US2672834A

US2672834A - Zigzag sewing machine

Info

Publication number: US2672834A
Application number: US117133A
Authority: US
Inventors: Arthur N Hale
Original assignee: Singer Co
Current assignee: Singer Co
Priority date: 1949-09-22
Filing date: 1949-09-22
Publication date: 1954-03-23
Anticipated expiration: 1971-03-23

Description

March 23, 1954 A N, HALE vZIGZAG SEWING MACHINE 3 Sheets-Sheet l Filed Sept. 22, 1 949 N @DE @aug/wko@ agrzfh uw' N Jfle/ 35.115/

EL libc www New March 23, 1954 A. N HALE ZIGZAG SEWING MACHINE s sheets-sheet 2 Filed Sept. 22, 1949 March 23, 1954 A N. HALE ZIGZAG SEWING MACHINE 3 Sheets-Sheet 3 Filed Sept. 22, 1949 Patented Mar. 23, 195.4

UNITED STATES PATENT OFFICE ZIGZAG SEWING MACHINE ArthurN..Hal e, Stratford, Conn., assigner 4toI'he Singer Manufacturing Company, Elizabeth, NMI., a` corporation of New Jersey Application-September 22, 1949, Serial` No.` 117133 9v Claims. (CL. 1112-159.)-

This invention relates to sewing machines: and more particularly to zigzag sewing machines of the lock-stitch type.

It has for its primary `object to` provide improved mechanism for shifting the lower stitchforming devices transversely of the normal direction of feed in unisonwith the laterally vibrating upper stitch-forming devices, whereby zigzag stitches of exceptionallength can be produced expeditiously and at high speed.

Another object of .the present invention isv to provide an improved form of loop-taker support by which a plurality of` rotary loop-takers can be. rigidly maintained in proper position during the lateral shifting thereof tol accommodatey the lateral throw of the needles inthewformation of zigzag stitches.

Still another object of the invention is` to pro.

vide a loop-taker support capable of `beingshifted laterally of the normal` direction of feed ofthe Work without disturbing the timing of'the driving i gears and withoutV interrupting the driving relationship between they driven i shaft pin the looptaker support and the; driving shaft in the machine-bed.

Other features,l objects and advantages" of 4 the present invention will appear from` the` detailed description of anfillustrativeformlof the saine, which will now be givenlin conjunction with-:the accompanying drawings, in which:

Fig. 1 is a front elevationalviewI partlyy in section, of a lock-stitchsewingmachine embodying the present invention;

Fig. 2 is a bottomplan viewapartlyY in section, showing the general arrangement` of the components in the bed, together-with the details of the shaft-coupling used;`

Fig. 3 is an enlarged transverse vertical sectional view of the bed taken substantially` along the line 3-3 of Fig. 2;

Fig. 4 is an enlarged transverse `verticalsectional view of the bed takensubstantially` along the line 4 4, Fig-y 2.;

Fig.` 5 is an enlarged top plan view-of a portion `of. themachine-bed` with-1 thethroat-plate` and slide-plates removedtoshow-the arrangement of the loop-takers. relative tol the feed-dog;

Fig.f 6 is atransversevertical sectional view taken substantially along the line 6 6, Fig. l5, illustrating the.Y preferred `way zpf supporting. the hook-saddles;

Fig. 7 is a transverse vertical sectional view taken substantially alcngthe` lirici-f1. Fig.. 1, showing the adjustable eccentric` used for vibrating the needle-barfirame laterally `ofthe normal directionctfeed:

Fig. Sais-fa vertical sectional View ci thev lower portiomof thedetentyusedtolock the adjusting disk of the needlewvbrating eccentric against turning` when chaiigfingV the width of the zigzag stitching, the detent beingl shown in adjusting disk lockingv pQsition;

