US1333594A - -allen - Google Patents

Description

E. B: ALLEN. THREAD CUTTING MECHANISM FOR SEWING MACHINES.

APPLICATION UL!!! 11.29. 1915. 1,333,594.

6 SHEETS-SHEET l.

Patented Mar. 16, 1920.

" A HORNE) 0R SEWING MACHINES.

APPLICATION FILED MAR. 29, 19'5- 1,333 594. Patented Mar. 16, 1920.

6 SHEETS-SHET 2.

Irma- E. B. ALLEN.

THREAD CUTTING MECHANISM FOR SEWING MACHINES. APPLICATION FILED mmzs. 191s.

1,333,594 Patented Mar. 16, 1920.

6 -SHEETSSHEET 3.

(D (Q gjfw, i I U g E} I I I II N a; 5:1 Q I I Q h N 1N f fi 0 gI I a b: r 1;;

INVENTOR E. B. ALLEN. THREAD CUTTING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED MM'LZ9. l9!5. 1,333,594.

Patented Mar. 16, 1920.

6 SHEETS-SHEET 4.

E, B. ALLEN.

Patented Mar. 16, 1920.

6 SHEETS-SHEET 5.

INl/EN TOR m/QM atented Mar. 16, 1920.

E. B. ALLEN.

THREAD CUTTING MECHANISM FOR SEWING MACHINES.

APPLICA'HON FILED MAR. 29, I915.

UNITED sTAr s PATENT OFFICE.

EDWARD B. ALLEN. OF BBIDGEPOET. CONNECTICUT, ASSIGNOR TO THE SINGER. SEWING MACHINE COMPANY. A COB-PORTION OF NEW ER-5E2.

l .I I 3.594.

Specification of Letters Patent.

Patented Mar. 16, 1920.

Application filed latch 29, 1915. Serial Ito-17.585.

To all who: it I/I/I l/ com-( m:

Be it lillUWIl that I. Emunn B. ALLEN. a citizen of the l'nitcd b'tatca. residing at Bridgeport. in the county oft-airfield and State of'tonnccticnt. have invented certain new and useful Improvements in Thread- (ntting .\lechani.-n1. for Sewingfilachinca. of which the following is a spe ification. rcfercncc being had therein to the accoin panjving drawings.

Thiinvention relate nlmc particularly to thread-cutting means for that chi of t' lllfl machines adapted for production of detached .-uct'e. .\ion. or group of stitch; and it hm for its primal"; ohject the production in a -inglc operation of a group of stitches. such as thow all'ording a hinding for the edges of a hnttonhole slit. with the ends of the stitching thread or threads conccaled from the nppcr face of the work. and preferably by the covering of one or hoth ends of the thrczid in" mpcrposcd stitchc In its preferred f rm. the invention is cuthodied in a machine provided with a workhohlcr coinprhing a lower member and an upper lnenlhcr in the form of a clamping foot pivotallv mounted thereon and provided with a plurality of recesses parfillel with thc work-engaging face of the foot." 'ithin one f said recesses is preferably dis iosed a comhined nippiu; and cutting hla e operative reapcctively in conjunction with the upper and lower walls of said recess. while an an.\'- iliary cutting,' blade is disposed in an adjacent. |;ecess in a path substantially coincident with the work-engagino face of the clampinglfoot. The said hadcs are prcferah y niqilnted upon independent fulcra and r ceive their operative or thread-engaging movements from sllitnhlc springs in oppositipn to which they are both retracted by means applied to the one and acting through ill upon the other. Said blades are mamtained in retracted position by means of independent latches which are disengaged to parpiit nipping and cutting act ons. the one hy tneans acting at the completion of a buttonhole stitching operation and the other by means operative in the initial portionpf the stitching operation. the former serving to sever the stitchin thread leading from the work to the need at'the completion of a stitching period. while the other cuts otl' close to the work the l00se end of needlethread used in starting the stitching operation.

During the prima thread-cutting action. the thread leads com the nipping derice to the eye of the needle 0 that the portion of thread detached from the work is then wholly above the nipping elements; hut in the de r-cut of the needle for production of the first stitch of a succeeding grou the thread is led by the needle downward y through the work and over the rearward edges of the cnttin elements. Thu in the retraction of the hFadcs succeeding the second cutting action. the short end of thread cvcrcd from the work is forcibly carried hack-ward in it simultaneous release b the nipping elements and deposited lateral y of the work-holder and the nipping device'is thus cli'cctively cleared of thread so that an :n'cumnlation thereof. which would impair the etl'cctiveness of the device in subsequent nipping actions. mechanically prevented. To insure that the loose thread may not. be sllhseqllclllly introduced within the range'of action of the stitch-forming devices by the jarring of the work-holder in the stitching opt-ration. or by other means. a blower is preferably provided for ap lying an air-jet to the clamping foot, there providing for the discharge of the detac ed sections of thread from proximity to the stitch-forming devices.

In the accompanying drawin the prcsent invention is shown embodi in an eyelet-end bnttonhole cutting and stitchin mnchinc constructed in substantial acoo 'ance with my I'nited States Patent No. 1.048.786. of Deceinhcr 31. 1912. and my Patent No. 1.240.642. of September 18, 1917.

Figure l is a rear side elevation of the machine. Fig. 2 a )lt'tfl thereof with the overhanging arm 0 the frame removed to expose parts beneath the same. and Fig. 3 ion bottom lan of the machine. Fig. 4 iso lan view oi the feed-whee]. the work-ho der carrying slide-plate connected therewith 00 and a part of the stop-motion with its tripping means. Fig. 5 IS a plan of the tensiondcvice with its releasing means andgthe ncedle thread pull-oil device. Fi G' fis a face view of the belt-wheel with t e clutch constituting a part of the stop-motion device. and Fig. 7 an edge view of one of the clutch elements. Fig. 8 is a rear and elevation of the lower portion of the machine, with the base in section.

Fig. 9 is an elevation representing'the work-holder with the operating means of the rimary thread-cuttin and nippin devices in diflerent positions rom those Fig. 1. Fig. 10 is a plan and Fig. 11 an elevation, upon a larger scale, of one of thepairs of work-clamping elements composin the work-holder, allowing the thread-mp ing and cutting eviees with parts of t eir operating meims. Fig. 12 is a bottom view 0 a portion of the work-clamping foot with the thread-cutting and nipping elements, Fig. 13 is antelevation of the same taken from the front edge, and Fig. 14 is an elevation of the same taken from the rear edge and with the clamping foot in section. Fig. 15 is a. representation in face and edge view of the latch for the auxiliary thread-cutting; blade. Fig. 16 represents in edge and face view the com ount thread-nipping and cutting blade. g). 16 is a face view of thc thread-nipping lade-section. Fig. 1? represents inface and edge views the auxiliary cutting blade. Fig. 18 is a plan of the trip pin cam-block for the auxiliary threadcutting blade. Fig. 19 is a front end view of the air-pump and its supporting and actuating means.

