Abstract: Apparatuses, methods, and computer program products for quilting webs. A quilting machine includes a cutting edge, a looper from which thread is provided to form stitches, and an adjuster assembly that includes a plurality of selectable positions. The adjuster assembly extends an adjuster toward the thread between the looper and the retainer. When the adjuster is moved, a predetermined amount of thread is pulled away from the looper by the adjuster to provide a controlled length of thread between the looper and the cutting edge. The adjuster is configured to be moved to an intermediate selectable position prior to starting a quilting pattern, and from the intermediate position to another selectable position subsequent to starting the quilting pattern.

Abstract: A needle plate base in a multi-thread chain stitch sewing machine with a seam ravel preventing apparatus is divided into a left needle plate base for attaching a needle plate thereto and supporting a swinging support shaft of a thread hanging hook; and a right needle plate base for fixedly supporting a stopper member and a thread handling air cylinder and a stopper air cylinder. The right needle plate base is fastened to a sewing machine bed. The left needle plate base is fastenably and unfastenably fastened to an upper surface of the bed via screw members. Adjustment of stitch performation, and maintenance, e.g., replacement of various kinds of components stored inside the bed, can extremely easily and simply be carried out without having much trouble and requiring labor and time, and therefore, the stitch performation and predetermined ravel preventing function can be constantly surely reproduced.

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: 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: 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: The invention relates to a chain stitch sewing machine comprising stitch-forming sewing elements including at least one needle head (1) and needles (6) arranged on the needle head and at least one gripper shaft and gripper hooks arranged on the gripper shaft, wherein the needles (6) and the gripper hooks respectively form a sewing element pair and are driven in a manner such as to perform preferably chain stitches and especially double chain stitches in a sewing material arranged on a sewing material support, respectively using a needle thread and a gripper thread.

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: A double chain stitch sewing machine includes an upper section (10) and a lower section (12), which can be displaced synchronously parallel to a sewing product plane (14) The upper section includes a needle rod (18) holding a needle (20), and a drive (28) for displacing the needle rod perpendicularly to the sewing product plane. The lower section has a hook (40), which reciprocates in a plane parallel to the displacement direction of the needle rod and cooperates with the needle to form the stitch At least one needle stabilizer (42 or 44) in the lower section can be displaced synchronously with the needle rod and hook displacements between a first needle position close to the needle path, in which the needle stabilizer supports the needle against deflection transverse to the displacement path of the hook ,and a second position offset from the needle path.

Abstract: A mattress edge sewing machine including a frame having a material supporting surface, a sewing station defined by a needle bar mounted in the frame for generally vertical reciprocatory movements along a fixed centerline, and a feeding mechanism for pulling material through the sewing station of the machine. The feeding mechanism includes upper and lower positively driven feed rollers which are continually biased into operable engagement with each other. The feed rollers are arranged less than 0.8625 inches, measured in the direction of material advancement, separates the centerline of the feed rollers from the centerline of the needle bar. The needle bar is moved in timed relation relative to the movements of the looper, and with the needle bar traversing a distance in a single vertical direction at a ratio greater than 3:1 relative to the distance in a single lateral direction traversed by the looper.

Abstract: The invention relates to a chain stitch multi-needle guilting machine with stitch-forming quilting elements and a method for creating a pattern in a guilting material. The elements of the quilting machine are comprised of at least one needle bar with attached needles and at least one looper shaft with attached loopers. Each of the needles and the loopers have a corresponding needle thread and looper thread associated therewith, form quilting element pairs, and are driven to build chain stitches in a quilting material. At least one of the needles is adjustable between two positions and participates in the quilting procedure in a first position and does not prick into the quilting material in the second position during the quilting procedure. The quilting machine can be made to have a device to knot the needle thread with the looper thread, or a device to cut the looper thread, or both.

Abstract: Disclosed is a chainstitch sewing machine having a plurality of needles having needle threads which are moved up and down through needle holes of a throat plate, a looper having a looper thread, which is reciprocatively moved in a direction orthogonal to a cloth feeding direction under the throat plate, guide holes provided in the throat plate for guiding loops formed by the needle threads and a looper thread by the cooperation of the needles and the looper, to a rear part in a cloth feeding direction, and a main feed dog, disposed at a part closer to a rear than the guide hole, for feeding the loops in the cloth feeding direction.

