding operation, thread holding and catching member moving means for moving the thread holding and catching member to freely advance or retreat between two positions having a retreat position and an entry position, and a thread winding operation control portion for controlling the operation of each portion during the thread winding operation.

Lower thread winding device

In an embroidery sewing machine having a lower thread winding device, when the non-lower thread state of the bobbin is detected by a residual amount sensor, a sewing machine motor is stopped to detect and recognize the size of the embroidering frame of an embroidering device by means of a frame size sensor and the embroidering frame is moved corresponding to the size to position the corner of a workpiece held in the embroidering frame under a needle. Then, an extra sewing operation is carried out over the corner to consume the lower thread remaining in the bobbin, and subsequently, it is decided whether or not the embroidering frame is moved by a distance required for completely extracting the lower thread from the bobbin (an amount of the residual lower thread is detected when the non-thread state is detected by the residual amount sensor). If the distance is insufficient, the destination of the embroidering frame is updated to repeat the extra sewing operation over the next corner of the workpiece S, thereby completely extracting the lower thread from the bobbin.

Embroidery sewing machine with lower thread winding device

Growing community of inventors

Chofu, Japan

Kiyoshi Matsuzawa