Abstract: A sewing machine includes a sewing-machine motor that drives, through an upper shaft and a lower shaft, a thread take-up lever, a needle bar, and a shuttle in conjunction one another. In addition, the sewing machine includes a stepping motor different from the sewing-machine motor. A bobbin-thread supply member is driven by drive power from the stepping motor, and applies tension to a bobbin thread in accordance with the drive timing of the stepping motor and the drive amount of the stepping motor. The drive timing of the stepping motor is variable in accordance with a sewing condition.

Abstract: A sewing machine of an “overlook” “cut-and-sew” type for sewing together at least two flaps (3a, 3b) of textile that are overlapping and belonging to one or more textile articles, comprising at least a needle plate (2) suitable for supporting at least two overlapping flaps (3a, 3b) of textile of one or more textile articles which are sliding for forming sewing stitches (10a, 10b, 10c), the needle plate (2) being provided with through-openings defining respective seatings (4) for passage of sewing needles (5) and at least a lateral appendage (6) defining a sliding line (7) for the sewing stitches (10a, 10b, 10c); a lower crochet hook (14); an upper crochet hook (15); and at least a sewing needle bearing device (11) with at least three sewing needles (5) mounted on the device (11), reciprocally flanked, aligned to one another and supplied with respective sewing threads (10), and being suitable for passing through the seatings (4) of the needle plate (2) for sewing the over-lapping flaps (3a, 3b) of textile, the

Abstract: A thread routing mechanism for needle-switchable type sewing machine is installed on a needle bar switching mechanism of the sewing machine, and includes a thread take-up lever, a cylindrical needle bar case and a plurality of threads. The thread take-up lever includes a sway control end and a thread take-up end having thread holes. The cylindrical needle bar case has a rotation axis and a plurality of spaced needle bar holes, and internally defines a hollow space. The needle bar holes are equally distant from the rotation axis, and each receives a needle bar therein. The needle bars respectively carry a needle having an eye formed thereon. The threads are separately routed through a thread course defined by the thread holes, the hollow space and the needle eyes, such that the length of the threads in the thread course maintains same without being affected by a needle bar switching operation.

Abstract: There is provided a needle thread tension controller that can control a magnitude of tension on a needle thread for each stitch, that can draw the needle thread with a slim chance of occurrence of a thread break, that easily, accurately detects occurrence of the thread break when the thread break has occurred, and that does not cause any excess or deficiency of a quantity of accumulated thread, which would otherwise be caused by drawing a needle thread. There are provided an upstream grip section 40 and a downstream grip section 60 for gripping a needle thread and a turning section 80 for turning the needle thread. In a torque control zone, rotating force is imparted to a turning arm in accordance with a torque value.

Abstract: A material feeding device includes material wrapped around a spool, the spool rotating around an axis. A material feeding mechanism feeds the material in a feeding direction, thereby unraveling the material from the spool. A force deflection device is arranged between the spool and the material feeding mechanism, and is connected to the material. The force deflection device is configured to as to deform physically when the material feeding mechanism applies an initial feeding force to the material.

Abstract: Pressurized gas for carrying looper thread by gas is generated by gas supply pump operated by changing over a sewing-machine motor, which drives stitch forming device, looper threading is performed through loopers by one-touch operation. Gas carrying threading device of sewing machine, comprising: looper thread introduction mechanism inserts looper thread guided to loopers; hollow looper thread guide extends from looper thread introduction mechanism to looper thread inlets and has looper thread guide outlets; gas supply pump for performing looper threading by carrying looper thread by gas from looper thread introduction area through hollow looper thread guide to looper thread loop-taker point outlets; clutch for transmitting power from sewing machine motor M to drive shaft which drives stitch forming device including loopers at time of stitch formation or to gas supply pump at time of looper threading.

Abstract: A multi-needle sewing machine is disclosed that includes a needle-bar case that supports needle bars; a needle-bar case transfer mechanism that transfers the needle-bar case to place a predetermined needle bar to a needle drop position; a thread guide member that is movable up and down, the thread guide member being provided with thread guide sections spaced by a predetermined distance and that guide a plurality of threads; a plurality of thread inlets that are provided at the needle-bar case, each thread inlet being uniquely associated with one of the thread guide sections and that introduces the threads guided by the thread guide sections toward the needle bars; and a lifting/lowering mechanism that moves the thread guide member up and down during transfer of the needle-bar ease and the thread inlets such that the thread guide sections and the associated thread inlets maintain a constant distance therebetween.

Abstract: A sewing machine includes upper and lower beams. A thread hooking mechanism is mounted in the lower beam. A needle plate base is mounted to an end of the lower beam. A transmission shaft rotatably extends in the lower beam and has an end extending into the needle plate base. The transmission shaft can be driven by a power source. A driving device is mounted to the end of the lower beam and includes a transmission shaft rotatably received in the needle base plate, a transmission gear fixed on the end of the transmission shaft, a driven shaft rotatably received in the needle base plate and having an end coupled to the thread hooking mechanism, and a driven gear fixed on the driven shaft and connected to the transmission gear, with the driven shaft and the thread hooking mechanism rotating at a speed higher than the transmission shaft.

