US2696794A - Sewing machine - Google Patents

Description

Dec. 14, 1954 l L, KlRsCH 2,696,794

SEWING MACHINE Filed Aug. 27, y1951 5 sheets-sheet 1 l C5. Z

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SEWING MACHINE Filed Aug. 27, 1951 5 sheets-sheet 5 IN VEN TOR.

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United States Patent SEWING MACHINE Louis Kirsch, New York, N. Y.

Application August 27, 1951, Serial No. 243,851

Claims. (Cl. 112-197) The present invention relates to a sewing machine and more particularly to the mechanism thereof by means of which a lock stitch is formed from a single thread, which thread is intertwined by the mechanism to form an integral knot which prevents the stitch from slipping or unraveling.

My co-pending application, Ser. No. 241,527 tiled concurrently herewith, is concerned with a series of such lock stitches formed from a single thread by means of which ymaterials are sewed together and to which application reference is made for a full understanding of the invention of which this application is the subject, the present application describing a sewing machine for forming the vlock stitch concerned therewith.

As pointed out in my copending application, heretofore lock stitches were made from at least two threads which were interlinked with each other to prevent them from unraveling or being pulled apart and the sewing machines for forming them therefore included bobbins or spools containing the second or lower thread.

The present invention therefore contemplates the provision of a sewing machine having mechanism so arranged and constructed that a knot is formed in each stitch integrally in the single thread forming the series of stitches and on one side of the materials thereby sewed together.

By means of the present invention, a lock stitch is formed in a single thread without the use of a second or lower thread thereby eliminating the additional equipment heretofore required, such as bobbins, spools of yarn, additional tension devices, etc., which were necessary where an additional yarn or yarns were used to lock the stitch.

By means of the sewing machine of my invention, the

y cost of a lock stitch sewing machine has been considerably reduced and since the additional yarns are eliminated, the time required to s et up the machine has been greatly f reduced.

Where machines have many or a great multitude of needles, since it eliminates the equal number of tension devices, bobbins. and spools of yarn, which would otherwise be required, the sewing machine of the present invention has particular application.

The resulting multi-needle sewing machine, embodying my invention. is therefore relatively low in weight, is not complex in design or construction and will require less set-up time even though a lock stitch is sewed thereby.

Further, in some multi-needle machines, the needles are positioned comparatively close together thereby precluding sewing by them of lock stitches such as heretofore used since there is not sulicient room in the machine for the required bobbins.

However, withV the present invention, even with a multineedle sewing machine in which needles are closely spaced together, a lock stitch may be, nevertheless, readily sewed since bobbins are now unnecessary.

It will be recognized further that color matching of the thread and that in the bobbins and the like is extremely diiicult and not always possible, the necessity of which color matching is not required with my invention.I

Heretofore, machines employing bobbins have been limited to the use of relatively light threads, whereas, since the sewing machine of the present invention requires no bobbin, it therefore may use a relatively heavy thread of any size which was not possible heretofore.

The sewing machine of the present invention in distinction to the bobbin machines heretofore used, which bobbins require relatively frequent replenishing, is comparatively cheaper to operate since less labor is required and the machine is not idle to replenish the bobbin.

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In bobbin machines, which are continuously operated but which in their operation must require replenishment of the bobbins, breaks in the stitch will therefore occur necessitating repair to the slipped or skipped stitches when the machine is stopped for the replacement or replenishment of a bobbin. With sewing machines here contemplated to form a single thread lock stitch, on the other hand, such repair to stitches is unnecessary and the iow of sewed work will be continuous.

These, other and further objects, advantages and uses of the present invention will be clear from the description wicg follows and the drawings appended thereto, in w ic Fig. 1 is a section through two textiles or fabrics sewed together by a series of lock stitches embodying my invznttin and formed by a sewing machine here contemp a e Fig. 2 is a diagrammatic section of the sewing mechanism by means of which the lock stitch contemplated by my invention may be sewed, the needle being positioned in t'he extreme upward position just prior to its downward reciprocatory movement and the other elements of the mechanism correspondingly positioned.

Fig. 3 is a similar view, the needle in its ultimate down position through the loop of a preceding stitch and the elements of the mechanism, correspondingly positioned.

Fig. 4 is a similar view of the elements of the sewing mechanism relatively positioned at a point in the sequence of sewing operations, for purposes of illustration only in the description which follows, shall be considered as the commencement of the sequence of the sewing operations.

