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Publication numberUS2003461 A
Publication typeGrant
Publication dateJun 4, 1935
Filing dateSep 9, 1933
Priority dateSep 9, 1933
Publication numberUS 2003461 A, US 2003461A, US-A-2003461, US2003461 A, US2003461A
InventorsWalter Pearson
Original AssigneeWalter Pearson
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Sewing machine
US 2003461 A
Images(4)
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Description  (OCR text may contain errors)

June 1 w. PEARSON 2,003,461 SEWING MACHINE I Filed Sept. 9, 1933 4 Sheets-Sheet 1 Fig.1

June 4, 1935. y w, PEARSON 003,461 5 SEWING MACHINE Filed Sept. 9, 1955 4 Sheets-Sheet 2 June 4, 1935. w. PEARSON 2,003,461

SEWING MACHINE I Filed Sept. 9, 1933 4 Sheets-Sheet 3 Fig.6.

June 4, 1935. w, PEARSON -2,003,461

SEWING MACHINE Filed Sept. 9, 1933 4 Sheets-Sheet 4 Fig.8.

Patented June 4, 1935 r y I UNITED STATES PATENT OFFICE applicatiohlsleztliiinller 92:12:: No, 688,806

My invention relates to sewing machines, essecured to a rockshaft 20 Journaled in bearings peciallypMcKay sewing machines, and it has for provided on frame I. its object to improve the construction and opera- The, upper end of arm 19 is forked and ,emtion of sewing machines of this class. a braces both the lever II and fulcrum block l1 To this end I have provided an improved sew- The rear end portion of the lever is, also 6 ing machine of the class indicated having the forkedto provide a straight longitudinal slot 2| peculiar features of construction and mode of thatisoccup y a ri n m 22 fast on operation set forth in the following description, the main or prime power shaft 23 of the machine, the several novel features of the invention being and as said shaft and cam rotate in the direcseparately pointed out and defined in the claims tion of the arrow the latter vibrates lever I on 10 at the close thereof. the axis of fulcrum pintle I 8 and said lever, 'In the accompanying drawings: acts through pintle l5- and collar 12 to recipro- Figure l is a front elevation of the head of Cate needle-bar ll v i ymy improved sewingmachine. Owing to the triangular shape and design of Figure 2 is. a detail, partly in elevation and the cam 22 the lever I4 is caused to dwell mo- 15 partly in section, of the needle bar and cast-off. tionlessrfer a p d 0! timeet ch end its Figure 3 is a section on line 3-3 of Fig. 2. stroke, and consequently the needle-bar ll dwells Figure 4 is a section on line 4-4 of Fig. 1. correspondingly at each end of its stroke. Figure 5 is a detail, in plan, of the work guide n Fig. 8 thep a Shown in the p fl hereinafter referredto, I they occupy at the moment the needle-bar ar- 20 Flguref is asection on line 6-6 of Fig. 4. rives at the limit of its downward movementand Figure 7 i a front l tio of e ti of the needle-bar remains stationary in this lowerthe sewing mechanism showing the work in posimost pos io While. Shaft "I Sixty tion upon the horn or workrest of the machine. EreeS from the position shown- During t s 5 Figure 8 hows, in el v u ith need1e-bar dwell the whirl or looper (notshown) that is mechanism and part of thecast-ofl mechanism. Within the 0 ,1 y h -thr ad around Figure 9 shows, in" elevation, the presser-foot the needle 25 f needle-bar 'l l. mechanism and t ogjthepcasbofl h n m, Then, during the'next one hundred and twen- The illustrated embodiment, of my invention ty g es of movement Ofs the level comprises a head frame In which, as usual, is 15 swung on its fulcrum 9 l' th needle- 30 fixed'in position upon the upper end of acolumn her to e limit of its P dmQ m nt Where or post (not shown) having a base that is seated it dwells While shaft 13 rotates Sixty degree; upon, and usually secured to, thefioor. Frame mere- I I0 is a box-like structure having a horizontal top Thereafter, additional retehen of ha 23 to 35 wall, two oppositely disposed vertical side walls the extent er ehe hundred and twenty demes 35 and a horizontal bottom wall. Removably se- SW65 ap i ia ep s m s showninFls-e cured to the front of this frame is a closure plate with the heedle'her l at the hhht its d "a. Most of the operating parts of the ward movement. which completes the cycle of ing mechanism are housed within this frame Hi. t machine a a 40 The needle mechanism, comprises a needle The arcuate slot I8 of lever is concentric 40 bar H slidable vertically in bearings provided with the axls 9 rock Shaft "when e needle in the top and bottom walls of frame Ill. Fast cums lwermst at which on needle bar H s a collar '2 made at its time its needle 25 is within horn 24. Therefore, from; with an upstanding hper-turqd lug or ear it will be clear that the only effect of angular i 13 disposed between the aperturedarms of a :g the fulcrum arm ieto M 45 fork or yoke provided at the forward end of a g i fig fi i the e lever IL A pintle I5 pivotally connects the said u g n 8 Do needle arms to the mg or ear I y v w en enee ear occupies its lowermost posi- Intermediate its ends the lever II is made non whatever may be the .positmh er the crum arm I9. with a longitudinally disposed arcuate' slot 16, It is a feature of this invention that the Fig. 8, within whichis slidably mounted an cmm arm H) is auto 8 1 l apertured arcuate fulcrum block I! that is conangularly j t dve dg osiazrgd ig zl ig s ess nected by a fulcrum pintle It with a support foot mechanism, presently to be described, there- I9 herein shown as an angularly adJustable arm by to'vary the stroke of the needle-bar according to the thickness of the work as gauged or determined by the presser-foot mechanism in co-operation with the usual work-supporting horn 24, the stroke of the needle-bar being thus varied to regulate the length or size of the loop of each stitch so that said length or size is always appropriate to the thickness of the work through which said loop is drawn upwardly from horn 24 by the needle 25.

