Abstract: There is provided a sewing device comprising a needle and a looper, the sewing device including a rotation shaft that rotates the looper, and a set bolt that has a conical distal end and positions the looper in an axial direction relative to the rotation shaft from a radial direction of the rotation shaft, in which the looper includes a through screw hole into which the set bolt is screwed, the rotation shaft includes a groove recessed from a peripheral surface of the rotation shaft, and the groove includes an inclined surface that the distal end of the set bolt contacts. In one aspect, in the sewing device, a cross section of the groove viewed in a direction along an axis of the rotation shaft has a V shape. As a result, a relative position between the needle and the looper can be positioned with significantly high accuracy.

Abstract: The invention relates to a method by which stitch openings in the area of a seam in a plastic skin (10), in particular a PVC or TPU skin, are sealed, said PVC or TPU skin being provided for a foamed part. Foamed parts of this type are used especially as interior fitting parts, e.g. as a dashboard, in the field of automobile manufacturing. The invention further relates to a PVC or TPU skin comprising a seam of said type.

Abstract: A sewing machine capable of replacing a feed dog in accordance with a type of sewing, the sewing machine including a feed bar performing a horizontal motion and a vertical motion by interlocking with a feeding mechanism, a feed dog detachably mounted on the feed bar, and a control unit that identifies the feed dog mounted on the feed bar. In the sewing machine, the feed dog includes an identification member that corresponds to a type of the feed dog, the feed bar includes a sensor that detects the identification member and outputs an identification signal, and the control unit includes a feed dog identifying means that, based on the identification signal from the sensor member, identifies the type of the feed dog mounted on the feed bar.

Abstract: An overlock sewing machine including a main shaft rotated by a sewing machine motor; a vertically moving sewing needle and an overlooper and an underlooper respectively driven by the rotation of the main shaft; a single looper drive shaft forming overlock stitches in cooperation with the overlooper, the underlooper and the sewing needle and rotated by the rotation of the main shaft, shaft line thereof being arranged perpendicularly to the main shaft; and a swing generating member having first and second swing generating portions fixed to the looper drive shaft for swinging the overlooper and the underlooper respectively; a first and second swing link mechanisms, both of which extend perpendicularly to the looper drive shaft, swinging the overlooper and the underlooper by conveying the drive force generated by the first and second sewing generating portions.

Abstract: In a cover stitch sewing machine which forms double chain stitch seams, needle threads are pulled out from the needle thread tensioning devices, passing over a thread hanging point on a needle thread pulling-up spring and the needle thread take-up completes drawing-up of the needle threads after needle thread loops of the respective needles are seized by the looper. The sewing material is then fed one feed pitch as the needles are moved down and the needle thread take-up draws out the needle threads, while the needle threads are pulled up at the thread hanging point by the elasticity of the needle thread pulling-up spring, thus preventing slack in the needle threads below the needle thread eyes. The threads which are connected with the needle thread loops, are drawn up by the thread hanging point of the needle thread take-up against the resiliency of the needle thread pulling-up spring.

Abstract: An upper looper control mechanism for sewing machines includes a control member and an end member connected between an active shaft for driving the upper looper and a connection member which is connected with the upper looper. The control member has one end connected to the active shaft or the connection member, and the other end of the control member is connected to a fixed part of the sewing machine. The users operate the control member to transfer the power of the active shaft to the connection member or to disengage the power of the active shaft from the connection member, so as to activate the upper looper or to stop the upper looper.

Abstract: The invention provides a sewing machine which comprises needle 1 that moves up and down while sticking into a cloth W on a needle plate and a looper 2 that projects and withdraws under the needle plate so that the looper 2 projects to catch a needle thread 10 left under the needle plate in accordance with the rise of the needle 1 and draw out the thread in accordance with the feeding of the cloth W, and on the other hand, the needle 1 falls to catch the looper thread left under the needle plate upon the withdrawal of the looper 2, whereby multi-thread chain stitches or covering stitches are formed, wherein a retainer rod 30 is provided which projects and withdraws backward and forward within a plane roughly in parallel with the feed surface of the cloth W while interlocked with the rise and fall of the needle 1, and this retainer rod 30 catches the looper thread 20 at the projection side of the looper 2 ahead of the needle 1 when projecting rearward, and holds the caught looper thread 20 between the rod and n

Abstract: A mechanism for a sewing machine for use in forming stitches by use of a looper thread which is controlled by a looper. This mechanism is adapted so that the looper thread which is run from a thread-thru hole to a stitch forming station is prevented from skipping over a needle penetrating point when a looper is moved upon descending of a needle, whereby stitches are formed without any skip stitch.