Figs. 5, 6, 7, 8, 9, l0 and l1 are succeeding relative positions of the elements of the sewing mechanism in the sequence of operations.

Fig. 12 is a section on the line 12-12 of Fig. 4.

Fig. 13 is a section on the line 13-13 of Fig. 4.

Fig. 14 is a view on the line 14--14 of Fig. 4.

Fig. 15 is a detail of the reciprocating finger in the mechanism.

Fig. 16 is a perspective view of the rotating hook or loop forming member of the mechanism.

Referring now to the drawings, I have shown there only so much of the component parts of a sewing machine by means of which a lock stitch of the type contemplated in my said co-pending application may be formed, as is necessary for an understanding of my invention, the mechanical linkages and means whereby the periodic oscillating, reciprocating and rotary motions are derived being conventional and well known to those skilled in the art.

In Figs. 6, 7 and 8, the form assumed by the thread or yarn at that point in the sequence of sewing operations shown, is illustrated apart from the component parts of the mechanism forming it, so that a better understanding of the mechanism may be had.

Throughout the specification, clockwise and counter clockwise directions are those as viewed in Fig. 2 and the upper or highest and the under or lowest positions are respectively the top and bottom of Fig. 2.

The cycle of operations commences with the needle 10 in its uppermost position above the fabrics or textiles 12 and 14, as illustrated in Fig. 2.

The thread or yarn 16 from a spool thereof (not shown) is threaded through the eye 18 of the needle, which is reciprocated from the uppermost to the lowerinost position and return by the conventional sewing machine means (also not illustrated, since it forms no part of my invention).

For ease in more fully comprehending the sewing machine here contemplated, I have illustrated in Fig. l, the

llock stitch embodying my invention which may be obtained by the operation of the sewing mechanism of the present invention, though it will be understood that for a more detailed explanation, reference should be made to my said copending application.

Reference should be made now to Fig. l for a short description of my lock stitch in relation to the members of the sewing mechanism here contemplated.

The materials 12 and 14, after the needle 10 has pierced them, the stitch formed and the needle withdrawn `and returned to its original position, are moved on the usual stationary feed plate 19 of the machine by the feed dog of the feed mechanism, which mechanism a'lso isk conventional4 and need" not'be shown; a selected distance for a subsequent needle piercing and stitch forming operation.

For an illustration ofthe componenti parts forming the sewing mechanism-of!my'invention and their'relative positions at thev uppermostY and lowermost needle: positions,-reference is-made to Figs. 2 and 3.

Referring particularly to Fig. 2, mounted for rotation by the shaft 22, which as usual operates in-timedlrelation to the needle 10, I provide the hook or loop-forming member 24l (see particularly Fig. 16)", which-in operation with the other elementsof the mechanism formslthe'knot 36 (see particularly- Fig'. 1)'constituting`the friction=lock of my lock stitch.

Reference should now bemadeto Fig. l forA adescription of this lock stitch which is described in greater detailf in my said co-pending application and` which' may be sewedy by a mechanism, an example of which is the subject matter of the present invention.

The thread 16, by means of the needle 10, to form the first stitch generally indicated bythe` reference numeral 28, pierces the fabrics ortextiles-12 and 14 at the point of entry 30.

ln order'to-followthe description, each succeeding'part of the continuous single yarn Willbe given a reference numeral throughout the specification, though it is tobe understood that the reference numeral 16 will refer to the entire thread from which the lock stitch, according to my invention, is formed'.

The first part 32 v of my stitch on the undersideof the textiles or fabrics 12 and 14 passes through the loop 34 ofthe preceeding stitch and the coil 36 of the knot, generally indicated by the reference numeral 26.

From this point, it leaves the coil 36 to form the loop 38 ofthe first stitch 28; From the loop 38, the yarn or thread returns to form the coilz 36 from which the part 39 is drawn through the loop 34 of the preceding stitch and brought by the needle to the upper side of the fabrics or textiles 12` and 14 at the point of entry 30.

Movement of the fabric or textiles by the feed dog 20, brings them intoposition underneath the raisedneedle 10 so that it and the yarn 16 enters the fabrics at the point of entry passing through the'loop38of the first stitch 28 beneath the textiles or fabrics and the coil 42- of the knot in the succeeding stitch 44.

This sequence of operations isrepeated to form` the lock stitches of my invention, as-by means of the mechanism and its action, which I shall now describe in detail.

Referring now to Fig. 2 and all the following figures, thepresser foot46, which is` of the conventional type, is lowered against the fabrics or textiles to hold them against the feed plate with a yielding tension. It istobe understood of course that the operation of the feed dog and the presser foot is conventional and need'` not be. described in detail.

