Abstract: A thread take-up arm drive means for a multihead embroidery machine in which identical heads have automatic color change capability such that the color thread stitched on the plurality of embroidery heads is changed substantially simultaneously. A sliding carriage associated with each head contains a plurality of associated color stitching sets of thread take-up arms and needle bars. Each color stitching set is for stitching a different color thread. A computer controls a step motor to position the carriage and thus place the particular color stitching set in contact with the drive means. The thread take-up arm drive means is a pushplate biased in an up position by a leaf spring having adjustable tension. A cam follower is attached to the pushplate and moves the pushplate cyclically under force of and according to the design of the periphery of a cam. The cam is attached to the drive shaft that drives both the thread take-up arm and the needle bar of a color stitching set.

Abstract: A thread changing mechanism for sewing machines comprises a plurality of needle holders which are received for displacement in a magazine which is fixedly mounted at the level of the top dead center of the needle bar. The needle holders have inner guide surfaces in T-configuration, corresponding to outer T-configuration guide surfaces of the coupling member which is secured to the needle bar. In the middle of the magazine, a recess is provided for the coupled needle holder. In a first embodiment, several fingers are pivotable between the needle holders to space them from each other. The coupled needle holder can then move freely upwardly and downwardly during the sewing operation. In a second embodiment, the same free movement of the coupled needle holder is ensured by a fork by which, after the coupling is effected, the needed spacing between the coupled one and the adjacent needle holders is ensured.

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 device for driving a sewing machine which includes a main shaft driven by a positioning motor that can be stopped in at least one predetermined position and then returned back to a second predetermined position, comprises a coupling disc which can be moved into engagement with a drive disc associated with the motor and a main shaft to drive the main shaft in a direction opposite to its normal direction of operation as determined by the positioning motor. The coupling disc is provided with cam surfaces with a cam engaging surface provided on a supporting member which is biased toward the disc by a predetermined tension. An actuator is connected to the support for rotating the actuator. The initial rotation moves the coupling disc into engagement with the driver disc which is connected to the main shaft, and the further rotation of the support rotates both the coupling and main shaft by a predetermined amount.

Abstract: A method for implementing winding of a lower thread bobbin in place in a looptaker of a sewing machine from an upper thread supply. A buttonhole pattern in which at least one initial stitch is effected at one end of the buttonhole prior to holding needle bar reciprocation in abeyance while feeding the work material to the other end of the buttonhole, is selected but is utilized without a traveling buttonhole foot which would reinitiate stitching and feeding of the work material. Instead, any other presser foot, or no presser foot, is used so that bobbin winding may proceed after upper thread is initially brought to the lower bobbin, without having thread flow interferred with by needle bar reciprocation.

Abstract: A device for driving at least one needle bar on embroidery or sewing machines from a main drive shaft by means of a crank drive. In order to create a simple construction of high efficiency, low noise and little wear, the axis of rotating of the crank mechanism is arranged parallel to the main drive shaft. The bearing for defining the axis of rotation of the crank mechanism is adjustable in height such that the magnitude of the stroke of the needle is unchanged.

Abstract: An embroidery machine having a plurality of embroidery bars, particularly needle and piercer bars, which are mounted for axial displacement independently of each other and arranged in at least one row alongside of each other, which bars can be coupled individually with a reciprocating drive element in accordance with a program determined by a control. In order to be able to couple each individual embroidery bar with the drive element in accordance with any desired unlimited number of programs without having to stop the drive in order to change the program, each individual embroidery bar can be coupled with the drive element by the force of at least one magnet.

Abstract: In a multiple needle sewing machine having a plurality of needle bars and a block member to which they are moveably mounted, a lever device can be located at any one of a plurality of positions corresponding to that of a specific needle bar. During transfer of the lever from one position to another, the block member is moved across the feeding line of a workpiece to be sewn and another needle bar corresponding to another lever position is brought into operative connection with a crank.

Abstract: Disclosed herein is waiting means for use in an embroidering machine which has a head; a needle bar vertically movably carried in the forward end portion of the head and having a needle operatively connected thereto for forming embroidery stitches on a cloth; a nipple vertically movably carried in the forward end portion of the head in parallel relation with the needle bar, the nipple slidably receiving the needle bar therewithin and adapted to be lowered synchronously when the needle bar is lowered so as to press the cloth at the needle location where the needle passes through the cloth; and a presser foot vertically movably carried in the forward end portion of the head in parallel relation with the needle bar and the nipple, the presser foot, when the needle is raised, being adapted to be displaced horizontally so as to horizontally feed the cloth while pressing the cloth around the needle location.