Abstract: An improved chain stitch sewing machine that includes a stitch skip mechanism that is activated by the sewing machine operator such that the operator may cause the sewing machine to skip stitches as desired.

Abstract: A two-needle overlock sewing machine comprises a throat plate and a middle tongue. The throat plate has an opening needle hole and an outer tongue. The middle tongue is disposed parallel to the outer tongue, a thread chain is formed so as to envelop both tongues. The presser foot is disposed so as to press the cloth to the throat plate by a spring. A push-up lever lifts up the presser foot by handling. The push-up lever and the middle tongue are coupled together by a transmission mechanism. By raising the presser foot by manipulation of the push-up lever at the finish of sewing operation, the middle tongue draws back simultaneously and retreats from the needle hole. As a result, the manipulation for drawing back the middle tongue during the process of thread chain handling is not needed, and the operation is simplified.

Abstract: The over lock sewing machine for forming seams of an over-edge chain stitch and a double-thread chain stitch on a work cloth is provided with a needle bar holding a plurality of needles for forming a seam by a vertical reciprocating movement a plurality of loopers and a needle bar transmitting mechanism moving the needle bar in approximately orthogonal direction relative to a cloth feeding direction of the work cloth and the vertical reciprocating direction of the needle bar. Accordingly, the over lock sewing machine can make various decorative stitches with an over-edge chain stitch function and a zigzag stitch function. Moreover, the over lock sewing machine is capable with operation at a low cost.

Abstract: A thread taking-up tool is attached to a needle bar sticking out of a sewing machine head, and its leading end has a plurality of thread holes. The thread holes of the thread taking-up tool are arranged in the lateral direction. A thread handling body has a cam face in the vertical direction. Needle threads from a tension device to needles are controlled by the vertical motion of the thread taking-up tool and the action of the cam face of the thread handling body. When the needles ascend from the lowest position, an endless hook attached to the thread taking-up tool is engaged with the left needle thread between the cam face lower end and the thread hole of the thread taking-up tool. Each thread is handled in with the left needle thread staying at the cam face lower end, so that the needle thread loop at the remotest end is absorbed surely.

Abstract: An apparatus for preventing the raveling of a seam wherein a looper thread hanging hook for catching a looper thread which is allowed to pass through a loop of a needle thread immediately before the completion of a sewing operation and a driving mechanism of the hook together with a mechanism for cutting the looper thread and the needle thread are arranged on the right side of a needle drop point of a sewing machine.

Abstract: In a double chainstitch sewing machine, a movable thread guide 37 is fixed to the lower end of a needle bar 1. A fixed thread guide 41 and a thread take-up cam 39 are fixed to a jaw 43a of a sewing machine arm 43. The thread take-up cam 39 has a cam section to be engaged with needle threads 51a, 51b from the fixed thread guide 41 to the movable thread guide 37, and takes up the needle threads oscillating up and down by vertical motion of the movable thread guide 37. Thread take-up members such as movable thread guide 37, fixed thread guide 41, and thread take-up cam 39 are disposed centrally at the lower end of the needle bar near the needle and in the jaw 43a of the sewing machine arm 43. As a result, there is no member for thread take-up moving at the upper side and front side of the sewing machine arm, and dangerous positions for the operator can be decreased.

Abstract: In a double chainstitch sewing machine, a movable thread guide 37 is fixed to the lower end of a needle bar 1. A fixed thread guide 41 and a thread take-up cam 39 are fixed to a jaw 43a of a sewing machine arm 43. The thread take-up cam 39 has a cam section to be engaged with needle threads 51a, 51b from the fixed thread guide 41 to the movable thread guide 37, and takes up the needle threads oscillating up and down by vertical motion of the movable thread guide 37. Thread take-up members such as movable thread guide 37, fixed thread guide 41, and thread take-up cam 39 are disposed centrally at the lower end of the needle bar near the needle and in the jaw 43a of the sewing machine arm 43. As a result, there is no member for thread take-up moving at the upper side and front side of the sewing machine arm, and dangerous positions for the operator can be decreased.

