US2391517A - Thread take-up for sewing machines - Google Patents

Description

Dec. 25, 1945. v E EL 2,391,517

THREAD TAKE-UP FOR SEWING MACHINES Filed April 9, 1942 5 Sheets-Sheet 1 IN VEN TOR. CHARLES E RUBEL BY I I a ATTORN Dec. 25, 1945. r c. FJRUBEL 2,391,517

THREAD TAKE-UP FOR SEWING MACHINES Filed April 9, 1942 5 Sheets-Sheet 2 i 22 E H H :1

' INVENTOR. CHARLES R RUBEL BY 7 22 I Dec. 25, 1945.

c. F. RUBEL THREAD TAKE-UP FOB SEWING MACHINES Filed April 9, 1942 5 Sheets-Sheet 3 INVENTOR CHARLES Efil/BEL Dec. 25,1945. c RUBEL Y 2,391,517

THREAD TAKE-UP FOR SEWING MACHINES Filed April 9, 1942 s Sheets-Sheet 4 Zak"? YIIIIIIIIIII IIIIIIIIIIIII 1 NT CHARLES E RUBEL Dec. 25, 1945. c. F. R'UBEL I 2,391,517

THREAD TAKE-UP FOR SEWING MACHINES Filed April 9, 1942 5 Sheets-Sheet 5 IHU IN VEN T OH.

CH/I/PLE 6' F: RUBEL Patented Dec. 25, 1945 Charles F. Rube], Chicago,-Ill., assignor to Union Special Machine Company, Chicago, 111., a corporation of Illinois Application April 9,1942, Serial No. 438,222 7 19 Claims.

This invention relates to devices for taking up and yielding the needle thread in a sewing machine at the appropriate timesin' each cycle to allow for proper stitch formation and to avoid excessive slack, likely to become entangled in the moving parts. It relates especially to the, provision of such devices on a lock stitch sewing machine, in the operation of which a relatively large take-up action is required.

. An object of the invention has been to provide a simple but effective take-up, for machines of the character mentioned, which involves continuously rotating parts, of relatively small radius,

operating at a uniform angular speed. Vibrations incident to the high speed operation of reciproeating, or otherwiseaccelerating and'decelerating devices are completely avoided; Moreover, the action of the devices is such that the take-up and yield of the thread,v is effected smoothly, without jerking or otherwise placing a heavy strainupon the thread, such as is likely to producebreakage atthe high speeds now commonly encountered in commercialoperations.

A feature of the invention-is the provision of a pair of rotary take-up members, arranged for j simple rotation at different angular speeds about a common axis; Thus, a very simple and cornpact construction is provided for carrying out the primary purpose of the invention. The arrangement is such, moreover, that the two rotary'takeup means, operating in different planes, are adapted at. times to combine their effect and at other times to produce a differential effect, in taking up and yielding the thread, so as to-meet with precision the requirements of the stitchforming devices.

' A further feature of the invention is the provision of a pair of rotary take-up members acting upon the thread at opposite sides of a fixed thread guide, one of'the members having a cam-like'c'on figuration, the periphery ofthe cam' engaging the thread to provide just the required takeup action constructionthe cam-like element is arranged. to

effect'two' takeiup actions upon the thread dur- A II is a view primarilyin end elevation but partly in vertical section along the line of stitching.

Figs. III, .IV, V and VI are a series of views, largely in end elevation but partly in section along the lineof stitching, disclosing the, improved take-up means in relation to the rotary hook at different stages in a cycle of operation.

Fig. VII is a longitudinal, vertical section through the improved take-up means, the operating connections therefonand associated .devices.

Fig. VIII is a detail view in vertical section along the line VIII-VIII of Fig. VILshowin'gthe driving connections for the take-up means. I

Fig. IX is a vertical section'along the line IXIX of Fig. VII. I I

Fig. X is a vertical section along the line XX of Fig. VII, and

Fig. XI is atop plan view of the take-up means and associated devices.

Referring now to the drawings, the invention has been illustrated in connection with a lock stitch sewing machine of the type more fully disclosed in the patent to Christensen and Rubel, No. 2,113,572, granted April 12, 1938. Reference may be hadtov said patent for a fuller description and showing of the stitch-forming and work-feeding devices and the operating means therefor. These will be but briefly described herein.

