US1230355A - Looper mechanism for sewing-machines. - Google Patents

Description

A 1. P. @L A. H. was. LOOPER IVIECHANISIVI FOR SEWING MACHINES.

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I y APPLICATIOII FILED AUG.28. I9I5- 1,230,355Q

4 SHEETS-SHEET 2.

I. P. I AfH. wils. Y LOOPER MECHANISM FOR SEWING MACHINES.

APPLICATION FILED AUG.28. H315-V 1,230,855. Patented June 19, 1917.

4 SHEETS-SHEET 3.

J'. P. & A. H. WEIS.

LooPER MECHANISM FOR sEwxNG MACHINES.`

APPLICATION FILED AUG.28, I9l5- I l Patented June 19, 1917.

A4 SHEETS-SHEET 4.

UNTTED sTATEs I PATENT OFFICE.

JOHN P. WEIS'AND ALBERT H. WEIS, OF NYACK, NEW YORK, ASSIGNORS T0 LUCIUS N. LITTAUER, F GLOVERSVILLE, NEW YORK.

LOOPER MECHANISM FOR SEWING-MACHINES.

wTo all lwhom t may concern.'

Be it known that we, JOHN P. Wars and ALBERT H. WEIS, citizens of the United States, residing at Nyack, in the county of Rockland and State of New York, have invented certain new and useful Improvements in Looper Mechanism for Sewing- Machines, of which the following is a speciiication.

This invention relates to sewing machines,

. and more particularly to the stitch-forming mechanismthereof for making parallel rows of chain stitching, wherein the needles and loopers may be placed close-to one another.

to provide a wide range. of needle gages for various.. classes. of work where multiplestitching is required. The present improvement, however, more particularly resides in an improved looper mechanism whereby the loopers may have a very short stroke, for

instance about a half-inch movement into and out'of the needle loop, and a very narrow lateral vibration or movement from one side t'o the other o f the needles. Heretofore in machines of this characte the looper movement is usually the same as the movement of the needle; that is to say,

distance so as to travel at the same speed. In other machines, where the -looper movement is less than that of the needles, a dwell is vgiven to the loopers at the front and rear of such movement to compensate for the greater movement of the needles, so that the needle when presenting its loop to the looper would be traveling at substantially the same speed as the looper. Consequently a jerky, irregular and unsteady movement isthe result, and wear, lost -motion and objectionable noise result. This is entirely overcome in the present improvement, by reason of the short steady movement given Ito the loopers and the needles. The loopersbeing very short and thin' at the loop engaging portion thereof enablesthem to pass intol and out of very small needle loops and so greatly assist. in the handling of threads and the forming of the stitches with a minimum of tension'on the threads.

Another advantage is that with this short movement of the loopers no thread take-up, nipper or measuring devices are necessary, the thread is not serfed through the eyes of Specification of Letters Patent.

the looper, and practically no tension is re-l Patented J une 19, 1917.

Application led August 28, 1915. Serial No. 47,743. I

quently a very tight and flat stitch can/.be l

drawn well into the work with very little tension on the needlethreads.

The short movement of the loopersalso permits the use of a Very rigid feeding ,mechanism, as the ,shank of the feed may be close to the needles and operate directly under the main pressure of the presser foot,

whereas in the machines where a long looperthrow is used a great overhang of the feed dogs is' necessary, which greatly interferes -with the proper feeding of the work.

In the drawings accompanying and forming a part of this specification, Figurey 1 is a front view illustrating the looper mechanism, the cloth and throat plates being partlyin section to clearly illustrate the juxtaposition of the parts; Fig. 2 is a top plan view illustrating the loopers with the top arm of the machine and the cloth plate removed 4to clearly show the parts underneath the same; Fig. 3v is a sectional view taken on line 3 3, Fig. 2, and looking in Athe direction of the arrow, Fig. 2; Fig. 4 is a detail viewv of the looper oscillating eccentric crank connection, partly 'in section, and taken in line 4 4, Fig. 2; Fig. 5 isa detail view illustrating the right angle gear drive of the crank shaft for vibrating the loopers laterally; Fig. 6 is. a diagrammatic view illustrating the path of travel of each looper; Fig. 7 is,a'perspective'view,illustrating the relative positions of the cloth plate and throat plates; Fig. 8 is a detail perspective view illustrating the throat plate with its toplplate removed; and Fig.

