Abstract: A method for preventing seam ravel of multi-thread chain stitches is provided. After normal sewing is terminated with a looper set in a forward movement state, a state in which a needle thread loop caught by the looper is subjected to position-holding at a position closer to a forward movement end of the looper than a descent position of a needle is maintained until the needle descends through the needle thread loop caught by the looper. Thereafter, the position-holding of the needle thread loop is released to permit a sewing action for at least one stitch, thereby allowing the needle thread loop to be self-looped with a needle thread held by the needle. This surely strongly prevents the seam ravel of multi-thread chain stitches formed by the single needle, irrespective of the dimension of tension applied to the needle thread and the looper thread.

Abstract: A thread hook and a looper thread holder are arranged on a rear side of a needle drop position of a sewing machine. When usual sewing is completed, the thread hook and the looper thread holder swing and move close to a looper. A hook part provided at a tip end of the thread hook holds a needle thread loop caught by the looper and positions it on an advance end side of the looper away from the needle drop position, and a thread receiving part provided at a tip end of the looper thread holder holds a looper thread extending from the looper to cloths and positions it on the front side away from the needle drop position. The sewing machine performs sewing for at least one stitch while maintaining positions of the needle thread loop and the looper thread.

Abstract: Disclosed is a two-needle sewing machine that improves strength in a convex curve part by bringing a pair of stitches close together when sewing an item. A two-needle sewing machine includes a bed part; a column part; an arm part; a needle shaft that is disposed on the leading part of the arm part; two sewing needles that are attached to the needle shaft; two horizontal hooks that catch the respective needle thread loops of the two sewing needles; and a conveyor member that conveys a material to be sewn in a direction approximately orthogonal to the bed part. On the two-needle sewing machine, the sewing needle, which is positioned in a location distant from the column part, is disposed closer to the conveyance side of the material to be sewn than the sewing needle that is positioned in a location closer to the column part.

Abstract: A flat seam construction made up of a number of sequentially formed stitches and formed on a portion of one or more stitchable materials is disclosed. Each stitch has two outer threads, formed into first and second outer thread loops, and at least one inner thread, formed into at least one inner thread loop. Each of the inner and outer thread loops transversely penetrate the one or more stitchable materials. Each of the inner and outer thread loops have a bight portion engaging a bottom surface of the one or more stitchable materials. At least one looper thread is formed on the bottom surface, and arranged such that, the at least one looper thread passes between the bottom surface and at least one of the bight portions. At least one decorative thread is visible on a top surface of the seam construction.

Abstract: A multiple needle sewing machine. The sewing machine includes a needle head, a first needle and a second needle both coupled to the head, a drive mechanism, a gripper shaft, and a first gripper hook and a second gripper hook both coupled to the gripper shaft. The drive mechanism is configured to translate the first needle together with the second needle, and to individually translate only one of the first needle or the second needle.

Abstract: A multi-needle quilting machine is provided with a common drive that drives the needles and loopers. It may also drive the presser foot assembly. In the illustrated embodiment, a drive motor drives a rotating drive shaft. The drive shaft has an off-center drive assembly connected to it that rocks a needle rocker shaft as well as looper rocker shafts, and also a presser foot shaft. The off-center drive includes a pair of eccentrics on the drive shaft at each side of the machine. Each eccentric oscillates a linkage plate that is fixed to a shaft such as the needle rocker shaft and is also linked to the looper rocker shafts and the presser foot shaft. The eccentric thereby reciprocates the needles and oscillates the loopers, as well as reciprocates the presser foot plate, in permanent synchronization.

Abstract: One embodiment of the present invention relates to a machine for sewing, embroidering, quilting and/or the like. Another embodiment of the present invention relates to a method for sewing, embroidering, quilting and/or the like. In one example, the present invention may be applied (e.g., as a machine and/or method) to a multi-needle machine or method. In another example, the present invention may provide for automatic lower (or bottom) thread cutting. In another example, the present invention may provide for automatic lower (or bottom) thread cutting by utilizing the phase (that is, movement phase) of a return of a looper (or hook) to cut the lower (or bottom) thread.

Abstract: A multi-thread single-line chain stitch line, consisting of at least three threads. This method provides for the formation of variable structures of stitches, based on varying sequences for the conjoining of several top threads, loaded to their individual needles, with several bottom threads, loaded to their individual loopers. The method suggests intertwining top threads between each other. The proposed stitch structure provides homogeneity of mechanical stresses in the stitch line, resulting in higher strength and durability. The machine to provide such stitch line comprises a revolver, bringing required needles to the operation point and intertwining threads during formation of the stitch line, and likewise comprising a revolver for bringing required loopers to the operation point. In one of the embodiments of the present invention, only three top threads are used, with the looper having no bottom thread loaded in it.