The presser-foot mechanism comprises a vertically disposed presser-bar 26,, Fig. 9, slidably mounted within ways provided upon the top and bottom walls of the frame Ill, the presser-bar being held within said ways by the front plate |0a whichis provided upon its rear side with blocks 21 bearing against the front side of the presser-bar.

At the lower end of the presser-bar is a presserfoot 28, Fig. 7; a work guide including 'a' roll 29 for engaging the edge of the sole that is being operated upon, and a feed tongue 30 provided at its lower end with a work-engaging feed point 3|.

Within the'box-like head In the presser-bar 26 is provided with a rigid rearwardly projecting arm 32, Fig. 9; formed with a slot 33 that is occupied by a pin 34 carried by one of the arms of a bell-crank lever 35 fast on the shaft 20 which carries fulcrum arm l9, Fig. 8. The other arm of bell-crank 35 extends upwardly. and is formed upon one side-thereof with an arcuate, groove or slot 36 within which is slidably fitted an arcuate clutch jaw or block 31. The groove or slot 36 is concentric with the axis of shaft 20 and its outermost and uppermost side wall 39 is also exteriorly arcuate andconcentric with the axis of shaft 23 and slidably mounted upon the exterior of this side wall 39 is another arcuate clutch jaw or block 40. V

The two clutch blocks 31 and 40 are disposed between the arms of a forked clutch lever 4| which embraces said two blocks and also the adjacent arm of bell crank 35. Clutch block 31 is formed at its middle with an aperture that is occupied by a pintle 42 by means of which said block is pivotally connected with the arms of lever 4|, the axis of said pintle being parallel with the axis of shaft 20. The clutch block 40 is likewise pivotally connected with the arms of lever 4| by means'of a pintle, 43 whose axis is also parallel with the axis of shaft 20.

The pintle 42 has connected with it one end of a coiled spring 44 whose opposite end'is fas tened at 45 to the frame III, the anchorage 45 being located so that the tension of said spring yieldingly urges the block 31 longitudinally in one direction with respect to the slotor groove 36.

The pintle 43 0f block 40 is connected by a link 46 with a stud bolt 41 fixed in position within an arcuate slot 46 formed in an arm 49 that is part of a rocker 50 loosely mounted upon a stud 5| projecting from frame N). This slot 48 is concentric with the axis of pintle 43 when bellcrank 35 is at the'limit of its movement away from rocker 50. j

The rocker 50 also includes a second arm 52 carrying a roll 53 that occupies a cam groove 54 formed in one face of a gear 55 fast on main shaft 23. This gear acts through the usual mechanism, not shown, to operate the whirl or loop'er of the horn 24.