Fig. `9 is a bottom plan viewof;` the detent shown in Figs. `8. y

Referring nowto the drawings, the illustrative machine comprisesyajframe having a base or Work-support Ill, av verticaliv standard II, and an overhanging armI l2 -terminatinggin a head I3. Power is supplied 'G Qthe machine through a beltdriven pulley It fromwany. suitable source of power.. such asflanv electric transmitter. The pulley :I 4 is securedifto amain drive shaft I5 which is journaled in ksuitable `bearings provided within thel arm I2. The main shaft. I5,-at the head end ofthe machine, `has fast` on.` it a counterbalanced crank I6` `connected-by thegusual link I1 to an endwise reciprocatory fneedle-bar I8v carrying at its lower end one ormcre needles I9. The needlebar I8. is mountedricr-endyvise reciprocation in the spaced bearings 2li` and2lof a laterally vibratory needle-bar frame` 22 fulcrumed at its` upper end on apivot-stud 23. At its lower end, the needle-bar. frame 22 slotted, as4 at 24, through which slotextends, a studiZ-S secured in the machine-.head I3,.the purposeof the stud 25 being tofsteady theneedle-bar-frame 22 during the lateral `vibratory movement `thereof about its pivotstud23.

The meansfor imparting the vibratory movenient to; the needle-bar frame` 22 preferably comprises a pitman 26 connected at one end to the needle-bar frame-andai'. its other end shaped in the form of a strap. toembrace an adjustable eccentric 21 mounted on a rotary cross-shaft 28 journaled in the oppositeside walls of the machine-arm I2.. The cross-shaft 28 is driven from the arm-shaft I5, at, one-half the` speed of the arm-shaft, by the. gears 29 and 30 (Figs. 1 and 7). The.adiustableteccentric. 2'! may be of any well known type,` but I prefer that itY be similar to that forming thesubiect cti-the U. S. patent of W.

lMyers,.-No .2,l;28.031issued August-2li, 1938. For

`ity of theeccentric. Tolock the adjusting disk 31. ot the eccentricagant. turning, there is` provided a.` `spring.-retracted` datent` 32. (Fig. 7i) journaled ina shouldered .bushing 33` xed in the trontsidewall of the bracket-arm I2. I When the detent is depressed, its lower end is adapted to enter a notch 34 provided in the periphery of the adjusting disk 3I and thereby lock the same from turning with the remainder of the eccentric parts. To maintain the detent in depressed or adjusting disk locking position, the detent is preferably formed with a cross-bar 35 which is normally buried in a transverse slot 38 formed in the bottom of the bushing 33, but when the detent is depressed it is shifted out of the transverse slot, the detent then being turned so that the cross-bar 35 abuts against the bottom of the bushing 33, as shown in Figs. 8 and 9. With the detent thus locked in depressed or eccentric adjusting position, the two hands of the operator are freed to lock a loop-taker shifting eccentric later to be described and to turn the pulley I4 to eifect simultaneous adjustment of the lateral throw of the needles and loop-takers.

In the production of relatively wide zigzag stitching, it is necessary in the type of machine illustrated to shift the loop-takers laterally in unison with the laterally vibrating needles. In the present case a pair of loop-

takers

31 and 33, which cooperate with the needles I9 in the production of lock-stitches, are carried by a suitable common support mounted for lateral reciprocation in the bed l0. As will be observed in Figs. 2 and 6, the loop-

takers

31 and 38 are mounted on

vertical shafts

39 and 40 which are journaled for rotation in antifriction bearings provided in suitable loop-taker saddles 4I and 42. The two saddles 4I and 42 are adapted to be rmly clamped in selected spaced relation by

screws

43 and 44 on a tubular carrier 45 journaled for endwise reciprocation in

lugs

46 and 41 preferably cast integral with the bed Ill. At its inner end, the tubular carrier 45 has secured upon it, by screws 48, one end of a cross-arm 49 shaped at its other end to embrace the outer race 58 of a thrust ball-bearing I (Fig. 2). The outer race is secured in the cross-arm 49 between a shoulder 52 formed on the cross-arm and a retainer ring 53 secured by screws 54 to the face of the cross-arm. The inner race 55 of the ball-bearing is mounted on the outboard section 56 of a two-part rotary bed-shaft, which outboard section is journaled in bushings 51 and 58 fixed in

