Abstract: A restoring device of a tension adjusting device in a transverse arm for a sewing machine includes a main part which has an active member and a passive member on two sides thereof so as to drive two sides of a pressing board of the control set. When the user adjusts the adjusting knob, the control set of the tension adjusting mechanism can be adjusted by the movement of the pressing board so as to prolong the life of use of the control set.

Abstract: A thread tension adjustment device of multi-needle sewing machine including: a fixing rack fixed on a housing of the sewing machine; multiple frame bodies side by side fixed on the fixing rack; multiple thread tension adjustment units mounted on the frame bodies, each thread tension adjustment unit serving to resiliently clamp a thread, multiple thread-loosening slide boards being respectively slidably disposed on the frame bodies, each thread-loosening slide board having multiple wedge sections; and a link pivotally connected with the thread-loosening slide boards for driving the thread-loosening slide boards to move the wedge sections thereof toward the corresponding thread tension adjustment units to release the threads clamped by the thread tension adjustment buttons of the thread tension adjustment units.

Abstract: A bobbin case assembly having a wall structure mountable upon a support, a bobbin for a supply of thread, and a tensioning element for engaging thread projecting from a supply of thread on the bobbin. The tensioning element has a length and a circumferential surface against which thread can be wrapped so that a frictional resistance force can be generated between the thread and circumferential surface that resists drawing of thread off of the supply. The tensioning element has a configuration that limits lengthwise shifting of a spirally wrapped portion of thread wrapped against the circumferential surface.

Abstract: A sewing apparatus such as a sewing machine includes a cassette mount to which a thread cassette having a thread accommodating section for accommodating a thread supply is detachably attached, at least one detector detecting an operating state of at least one mechanism related with the thread cassette, a determining unit determining whether the thread cassette can be attached to the cassette mount, based on a result of detection by the detector, and an informing unit informing a result of determination by the determining unit.

Abstract: A sewing machine includes a thread tension adjusting device, and a thread tension releasing device. The thread tension adjusting device includes a thread press member formed with a release extension portion. The thread tension releasing device presses the release extension portion of the thread press member to pivot the thread press member so as to move the thread clamping portion of the thread press member. Thus, the thread tension releasing device directly presses the release extension portion of the thread press member, so as to release the tension of the sewing thread, so that the tension of the sewing thread can be released easily and rapidly.

Abstract: A sewing machine includes a thread tension adjusting device, and a thread tension releasing device. The thread tension adjusting device includes a thread press member formed with a release extension portion. The thread tension releasing device presses the release extension portion of the thread press member to pivot the thread press member so as to move the thread clamping portion of the thread press member. Thus, the thread tension releasing device directly presses the release extension portion of the thread press member, so as to release the tension of the sewing thread, so that the tension of the sewing thread can be released easily and rapidly.

Abstract: A sewing machine includes a thread cassette having a thread accommodating cavity in which a supply of thread is accommodated, a cassette mount to which the thread cassette is detachably attached, a thread tensioner adjusting a tension of the thread drawn from the thread cassette, a detachment operating member operated so that the thread cassette is detached from the cassette mount, and a thread tension control controlling the thread tensioner so that the thread is set at a predetermined tension when the detachment operating member has been operated.

Abstract: A thread tensioning device or apparatus for a sewing machine enables accurate, repeatable measurement and monitoring of the compression forces applied to the thread tensioning discs thereof. The apparatus further includes a visual display or output corresponding to the actual amount of compressive force being applied. The device further includes a comparator, which compares the electrical signal to a predetermined reference value to control or regulate the normal operation of the sewing machine.

Abstract: A sewing machine includes a thread cassette having a thread accommodating cavity in which a supply of thread is accommodated, a cassette mount to which the thread cassette is detachably attached, a thread tensioner adjusting a tension of the thread drawn from the thread cassette, a detachment operating member operated so that the thread cassette is detached from the cassette mount, and a thread tension control controlling the thread tensioner so that the thread is set at a predetermined tension when the detachment operating member has been operated.