Abstract: The invention relates to a method for producing sewn seams and a device for carrying out the method. The invention includes two sewing needles of which all moving parts are situated only on one side of the textile. Two or more sewing needles move obliquely and alternately penetrate the entire sewing material. The loop formed by a sewing thread is taken up by the next penetrating needle. The following penetrating needle then transfers the loops of the sewing thread. The sewing needles move three-dimensionally. The method and device are suitable for sewing large, curved material that should not be creased, for example, reinforcement fabric for fiber reinforced materials.

Abstract: A placket sewing machine attaches a placket patch to a fabric part of a garment in overlying relation to form a multiple layer placket assembly. The placket sewing machine includes a base defining a working surface of the sewing machine. A reciprocating needle chuck has first and second needle openings formed in a staggered forward and rearward arrangement. First and second sewing needles are positioned within respective needle openings of the chuck. The sewing needles are adapted for carrying respective ends of thread into and through the overlaid placket patch and fabric part to form first and second parallel lines of stitches in the placket assembly. The first line of stitches extends a greater distance along the length of the overlaid placket patch and fabric part than the second line of stitches. A sewing motor is operatively connected to the needle chuck for actuating the chuck during operation of the sewing machine.

Abstract: A needle plate for a two-needle interlock sewing machine for sewing a chain stitch seam of three threads, comprising two needle holes and one stitch tongue originating between the two needle holes and extending forward in a feed direction, thereby leaving open thread guiding slots along opposite sides thereof, characterized in that the thread guiding slots are covered in a needle stitching direction by marginal steps on the side of the needle plate except for thread outlet gaps open towards the bottom surface of the stitch tongue, where preferably the marginal steps form a support for the material to be sewn at their upper surface, each marginal step having a take-up ramp in the area of the thread guiding slots subsequent to the needle holes.

Abstract: A needle plate of a cover stitch sewing machine, adapted to introduce double chain stitch chain-off's, which are formed below a needle plate by the intertwining of threads on three needles and a thread on a looper in accordance with actions of the needles and looper occurring when fabrics to be sewn are not fed, onto the portion of an upper surface of the needle plate which is behind needle points, and feed out the chain-off's continuously with the chain-off's held between rear feed dogs on the rear side of the needle points and a chain-off thread gripper, is provided with a thread positioning spreader formed of retainers 10A, 10B having inclined portions indexed to the needle points and provided between recesses of the needle plate so that the chain-off stitches can be sewn continuously in a stable condition by a simple structure.

Abstract: A overedge sewing machine comprises: drive mechanisms for selectively carrying out a hemstitch sewing operation and flat stitch and double-chain stitch sewing operations; a needle plate having a stitch finger, a guide needle piece and a stitch tongue reciprocatable between an operation position and a non-operation position outside the needle plate claw and guide needle; and three needles mounted removably thereon in such a manner that the three needles are arranged in parallel to each other substantially on a straight line, wherein a needle point which is used in common with the overedge sewing operation and the flat stitch and double-chain stitch sewing operations is positioned between the stitch tongue and the guide needle piece respectively provided in the needle plate.

Abstract: An upper decorative stitching spreader 11 is switched active or inactive by an upper decoration switching mechanism 25. By placing the spreader 11 in active state, upper decorative stitches which are formed from above the fabric are added to the conventional over-edge chain stitches and lower decorative stitches which are formed from below the fabric. On the other hand, by placing the spreader 11 in an inactive state; that is, by stopping the spreader 11, over-edge chain stitching without upper decorative stitching, and lower decorative stitching which is performed from below the fabric are performed without interference with the spreader 11.

Abstract: A thread control apparatus for a double chain stitch sewing machine of the present invention is applied to the case of sewing a cloth with a double chain stitch sewing machine having multiple needles, and forming a thread chain consecutively to the sewing end of the cloth. Two thread tensioning devices change over and apply mutually different thread tensions to needle threads and to a looper thread passed through a plurality of needles and a looper, respectively, when sewing the cloth and when forming a thread chain. An other looper thread tensioning device disposed in a thread route between a looper thread take-up device and the looper. The other looper thread tensioning device limits the draw-out amount of thread by pinching the looper thread from the looper thread take-up device to the looper side only when forming a thread chain, and therefore a tight thread chain may be securely formed when forming a thread chain.

