Abstract: A bobbin case for a lockstitch sewing machine is disclosed which contains a thread control lever so constructed to allow the bobbin to be manually threaded from any direction without incurring the possibility of snagging the bobbin thread between the wall of the bobbin case and the thread control lever. One extremity of the thread control lever is pivotally mounted in a race formed in the wall of the bobbin case. The free extremity of the thread control lever, which is spring biased toward the bobbin, is shaped to form an obtuse angle with the wall of the bobbin case. Bobbin thread is thereby prevented from snagging between the bobbin case wall and the thread control lever.

Abstract: A device for preventing the rotation of the bobbin case member of a horizontally fully rotatable shuttle comprises a retaining member adapted to contact one portion of the inner shuttle member for retaining the bobbin case member against rotation. One of the contact faces of the bobbin case member and the retaining member is partly formed with a recess. The retaining member is reciprocally movable along the contact face of the bobbin case member to prevent the rotation of the shuttle member and permit release of an upper thread free of resistance.

Abstract: A thread handling system for a sewing machine is provided with elongate thread holding members formed for frictional contact of both members with thread during movement of the thread in the holder free of a takeup, and both formed and placed to cause thread in the thread holder to be pulled by the takeup away from one of the members and frictional drag on the thread holder reduced during movement of the takeup in the stitch setting direction.

Abstract: A bobbin thread control comprising a bobbin thread pull-off, carried by a rotating lockstitch looptaker to pull bobbin thread from a bobbin after the previous stitch has been set and having a retraction element variable in its rotational position on the looptaker for enabling selective retraction of bobbin thread from the setting stitch.

Abstract: A thread loop regulating arrangement is provided in a sewing machine having a reciprocated swingable needle carrying an upper thread and a loop taking arrangement including a rotatable loop taker, a bobbin carrier having a predetermined surface to receive thread loops and a bobbin positioned within the bobbin carrier. The thread loop regulating arrangement includes a relatively flat plate placed against the predetermined surface of the bobbin carrier and spaced therefrom and a downwardly extended lip for guiding the thread loop pulled off the bobbin carrier and thereby preventing the formation of undesirable stitches.

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 thread handling device is disclosed in a type 301 lockstitch rotary hook loop taker sewing machine having a three-to-one hook to arm shaft ratio for controlling and metering slack needle thread prior to needle penetration to prevent the thread from wrapping around the point of the needle, which could prevent loop seizure, break the thread, or interfere with correct stitch formation. The thread is guided between two stationary members, with the controller between the members, the controller comprising an edge attached to the needle bar drive connecting link, moving with it, and only engaging the thread as the take-up and needle bar descend, providing a lengthened thread path prior to needle penetration.

Abstract: A throat plate having means attached thereto for preventing the work limb in a loop of thread from being drawn up through the material being sewn by the take-up limb due to friction therebetween causing a loose stitch known as a halo.

Abstract: A bobbin thread tensioning device on a bobbin case is provided with a pair of bobbin thread accepting members, one of which is biased toward the other by an adjustable spring. The thread accepting members are disposed relative to each other and with respect to a rotatable hook to assure seizure of the bobbin thread by the hook beak.

Abstract: A throat plate having means attached thereto for preventing the work limb in a loop of thread from being drawn up through the material being sewn by the takeup limb due to friction therebetween causing a loose stitch known as a halo.

Abstract: An input gear and a hook driving gear in mesh with the input gear in the gear train for the hook of a sewing machine are rendered self-adjusting by having the input gear drive the hook driving gear through a key which is movable in one direction on an input shaft and with respect to which the input gear is movable in a direction perpendicular to said one direction, and by having the hook driving gear drive the hook through shaft affixed collar permitting movement of the hook driving gear transversely relative to a bushing upon which such gear is rotatably mounted.

Abstract: A lockstitch sewing machine is provided with a rotatable loop and bobbin case assembly providing for limited contact between the loop taker and bobbin case, and including a bracket which is affixed to the bed of the machine and is connected with the bobbin case at substantially diametrically opposite locations thereon to constrain the bobbin case angularly and rotationally but permit needle thread to be moved by the loop taker between the bobbin case and bracket during the formation of lockstitches.