Abstract: A non-rotatable, disc-like bobbin carrier is nested in a cup-shaped, vertical axis, rotary loop taker that slidably supports the bobbin carrier at its periphery on an annularly extending, discontinuous lip constituting a circular race slightly offset eccentrically from the loop taker axis of rotation. As the loop taker rotates, the eccentrically positioned bobbin carrier jogs back and forth in reciprocating fashion against one and then the other of a pair of diametrically opposed fixed stops that cooperate to preclude rotation of the bobbin carrier. The movement of the bobbin carrier away from and against each stop is synchronized with movement of a thread loop about the bobbin carrier to permit free passage of the loop between the fixed stops and the moving bobbin carrier.

Abstract: An apparatus and method for implementing bobbin winding in place in a looptaker of a sewing machine. When a presser foot lift lever is manipulated to elevate a presser foot, and the sewing machine motor is activated, a series of two or three endwise reciprocations of the sewing machine is effected to bring an upper thread to the lower thread carrying bobbin, after which further endwise reciprocation of the sewing needle is held in abeyance while actuation of the sewing machine motor is continued, to provide the least disturbance of upper thread passage to the lower thread bobbin. No other bobbin winding signaling steps are required.

Abstract: A basting stitch mechanism in which a latch is carried on the side of the needle bar carrier and is fashioned with a front portion extending in front of the needle bar terminating in a wedge, which wedge fits into a notch in a driving stud hinge pin extending about the needle bar and slidable thereon. The latch wedge connection to the driving stud eliminates the requirement for establishing a clearance between the needle bar carrier and the driving stud carrying the driving stud hinge pin. An extension spring connected between the sewing machine frame and a rear portion of the latch operates to increase the latching force as the needle bar is moved downwardly. By proper design of the wedge on the latch and the notch on the driving stud hinge pin, separation of the driving stud hinge pin from the latch may take place at some force designed to avoid breakage of the sewing needle.

Abstract: A sewing machine having two needles supported in a needle holder, which needle holder is horizontally displacable, to present one needle to an active workstation in a prethreaded manner and simultaneously shift the other needle which has a different thread therein, into an adjacent inactive position. As the needles are being shifted, the needle moving to inactive status has its thread clamped against the needle holder by a wheel, to secure the thread from being pulled therefrom or straying. A vacuum tube arranged at each respective inactive position or station sucks the tail of the thread therein. A pair of thread guides, one for each thread, are arranged for vertical movement, to pullback on the dangling thread of the inactive needle, to prevent the thread from whipping during its inactive status. Each thread passes around a thread engaging wheel comprising a dual bobbin monitor arranged on a single axis.

Abstract: An automatic sewing machine is provided with a workpiece feeding device for imparting a continuous motion to the workpiece during the sewing cycle and with a sewing head having a needle bar which is oscillatorily driven by an arm shaft via a crank gear. In order to reduce the needle deflection due to the continuous workpiece feed motion in a simple way, in addition to the crank gear for driving the needle bar, there is interposed a double crank gear between the arm shaft and the crank gear which reduces the angle of rotation while the needle penetrates the workpiece.

Abstract: A device for temporarily interrupting the movement of the embroidery needle on an automatically controlled embroidery or sewing machine has at least one needle driven by a connecting rod and a crank from a drive shaft. On this needle bar there is fastened a driver which can be coupled via a shift pawl developed as double-armed lever with a drive carriage which is pivotally connected to the connecting rod. While one arm of said lever cooperates with a catch developed on the drive carriage, another arm of the lever cooperates with a controllable holding pawl by which the needle bar can be held fast in an upper dead-center position with simultaneous disconnection from the drive carriage.

Abstract: A sewing machine provided with three selectively operable needle bars and a take-up lever mounted for vertical oscillating movement is provided with a selectively operatable thread clamping device for selectively clamping any two of the three threads associated with the respective needle bars in a stationary position while permitting the third thread to follow the oscillating movement of the take-up lever during reciprocation of the selected needle bar. The thread clamping device is comprised of two flexible plates disposed between two stationary plates secured to the sewing machine arm. The four plates are provided with vertically aligned slots to accomodate the oscillating movement of the take-up lever.

Abstract: Needle bar drive in a sewing machine comprising a crank driven by a connecting rod provided on the main shaft for transmitting reciprocating motion to the needle bar and by a rod connected to the needle bar gate and driven by a linear motor in order to impart to the needle bar transverse movements relative to the sewing direction. A joint type connection between the connecting rod and the needle bar is provided in order to allow a smooth rational operation to the assembly.