9 is a bottom view of the throat plate illustrating the peculiar construction of the needle holes and the thread engaging and looper thread strand retaining slots.

Similar characters of reference indicate corresponding parts in the different figures of the drawings. p

The base lplate or bed 1 of the machine carries the upright portion 2 of the overhanging arm 3, which carries the usual needle presser bar mechanism generally indicated by 4. The needle holder 5 is carriedv by the needle bar for operating theusual needles 6, shown in the present instance as two 1n number. The needle operating lever 7 is actuated bythe usual pitman connection 8 and wheel eccentric 9 carried by the main driving shaft 10. The cloth plate 11 is secured at one end to the upright part 2 of the overhanging arm 3, the other end being secured at 12 to the front bearing 13 in which the main shaft 10 operates. A web or guard 14 is carried by the front end of the cloth plate 11 to guard certain of the moving parts. The usual feeding mechanism may be employed, and this comprises an adjustable crank 15 carried on the main driving shaft 10 and a pitman connection 1G to operate a rocker frame 17 connected with the feed bar 18 to operate the feed dogs 19, see Figs. 2 and 3. A feed lift eccentric 20 gives the necessary rise and fall to the feed dogs, while the adjustable crank 15 gives the to-andfro movement to such feed dogs. A looper bracket 21 is secured to the bed of the machine and has an end bearing 22 for the looper shaft 23 and a similar bearing 24, see Fig. 1, located intermediate its length. This bracket 21V also has two bearings 25 and 26, see Fig. 2, wherein the looper vibrating crank shaft 27 is supported. A bevel gear 28 is secured to this crank shaft 27 and meshes with a similar bevel gear 29 carried on the main driving shaft 10 to transmit rotary motion to the crank shaft 27. This crank shaft 27 is provided with a crank 30 operating between thebearings 25 and 26 and has thereon a split block 31 which operates in a fork 32 carried by looper shaft 23, it being adjustably secured thereon 'by a screw 33, and this mechanism imparts lateral movement tothe loopers in the path illustrated. in Fig. 6. Secured to the main driving shaft 10 is an eccentric 34 rotating in a strap connection' 35 having its other end pivotally secured to a crank 37, and this crank is secured to the looper shaft 23 for rocking the loopers into and out of the needle'loops. The face or width of the eccentric 34 is slightly wider than the strap connection 35 so that as the strap connection is operated laterally by the crank 30 the strap connection will always have a full bearing on the eccentric. Looper carriers 38 are secured to the looper shaft 23 and carry loopers '39 having loop-engaging blades 40- with the usual thread eyes and grooves on one side thereof. The usual lpresser foot 41 is employed to cooperate with the feed 19 to carry the work past the stitching position.

In the operation of the machine the bevel gears 28 and 29 are so timed with relation to the eccentric 34 as toI cause the loopers to move forward toward the needles at an angle thereto, so that there is no possibility of the loops of needle thread twisting away from the looper as it advances forward. This movement has the added advantage of placing the strands of thread into a slot hereinafter described in the bottom of the assenso throat plate wherein the thread is held at one side of the needle holes while the needle iscoming down to enter between the thread and the looper in the forming of the double thread chain stitch. 1nl Fig. 3 the looper will be seen in its foremost position at the time the needle reaches its full height, and as the needle comes down the looper is moved backward and laterally and the strand of thread indicated by 43 is drawn into the groove or slot 42 and held or retained to one side. On certain classes of work it is desirable to use a right-hand looper, while in other cases a left-hand looper is more advantageously used. The change from one to the other merely necessitates a change of the loopers and a reversing of the timing of the crank 30 by Shifting the gears 28 and 29 to change the path of travel of the loopers as represented by Fig. 6, so that the lo'opers will come in and go out on the opposite sides of the needles, in which case the needles are also threaded from the opposite side.