The machine frame is shown constructed with the usual hollow base 1 from the rear end of which rises the hollow standard 2 providedv with the overhanging tubular member 3. Within suitable hearings l is journaled the transverse cntteHu-tuating shaft 5 disposed in the lower portion of the standard 2 and having mountcd looscly upon its forward end the grooved belt-wheel (i embraced by the driving belt 7 leading from the source of power. As fully disclosed in my said Patent xo. 1,048.781, a suitable clutch is provided for connectinp the cutter-shaft 5 with ..the actuating beltwheel 6 for a single rotation of the latter in each buttonhole producing cyclc: and the shaft 5 is provided with suitable cams for im artingtilting movculcnts to the up wr ant lower cutter-carrying level-sh and and for imparting traveling movements to their fulcrum-sustainim; slide-block 10.

The'main-shaft 11 is journaled within and longitudinally of the base 1 and carries adjacent its forward bcarin r the cam-cylimler 12 with groove 13 cutcret by the roller-stud l4 depc uli'ng from the lever 15 swinging upon a fixed fulcrum and conncctcd by the link 16 with tlic clutch-lcvcr l7 actuating thc cramping clutch-dogs l8 having jaws embracing the dcpending flangc I! of the feed-wheel 20.

The feed-wheel has in its upper face the usual feed-cam. groove 21 and side-shift groove 22, the former of which is entered by the roller-stud 23 depending from the swingin lever 24,- which is mounted upon a fixed fu crum and is provided with the u wardly extending stud 25 coaxial with tiie stud 23 entering the transverse slot 213' of the slide-frame 27 movable in suitable guideways of the bed 1. Movably fitted to suit" able transverse guides of the slide-frame 27 is the slide- )late '28 having upon its under side the bloclt '29 formed with a longitudinal guidcway cntercd by the -stud 50 of one end of tho. rock-lever 31 having a iixcd fulcrum intcrmediatc its ends and provided at its opposite end with the roller-stud 3'2 entering the side-shift cam-groove 22.

Mounted upon and at the forward end of the slide-plate 28 by means of the pivotal ains 33 are the reciprocally movable clampplates 34 formed with serrated portions 35 which afford the lower work-cnggiging jaws of the work-holder opposed to which arc the serrated lower faces 36 of the clamping fcet 37 aii'ording the upper work-engaging jaws. The fect 37 are pivotally conncctcd in a manner well known with the forward ends of the spring clamp-arms 38 fulcruined at their opposite ends by means of pins 3 upon the bearing blocks 40 secured upon thc respective clamp-plates 34. Mounted within suitable hearings of the blocks 40 are the alined rock-shafts 41 each provided with a cam acting upon its rcsrc 'tivc clamp-arm 38 in oppositionto the li ting spring 42. The. rock-shafts 41 are connected together for movement in unison by; means of thc up wardly cxtcnding arms 43 and H. the one being provided with a latcral pin 43' cmbraccd by a fork 4-l' of the other.

The clamping foot 37 nearest the back of the machine is provided at its outcr end with an extension 45 for supporting the thrcad-cutting and nipping bladcs and the parts immediately counectcd thcrcwitlnsuch cxtcnsion or support being formed in its lowcr face with a rcccss 45' open at the bottom above which is a second rcccss 45". The cxtcnsion 45 is composed of spaced uppcr and lower platcs rigidly sccurcd togcthcr by the stud-screws 46 and 47 so as to be relatively yielding where the nipping and cutting blade enters the space hctwecn thcm and they arc yicldingly maintained a fixed distance apart at the nipping and cutting points by mcans of the spacing screwhcad 48.

Journalcd within an upwardly extending hcaringboss 49 of the foot-cxtcnsion 45 is a rocking iin 50 to the lowcr and of which is sccurod. lntcrmcdiate the bond of tho axial clamp-screw 51 and thc washcr 52. tho cnlarged hub portions of the overlapping hlmlc-sccti'onn 53 and 54 constituting a compound thread-nipping and cutting blade. maintained in fixed relation by means of the dowel-pin 55. The outer portion ofthe operative edge of the nipping blade 534$ ill) primary ment 53 first enacting nected one end'of a formed with a outward from t e adjacent portion to a an angle for guiding the thread to the nipping int, and has upon its opposite edge 5 a me 53" for catching the thread-section upon its disengagement fwm the relatively fixed nipping jaw so as to insure its removal from the letter in the retraction of the cutting and nipping elements. The edge of the cutting element 54 is formed beneath said angle of the nipping element with a concave ortion 5i I, nsure the severing of the tn'ead at the desired point in the length of the blade.

The component elements of the compound nip ing and cutting blade are constructed an operate substantially as shown and dcscribed in my United States- Patcut No. 885,310. of April 21, 1908, excepting in their 20 shapes which are made to accord with other parts of the present improvement. Thc compound blade 53 54 is adapted to move within and substantially till the space or slot 45" of the support 45. the upper ele- \'icldingly with the upper wall of the space 45" in. nipping the thread and the lower element 54. having its lower concaved operative edge sharpcncd. coacting substantially with the abrupt shoulder afforded by the lower and free edge of the space to sever the nipped thread. W'hile the nipping and primary thread-cutting elelnents are preferably constructed in separate Uections to facilitate their manufac- 35 ture and maintenance in operative condition, it is erldent that the blade need not be nside in separable sections, nor the clcmcnls referled to be relatively positioned and con nected for operative movement in unison aw A0 herein re resented.

Seen upon the upper end of the rocking pin is the hub 56 of the crank-arm 57 connected by means of the screw-pin 5* with the flattened forward portion 39 of a bent slide-rod 60 having its rearward portion slidingly fitted within the lug 61 extending laterally from the bearing block -lO. Secured upon the rod 60 is a collar 62 provided with a lateral pin 63 to which is com epring 64 hating lls opposite end attached to the perforated car 65 of the'lug 61. The spring 64 nornndly draws the rod backwardly to seat a collar 1 66 thereon upon the adjacent face offlie lug upon an interposed washer (l7. whereby the primary nipping and cutting hlade 53 5-1 isvmaintained yieldingly in advance or operative position. as represented in Fig. 12.

06 Secured upon the rod on intermediate the collars 62 and 66 by means of the set-screw 68 is a" block 69 carrying'a roller-stud 79 which is embraced by a fork 71 of the lower arm of a swinging lever 7:? fulcrumed intermediate its ends upon the rock-shaft 41 rtion 53 inclined ubruflptly ord .fulcmm point and having upon its upper end the lateral tooth 73 whose upper face is inclined upward]; and forwardly atlan acute angle with its adjacent face extendin toward the of the lever. T e movement of the latch-lever upon its fulcrum in opposition to the stress of the spring 64 obviously causes the endwisc movement of the rod 30 and the consequent letraction of the primary cutting and nipping elements prcpuratory to their action upon the needlethrcad at the completion of a stitching operation.

