A sewing machine includes a controller and a thread cutter which cuts an upper thread passed through a sewing needle and which has a fixed knife, a moving knife, and a driving source to drive the moving knife. The moving knife cuts the upper thread by guiding the upper thread. The moving knife has a through-hole into which the sewing needle is loosely insertable and includes a thread cutting portion in an inner edge portion of the through-hole. By controlling the driving source, the controller makes a stitch point of a first stitch of the sewing needle with respect to the through-hole of the moving knife, and moves the moving knife to a position where the fixed knife and the moving knife cut a sewing start end portion of the upper thread after a stitch point of a second stitch of the sewing needle.

The present invention relates to a structure for fastening composite structures, and more particularly, to a sewing machine for stitching composite materials which is capable of automatically and continuously stitching the composite structures by using a high-rigidity fiber in order to laminate and join the composite materials. The sewing machine for stitching composite materials according to the present invention automatically and continuously performs a stitching operation for joining composite materials by using a high-rigidity composite fiber for joining the composite materials, and as a result, it is possible to reduce process time for joining the composite materials and improve productivity.

The present invention relates to a structure for fastening composite structures, and more particularly, to a sewing machine for stitching composite materials which is capable of automatically and continuously stitching the composite structures by using a high-rigidity fiber in order to laminate and join the composite materials. The sewing machine for stitching composite materials according to the present invention automatically and continuously performs a stitching operation for joining composite materials by using a high-rigidity composite fiber for joining the composite materials, and as a result, it is possible to reduce process time for joining the composite materials and improve productivity.

A sewing machine includes a needle plate, a feed dog configured to move a workpiece, a vertical drive mechanism configured to vertically drive the feed dog, a switch mechanism, a cutting mechanism, and an actuator. The switch mechanism is configured to switch from an active state where the feed dog is driven, by the vertical drive mechanism, above and below an upper surface of the needle plate to an inactive state where an upper surface of the feed dog is maintained below the upper surface of the needle plate. The cutting mechanism includes a blade configured to cut a thread at a position below the needle plate. The actuator is configured to commonly drive the switch mechanism and the cutting mechanism.

A sewing machine includes a needle plate, a feed dog configured to move a workpiece, a vertical drive mechanism configured to vertically drive the feed dog, a switch mechanism, a cutting mechanism, and an actuator. The switch mechanism is configured to switch from an active state where the feed dog is driven, by the vertical drive mechanism, above and below an upper surface of the needle plate to an inactive state where an upper surface of the feed dog is maintained below the upper surface of the needle plate. The cutting mechanism includes a blade configured to cut a thread at a position below the needle plate. The actuator is configured to commonly drive the switch mechanism and the cutting mechanism.

A sewing or looping device for closing a tubular knitted article includes a body, two needles, a yarn support, and a cutting unit; the body has two spaced bases, the two needles are pivotally connected to the first base, respectively, and pivoting movement paths of the two needles are orthogonal to each other, the yarn support has a first section adjustably disposed on one of the bases, and a second section extending along an axial direction. The cutting unit is pivotally connected to the base where the yarn support is located. A cutting direction of the cutting unit is parallel to the axial direction, and the sewing chain stitch is pulled to the cutting point by the hook member and cut thereat. The sewing chain stitch assumes a tensioned state when being pulled, which in turn allows the sewing chain stitch to be cut more reliably and easily.

A sewing machine includes a controller and a thread cutter which cuts an upper thread passed through a sewing needle and which has a fixed knife, a moving knife, and a driving source to drive the moving knife. The moving knife cuts the upper thread by guiding the upper thread. The moving knife has a through-hole into which the sewing needle is loosely insertable and includes a thread cutting portion in an inner edge portion of the through-hole. By controlling the driving source, the controller makes a stitch point of a first stitch of the sewing needle with respect to the through-hole of the moving knife, and moves the moving knife to a position where the fixed knife and the moving knife cut a sewing start end portion of the upper thread after a stitch point of a second stitch of the sewing needle.

A sewing machine includes a controller and a thread cutter which cuts an upper thread passed through a sewing needle and which has a fixed knife, a moving knife, and a driving source to drive the moving knife. The moving knife cuts the upper thread by guiding the upper thread. The moving knife has a through-hole into which the sewing needle is loosely insertable and includes a thread cutting portion in an inner edge portion of the through-hole. By controlling the driving source, the controller makes a stitch point of a first stitch of the sewing needle with respect to the through-hole of the moving knife, and moves the moving knife to a position where the fixed knife and the moving knife cut a sewing start end portion of the upper thread after a stitch point of a second stitch of the sewing needle.

A chain-off thread cutter for cutting a chain-off thread formed by a sewing machine. The chain-off thread cutter including: a fixed blade; a movable blade that moves toward and away from the fixed blade; a driving unit that drives the movable blade to move the movable blade; a foreign matter detector that detects foreign matter present in a track of the movable blade; and a control unit that stops the driving unit when the foreign matter is detected by the foreign matter detector.

A sewing machine and the method for closing open end of tubular knitted articles. The sewing machine is configured to knit and close the open end of a tubular knitted article, comprising a frame, a knitting head and a thread cutter. The knitting head and the thread cutter are disposed rotatably on the frame, the knitting head has a needle, a needle-shaped hook and a knot making peg to form thread knots, and the thread cutter is configured to cut the knitting thread, wherein the thread cutter is configured in a fashion of making a relative movement to the knitting head.