As illustrated; the machine may have a frame comprising a. vertical standard In extending upwardly from one end of a base portion H and having atits upper end a laterally extending, overhangingarm l 2. This arm carries, at itsfree end, a needle head We. A shaft l3, extending longitudinally of the. overhanging arm, projects outwardly through the rear wall of the standard 10 and is provided with a combined pulley and hand wheel I 4 throughwhich power is supplied at all positions of the members. In the preferred to the machine. Suitable gearing [5 serves to connect the shaft l3. with a parallel shaft l-B extending longitudinally of the base H.

At the free end of the shaft l3 there is mounted a head I! carrying a crank pin l8 connected, by a link I9, with a vertically reciprocable needle bar 20 having. a needle 2| suitably secured to its lower end. Adjacent the needle bar is provided the usual presser bar 22 carrying at its lower end a presser foot 23, arranged to engage the work and urge it yieldingly against the work supporting surface of the base ll'. Any suitable means,

1 such as a lever 24, may be provided for lifting the .presser bar against the action of a suitable spring (not shown). A thread guide 25, secured to the presser bar, is adapted to be lifted with the latter to accommodate different thicknesses of. the

work and also to provide a certain amount of slack in the needle thread whenever the presser foot is raised. v

Beneath the presser foot a feed dog 26 is provided, this being arranged to pass upwardly through suitable slots in a throat plate forming part of the work supporting surface. Appropriate connections are provided for imparting-1 a fourmotion operation to 1 the feed dog to"-advance* the work during the desired portion of each cycle of the machine. -For this purpose the feed dog is carried by a feed bar 21 pivotallymounted on a "rock member 28, the latter being adapted for oscillation by suitable connections (not-shown.)

from the shaft I6. A downwardly extending-arm'- 29 of the feed bar is connected with a link 30 whose upper end is mounted on and. operated:

by a crank pin 3| at the end of the shaft i 6. This provides for the desired up-and-downmovements of the feed dog.

K'rotar'y' hook 32; secured to the end of a horizontally disposed shaft. 33-, Within the. base I]; i'sarraneedto. cooper-f with the needle. 24 in the formation.- of: a ldc stitch in well known manner. Shaft 33 is' a'd'faptedfto. be rotatfeda't twice. the angular speedl offthfef shaft I 6' through a pinion 341 secured to the shaft 33'ar 1d agear gely, cut out; to redpcef its weight, andian inner disewli. There is; similarly; seeu entoitne oute endofthe sleeve' Wasewnd, or n ner;jro ytake-u 'memberu comprising a; pfa fioi disc lflhand dfih Thet'wo take-up members" are" spaced" axiallyfwith respect to eachother and are se aiateaityia statifon'ary plate 45" attached tr; cr ws: 45. to the in d; fac q'rthe needle head. In viewofithegearing her'e- 1. ofn'e' revolution for each reciprocation} of, the

hand fwill' be giv n twof reyo1utibnsjior: each one ofthe member" 43fan'6i h in'qe will. tie-operated at the same. frequency asthe rotary .hoo k;

Referring. now particularly to Fig: II; the

source (not shown)", is rs'tpas'sejd'througha series of openings'iirr a gf fde 4'g secnred'te th end face of. then e die'heiad, From'this it; is" passed ar -u e suitable thread tensionihg; means, 49,

thencecver a spring tensionedpheckwire snee ried by an adjustable plate 59g (in the manner disclosed n the pending application of Christenet al., Ser... No; 369,243, filedfDecember 9, 195m thence downwardly under. the guide 25, then upwardly, behind a plate. l secure'd at one end" tolthe face of the; needle head, np to the takeup meinbertll, around a cam-like plate 52 r ns. p r 1 a' d a e-111p.membeh etwee the two outer faice.discsfidariqflb; thenceoutwardl'y beyond the periphery of the face disc's bar, The takeeup nembermi on the other under a pin a projecting rearwardly from the plate 45 and adapted to be inserted in any one of a series of holes 45b therein, then around a roller 53 forming part of a stationary or fixed guide secured to the plate 45 and disposed intermediate the plane of the plate 52 and the plane of the orbital path of a pair of pins or rollers 54, thenc'e across a; pin 5311 at the inner end of the guide 53 to the take-up member l3, across the path of said pins or'rollers 54 forming a part thereof extending between the outer face discs 43a and 4311, then downwardly to a. stationary guide 55, thence through a guide 56 carried by the needle, bar,. then through the eye of the needleg and finally down through the work to form a lobpbeneath the work around a portion oithe. bobbin holder.