Journalcd upon the etudecrcw -16, or a spacing washer surrounding the same. internlcdiate the componcut plates of the clamping-foot extension 45 is the-hub H of the auxiliary cutting blade 75 which in downwardly oli'set from said hub in uch nmuncr :u to he movable in a path within the lower rcccse 45 of the clau1ping-fnot extension, The hlndc T5 luw ncur it! outer end a concave portion T5" which i Shar cncd to form a (lilting edge for severing: the initial cud of m cdlc-thrcud hauling from the work to the nipping dc iwx From the huh Tl cxtcml in angular relation with thc blade 7-" u lateral arm To formed with an angular shoulder or tooth T7.

The tooth T7 is :uiaptcd to he clurngcd in the hooked extremity To of a latch-arm constituting one mcmhcr of a plural-armed lever having-its hub portion journnlcd upon the stud-screw 44'. or a spacing washer surroumling the Hllllt. intcrlnmiiutcihc component plates: of the clumpingioot cxtcusion 45. The said lever is provided upon the opposite side of said huh with n curved tuppchnrm RI intcrmcdiatc which and the huh is another lateral arm 9:? formed with a groove 83 in its edge farthest from the arm 91. (oiled around a stud-screw Q4 tapped into the upper plate 4.3 is the body of n spring having one arm 86 rusting within the groovc 53 of the lcvermrm 92 and the other arm 97 bearing upon a pin 89 project lllg from the hub portion 74 of thc auxiliary cuttin, hlndc T5. By mcans of this spring. the auxiliary cutting clement T5 is normally prcsscd-toward its position of operative engagement with the thread and the latch-levcr arm 79 is pressed yicldinglv into engagement with thc arm 76 for detaining thc auxiliary cutting element in retracted position,

as represented in Fig. 10. l

The huh 7;} of the auxiliary cutting blade carries a second upwardly extending pin 89 whose upper end is disposed in thc path of movement of a canrplnte 90 whose upwardlv offset shank 91 is secured within a suitable transverse scat formed therefor in the top of the crank 57 by means of the fastening screw 92. In the turning of the rocking pin 50 for retraction of the primary cutting and ninping elements, the cum-plate 90 engngee the ltl tit

pin 89 and acts through the ame to shift the auxiliarv cutting hlade T3 into retracted position w irreiu it is held h the automatic cugagcmeul of the latch-arm iii with the lvnil'cltlttllt' arm T i. repre ented in Figs. 2 and It).

The rlanipmrui 258 i hown provided with an apertured hearing lu, $115 entered hv the forward portion of the heat trip-rod 'Jl whose forward extremity is disposed in alinement with the lutrlnlcvel' arm st. 'lhe flattened rearward end of this trip rod is pivotally connected li v mean of the stud J5 with the upper arm .Hi of an angle-lerer t'ulernued at it? upon the inner face of the hearing hlorl; l and haviu; a rear\\'ardl v extending arm 98 provided in its lower edge with a notch 90 with inclined rearward cam edge t lt the arm 91': lacing" pressed haul;- \vardl r for retraction ot' the triprod .H by means of a spring 1 1 sustained h the lvcaring liluek 411 The notched extremity of the auglwlever arm th norm-all re ts upon a swinging plate 102 piroted at mueud li meausof the tudscrew upon a liloel; 11H which is in turn sustained h a memlier of the hase 1 or some other part of the machine tixetl relatively to the travel of the work-holder. The plate 10-. has at one edge of its upper face the camtooth 10.) with its operative rearward face 105' upwardly and forwardly inclined similarly to the emu-edge Hit) of the notch J9. while its forward face um" is inwardly and lmelm'ardlv inclined. as represented particularly in Figs. 10 and 1 Secured to the end of the block 10-1 in means of the fastening I screw 106 is a spring to? having a bent arm HIS resting: against a stoppin [US] which is maintained normally in contact with a shoulder [10 att'oided hr the rahhet formed in the adjacent edge of the lilorlz 101. as rep resented in dotted line in Fig. 1h.

.\t the beginning of a stitching operation, the t'ttltl'itltitll 105 is embraced hy the notch .19 of the angle-lever arm 1th with its opera tire face 105' slightly spaced from the cam edge of the notch tit), as represented in Figs. 10 and 11.

In the travel of the work-holder. and with it the angle-lever 96 9B. during the production of the first few stitches of a huttonhole. the cam-edg 101) em-ounters the face of the cam-tooth 105 and ridesup the latter whereby the angle-lever is tilted and the. trip-rod SH moved into engagement with the latrh-lerer arm til. thereby tilting the latch lever and releasing the auxiliary cutting blade which performs under the action of the spring-arm 8? an operative threiula-mering movement across the lead of the thread end extending from the work to the aipper, therehv cutting ofi' the same. close to the. work. This operative movement is arrested by encounter of the head of a stop-screw" 111 carried by an extension of the huh 74 with the upper clamp-toot exten ion-plate 45. The arm t -H having ridden over the cam-tooth lll." routinues to more to the end f it forward trawl and then performs its retrograde movement with the work-holder. As ilexttelull) encounters the laterally 'mclined I'm-e m3" of the ram-tooth. it thrusts the same a ide in opposition to its spring los as represented in Fig. 15, and upon resuming initial po ition allows the cam-tooth to nap into its l'ull line position (Fig. 18) in readiness for a succeeding tripping action.

The stitrh-forming mechanism of the mat'llllll' It'llltfl'lltitl in the drawings is snhstantiallr the same as that of my Patent No. Latino-Ht, ot .lune I 1912. as is also the. mean for turning the same. in the stitching ot the eyelet-end ol' the huttonholc. The turning means comprise the eudwise movalile lide-liars 11; and 112i journaled in suital-le hearing su tained luv the frame above and lielow the work-clamp and connected for uunement in unison l) means of the llltllllttl 1H. While these slide-liars derive their endwise movements from a connection with the eam-wlieel '30 provided in its upper face with feed-actuating ram-grooves, as disclosed more fully in said patent. such movements are obviously efi'ected independently of the particular feeding motion defined by said cam-grooves and imparted to the traveling worleholder. The upper slidehar 112 has fixed thereon the collar 11?) prorided with the lateralljv and forwardly extending ltlg' 11G *arryiug the stud-screw 117.

Vulcrumed upon the stud-screw 111' intermediate its ends is a rock-lever formed with the arched and forwardLv extending latch-arm 118 having the hooked forward extremity ll!) attordiing a shoulder for engagement with the upper extremity of the sivinginp lcver T2. and provided with a rearwin'dlv extending arm 12h notched in the extremity of its upper side to receive the stop-screw 1'21 tapped into thecollar 115 against which it: is normally held by means of the swing 122 having one arm resting upon tie. lever-arm 118 and the other upon the lug 116. The lever-arm 120 earrieatho upwardly extending contact-pin 123 which may he in practice tapped into a threaded aperture of said arm and secured in the, desired position of adjustment liy IlNi as of the set-nut 124.