Abstract: In a looper thread control device for a double chainstitch sewing machine, the sewing needles are lowered securely into a thread triangle, even under the conditions of low thread tension and high speed operation, and with an elastic looper thread, without rib formation or skipped stitches in the fabric. A looper thread support member 1 moves up and down in cooperation with sewing needles NL, NR near the left end of the looper L. The looper thread support member 1 enters into the triangle prior to the descent of the sewing needles, and seizes the looper thread LT. The looper thread support member 1 holds the looper thread until the eyelet LE on the looper moves to the right side of the looper thread support member 1, thereby pulling out the looper thread LT from the thread source, and then releases the looper thread.

Abstract: A sewing machine includes two rods rotatably and slidably supported in the sewing machine and two lower loopers secured on the rods. A spindle is coupled to the rods by an eccentric and coupling members for rotating the rods and the lower loopers. One of the lower loopers may be moved axially together with one rod to which a pawl is rotatably supported, The pawl may be selectively engaging with the other rod for allowing the pawl to selectively moving the other rod axially and for allowing the lower loopers to perform two double chain stitchings.

Abstract: A driving assembly includes a shaft pivotally supported in a sewing machine. A rod is movable up and down and includes a looper secured on top. A follower is secured to the shaft and includes a post. A block is slidably engaged on the post and includes a pivot axle pivotally coupled to the rod for moving the rod up and down. The block is adjusted along the rod for adjusting the distance between the pivot axle and the shaft and for adjusting a moving stroke of the looper. The rod and the looper are stopped when the pivot axle is moved to coincide with the shaft.

Abstract: In a device for forming ornamental stitch seams, which comprises two or more needles (3a, 3b) moving alternately backward and forward through a needle plate (2) and a looper (5) cyclically movable following an elliptical trajectory (t) under the needle plate (2), the needles (3a, 3b) describe inclined trajectories (y) to form, with the needle plate (2), an acute angle turned towards the sewing direction (A), for crossing the looper trajectory (t) at a "crossing area" that, relative to a vertical direction (v) passing by the point at which the needles (3a, 3b) get through the needle plate (2), is shifted in a direction opposite to the sewing direction (A).

Abstract: A looper drive mechanism for a sewing machine includes: two loopers; looper drive shafts for driving the loopers; a main shaft extending across one plane transverse to the looper drive shafts; and torque transmission units for transmitting rotation of the main shaft to the looper drive shafts. The transmission units include: two slant grooved cams fixed to the main shaft and having grooves each extending through a full circumference and slanting relative to the main shaft; U-shaped followers each having two rollers, each of the rollers being supported by the looper drive shaft and rotating about its own axis within the groove of the slant grooved cams; and connection pins for pivotally mounting the U-shaped followers on the looper drive shafts so that the U-shaped followers are not rotatable in a direction in parallel with a line connecting the two rollers with each other but rotatable in a direction perpendicular to the line connecting the two rollers with each other.

Abstract: A looper drive cam is formed of a cylindrical cam which is fixed to a main shaft so that its axis is inclined thereto at an angle of .theta.. A looper drive fork forming an U-shaped cam follower is attached to a looper drive shaft, and is engaged with the inclined cam. The fork is attached to the looper drive shaft with a degree of freedom which allows for deviation between axes of the main shaft and the looper drive shaft. As the main shaft rotates, a cam face of the inclined cam changes in a range of .+-..theta. in a plane containing the main shaft, so that the fork rotates to rotate the looper drive shaft. Owing to the freedom of degree of the fork thus attached, the motion is transmitted smoothly, and wear and rattling are prevented.

