INTERMITTENT DRIVING DEVICE FOR SEWING MACHINES

摘要

A sewing machine motor is connected to a drive wheel which can be connected via a clutch to a drive shaft that vertically reciprocates the sewing-machine needle. A cam on the shaft and a stopper on the housing are displaceable between an operative position engageable with each other for stopping rotation of the shaft in a predetermined angular position corresponding to the up position of the needle and an inoperative position unengageable with each other. A cam is provided for displacing the control element of the clutch from an engaged to a disengaged clutch position on engagement of the stopper in its operative position with the cam so that the shaft can be arrested in a predetermined angular position and is substantially simultaneously rotationally uncoupled from the wheel. Pawls engageable with a cam carried on the shaft serve to substantially simultaneously displace the clutch control element into the engaged position and the stopper into the inoperative position for starting-up of the sewing machine again after one intermittent-drive cycle.