Abstract: A handwheel clutch for a sewing machine having a bistable tiltable element for engaging or disengaging the clutch thereby coupling or decoupling the handwheel from the arm shaft.

Abstract: A handwheel and handwheel clutch assembly for a sewing machine having a bistable tiltable element for engaging or disengaging the clutch thereby coupling or decoupling the handwheel from the arm shaft.

Abstract: A sewing machine bobbin case is provided with a thread tensioning device that includes a pivotally movable arm which is spring biased into a position preventing thread from entering the device during the sewing of materials on the machine, but which is disposable by a finger in a position providing for the introduction of thread into the device in preparation for the performance of a bobbin winding operation.

Abstract: A thread engageable finger for guiding needle thread into a thread receiving slot on the bobbin case of a sewing machine, as a seized loop of the thread is moved about the bobbin case by a looptaker, is provided along a thread engaging edge with a predetermined curved contour effective to delay movement of the thread along said edge until the introduction of thread into the bobbin case slot as required for bobbin winding is assured.

Abstract: A winding device for a sewing machine including a sewing mechanism connected to a machine drive mechanism, by a coupling which comprises, a sewing machine housing, the winding device being movable to swing into the sewing machine housing and be covered by a lid when not being used. A two-armed hinge support is pivotally disposed on the housing and connected to the lid. One arm of the said two-armed hinge support is connected by a lever mechanism with a support, and the support is pivotally attached to the sewing machine housing for the winding device forming a toggle joint such that when the lid is opened the toggle joint is pushed through and the winding device is brought into its operating position and secured there while the other arm of the two-armed hinge support disengages said coupling between the machine drive mechanism and the sewing mechanism.

Abstract: A control arm for bobbin winding mechanism in a lockstitch sewing machine is provided with a pawl which serves both to guide needle thread into a thread entering slot for a tensioning device on a bobbin case, and to hold an arm of the tensioning device in a position effective to prevent the thread from being pulled out of the slot.

Abstract: A bobbin resting on a bobbin case in the vertical axis looptaker of a sewing machine is provided with a slidable plunger which is biased into a position wherein the bobbin is disconnected from the looptaker and can rotate relative thereto. The plunger is depressable to a cam on the plate into a position wherein it is effective to cause the bobbin to be rotated with the looptaker for the winding of thread.

Abstract: A device for automatically supplying thread to the bobbin of a sewing machine of the kind wherein there is a thread feed tube arranged to receive the thread from a bulk source, a predetermined length of the thread is delivered to a rapidly rotating bobbin for winding of the thread thereon and then the thread is severed from the source.

Abstract: A sewing machine is provided with a spring biased platform and bobbin which are movable by the throat plate of the machine into a position wherein the bobbin is disposed to receive the lower limb of a loop of needle thread and to effect an operative connection between the bobbin and drive shaft providing for rotation of the bobbin as required for bobbin winding. An electrical switch operable by the thread of a full bobbin is provided to discontinue rotation of the bobbin drive shaft.

Abstract: Thread-loading apparatus for loading a bobbin spool with a predetermined length of thread between sewing operations wherein there is a reciprocal loading tube arranged to receive and draw thread from a package of thread, deliver its leading end to the bobbin and project it onto the bobbin while the latter is being rotated at a high speed so as to be caught thereby and wound onto the bobbin; a slack-producing device for drawing a slack length of thread from the package of thread preparatory to a loading operation to thus eliminate the inertial resistance of the package of thread to giving up thread; a precisely-controlled thread measuring device employed to control the length of thread delivered to the bobbin; and a bobbin having peripherally-spaced flexible fingers on its hub for entraining the leading end of the thread delivered to the bobbin.

Abstract: An automatic bobbin winding system for lockstitch sewing machine having the capability to wind needle thread around said bobbin while said bobbin is supported within the looptaker of the sewing machine wherein a depleted condition of the bobbin is sensed causing the work feed system to be disconnected, the bobbin winding system to be enabled and endwise reciprocation of the needle bar to be suspensed after needle thread is introduced into the bobbin winding system in order to fully wind the bobbin supported within the looptaker. When the bobbin is completely wound, a full bobbin sensing device is activated which terminates the bobbin winding, reinitiates the work feeding system and the endwise reciprocation of the sewing needle in order to continue stitching at that point where bobbin thread depletion was first sensed.

Abstract: A thread guiding system for sewing machine bobbin winders in which the last thread constraining eyelet is positioned laterally centrally of the bobbin spindle and a plurality of smooth surface guide pins are positioned between the thread constraining eyelet and the bobbin with the axis of each pin parallel to that of the bobbin spindle. The pins exert no lateral influence on the thread which is allowed to move freely along the pins. With this construction the distance from the last thread constraining position to the bobbin is greatly reduced from that normally required for smoothly winding thread uniformly about the bobbin.