The stopanotion of the present; machine is or may be constructed substantially in accordance with thatof in) said Patent X0. 1,048,786. Adjacent the loo e driving pulley 125 is secured upon the maiushaft tt'thc lltll) 126 of the clutch-wheel or disk 12? recessed at one portion at its periphery for the reception of theelutch-plate 128. said wheel having a segmental recess to receive the cam projection 1'39 of the, clutchlit) ring 130. The clutch-wheel 1:27 has in its outer face a seglm-ntal recess to receive the butler-spring 131 interposed between one end of'said recess and a stud 132 projecting from the inner face of the clutch-rin 130 normally' resting against a shoulder a orded by the opposite end of said rec-em. The clutchring is provided with an eccentric or cam pro ection 133 terminating near the. peripher of the clutch-ring in the notch 134 utthe opposite side of which the clutchringzfifiiprovided with a lateral cam ined in the bracket 136 secured upon 5 1 is the rock-shaft 13? upon which he hub of the tilting stop lever 138 arrying a spring-pressed block 139 which i 8 formed: with the tooth 140 adapted to enter-the peri heral notch 13-1 of the clutchdisk 130. T e stop-lever 138 is normally maintained in operative relation with the oliit h disk by means of the spring 141, intefposed between the base of the standard 2 and a lateral extension 142 at the upper end of the stop-levciu The rock-shaft 137 has secured thereon the forwardly extend- ;ing arm143 earl-Yin? the roller 144 normally lying in the path 0 movement of the cumsector 145' carried by one of the CttllbdlsliS 145fixed upon the cutter-shaft 5 by means which the stop-lever 138 is tilted 1n oppogsition to its spring as the cutter-shaft completes a rotation for actuation of the butto ole cutter. f .Mounted upon a fixed fulcrum within the base 1 is the upwardly extending arched pawl-lever 146 whose depending uiper extrelnit rests normally upon the si e of the lever 'l 43 under the action of the spring {9147 and is adapted to move above and in ,jlatching relation therewith whcu said lever ails depressed. Disposed closely adjacent to the head of the pawl-lever is the extremity of. one arm of a tripping lever 148 ful- 46 crum'ed at 1-19 and huvin its other arm provided with theui djustuhle contnctpiccc 150 adapted for engagement by the usual tripping stud 151' carried by the feed-wheel 20 to 'ell'ect the release of the stoplcvcr 138 and its movement under the action of the 5 ring 141 into stoplping relation with the clinch-disk 130. e AIDQVGIIIBIH of the present the tooth 140 of the cam progfgtop-lever is timed to above the lower portio jectipn liiirwhich lifts 't 1} Game in opposition tofliits spring in the braking of; the

inai'ri-shiift'nnd finailiy descends in entering the peripheral notch 34, effecting the arrest of th clutch-disk and freeing the loose pullgywhel' 125 from the operative pres sure of the plate 128 under the action of the i izini jirevjection 129. v

NW" resented in Fig. 4, the cam-wheel 20 .iws own provided with a segmental series watdly extend by the forward end of thc rcciprocniii'ig pawl-bar 152 having its rearward cnd pivotall connected with the crankmrm 1.1.; of a rocking sleeve 154. The sleeve 15% h:|- a rcarwardl extending craukarm .15.", connectcd by a link 1.36 with a strap 157 cnibracing an uctuatin eccentric upon the hub of the loosc belt-wliccl 125. is dcscrilicd more fully in my Patent No. 1.024.490, of April 30, 1912, the pa wl-ba r 152 is controlled in its operative relation with the feed-whorl 20 by means of a plural-Mined rocker 1.78 with one arm of winch it I noction, while another arm of said mumis connected by means of a rod 15H with a stud 160 upon the rock-lever 138; whereby the movement of the rock-lever into and out of stopping Position causes the simultaneous movement 0 the pawlbar 152 into and out of operative relation with the feed-wheel in contact with the toothed peripheral portion of which it operates to complete a rotation inaugurated h the feeding mechanism comprising the c utch-dogs 18, during which final feed-wheel movement the stitching devices are turned into initial position after a stitching operation.

Mounted upon a lug 161 projecting from the cap-plate 162 of the tubular arm 3 is the tension-stud 163 provided with the tension disks 164 between one of which and the not 165 is the spring 166 which is controlled in its 0 ration by means of the axial release pusi pin 167 in a manner well known. The extremity of the pin 167 is adapted for enga emcnt by the inclined operative face of tfie depending head 168 of the tension release lock-lever 169 mounted intermediate its ends upon the fulcrum stud-screw 170 and having its rcarwardly extending arm pivotally connected by means of the screwqnn 171 with the depending bar 172 provided at its lower and with the lateral hp 173 formed with a slot 174 cmhracin the shank of the screw-stud 175 t; ppc into the lower portion of the standard 2. The bar'172 is normally drawn downwardly hfimeans of a spring 176 having one end booked in an aperture 177 of said bar and the other end attached to a stud 178 upon the standard 2.

Pivotally mounted. upon the enlarged lower portion of the bar 172 by means of the at tl-screw 179 is a plural-armed pawllever living a depending arm 180, an uping arm .181 and a rearwardly extending am 182, the latter rest ing normally upon the head of a. stop-screw 183 tapped into the bar 172 under the ac tion of the spring 184 carried by the bar 172 and having an arm resting edge of the pawl-lever arm 181. 'The lower end of the pawl-leverarm 180 is ada bed to rest upon a stud-pin 185 sustained y the forward arm of a rock-lever 186 fulcrumed has nyielding coni upon one intermediate its ends by means of the studscrew 187 upon the stop-lever extension 142 and having a rearwardly extending arm connected by means of the screw-pm 188 with the upper end of a bent link 189 connected at its lower end by means of the screw- )in 190 with the slide-block 139.

In tie position of the parts represented in Fig. 1, the block 139 is in its lower or stopping position, and the bar 172 is maintained in its upper position for holding the rock-lever 169 in tension-releasing position wherein the tension'disks-m'e relieved of the pressure of the tension-spring 166. The tilting of the stop-lever 138 to start the stitch-forming and feeding mechanisms carries the stud 185 from beneath the pawllever arm 180 and thereby removes the su port for the bar 172 which is caused to e scend under the action of its spring 176 for discontinuance of the operative engagement of the tension-release pm by the head of the rock-lever 169, thereby causing the tenslon- 5 )ring 166 to resume its normal action upon the tension-disks. The tripping of the stop-motion and consequent return of the stop-lever 138 to stopping position causes the backward movement of the rock-lever 186 and hence the engagement of the stud 185 with the forward edge of the pawllever arm 180 which opposition to its spring 184.