lugs

59 and 60 depending from the bed I0. The inner race 55 of the ball-bearing is confined on the outboard shaft-section 56 between a thrust-collar 6I and the hub 62 of a spurgear 63 which meshes with an internal gear 84 fixed on the inboard section 65 of the two-part rotary bed-shaft. The spur-gear 63 and the internal gear 64 comprise a coupling between the outboard and inboard sections of the bed-shaft by virtue of which coupling the outboard shaftsection 56 may be shifted endwise relative to the inboard shaft-section 65 in unison with the endwise movable hook-saddle carrier 45, without interrupting the driving relationship between the two shaft sections. The loop-

takers

31 and 33, rotatably journaled in the two hook saddles 4I and 42, are driven through the

gears

65, 61 and 68, 69 from the two-part bed-shaft which is connected by a belt to the arm-shaft I5. It will be understood that the looper-taker saddles 4I and 42 are rmly clamped at their front ends on the carrier 45 and, as will be observed in Figs. 2 and 5, the rear end of each of the saddles is extended to form a projection 1I, 12 disposed to rest upon the exposed ends of the elongated shaftbearing bushings 51 and 58, the bushings serving as stationary abutments which cooperate with the saddle projections 1I and 12 in'assisting the 4 clamps in retaining the saddles in their normal operative position.

From the foregoing, it will be understood that the tubular carrier 45 and the two loop-taker saddles 4I and 42 are shifted as a unit laterally of the line of seam formation and, that movable simultaneously with thecarrier and saddles is the outboard shaft-section 53 of the two-part bedshaft, the connection between the carrier 45 and the shaft-section 58 being effected by the crossarm 49. The ball-bearing 5| carried by the crossarm 49 provides for free rotation of the shaft-section 56 relative to the cross-arm, but functions primarily as a thrust bearing to displace the shaft-section 56 endwise in response to the sidewise movement of the cross-arm 49.

Means is provided for sidewise shifting the cross-arm 49, and this means is best shown in Figs. 2, 3 and 4. The cross-arm 49 is provided with an ear 13 apertured to receive a conical portion of a stud 14 threaded into the split end of a link 15 connected at its other end by a conical bodied stud 16 to one arm 11a of a bellcrank lever 11. To bind the studs 14 and 16 against accidental unthreading in the split ends of the link 15, there are provided the

drawscrews

18 and 19 which, when tightened, tend to pull the split ends of the link together in a manner to frictionally lock the studs 14 and 16 against turning. As shown in Fig. 3, the body portion of the bell-crank lever 11 is forked to straddle the inboard section 65 of the bed-shaft and provide upper and lower bearings into which extend alined pivot-pins 89 and 8| xed in the vertically spaced

lugs

82 and 83 of a supporting bracket 84 attached to the machine-bed ID preferably by screws 85. The other arm 11b of the bell-crank lever 11 is preferably formed cylindrical and slidingly enters a hole bored transversely of a bearing pin 86 freely journaled in a socket 81 formed in one end-portion of a pitman 88 embracing at its other end a loop-takershifting adjustable eccentric 89 similar in construction to eccentric 21 At its end remote from the eccentric 89, the pitman 88 is provided with spaced fingers 90 which slidingly engage the attened sides of a guide-pin 9| secured in the supporting bracket 84, whereby the pitman 88 is steadied during its actuation by the eccentric 89. The eccentric 89 is mounted on a countershaft 92 which derives its rotary motion through a belt 93 from the arm-shaft I5, the speed of the countershaft being one-half that of the armshaft. From the above description, it will be appreciated that rotation of the arm-shaft I5 will impart a rotary motion to the eccentric 89, which in turn will actuate the pitman 88, the endwise components of the pitman movement being utilized to oscillate the bell-crank lever 11 about its pivot-pins 8| and 82. Oscillation of the bellcrank lever 11 will impart endwise movements to the link 15 and thus shift the cross-arm 49 sidewise. As previously explained, the detent 32 is used for assisting in adjusting the eccentricity of the needle-vibrating eccentric 21. As shown in Fig. `1, there is provided a spring-retracted detent 94 which can be manually depressed to enter and lock against turning an adjusting disk 95 of the loop-taker shifting eccentric 89. When both of the

detents

32 and 94 are in depressed position the adjusting disks of the eccentrics 21 and 89 are locked and a manual turning of the pulley I4 will effect a simultaneous adjustment of the eccentricities of the eccentrics.