Abstract: A mechanism for coupling and uncoupling a driven rotatable drive wheel from a rotatable shaft, particularly, the arm shaft of a sewing machine from its associated drive wheel in order to spool up the lower thread, comprises a rotatable shaft which has an annular collar portion which is frictionally engageable by a drive wheel which is freely rotatable on the shaft. The drive wheel is continuously driven from a drive, such as a belt, and it may be urged into engagement with the collar by means of a nut which is threaded onto the end of the shaft. The arrangement includes a stop disc which has a cam surface which is engageable with a stop defined on the nut end face in a recess thereof. The cam surface and the stop define a cam structure which permits rotation of the nut so as to permit frictional engagement of the drive wheel with the shaft collar for driving the shaft and the disengagement thereof by rotation of the nut in a reverse direction.

Abstract: A thread winding mechanism including a thread winding shaft and a clutch member for disconnecting a torque transmission between a main shaft of a sewing machine and a drive pulley. Once the bobbin is manually inserted into the thread winding shaft the clutch member is automatically actuated to disconnect the main shaft from the drive pulley for preparation of the thread winding operation.

Abstract: The disclosure relates to the automatic refilling of a bobbin spool, in a lock stitch type sewing machine, in the interval between the loading of work units. After sewing of a predetermined work unit, consisting of a single workpiece, or several workpieces, a premeasured thread length on the bobbin spool is exhausted. While the machine operator places a new work unit in position for sewing, the mechanism of the invention refills the empty bobbin spool, in situ, with a precisely measured length of bobbin thread, drawn from an effectively continuous supply source. The mechanisms provided for this purpose, in and of themselves generally known, are arranged in an improved, simplified and more compact arrangement, suitable for incorporation in a variety of commercial lock stitch type sewing machines available to the trade.

Abstract: The device is incorporated in a sewing machine having an arm enclosing and rotatably mounting an arm shaft connected to the sewing mechanism, a drive wheel rotatably mounted on the arm shaft and driven in any suitable manner, and a thread winder including a wheel selectively engageable with the drive wheel. A clutch ring surrounds the arm shaft and is pivotal on a pin extending diametrically of the arm shaft, the clutch ring having a trapezoidal engaging cam engageable in trapezoidal recesses in the drive wheel. A flat spring biases the clutch ring normally to couple the drive wheel to the arm shaft. When the thread winder is moved into a position adjacent a fixed stop, a release stirrup engages the clutch ring and pivots it to a position disconnecting the drive wheel from the arm shaft. Another spring biases the release stirrup away from the clutch ring.

Abstract: A thread winding mechanism for a sewing machine head includes a main drive shaft for operating the sewing components and which is rotatably mounted within the head of the machine, a flywheel rotatably mounted on the drive shaft, a clutch for connecting and disconnecting the flywheel from the drive shaft, and a motor for driving the flywheel. A thread winding shaft is formed integrally with and extends axially outward from one end of the flywheel to the exterior of the head and a clutch operating handwheel mounted on and rotatable with the flywheel and which likewise extends outside the head can be shifted axially between an inward position wherein the flywheel is disconnected from the drive shaft and the thread winding shaft is exposed, and an outward position wherein the flywheel is connected to the drive shaft and the thread winding shaft is concealed within the handwheel.

Abstract: A sewing machine has a housing and a needle displaceable on the housing between a down position engaging through a workpiece and an up position disengaged therefrom. A drive is connected to a drive wheel rotatable on a drive shaft in the housing that in itself is operatively connected to the needle. A clutch including a clutch member on the shaft between the shaft and the wheel has a control element displaceable between an engaged position for rotationally coupling the wheel and the shaft and a disengaged position for free relative rotation of the wheel and the shaft. Thus in the engaged position of the clutch the drive can vertically reciprocate the needle between its up and down positions. A stopper member having an engaging part is mounted on the shaft and a stopper is mounted on the housing.

Abstract: A sewing machine motor is connected to a drive wheel which can be connected via a clutch to a drive shaft that vertically reciprocates the sewing-machine needle. A cam on the shaft and a stopper on the housing are displaceable between an operative position engageable with each other for stopping rotation of the shaft in a predetermined angular position corresponding to the up position of the needle and an inoperative position unengageable with each other. A cam is provided for displacing the control element of the clutch from an engaged to a disengaged clutch position on engagement of the stopper in its operative position with the cam so that the shaft can be arrested in a predetermined angular position and is substantially simultaneously rotationally uncoupled from the wheel.

Abstract: A sewing machine operated by a foot controller is provided with a mechanism for stopping the main shaft of the sewing machine in a predetermined position of each revolution thereof, thus to intermittently drive the sewing machine to produce intermittent stitches. The mechanism can be made inoperative allowing the main shaft to continuously rotate, thereby to produce the ordinary continuous stitches.