Abstract: To provide a seam of attractive appearance in which tightening force is increased and raveling are prevented drastically. A seam (1) is formed by two needles (11, 12) juxtaposed in the direction at substantially right angles to the sewing direction (T), and consists of a chain seam (10) formed by a needle thread (12) passed through one needle (11), and a lock seam (20) formed by a needle thread (22) passed through the other needle (21). The loop (13) of a needle thread forming the chain seam (10) is passed through the loop (23) of a needle thread forming the lock seam (20) before tightening of stitch is performed, and a loop of the needle thread forming the chain seam located on a downstream side in the sewing direction is passed through the loop of the needle thread forming the upstream chain seam.

Abstract: A multi-needle chain-stitch quilting machine and method of operation thereof are provided that imparts relative motion between the needles and the material that is controlled so as to pull needle thread tails from the needle side of the quilted material. The feature of controlling thread tails may be optional to provide selection of either a high speed mode of operation without thread tail control or a quality mode of operation with reduction or removal of needle thread tails from the face of the quilted material. Thread trimmers may be included at each needle location on the looper side of the material to cut both needle and looper threads.

Abstract: Looper section provided under a needle plate includes: a plurality of loopers arranged in an array along a curved movement path; and a movement mechanism for moving the plurality of loopers along the curved movement path to selectively position one of the plurality of loopers in a predetermined needle drop position. Chain-stitch sewing is performed by cooperation between the one looper selectively positioned in the needle drop position and a hooked needle. The looper section projects at its one end portion including the predetermined needle drop position, and a cylindrical sewing workpiece can be taken to and from the needle drop position via the one projecting end portion. The curved movement path is, for example, a U-shaped path.

Abstract: Apparatus for forming a high shear strength clay liner comprising two synthetic geotextiles surrounding a semihydrated layer of swellable clay. The apparatus includes two parallel needle bars each carrying a row of needles reciprocating in opposed directions and cooperating with a reciprocating needle plate having a plurality of parallel fingers and a looper bar with a plurality of parallel looper plates rocking on an axis to form loops which can be melted to form protruding knots.

Abstract: Multi-needle quilting knotted-stitch machine with lower stitching elements having rotating hooks, the machine comprising an inlet assembly for the controlled feed of the textile material (11) to be quilted, a stitching assembly including upper stitching elements (12) and lower stitching elements and an outlet assembly for the collection and possible measurement and cutting of the quilted product (19). The upper stitching elements including at least two parallel bars (13) arranged lengthwise and supporting, in a position separated lengthwise, the relative stitching needles (24), the lower stitching elements of rotating hooks (17) being organized in longitudinal rows mating with the position of the relative needle-carrier bar (13), the position of each needle (24) corresponding to the position of a respective rotating hook (17).

Abstract: A sewing machine includes two rods rotatably and slidably supported in the sewing machine and two lower loopers secured on the rods. A spindle is coupled to the rods by an eccentric and coupling members for rotating the rods and the lower loopers. One of the lower loopers may be moved axially together with one rod to which a pawl is rotatably supported, The pawl may be selectively engaging with the other rod for allowing the pawl to selectively moving the other rod axially and for allowing the lower loopers to perform two double chain stitchings.

Abstract: A multi-needle chain stitch sewing machine with a thread thread severing system and method thereof for cutting needle threads between two isolated stitched patterns of a fabric. The multi-needle sewing machine includes a plurality of loopers and respective needles, a thread severing strip located in close proximity and transversely across each looper, and eccentric guides connected to the thread severing strip for extending the thread severing strip to cut the needle threads and for retracting the thread severing strip so that the thread severing strip does not contact the needle threads during the stitching operation.

Abstract: A thread cutter for a chain stitch sewing machine which performs chain stitch sewing by cooperation of a needle driven up and down and a looper arranged under a needle plate, including: a movable knife arranged so that it can advance into or retract from a gap between a top surface of the looper and an under surface of the needle plate; a knife driving mechanism for advancing and retracting the movable knife; a stationary knife arranged under the needle plate for cutting a sewing thread in cooperation with the movable knife when the movable knife is retracted; and a thread holding plate for holding a cut end of the sewing thread on the side of the looper in a predetermined position by a further retracting operation of the movable knife after the sewing thread is cut and a drive unit for a multi-sewing machine.