Abstract: A sewing machine for forming running-stitch seams, comprises a needle provided, proximate to its tip, with an open eye and orientated so that its axis is substantially perpendicular to a surface for supporting the item being sewn. The needle is actuated with a reciprocating motion along its own axis passing cyclically through the supporting surface. A thread take-up wheel is provided below the supporting surface and is composed of a fixed part, with a magazine for the taken-up thread, and a rotatable part, rotationally actuated about its own axis. The rotatable wheel part supports a lower looper engaging the thread loop below the supporting surface to load the thread in the magazine formed in the wheel fixed part. Pneumatic tensioning means for the thread portion lying below the supporting surface are further provided.

Abstract: A pair of tension discs is disposed on a tension stud fixed in part of a sewing machine main body. A pneumatic cylinder has a drive rod. The drive rod moves at least one of the tension discs to other tension disc so that one tension disc is pressed to other tension disc. An air regulator is interposed between the pneumatic cylinder and an air supply source, being composed in an electropneumatic system for converting between voltage and air pressure. By controlling the applied voltage to the electropneumatic air regulator on the basis of an instruction from a microcomputer, the set pressure of the air supplied to the pneumatic cylinder is adjusted. Thereby the pressure to the thread held between the pair of tension discs, that is, the thread tension is controlled. As a result, without having to stop the operation of the sewing machine, the thread tension can be adjusted promptly and appropriately.

Abstract: A pair of tension discs is disposed on a tension stud fixed in part of a sewing machine main body. A pneumatic cylinder has a drive rod. The drive rod moves at least one of the tension discs to other tension disc so that one tension disc is pressed to other tension disc. An air regulator is interposed between the pneumatic cylinder and an air supply source, being composed in an electropneumatic system for converting between voltage and air pressure. By controlling the applied voltage to the electropneumatic air regulator on the basis of an instruction from a microcomputer, the set pressure of the air supplied to the pneumatic cylinder is adjusted. Thereby the pressure to the thread held between the pair of tension discs, that is, the thread tension is controlled. As a result, without having to stop the operation of the sewing machine, the thread tension can be adjusted promptly and appropriately.

Abstract: A sewing machine for forming running-stitch seams, comprises a needle provided, proximate to its tip, with an open eye and orientated so that its axis is substantially perpendicular to a surface for supporting the item being sewn. The needle is actuated with a reciprocating motion along its own axis passing cyclically through the supporting surface. A thread take-up wheel is provided below the supporting surface and is composed of a fixed part, with a magazine for the taken-up thread, and a rotatable part, rotationally actuated about its own axis. The rotatable wheel part supports a lower looper engaging the thread loop below the supporting surface to load the thread in the magazine formed in the wheel fixed part. Pneumatic tensioning means for the thread portion lying below the supporting surface are further provided.

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: A buttonhole sewing machine for the production of buttonholes on a work-piece comprises a thread feeding mechanism on the path of a needle thread which is fed in a direction of delivery. The thread feeding mechanism comprises a pivotal thread lever which has an opening for the needle thread to be led through. Further, the thread level is drivable by a triggerable positioning motor to pivot between a zero position and several positions of thread extraction.

Abstract: Native code for a CNC stitching machine is generated by generating a geometry model of a preform; generating tool paths from the geometry model, the tool paths including stitching instructions for making stitches; and generating additional instructions indicating thickness values. The thickness values are obtained from a lookup table. When the stitching machine runs the native code, it accesses a lookup table to determine a thread tension value corresponding to the thickness value. The stitching machine accesses another lookup table to determine a thread path geometry value corresponding to the thickness value.

Abstract: The combination of a bobbin case assembly and a supply of thread. The bobbin case assembly has a wall structure defining a receptacle for the supply of thread and a thread tensioning assembly on the wall structure including a thread tensioning element. The supply of thread projects from the receptacle and is wrapped at least partially around the thread tensioning element so as to produce resistance to the removal of the thread from the receptacle.

