Patent ID: 7980188

Claim:
A cloth-holder frame transfer apparatus for a sewing machine which is usable with a cloth-holder frame, the apparatus comprising: a carriage detachably attachable to the cloth-holder frame holding workpiece cloth; a carriage driving mechanism including an actuator moving the carriage in two directions intersecting each other on a horizontal plane; an external force detector which detects an external force applied by an operator to the cloth-holder frame attached to the carriage; an assisting force output device which produces force assisting the movement of the cloth-holder frame by the external force; and a control device which controls the assisting force output device based on the external force detected by the external force detector, wherein: the carriage driving mechanism includes first and second direction movement actuators which are provided with first and second direction displacement sensors respectively; and the first and second direction movement actuators comprise respective stepping motors, and the first and second direction displacement sensors comprise respective rotary encoders.