Abstract: Skip stitch mechanism for a sewing machine is provided with a coiled cushioning spring which mounts on the upper arm of a movable gate, and limits upward movement of a needle bar when disconnected from needle bar reciprocating mechanism to provide for a skipped stitch.

Abstract: A positioning device for a mechanical switching lever arrangement in an embroidery machine comprises an electromagnetic device which serves for displacing a pawl lever between a first end position and an intermediate position. The pawl lever serves for actuating a switching lever arrangement. The positioning device further comprises a mechanical amplifier device for displacing the pawl lever between the aforementioned intermediate position and a second end position. At its free end region the pawl lever carries a permanent magnet which continuously adheres to the electromagnet when the same is deenergized. The mechanical amplifier device, which cooperates with the pawl lever, comprises an externally actuatable switching lever arrangement. By pivoting this switching lever arrangement the pawl lever can be displaced from its intermediate position to the second end position and vice versa.

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.

Abstract: Skip stitch mechanism for a sewing machine is provided with a coiled needle bar cushioning spring which mounts in axial alignment with the needle bar on the upper arm of a movable gate and which can be adjustably positioned on the gate arm to define a position from which the needle bar may be latched to reciprocating drive means.

Abstract: A needle positioner for a sewing machine having a shaft connected to a main drive motor to move a sewing machine needle reciprocally by a stitching operation which includes a crank rotatably supported on a frame drivably connected to the sewing machine shaft with a plurality of pneumatically actuated cylinder/piston assemblies, the pistons of which are engagable with the crank to move the crank and therefore the shaft through predetermined rotary angles together with a plurality of conduits having valves including control valves therein which are adapted to communicate the cylinder/piston assemblies with a source of pneumatic pressure so that selective actuation of the control valves produces rotary movements of the crank through the appropriate cylinder/piston assembly to move the needle into either a top or bottom position.

Abstract: A needle thread guide device containing an articulated thread feeder oscillating in a vertical plane on a sewing machine provided with a skip stitch mechanism working at intervals to form stitches of varying lengths, wherein a thread catcher is combined with a thread lever which can be engaged and disengaged synchronously with the skip stitch mechanism and which aligns in its operating position with a hook eye open to the top at a position of the upper area of the ascending movement part of the thread lever eye with the latter, thereby catching the thread loop which is carried along by the thread lever.

Abstract: A gap stitch mechanism for a sewing machine containing a needle shaft which is oscillatingly driven by a crank assembly, wherein the crank assembly is provided with means for reducing the crank radius at predetermined intervals during the sewing operation, thereby determining the stroke of the needle shaft and making it impossible for the loop catcher to catch the needle thread.

Abstract: The present invention relates to a device for displacing the color-change carriage on multiple-head embroidery machines having a plurality of embroidery needles per head which can be coupled alternatively with the needle bar drive for change in color or thread, the needle bar carriers of all embroidery heads being laterally displaceable jointly by a displacement bar which is connected with the color-change carriage. In order to create a dependably operating as well as easily mounted displacement device with the use of only a few individual parts, a control bar (10) which is provided in rack-like manner with incisions (10a) is arranged on the color-change carriage (6), a crank pin (11) driven by a servomotor engaging in said incisions (10a) and upon its engagement in an incision (10a) swinging a locking lever (12) on which there is arranged a locking member (14) which cooperates with the incisions (10a) and, via the control bar (10) positions the color-change carriage (6) in its corresponding position.

Abstract: A thread changer for an embroidering machine, having a plurality of needles for different threads, comprises, a driving shaft, a plurality of thread levers loosely mounted on the driving shaft, a coupling element for each thread lever connected to the driving shaft and rotatable therewith, and a clutch member connected between the drive shaft and the thread levers for coupling a selected one of the thread levers to the drive shaft to move the selected thread lever into association with a selected one of the needles.

Abstract: The present invention is directed to a skipped-stitch mechanism on a sewing machine having a needle bar oscillating in a longitudinal direction, a control device for producing lateral swing-out motions of the needle bar in order to make different zigzag stitches, and a coupling device coacting with the needle bar and operated by a second control device so as to intermittently separate the needle bar from its driving member under the control of a program device in order to skip the stitching.

Abstract: A sewing machine and method of operating same in which the vertically reciprocatable needle bar is mounted in a guide capable of swinging movement back and forth and the guide, in addition, is shiftable by a separate drive upon withdrawal of the needle from the fabric to form locking or anchoring stitching at the end of a stitched seam.

