US2664840A - Sewing machine thread control - Google Patents

Description

Jan. 5, 1954 M. JOSEPH 2,664,840

SEWING MACHINE THREAD CONTROL Filed May 10, 1949 |6 3 Sheets-Sheet 1 FIE-1.5

INVENTOR.

Jan. 5, 1954 M. JOSEPH 2,664,840

SEWING MACHINE THREAD CONTROL.

Filed May 10, 1949 3 Sheets$heet 2 E3 55 v i JNVENTOR. s4

Jan. 5, 1954 M. JOSEPH 2,

SEWING MACHINE THREAD CONTROL Filed May 10, 1.949

3 Sheets-Sheet 5 IN VEN TOR.

BY Mic 64a JSseph Patented Jan. 5, 1954 UNITED STATES PATENT OFFICE SEWING MACHINE THREAD CONTROL Michael Joseph, West Roxbury, Mass. Application May 10, 1949, Serial No. 92,290

8 Claims.

The present invention relates to a sewing machine and more particularly to a means for stopping the machine when the thread making the stitch is broken.

The present means should be distinguished from that in which an indicator, as for instance, a bell is sounded, to tell that the thread of the machine is broken so that the machine operator will stop the machine when the indication has been given.

While such a system is satisfactory in some cases, it nevertheless fails to accomplish the desired results in many other cases, particularly where the sewing machine is a high speed machine, where the machine may be operated automatically, or where it is particularly desirable to stop the machine very quickly and in a given position. It is of course obvious that if the sewing machine continues to operate with the thread broken, there will be either no stitch at all, in

which case the needle would continue to pierce,

the material and therefore make unnecessary holes, or the stitching will be imperfect due to the lack of one of the threads. In the present invention the machine is promptly stopped, in fact, it is stopped in such a position that the needle may be readily threaded. The means employed in the present invention are applicable to all types of sewing machines whether using a bobbin or a looper or any type of sewing machine in which a thread is fed in the operation of the machine. The means of the present invention are mechanical in character, positive and operate upon the breaking of a thread to actuate means which disengages a clutch on the driven shaft of the machine from the power source and shortly thereafter halts the rotation of the driven shaft in such a position that the reciprocating needle is at the top position away from the material. The needle in this position is ready to be threaded without turning the machine even a part of a turn.

The present invention is particularly useful in so-called power machines which operate so rapidly that even though the machine is being watched by the operator, he may not be able to stop it before a great number of false stitches have been made subsequent to the break in the thread. The mechanism of the present invention will not only operate to stop the sewing machine where the needle thread breaks, but the mechanism will also be actuated by any other break which releases the tension on the needle thread. Where the bobbin thread breaks, it invariably happensthat theneeclle thread becomes loose. In other types of sewing machines this also happens, so that the present invention is useful in stopping the operation of the sewing machine where any one of the threads in breaking, releases the tension of the thread with which the present mechanism is associated. While in the embodiment shown in the present invention the means for stopping the machine are shown in conjunction with the thread feed for the needle, it may similarly be used forthread otherwise supplied in the system and it may also be used for machines operating more than one needle in which case a break in any one of the threads may operate to stop the machine.

These advantages and other features of the present invention will be more readily appreciated and understood from the description in the specification forming a part of this application when taken in connection with the draw-- ings illustrating an embodiment of the same, in which- Figure 1 shows a view of the invention partly in perspective and part schematically as applied to a sewing machine.

Figure 2 is a detailed view of a detail looking down at the top of Figure 1.

Figure 3 is a view taken on the line 3-3 of Figure 2.

Figure 4 is a side elevation partly in section as viewed from the right of Figure 1.

Figure 5 is a view similar to Figure 4 but showing the mechanism in another position.

Figure 6 is a perspective fragmentary sectional exploded view of certain details of the invention.

Figure 7 is a perspective exploded view of some of the elements shown in Figure 6 as viewed from the left of Figure 6.

Figure 8 is a fragmentary detail of the front needle drive end of the machine shown in front elevation, and

Figure 9 is a more complete view of the detail shown in Figure 8 shown as a side elevation.