Assuming that'the parts, at the commencement of a; particular cycle, are in the positions indicated in Fig II, it, will be noted that theneedle is rising and is ne r the upper'liinitl oz its movemerit. The loop thrown out". by. the needleat thecommencement of its 11 Yard movement has been engagedby thebeak152h" of'th'e rotary hook and has been extended by; the hook tov substantially maximu'rhfsizef. It, extends alinost across the full diameter" of the bbbbin holder and has been passed over the bobbinthread' 51. At, this stage in the cycle. it will be, notejd'theLt, the two thread take-up me "here have; very, nearly their minimum effect up; the path of the thread', i. e. the course of the'threadfrom' the guide. 25t'othe guide 5511's substantially its minimum length.

During the initial. portion of the movement from; theFi'g. II, position toward that of Fig; III,

the cam-like element 52f of the member 4 4. will yield a slight additional' amount of threadias the flat side 5211f is carried; counterclockwise. and allojwsthecourse of the threaditof straighten out between'the guide 2fifarrd'the top of'th'e element 52. At the same time the curved portion 52b of the cam-like element begins to vtake up a slight portion of the thread y'iel' the flats'ide 5211 but the net result i's'to; supply enough extra threadte completejthe loop: around the bobbin holder." During this; initialimovementi froinithe Fig; IIjno iti'ongtherollersj54 of the outer'takeup member: 43 make littlelor no change in the course of the t'lnefadi' between the pin 53aiandthe g uideg55j Now, howeveraasj thepartsflshift further toward theIEig', III posit'ifor'i' the rotary ho'ok3wil1 have passed itsjm aximum'requirement of thread andlwill have begun tojrapidlyfyieldtheloop from around the bobbin holder. The thread so yielded is taken up by bothof the me berSillan'd M due to the action oil; the; re 54jan'dithe' curved portion 52b; of the; Cam -l element 52. This take '-up actiojrrc'ontinues' on the part of bOth I of the members int'otlie positionin which the 'imaximum radius port on 5 j'oftIfecam-like. ele- Inentis effective and. in; which the' forward. roller 54 of the outer take-up member is" continuing to forr'n a; more extended loop b etwe'en'the' stationary' guides 53f J At; this. point in the operation, the needle sjat: substantially thereupper limit of" its travel", nd? the. loop previously thrown about. the bobbin holder is. almost comlstely tak n up. In proceeding; to the Fig. v position the rollers}? of the outertake-upi memer n nu o. he r akerp. zctipn ta t al-rats ut tithei s me im am-like element 5'2'wi1l beyielding ajportionotthe thread demanded by the rollersjic; The difff erential action' between the two take 'up' members is just stitch forming means cooperating with said sufficient to draw up the remaining portion of the loop previously around the bobbin holder and to draw this loop relatively slowly but tightly against the under side-of the work. Inthe course of this action, the check wire 50 is" drawn downwardly, against the action of its sp'ring,to substantially the level-of the-under surface of the threadengaging portionof guide 25 and in so doingyields the last amount of thread required by the outer take-up memberwThis maximum take-up action occurs slightly before the Fig. V position is reached, just about as the forward roller;54 reaches, or is carried slightly beyond,

- the vertical plane through the axis of member 43. In passing from the Fig.-IV to the Fig. V position, the needle will descend, sliding its eye along 'the thread until the point of the, needle is but a small distance above the work. -At-the same time the rotary hook willhave commenced its idle rotation and the thread-engaging beak 32a will have traveled about 90 irom its uppermost position. V f In passing now from the Fig. V tothe Fig. VI position, the needle continues to descend, reaches its lowermost position, and-commences'its .up-

ward movement. The thread en'gaging beak 32a of the rotary hook has completed its idle rotation and is about to seize, orhas just seized, the new loop cast by the needle atthe commencement of its upward movement. During this period, between the Fig. V andthe Fig. VI position, the rollers 54 will have yielded the thread at a relatively rapid rate by a substantial shortening of the course between the fixed guides53 and 55. It will be noted incidentally, that this course, during the period in question,- carries the thread around a portion of the fixed guide 25, Some of the yielded thread will have been takenup' by the needle which will have carried the loop downwardly through the work into the path of the rotary hook. However, a substantial portion of the thread yielded by the rollers 54 will have beentakenup by the inner cam-flike take-up element 52. This'element, operating at twice the angular speed of the outer take-up member, will have attained substantially its maximum takeup action by the time the Fig. VI position is reached. r r

Now, in proceeding from the'Fig. VI position back to the Fig. II position, both of the take-up members will yield the thread at a relatively rapid rate and their combined action at this time is suflicient toprovide the threadfor the formation of the loop around the bobbin holder to the extent required in arriving at the Fig. II position.

