Abstract: A thread end holding device for a sewing machine comprises a needle thread catching puller which is swingably supported on the side of a sewing machine arm and is driven to swing between a thread catching position and a home position, and which comprises a hook portion at the tip end thereof for catching a needle thread extending from a needle when said needle thread catching puller is at its thread catching position and holds the needle thread at its home position and first and a second holding members which are respectively mounted on the side of the sewing machine arm and is disengaged from the both clamping portions when the needle thread catching puller is at its thread catching position and enters a gap between the both clamping portions at the hook portion thereof so as to elastically clamp the end of the needle thread between the clamping portions when the needle thread catching puller is at its home position.

Abstract: A needle bar thread guide device for a sewing machine comprises a needle bar thread guide which is fixed to the lower end portion of the needle bar of the sewing machine and has a thread retaining portion therein for guiding the needle thread and an auxiliary thread guide which is mounted on the needle bar above the needle bar thread guide in such a way as to be adjustable in its vertical position and has a threading hole therein for passing the needle thread therethrough so as to apply a frictional force to the needle thread by contacting the needle thread at the rim thereof, characterized in that the retaining point of the thread retaining portion and the contact point of the threading hole are shifted from each other in a plan view.

Abstract: A thread end disposal unit in a thread cutting sewing machine has a thread end suction unit including a first suction tube having an open end positioned at the length of the starting end of a needle thread held by a thread end holder. A second suction tube is connected at a base end thereof to a base of the first suction tube via a suction device generating negative pressure for allowing the first suction tube to suck cut lengths of the needle thread. The device includes a Venturi-tube and an air compressor and a container storing the cut lengths as waste thread.

Abstract: The bottom plate of a cloth presser supporter is pivotally mounted on a lower end of the supporter adjacent a rear end of the plate. The plate has an L shaped slot, one slot leg being a needle location groove, the other slot leg being a needle thread guide. The plate has a knife receiving groove with a knife mounted therein. A thread holder holds the end of a thread vertically above the plate so that the thread when extended between the held thread end and the first zigzag stitch of the thread does not extend over a corner defined by the intersection of the side wall of one slot leg with the corresponding side wall of the other slot leg.

Abstract: A method of producing polycarbonate powder comprises continuously mixing and kneading a polycarbonate solution while heating same, the kneading being accomplished by producing a limited "to and fro" movement of the polycarbonate solution with the aid of a set of spiral blades mounted on rotating shafts in an elongated barrel.

Abstract: A heat resistant and impact resistant polycarbonate having a narrow distribution of molecular weight is continuously produced by reacting chloroformate ester, prepared in advance by reacting alkaline solution of dioxy compound in a turbulent flow of the two solutions while cooling and subsequently reacting the mixture concurrently in a laminar flow after the viscosity of the mixture has become significant.