Abstract: A mechanism and method for forming a facing seam at a relatively high rate that will insure that the cover thread is properly interwoven between each stitch of two parallel rows of stitches. The facing seam is formed by two needles and cooperating loopers for forming two parallel rows of stitches that are joined by a cover thread that lies on the upper surface of the work piece. The cover thread is controlled by a conventional spreader and a cover thread assist member. The cover thread assist member is formed from a lightweight hardened wire that is fixed to a mid portion of the conventional spreader.

Abstract: A stitch and mechanism for forming such a stitch including three needles and cooperating loopers for forming three parallel rows of stitches that are joined by a spreader thread that lies on the upper surface of the work piece. The spreader thread is configuration to be on both sides of the three needles such that it connects and covers the three parallel rows of stitches.

Abstract: There is provided a needle attachment position indicator device for use in a sewing machine of a type comprising a stitch pattern forming mechanism provided in a machine frame for permitting selection of one stitch pattern from a plurality of different stitch patterns, an actuator member disposed in the machine frame for permitting selection of the stitch pattern, an actuation mechanism disposed in the machine frame for setting the stitch pattern forming mechanism at selected stitch pattern in response to the selective actuation of the actuator member, and needle holding means having a plurality of needle attachment positions. The device includes an indicator member capable of indicating needle attachment position corresponding to the selected stitch pattern, in response to the selective actuation of the actuator member.

Abstract: An electronically controlled multi-needle quilting machine including linking cylinder arranged between an eccentric integral with a rotating spindle and a lever, to drive in an oscillating motion a number of loopers which, in combination with a number of corresponding needles, perform stiching operations by double chain stitches on a layered material interposed between said members, said linking cylinder comprising a pneumatic cylinder controlled to change the extension of its rod during the various operational steps, whereby the link length is changed and the loopers may reach a position in which, by being provided with a blade they perform a cutting operation on thread of respective needle.

Abstract: A sewing machine with a housing having a base over which the workpiece is movable and with a drive shaft is rotatable in the housing. A needle bar is provided having a plurality of needles and is connected to the drive shaft and moved upwardly and downwardly. A feed mechanism is provided for moving the workpiece. A looper support has a looper for each needle and is connected to the drive shaft for swinging movement. A loop spreader connecting rod has a loop spreader for each needle and is movable transversely to the movement of the needles. A spreader drive shaft is connected to the drive shaft and has a drive crank eccentric which is oscillated by the rotation of the spreader drive shaft. An eccentric arm carried by the crank eccentric is connected to a rocking shaft via a clamp lever and the rocking shaft is connected to a crank which is connected to the connecting rod which carries the spreaders.

Abstract: An overlock sewing machine with a looper-thread guide mechanism of this invention is characterized by thread guide passages that are provided in the front face of the sewing machine body, and that go from thread tension disks toward loopers. By feeding looper thread along the thread guide passages, the looper thread is easily guided from a thread supply source, through the tension disks and a takeup, toward the loopers. Thus, the loopers can be threaded easily, quickly, and precisely.

Abstract: A thread undercut attachment for use on multi-needle sewing machines uses a single piston actuated cutting blade which passes through the sewing area beneath the workpiece and above the loopers. To prevent the needles and loopers from becoming unthreaded or to prevent undue lengths of thread after cutting, apparatus is provided for creating a measured amount of slack in the threads leading to the needles and loopers, and then holding the threads firmly to prevent further payout of thread when the workpiece is pulled toward the operator.

Abstract: A thread tension control device for overedging sewing machines wherein each needle thread tension controller and each looper thread tension controller provide two springs designed to clamp two tension discs wherethrough a thread is passed. A slide plate, by its horizontal sliding motion, either causes the two springs to be active or causes one of the two springs to be released thereby obtaining either strong or weak thread tension. A workpiece end detector defines either an overedging process or thread chain forming process and sends a signal to actuate the horizontal sliding motion of the slide plate. Thus, the proper thread tensioning for each needle thread and each looper thread for either an overedging process or a thread chain forming process may be automatically adjusted.