During the operation of the machine the cam groove 54 acts to vibrate the rocker 50 and the latter acts through the link 46 and clutch lever 4| to swing bell-crank 35 back and forth on the tongue 30.

axis of shaft 20 thereby to slightly raise and lower the presser-bar 26 in timed relation with the vertical movements of the needle-bar II and also in timed relation with the feed strokes of the feed These limited movements of the presser-bar 26 during the sewing operation are accompanied by slight displacement of the fulcrum block l1, within slot I6, Fig. 8, but this is negligible.

- As shown in Figs. 1 and 9, the presser-bar 26 is made intermediate its ends with a second rigid laterally projecting arm 56 whichserves as an abutment seat for one end of a coiled spring 51.

The opposite end of this spring is seated against "clear that screw 59 may be adjusted to regulate the normaldownward pressure of spring 51 on presser-bar 26.

A block 60, Fig. 9, fastened in position upon the rear side of the upper end portion of the presserbar 26 serves as a stop which engages the top wall of frame Hi to limit the downward movement of the presser-bar when there is no work upon the horn 24 and bell-crank 35 is at the limit of its movement toward the presser-bar.

When the clutch lever 4| is pulled toward the right by link 46 Fig. 9, the spring 44 yieldingly restrains the lower end of said lever with the result that the two clutch blocks 31 and '40 grip the arcuate flange 39 of said lever between them thus swinging the bell-crank 35 toward the right, the clutch lever and bell-crank moving in that direction as one. When the bell-crank is thus swung toward the right it acts through the pintle 34 to slightly lift the presser-bar 26 against the pressure of the spring 51, and said presser-bar occupies this elevated position duringthe time that the feed tongue 30, Fig. 1, is making its workfeeding stroke toward the left. Immediately after the completion of the work-feeding stroke of tongue 30 the bell-crank 35 andclutch lever 4| are swungas one toward the left, Fig. 9, by cam 54 acting through rocker 50 and link 46 until a pin 6| projecting from the exposed side of block 31 engages an adjustable abutment screw 62 on frame l0. Thereafter continued movement of link 46 toward the left swings the clutch lever 4| independently on pintle'42 thereby unclutching blocks 31 and 40 from the arcuate flange 39 and permitting the spring 51 to yieldingly hold the foot of the presser-bar against the work.

a The cam 54 is constructed so that at the conclusion of about two hundred degrees of movement of both cams 54 and 22 from the positions shown in Figs. Band 9 the needle-bar is at the limit of its upward movement and the pin BI is against abutment screw 62. Therefore, at that time the presser-bar is free" to be lifted manually, and bell-crank 35 is free to be swung therewith toward the right, Fig. 9, independently of clutch lever 4|, to permit the work to be placed in position on the horn 24 or removed therefrom.

It will also be clear that whatever be the thickness ofthe work the clutch lever 4| and bellcrank 35 will always cooperate to function as above described, viz., to raise the presser-bar during the feed stroke, of tongue 30 and to free the presser-bar so that it can be manually lifted while the needle-baris at the upper end of its stroke.

Pivotally mounted at 63 upon the exterior of one of the side walls of frame |3 is a lever 64 having a forwardly extending arm provided with lol - strokeof the needle-bar will correspond to; and vary with, the thickness of the work so that the loop drawn up by the needle is always of a length alaterally extending end. portionroccupying a position immediately beneath a vertical plunger 65 slidably. mounted within a bearing provided in the bottom wall of the fram e.,The upper end of this plunger occupies'a position immediately beneath the arm 32 of the presser-ebar'. The lever is also provided with a r'earwardly extending arm to the free end of which is .connectedthe upperend ofla rod BBwhose lowerend is"[con-. nected with a foot treadle, that is not shown.

When this treadle is depressed it act'sthrough rod,

66, lever 64 and plungerlii to raise the presser-bar 26 thereby to permit the work to beflplaced in position onthe horn or.to,be removed therei from.