Commencing with the position shown inl Fig. 2, the needle 10 pierces the material andV carries the thread or yarnl 16' to theV underside thereof to form the first stitch 2'8, as illustrated in Fig. 1.

As illustrated4 in Fig. 2, the hook member 24 is in the position illustrated: at the commencement of the sewing operation, the oscillating yarn carrier 48 and the reciproeating finger also being illustrated in the corresponding positions.

The finger 50 is' operated by any suitable means such as commonly found in machines, in timed relation to the movement of needle 10 and shaft 22.

As previously pointed out, in Fig. 3, to which reference is nowv made, the needle 1f) has pierced theA textiles or fabrics 12 and 14 and is illustrated in its lowermost down position to commence the formation of my lock stitch.

The first part 32 of the yarn 16 has been drawn through the loop 34 of the preceding stitch 28L through which loop the needle 10 has passed and against which needle the loop is tensioned.

The hook member 24, which is illustrated in Figs. 12, 13 and 16 is provided with the hook elements 52 and 54 and as illustrated in Fig. 3 has been rotated into position to engage the yarn or thread 16 inthe succeeding sequential positions, which I shall described.

Commencement of movement of the oscillating yarn carrier 48 and reciprocation of the finger 50 for the purposes of forming the knot 2:6 and' stitch loop in cooperation with the member 24 in the manner which I shall' de- CII scribed has not occurred and these members remain in the"pcfsitions assumed by'tl'lemY and'illustrated in Fig. 2.

Yarn carrier 48 is oscillated by shaft 66 commonly found in machines, in timed relation to the movement of needle 10, shaft 22 and finger 50.

For purposes of orientation and illustration only, I shall now consider the stitch forming operation commencing upon movement ofthe elements of the sewing mechanism into the positionsillustrated in Fig. 4. The needle 10 has been retracted fromI the lowermost position illustratedin Fig. 3v into the position illustrated in Fig. 4 prior to its being withdrawn from beneath the textilestor fabricsy 12 and 14.

It is understood of course that the member 24 is being rotated concurrently Withthe upward movement of the needle 10 which brings the hook 52 into engagement with the yarn or thread carried by the eye 18 of the needle 10 to commence the formation of the knot 26 and the loop 38 For an understanding of; the description which follows, it should be` notedthatz the coil.36 of the knot 26 is held inits formation by thehook element 56 extending down from the reciprocating finger Si): andv the coil 38- of the stitch 2S formed by thehook element S8Jat the endof the oscillating yar-nV carrier. 48.

Referring now toV Fig. 5, the needle 10ismoving upwardly'justprior to passing through the textile or fabrics 12 and14 to a position above them, the locking knot and loop formation being made on. the underside thereof in the manner that shall be further described.

The member 24 continues its rotation as the needle moves upwardly and places` tension on` the yarn 16.

Referring-now to Figs. l2 and. 13, it will be noted that the member 24. along its periphery is widenedy from the hook elements 52 and 54 throughout the remainder of the member so that the loop formed by the hook 52 is made wider as the member 24lcontinuesits rotation.

At this position inthe sequence of operations the yarn I6 is. pulled solely by the hook 52, only a single loop having two sides as illustrated inA Fig. 5, is formed.

Beneath the hookelement 54 of the member 24, l provide the groove 60, which permits the hook 56 on the reciprocating finger'SliK to be wiped past', as the member 24 rotates, as indicated in- Fig. 13, the hook 56 and the member 24 are aligned' so that they may function in this manner.

Referring now to Fig. 6, the needle 10 continues to move upward and the member 24 cooperates with the hook 56 of the finger 50 to forma double loop, which at the lower part of Fig. 6 I indicate by the reference characters 62 and 64.

The reciprocating finger 50 has moved to the left, as viewed in Fig. 5, the hook 56 picking up one of the sides of the loop illustrated' in Fig. 5, whereby the double loop illustrated in Fig. 6 is formed.

In the position illustrated in Fig. 6, the hook element SS-of the oscillating yarn carrier 48', as it oscillates, moves in a counterelockwise direction between the double loop 62 and 64.

As the member 48 moves on its shaft 66 in a counterclockwise direction between this double loop, it commences to pass through the elongated curvilinear slot 68 in the member 24 (see Fig. l2) which has been rotating, as previously described, in a clockwise direction, on its shaft 22.