As the block 139 rises under the control of the cam-projection 133 of the clutclr disk 130, the lever 186 is rocked to bring the stud-pin 185 below the bottom of the pawl-lever arm 180 which snaps into normal position beneath the same. for positive engagei ient therewith iii the subsequent descent o the block 139 vs hen the tooth 40 enters the notch 134 of the clutch-disk 30 for final arre t of the main-shaft. The rise of the bar 17 of the roclelever 186 causes'the actuation of the tcnsioirrelease rock-lever 169 for again opening the tension.

As will be readily understood, it is desirable that the action of the tension upon the needle-thread be resumed preparatory to the beginning of the first stitch-forming cycle of a group. By the disengagement of the tension-mleasing bar 172 from its liftinn element'186 preparatory to the initial movement of the -n'iaiu-shaft, the tension .is closed upon, the thread at the by the action of the spring 176 upon the connected tension-release lever 169.

The tension-release rock-lever 169 carries a screw-pin 191 connecting with it the u pler endof the depending bent tri rod 152 avmg intermediate its ends an en argeinent provided with the slot 193 embracin the shank of the guiding screw-stud 19g and provided at its lower and with the backwardly oflset cam-head195 formed in its is thereby rocked in under the lifting movement same instant forward edge with the bevel 196 and adapted for engagement with the end of the contact-pin 123 carried by the latchlever arm 120.

As the machine is represented in Fig. 1, the cutter-shaft is in initial position at the completion of an operative rotation wherein the buttonhole cutter has been advanced into the range of action of the stitch-forming mechanism to cut a buttonhole ,and has been returned to initial position, and the clamp has been closed and s read. Sueceeding the engagement of tie camlute 145 with the roller 144 of the stop-t ever arm 143, the stop-lever would be in runn.ng position, but in order to show the stitch-forming and feeding mechanisms and their controlling means in initial sitior. the machine is represented as if t e stop motion had been immediately tripped aftei its actuation by the cam-plate 145.

As the stop-motion is set for stitchin the tension-release rock-lever 169 is tilte as before explained. and the trip-bar 192 is raised into its full-line position as represented partially in Fig. 9. In the initial forward travel of the work-holder, the lever 72 is carried into engagement with the shoulder of the latch-arm 118 and thereby receives a partial tilting movement, the major portion pf its throw being performed in the backward movement of the slide-bar 112 for turning the stitching mechanism in the stitching of theeye of the buttonhole. The lever 72 is detained substantially in this position throughout the remainder of the stitching operation, the thread-cutting elements having been thereby retracted as represented in Fig. 10. Upon the final action of the stop-motion at the end of a rot stitching operation, the tension is opened as before described and simultaneously there with the trip-bar 192 is thrust downwardly into engagement with the contact-pin 123 and 'the latch-lever 118 120 tilted, as represented in dotted lines in Fig. '9, for re-'- lease of the lever 72, thereby permittin the actuation of the primary nip ingi'an ent!" ting blade under the action 0 its actuating spring 64 for nipping and severing the' t read leading from he last stitch. The tripping of the auxili'hry' thread-cutter into not initial travel of the work-holder during the succeeding buttonhole-producing cycle, us'120 previously described.

Projecting laterally and upwardly horn a lug 197 upon the caplate 162 is a strict; i198 carrying the screw-pm 199' upon whi fulcrumed the rearward end of the ofl needle-e w ith i, a.

on is effected in the at its free cud a lateral extension 202 mow uhlc across the lead of the thread from the tension device to the top of the hollow nccdlc hnr, and its descent at the end of a stitching operation causes the. drawing of Slack thread through the tension device the initial stitch-forniing cycle of a succeed ing buttonhole stitching operation.

As represented in the drawings, the thread-cutter carrying clamping foot 37 has its lower plate 45 extended laterally beyond the upper plate at the side udjait-ent the fulcrunnstud -17. its edge being formed with a guard-rib or curb 203 extruding from one of the pivot lugs of the foot with the chimp arm 38 laterally and forwardly. as represe-nted particularly in Fig. It). Secured upon the forward are of the hearing block 40 for the other clamp-arm 35 is a bent tube 204 having a. contracted forward end to form a nozzle 205 disposed near the clmnpinpyfoot extension 4-5 a nd dire ted toward the range of mounnent of the tlncadcutting elements so reprq wntcrl p n;- ticularly in Fig. 2.

The opposite end of the tube 204 is con.' ncc'ted by the flexible tubing 206 with a. nipple atthe rearward cud of an air-pump cylinder 207 sustained by a. hanger 208 having u foot 209 which may be secured upon the bottom of the supporting table of the machine. The cylinder 207 has titmd therein (Fig. 2) apiston 210 whose plunger rod 211 is provided with a lateral arm 212 to which is connected one end of a. pitman 213 attached at its opposite end to ii crank pin 214 upon a grooved ulley 215 mounted upon a stud 216 cxten ing laterally from the hanger 208. The pulley 215 is disposed below the pulley 6 and in contact relation with its actuating belt 7 from the source of power from which it derives rotary move ment for imparting reciprocator movements to the piston through the ascribed connections. The operation of the piston 210 within the cylinder 207 cuses alternate m-fiow and out ow of air through the tubs, 204, thereby producing poll's of air upon and around the clamping feet and insuring the ejection of any loose matter in the vicinity of stitching elements through the chute rovided by the lower extension plate 4.3 an guard-rib 203.

In the operation of the machine, the clutch device of the cutter-shaft is first actuated to produce a's'ingle rotation of said shaft for cutting the button-hole. slit, closing and spreading the work-holder, and actuating the stop-motion for setting the stitclrforming and feeding mechanisms in operation. In the initial travel of the workholder, the auxiliary thread-cutting device is tripped into action. to sever close to the work the initial thread section extending from the work to the nipper.

for

"trolling its period of rrimul arm 118 with the shili lever 72. Upon the actuation of the stop-motiombo arrest the Stli(ll-f0lllll!tg and feeding; mechanisms, thc tension is ieleuscd, the pull ofi lever is actuated and the lutclrlever 118 120 re.-

trzicted to permit the actuation of the primary tllli'filti-Illllllllllg and cutting elementsupon the thread in the order named. The ford-wheel it having performed u. artiul rotation under the action of the clutc -dogs 18. complctcs the rotation under the of the pmr .-Jnu- 15? thereby returning thhf slidcdnus lit! and 113 to initial" retracted iosition. the former carr i with it the l y lsitclrlcvcr HR 120, and simultaneously turning the stitch-forming elements into their initial positions.

From the foregoing description it. will he observed that the present improvement; is not. limited to the specific construction and arrangement of the component tl'n'end-nipping means and the primary and auxil is ry cutting elements cooperating therewith. nor to the particular actuating and controlling! means therefor.