Abstract: This invention relates to a needle guard which is adapted to position the needle relative the lower stitch forming mechanism and further serves to minimize skipped stitches during the sewing operation. The needle guard is positioned beneath the work supporting surface of the machine and during the sewing operation is disposed proximate the needle path. Upon completion of the sewing operation the needle guard is retracted from the path of the needle. Adjustable means are provided so as to accomodate the needle guard to needles of various sizes and to permit positioning of the needle guiding surface with respect to the path of the needle.

Abstract: A lockstitch sewing machine utilizing a needle looper to extend upwardly through a work material to grasp an upper thread and pull it downwardly through the work material to a looptaker which casts the upper thread about a lower thread in order to form a lockstitch. When the needle looper is in an upper position to catch an upper thread, a hook needle is exposed and thread is deflected into the hook thereof. As the needle looper is retracted to a depressed position the hook needle is moved to a guard position so as to retain the upper thread therein during transit. When the needle looper is at its lower position, the hook is again exposed to release its thread to a looptaker for concatenation with a lower thread.

Abstract: A throat plate having means attached thereto for preventing the work limb in a loop of thread from being drawn up through the material being sewn by the take-up limb due to friction therebetween causing a loose stitch known as a halo.

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: 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: A lockstitch sewing machine utilizing a needle looper to extend upwardly through a work material to grasp an upper thread and pull it downwardly through the work material to a looptaker which casts the upper thread about a lower thread in order to form a lockstitch. When the needle looper is in an upper position to catch an upper thread, a hook needle is exposed and thread is deflected into the hook thereof. As the needle looper is retracted to a depressed position the hook needle is moved to a guard position so as to retain the upper thread therein during transit. When the needle looper is at its lower position, the hook is again exposed to release its thread to a looptaker for concatenation with a lower thread.

Abstract: In a lockstitch sewing machine, a bobbin thread replenishing mechanism for selectively rotating the bobbin to wind replenishment thread thereon from a needle by means of a spindle selectively engaging the bobbin for rotating the bobbin with the machine looptaker wherein a slip clutch provided with an elongated slot is positioned around a flattened end portion of the spindle generally within a central aperture of a bobbin thread control cam. The slip clutch has an enlarged lower flange which rests on the looptaker base and rubs against the thread control cam so that by this arrangement the spindle will be driven with the looptaker by way of friction coupling of the slip clutch between the looptaker and the thread control cam. Should sufficient resistance of the turning of the spindle arise, the looptaker and thread control cam turn freely relative the slip clutch thereby preventing overwinding of the bobbin.

Abstract: In a sewing device for sewing fabric cuts on workpiece parts, which are moved by means of a workpiece clamping plate relatively to the needle of a sewing machine, a tiltably arranged and easily accessible vertical axis rotary looptaker for allowing replenishment of thread supply.

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 throat plate having a anti-haloing member attached thereto to separate the work limb of a loop of needle thread from the take-up limb during the setting of a stitch thereby preventing the work limb from being drawn up through the material being sewn by frictional interengagement with the take-up limb.

Abstract: A shuttle device provided with a rotating hook comprises a rotatable race secured to a verticle driving shaft. A bobbin carrier is journalled in the race and has a pair of spaced abutment faces on opposite sides of the path of the needle. The abutment faces cooperate with two spaced beaks on an oscillating escapement so that one of the beaks is always in contact with one of the abutment faces to prevent the carrier from rotating. The oscillation of the escapement permits a space to be left alternatively for each pair of cooperating beaks and abutment faces for the passage of the upper thread loop. The escapement is resiliently yieldable to prevent injury to the beaks or abutment faces, in the event of thread jamming between the sliding contact faces of the shuttle race and the bobbin carrier.

Abstract: An improved mechanism for producing blind stitches with a household sewing machine, including a removable throat plate having a thread deflecting member reciprocatorily driven into engagement with a loop of thread carried by the loop taker to insure engagement of the loop of thread by a hook needle. The thread deflecting member is driven in timed relation to the rising and falling motion of the feed dog by a cam which is fastened to the feed drive shaft.

Abstract: A sewing machine having a semi-rotating looper assembly, characterized in that the driving mechanism for said semi-rotating looper assembly comprises a motor, a rotatable link, and a sector gear formed on said rotatable link. Said sewing machine further comprises a cloth-feeding mechanism including cloth-feeding teeth, a spring for biasing said cloth-feeding teeth in one direction and to a level below the plane of the cloth to be fed, and a swingable lever connected to said link. Said semi-rotating looper assembly includes a rotating looper holder opening in the table surface of the machine body, a slit formed in the inner peripheral wall of said rotating looper holder, and a rotating looper disposed in said rotating looper holder and having a bobbin holding portion and an edge. Said looper assembly further includes a driving mechanism for causing a partial reciprocatory rotary motion of said rotating looper within said rotating looper holder.