The improved throat plate, and its clothsupporting plate, is described and claimed in the contemporaneously pending application of Albert H. Weis, Serial No. 41,024,

tiled July 21, 1915, and assigned to the same allel with the milled or recessed surface of 1 the cloth plate 11 to facilitate in lining up the needle holes in the throat plate with the needles. To accomplish this the holes in the plate may be enlarged as shown at 52 and the recess in the cloth plate 11 be slightly larger than the throat plate 50 to permit its adjustment. The bottom plate 50 is provided with the usual feed slots 53, which may beof any form to suit the character of feed used, and the character of feed is usually designed to suit the number of needles and the style of work for which the machine is to be used. For lap seam-felling work it is desirable to have the feed slots extend up 4 to and slightly in front of the needles, as at adjacent tothe needle opening in a projection 12 shown herein as V-shaped, which extends in the plane of the plate and does not project below the bottom surface of the plate. Heretofore pins, spreader bars, etc., have been lused for the purpose of spreading and thereby forming a loop, but we have found in practice that the pins or spreader bars become disarranged and the .threads are apt to hook over the same so as to snag and break' the thread. Moreover, the pins become worn, as there is but a very small portion of them which coacts with the threads, and when they are worn they do not perform their functions properly. This has been overcome by the present improvement,

as the grooves are of considerable length,

so that the thread is retained during the en'- ing to enter betweenit take-up device tire forward movement of the looper andthere is no possibility of the thread snagging, as there is no portion upon which the thread could catch or hook and there are no projections below the bottom of the throat plate for the looper to interfere with, and

consequently-the thread is .more accurately,

handledthereby. In the present improvement as above stated, the strand or thread of the looper is held or 'retained during a certain part of the movement ofthe looper and this results in holding or retaining one strand of the looper thread to the needle hole while the needleis descendand the looper body. In other words, the present strand retaining device does not act in any similar way to pins or projections extending below the throat plate, which necessarily spread the thread and form a loop and so require a of some kind to take up this extra thread loop where it is cast from the pins. In the present improvement, as here- .mbefore stated, at the top of page 3, no takeup device is necessary or required to take up 1 the looper thread for the reason that there is no loop formed by this retaining device. As the' loopermoves backward and laterally the thread is drawn from the retaining de^ vice in proportion to the movement'of the looper, so that therefore there is no excess amount of thread or a loop to be taken up.

In the' operation of the needles and the loopers, the loo er thread of each looper is carried forwar -as the looper enters vthe needle loop.- The loopers move sidewiseand as these movements take place' the' strand j of. each looper thread-extending from the forward eye of the looper to the previous stitch passes to the groove or s aw out 42 so as to be helld or retain to needle hole as the needle is take a loop of thread from' the looper.

Threaded holes 57 are provided in the Ybottom or main plate 58, which has similar holes 59 to receive screws. This removable and renewable be gro'oved, as to guide the Vwork-or'seams as the case` one side of one, side of the descending to' plate 50 for attaching the top.

top plate 58 has feed slots 60 corresponding with the feed slots 53 and 54 of the bottom plate and is also provided with needle slots or holes 61 corresponding with the needle holes 55 of the bottom plate. It is obvious that the front edge of .these top yplates may slotted or otherwise shaped so may be. The throat plate 50 has an extending portion 62 in front ofthe needles and is cut away, as-at 63,- at each side thereof and has extending ends64.l The removable slide plate 65, 'see Fig. 8, fits into the irregular v shaped opening formed in the front of the plate 50 indicated by the parts 64, 63 and 62. The slide plate rests o n the rabbeted part 63 of the cloth plate 11 and is provided with a plate spring, (not shown), on the underside thereof to rest against the bottom of the' -cloth plate and hold the slide plate 65 in position. This slide plate 65 may carry a folder or vother attachment. sometimes secured to the bottom for running a strip underneath the garment.- j The removal of this slide plate affords Vquick and easy access to the mechanism below thecloth late. p In the present improvement the looper `shaft 23 is shown located close'to the bed plate 1 of the machine and about one-quarter of an inch forward of the needle, that 1s to say, the axis of the looper shaft is aboutv one-quarter of an inch forward of the working vpath .of the needle, (see dotted lines a and b, Fig. 3) The distance from the looper shaft to the bottom ofthe throat plate is These are shown approximately two and one-halfv inches, so that the looper swings on that radiuswith the result that the looper on itsv forward movement operates very close to the bottom of the throat plate in front ofthe needle hole, so that it is notv necessaryl to" have any projecting fingers or pins below the bottom surface of-the throat plate to form ,i