Abstract: The method and apparatus for preventing seam from raveling in a double chain stitch sewing machine of the invention are applied mainly in sewing of cloth by a double chain stitch sewing machine with multiple needles, and when nearing the end of sewing for forming a double chain stitch S by collaboration of a plurality of needles 5, 6 and a looper 3, a looper thread 10 consecutive from the cloth W to the looper 3 is engaged with a hook 15, and in this state, consequently, needle threads 8, 9 consecutive to the needles 5, 6 from the cloth W through the looper 3, and the looper thread 10 consecutive to the looper 3 from the cloth W are cut off, and the looper thread 10 engaged with the hook 15 is also cut off simultaneously or before or after this cutting, and therefore the looper thread 10 consecutive to the sewing end of the cloth W is set in discontinuous state, and raveling of sewing thread is securely prevented, while the length of the thread end consecutive to the sewing end is shortened, so that a sewn pr

Abstract: In a multi-needle double chain stitch sewing machine, when forming a thread chain after forming a seam without using upper cover thread, formation of loop or excess looseness of the right needle thread is prevented. A U-shaped guide having a pair of thread eyes at both opposing ends is fixed at the lower end of a needle bar, and a thread take-up cam extending in the vertical direction is fixed on the sewing machine frame between said thread eyes. The upper half of the cam working surface has a linear shape and the lower half has a sloping curve. The right needle thread passed between the thread eyes is brought into contact with the cam, and when the U-shaped guide descends together with the needle bar, the right needle thread is gradually bended.

Abstract: A needle plate for a sewing machine includes an opening formed in one side portion. On or more tongues may be secured to the needle plate and extended inward of the opening so as to conduct various kinds of sewing operations. A bracket is secured to the needle plate and includes a channel. A lever is slidably engaged in the channel and includes another tongue movable away from the previous tongue and movable toward the position located beside the previous tongue so as to form another tongue.

Abstract: In a two-needle sewing machine for making an ornamental stitch without a cover stitch, at least one intermediate lug (17) is provided which is disposed in side by side relation with respect to an upper thread take-up (13) engaged to the needle bar (7), said intermediate lug, in the absence of a workpiece (4) on the needle plate (8), is brought to a work position in which it interferes with one of the needle threads (4a, 4b) coming from an auxiliary thread take-up (12) being part of a feed unit for the needle threads. In the presence of the intermediate lug (17) in the work position, the orientation of the needle thread (4a) intercepted by said intermediate lug is suitably deviated with respect to the upper thread take-up (13), so as to cause a tension release on the needle thread itself during the raising steps of the needles (3a, 3) towards the upper dead center of their reciprocating motion.

Abstract: A sewing machine possessing multiple needles and a single looper for forming a double chain stitch without an upper covering thread capable of drawing out a thread chain reliably and smoothly. By using an auxiliary blade disposed parallel to a looper, the thread chain consecutive to the looper is supported, thereby preventing the thread chain from being pushed down beneath a throat plate by descending needles. On the throat plate, a stitch formation tongue composed of a movable slender plate is provided, and this tongue is withdrawn when making the thread chain. The sewing machine is provided with tension regulators for sewing and for forming a thread chain respectively. In the tension regulators for forming the thread chain, the tension of the right needle thread is set lower than the tension of the looper thread. By use of a rear feed dog, the thread chain is drawn out through a guide groove at the left rear end of a needle hole toward the middle of the rear feed dog.

Abstract: An apparatus and a method for supplying thread in a chain stitch sewing machine are disclosed, the apparatus comprising a needle vertically reciprocating between a top end point and a bottom end point in one sewing cycle; a looper horizontally reciprocating in one sewing cycle; a thread supply device for forcibly supplying a needle thread to the needle; and a thread supply control device for controlling the thread supply device so that the needle thread is supplied in at least two periods in each sewing cycle, the periods being discontinuous.

Abstract: Apparatus and method for severing the needle and looper threads of a chain stitch formed by a cylinder bed sewing machine having an in-line looper system is disclosed. The cylinder bed sewing machine has a needle plate and a needle carrying the needle thread through the material and the needle plate to form a needle loop of needle thread therebelow that has a needle side running to the needle. The apparatus comprises a device operating as a dual needle plate holder and knife slide base, a stationary knife positioned below the needle plate, a spring positioned below said stationary knife, a movable knife positioned on the knife slide base and slidably mounted between the stationary knife and the spring for yieldingly urging the movable knife thereagainst. The movable knife has one penetrating end with a pair of axially offset barbs, a lagging barb and a leading barb closer to the penetrating end of the movable knife than the lagging barb.