Abstract: A radially facing circumferential surface of a cam, in at least some planes which radiate from the cam axis, includes lines which are inclined relative to the cam axis. The inclinations of these lines vary from one axial plane to another, except in the dwell regions of the cam. A wobble member is supported for oscillating movement about a wobble axis. One or more cam followers on the wobble member engage the cam on opposite sides of a transverse reference plane which is substantially perpendicular to the cam axis. During operation of the mechanism, the cam turns about its axis, and the wobble member oscillates about its axis. The mechanism is used in a sewing machine to move a looper.

Abstract: An overlock sewing machine is provided with means for driving a lower looper according to a plurality of different oscillational movements independently of each other, a clutch mechanism for changing the aforementioned movements from one to the other mode, a back and forth drive mechanism for moving a lower looper back and forth, a mechanism for transmitting movement of the back and forth drive mechanism to a lower looper and releasing transmission of the movement therefrom, a lower looper oscillating means for oscillatively moving a lower looper, a mechanism for releasing oscillational movement of the upper looper therefrom, and a motion change-over device for interchanging operation between the clutch mechanism, the transmission and release means, and oscillational movement release means. The arrangement permits conversion of various stitch formations in a sewing machine to take place in a simple manner without requiring complicated adjustment.

Abstract: A looper throw-out device containing a latch for catching the release lever of the looper throw-out device when the release lever is left in the unlocked position. The latch is mounted on the inside portion of the sewing machine cover. If an operator fails to lock the release lever before sewing, the latch catches the unlocked release lever when the operator attempts to close the sewing machine cover.

Abstract: The driving mechanism comprises a driving arm (10) fastened to a drive shaft (9) operated with an oscillatory movement about its own axis. Pivoted to the free end of the driving arm (10) is a support arm (11) carrying an upper looper (4). The support arm is also fastened to an auxiliary arm (12) pivotally mounted to a bearing pin (13). The bearing pin is eccentrically fixed to an auxiliary pivot pin (15) housed in the machine bed (2), with possibility of rotation about an axis which is offset relative to the axis of the support pin. The auxiliary pin (15) can be selectively oriented about its own axis according to different angular positions for the purpose of modifying the position of the axis of the bearing pin (13) and, as a result, the path taken by the upper looper (4).

Abstract: A triple-thread stitch is intended for sewing webs of netting over their edges, wherein one thread (2) forms straight loops (3) and two other threads (4 and 6) form turned loops (5 and 7). In the method of producing this triple-thread stitch, performed in a machine wherein the loop-forming members are the sewing needle (8), looper needle (9) and looper hook (10), the thread (6) of the looper hook (10) is formed into a turned loop (7) which is moved about the needle (8) until the latter's thread (4) forms a turned loop (5), and driven through the straight loop (3) of the thread (2) of the looper needle (9). In the machine for sewing netting webs over their edges with a triple-thread chain stitch, the looper hook (10) is mounted for moving about the needle (8) at the side of the device (17) for advancing the webs, which provides for forming from the thread ( 4) of the needle (8) a turned loop (5) when the looper hook (10) moves the turned loop (7) intermediate the needle (8) and its thread (4).

Abstract: An overedge sewing machine is adapted to perform three thread overedge stitching (STITCH TYPES 504 and 505) under the cooperating action of one needle (6) and an upper looper (15) and a lower looper (31). In addition to swing movement in the direction crossing the fabric feed direction, reciprocating movement in the fabric feed direction is selectively applied to the lower looper, whereby the front end of the lower looper is revolved around the needle. If the lower looper is revolved around the needle with the upper looper out of action, this operation provides double chain stitching (STITCH TYPE 401). Further, if the lower looper is revolved around the needle with the upper looper in action, this operation provides three thread double chain overedge stitching (STITCH TYPE 601).

Abstract: A Cardan gear assembly wherein rotary input motion of the main shaft is converted to elliptical output at the Cardan gear output centerpoint. The Cardan gear output centerpoint is connected via a ball and a pin slideable therethrough to a support having a work performing instrumentality arranged at its distal end. During operation, the elliptical output motion of the Cardan gear output centerpoint is transmuted into three dimensional, elliptical like motion at the tip of the work performing instrumentality.