Referring now to Fig. 7, the yarn carrier 48 has moved down through the slot 68 along the flat wall 70 of the member 24, which hasy been rotating in the opposite or clockwise direction to the counterclockwise movement of the yarn carrier 48.

As will be seen from a consideration of Fig. l2, the member 24 is shaped so that the surface of the wall '70 is flat and the hook elements 52 and 54 are out of line. That is the hook element 54 extends` toward the front of Fig. 16 and the hook element 52 extends toward the rear of that figure.

Since the hook elements. 52 and 54 are out of line, the hook element 56 of the reciprocating finger 50 will not engage the loop formed by the hookv element 54.

However, because of the shape of the member 24, which is narrower at the extremities of the hook- elements 52 and 54 and widens out therefrom along the upper edge of the member 24, motion of the yarn carrier 48, in a countercloclcwise direction, carries the element 58 at the intermediate part, for convenience referred to by the carrier 48 and thereciprocating finger, assumes the form illustrated at the bottom of Fig. 7.

The next succeeding position of the elements and the form assumed by the yarn under their inliuence is illus- 'trated in Fig. 8, which is the same position assumed by the elements of the sewing mechanism illustrated in Fig. 2. The member 24 has continued its rotation in a clockwise direction but the yarn carrier 48 has now reversed its motion to that in a clockwise direction which now serves to form the loop 38 of the stitch 28.

The reciprocating nger 50 continues to move forward, that is to the left of Fig. 8, thereby holding the coil 36 of the knot 26.

As a result of the movement just described, the yarn or thread is slipped ofi the hook 52. Concurrent oscillation of the yarn carrier 48, in a clockwise direction, pulls the loop 38 through the slot 68 and the coil of the knot is formed by the hook 56 of the finger 50.

The loop 74 of the coil 36, for convenience shown in Fig. 8, is held by the hook element 54 of the rotating member 24 in the position illustrated in Fig. 8.

Referring now to Fig. 9, as the member 24 continues l its rotation, this loop 74 is cast off the hook element 54. The needleltl commences downward movement to again pierce the textiles of fabrics 12 and 14.

The hook 56 of the finger 50 continues movement to the left of the drawing, the purpose of which is to place tension on the coil 36 of the knot, continued clockwise movement of the yarn carrier 48 also placing tension on the loop 38 of the stitch.

Referring now to Fig. l0, the knot and the stitch loop have been formed and continued clockwise movement of the yarn carrier 48 casts off the loop 34 of the stitch.

The needle 10 is now being passed through the loop 34 to form a succeeding stitch and knot in the manner just described. The linger 50 is at its extreme position to the left of the ligure and continues to place tension on the coil 36 of the knot 26.

The take-up arm 76 (Fig. 2) which is conventional, also applies tension so that the loop 34 is held against the needle 10 and the coil of the knot is concurrently tightened. This operation further serves to cast olf the loop 34 from the yarn carrier 48.

As illustrated in Fig. ll, the linger 50 commences to move to its original position to the right of the figures thereby releasing the coil of the knot and the needle 10 continues its downward movement through the loop 34 which is tightened around it by the take-up arm 76.

The operations are repeated through the positions of the elements as illustrated consecutively in Figs. 3 to l1 and previously described.

lt will now be seen that I have described a sewing mechanism by means of which the lock stitch described and illustrated in `my co-pending application may be formed and which eliminates the use of a second thread and the required bobbins, spools of thread, tensioning devices, etc., heretofore required to form a lock stitch.

As various possible embodiments might be made to the above invention, and as various changes might be made to the embodiment set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be construed as illustrative and not in a limiting sense.

I claim:

a single thread and having a knot therein, means for reciprocating a needle, a needle reciprocated by said means,

a rotating member in the plane of movement of the needle and relative to which the needle reciprocates, means for rotating said member, a first hook and a second hook spaced therefrom on the periphery of said rotating member, the body of said member terminating at one side thereof in a narrower portion forming the first and second hooks and thicker there throughout from said first side to the other side thereof, an oscillating thread carrier adjacent to the rotary member and having a hook member, means for oscillating said last member, said rotating member having a slot positioned and adapted for receiving therein the hook member of the oscillating thread carrier upon sequential rotation of the member and oscillating of the thread carrier, a reciprocating finger above and adjacent to the rotating member and thread carrier having a hook element positioned for cooperation with the hooks of the rotary member, means for reciprocating said finger, and means operated by said machine for moving said first, second and third mentioned means in timed relation to each other and to the reciprocation of said needle.