Abstract: A linear motor is used to jog the needle bar and gate beyond the normal jogging range in order to disable a latch and separate the needle bar from the sewing machine driving means. The linear motor is driven into this abnormal excursion beyond the usual jogging motion by supplying a known needle position signal to the servoamplifier system for the linear motor and providing a separate voltage from a regulated voltage source which is summed with the specific signal in order to provide sufficient electromotive force for jogging the sewing needle beyond the normal jogging range.

Abstract: A sewing machine is provided which automatically drives an embroidery frame in two directions of X- and Y-axes during the time a sewing needle is disengaged from a cloth to be worked. An X-axis drive system and a Y-axis drive system are provided which drive the embroidery frame in the directions of the X- and Y-axes in a conventional manner. The machine includes an electromagnetic clutch mechanism which selectively engages or disengages a needle bar with or from a needle bar drive system in order to permit an increased stroke selectively for which the embroidery frame is driven for each stitch.

Abstract: A skip stitch sewing machine is provided with adjustable means engageable with a camming surface on a needle bar for deflecting the needle bar when it is caused to descend while in an extreme lateral skip stitch position, and for thereby preventing a needle affixed to the lower end of the needle bar from striking a presser foot or throat plate.

Abstract: An embroidery machine having a plurality of needle bars mounted parallel to each other for the working of different types and colors of threads, with automatic change of the needle bars driven at the time by a drive shaft. A plurality of needle bars are movably mounted adjacent each other in a common needle bar block which is displaceable transversely to the embroidery movement. A driver is fastened on each needle bar. A drive carriage is movably guided on a guide bar arranged parallel to the needle bars. A drive carriage which is driven from the drive shaft by means of a connecting rod and a crank can be coupled by means of a switch pawl with a contact piece which is also movably guided on the guide bar. The driver of each needle bar is provided with a roller which can be selectively inserted into a fork-shaped recess in the contact piece.

Abstract: A needle bar coupling in an embroidering machine which has a plurality of needle bars driven by separate cranks operated by a drive shaft, comprises a crank which is connected to the needle bar and to the drive shaft to move the needle bar upon rotation of the shaft. For this purpose a coupling or collar is engaged on the shaft and it carries the crank. A pawl is pivoted on the crank and it includes a tooth portion which engages in a groove of the coupling so that the coupling drives the crank when the shaft is rotated. In order to disengage the crank and the needle bar drive a contact member is provided adjacent the pawl which is shifted to engage the pawl and dislodge the tooth of the pawl from the coupling.

Abstract: An embroidering machine comprises a plurality of embroidering head each equipped with a plurality of needles formed into a group each with its thread. A needle bar is engageable with one needle at a time in the group to bring the needle from a rest position thereof into an operating position. A presser foot mechanism with a presser foot attached cyclically moves the presser foot upwardly and downwardly from an upper dead center position to a lower dead center position. The presser foot is provided with a hole for the passage of the one needle. Thread cutting and holding devices are provided for cutting the thread of the one needle to form a thread end portion and hold the thread end portion. Upon the termination of an embroidering operation with the one needle, the presser foot mechanism is operable to move the presser foot substantially transversely to a longitudinal axis of the needles and, after the thread is cut, to lift the presser foot upwardly beyond its upper dead center position.

Abstract: In a machine for embroidering a workpiece of the type having a needle magazine, a plurality of needles movably mounted to the needle magazine to define a needle groove, each needle of the needle group equipped with a different thread, and a mechanism for selectively imparting axial reciprocatory movement to the needles of the needle group to perform a thread change, an improved arrangement is disclosed in which the reciprocating mechanism includes a single elongated needle bar associated with the group. The needle magazine is movable relative to the needle bar to selectively align each needle with the needle bar. A disengaging coupling permits a selected needle of the needle group to be coupled to the needle bar. A locking mechanism is provided for detachably locking each of the needles to the needle magazine.

Abstract: An improved device for operating a needle in a sewing machine having a needle supporting clamp that is guided for sliding movement in a vertical plane by a needle bar. The needle bar is pivotably mounted on and depends from a support member which causes it to automatically align itself and follow the effective path of travel of the needle supporting clamp. The support member is mounted on the machine frame and is eccentrically positionable which provides a means whereby it can be selectively located in a position whereat the needle bar depending therefrom will never be subjected to more than a minimum amount of resistance by the needle supporting clamp during the latter's sliding movement thereon.

Abstract: An apparatus for selectively changing the distance of needle travel in a sewing machine in which the needle is carried by a needle clamp and reciprocated by a crank driven control lever along a pathway defined by a fixed guide bar. One end of the control lever has a lever pivotably connected thereto and the opposite end of this lever is pivotably connected to an eccentrically mounted and selectively positionable pin that protrudes from the machine's housing. Each of the available positions of the pin provide a means for effecting a change in the distance a needle travels during seaming for the purpose of accommodating workpieces of different thicknesses.

