Abstract: A position indicating unit of sewing machines, and more particularly a position indicator installed in sewing machines, having a magnet, pole plates, Hall effect ICs, amplifying actuating circuits and a visual signaling device to indicate and monitor the operation of automatic needle position control system, and to cause a conventional needle braking mechanism or the like to stop the sewing machine at a given position.

Abstract: This invention relates to a clutch and brake device, more particularly to such a device that the coupling winding fixed onto the supporting means extends within the rim groove of the flywheel-and-clutch member, having a clearance in between the coupling winding and the flywheel-and-clutch member, and two sets of brake winding are installed in the brake member; having the features that by selecting either the coupling winding or the brake winding to be energized either the clutch disc or the brake disc is moved toward the coupling or the braking position to make friction engagement with the clutch member or the brake member to drive or to brake.