Abstract: A looper throw out mechanism is provided for bodily moving sewing machine loopers from their normal operative position to a servicable position and back. The looper throw out mechanism includes a looper carrier pivotally arranged on the looper drive shaft, a fork like member attached to the looper carrier, a control disc disposed in operative combination with the fork like member for defining the angular displacement limits of the looper carrier, and a manually operated locking device for releasably securing the looper carrier to the looper drive shaft. When looper servicing is desired, the locking device is released by the operator permitting the looper carrier and the loopers to be pivoted to a serviceable position removed from their operative position.

Abstract: A sewing device for use in multi-needle sewing machine comprising a plurality of needles, presser feet, throat plates, feed dogs and loopers arranged in parallel with each other, and optionally a plurality of spreaders arranged in parallel with each other. Each needle holder on which each needle is set is supported on a needle bed in a manner slidable in the direction of the row of needles and is fixed to any slided position by tightening each set screw. Each interval between needles are changed by changing the fixing position of each needle holder. Each presser foot, throat plate, feed dog, looper and spreader are respectively held by the presser foot holder, throat plate holder, feed dog holder, looper holder and spreader holder in a slidable manner along the direction parallel with the row of needles, and are fixed to the required positions corresponding to each of changed needle interval.

Abstract: A device for stabilizing the needle thread loop in the area of the looper in sewing machines and, in particular, in sewing machines having a plurality of needles, is provided wherein a compressed air stream flows substantially transverse to the movement path of the part which contains the needle thread loop. Two compressed air nozzles are provided for each needle which are positioned at the side of the needle facing away from the needle thread loop in such a manner that the compressed air streams meet in the area of the needle thread loop.

Abstract: Multiple hem stitches are produced for joining a plurality of superimposed fabric materials along their edges by employing a sewing machine having a pair of vertically reciprocating needles each carrying a needle thread and a pair of loopers each carrying a looper thread. The first and second needle threads extend along the fabric edge and in parallel with each other on the upper face of the fabrics and penetrate through the fabrics to form a first and second needle thread loops on the underside of the fabrics. The first needle thread loop is distended laterally to the fabric edge by the first looper. The first looper thread encompasses the first needle thread at each penetration point and extends laterally on the upper face of the fabrics to form a first looper thread loop which is caught by the descending first needle to be interlocked with the first needle thread loop along the fabric edge.

Abstract: A sewing machine for simultaneously forming a plurality of spaced seams disposed in parallel relation. The machine includes a pair of spaced needle bars and needle clamps for supporting stitching needles. Adjacent each needle bar a presserfoot bar is provided for supporting separate presserfoots on their lower ends. Below each presserfoot there is a cooperating feed dog and below each feed dog a separate looper for controlling the lower threads during the formation of chain stitches. To form the stitches simultaneously, all of the machine's stitching instrumentalities, including the stitching needles, presserfeet, feed dogs and loopers, are operatively interconnected so that their movements occur at the same time.

Abstract: A device for interrupting the formation of stitches in a sewing machine having at least two needles and a looper for each needle which are arranged to be actuated in tandem. The needles are phased to perform their functions simultaneously with a first having an elongated thread opening, and the second a conventional opening. The first needles' looper is slightly elevated and if no lack of phasing exists between the needles and their loopers, the elevated looper will cooperate with its needle adjacent the upper end of the thread hole and the other looper cooperates with its needle in a conventional manner. Should there be a lack of phasing, the elevated looper cooperates with its needle midway between the length of the thread hole which causes the other looper to pass beneath the hole of its needle thus interrupting the formation of stitches by the latter needle.

Abstract: A separate pair of tensioning elements for the needle thread and for the looper thread in sewing machines adapted to form seams of stitches on a succession of workpieces which are advanced in the direction of sewing by a main transport device and an auxiliary transport device disposed in spaced relation to the latter. A sensing device and control device is operatively associated with the tensioning elements and tension is caused to be applied by each pair of elements on their respective thread when a workpiece is present in the main transport device. Upon advance of the workpiece to a point where its advance is effected solely by the auxiliary transport device, the tension imposed by one of each pair of elements is automatically released.

Abstract: A needleplate for a two-needle sewing machine of the type for simultaneously forming a straight stitch chain and an over cast stitch chain. The plate is provided with guide surfaces which interconnect the needle holes in the plate and a device for increasing the quantity of thread normally used by the looper associated with the needle for forming the straight stitch chain. At the completion of a sewing cycle the combination of the guide surfaces and excess looper thread permit the straight stitch chains to be moved toward and in alignment with the overcast stitch chain so that they will be incorporated together in the initial stitches formed in the following workpiece.