Abstract: A taped chaining thread sewing device is designed to sew by operation of an overedge sewing machine a tape into the upper surface of the fabric sent into the needle location of the sewing machine, and also sew the chaining thread cut off from the preceding fabric into the lower surface of the fabric. The tape is cut off together with the unnecessary edge portion of the fabric by a cutter at the start of sewing of the leading end from the sewing part on the fabric. Before the final end of the fabric passes the cutter, a tape guide of the taped chaining thread sewing device moves, and therefore the unsewn portion of the tape is cut off together with the unnecessary edge portion of the fabric from the sewn part by the cutter. By the chaining thread sewn into the beginning part of sewing of the fabric, it is not necessary to perform any particular bar tacking job at the beginning of sewing in a separate process.

Abstract: A needle thread feed regulating device utilized in high speed overedge sewing machines which form safety stitches composed of overedge stitches and double chain stiches. The needle thread feed regulating device comprises a thread guide mounted on the sewing machine frame and an oscillating thread guide which moves in cooperation with the sewing machine main shaft. The oscillating thread guide has a cam plate which regulates the feed of both the thread for overedge stitches and the thread for double chain stitches.

Abstract: A device for forming a thread chain on a multiple-needle chainstitch sewing machine having at least two sewing needles, a looper, a needle plate having at least two needle hole slots and a stitch formation tongue disposed between the needle hole slots, and a feed device comprising a feed dog and a presser foot, and a sewing thread brake device disposed beneath the stitch formation tongue beyond the sewing needles in the direction of sewing. The device brakes the sewing threads, and deflects them in such a way that a thread chain is formed.

Abstract: A sewing machine has a needle bar, which is mounted in a frame, a continuously operating feed device for the workpiece, a looper which reciprocates transversely to the workpiece feed direction, a spindle which is mounted in the sewing machine arm, and a cam, which is disposed on the arm spindle in order to swing the frame in the workpiece feed direction. The frame is driven in dependence upon the movement of the arm spindle by way of a positively connected transmission. Two cams permit optimum adaptation of the swinging movement of the frame to the continuously moving workpiece.

Abstract: This invention provides an overlock sewing machine with a threading mechanism that is both easier and more efficient to use. As shown in FIGS. 1 and 7, the overlock sewing machine has a vertically movable needle (6, 106), a looper carriage (18, 118) connected to a rotating shaft, and a looper (11, 111) on the end of the looper carriage. The looper extends laterally over the looper carriage and has a thread-receiving eye (11a, 111a). The looper and the needle cooperate to form a chain stitch. As shown in FIGS. 3 and 9, a thread-guiding member (25, 125) next to the looper pivots with the looper to guide a thread LT through the thread-receiving eye. A movable lever (30, 130) pivots with or relative to the looper. A thread-delivering member (39, 139) mounted on the movable lever that can be set in two positions: a first position corresponding to a first position of the thread-receiving eye, and a second position corresponding to the thread-guiding member.

Abstract: A method and an apparatus for changing the sewing direction of a multiple needle flat sewing machine for sewing elbow pads of sports wear, jumpers, etc. and patchworks of various shapes. Needles are stopped at the needle upper dead center position; a throat plate is moved in a direction contrary to the sewing direction; a needle thread or looper thread caught on tongues of the throat plate is released from the tongues; and the sewing direction can be changed at any desired angle in relation to the sewing direction at the start, such as a right angle, an acute angle or an obtuse angle. The present invention also makes it possible to carry out fancy stitching with thick thread by a multiple needle flat sewing machine.

Abstract: A sewing machine comprises a bed 3 on which a work-supporting table 3a is defined and from which a post 4 carrying a cantilevered support arm 5 provided with a needle-holding head 6 at its free end, rises up. An upper shaft 9 performing a rotating motion is housed within the arm 5 and it imparts a reciprocating movement, through a connecting rod-crank linkage 10, to a needle bar 11 vertically slidable in the head 6. Along the upper shaft 9 a plurality of eccentrics 19, 20, 21 are distributed to which auxiliary sewing operation devices 22, 32, 39 detachably associated with the sewing machine 1 are operativley engageable through respective connecting rods 23, 33, 50 and transferring motion mechanisms. A preformed opening 5 is formed in the support arm 5, through which connecting rod 50 is mounted to eccentric 21. An opening 36 is formed in support arm 5 through which stem 37 passes.