Abstract: A double thread chain-stitch sewing machine with a platform containing a needle, a needle plate with a slot, a pressing leg, a looper and a toothed rack for transporting a material, characterized in that it additionally has autonomous disk-shaped cam thread tensioners for a top and a bottom thread and a pusher for the bottom thread installed with the possibility of executing an oscillating movement around its axis, and the looper is installed with the possibility of executing a rotary movement in a vertical plane, parallel to the stitch line and with the possibility of performing two revolutions per one cycle of movement of the needle and the pusher.

Abstract: A lock stitch sewing machine with an automatic thread tension adjusting device is disclosed, wherein the sewing machine has a plurality of thread tension adjusting mechanisms 7, each of which including a pair of thread tension disks 12, 13, one of which is normally pressed by a spring toward the other. A sensor 4 is responsive to the operation of a thread tension releasing lever 20 made by a user with a slight touch applied thereto to give a signal. A CPU1 is responsive to the signal to compare the value of the existing thread tension of the thread tension adjusting mechanisms 7 with a predetermined one. If the value of the existing thread tension is higher than the predetermined one, the CPU1 is operated reduce the value of the existing thread tension to a predetermined one. Thus the tension releasing operation ability is increased.

Abstract: A sewing machine includes a needle bar rocking mechanism for rocking a needle bar in a direction crossing a direction in which a workpiece cloth to be sewn is fed, a thread tension applying mechanism for applying tension to a needle thread supplied from a needle thread supply to a sewing needle mounted on the needle bar, a thread tension releasing mechanism operating the thread tension applying mechanism so that the needle thread is released from the tension applied to it by the thread tension applying mechanism, and a single rotary actuator for driving both of the needle bar rocking mechanism and the thread tension releasing mechanism.

Abstract: A thread tensioning and drawing-back device for pile warp threads of a weaving machine, which device comprises provisions (2) for braking, by spring elements, pile warp threads (4) taken up by a weaving machine, and provisions (5) for drawing back the pile warp threads (4) in case of variations of warp length resulting from changing the shed position of the weaving machine, in which the provisions (2) for braking the pile warp threads (4) consist of disk springs (2) placed next to each other in a row on a horizontal spindle (3), each provided for braking one pile warp thread (4). The device can furthermore comprise preferably detachable tension spindles (11), (12) at the entrance to the disk yarn brakes (2) and at the exit from the disk yarn brakes (2).

Abstract: A sewing machine includes a thread tension applying mechanism for applying tension to a needle thread supplied from a needle thread supply source to a sewing needle, a thread tension releasing mechanism for releasing the thread tension applying mechanism from a tension applying state, a spring for driving the thread tension releasing mechanism, a switching mechanism for switching the spring between an operative state and a non-operative state, and a drive source for driving the switching mechanism.

Abstract: A computerized stitching apparatus that automatically controls thread tension is disclosed. In one embodiment, at least two factors are used to determine the desired thread consumption for the next stitch. A thread length encoder is used to determine the amount of thread actually consumed for a particular stitch. The operator must enter a desired thread length ratio or an equivalent factor related to desired thread length used for a particular stitch into the operator input device. Another factor such as speed, stitch length, fabric thickness, or stitch angle change is used with at least the operator's input to determine the desired thread consumption. The tension of the thread is adjusted by the stitch control system which will affect the actual thread consumed for the particular stitch.

Abstract: This invention relates to an improved automatic sewing machine apparatus for sewing large articles, in lock-stitch or chain-stitch, employing two completely different upper and lower sewing mechanisms which are separately powered, wherein there is no continuous mechanical, electrical, hydraulic or other fixed connection between the upper and lower sewing mechanisms required. An open notched needle has a notch opening disposed near the needle end, the notch opening engages the needle thread, and carries the needle thread through the sewing material, and then leaves a loop extending through the sewing material as the notched needle raises above the sewing material. The notch opening in the needle is rethreaded during each cyclic, reciprocating actuation of the notched needle. A looper having two forked arms passes the thread loop around the bobbin case. The position of the open notched needle determines the timing of the looper actuation. The open notched needle position is sensed through the sewing material.