In the arrangement indicated in the drawings, the machine as a whole is indicated at I. The needle thread 2 for this machine may come from a spool not shown, to the adjustable disc tensioner 3, whence it passes over an arm 4 projecting from the pivoted lever 5 through an eyelet 6 through guides 'l and 8 on the needle post and through the eye of the needle 9.

In the present invention, two threads ar indicated. The second thread It passing through the tension member 3' over the arm 4', through the eye 6', and then similary threaded as the thread 2 to a second needle, not shown in the drawings. The levers 5 and 5 are similar in construction and operate independently in the same manner, as in fact the whole system, so that only one side of the thread control elements will here- 5 after be described. The lever 5 is pivotally j ournalled in a support I l and has at its other end, a weight l2, which normally unbalances the lever so that gr fll itypplls the weight l2,doyvnvvard and t- .fl lt ii vt aurra dz re e t. when thethread 2' holds the forward end of the lever down. When the thread breaks, the for ward end of the lever will fly up and strike the arm 13 which extends over the;'for.wardenact.

both levers and 5 so that when the forwardendof either lever rises, it will hit the arm 13. The arm I3 is adjustably attachedeirfftheslot i5; by means of the nut 14 at the side of the pive oted lever 15 which is pivoted at the'top of a post H in a slot in the post by means of the pin I8! The rear endof the lever lfi is attached-to a membe'r or post" l9 a'sindicatedmore clearly in.F!igures1,'2, and 3-.' The post'ra is provided with al slot 20 which is bridged. at the tbp by f a; pin 2l, while the rear e nd of th lever lfids' pro-I" vided' with a hook-like member 2 2 which may be. inserted in the slot beneath the pin 2 l,- thus permitting the member l9 -to rest-fairly freely in a hole 23 (see Figure 4), at the free end cf an L-shapedlever 24. The member 49' is formed with ashoulder 25 anda Centrally located-pin 2E5 engaging inthe hole 23--and-=projecting from the underside of the end-2 l of --'the lever 24. Normally thelever i6-is so balanced 'that the forward end-carrying'the arnliii-is inclined downwards. inpvvhieh position the pinZS-is' held in its highest position as viewed in' F'igure 4 When th'e' larm l3 has been hit-by the lever 5; it will fly upwards sending the pin'26 -downwards in a position to be engaged'by the projecting boss 53 of the rotating clutch member 29. (See Fig. 5!) V v These elements may best be described in conjunction with the additional showing of Figures T6-an'd -75 In Figure 6;a portion of the machine frame is indicated at 305 on the end face are two pro'jecti-ng; diametrically positioned pins 3| and 32. These pins may project from t he smooth innerface 33-o-f the machine frame which may also serve as a -bearing for the driven shaft which connects with the front of the machine for operating the"needle bar and other mechanism. Theshaftt l is; shown broken away in Fig uretfieand indicated in dotted position. Fitting over the shaft and in adjacent opposing po-' sition. to the surface 33- is a cam" and reset-operating member 35 The drive shaft extends through the member 35. The cam 35-has on the face adjacent the face 33 -two diametricallyopposite concavexecesses-36- and 3l-in-a position 60. opposite the position of the pins 3| and 32: 'When th .pins .3 l and -32 lie 'in -these concave recesses, the face 38-of the cam member comes substantially... flush; againstwthe surface 33.- However when the .membei 35 is turned a-slightangle about the .shaft .34,lthe .pins. 3 I. and .3 fi move out of.lthe ,concavesrecesses 36 .and 31 thu forcing the.,,member..3 5.;to .the right as viewed in Figure 6.v

Lyingin facecontact. with-the. side 39. ofthe member.35,.is the clutchmember-29a This clutch member 29 is provided onits-left face as seenin- Figure...7, iwithra ball-bearing ring 4 Lengaging in slight recesses; on the surface 39 of the member 35;; The clutch..ele1nent 29is also provided with ak'eylway .43:indvhichlissituated the key 44. :(see