2. For use in a sewing machine for forming a lock stitch from a single yarn, a movable loop forming member, said member having flat parallel sides extending down from the periphery of the member on the inside thereof, a first hook at the periphery and a second hook below the first hook and out of line with the first hook, said hooks forming narrower portions extending into thicker portions of the loop forming member.

3. The loop forming member of claim 2, said loop forming member having a slot extending therethrough from the periphery thereof, a movable thread carrier positioned to be received in said slot for forming a stitch loop, and means operated by said machine for operating said loop forming member and said thread carrier in timed relation to each other.

4. The loop forming member of claim 2, said loop forming member having a slot extending therethrough from the periphery thereof, a movable thread carrier positioned to be received in said slot for forming a stitch loop, a mov able finger positioned for movement relative to said hooks for Vforming the coil of the knot in the stitch, and means operated by said machine for operating said loop forming member, movable finger and said thread carrier in timed relation to each other.

5. For use in a machine employing a needle and thread, wherein the thread is to be formed into a loop; a rotary loop forming member comprising a body portion; a pair of hooks extending outwardly from said body portion, said hooks lying in the same plane and extending outwardly from said body portion in the direction of rotation thereof and spaced radially of the body portion, said body portion extending rearwardly from said hooks and adapted to deliect a loop in said thread in a plane perpendicular to the plane of rotation of said member, said body portion including means forming one of said hooks facilitating crossing strands of said loop. i

6. For use in a machine employing a needle and thread, wherein the thread is to be formed into a loop; a rotary loop forming member comprising a body portion; a pair of hooks extending outwardly from said body portion, said hooks lying in the same plane and being adapted to grasp thread upon axial rotation of said member; and said body portion extending rearwardly from said hooks and having an arcuate contour adapted to deflect a loop from said thread in a plane perpendicular to the plane of rotation of said member, said arcuate portion of said body member being circumferentially discontinuous and having a curvilinear slot open at one end to permit the release of said deiiected loop at a predetermined point in the revolution of said member.

7. For use in a machine employing a needle and thread, wherein the thread is to be formed into a loop; a rotary loop forming member comprising a body portion; a pair of hooks extending outwardly from said body portion, said hooks lying in the same plane and being adapted to grasp thread upon axial rotation of said member; and said body portion extending rearwardly from said hooks and having an arcuate contour adapted to detiect a loop from said thread in a plane perpendicular to the plane of rotation of said member, said arcuate portion of said body member being circumferentially discontinuous and having a curvilinear slot open at one end to permit the release of said deflected loop and deliver the coil of a knot at a predetermined point in the revolution of said member.

8. In a machine having a threaded reciprocating needle to form a single thread stitch above the fabric being sewn; mechanism for reciprocating a needle; a needle reciprocated by said mechanism and carrying the thread through the loop of the preceding stitch; first mentioned means below the needle movable into engagement with the thread carried by the needle to form a loop; second mentioned means adjacent to and laterally of the first mentioned means movable into engagement with the loop formed by the first mentioned means to form two loops one of which is twisted on itself by the joint action of said first and second means; and third mentioned means above and medially of the first and second means movable into engagement with one of the loops to draw said last loop through said twisted loop; and means operated by said machine for moving said rst, second and third mentioned means in timed relation to each other and the reciproca.- tion of said needle.

9. In a machine having a threaded needle and mechanism for reciprocating the sarne, in combination; a rotary shaft below said needle, a member constituting a loop former carried on the shaft to be rotated therewith by said mechanism in timed relation with the reciprocation of the needle, a rst hook and a second hook carried by the loop former in relatively closely spaced relation one with the other and lying in the same plane for movement in a circular path lying adjacent to the path of movement of the needle, said first hook being adapted upon rotation of the loop former to engage a thread carried by the eye of the needle during upward movement of the latter to commence the formation of a loop therein, said thread engaged by said first hook being placed under tension by the upward movement of the needle, said loop former having a wedge-shaped body portion adapted upon further rotation of said loop former to widen the thread loop as the loop former revolves, said body portion having a curvilinear slot therein, said loop former having a transverse groove adjacent to the second hook, a reciprocating meinber adjacent to the top of the loop former and driven by said mechanism in timed relation to the reciprocation of said needle and the rotation of said loop former, said reciprocating member having a hooked extremity adapted to wipe past` the loop former through said groove and engage the thread carried by the loop former on the first hook to form two loops the outer ends of which are engaged one by said first hook and the other by said second hook, a thread carrier and supporting means therefor driven by said mechanism for oscillating the carrier, said carrier having an extremity positioned and adapted upon oscillation toward the loop former to pass through one of said two loops and enter said curvilinear slot in said loop former during rotation of the latter, said extremity on said thread carrier being adapted to grasp one loop and draw it through the other loop, said loop former casting off said thread upon further rotation of said loop former.