Abstract: A device for the intermittent interruption of the embroidery needle movement on automatically controlled embroidery- or sewing- machines, particularly multiple head automation embroidery machines, with at least one needle bar, the latter being driven by means of a crank rod and a crank from a drive shaft. The crank rod is pivotally connected with a drive carriage. By means of a pawl the drive carriage can be connected with a driver which is fastened on the needle bar. The driver in its turn is able to be secured in an upper deadpoint position by means of a controllable holding pawl with the simultaneous separation or disconnection of the drive carriage.

Abstract: The stitch-forming instrumentalities of a sewing machine are subject to small mechanical operational errors due to play in the motion-transmitting connections. The invention overcomes this problem by providing two springs which are respectively connected to a transmission element coupled to a driven mechanism of the machine, and to a drive. The two springs counterbalance one another with respect to the drive.

Abstract: A zig-zag sewing machine is provided with a compensating link and slide which engage on curved surfaces extending in a circular arc that has its center in line with the link. The compensating link and slide are situated between a crank and needle bar and move relative to each other during zig-zag operations to modify the operating effect of the crank and cause a needle to be similarly positioned relative to a vertical axis hook for loop taking in alternate zig-zag positions of the needle bar.

Abstract: The invention provides a twin-needle sewing machine for stagger sewing, wherein a needle bar is angularly adjustable transversely to its longitudinal axis and is so guided as to be longitudinally displaceable in an angularly adjustable holder. Herewith, two needles may be placed in a plane extendable parallel to the obliquely extending edge of the material part to be sewn on. With the obliquely cut-up material part fed with the material part to be sewn on, at the start of the sewing, both needles will penetrate simultaneously into the material part to be sewn on. Even in the case of obliquely running-on or feeding material pieces, sewing can be effected in a locking manner.

Abstract: This invention concerns a machine for making a textile product comprising a needle carrier shaft, reciprocation means for reciprocating said shaft, yarn feeding means for feeding yarn to a needle carried by said shaft, and control means for ensuring that the needle carrier shaft can be stopped only at an end of its reciprocation.

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: The needle bar of a sewing machine is mounted in a spherical bearing which is located adjacent the lower end of a needle bar bracket. The bearing is pivoted as a gate in the frame of the machine and the bracket is pivoted as a pendulum at its upper end to fixed structure in the machine head for movement in mutually perpendicular directions.

Abstract: An automatic control means for overriding the manually operable fast/slow control switch of a sewing machine to assure slow speed operation while the machine is operating in skip stitch mode, such as while basting to facilitate positive latching and unlatching of the needle bar. The automatic control means cooperates with the needle bar lateral jogging mechanism of the sewing machine such that when the needle bar is jogged beyond a predetermined range of laterally jogged positions, wherein skip stitch mode is effected, the automatic control means will automatically impose slow speed operation independent of the setting of the fast/slow control switch as selected by the operator.

Abstract: The invention relates to sewing machines, wherein the needle is mounted on the needle bar with both a transverse offset and an angular offset with respect to the axis of the needle bar. It may be applied to sewing machines for both domestic and industrial use.

Abstract: A tufting machine which includes mechanism for adjusting the stroke of the needles which is operable from the exterior of the machine and such that the bottom dead center position of the needles remains at a constant level in all positions of adjustment.

Abstract: A molded plastic guide provided in the head end mounting plate of a sewing machine receives the plastic toe of a latch carrier that is secured to a needle bar, and guides vertical reciprocatory movements of the needle bar.

Abstract: A transmission mechanism in a driving means for the needle of sewing machines. A needle holder having a needle secured thereto and fitted on a needle guide rod so that it is vertically oscillated thereon is joined to an oscillatory arm oscillatable along the needle guide rod by slidably fitting a front end portion of the latter in a passage provided in an end portion of a horizontal shaft which is fitted in the needle holder so as to be rotated therein to some extent. The passage in the end portion of the horizontal shaft is made at right angles thereto. The horizntal shaft has a vertical passage the diameter of which is large enough to prevent the needle guide rod passed therethrough from being slided on the inner surface thereof. The needle holder has a sufficiently large slide surface with respect to the needle guide rod.

Abstract: An electronic sewing machine with pattern selecting means is provided with control circuitry operable to increase stitch lengths in the work feeding direction by a predetermined integral multiple in a selected pattern by providing for pattern data retention and the discontinuance of endwise needle reciprocation during work feed operations corresponding in number to the said predetermined integral multiple.