.8, and the, pivotal connection It: will vary with work of different thicknesses,.beingcornparatively great when the work is thick andromparatively small when the work is thin, andjas' a result the that is proportionate and appropriate to the thickness of the work. V

The cast-off element 61 is a rod or,bar of small diameter slidably confined within a longitudinal groove 68, Figs. 2, 3 and 8, formed in thenee'dlebar H atfone side thereof. The upper end por tion of the cast-off ,bar occupies a position within a -reces's formed in onesideof thejreedle-bar as best' shown inFigI 2 and has fixed thereon a head 69 having a flat side fitting against the flat bottom wall '|0-of said recess thereby to hold'thecast-ofi bar againstTrotationwithin its groove. I Directly beneath the headGQ is one arm of a small bellcrank lever 1| fulcrumed at 12 on an arm 13 extending downwardly from and form-' ing part of the collar l2 ofthe needle-bar The other arm of bell-crank H extends upwardly from fulcrum 12 and is'connected by astifi wire link 14,. Figs. 4, 8 and 9, with the lower end oi arm- 5 2 of the rocker 50.

1 During the operation of the machinethe vibratory movements imparted to rocker 50 act through link 14 and bell-crank II to shift the cast-oil Glrelatively to the ne'edleflaar, said castoff being moved in one direction bythe bell-crank and in the opposite direction by a wire bowspring 15. One. arm of spring 15 bears against the underside of collar 12 and the other arm against the top of the head 59 of the cast-off. v During the downward movement of the needlebar toward the position shown in Fig. '7, thecam 54.'Fig. .9, acts through rocker 50; link 14 and bell-crank" to hold the cast-off 61 above the hook of needle 25'with the result that as the needle is driven through the work and into'the horn 24 where the whirl or looper of the latter lays the thread of the next loop around the same as usual, the preceding loop remaining above the work'so that said next loop is pulled through it when the needle moves upwardly.

While the needle dwells in its lowest position shown in Fig. '7; the cam 54 swingsbell-crank a relatively piece of .work is upon.

ll away from the head 69 of the cast-off which permits the bow. spring 15 yieldingly to press and holdthe cast-off against the'workW where it remains until the hook of the needle emerges from the work as the needle-bar israis'ed. 1

During the upward movement of. the' needle bar the cast-off covers the hook of j the needle but after the. arrival of the needle-bar at the limit of its upward movement the cam 54 acts through rocker 50, link 14 and bell-crank !l to continue the upward movement of the cast-off thereby uncovering the hook of theneedle preparatory to the descent of the needle-bar. t t t v I Thereafter the'needle-bar and cast-off descend as onewith the hook of the needle uncovered until the parts are again in the positions shown in Fig. 7. M

The c'ast-oifis an important elementin'a'machine of this class and unless it is operated properly andwith certaintyto cover and uncover the hook of the needle the machine will not function properly and will cause considerable breakage of thread. Heretofore the cast-off haslnee'nactiv ated and controlled by a friction device which re-' quired continually to be adjusted'to take up for wear and which required to be particularly adjusted for the particular speed at whichfthe machinerwas operated. I

My new cast-off is operated positively bythe' cam ,54 in one direction while its movement in the opposite direction under the influencejof the bow spring 15 is also positively controlled by said cam. This'model of operation is wholly new so far as I know.

' 'It" is also a novel feature of thismachine that l a single cam-actuated member, such a s'rocker 50, serves to control and operate both the cast-off and the presser-bar. H

In my improved machineialso 'the presser-bar is connected with its actuating and controlling cam through a lever and africtionclutch carried thereby and it is a feature of the inventionthat at one end of the stroke of this lever the friction clutch, through engagement with a stationary abutment, is unset and that this unsetting ofjthe clutch occurs while theneedle-bar. is at the end of its upward stroke so that the. pressereb'ar' is then free to fb. manually lifted. The friction clutch remains' unset until completion of the downward vmovement of the needle-bar and then duringthe upward movement of the needle bar. the friction clutch moyes 'away' from the sta--' tionary abutment and isthereby automatically set" so that it' acts through the lev: r to; lift the presser bar and holdit away from the work while the latter is fed forward for the next stitch.

It is a feature of the above described needle bar operatingmechanism that'the triangular cam 22 gives the same length of dwell to the needle bar at the lower "end of its stroke whatev :r be the lcngth of the latter. whereas heretofore this period of dwell was varied when the stroke of the ne dle was varied to make it appropriate to the thickness of the work bein operated upon. That lSJhOICtOfOI'C, when the stroke of the needle was incr ased fort-bicker work the period; of rest during which the loop'er or whirl of the horn 'w'as-opera'tedwas sometimes shortened to such an'e'xtent as to require speedngup the looper. This objectionable feature is obviated by my new nee die-bar operating mechanism.