Figures 4 and 5), which at all times locks the clutch to the shaft 34 so that the clutch is always locked to the driven shaft, but permitting a small longitudinal movement with respect to the shaft. The other surface 40 of the clutch is provided with a suitable friction material which may be similar to that used as a brake lining and this may be attached to the surface of the clutch by thesscrews 45? set deeply the mae i lingi rs m-re aim nd l centrically mounted on the shaft is a flywheel 46. This flywheel is provided with a collar 41 on its inner side which serves as a cover for the clutch memberoandialso-as a pulley for a belt which fits in theslight concave outer ring 48. The flywheel is mounted freely on the shaft 34 and drives the clutch. 219;; when; the friction surface 40 of the clutch engages the inner surface 49 of the flywheel adjacent to it. On the outer side of the flywheel 45 is a sleeve member 50 which maybe lockedin place ontheshaft 34- by-- a set screw :al The sleeve tit-maybe'providedwithagroove 52-toreceive a belt-for dr-iving afeed-mechanism such as a feed of material to the machine:- Sincethe flywheel 48" is the; driving member andthe clutch 23 the 1 driven element which connects with the driven shaft iifl at all times; therotatiorr of theshaft 3fl wi-ll -st9D;When the flywheeldi and-thec1utch- 29 disengage. The elements line'upon the shaft 34 in such a way that when the is -operating,--- the member-35has its-conca ve recessestt =an'd3'l out of engagement with-the pins 3 l and- 32s In-this pesitionthe-surface-49 of-the clutch i9awill .be held firmly-in -contact-with the surface 59.;oi the flywheel lfi: so; that--wherr-;theflywheel is driven, the. shaft 34 will rotate-with it:

It ishob vious that in orderte disengage theclutch-the member-35 mustbe rotated-from a-position -in-- which ;the pins 3 I and- 32 do no t -=engage the recesses-St and}? to one in which they -do. This is taken-care of by the operation of the level; 2 --throu gh-- the action of the pin 2 6 proj ecting through the hole --23; in-the end; 2 10f the lever 24;: The clutch -29 for this purpose carries a'projecting; boss 53,- Thelmember 53 asit rotates comes, in; contact-with-the end-=of-thepi-n 26 'if this is in a projecting position-due to the break of the thread andthe upwardmotion of the forward end-- of the lever-l The L.-shaped lever Ztis pivoted. at 52 'to a fixed member attached to the machine by-the screw 55; lhe lever 24' 'iS tI1SlQ1;1 e. tQ this fixed member by the spring 56.: In normal" Position e e 'e nv hu -'germof he Occurs, l v T e l t le amendreset 1381' 351111 a nward ms;t. @...==sseen.i J sere- This x mrlishe ibr the en a ement. ai r lieieq sr rqm. he.memberfifiu n ene in ns? )rs s slit .inthesidepftm lon l r: e g l r ri he mhm mh 51s.

e lhr he-sprin 59. 0am te-fiensioat apinji in the latching recess 58. The cammemher 35 mi es. resiiienshew ine isun lse ears se nstihe ..t? v pf.th rpi fi ti h his orc d: pr a seinst t e. l w-e f d eg t e t m. mange: .theh l eelsn in lfiascension-me? piston in the well fit The bistqn, 16 3.;isv con; gt s g 3 Qd .3 the. lbot omee d p that rin 9 1 h g uten. mtntfifil.whi hfi es 9n.- its external sur-face the boss 53', i normally ro tatedinthe direction of the arrow A (s,e e Figures 4 and '5), and in normal operating positiongthe pin-25 is-just a little below the endjzl of the L shaped le -ver-- sothat the projectionjfg 'on the clutch ZQ-wvillelear; the pin 26 "as it ro tates In-the tilted position of the cam plate 35,shown in Figure 4, the boss or projection 53 will also clear the inclined surface of the pin-Bil. In Figurethe rear end below the inner surface of the end,

21 of the L-shaped lever. This condition is shown in Figure 5. When therefore the pin 53 on the clutch comes in contact with the end of the pin 26, the L-shaped lever it will be turned about its pivot in a counterclockwise direction, disengaging the pin 5'! of the cam plate 35? from the L-shaped lever and permitting thereby the cam plate 35 to turn in a clockwise direction bringing the recesses 36 and 3? into engagement with the pins 3! and 32. This will relieve contact between the clutch face dd and the face as and permit the clutch 29 to move away from the face is of the flywheel, thereby disengaging the driven shaft 35 from the driving system. The pin 65 projecting from the cam plate 35 limits the clockwise movement of the cam plate 35 when it comes in contact with the outside of the L-shaped lever. The pin 53 continuing its rotation now comes in contact with the corner of the pin 69 since this moves upward as the cam plate takes a level position, and brings the clutch to rest in the position shown in Figure 5. This position corresponds to the position shown for the needle bar in Figure 9 which is in its highest spot of its reciprocating cycle.