In effecting the production of zigzag stitching; it istnecessarythattherwork be'edvanced pastH the stitch-forming instrumentalities in proper *coordination with` thee lateraln` vibration ofisaid `instrurnentalfi-ties.` Im the-machine chosen toi-llustrate `the; invention,` the' wort:` is-advanced by` a `conventional, four-motion .feedingmechanism. This mechanism; best. shown:` in.` Fig.` 23,.. is actuated fromnthe; two-part .bed-:shaft 55,.4 65 `and comprises a. feed-advance adjustable eccentric'. 95 embraced by one;l end;` of. a-.pitman 9!r .connected `at its. other end. to the.A lower; end lof. a depending rock-armA twhich iszclampedon a feed-.advance rock-shaft 99 journaled in bearing.` bushings; |00, 1.0 Iy fixed thelbedl.` il);` Clampedtupon: the.r.ock. shaft 99. `is. an. upstanding feed-rocken` |02.,ha ving pivoted to itsupper extremity` a feedebar |103 forked at its rearendto straddle and.;engage `a feed-lift eccentric |04 mountedf. on; the; outboard section 56` of. the. rotary bed-shaft.,` Carried. by thefeed-bar |03 is a common form ofgfeed-dog |05. (Figs. 1 and 5) the teeth of which are adapted to project through the feed-dog., slots in..a throat-plate |06 mounted onA the bed:` |40.. Opposing the feed-dog isa presser-footfas.- tened` to the lower end of a `spring-depressed. presser-bar |08. It will be understood that the four-motion feeding mechanism will not be shifted. transversely of the seam line in` unison with the lower stitch-forming devices. Since, however, theoutboardshaft-section 56does move laterally as partY of' the lower stitch-forming unit, the feed-lift eccentric |04 ismade long so that it can shift endwise with the shaft-section 56' without becoming disengaged from. the forked end ofthe feed-bar |03.`

In the operation of the machina, the needles willbereciprocated once for each rotation of the arm-shaft I5 and also they will be vibratedt'ransversely of the line of feed inthe manner described 'to impart a laterali throw to the needles which, when coordinated with the four-motion feed, results in the' formation of vzigzag stitches. At the same time, through the. belt connections 93fwith the arm-shaftV |`5, the countershaft 92iis rotated and through the. eccentric 88', pitman 88; bell-crankA 11 and' linkldrives the looptaker saddle carrier 45 and' the outboardsection- 56 ofr the "bed-shaft, together with all the connected elements,V in unison with the vibrating needles. It will beappreciated that the crossarm connection 49. betweenthe carrier 45 and the outboard shaft-section 56 effectively ties these elements together sothat they movey asa singleiunit or assembly `inresponse toftherotationof the actuating eccentric. Theimechanism for. shifting this assembly-f is compactly` arrangedfinl the sewing machinev bed in `a manner such that the components thereof can be sturdily mounted while being readily accessible for assembly and repair. It will be seen in Figs. 2 and 6 that the loop-

taker supporting shafts

39 and 40 are journaled in vertically arranged antifriction bearings provided in the saddles 4| and 42, and that the

shafts

39 and 40 are located intermediate the carrier 45 and the outboard shaft section 56. 'I'he location of the loop-

taker supporting shafts

39 and 40 between the carrier 45 and the outboard shaft section 56 is advantageous from the viewpoint that it reduces by approximately half the small amount of turning movement of the carrier 45 about its longitudinal axis resulting from the play in the ball-bearing 5|. The intermediate position of the loop-taker supporting shafts therefore contributes to the rigidness of the lower stitch-forming mechanism.