Abstract: A device for operating and orientating a pair of automatic sewing machine needles have two needles which are locked to the lower ends of two equal rods, located beside one another in the vertical plane. These needles change over position during stitching without requiring reorientation of the needles themselves. The device has a cylindrical element movable in the vertical plane, which has the needles and rods therein. The device also includes a sleeve and guides for guiding the vertical movement of the cylinder, with driving means for driving the sleeve and cylinder such that the orientation of the rods is unaltered when they change over position. This enables the needles to operate in conjunction with the looper of an automatic sewing machine to which the device is fitted.

Abstract: A thread cutter for an interlock sewing machine wherein the sewing machine has a small diameter cylindrical arm and the cloth being sewn is fed along the axis of the arm. A plurality of needles are disposed along a line orthogonal to the axis of the arm and an arcuated, movable member having a hook at its tip is pivotably supported ahead of feed dogs on the sewing machine relative to the line of feed. The arcuated, movable member is turned by means of an operative plate disposed along the axis of the arm and, in cooperation with a fixed blade, cuts threads after the cloth has been sewn.

Abstract: A device for a two-needle overedge sewing machines for sewing in a thread chain. The device has a pair of needles, and a pair of slots in a needle plate for the needles. The device further has a pair of stitch formation tongues, and a directing mechanism in order to guide the thread chain into a needle hole slot between one of the stitch formation tongues.

Abstract: A thread chain is prevented from hanging at an inner chain-off finger when it is turned back or rotated to the operator's side for holding and cutting. A needle thread, positioned at the front side of a lower looper, is guided by a needle thread restricting device, and a needle thread positioned on the back side of a lower looper is prevented from being hung on an inner chain-off finger by a thread chain guiding device provided at a throat plate so that enfolding back and tacking of the thread chain into the fabric material is performed well.

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 reciprocally driven needle guide movable in timed relation with sewing machine needles above the work support of a sewing machine along a substantially horizontal path. The needle guide is provided with an extended guiding surface which is positioned adjacent the vertical path of the sewing machine needles to steady the needles while they are above the work supporting surface of the machine.

Abstract: A sewing machine wherein the various stitch performing instrumentalities are driven by Cardan gear means. Particular sewing part mechanisms are associated with each of said Cardan gear means to produce the desired stitch. Both said sewing part mechanisms and said Cardan gear means being removable, and interchangeable within the frame of the sewing machine.

Abstract: A mechanism for seizing and holding a thread, particularly the looper thread, of a chainstitch sewing machine to insure needle penetration of the thread triangle thereby assuring enchaining of the needle thread with the looper thread. Such mechanism includes an oscillatable thread spreader which transversely moves across the looper's endwise path of travel. The spreader motion being in timed relation with the stitch forming instrumentalities such that its effectively travel extends between the looper eye and the reciprocal path of the needle arranged closest to the looper eye when the looper is at its extreme loop seizing position.

Abstract: A needle protector for sewing machines operatively connected to the machine's horizontal shaft for driving its looper in an orbital pathway about the machine's needles. The horizontal shaft is simultaneously driven through oscillating and reciprocating movements. The needle protector is carried on a pivotable support and the reciprocating movement of the horizontal shaft is effective in moving the needle protector toward and away from the needles in timed sequence with the stitch forming cycle.

Abstract: A mechanism for driving needles of a sewing machine to produce for example a two thread interlocked chain stitch. To a frame is mounted a pair of eccentric cams for rotation generally about 180.degree. out of phase with each other about an axis, the cams having peripheral bearing surfaces of predetermined contour. The shape of the peripheral bearing surfaces of the eccentric cams and of inner and exterior bearing surfaces on circumscribing cam cage followers, and the position of edge guides positioned about the outer surface of the cam cage followers so as to bear against parts of the cam cage followers, are such as to provide relative movement and orientation of each cam cage follower in a complete cycle to permit sewing machine needles associated with the cam cage followers to stitch a chain stitch.