| 摘要 |
FIELD: sewing machines. ^ SUBSTANCE: the rotary motion of the upper shaft of the sewing machine is transformed to the reciprocating motion by means of a motion transmission mechanism. The edge of the cloth is cut by the upper cutting device, which operates in accordance with the up and down displacement, and by the lower cutting device, which operates in interaction with the upper cutting device. The upper cutting device is directed for sliding by the driving u it of the cutting device that is installed for turning on a frame. The motion transmission mechanism is coupled to the upper cutting device by means of a coupling. The coupling transmits to the upper cutting device during operation of the cutting device and turns the driving unit of the cutting device to the by-passing position and interrupts the transmission of power to the upper cutting device at the time when the cutting device is idle. ^ EFFECT: enhanced efficiency. ^ 9 cl, 16 dwg |