a loop in the looper thread. In other words, this location of the looper in the manner de-I scribed is such that the looper will coperate with the groove or slot formed retaining device in the throat plate, does not extend below the bottom surface on even though it I' i such throat plate.- This permits the needle loop, to cast off from the looper blade on the v backward movement thereof as the looper is moving sidewise during such backwardv movement. This action of the looper upon the looperthread or strand is due to the movement of the looper sidewise or laterally away lfrom the retaining groove and the looper does not during .its forward movement cast a loop around any projecting pin or loop spreader which, when used, has been located forwardly of the needle hole to fom a distinct loop take up the loose thread of this loop.A In short, in the present improvement there s requiring a take-up devifceito no pin or projection below the throat plate which draws off the looper thread to form a loop. .The point of the looper tips up slightly to release the needle loop and permits the drawing up of a tighter stitch and also enables a stronger feed to be used.

The various details may be more or less changed without departing from the spirit or scopel ofthe present improvement.

'e claim as our invention:

1. The combination of feeding mechanism, a needle, a throat plate having a groove and thread retaining means carried by a wall of said groove for retaining the looper thread so as to permit the needle to pass between the looper thread and the bodyof the looper, a looper constructed and positioned to coperate with said retaining means, means for moving said looper into t-he needle loop in a line substantially parallel with the line of feed and for withdrawing the looper from the needle loop, `and means for giving the said looper a lateral movement.

2. The combination of feeding mechanism, a plurality of needles .arranged in a line substantially at right angles to the line of feed, a throat plate having grooves and thread retaining means carried by the walls of said grooves for retaining the looper threads of the loopers to permit each needle to pass between the looper thread and the body of the looper with which it coperates, a thread carrying looper cooperating with each needle and constructed and positioned to coperate with its retaining means, means for moving said loopers into and out of their respective needle loops, each looper moving into the needle loop in a direction opposed to the direction of feed and'in line substantially parallel with the line of' feed, and means for moving the loopers'laterally.

3. The combination of feeding mechanism, a needle, a looper, 1means for moving said looper back and forth in a plane substantially parallel with the line of feed, means for giving said looper a lateral movement during its back and forth movement, a throat plate and looper thread retaining means carried thereby above the bottom surface thereof and arranged in the path of the looper thread whereby the looper thread engaged by the retaining means is held in position to permit the entrance of the needle between said looper body and the looper thread, said looper constructed and positioned to coperate with said retaining means.

4. The combination of a needle, a looper, means for moving said looper in one direction in substantially a right line on one side of the needle path and substantially parallel with the line of feed and for moving said looper in substantially a right line on the other side of the needle path in the opposite direction and for giving said looper a lateral movement during its back and forth moveto permit the entrance'of the needle between said looper and said looperV thread.

5. The combination with a plurality of needles and loopers and meansl for operating the same, of a throat plate having a plurality of needle slots and adjacent thereto and above the bottom surface thereof loop retaining means, one foreach looper for engaging the threads carried by the loopers and positioning the same for the entrance of the needles between said threads and the bodies of the loopers, said loopers constructed and positioned to coperate with said thread retaining means.

6. The combination of feeding mechanism, a needle, a throat plate having a slot and looper thread retaining means above the bottom surface of the plate and arranged in the path of the looper thread whereby the looperthread in said slot is retained in position to permit the entrance ofthe needle between said looper body and the looper thread, a looper constructed and positioned to coperate with said retaining means, and means for moving the-looper back and forth and for giving it a lateral movement during such back and forth movement.

7. The combination of a throat plate, feeding mechanism, a needle, looper thread retaining means located within the throat plate and arranged in the path of the looper by said means is retained in position to permit the entrance of the needle between said looper body and the looper thread, a looper constructed and positioned to coperate with said retaining means, and means for moving the looper back and forth and giving it a lateral movement during such back and forth movement.