Abstract: A stitching head for a computer numerically controlled stitching machine includes a thread tensioning mechanism for automatically adjusting thread tension according to the thickness of the material being stitched. The stitching head also includes a mechanism for automatically adjusting thread path geometry according to the thickness of the material being stitched.

Abstract: A needle thread restraining device in a thread cutting sewing machine comprising a needle thread restraining device 18 which is disposed on a needle thread path between a needle take-up mechanism (5) and a needle thread supplying source (6) for setting the tension of the needle thread 4 to substantially zero when the thread cutting mechanism (9) does not operate and to a given value when the thread cutting mechanism (9) operates, and a tension nullification means 31 for setting the tension applied by a tension regulator (10) to a given value when the thread cutting mechanism (9) does not operate and for nullifying the tension applied by the tension regulator when the thread cutting mechanism operates. The amount of the needle thread to be drawn under the work can be set properly and independently, nullifying of the tension set by the tension discs when the sewing thread is cut by the thread cutting mechanism.

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: An overlock sewing machine which can readily form a rolled seam with no requirement for a complicated tension adjusting operation is disclosed. In this overlock sewing machine, an auxiliary thread tensioner (15) is provided independently of a main thread tensioner (4), providing a lower looper thread (9) with thread tension which is necessary for forming an over-edge chain stitch, in the vicinity thereof. An end cam (25) is provided on a shaft (13) of a dial (12) for feed adjustment, so that an upper pawl (23) rams one portion of the peripheral edge of a tension disc (20) and expands a side which is opposed thereto for canceling tension provision to the lower looper thread (9) passed through tension discs and provides the tension only by the main thread tensioner (4) to carry out an ordinary over-edge chain stitch when a lower pawl (24) is engaged with a high lift part of the end cam (25).

Abstract: A sewing machine is provided for splicing together two different threads. The machine includes a thread tree with a number of thread spools with each thread thereof being inserted through flexible plastic tubing. A movable carriage assembly locates the new thread to be spliced relative to a splicing device passageway that receives the new thread to be spliced along with the old thread. The splicing device includes a front air inlet for drawing the new thread into the passageway of the splicing device and a rear air inlet for creating air turbulence during the splicing operation. Also used in moving the new thread through the passageway is an insertion drive roller connected to a pivotal rocker. A thread clamp cover connected to the rocker cooperates with the trimmer blades to trim the old thread. A thread clamp and a thread clamp magnet cooperate to hold the old thread in a desired position during the insertion of the new thread into the splicing device.

Abstract: A thread tensioning device for a sewing machine includes two plates engaged on a shaft and a spring for biasing the plates toward each other in order to clamp a thread. The plates each includes a thread receiving portion and each includes another portion opposite to the thread receiving portion. A projection is engaged between the opposite portions so as to separate the opposite portions away from each other and so as to form a closely contacted outer peripheral portion in the thread receiving portions, and in order to force the thread toward the shaft.

Abstract: A thread tension device includes a pair of discs engaged on a shaft and a spring for biasing the discs to clamp a thread. A follower is threadedly engaged on the shaft for adjusting the spring. A barrel is engaged with the follower so as to rotate the follower. A cap is rotatably engaged on the barrel. A latch is slidably engaged in the barrel for engaging the barrel with the cap so as to allow the barrel and the cap to rotate in concert when the latch is engaged with the cap. The barrel is allowed to rotate freely relative to the cap when the latch is disengaged from the cap.

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: 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: 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: A thread control apparatus having first and second thread retainer or holder mechanisms on a thread path, a feed passage control mechanism adapted to obtain the thread in a zig zag form between the first and second thread holder mechanisms, and a controller actuated to allow these holder mechanisms to be in a thread hold condition and a thread release condition, respectively, just before starting thread cutting or trimming operation. Slack is provided in the thread by deactuating the feed passage control mechanism after the thread has been delivered from the thread supply source by operation of the feed passage control mechanism. The thread is released by the first thread retainer mechanism and held by the second thread retainer mechanism until the next sewing operation is started upon trimming or cutting the thread to render the thread path longer by means of the feed passage control mechanism, thereby drawing back the residual thread.