The arrangement indicated in Figures 8 and 9 is a usual arrangement used in sewing machines. The shaft {is drives the eccentric cam 61, which in turn drives the crank 68 to which the needle bar $9 is attached.

When the thread is broken, the machine should be threaded in the usual manner. In order to hold the lever it down until this is accomplished, the bar ii may be turned until it lies over the forward end of the lever it. The bar may be tightened in this position by the thumbnut it. After the machine has'been threadedthe bar i! may be moved away from the lever is and then the handle iii of the cam plate should be moved downward which will engage the clutch with the driving surface of the flywheel and thereby restart the machine.

It will of course be noted that moving the handle it downward will release the pin 6!] from the projection 53 and the pin 26 will normally be raised when the bar it falls to its normal downward position. The driven shaft 34 as has been previously stated, is capped by the sleeve member 5b, which holds the flywheel in position so that the surface is of the clutch may be pressed against the surface it of the flywheel for providing the driving coupling.

It should also be noted in the arrangement in the present invention that the thread tensioning members 3 and 3 are placed between the feed spool and the needle so that the thread will always be under tension during its feeding to the needle.

Having now described my invention, I claim:

1. In a device for stopping the operation of a sewing machine upon the breaking of a sewing thread of the machine, a driven shaft having a clutch plate keyed for a small longitudinal motion with respect thereto, a normally free running driving pulley concentrically mounted on the driven'shaft and having a surface in opposed position to said clutch plate, an operating cam plate concentric with said driven shaft and manually positioned for engaging said clutch plate with said opposed surface of said pulley, latch means retaining said cam plate under spring tension in said manually placed position, means operated by the breaking of the thread for releasing said cam plate and permitting said clutch to move axially on said driven shaft out of engagement with the opposed surface of said pulley, and means positioned upon the motion of the cam plate to engage said clutch for stopping the rotation of the driven shaft.

2. In a device for stopping the operation of a sewing machine upon the breaking of a sewing thread of the machine, a driven shaft having a clutch plate keyed for a small longitudinal motion with respect thereto, a driving plate having a friction surface concentrically positioned on said shaft in opposed position with respect to said clutch plate, a cam plate also concentrically position on said shaft on the other side of said clutch plate from that of the driving plate, means associated with said. cam plate comprising a pair of fixed pins and a pair of recesses on one face of the cam plate adapted to engage in said fixed pins in one angular position of said plate and in a second angular position to be longitudinally moved along the driven shaft, said cam in the second position moving said clutch plate and the friction surface of said driving plate into engagement with each other and. means actuated upon the breaking of the thread for permitting moving of said clutch plate from the second position to the first for disengaging thedriven shaft from the driving plate.

3. In a device for stopping the operation of a sewing tension machine upon th breaking of a sewing thread of the machine, a driven shaft having coaxially mounted therewith a clutch plate keyed for a small longitudinal motion with respect thereto, said clutch plate having a projection extending outward from the periphery thereof, a driving plate positioned in opposing position to said clutch plate, an operating cam plate coaxial with both said other plates, means associated with angular positions of the cam plate for holding in one position the clutch plate and driving plate in engagement with one another and in another position permitting their separation respectively, an inverted L-shaped spring tensioned lever pivoted at one end to the sewing machine for movement in a plane parallel to said cam plate and closely positioned thereto, a second lever having at a free end a pin extending through a hole at the unpivoted end of said first lever, said pin normally spaced in the same plane but clear of a projection on said clutch, a pin projecting from said cam latching into a recess in said L-shaped lever, means spring tensioning said cam with the pin in said latched position and means actuated upon the motion of said second lever for engaging said first mentioned pin with the projection on said clutch and moving said cam plate from the first position to the second, and means actuated thereby for engaging said projection for stopping said driven shaft.