Haring thus set forth the nature of the invention. what- I claim herein is 1. In a sewing machine, in combination. stitclrforming mechanism, means for c0ntrolling its period of action, a work-holder comprisin members :1. plin'ality ot' thrmul-cntting dc vices mounted upon the upper clumpiiig mcn'ihcr. and means for actuating said thread-cutting devices successively in different stitclrforming cycles of a period.

2. In :1 sewing machine. in combination. stitch-forming mechanism. means for con action. a work-holder comprising upper and lower members. operating means connected with the upper worlr chimping member for opening and closing the work-holder. a plurality of thread-cutting devices mounted upon the upper clamping member. and means acting independently of said operating means for actuating the thrcnd-cntting devices succes' sively in different stitch-forming cycles of a stitching period.

3. In a sewing machine. in combination,

stitch-forming and feeding mechanisms, means for controlling their period of action, a. work-support. a plurality of movable thicad-cuttmg devices disposed above the work-support having raingcs of notion omactioln 85 ports of the 95 upper and lower workriamping 105 stitching 1 10 work-clumping 115 lead of and adapted for engagethrcad of the stitch forming mechanism. means connected with one of said l'lltt'ltttlll lll for timing thc a tion of one of v aid devices in severing said thread. and llllillh for setting the other of said devices in mot ion to serer ttltl thread at another point in its length.

4., In a sewing machine. in comhination. stitch-forming and tcediue mcclmnism means for controlling their period of action. a plurality of thread-cutting devices. mean connected with one of said nu-chanisms t'or tilllillfl the actuation of one of said devices. and means connected with said controlling llltttlb for timing the action of the other f said devices.

5. in a sewing machine. in combination, stitch-forming and feeding mechanisms. means for controlling their period of action. a plurality of threads-Al ce device-x each includin; at reciprocatory tlucad-cutting element. means acting during stitching pc riods for retracting said thread-cutting eh ments from advance cutting position. means connected with one of said mechanisms t'or timing the actuation of one of said devices. and means independent thereof t'or timing the action of the other of said devices.

6. In a sewing machine, in comhination. stitch-forming: and feeding mechanisms, means for controlling their period of action, a plurality of thread-cutting devices each including a reciproeatory thread-cutting element, means acting through one. of said cutting devices for retracting the cutting elc ments of 'hoth from advance cutting position, and mutually independent means for effecting the action of said cutting devices successively.

7. In a sewing machine, in combination, stitch-forming and feeding mechanisms, means for controlling their period of action, a. plurality of thread cutting devices each including a reciprocntory thrcadcutting element, means independent of the feedprodncing elements of the feeding mechanism and said controlling means for retracting said thread-cutting elements from ad- Vance cutting iosition, means connected with one of suit mechanisms for effecting the actuation of one of said devices, and means independent thereof for effecting the action of the other of said devices.

8. In a sewing machine, in combination, stitchdonning, and feeding mechanisms, means for controlling their period of action, a plurality of threiul-cuttiug devices each including a reciprmtatory thread -cutting element, means independtint of said mechanisms and connected with one of said threadcutting elements for effecting the retraction of the latter from advance cutting position, a connection between saidcutting elements for effecting the retraction of the other outbracing the ment with the same tine; element, means connected with one of said mechanisms for efl'ecting, the actuation of one of said devices, and means independent thereof for eti'cctinn' the action of the M ller of said dcriccs.

i ill a scuinp' machine. in comhination,

din-Informing mechanism. means for con trolling its period of action, a work-holder comprising uppcr and lower worleclamping memhcr llltttlh for producing relative feedin; ll|(l\t'llltlll hctwccn the stitch-forming ncchanism and the work-holder, a springactuatcd thread-cutting device mounted upon the upper clamping member, means including a latch for setting, and holding it in position for operation, and means controlled h said relatire l'ccding' movements and timed to act hcl'orc the completion of a stitching! period for tripping said latch to clicct the operation of the thrciul-cutting device,

lit. in a sewing machine, in combination, stitch-t'ormin;, mechanism. a plurality of thrcadwuttine devices each including a spririg-actuated reci irocatonv thread-cutting element, a latch for maintaining onc. oi said tlneada'utting elements in retracted position, a connection between said cutting devices wherehy the retraction of one of said cutting elements effects thc retraction of the. other, retracting means connected with the fii-st-named cutting, element. tripping means for said latch, and means for etiecting the action oi the first'namcd cutting device.

11. In a sewing machine, in combination, stitch-forming mechanism. a work-holder, means for producing; relative feeding movenients between thev stitchlorininp mechanism and the \\0Xkil0lti0t, a plurality of thread-cutting devices mounted upon said work-holder and each including a springactuated reeiprocatonv thread-cutting element, a latch for maintaining one of said thread-cutting elements in retracted position, a, connection between said cutting de vices whereby the retraction of one of said cutting elements'cfi'ects the retraction of the other, retracting means connecttal with the first-named cutting element, tripping means for said latch, and means for cflecting the action ofthe first-named cutting device.

12. In a sewing machine, the combination with stitch-forming mechanism, of a lurality of thread-cutting devices each inc ud ing a springaictuattal cutting element, a latch for retaining each of said cutting elements in retracted position. and independently acting tripping means for said latches whereby said cutting devices are caused to operate in succession.

' 13. In a sewing machine, the combination with successively operating mechanisms ineluding stitch-forming mechanism, of a plurality of thread-cutting devices each including a spring-actuated cutting element, a

latch for rctaining cach of said cutting eleinunts 111 rutractcd POMUOD, and trigplng 1111111115 each connc tcd 111th one of $111 s110- cossivcly acting nn-chaniann whcrehv said ltttt'llcs' 111 c succcwivcly rr-ndured incl ective.

14" in :1 scwing: machine, in combination, .\tit1-h-i'11rn1ing and funding niochanisnis, :1 stop-motion; for controlling their pcriod of action, a phirality of tl11'ca1l-c11tting devices each including :1 1'1 1'i111-11c:1t11ry cutting clelncnt. :111 11111-1'ativc connect i011 hotwvon one of said cutting dcvicc and the fcoding 1111 1-l1:111i-111. and an opcrativc conncction het\\'c1-n :l1111t'l11 1' of said cutting devices and tl11 nt11p-1110ti011.

l3. l1: :1 H(\\l11;I machine. in u11111hinatio11, dlitlhl lil'lltlllg 111c1i1a11is111. a work-holdcr, 1111-:1|1 1111' producing l1l11ti111 fccding 11111111- lncnls la-tnven th1= stitch-iorining 1119 4111- nim and the norklioldcr. :1 tlncad-cntting dwicc niountcd 11111111 -ai1l norloholdvr and r-oniprisingz :1 .\l)llI\;.!:1 l'1i21tL1l cutting ole- 1111-111w 1111 1111 including a latch and :1 trawling v\npport thcrct'or 111111il'i1l1 ditl'vrontiall 11f ai1l rolatitc tram-i111; 11==1\'1-|111-|1t 'wlim' l1 said 1-11tti111 1 11 1111 111; i,- 11 1111111 11, and tripping 1111-11115 for #:llti latch.