10. In a machine having a threaded reciprocating needle to form a single stitch thread above the fabric being sewn; means for reciprocating said needle; a rotatable loop forming member positioned below and in the path of the needle to engage the thread carried thereby after passing through the fabric to form a loop; means for rotating said loop forming member; a reciprocating finger at one side of the needle path and movable transversely thereof, said finger engaging said loop to form two loops; means for reciprocating said finger; an oscillating thread carrier adjacent to and laterally of the loop forming member, said carrier engaging one loop to draw it through the other loop to form a sub loop; means for oscillating said carrier; and means operated by said machine for operating the aforesaid four means in timed relation to each other.

11. For use in a sewing machine for forming a lock stitch from a single thread; a movable loop forming member having a body portion, said body portion having at parallel sides extending down from the periphery of the member on the inside thereof; a hook at the periphery of said body and a second hook extending from said body below the rst hook, said hooks forming narrower portions extending into thicker portions of the body ofthe loop forming member, said body having a transverse groove extending thereacross behind said first hook.

l2. The sewing machine of claim 10, said loop forming member having a slot extending down through the periphery thereof, said thread carrier being positioned to be received in said slot upon sequential rotation of the loop forming member and oscillation of the thread carrier by means operated by said machine.

13. In a sewing machine having the usual reciprocating threaded needle and mechanism for driving the same, together with the usual stationary feed plate and movable feed dog for feeding fabrics horizontally across the feed plate, and the usual pressure foot to position said fabrics relative to said feed deg, in combination; a rotary shaft below said feed table operated by said machine in timed relation to the reciprocation of said needle; a member constituting a loop former carried by said shaft, a rst hook and a second hook in relatively closely spaced relation one with the other and lying in the same plane for rotary movement in a circular path lying adjacent to the path of movement of the needle, said first hook being adapted upon rotation of the loop former by said shaft to engage thread carried by the eye of the needle during the upward movement of the needle to commence the formation of a loop therein, said thread engaged by said hook being placed under tension by the upward movement of said needle, said loop former having a wedge shaped body portion adapted upon further rotation of said loop former to widen the thread loop as said loop former revolves, said body portron havmg a curvilinear slot, said loop former having a transverse groove adjacent to the second hook, a reciprocating member below said feed plate and adjacent to the top of the loop former and driven by said mechanism in timed relation to the reciprocation of said needle and rotation of said loop former, said reciprocating member havlng a hooked extremity adapted to pass through said transverse slot in said loop former as the loop former is rotated and engage the thread carried by said rst hook to form a double loop the outer ends of which are engaged one by said rst hook and the other by said second hook on the loop former, a thread carrier and supporting means therefor driven by said mechanism for oscillating said carrier, means for turning one of said loops on itself, said thread carrier having an extremity positioned and adapted upon oscillation in one direction to pass between said loops behind the thread coming from said needle and enter said curvllinear slot in said body portion of the loop former upon rotation of the latter, said extremity on the thread carrier being adapted to grasp said thread in the unturned loop and withdraw the same from said loop former to form a knot in said thread, and said loop former casting olf said thread when the said first and second hooks are below the horizontal plane of said shaft for driving the loop former.

14. A method of forming a stitch from a single thread carried by a needle; comprising passing a needle through the fabric so as to form a rst loop in the thread below the fabric being sewn thereby; holding the loop thus formed and withdrawing the needle; tying a knot in said loop; again passing the needle through the fabric and through the bight of said first loop to form a second loop; and drawing said knot toward and adjacent the bight of said irst loop to complete the stitch.

l5 A method of forming a stitch from a single thread carried by a needle; comprising passing the needle through the fabric so as to forrn a loop in the thread below the fabric being sewn thereby; holding the loop thus formed and withdrawing the needle; tying a knot in said loop; again passing the needle through the fabric and through the bight of the loop; drawing on said thread to tension the bight of said loop around the needle and to place said knot close to said needle to complete the stitch.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,048,672 Finch Dec. 31, 1912 1,238,979 Baker Sept. 4, 1917 1,652,946 Lautenshlager Dec. 13, 1927 1,657,989 Baker Jan. 23, 1928

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