Abstract: A sewing control system for a sewing machine which comprises a count circuit for counting signals synchronized with the rotation of the sewing machine, a memory circuit for storing a reference value, a comparator circuit for comparing said reference value with the output value from said count circuit, an initializing circuit for initializing said count circuit only when there is a comparison output from said comparator circuit after said reference value is stored, and a circuit for outputting a sewing finish signal as data on the number of the works sewn only when there is a comparison output.

Abstract: A thread cutting device for a lockstitch sewing machine having a rotary hook rotating in a horizontal plane, comprises a thread catcher which is pivotable in a horizontal plane and designed with a catch shoulder for needle and bobbin threads. The catcher cooperates with a stationary cutting tool as well as with a leaf spring which serves as a clamp for the end portion of the bobbin thread. The thread catcher is designed with a retaining shoulder by which the needle thread loop, upon being passed around the bobbin case, is caught and then released before being cut. The temporarily retained thread length substantially corresponds to the thread length which is pulled out sidewards while the thread catcher moves into its cutting position. Since no needle thread is thereby pulled off the thread supply by the thread catcher, only a minimum force is needed for moving the catcher.

Abstract: A thread cutting device for a double lockstitch sewing machine is provided with a rotatably driven hook including a hook beak for seizing a needle thread loop. In order to assure a safe pickup, the thread catcher performs an operating movement in a tilt direction oppositely directed with respect to the direction of rotation of the hook. Furthermore, the thread catcher is operable if the hook point has passed the stitch hole for a range of about 90.degree. considered in the direction of rotation of the hook.

Abstract: A device for stopping the machine drive of a needle movable in cooperation with a rotary hook of a sewing, embroidering or tufting machine upon a thread breakage comprises a thread cutting mechanism which includes a thread catcher movable through the needle path and a switching mechanism which is connected to the drive for disconnecting it and which becomes effective upon a thread breakage. The device includes a movably mounted thread feeler carrier having a thread feeler which is adapted to be located between the needle and the rotary hook. The drive mechanism for actuating the thread catcher includes control cams which are engageable with lifting cams so as to project the feeler out of the path of motion of the thread between the needle and the rotary hook. The thread feeler is associated with a piezoelectric element and the deflection of the feeler by the thread produces a pulse which regulates the drive mechanism for the sewing machine and effects the stopping thereof when the threads are cut.

Abstract: A computer-controlled automatic sewing machine has a sewing head and a workpiece holder. In order to be able to alternately sew at least two workpieces, the sewing head is movable in X and Y-directions by means of servomotors, while the workpiece holder having at least two workpiece clamps is fixed.

Abstract: The specification relates to accessory device to be used in conjunction with a sewing machine having an automatic thread cutter. The accessory device is provided for enlarging the passageway between the sewing foot and the stitch plate, to enable bulky articles to be moved within said passageway at the time the thread is cut. The device includes a push-back mechanism comprising brake jaws as engaging elements acting upon the drive and mounted on an entrainer operationally connected with an activating device for the purpose of engaging the drive by means of said engaging elements, to push it back and bring the needle bar into its upper position, while the thread feeder remains in its lower position. The obtainable increase in the height of the passageway may be as high as 30%.

Abstract: A thread cutter for a zig-zag sewing machine which has a needle which swings transversely to the material feed direction to form a zig-zag seam of predetermined width while the needle is reciprocated to pierce material to be sewn in cooperation with a revolving looper as the material being sewn is moved transverse to the swing direction and includes a cutting knife which cooperates with a movable catcher which is moved in time relationship to the rotation of the looper. The catcher is a plate-like member having an end terminating in the tip and a lateral edge on each side of the tip with one lateral edge having a first barb for engaging one leg of the needle thread loop and an opposite lateral edge having a second barb for engaging another leg of the needle thread loop, the one leading directly to the needle.

Abstract: A thread cutter assembly in a sewing machine having a thread cutting cam which is driven by an opener shaft operated in response to the rotation of the rotary shaft of a rotary hook assembly. A movable edge is coupled to a cam follower engageable with the thread cutting cam. The engagement and disengagement of the cam follower and the thread cutting cam are controlled by a control mechanism to carry out a thread cutting operation.

Abstract: An automated thread trimming apparatus is provided for use with a sewing machine having a plurality of needles. The apparatus is mounted on the side of the sewing machine away from the sewing machine operator. A pair of blades is provided for each needle of the sewing machine. The blades are adjustably mounted on blade mounting bars. Upon actuation, the blades are positioned to straddle each array of stitches produced by the sewing machine needles. The blade mounting bars are then moved slidably relative to one another so that each pair of blades severs an array of stitches. The blade mounting bars are then moved away from the work table of the sewing machine allowing the next workpiece to be sewn.

Abstract: An industrial sewing machine system having a thread trimmer is provided with an arrangement which generates a signal when the thread is 180.degree. from the needle. At this time, the thread picker is actuated and during the time required for the picker to be properly positioned, the control circuitry for the system is disabled.

Abstract: A solenoid operated sewing machine thread trimmer with a compression spring influenced armature, a spring offsetting permanent magnet, and solenoid coil means with energizing circuits alternately offsetting the permanent magnet freeing the compression spring to shift the armature in one direction or augmenting the permanent magnet to return the armature.