11'1. ln :1 scn'ing inavhinc. in waniaination. stitch-Forming nincaaninn. :1 \\'(1l'i{ ili!l(i[1. moansv for producing 1'1-latiw hauling mow-- mcnt-z hutwccn thc ,-'tit1'l1-f111-|11ing' 1111 14111- 11is1n and tl11- woric-holdcr- :1 plurality of tl11ca1l-111tti11g til'vil'vs 11111|1nt01i 11111111 work-holdcr and cach including: a spring actnatod 1-v1-ip1'o1-:11o1 1' tln'tatlanttingi 1-l1-- 1|111'1t. rctracting 1111-11115 for mid cutting clc- :ncnts. lzltl'lit-s for retaining thc cutting 1 h- 11101111 in rctracha'l position and 1111111ntc1l 1'11- spcctivcl) 11111111 and indtpotnlcntly of said worlc-lioldor. and 1110:1111: for Mfl'ttSSlYtl) tripping said latches.

ii. In :1 slowing lmltlilm. in 1'11111l1i1111li011. stitchd'orming muclmnisni. :1 \wrk-lnddor, 111011115 for opening and closing; the $111111. a tension device. 11 tcnsion 1'clc-aso push-pin connected thcrcwith and adaptvd to 1'P111l1-1' the tension (lmicc inctl'octivm :1 tension 1- 3- luase rock-lovur operahlv indcpoxnlcntly ot the work-hohlcr opening and closing 1110:1115 and adapted for dirm't cngagcmcnt with said push-11in, :1 tl11cad-c11tt111g device. and moans 1-1111110ct11d with and actuated by said tension relonso rock-lcvvr for otfccting the action of tho thrcad-011tting device.

19. In :1 sewing mnchimu in conilvination. stitclr't'orining incchanhan, :1 tension device. :1 tension releascr. :1 thread-cutting l1 1'i1-11 comprising a spri11gactnnted cutting 1-11:- ment and a detent for holding it in retracted position, means for setting Said cutting element in retracted position, and means connected with the tension relenser; for dim-ngaging said detont to cans the actuation of said cutting element. V

19. In a sewing machine, in combination,

stitch-forlning mechanism. a thread pull-01f device, a thread-mating device comprising a springactuated cutting element and a do tent for holding it in retracted position, 1111 11115 for Setting said cutting clcmcnt in rvtractcd msition. and 1111 11111; connctod with said pull-11H dcvicc for disengagin said dotcnt to cause the actuation of 511i cuttin" elcmcnt.

2t). l11,:1 sowing: machine. in combination, stitch-forming mtl'lltmlslll, a pull-0t]? device, a tl11'1'a1l-1'11tti11g device Comprising a springactuatcd cutting clclncnt and 11 dvtent for holding it in rial-acted position, means for 30 wtting said cutting clcmcnt in rctri'ictcd'position, tripping means for said detent, and an opviatlvo conncction hvtwoen said tripping 111mm and said p11ll-0fi'. w

1? in a sowing: machine, in combination, stiiclvl'm ming 111ecl1anisn1. :1 tension device, a ivlmiun 1'tlt1t:' (t'.2t pnltofl' device, a threadcntt in; iittit't} comnri ing :1 sprin -act11ated utting vh-ln nt in n-tractml position. means for setting said cutting; clcmcnt in rctractcd position. tripping 1:11 :11 for said elctont connected with thc tcnsion relcaser, and an operative connc tion hotwcen said pull-111i devive and tension roleaser whrrrehy the pull-off device is simultaneously actuated with the tension h-asvr and said tripping means.

in a sewing machine. the combination with stitch-forming mochanism. of a thread cutting device intlnding a reciprocatorv cntting chain-11L, means for rah-acting naiontting' 1 11 1111 111 a latch for retaining said cutting 1411110111: retracted, a common Spring conncctml with said throad-clltting element and said latch for imparting operative movement thvroto. and tripping means for said latch.

231 In a sewing 111110111111. the combination with a \\'111:l1-.-;111111o1't and stitch'forming nichanism. of throad-nipping means, pr1- mary and auxiliary thrvad-cntting elements having: a range of movement intermediate said nipping 1111*11115 111111 thowork-support, and 1111 11111: for actuating said throadarntting clclnt'nts in difl'nrent stitch-forming cycles and for maintaining the nipping means in oporativv cngagomont with the thread throughout a period including said stitchforming cycles.

24. In :1 swing machine. thc combination with Min-Informing nn-vhaniqn, of primary tl1r1-z1d-c11tti11g and nipping 1111 11115. an anxiliaiy thread-cutting clvnmn t having a rangc of amvcnmnt interlncdiate said nip- 1ing moans and the work, moans for act11at- 111g! thc primary thread-cutting and nipping nn-ann and for lnaintaining thc nipping means effective for more than a complete stitch-f11rn1ing cyclo. and 11111111111 for actuat' ing' the angiliary cutting 141 11 1 111 whilc said nipping lllttthS arc cii'cctivc and in :1 stitchand :1 detent for iolding it mechanism, of t forming cycle succeeding that in which the primer cutting means operate.

25. n a sewing machine, the combinatio' with a work-sup ort and stitch-formin mechanism, of tiiread-nippin means, a thread-cutting element movube in a path intermediate the nippinr means and the work-support, a second tn'cad-cutting element movable intermediate said nip )ing means and the path of movement of the iii-stnamed cutting element, means for imparting to said thread-nip ring means and the set end-named three -cutting element operative thread engaging movements at the completion of a stitching period, means for actuatin the first-named cutting element after the initial stitch-forming cycle of the next succeed ing stitching period. and means actin in the last-named stitching eriod and su sequently to the action of the rst-named cutting element for retracting said nipping means and both of said thread-eutting elements. i

26. In a sewing machine, the combination with a work-support, stitch-formin mechanism, and a stop-motion for contro ling the action of the stitch-forming mechanism, of thread-nip ing means, primary and auxiliary threa -cutting elements having a range of movement intermediate said nipping means andjhe work supportai means for imparting operative thread-engaging movements to the nip ing means and the primary thread-cutting e ement at the completion of a stitching period, means for imparting an operative thread-severing movement to the auxiliary thread-cutting element after an initial stitch-forming cycle of the next suc' ceeding stitching period, and means for retracting the nipping means and one of said cuttin elements during the second-named stitching period and thereby dislodging by meansof the said tln-ead-cutting element the section of thread previously held by the nipping means.