4. A. device for stopping the operation of a sewing machine upon the breaking of a sewing thread of the machine which comprises a free running drive member associated with the machine, a thread feed mechanism having a lever fineness Tiihiiir witir one-- ngr in'fa raised position when chine mechanism including" sai'd thread feed mechanism and" said mechanism foryth'' reciprocating of the nedie and the feeding of the thread", said drive element and driven" member having a concentric axis; a clutch member mounted on'saiddriverlmember an'dkey'edthere to; means holding saidclutch member in engage ment with the 'free" ruhningdrive element; means operated when'said' end of; the lever lowered uponthe breaking of-the thread for releasing thev pressure holding said clutch member along said concentric axis in engagement with the free'running drive element,' ,said ciutch member having a: projection extending outward from; its periphery and a spring'pres'sed pawlmoyedin' position by said last mentionedmeansacting conjnngrtion with: said projection on saidclutch for stopping*said'drivenmemb er in a desired position;

5. In a device for stoppingythe operation qfa sewing; machine upon the breaking or asevving thread of the machine,- a driven shart'havin g a clutch plate keyed for aismall longitudinai Inqtion with respect thereto, a driving plate con; centrically positioned; with respect to said lutoh plate; a cam plate alsoconcentricallypositioned therewithimeans operative in; two ,angularly'dii; ferent'positions o'fsaid cam plate tor forcing said; driving and clutch-plates into engagementand for releasing-said force wherebysaid drivingnd clutch plates may gnoveout of engagementre; spectively; and means actuated upon the brealging or" the threadjior shifting saidmeans opera; tive' in two angula yl. i r nt ro iiiops. il e ii cam plate fron'r'the-first angular position to the second. t 1W V 6; In" 'a-device ion-stopping the operation: o 1 a win ma i e n n; breaki gi ewin thread of the machine;'a driven shajtpaving a clutch'pate keyedfor -a1 small longitudi al motion with 'respect thereto a driving rplate ooh; centrically positioned withre spect to *sai d-- cl ntch pi te; ayc m' a f lso. qpn e trie i y:eeeiii eei e i sme x p t e i .w I -le. l i f n n po ti ns q zi id emlele iq t i ie ie sale drivin and lutch pl e immers it-a e for releasing said force wherehysaid olutch' plates may move; out of I engag 1, ,.X i@.5 e: spectively;m s ctua eciun th gre sin 9i the thread for 'moving said means operativein two angi larly different positions of saidzcl'utch plat from the first angular position to the secoh'diand means automatically positioned with respect to the driven shaft upon the motion of the cam plate for stopping the motion of the drivenshaft in a'desired position.

'TJIn a device for stopping the operation of a sewing" machine upon the breaking of a sewing tensiohed' thread of the machine, a driven shaft having coaxia lly mounted therewith a clutch plate'keyed for a smail longitudinal motion with respect thereto, a driving plate positioned in opposing positions to said clutch plate,- an operating' cam plate'coaxial ,with both said other plates for moving said clutch plate longitudinally along said shaft for bringing it into engagement and out of engagement with said driving plate and means actuated when the tension on the thread is're1easedfor actuatingsaid cam plate including a; pivotedlever carrying a pin restrained by said tensioned thread; a spring tensioned lever having means'positionedfor restraining said cam plate to hold said clutch plate and drivingplate in engaging position through which last mentioned leversaid pin passes and meanspperated by the dropping of said pin when said first pivoted lever is' unrestrained for releasing said second lever and moving said canito a disengaging position of said clutch plate from saiddr iving plate,

8. In a device asset forth claim 7 including a' plurality of levers each held in restrained position by separate threads each under tension and means positioning sa id first mentioned lever to be actuated in any of sai'd plurality of I've'rs for untensioning oi anyoi said threads for stopping the operation of the sewing machine.

MICHAEL Jesse's.

references Cited "in the'fil of this patent UNITED STATES PATENTS Number Name Date 0, 556 cro s Apr. 8, 1884 gasses N b e Au 28, 1900 svasoa Parkes Dec. 31, 1907 1,192,821 oorraii July 25, 1916 1,361 56 are Dec. 7. 1920 1,411,19 homas Mar. 2 19 2 1499368 Mills a a1. July 1, 1924' 1;,5,QS,660 Leve'due Sept. 16, 1924 1,176,473 axton sept'zs, i930 1,791,322 Myers Feb. 3, 1931

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