Abstract: An automatic thread trimmer for use on a computerized embroidery sewing machine having a work table, a bobbin mechanism below the work table, an arm overhanging the work table with a needle driver therein movable through one cycle for each cycle of operation of the sewing machine needle, and a computerized control connected to the machine for driving the needle driver and shifting the needle according to the computer program.

Abstract: A thread cutting device applicable to sewing machines includes elements connected to a support plate to be installed in the sewing machine at the position therein where the common sliding elements are to be located. The support plate has a screw which acts on a bridge element when the bridge element is pressed against the lower face of a panel of the machine. One of the elements of the thread cutting device has a generally Y-shaped configuration and is provided with an alternating lineal movement, either by means of manual, electro-pneumatic or electromagnetic operation, in directions parallel to that of the sewing of the machine. Such shaped element angularly operates a movable knife against a fixed knife in synchronized cooperation with a thread collecting hook which also has an angular displacement. The arrangement further includes a thread withdrawing device and a thread tension opening device.

Abstract: Herein disclosed is a below the throat plate thread trimmer which is moved in a path from the right side of the rotary hook assembly, up and over it and then downwardly to the left of it. The path being in the nature of a compound angle whereby elements of the thread cutter portion pass into the needle thread loop at a most advantageous angle. After securing and separating the bobbin thread and respective legs of the needle thread loop, the thread trimmer is moved to position directly below the needle hole. While in this position the bobbin thread and one leg of the needle thread loop are cut.

Abstract: An underbed thread trimmer mechanism for severing the needle and bobbin threads upon completion of a sewing operation. Operation of the thread trimmer may be selectively initiated by operator command. A plurality of cams and members cooperate to transfer power from a loop taker shaft to a thread handling disc-like member situated in close proximity to the sewing machine loop taker. A thread cutting knife is disposed in covering relation to the thread handling member and cooperates with the thread handling member to trap the needle and bobbin threads and direct them to a knife surface of the thread cutting knife where they are severed. The mechanism that drives the thread trimmer resets itself at the completion of the thread cutting cycle.

Abstract: An apparatus for controlling an electric sewing machine has a mechanism for transmitting the driving torque of a motor to the sewing machine to drive the same, a mechanism for imparting braking power to the sewing machine to stop the same, a mechanism for stopping the needle of said sewing machine at desired positions in its stroke and controlling means adapted to control these mechanisms. At least a part of the controlling means is constituted by a microcomputer. The signal input to the microcomputer is provided in synchronization with a synchronizing clock signal, and only such input signals as required in respective periods of operation are checked in each of the periods, so that the checking of the input signals is facilitated and accidents due to erroneous operation are avoided.

Abstract: A cutting apparatus for cutting a strip of tape connected to a shoe upper component and extending beyond the edges thereof includes a blade for cutting the tape and presser feet for tensioning the tape during cutting. The blade and presser feet are independently actuated by plungers, which are slidable in a casing mounted on the sewing machine used to sew the tape onto the upper component. The plungers are provided with magnetic cores, and separate coils around the cores are energized in response to signals from photosensors in the work surface of the sewing machine to effect tensioning of the tape, followed by cutting at the edge of the upper component. Springs in the casing around the plungers return the plungers to a rest position, and the tape tensioning and cutting operations are repeated at each component edge.

Abstract: A driving mechanism for actuating an underbed thread trimmer in a post-type sewing machine. The unit is selectively controlled by a solenoid and actuated by two cams located on the hook shaft of the feeding post. Rotary motion of the shaft and cams is converted into translational motion for the trimmer by a pivoting swivel lever and cam follower combination.

Abstract: In a protective device for controlling a sewing machine at a predetermined number of revolutions by a motor equipped with a clutch mechanism and a brake mechanism which are electromagnetically actuated, a protective device is constructed comprising a detector to detect substantially the rotation of the driving shaft of the sewing machine, and a detector to detect the voltage of a control circuit with an output from the detectors being compared with a reference value representative of a predetermined driving state for the sewing machine, so that when the output of the detector becomes lower than the reference value, the operation of the control circuit is terminated, whereby safe operation is provided for the apparatus and an operator.

Abstract: The sewing machine includes a reciprocating needle bar with a thread-engaging needle which cooperates with a rotatable looper carrying the looper thread which is driven by a rotatable looper drive shaft. The construction includes a thread knife and a thread clamp mounted adjacent the looper and a catcher mounted on a catcher shaft for rotation therewith selectively in the same direction of movement as the looper toward engagement with the knife and in an opposite return direction. The construction includes an improved control member for operating the catcher which is freely rotatable on the looper shaft and is axially displaceable therealong between an operative position and an inoperative position spaced axially from the operative position. A coupler is provided between the control member and the looper shaft which includes a driver having a rod portion which extends in a groove of the control member. A biasing spring biases the control member into an operative position.

Abstract: In a control circuit for controlling the rotating speed of a clutch and brake motor of a sewing machine capable of performing non-ravel seaming, an improved non-ravel seaming controller for enabling non-ravel seaming during a certain number of seams at the start of sewing and for generating a medium speed signal at a predetermined level during a certain number of seams at the end of sewing to enable non-ravel seaming at such time.