27. In a sewing machine, the combination with a worli-su )PUI't and stitclrfbrming mechanism, of tircad-nipping means, primary and auxiliary tln-ead-cutting elements having a range of movement intermediate said ni )ping means and the work-support, means or actuating said thread-cutting elements and the nipping means to sever and 'hold a section of'the stitching thread. means for dislod ing from the nipping, means said section of t read, and means for efl'ccting the removal of said thread-section from proximity to the stitch-forming mechanism.

28. In a sewing machine, the combination with a work-su )port and stitch-forming bread-nipping means primary and auxiliary thread-cutting elements having a range 0 i movement intermediate said ni ping means and the work-support, means or actuating said Gilead-cutting elements and the nipping means to sever and hold a section of the stitching thread, means for dislodgin' from the niiping means said section 0 thread, a. nozzle directed toward the thread-cutting elements, and means for supplying a current of air to said nozzle.

'29. In a sewing machine, the combination with stitelnt'ornnng mechanism, a workhoider, and means for producing feeding movements between said stitch-forming mechanism and work-holder, of thread-nipping means and primary and auxiliary thread-cutting elements mount/ed upon said work-holder, means for imparting to said thread-nipping means and one of the threadcutting elements operative threadengaging movements in one stitclrforming cycle and for imparting to the other threadcidting element an operative movement in a subsequent stitch-fining cycle while the thrciul-nipping means remains in engagement with the'thread, means for imparting rctraetive movements to the thread-nipping means and to both thread-cutting elements in the second-named stitch-forming cycle, a nozzle sustained in fixed relation with the work-holder durin said feeding movements. and means for supplying a current of air to said nozzle.

30. In a. sewing machine, the combination with stitch-forming mechanism, a workholder comprisin a work supportin member and a work-c am )ing member plvotally mounted thereon, an Y means for producing relative feeding movements between said stitch-forming mechanism and work-holder, of thread-nipping means and primary and auxiliary thread-cuttin elements mounted upon said work-clamping member, means for imparting to said thread-nipping means and -to one of the thread-cutting elements operative thread-engaging movements in one stitch-forming cycle and for imparting to the other thread-cutting element an o erative movement in a subsequent stitcht'orming cycle while the thread-hi ping means remains in engagement wit the thread, means for imparting retraetive movements to the thread-nipping means and to both thread-cutting elements in the second-named stitch-forming cycle, a nozzle istaincd upon said work-supporting memher and directed toward the thread-cutting elements, and means for supplying a cur rent of air to said nozzle.

3]. in a sewin machine, the combination with stitch-forming mechanism, a traveling work-holder comprising a work-supporting member and a workclamping member piv otally mounted thereon, and means for imartmg feeding movements to the workiolder, of thread-nipping means and primary and auxiliary thread-cutting elements mounted upon said work-clamping member,

means for im .-arting to said thread-nipping means and to one of the thread-cutting elements operative threadcngaging movements in one stitch-forming cycle and for impart.- ing to the other threinl-cutting clement an operative in u'emont in a subsequent stitchforming cycle while the threadmi iping means remains in engagement witi the thread, n'icans for imparting retractive movements to the thrcad'nipping meanaand to both thread-cutting elements in the seconcl-named stitchdorming cycle, a nozzle sustained upon said work-supporting memher and directed toward the thread-cutting elements. an air-pump mounted upon a fixed part of the machine, and a flexible conncction betwem'i said airqnnnp and said nozzle.

32. In a sewing machine, the combination \rith stitch-forming mechanism, and a worle holder comprising a clamping foot adapted to rest upon the work, of a thread-nipping device sustained by said foot in close proximit to its vo'rkcngaging face, a threadcutting element for severing the thread between said nipping: device and the ork, and an a uxiliar; thread-cutting element movable in a. path intermediate said threadnipping device and the work and substantially in I contact with the latter.

33. In a sewing machine. the combination with stitch-forming mechanisn'i, of a plurality of thread-cutting devices; each including a spring-actuated cutting element. latches for normally restraining said cutting: elements against movement under the action of their respective springs, means: operatively connected with moving parts of said machine for compressing said springs, and

successively acting tripping means for said latches.

34. In a sewing machine, the combination with stitch-forming n'iw-hauism and workfeeding mechanism including a traveling Work-holder and a feed-wheel for impart ing operative movements thereto, of a plurality of thread-cutting devims each including a spring-actuated cutting clement, latches for retaining said cutting elements respectively in retracted position, means connected with said feed-wheel for setting said cutting. elements in'retractcd position in opposition to their respective springs, and successively acting tripping means: for said latches. i

35. In asewiug machine, in combination stitch-forming mechanism. nipping means adapted to grip a thread, a primary threadcuttiug device, an auxiliary thread-cutting device comprising a cutting clement performing movements relatively to said nipping, means, and actuating and controlling IllCflz-d for said nipping means and threadrlitling dmicoa timed to effect the nipping, of said thread and the repeated cutting of lllc sumo. \vhilo subje ted to a single gripping action of the uippin; means.

36. In a mowing machine, in combination, stitch-twining mechanism, a thread-nipping device, a plurality of thread-cutting devices adapted to act upon the same thread and of which one comprises an clement adapted to perform operative threadengaging movements relative to said thread-nipping device, and artuating and controlling means for said thread-nipping and cutting devices timed to actuatitho nim'icr to nip the acedIe-tln-uad and thereafter subject tho nipped in-odle-tln'e-ad to the a tion of tho cutting dciires in succession while the thread re mains. held by tho uippindevice.

37. in a sewing machine. the combination with stitt-h-formi'ng mechanism, of a plurality of that-ad cutting; devices (-ach including a :,-prin,- -at-tuatvd cutting element hav in: a range of action cmlmuing the same thread and llfln'lm'll at a dili'elent distance from tho work than that of the. the tting it-Vi i. and means for operating: said cutting tltfl'ltjts respectively in succession.

218, In a sewing machine, the combination with stitch-forming: mechanism including a rccim-ocating needle. and a work-support, of a nluralit of thrcatlwuttingdevices disp sed above the Work-support and each ineluding a sprin r-acttuitial cutting element havin; a range of action embracing the neediv thread and disposed at a different distance from lllt norlt than that. of the other cutting dcvict'. and means for operating said cutting (ltTlt'OH respectively in succession.

35 In a sowing machine, in combination, 5ili(l\'ffllllllllfldlltllltllllfilll including a recip- I'm-tiling noodle. means for nipping and severing the uet-r'tlo-tlu'cad at the end of a stitching operation, an auxiliary thread-so"- i-ring device. and means for moving said auxiliar threadsevering device across the load of the nipped noodle-threadend while the latter is held nipped to sever the waste cud of ncmlle-tlnead at the upper side of tllt 0ll\' during: the ne$t succeeding stitching onerat ion.

in testin'iony whereof, I have signed my name to this s|)ccificati0l1, iu the presence of two stlllrit'l'lblllg \vit'nesaes.

l", DWARD B. ALLEN.

W i tncswa S'lA-NLEY N. SMITH, llAROLI) C. FAULKNER.

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