Abstract: A linear displacement detecting structure 10 has a contact area 24 where a part of the periphery of a shaft 16 indirectly fits in/contacts a shaft hole member 14 through balls 34, and a non-contact area 26 where the other part of the periphery is spaced apart from the shaft hole member 14. A scale 20 is disposed in the non-contact area 26, and a sensor 22 is disposed in the vicinity of the shaft base member 14.

Abstract: A needle thread changing device of a sewing machine, comprises: a first thread end holding section for holding thread end portions of plurality threads respectively drawn from a plurality of spools; a thread cutting section for cutting a thread being currently used while selectively drawn from the first thread end holding section; a second thread end holding section for holding an end portion of the thread of a needle side cut by the thread cutting section; a thread selecting section for selecting a changing thread from the plurality of threads held by the first thread end holding section; a thread end portion moving section for moving an end portion of the thread selected by the thread selecting section to a predetermined knotting position; and a knotting section for connecting the end portion of the thread thus selected to the end portion of the thread currently used held by the second thread end holding section at the knotting position after the thread thus selected has been moved to the predetermined knot

Abstract: A method and an apparatus for picking up a fabric workpiece by applying vacuum provides two vacuum sensors; one for a sample fabric and the other for a fabric workpiece to be picked up. Where the apparatus has picked up incorrect number of sheets, the two vacuum sensors will output different voltages and the values are converted from analog to digital and input to a comparator. Thus, in such a case, the comparator outputs particular signals to stop the picking-up action of the apparatus.

Abstract: The disclosed method and apparatus for setting a workpiece correctly on a skirt-zipper sewing machine provides a pair of pressing plates which are positioned at the center of a zipper when the plates are lowered and which press the material of the workpiece and the zipper to be sewed to it.Each pressing plate works as a guide to set the to-be-sewn section of the workpiece at the center line of the zipper. The plates are then raised and again lowered to press the workpiece so that shrink marks that occur in bias curved sections of the workpiece are stretched. In this manner, a zipper is sewed to the workpice without shrink marks.

Abstract: An alignment apparatus for setting a workpiece on a zipper sewing machine including a workpiece presser arm having surface projections which contact with internal micro-switches of a ring-like side plate which receives and faces the workpiece presser unit. The presence or absence of the surface projections in relation to the micro-switches creates variations in signals which are effective to select the required sewing pattern.

Abstract: An apparatus installed on a sewing machine for automatically turning over a garment flap during zipper stitching first descends such that a flap lever which turns the flap over is positioned closely beside the flap, and second the flap lever is rotated laterally. The flap lever securely turns over the flap without being lifted unnecessarily higher, and the initial position of the flap lever is high enough to not obstruct the setting work of workpiece. A pneumatic cylinder successively causes the above described actions.

Abstract: The disclosed method and apparatus for setting a workpiece correctly on a skirt-zipper sewing machine provides a pair of pressing plates which are positioned at the center of a zipper when the plates are lowered and which press the material of the workpiece and the zipper to be sewed to it.Each pressing plate works as a guide to set the to-be-sewn section of the workpiece at the center line of the zipper. The plates are then rasied and again lowered to press the workpiece so that shrink marks that occur in bias curved sections of the workpiece are stretched. In this manner, a zipper is sewed to the workpiece without shrink marks.

Abstract: A method and apparatus for attaching a zipper when a zipper is attached to a garment which provides a flap to cover the zipper attached thereto, conducted such that a "perfect stitch" line appears on the garment surface and a "hitch stitch" line is covered by the garment flap. Thereby, the quality of stitching work is not degraded.

Abstract: An apparatus for setting a zipper and a front cloth to sew in correct position providing a pair of set-plates which perform three dimensional motion: vertical swing to clamp a workpiece and horizontal swing to form a "V" shape to receive a slitted front cloth and forming parallel lines to locate the zipper and the front cloth in the correct position. The motion of the set-plates is driven by air cylinders actuated by a pedal switch.