It will also b observed that the same lever 35 which carriesthe friction clutch and through which the presser-bar is operated by c'arn 54 also serves as the meansthrough'which the presserbar acts to adjust the needle-bar operating mechanism so as to vary the stroke of the. needle-bar when the thickness of the work varies thereby to maintain the length of the loop always propor-v tionate to said thickness.

The I feed tongue 30 is slidably and pivotally connected with the usual cam plate 16 fast on presser-bar 26 by. means of .a, bolt 11 which also serves to pivotally connect one end of the usual link 18 with said tongue. The oppositeend of link .18 is pivotally connected at 19, Fig. 1, with one arm of a lever fulcrumed at 8| and having its opposite arm pivotally connected at 82 with an arm 83 fast on a horizontal rockshaft 84, Fig. 6. This rockshaft is journaled in bearings provided upon the upper side of the bottom wall of the housing l0 and is also provided with another arm 85 carryinga oamvroll 86 that is engaged by a cam 81,011 main shaft 23.

The upper 1nd of the feed tongue 30 co-operates as usual with an abutment pin 88, Fig. 1, carried by presser-bar 26, said upper end being yieldingly urged toward said pin by a spring 89 one end of which is fastened to the feed tongue above bolt "and the opposite end to lever 80.

L:.ver 80 is formed with an arcuate slot 90 within which is slidably mounted an apertured block 9| through which the fulcrum pintle 8| extends. Pintle BI is carried by the arms of a forked bracket 92 rigidly'fastened bya screw 93 to the frame In. I

When the feed tongue 30 occupies its retracted position shown in Figure 1 the slot 90 is concentric with the axis of screw 93 and by loosening said screw the fulcrum 'of lever 80 may be adjusted lengthwise of slot 90 without disturbing the position' of the feed tongue. This fulcrum adjustment is made when it is desired to vary the length 7 of the work-feeding stroke of tongue 30.

" relieved by cam 54 during the upward movement of the-needle-barand while tongue 30 makes its work-feeding stroke whichoccurs' while the needle-bar is near the limit of its upward movement. The return of the tongue 30' to its normal retracted position is effected while the needle-bar is at the limit of its upward movement.

The pivot boltll, Fig. 9, maybe manually adjusted lengthwise'oi' slot 48 as desired or necessary to regulate and determine the action of cam 54 on the presser-bar. centric with pintle 43 when the presser-bar occupies its lowermost position so that the only effect of adjusting pivot bolt 1" .as described is to vary the height to which the presser-bar is lifted by cam 54 for any given adjustedposition .of abutment screw 82.

What I claim is:

1. A sewing machine of the class described having, in combination, a work-support; a needle-bar movable toward and from said work support; a power transmitting lever whereof one end is connectedvwith said needle-bar; a cam cooperatively associated with the opposite. end of said lever for vibrating the latter thereby to cause the same to reciprocate said needle-bar toward and from said work-support so that it dwells for a period of time at each end of its stroke: a driven shaft on which said cam is mounted, and a shiftable fulcrum for said power-transmitting lever that is adjustable relatively to said lever Theslot 48 is made con-H toward and from said cam so as to vary the length of the stroke of the needle-bar without changing the position occupied by the latter when it is at the limit of its movement toward said work-support andtwithout variation in the length of time said 'needle-bar dwells at said limit.

I 2. A sewing machine of the class described having, in combination, a work-support; a presser-bar movable toward and from said worksllppoit; a needle-bar movable toward and from said work-support; a lever connected with said needle-bar; a cam for vibrating said lever thereby to cause the same to reciprocate said needlebar toward and from said work-support so that it dwells for a period of time at each end of its stroke; a driven shaft on which said cam is mounted; a shiftable fulcrum for said lever that is adjustable relatively to said lever so as to vary the length of stroke of the needle-bar without changing the position occupied by the latter when it is at the limit of its movement toward said work-support and without variation in the length of time said needle-bar dwells at said limit, and means through which said presser-bar acts to adjust and set said fulcrum to cause said lever to impart a length of stroke to said needle-bar thatis proportionate and appropriate to the thickness of the work being operated upon as detected by said presser-bar. I