In a preferred construction of the new take-up the maximum radial distance from the axis of the shaft 42 to the outermost portions of the cam 52 and of the rollers is not more than 1.5 inches, thus avoiding excessive centrifugal forces. The combined action of the two take-up means, when held within this dimension, is adequate for the purposes of the usual rotary hook.

While an illustrative form of the invention has been described in considerable detail, itwill be understood that various changes may be made in the construction, arrangement and inter-relation of the several parts without departing from the general principles and scope of the invention. The terms and expressions used herein have been used as terms of description and not of limitation. I Y

. What I claim is:

- 1. .Inasewing machine a reciprocating needle bar, a needle carried thereby, complementary needle andacting upon a thread carried thereby,

and take-up means-cooperating with. said thread 2. In a sewing machine a reciprocating needle bar, a needle .carried thereby, complementary stitch forming means cooperating with said needle and acting upon a thread carried thereby,

and take-up meanscooperating with said'thread in'timed relation with said needle bar and complementary stitch forming means, said take-up means comprising a plurality of coaxial, rotary members, said members acting upon said thread in different vertical planes, and means for operatingsaid members at difierent angular speeds.

3. In a sewing machine a reciprocatingneedle bar, a needle carried thereby, complementary stitch forming means cooperating with said needle and acting upon a thread carried thereby, and take-up means cooperating with said thread in timed relationwith said needle'bar and complementary stitch forming means, said take-up means comprising a plurality of coaxial, rotary members, each mounted for simple rotation, and means for operating said members at uniform but different angular speeds. i

4. Ina sewing machine a reciprocating needle bar, a needle carried thereby, complementary stitch forming means cooperating with said needle and acting upon a thread carried thereby, and take-up means cooperating with said thread in timed relation with said needle bar and complementary stitch forming means, said take-up means comprising a plurality of coaxial, rotary members arranged to move in spaced vertical planes, fixed position thread guiding means intermediate the planes of movement of said rotary members, and means for operating said members at difierent angular speeds.

5. In a sewing machine a reciprocatory needle bar, a needle carried thereby, complementary stitch forming means cooperating with said needle and acting upon a thread carried thereby, operating means for, driving said needle bar and said stitch forming means, a fixed thread guide, a pair'of coaxial, rotary take-up members arranged respectively to cooperate with said thread in advance of and after its engagement with said guide, and connections from said operating means for rotating said members at different angular speeds. V

-6. In a sewing machine a reciprocato-ry needle bar, a needle carried thereby, complementary stitch forming means cooperating with said needle and acting upon a thread carried thereby, operating means for driving said needle bar and said stitch forming means at different frequencies, a fixed thread guide, a pair of coaxial, rotary take -u'p' members arranged respectively to cobar, a needle carried thereby, complementary stitch forming means. cooperating with said needle and acting upon a thread carried thereby,

operating means for driving said needle bar and s'a-id stitch forming. means, a fixed position thread guide, a pair of coaxial, rotary take-up members arranged respectively to cooperate with said thread in. advance of and after its engagement with said guide, and connections from said operating means for rotating said members at different angular speeds, the outermost thread engaging portions of said members being at a distance of not more than 1.5 inches from the axis of rotation of said members.

8; In a sewing machine a reciprocatory needle bar, a needle carried thereby, complementary stitchi'ormin'g means cooperating witlr said needle and acting upon a thread carried thereby, operating means for driving said needle bar and said stitch formin means, a. fixed thread guide, a pair of coaxial, rotary take=up members arranged respectively to cooperate with said thread in advanceoi and after its engagement with said guide; and connections from said operating means for rotating saidmembers at different angular speeds, said members and connections being so constructed and arranged that the threadongaging portions of said members at times produce an additive eifect and at other times a differential effect upon said thread.

9. In a lockstitch-sewing machine a main drive shaft, a reciprocab-le needle operated by connections from said shaft, a rotary hook arranged to cooperate with said needle in stitch formation, connections from said shaft for rotating said hookat a speed of tworevolutions for eachreciprocation of said needle, and a pair of coaxial rotary take-up members driven by said shaft and arranged to cooperate with a thread carried by said needle, one of said members being rotated at the same speed as said rotary hook and the other member being rotated at half said speed.