Abstract: A mechanism for seizing and holding a thread, particularly the looper thread, of a chainstitch sewing machine to insure needle penetration of the thread triangle thereby assuring enchaining of the needle thread with the looper thread. Such mechanism includes an oscillatable thread spreader which transversely moves across the looper's endwise path of travel. The spreader motion being in timed relation with the stitch forming instrumentalities such that its effectively travel extends between the looper eye and the reciprocal path of the needle arranged closest to the looper eye when the looper is at its extreme loop seizing position.

Abstract: A looper throw-out mechanism is provided for bodily moving the looper out of its normal operative position for servicing. The throw-out mechanism includes a looper drive shaft having the looper releasably connected thereto, an operator actuated mechanism for selectively disconnecting the looper from its drive shaft to enable free bodily movement of the looper to an inoperative position, and a locking mechanism to prevent undesirable disconnection of the looper from its drive shaft. When looper servicing is desired, the locking mechanism is released by the operator permitting the looper to be disconnected from its actuating shaft and turned to a service position removed from its operative position. Upon its return, the looper is automatically coupled to its drive shaft in an operative position.

Abstract: An apparatus for adjusting stitch length in a sewing machine by means of a selectively adjustable eccentric possessing a self-locking device. The apparatus includes a support collar fixed on the machine's main shaft with an eccentric support mounted on the support collar which is operatively connected to a connecting rod for actuating the machine's feed dog. The eccentric support includes a central opening within which the adjustable eccentric is operatively disposed and which forms an integral part of a support ring rotatably mounted on the machine's main shaft. A manually operable push button serves to hold the support ring stationary and to release the self-locking device. The machine includes the conventional hand wheel fixed on one end of the machine's main shaft and, while the pushbutton is held in a depressed condition, the self-locking device remains in a released state thus enabling the selective rotation of the machine's main shaft by the hand wheel.

Abstract: A Cardan gear assembly wherein rotary input of the main shaft is converted to elliptical output at the output centerpoint. A force transfer means connects the output centerpoint to a means supporting a work performing instrumentality. Thus during operation the work performing instrumentality is driven through an elliptical like curve.

Abstract: A looper control apparatus for sewing machines which are adapted to form seams of double chain stitches both in a forwardly and reverse direction of sewing. The apparatus includes first and second driving devices for effecting travel of the looper in an elliptical pathway while sewing in a forwardly direction. A disconnecting mechanism is effective upon a selection to sew in a reverse direction in deactivating the second driving device so that the looper is actuated only by the first driving device which causes it to travel in a rectilinear pathway on one side only of the machine's needle.

Abstract: A sewing machine for simultaneously performing hem stitch and blind stitch. The sewing machine comprises a first looper placed above one end of a hem of cloth to be stitched and along the hem reciprocated to cross with a blind needle which is passed through the cloth; and a second looper placed above the hem to be stitched and adapted to move along a loop-like track which resembles the outline of a saddle and syncronizes generally with the reciprocation of said first looper.

Abstract: An apparatus for controlling movement of a looper while forming zig-zag stitches in a sewing machine. The apparatus is provided with a first drive device for moving and maintaining the looper in alignment with the machine's needle and a second drive device for causing the looper to travel in planes which are parallel when moving to cooperate with the needle in each of its stitch forming positions.

Abstract: A chain stitch sewing machine with a looper having an eye adapted for carrying thread and cooperating with at least one reciprocating needle as the looper oscillates and rocks in its operative position. The looper is supported on a looper carrier including a shaft journaled in an eccentric bore of a bushing which in turn is journaled in the bed of the sewing machine. A looper throw-out means is provided for bodily moving the looper out of its operative position for threading. The throw-out means includes a bushing support block receiving the bushing and pivotably supports a swinging latch member. The latch member includes a locking member adapted to be received within a socket member on the bed to prevent undesirable rotation of the support block, and further includes a resilient latching finger for gripping the support block to retard pivoting of the latch member when the looper is in its operative position.

Abstract: A device for selectively displacing sewing machine hooks to a position whereat they are readily accessible to an operator for threading purposes. The device includes a lever member pivotably mounted on the shaft which supports the hooks and an arm in the form of a cylindrical seat fixed on the shaft which carries a spring biased pin that is continuously urged into driving engagement with the lever member to effect oscillating movement of the shaft. A manually operable member is provided for disengaging the pin from driving engagement with the lever which permits the shaft to be rotated to a position that places the hooks carried thereby in an accessible position.