Abstract: A stitch balancing thread tension device for a sewing machine, the body of which is inserted into the opening portion of the sewing machine body, wherein the thread tension device body for supporting a stem on which a pair of tension discs are fit, comprises a projecting portion which contacts the outer side surface of the sewing machine body and pawls which are retained at the circumferential edge of the opening portion by the inner side surface of the sewing machine body for clamping the sewing machine body therebetween. The pawls are elastically invaginable into the thread tension device body to release the sewing machine body from clamping. Since the thread tension device can be attached to or detached from the sewing machine body in one-shot operation, the operability is remarkably improved in efficiency.

Abstract: A thread tension device for overlock sewing machines, which provides a thread tensioner and a regulator. The thread tensioner includes a pair of thread tensioning discs supported on a rotatable shaft and slidably movable axially on said shaft and a spring having one end supported on a spring holder threadably movable on a sleeve and the other end abutted against one of the thread tensioning plates. The regulator includes a rotary member fixed to the shaft and rotatably driven with the shaft; and a follower having one side held against the rotary member and the other side abutted against the other one of the thread tensioning plates over the spring.

Abstract: A thread tension adjusting apparatus, used in a sewing machine, adjusts tension of a supplied thread by adjusting a thread holding force. The apparatus is provided on a thread supply path running from a thread source to a thread processing section such as a needle and a looper. The thread tension adjusting apparatus comprises a pair of members respectively having portions opposed to each other. At least one of the members is a piezoelectric actuator for changing a distance between the portions when being driven, whereby to adjust a thread holding force.

Abstract: The thread tension regulating apparatus comprises; thread tension setting means for selecting and setting thread clamping pressure to the right pressure coping with plural kinds of the stitches; thread tension fine-adjusting means for allowing fine-adjustment of thread clamping pressure in the thread tension regulating apparatus by moving clamping pressure of the thread tension regulating apparatus from the original position to a higher position; said clamping pressure having been adjusted by said thread tension setting means; and home-position resuming means for returning the thread tension fine-adjusting means to the home position from another position when selecting and setting another thread tension by using the thread tension setting means.

Abstract: A stitching mode changer for an overlock machine which enables stitching modes, i.e., ordinary overlock stitching, standard roll hemming, and special roll hemming, to be changed by a one-touch control operation and which is free from danger of an accident, e.g., breakage of a looper, due to erroneous operation. When a fabric feed dial is set to a feed rate for the ordinary overlock stitching, an adjusting member is flush with a needle plate, but, when the fabric feed dial is adjusted to a feed rate for the standard roll hemming, a cam that is secured to the dial rotates, so that a lever that abuts on the cam surface of the cam pivots, causing the adjusting member engaged with the lever to withdraw below the needle plate. The advance and withdrawal of the adjusting member are reliably effected by a combination of a spring and a retainer for guide, which are provided on a lower knife mount that supports the adjusting member.

Abstract: A thread tension device including a plate fixed on a sewing machine, a bolt rotatably engaged in the plate, a pin engaged on the plate, a dial rotatably engaged on the bolt and having a number of holes for engagement with the pin, a pair of levers extended from the plate, a pair of discs engaged between the plate and the dial for clamping a thread, a follower threadedly engaged on the bolt and having two notches engaged with the levers, a spring biasing the discs together, whereby, the follower is rotatable by the dial when the dial is pushed inwards of the knob.