8. The combination of a throat plate, feeding mechanism, a needle, looper thread retaining means located entirely above the bottom of said throat plate and arranged in the path of the looper thread whereby the looper thread engaged bysaid means is retained in -thread whereby the looper thread engaged position to permit the entrance of the needle between said looper body and the looper thread, a looper constructed and positioned to coperate with said retaining means, and

means for moving the looper back and forth tending in a plane parallel with thel plane of the plate'and lying adjacent to the needle slots for engaging the threadscarried by the loopers and positioning the same for the entrance of the needles between said threads' and the bodies of the loopers, said loopers constructed and positioned to coperate .with said retaining means.

10. In a sewing machine the combination of a throat plate 4provided with a needle slot, a needle, a looper, means for operating the needle and looper, and looper thread retaining means located above the bottom of the throat plate for engaging the looper thread and positioning the same-for the entrance of the needle between said thread vand body of thelooper, said looperconstructed and positioned to coperate with the looper, thread retaining means located above the bottom of the throat plate.

of a throat plate providedwith a needle slot,

a needle, a looper, means for operating the needle and looper, and looper thread retain-- ing means located wholly within the throat plate and extending in a plane/parallel with the plane of the plate and lying adjacent to the needle slot for engaging the looper thread and positioning the same for the entrance of the same betweensaid thread and the body of the looper,`said looper constructed and positioned to coperate with the looper thread retaining means located in the throat plate. Y

12. In a sewing machine the combination of a throat plate having a needle slot, a needle, a looper,`means or operating said needle and looper, and looper thread retain` ing means forming al continuation of the needle slot for engaging the looper thread. and positioning the same for the entrance of the needle between said threadand bottom of the looper, saidlooper constructed and positioned to coperate with said looper thread retaining means.

13. In a sewing machine the combination ofone or more'needles, a two-part throat plate comprising a bottom plate and a renewablev top plate having one or more registering needle openings and onev or more looper thread retaining means located in the bottom plate for retaining a thread loop, one or more loopers constructed and positioned to operate with theflooper thread retaining means located in the bottom plate, and means for operating the needles and looper.

14. In a sewing machine the combination of one or more needles, a two-part throat plate comprising a bottom plate and a renewable top plate having one or more registering needle openings and vone or more looper thread retaining means located-in the bottom plate for retaining athread loop, one

or more loopers constructed and positioned to operate with the looper thread retalnlng kmeans located in the bottom plate,and means for operating the needles and looper, the

number of looper thread retaining means corresponding to the number of needles and;

loopers.

15. In a sewing machine the combination of a throat plate provided with one or more needle slotjand compr1si-ng a slot formed portion for receiving the'thread carried by each vlooper, and positioning the same forthe entrance of the needle between said thread and the body of the looper, each of said loopers constructed and positioned to coperate with .said looper thread retainingvmeans located in the throat plate. 11. In a sewing machine the combination v16. In a sewing machine having a throat plate provided with one or more needle slots, one or more needles, one or more loopers," eachl havin a movement in an unlnterrupted ell1pt1cal path, means for operating said needle and looper, and looper thread retaining means in the throat'plate adjacent to each needle slot. and comprising a slot formed portion for receiving the thread carried by each looper and positioning the same for the entrance of the needle between said thread and the body of the looper, each of said I loopers vconstructed 4and positioned to sitioned so as to coperate with (the said' y .thread retaining means notwithstanding it does not project below the bottom of the -throat 'plate andA means for operating the V i needle and th e looper. 18. In a sewing` machine havin a throat plate, the combination of a nee le, looper' thread retainingmeans so formed in the;

throat plate as not to project below the bot; tom thereof and includin ing in the plane of thep ate7 a looper con- `structed and positioned so a`s'to coperate a groove extend-- with.- the said thread retaining means not" withstandin it does not project below the bottom of t e throat plate, and means for operating the needle and the looper;

19. In a sewing machine having a throat `plate provided with a needle opening, the

combination of a needle, looper thread retaining means so formed in the -throat plate as not to project below the bottom thereof and comprising a groove extending inl the plane of the plate,I one-of the walls of said I l groove terminating adjacent to the needleopening in a projection, a looper constructed and positioned so as to coperate with said thread `retainernotwithstanding iut does not project `below the throat plate, and means for operating the needle and looper.

vthe needle and looper.