fleeting ythus setz` forth 1ther -nature=-ot:ther-imvention, what I Aclaim. herein: is:

l. In a sewingtmaehinahaving arframee including a bed-and atreven-hanging.'bracket-arm, a rotary arm-shaft.` journaled. im said. braclretarm, anl endwise reciprocatoryzand. laterally vibratory needle carried by saidbracket arm,aa second shaft journaled said. lbrachet-arm-1.and actuated `by and disposed transversely ofwsaid' `armi-shaft,.` an adjustable eccentric mounted.. on-` said` second shaft, connections; actuated]` by said-eccentrici for vibratingA saidl needle; cubed-shaft.: journaleciy in saidl bed, a movableA loop-taker n'i'ountedfor` lateral vibration in said bed, operative connections with said4 bed-shaft forA impartinganeedle-thread loop-seizing` movements t'o-saidl; looptatalcex,` a counter-shaf t having a `longitudinal axisdisposed substantially .parallel to `the longitudinal` axis; of said` bed-shaft,l ansadjustable eccentrick mounted on said countershaft, meansfor actuating said countershaft,` andA connections-actuated said eccentric for` vibratingsaid` loop-taker inntimed relation with said.` laterallyj vibrating` needle;

2. In a sewing machineihaving a frame includ?- ing a. bedand anI oyerhanging: bracket-arm,n an endwise reciprocatory and` laterally` vibratory needle supported by said bracket-arm, a `two-paizt shaft journaled `in saidA bedsand? havinginboard and outboard sections coupled together.` for limited relative end-wise, movement,` a.: carrier slidably supported? in said bed',` aloop-taker mounted on said carrier andi: operatively.. connected to the outboard sectioiriofsaid two-part shaft, a cross-arm connection between said/icar- `rier and said outboard shaft-section forming with said carrier and said shaft-sectionca unitary assembly, a rotary.` shaft,l aneccentric mounted on said rotary shaft,1and1a.l`inlcpivoted at one endu to said cross-armand` at itsavoth'er end operatively connected` to said eccentricfwhereby when said shaft is rotated` said unitary'fassembly is vibrated in unisonwith said laterally vi; brating needle.

3. In a sewing machine` havingV aframefrincluding abed` and an` overhangingfbracket-amn, an endwise reciprocatory and` laterally vibratory needlev supported by said bracket-arm;attivo-part shaft journaled in saidbed1 andhavinginboand and outboard' sectionscoupled together'fon `limited* relativer endwise movement; at carrier slidably supported.` in said bed;.a.1oop-taker mounted fon saidI carrier and` operativelyfconnected:l torthe outboard section of said two-partshaft;.a1-.crossarm connection between said` carrienandlsa'id outboard` shaft-section formingswith said@ carrier and! Vsaid shaft-section.; a unitaryV assemblg;v a rotary shaft, aneccentriczrnounted on. szaide rotary shaft, a link pivoted at one end to said cross-arm, a bell-crank lever pivotally supported on said bed andl having one of its arms connected to said link, and a pitman connecting the other arm of said bell-crank lever to said eccentric.

4. In a sewing machine having a frame including a bed and an overhanging bracket-arm, an endwise reciprocatory and laterally vibratory needle supported by said bracket-arm, a, twopart shaft journaled in said bed and having inboard and outboard sections coupled together for limited relative endwise movement, a carrier slidably supported in said bed in substantial parallelism with the outboard section of said twopart shaft, a loop-taker mounted on said carrier and operatively driven by said outboard shaftsection, a cross-member clamped on said carrier and having said outboard shaft-section rotatably journaled therein but constrained against endwise movement thereto, a rotary shaft, and connections between said rotary shaft and said cross-member for moving said loop-taker laterally in unison with said laterally vibrating needle.