Abstract: A sewing machine includes a plurality of bobbins, thread guiding device, thread selecting device, a needle having an eye, a thread take-up lever having a thread receiving hole, thread taking-out device, movable thread hooking device, and thread letting-through device. The thread guiding device delivers a plurality of threads from the bobbins. The thread selecting device selects one of the threads. The thread taking-out device brings the selected thread adjacent to the eye of the thread. Simultaneously with the thread taking-out action of the thread taking-out device, the movable thread hooking device and the thread letting-through device co-operatively let the selected thread, being disposed between the thread take-up lever and the needle, pass through the thread receiving hole of the thread take-up lever via an opening of the thread receiving hole, and let the leading end of the selected thread pass through the eye of the needle.

Abstract: The present invention provides a looper thread paying-out apparatus of sewing machine in which apparatus a variation of paying-out tension of the thread from a bobbin does not affect a seam.Just before a thread tensioner of a looper system which feeds a looper thread from a bobbin of sewing machine through to thread tensioner, an auxiliary paying-out apparatus is provided for paying out previously a portion of thread for a length of one stitch corresponding to an amount of horizontal cloth feed and feeding that portion into the thread tensioner at zero tension.

Abstract: The feed dog (17) for the fabric in a sewing machine is provided with a spring-wire (21) bent and passing through a hole of a support (23). When the feed dog (17) is in its upper position, the support (23) abuts the plate (18), which lowers the end (24) of the wire (21) so as to exert a tension on the lower thread (8) of the seam. When the feed dog is lowered, the wire (21) resumes its normal position, namely its end (24) is displaced upwardly with respect to the dog (17) and the thread (8) is thus relaxed.

Abstract: A thread securing device in a sewing machine wherein an upper thread located along a thread guiding path is caught during the travel of a thread take-up member to effect automatic hooking of the thread thereto. The thread securing device includes a thread saving member capable of saving an amount of the upper thread corresponding to a predetermined amount of the upper thread to be taken up by the thread take-up member during its movement from a thread loosening position to a thread take-up position, and capable of feeding the saved amount of the upper thread freely in accordance with the thread take-up movement of the thread take-up member; and an actuating member adapted to catch the upper thread extending along the thread guiding path when the thread take-up member is not holding the upper thread and then supply an amount of the upper thread corresponding to the predetermined amount, to the thread saving member.

Abstract: An overlock sewing machine wherein a thread which breaks between the shuttle and the looping discs is allowed to bypass the loop stripping device and is advanced by the discs toward and against the cutting edge of a knife provided on one leg of the U-shaped thread guide which confines the looping discs. This prevents the discs from convoluting the broken thread onto the shaft which drives the discs.

Abstract: An apparatus for feeding thread for a sewing machine comprising a thread feeding system for guiding the thread (14) from a spool (13) to a take-up lever (2) of the sewing machine (A). The thread feeding device is comprised of a pressure roller (10) and a feed roller (8) driven by a motor, an encoding device (17) installed on the main drive shaft of the sewing machine, an encoder (8a) for measuring the length of the thread fed, and a thread holding device (11), whereby when the encoding device (17) gives the signal to the thread holding device to release the thread, the thread feeding device feeds the thread for completing one full stitch, and the encoder (8a) actuates the thread holding device (11) to hold the thread during the stitching.

Abstract: A thread pull-out mechanism for sewing machines, which pulls out a predetermined amount of the needle thread from the thread supply spool by means of an operating member interlocked with the take-up lever of the sewing machine. A turn-over member for turning over the direction of supply of the needle thread is disposed in a threading path between the thread supply spool and the tension regulating mechanism of the sewing machine to check backward movement of the needle thread in pulling out the needle thread from the thread supply spool. During the thread take-up motion of the take-up lever of the thread take-up mechanism, the needle thread pulled out from the thread supply spool is slackened so that the turn-over member will not exert a significant resistance to the needle thread when the take-up lever pulls the needle thread previously pulled out from the thread supply spool. Thus, the needle thread is pulled by the take-up lever smoothly as the take-up lever is moved upward for thread take-up motion.

Abstract: There is a zigzag sewing machine provided with a horizontal rotary loop taker device which is restrained with respect to the rotation direction, and holds therein a bobbin carrier horizontally attached, and is supplied with a lower threads from the left side to the left basic line marked with an axial line in front of the needle, and provided with a feed dog which is provided nearly to passage of the needle to move vertically and laterally. In such a sewing machine a cam portion is provided for supplying the lower thread to a lower thread contacting portion of the bobbin carrier or a lower thread contacting portion of a part connecting right and left teeth of the feed dog, whereby the amount of supplying the lower thread is adjusted properly with respect to the left basic line and the right basic line during zigzag stitching, and the slack amount of the lower thread is adjusted properly with respect to the left basic line and the right basic line during forming stitches.

Abstract: A thread feed device in a sewing machine is disclosed herein. The device comprises a thread paying-out member positioned in the thread path between the bobbin and needle, a pair of holding means positioned upstream and downstream of the paying-out member in the thread path and a control circuit for controlling of the operation of the holding means.