21. In a sewing machine having a throat plate provided with a needle hole, the combination of a needle, a looper, means for operating said needle and looper, and looper thread retaining 'means `so formed in the throat plate as not to projectlfbelow the bottom thereof, the axis ofthe Llooper being located forward of the path of movement .of

' the needle so that the looper on its forward movement operates close to the bottom of the throat plate in front of the needle hole to cooperate with the looper thread retaining means.

22. In' a sewing machine having a throat plate provided with a needle hole, the combination of a needle, a looper, means for operating said needle and looper, and looper thread retaining means so formed in the throat plate as not to project below the bottom thereof and comprising a groove extending in the plane of the plate, the axis of the looper being located forward of the path of movement or the needle so that the looper on its forward movement operates close to the bottom of the throat plate vin front of the needle hole to coperate with the looper, thread retaining means.

23. In a sewin plate provided with -a needle hole, the'com` bination of a needle, a looper, means for operating said needle andlooper, and looper thread retaining means so formed in the throat plate as not-to project below the bottom thereof and comprising a groove extending in the lplane of 'the plate and a projection extending from a wall of said groove, v`the axis of the looper being lo. cated forward of the path of movement of the needle so that the looper on its forward movement operates close to the bottom of the throat plate in front of the needlel hole to coperate with the looper thread retaining means.

24. In a sewing machine having a throat plate provided with a needle opening, the combination of a needle, a looper, means for operating the same, and looper thread re machine having a throat naacte taining means iso formed in the throat plate as not to project below the bottom thereof and comprising a groove extending in the plane of the plate, one of the walls of said .groove terminating adjacent to the needle opening in a substantially V-shaped projection, the axis of the looper being located forward of the path of movement of the needle so that the looper on its forward movement operates close to the bottom of the throat plate-in front of the needle hole to coperate with the looper thread retaining means.

25. In a sewing machine having a throat plate provided with a needle opening, the combination of a needle, a looper thread retaining means located in the throat plate to one side of the needle slot and comprising a slot opening into the needle slot, a looper 'constructed and positioned to cooperate with said thread retaining means, and means for operating the needle and looper. A

26. In a sewing machine the combination of one or more needles and loopers, means for actuating the same, a throat plate and looperthread retaining means carried by the throat plate above the bottom surface thereof for engaging the thread strand carried by each looper and positioning the same for the entrance of the needle between said thread and body of the looper, said looper having its axis so located that it will during its movement operate close to the bottom of the throat plate to coperate with said looper thread retaining means above,v the bottom of such plate.

27. In a sewing machine'the combination of one or more needles and loopers, means for actuating the same, a throat plate, and

looper thread retaining means carried by the throat'plate above the bottom surface vthereof for engaging the thread strand carried by the looper andpositioning the same for the entrance of the needle between `said [thread and body of the looper, said looper `having its axis located forwardly of the Vpath of movement ofthe needle, whereby during the forward movement of the looper it will operate close to' the bottom of the throat plate and coperate withr the looper thread retaining means abovethe bottom of such plate.

, 28, In a sewing machinehaving a throat plate provided with one or more needle openings, the combination of one or more needles and loopers, means for operating the needles and loopers, and looper thread retaining means including a slot carriedl by the throat plate and corresponding in lnumber with the nuinber of cooperating needles and loopers and each lying adjacent to a needle opening for engaging a looper thread and positioning the same for the entrance of a needle between the thread andl the bodj7 of the looper, each of said loopers 130 having its axis so located that the looper plate provided with one or more needle holes, the combination of one or more needles, one or more loopers located in position to operate close to the bottom of Asaid throat plate, means for actuating the needle and looper, and looper thread' retaining means carried by the throat plate and corresponding in number with the number of co` operating needles and loopers, each of said looper thread retaining means located in proximity to its needle hole and eifective to retain the looper thread to permit the passage of the needle between the thread and the looper-.but ineffective to form a loop in the looper thread.

Signed at Nyack, in the count;7 of Rockland and State of New York, thls 21st ,day

of August, 1915.

. v JOHN P. WEIS.

ALBERT WEES.

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