Abstract: Work feeding mechanism and a rotatable loop taker are provided for a sewing machine in a module wherein a rock shaft connects with a feed bar through a flat spring enabling a feed dog on the feed bar to be moved by camming means in a direction perpendicular to the work feeding direction as the feed dog is moved in the work feeding direction by the action of the rock shaft. The camming means which is disposed under the feed bar is located in line with the feed dog to minimize inertia effects and guiding means associated with the feed bar maintain the feed dog level as the feed dog is moved in the work feeding direction and perpendicular to it.

Abstract: A lock stitch sewing machine is provided with mechanism operable by a feed dog for pulling thread for stitches from a bobbin spool in amounts predetermined by the setting of a stitch length regulator.

Abstract: This disclosure relates to hook drive mechanisms for sewing machines and in particular to a hook drive mechanism wherein the hook member is freely supported by a bearing means in a hook support plate carried by the bed portion of the frame and is driven by a likewise freely supported drive member. The support plate with the hook member is supported for relative adjustment with the needle for adjusting the hook point-to-needle relationship. The hook member is readily removable in that it is freely supported in the aforementioned bearing means and is otherwise only restrained by a movable restraining means carried by a hook member cover plate which when removed from restraining relationship permits the bobbin and the hook member to be easily lifted out from the machine. Further, means are carried on the hook support plate for adjusting and maintaining tension on a timing belt drive means for the hook mechanism.

Abstract: A loop taker mechanism and bobbin carrier for a sewing machine in which the bobbin carrier is formed of three components and is journalled in a rotary hook casing. An oscillating escapement yoke has two spaced beaks which cooperate with abutment faces on the carrier to prevent the carrier from rotating. One of the beaks carries an over-hanging guide plate which is wider than the beak and serves to prevent a thread loop from moving behind the beak and fouling the operation of the machine.

Abstract: This disclosure relates to sewing machines and in particular to a means for reducing uneven and slack stitching due to frictional engagement between the work limb and the takeup limb of the needle thread which can cause pulling up of the work limb through the fabric between castoff of a loop from the loop taker and stitch setting. This undesirable effect is sometimes called "haloing". A work limb retainer is provided and is carried apart from the loop taker and thread carrying bobbin and is disposed for seizing the work limb of the needle thread substantially immediately after loop seizure by the loop taker, retaining of the work limb during the normal loop taker cycle, and discharging the work limb after the thread has completed its passage around the loop taker. The work limb is thereby prevented from frictionally engaging the take up limb during this cycle and thus eliminates the possibility of the take up limb pulling the work limb up to the fabric to cause a haloing effect.

Abstract: A bobbin thread pull-off, attachable to a rotating lock-stitch looptaker in a location to pull bobbin thread from a bobbin after the previous stitch has been set. The pull-off and attachment means are given a thread handling finish prior to assembly to a completed looptaker, no other finishing operations being required after assembly thereto.

Abstract: An improved lockstitching mechanism for a sewing machine wherein the cylindrical bobbin case having a bobbin therein for supplying a lower thread has an upper thread guide for slidably guiding a loop of the upper thread across the lower thread and a lower thread guide hole in the side wall below the upper guide for guiding the lower thread being extracted from the bobbin, whereby the lower thread is placed ahead of the needle relative to the rotational direction of the shuttle body supporting the bobbin, such that the upper thread only crosses the lower thread once during each stitching operation to prevent gnarling of the seam commonly referred to as "hitchstitching".

Abstract: This disclosure relates to means for providing adjustment of the needle to hook point relationship in a sewing machine without disturbing the proper mesh and timing of the gears used in the drive mechanism for the hook. The hook includes a shaft supported in a bushing which has a bore having an axis eccentric to the axis of the bushing body. An interposer member is operatively connected to the drive mechanism and is disposed coaxially with the hook shaft for transmitting driving motion to the hook shaft. The hook point is adjustable relative to the needle by means of rotation of the hook bushing about its axis which thereby changes the relative position of the hook and its shaft without causing any change in the relative driving relationship of the interposer and the drive mechanism thereby unaffecting the timing of the hook drive mechanism.