Abstract: A lockstitch sewing machine has a needle (22) and awl (24) mounted on a common pivot (52) and actuated each by a crank mechanism (40;72), the two mechanisms being mounted on a common crank shaft (38). Each mechanism is constituted by a bell crank lever (44;76); the two levers also being mounted on a common pivot (46). This latter pivot (46) is disposed intermediate the pivot (52) for the needle and awl and the crank shaft (38).

Abstract: A variable under thread pull off device in a sewing machine for providing the proper amount of slack in the bobbin thread to effect uniform stitch formation. The device will pull off a varying amount of bobbin thread to correspond to that which is required for each particular bight position of the stitch being set.

Abstract: A lockstitch sewing machine is provided with an elongate resilient member which is affixed at one end in the machine and extends under the feed dog of the machine for engagement thereby. The resilient member is flexed by the feed dog during downward movement thereof and then acts against bobbin thread pulling it from the bobbin spool. The elongate member relaxes and separates from the bobbin thread during upward movement of the feed dog.

Abstract: Three-dimensional thick fabrics are made from a laminate of fabric plies by first inserting pointed rods through the laminate to form rows of holes after which needles are reciprocated through the different holes to pull loops of various yarns through the holes. The loops of yarns in adjacent holes are interlocked to hold the plies together. A guide releasably clamped to each yarn controls tension in the yarn while a doffing point is employed to insure that the needle passes through a loop just formed when penetrating the next hole to insure interlock of the loops. Hollow circular objects are formed by winding a length of fabric a selected number of times around a form, following which the pointed rods are used to form holes in the resulting laminate with the needles and yarns being used to form the interlocking loops through the thickness of the laminate.

Abstract: The thread take-off device of the sewing machine is arranged between the needle thread reservoir and the thread tightener. This device is provided to prevent the direct take-off of the thread by the take-up lever from the storage spool by providing, in front of the tightener, an appropriate thread reserve without requiring any change in the path along which the thread is traveling. The take-off device comprises a lever oscillating synchronously with the take-up lever at right angles to the thread path. A lever portion, located in the rest position of the take-off lever, approximately at right angles to the thread and directly beside the latter, intersects with each downward movement of the take-up lever control arm, the travel path of the thread, whereby a thread reserve is pulled off from the spool. The return of the take-off lever is effected by a spring.

Abstract: An embroidering machine comprises a plurality of embroidering head each equipped with a plurality of needles formed into a group each with its thread. A needle bar is engageable with one needle at a time in the group to bring the needle from a rest position thereof into an operating position. A presser foot mechanism with a presser foot attached cyclically moves the presser foot upwardly and downwardly from an upper dead center position to a lower dead center position. The presser foot is provided with a hole for the passage of the one needle. Thread cutting and holding devices are provided for cutting the thread of the one needle to form a thread end portion and hold the thread end portion. Upon the termination of an embroidering operation with the one needle, the presser foot mechanism is operable to move the presser foot substantially transversely to a longitudinal axis of the needles and, after the thread is cut, to lift the presser foot upwardly beyond its upper dead center position.

Abstract: A thread handling system for a sewing machine is provided with a tensioning device without a check spring, a thread takeup member for pulling thread from the tensioning device and setting stitches, and a thread holder including a pair of elongated members which grasp and meter thread to a needle and looptaker. The tensioning device is disposed with respect to the operating limits of the takeup member to enable thread to be withdrawn from the tensioning device without being pulled from the thread source and with only slight thread tension.

Abstract: Circumferential stitching of a tubular workpiece is assisted by means of a moving support and feed system which includes a rotatable drum of smaller diameter than the workpiece having an upper end surface positioned adjacent to a stitching station with a conventional stitching mechanism. The workpiece is prepared for stitching by pulling it axially onto the drum like a sleeve. The portion of the workpiece to be stitched is then advanced transversely through the stitching station by a puller which engages the top of the workpiece while the drum is rotated synchronously to keep the workpiece from twisting. A portion of the drive system for the stitching mechanism runs through the interior of the rotating drum. A blind cutter next to the stitching station enables the operator to cut excess thread inside the workpiece after stitching simply by moving the workpiece in a certain manner.

Abstract: A lock stitch sewing machine is provided with mechanism controllable by a servo motor for pulling thread from a bobbin, and including a selectively positionable member operably connected with a feed dog and bobbin thread engageable means for causing thread to be pulled from the bobbin by the thread engageable means during downward motion of the feed dog in amounts determined by the position of the selectively positionable member.

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.

Abstract: A thread feeder for sewing machines is disclosed which feeds the thread from one of the bobbins to an automatic threading machine. It includes a movable table over the sewing machine, bobbins mounted thereon, thread tension regulators for adjusting tension to the thread from the bobbin, and feed rollers for feeding the thread from the thread tension regulator to the automatic threading device on a sewing machine. By such an arrangement, threads of different color or material can be fed conveniently one after another in a desired order.

Abstract: An automatic threading device for sewing machines is disclosed which can thread the needle thereon automatically. It carries with a stream of air the thread from a thread feeder through the thread take-up at standstill, guides it to the front of the needle hole, and passes it through the needle by means of a threading tool.