10. In a lockstitch sewing machine a main drive shaft,- a reciprocable needle operated by connections from said shaft, a rotary hook arranged to cooperate with said needle in stitch formation, connections from said shaft for rotating said hook at aspeed of two revolutions for each reciprocation of said needle, and a pair of coaxial rotary take-up members driven by said shaft and arranged to cooperate with a thread carried by said needle, one ofsaid members having means only adjacent its periphery for engaging said thread and the other of said members having thread engaging surfaces adjacent its axis and adjacent its periphery, said members being rotated at uniform but different speeds.

11.- Ina lockstitch sewing machine amain tating said hook at a speed of two revolutions for each reciprocation of said needle, and a pair of coaxial rotary take-up members driven by said shaft and arranged to cooperate" with a thread carried by said needle, one ofsaid members having thread engaging surfaces only adjacent' its periphery and the other of Said-members having thread engaging surfaces at widely different distances from the axis thereof, said members being rotated atdifferent but uniform speeds.

1 2. In a loc'kstitch sewing machine a main drive shaft, a r'eciprocabl'e needle operated by connection from said shaft, a rotary. hook-arranged to. cooperate with saidnee-d le institch formation, connections from saidshaft-for rostant: ma

'tating said hookat a speed of two revolutions for each reciprocationof; said needle, and a pair or coaxial rotary take=upmembers driven by said shaft and. arranged to cooperate with a thread carried by said needle, one of said members havingth-read engaging surfiacesonly adfaces at a substantially uniform radial distance from the axis ofrotation of said member, the other of said members having an unbroken thread engaging surface t substantially contin-uously varying radius from the axis of rotation of." said member, means for rotating said members at different angular speeds, and thread guiding means constructed and arranged-to guide a thread into the paths of said members indirect'ions normal to the. axes thereof for constant manipulationof. the thread by said members.

14'. A thread. take-up for a sewing machine which comprises a pair of eoaxially arranged, rotary members. one of said. members: having its thread engaging surfaces. at substantially the same radial distance from the axis of rotation of" said member, the other ofsaid members haviiig thread engaging surfaces at continuously varying radial distances from the axis of rotanon thereof, and means for rotating said members at different angular. speeds.

I5. A' thread take-11p for a sewing machine \i'rhi'chv comprises a pair of c'oaxially arranged rotary members,- one of said members having its thread engaging surfaces at substantially the same radial distance from the axis of rotation of said member, the other of said members having a cam-like thread engaging element so shaped and arranged that substantially all portions' of its" periphery will engage the thread 7 during rotation ofsaid m'ember; means for rotatin sa d m mbers at uniform angular" speeds, and thread guiding. means constrocte'd and arrangedts guidea thread into the paths of said members for constant manipulation thereof by said: members. I

6; A- thread take up for a sewing machine whiclicompri'se's' a; pair of rotary members, one of said members having its',thread engaging" surf aees' at" substantially the same radial distance from meansof rotation of said member; the otheroi said membe s having a cam-like thread engaging element so-shaped and arranged that substantially all portions of its periphery Will engage the thread? during r'ot'at'iono'f said memti forr'otating said otherof said at multiple of the angular speed of of sax members; and thread guiding means. constructed and arranged to" guide a tnr'ead in'to the "pains of said members for conoiation thereof by said members, g means including a roiier for engaging saidtli rad betw'een its pointsof engagement by said't pair of members;

1 7.25 thread. take-up for a'- sewing machine which comprises a; plurality of coaxially arranged rotary take-ap members, one of said members having th r'ad engaging means at a predetermined radial distance from the axis of rotation of said member, the other of said members having a cam-like thread engaging element arranged to hold portions of the thread at continuously varying distances from the axis of rotation thereof, and means for rotating said members at uniform angular speeds.

18. A thread take-up for a sewing machine which comprises a pair of coaxially arranged rotary members, one of said members having its thread engaging surfaces at substantially the same radial distance from the axis of rotation of said member, the other of said members having a cam-like threadengaging element so shaped and arranged that substantially all portions of its periphery will engage the thread during rotation of said member, means for rotaing said members at uniform angular speeds, and thread guiding means constructed and arranged to guide a thread into the paths of said members for constant manipulation thereof by said members, said cam-like element being adapted to impart two take-up actions for each take-up action of said one of said members.

19. In a sewing machine a needle thread takeup comprising a rotatable cam-shaped take-up member of continuously varying radius from the axis of rotation of said member, a second take-up member adjacent one side of said first-named member and arranged to move in a circular orbit concentric with the axis of rotation of said firstnamed member, means for operating said takeup members, and thread guiding means for guiding a thread into successive engagement with said members for constant and concurrent manipulation by both of said members.

CHARLES F. RU'BEL.

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