5. In a sewing machine having a frame including a bed and an overhanging bracket-arm, an endwise reciprocatory and laterally vibratory needle supported by said bracket-arm, a twopart shaft journaled in said bed and having inboard and outboard sections coupled together for limited relative endwise movement, a carrier slidably supported in said bed in substantial parallelism with the outboard section of said two-part shaft, a loop-taker mounted on said carrier and operatively driven by said outboard shaft-section, a cross-arm fixed on said carrier and carrying a ball-bearing in which is rotatably journaled said outboard shaft-section, means constraining said outboard shaft-section against endwise movement relative to said cross-arm, a rotary shaft journaled in said bed, and connections between said rotary shaft and said crossmember for moving said loop-taker laterally in unison with said laterally vibrating needle.

6. In a sewing machine having a frame including a bed and an overhanging bracket-arm, an endwise reciprocatory and laterally vibratory needle carried by said bracket-arm, a two-part shaft journaled in said bed and having alined inboard and outboard sections coupled together for limited relative endwise movement, a carrier slidably supported in said bed for movement in a direction parallel to the longitudinal axis of said two-part shaft, a loop-taker mounted on said carrier, gearing operatively connecting said loop-taker to said outboard shaft-section, a crossarm rigid with said carrier and carrying a bearing in 'which said outboard shaft-section is rotatably journaled, means for causing said outboard shaft-section to shift with said cross-arm, a rotary shaft journaled in said bed, a link connected at one end to said cross-arm, a bell-crank lever pivotally supported on said bed and having one of its arms connected to the other end of said link, an eccentric on said rotary shaft, and a pitman connecting the other arm of said bellcrank lever to said eccentric.

'7. In a sewing machine having a frame including a bed and an overhanging bracket-arm, l

an endwise reciprocatory and laterally vibratory needle supported by said bracket-arm, a two-part shaft journaled in said bed and having inboard and outboard sections coupled together for limited relative endwise movement, a, carrier slidably supported in said bed in spaced relation relative to said two-part shaft, a loop-taker,

a. loop-taker supporting shaft journaled in said carrier intermediate said carrier and two-part shaft, a cross-arm connection between said carrier and said outboard shaft section, and mechanism connected to said cross-arm and actuated to vibrate said loop-taker laterally in unison with the laterally vibrating needle.

8. In a sewing machine having a frame including a bed and an overhanging bracket-arm. an endwise reciprocatory and laterally vibratory needle supported by said bracket-arm, a twopart shaft journaled in said bed and having inboard and outboard sections coupled together for limited relative endwise movement. a carrier slidably supported in said bed in spaced relation relative to said two-part shaft, a, loop-taker, a loop-taker supporting shaft journaled in said carrier intermediate said carrier and two-part shaft, said loop-taker supporting shaft disposed so that its axis intersects the plane containing the longitudinal axes of said carrier and said outboard shaft section, a cross-arm connection between said carrier and said outboard shaft section, and mechanism connected to said crossarm and actuated to vibrate said loop-taker laterally in unison with the laterally vibrating needle. Y

9. In a sewing machine having a frame including a, bed and an overhanging bracket-arm, an endwise reciprocatory and laterally vibratory needle supported by said bracket-arm, a twopart shaft journaled horizontally in said bed and having inboard and 4outboard sections coupled together for limited relative endwise movement, a carrier disposed in spaced relation relative to said two-part shaft and slidably supported in said bed for movement parallel to the longitudinal axis of said two-part shaft, a looptaker, a loop-taker supporting shaft journaled in vertically disposed bearings provided in said carrier, a cross-arm connection between said carrier and outboard shaft section forming with said carrier and said shaft section a unitary assembly, and connections actuated to vibrate said assembly laterally in unison with the laterally vibrating needle.

ARTHUR N. HALE.

References Cited in the file of this patent.

UNITED STATES PATENTS Number Name Date 1,141,092 Parkes May 25, 1915 1,840,571 Eames 1 Jan. 12, 1932 2,207,141 Zonis July 9, 1940 2,396,169 Fredericks Mar. 5, 1946