' 3. A sewing machine of theclass described having, in combination, a work-support; a *eedlebar movable toward and from said work Jupport; a power-transmitting lever connected with said needle-bar; an approximately triangular equilateral-cam for vibrating said lever thereby to cause the same to reciprocate said needle-bar toward and from said work-support so that it dwells for a period'of time at each end of its stroke; a driven shaft on which said cam is mounted, and a shiftable fulcrum for said powertransmitti'ng lever that is adjustable relatively to said lever toward and from Said cam so as to vary the length of the stroke of the needle-bar without changing the position occupied by the latter when it is at the limit of its movement toward said work-support and without'variation in-the length of time said needle-bar dwells at said limit.

4. A sewing machine of the class described having, in combination, a work-support; a presserbar movable toward and from said work-support; a needle-bar movable toward and from said worksupport; a lever connected with said-needle-bar; an approximately triangular equilateral cam for vibrating said lever thereby to cause the same to reciprocate said needle-bar toward and from said work-support so that it dwells for a period of time at each end of its stroke; a driven shaft on which said cam isrnounted; a shiftable fulcrum for said lever that is adjustable relatively to said lever so as to vary the length of stroke of the needle-bar without changing the position occupied by the latter'when it is at the limit of its movement toward said work-support and without variation in the length of time said needle-bar dwells at said limit, and means through which said presser-bar acts to adjust and set said fulcrum to cause said lever to impart a length of stroke to said needle-bar that is proportionate and appropriate to the thickness of the work geing operated upon as detected by'said presser 5. A sewing machine of the character described having, in combination, a work-support; a needle-bar movable toward and from said workwithout change in the position support; a lever having one end thereof connected with said needle-bansaid lever having its opposite end portion provided witha straight longitudinally disposed slot and its intermediate portion Iormedwith a longitudinally disposed arcuate slot; an approximately triangular equilateral cam disposed within said straight slot and continuously in engagement with the opposite sides thereof, said'cam' being operable to vibrate said lever thereby to cause the same to reciprocate said needle-bar toward and from said worksupport so that it dwells for a period of time at eachen'd of its stroke; a driven shaft on which said cam is mounted; an arcuate fulcrum block slidably mounted within said arcuate slot; a fulcrum arm having one end thereof pivotally connected with said block, said fulcrum arm being supported so that it is angularly adjustable on a pivot with respect to which said arcuate slot is concentric when said needle-bar is at the limit of its movement toward said work-support, and means through which the work being operated upon acts to angularly position said fulcrum arm so that the length of the stroke imparted to said needle bar by said lever is proportionate and appropriate to the thickness of said work.

6. A sewing machine of the class described having, in combination, a work-support; a presserbar movable toward and from said work-support; a needle-bar movable toward and from said work-support; mechanism for positively reciprocating said needle-bar, said mechanism including a power-transmitting lever and a fulcrum for said lever that is adjustable to vary the length of stroke of said needle-bar without change in the position thereof when at the limit of its movement toward said work-support; a movable member through which said presser-bar acts to adjust and set said fulcrum according to the thickness of the work being operated upon; a driven shaft; means operated by said shaft for intermittently feeding the work forward in timed relation with the movements of said needle-bar, and means through which said shaft periodically operates said member thereby to raise said presser-bar while the work is being fed forward.

7. A sewing machine of the character described constructed in accordance with claim 6 wherein said last mentioned means comprises a cam fast on said driven shaft; a clutch device supported by said movable member and shifted bodily back and forth by said cam in timed relation with the operation of said work feeding means, said device operating, when shifted by said cam in one direction, to grip and adjust said movable member thereby to lift said presser-bar and when shifted by said cam in the opposite direction to adjust said movable member so as to restore said presser-bar to its lowermost position again, and stationarily supported means for engaging said clutch device and maintaining the same unset while the latter is at the limit of its movement in said opposite direction.