Abstract: A tension regulating device can set an indicating value of a thread tension. The tension regulating device comprises a regulating nut which is screwed into the male portion of a tension regulating shaft for compressing the tension regulating spring and a regulating dial having scales. The regulating dial is rotatable to turn the regulating nut to set the tension of a thread, which is held by the tension discs in response to the turning position of the regulating nut. The tension regulating device further comprises a regulating dial stop retained by a step portion of the tension regulating shaft and a short cylindrical member fixedly engaged in the cylindrical portion of the tension regulating shaft for clamping the regulating dial stop. The short cylindrical member has spline grooves defined at the outer periphery thereof.

Abstract: A thread tension adjusting apparatus, used in a sewing machine, adjusts tension of a supplied thread by adjusting a thread holding force. The apparatus is provided on a thread supply path running from a thread source to a thread processing section such as a needle and a looper. The thread tension adjusting apparatus comprises a pair of members respectively having portions opposed to each other. At least one of the members is a piezoelectric actuator for changing a distance between the portions when being driven, whereby to adjust a thread holding force.

Abstract: A device including an axle rotatably supported in a sewing machine, a shaft fixed in parallel to the axle, one or more cams fixed on the axle, a lever having one end pivotally fixed and having the other end slidably engaged with the cam, and a gripping device including a pair of members disposed on the shaft and a spring disposed between the lever and the members so that a thread can be gripped between the members, and the lever can be caused to move toward or to move away from the members so that a tension force applied to the thread can be adjusted.

Abstract: A thread cutting arrangement for sewing machines including an arrangement in which the tension of the thread is released in both directions of movement of an axially moveable drive mechanism such that the thread tensioning mechanism is opened when the needle thread is caught. The movement of the drive mechanism is transmitted via a one-way coupling so that the opening of the thread tensioning mechanism is limited to the duration of the after pawal of the needle thread.

Abstract: A device is provided for controlling the tension of a longitudinally moving thread. The device includes at least two adjacent plates which are applied one against the other and between which the thread passes. The plates, and thus the thread, can be tightened so that the desired tension can be creatred. Opposed surfaces of the plate each incorporate at least one gripping surface for the thread which cooperates with at least one corresponding gripping surface of the other plate. The periphery essentially about the surfaces is formed with at least two indentations arranged in such a way that each indentation of the gripping surface of a plate coincides with at least a portion of a corresponding indentation on the gripping surface of the other plate.

Abstract: A sewing machine provided with a thread cutting mechanism and a needle thread tension release mechanism. Normally, the needle thread is subjected to a proper tension by a thread tension regulating mechanism. However, at an initial start-up period of the sewing operation, the needle thread tension is released by the tension release mechanism for a first predetermined period during which a needle thread loop is trapped by a loop taker. Further, the sewing machine is provided with a thread holding member for holding a leading end portion of the needle thread. The holding member is movable to its thread release position after elapse of a second predetermined period at the initial start-up period of the sewing operation. The first predetermined period is within the second predetermined period.

Abstract: A device on a sewing machine for controlling the tensile stress (F) applied to a thread as it is being fed in the sewing process, including a device for producing a frictional force acting on the thread, a setting member, a force-measuring device, and a control unit for controlling the tensile stress (F) in the thread. The setting member functions commonly as the force measurement sensor and the force-applying device.

Abstract: A slackened needle thread assuring unit includes a thread tension member mounted on a side wall of a frame secured to the bed of a sewing machine. A thread takeup is positioned above the thread tension member. A needle/bobbin thread cutter is positioned apart from and under the frame for cutting a needle thread. A thread end holder holds an end of the thread to be cut by the needle/bobbin thread cutter. A thread guide extending across the front portion of the frame has one end supported by a support plate and the other free end defining a hook. A drive mechanism supported by the support plate reciprocally moves the hook in the direction substantially perpendicular to the threading direction of the needle thread.

Abstract: A method of supplying a thread to a sewing machine from a reel wherein the thread is supplied by carrying on a hanger a loop produced between the reel and the sewing machine by twisting the thread two to three times. The hanger used in supplying the thread comprises a case body, a cylindrical dial partly exposed on the surface of the case body, and a hook projecting from the case body to catch the thread. The hook is coupled through gearing to the dial and is rotatable in response to rotation of the dial.