8. A sewing machine of the character described having, in combination, a work-support; a presser-bar movable toward and from said work-support; a spring urging said presser-bar toward said work-support; a needle-bar movable toward and from said work-support; mechanism for positively controlling and reciprocating said needle-bar, said mechanism including a lever and a fulcrum for said lever that is adjustable to vary the length of the stroke of said needle-bar thereof when at the limit of its movement toward said work-support; a movable member through which said presser-bar acts to adjust and set said fulcrum according to the thickness of the work being operatedupon; a driven shaft; means operated by said shaft for intermittently feeding the work forward in timed relation with themovements of said needlebar; a clutch device slidably supported by said movable member; means through which said shaft acts to shift said clutch device bodily back and, forth in a direction parallel with thepath of said movable member and in timed relation with the operationof said needle-bar and said work-feeding means, said device operating when shifted in one direction to grip and adjust said movable member thereby to lift said presser-bar and when shifted in the opposite direction to adjust said movable member so as to restore said presser-bar to its lowermost position again, and stationarily supported means for engaging said clutch device and maintaining the same unset while the latter isat the limit of its movement in said opposite direction.

9. A sewing machine of the class described having, in combination, a work-support; a needlebar movable endwise toward and from said worksupport; a driven shaft; mechanism through which said shaft acts to reciprocate said needle,- bar; a cast-off slidably mounted upon said needlebar; a spring for'urging said cast-oil toward said work-support; an operating lever for raising said cast-off relatively to said needle-bar, said lever being pivotally mounted upon said needle-bar, and mechanism connecting said member and shaft through which the latter acts to control and actuate said member thereby to adjust said cast-off relatively to said needle-bar in timed.

relation with respect to the movements of the latter.

10. A sewing machine of the character described having, in combination, a work-support; a needle-bar movable endwise toward and from said work-support; a driven shaft; mechanism through which said shaft acts to reciprocate said needle bar; a cast-oil slidably mounted upon said needle-bar; a spring carried by said needle-bar for urging said cast-oil toward said work-support; a bell-crank for operating said cast-oil, said bell-crank being pivotally mounted on said needle-bar, and means connecting said bellcrank and shaft through which the latter acts to positively control and actuate said bell-crank thereby to adjust said cast-off relatively to said needle-bar in timed relation with respect to the movements of the latter.

11. A sewing machine of the character described having, in combination, a work-support;

a presser-bar movable endwise toward and from said work-support;a spring urging said presserbar toward said work-support; a needle-bar movable endwise toward and from said work-support; a driven shaft; mechanism through which said shaft acts to reciprocate said needle-bar, said mechanism being adjustable to vary the length of the stroke of said needle-bar; a movable memher through which said presser-bar acts to adjust and set said mechanism according to the thickness of the work being operated upon; means operated by said shaft for intermittently feeding the work forward in timed relation with respect to the movements of said needle-bar; a clutch device slidably supported by said movable member; a cam on said driven shaft; a rocker that is actuated by said cam in timed relation with respect to the operation of. said work feeding means; a link through which said rocker acts to shift said clutch device bodily back and forth in a direction parallel withthe path of said movable member, said device operating when shifted in one direction to grip and adjust said movable member thereby to lift said presser-bar and when shifted in the opposite direction to adjust said movable member so as to restore said presser-bar to its lowermost position again; stationarily supported means for engaging said clutch device and maintaining the same un-set while it is at the limit of its movement in said opposite direction; a cast-oil 'slidably mounted on said needle-bar; a spring urging said cast-oi! toward said work-support; a bell-crank for operating saidcast-oil, said bell-crank being pivotaliy mounted upon said needle-bar, and a link connecting said bell-crank, andv rocker through which the latter acts to operate the former in timed relation with respect to the movements otthe needle-bar.

WALTER PEARSON.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2692569 *Sep 14, 1949Oct 26, 1954Ketterer Stanley JNeedle stabilizer
US3779187 *Dec 13, 1972Dec 18, 1973Singer CoSewing machine with hook timing and skip stitch mechanisms
US4714037 *Aug 12, 1981Dec 22, 1987The Singer CompanyNeedle looper assembly for non-threaded needle lockstitching
US4757775 *Nov 19, 1986Jul 19, 1988Mts Systems CorporationChain stitching apparatus
Classifications
U.S. Classification112/34, 112/221, 112/56
International ClassificationD05B15/00
Cooperative ClassificationD05B15/00
European ClassificationD05B15/00