US2318843A - Thread-severing device for sewing machines - Google Patents

Description

J. P. ENOS THREAD SEVERING DEVICE FQR SEWING MACHINES Filed Jan. 8,-1941 2 sheets sheet 1 J. P. ENDS THREAD SEVERING DEVICE FOR SEWING MACHINES May 11, 1943.

Filed Jan. 8, 1941.

2 Sheets-Sheet 2 Patented May 11, 1943 THREAD-SEVERING DEVICE FOR SEWING MACHINES John P. Enos, Union, N. J., assignor to The Singer Manufacturing Company, Elizabeth, N. .L, a corporation of New Jersey Application January a, 1941, Serial No. 373,556

- 30 Claims. (Cl. 112-252) This invention relates to thread-severing de-= vices for sewing machines and, more particularly, to thread-severing devices adapted automatically to sever the stitching thread or threads between successively stitched articles.

The present invention comprises an improvement in the thread-severing device forming the subject of the pending U. S. patent application of Thomas A. Anderson, flied Dec. 9, 1939, with Serial No. 308,465, which has resulted in Patent 2,293,236 issued on August 18, 1942.

A primary object of this invention is to provide a sewing machine having variable stitchlength work-feeding mechanism with work-controlled means for severing the stitching thread close to the work with substantial uniformity.

Another object of this invention is to provide a sewing machine with means for varying in substantially the line of seam formation the thread-severing coaction position of complemental thread-severing members in severing the stitching thread close to the work.

More specifically, the invention has for an object to provide for severing the stitching thread uniformly'close to the work in a sewing machine having a thread-severing member movable with a variable stitch-length work-advancing element.

'Ihe present invention also aims to provide work-controlled complemental thread-severing devices which are self-adaptable to inequalities in the thickness of the work, and which devices may be relatively adjusted to meet the conditions incidental to variations in stitch-lengths.

Other and more specific objects of the inven-- tion will be apparent from the following description and claims.

The invention consists in the devices, combinations and arrangements of parts as hereinafter described in connection with the accompanying drawings which illustrate preferred embodiments of the invention and in which:

Fig. 1 is a front end elevation of a portion of a sewing machine containing one form of the improved thread-severing device, the bed-plate of the machine being shown in vertical section. Fig. 2 is an'enlarged side elevation of the presserfoot and theattached work-responsive threadsevering device illustrated in Fig. 1. 'Fig. 3 is a top plan view, partly in section, of the presserfoot and the work-responsive thread-severing device shown in Fig. 2. Fig. 4 is a bottom plan of the presser foot and the work-responsive thread-severing device. Fig. 5 is a rear end elevation of the presser-foot and the work-responsive thread-severing device, with the shank of the pres'ser-foot partly broken away. Fig. 6 is a top plan view of the throat-plate, the feed-dog and a portion of the bed-plate of the sewing machine illustrated in part in Fig. 1. Fig. 'l is an enlarged vertical section, longitudinally of the presser-foot, throat-plate and feed-dog of the machine. Fig. 8 is an enlarged fragmentary view in side elevation of the work-responsive thread-severing device and illustrating the adjustment of the thread-severing element. Fig. 9 is an enlarged fragmentary bottom plan .view of a work-responsive thread-severing device similar to Fig. '4, but with the severing element having a modified cutting edge. Fig. 10 is a side elevation ofa presserfoot having an alternative form of work-responsive thread-severing device associated therewith. Fig. 11 is a rear side elevation of the presserefoot of Fig. 10. Fig. 12 represents a substantially horizontal section of the modified presser-ioot, substantially on the line l2l2 of Fig. 10. Fig. 13 is a top plan view of the throat-plate and feeddog of the machine, including an overlying corner portion of stitched work.

Referring more particularly to Figs. 1 to 8, inclusive, and Fig. 13 of the drawings, which illustrate a preferred embodiment of the invention, the sewing machine has the usual frame including a work-supporting bed-plate l5 and a bracket-arm head l6 overhanging the bed-plate. J ournaled for endwise reciprocation in the bracket-arm head it is a vertically disposed needle-bar I? provided at its lower endwith an eye-pointed needle l8 carrying a needle-thread a.

Complemental to the needle l8 in the formation of lock-stitches is a loop-taker l9 which, in the present case, is in the form of a horizontalaxis rotary hook adapted to cast loops of needlethread a about a mass of under thread b (shown in Fig. 7) contained in a thread-carrier 20 suitably journaled in the loop-taker and. restrained against rotation therewith. The present invention is, however, not limited to any particular form of stitch-forming mechanism.

The work 10 (shown in section in Fig. 7) is intermittently advanced across the upper face of the bed-plate l5 and past the needle l8 by a feed-dog 2| of the drop-feedvtype and having laterally spaced rows 22, 23 and 24 of feeding teeth. The feeddog 2| is secured by screws 25 upon a horizontally disposed feed-bar 26, of which the rearward end is pivotally connected to the upper end of a vertically disposed rocker 21 carried by a feed-advance rock-shaft 28 which may be supported and actuated in any usua1 or suitable manner (not shown) to impart work-advancing movements of variable amplitude to the feed-dog 2|, At its forward end, the feed-bar 26 has a fork 29 operatively connected to a crankarm 30 of a feed-lift rock-shaft 3| which may likewise be supported and actuated in any usual or suitable manner (not shown) it being understood that the present invention is not limited to any particular form of feed-actuating mecha-' nism.

The feed-dog 2| in its operative movements is projected through a throat-plate 32 secured by screws 33 upon the bed-plate l5, said throatplate having a needle-aperture 34 and a plurality of feed- slots 35, 33 and 31, providing clearance for the rows 22, 23 and 24, respectively, of the feed-dog teeth. By referring to Figs. 6 and 13 of the drawings, it will be noted that the left hand row of feed-dog teeth 22 comprises a comparatively wide front section 22' and a relatively narrow rear section 22", the latter section being formed by cutting away one side of the row of teeth rearwardly of the needle and at the needle side of the row of teeth. The throat-plate feed-slot 35 receiving the row of teeth 22 has the rearward portion thereof correspondlngly constricted in, width.

The right hand row of feed-dog teeth 24 is disposed at the side of the throat-plate needleaperture 34 opposite the left hand row 22 and is spaced more widely from said aperture 34 than the front section 22' of the teeth 22, so that the row of teeth 24 and the rear section 22" of the row of teeth 22 are substantially equally spaced from the line of scam formation.

The middle row of teeth 23 of the feed-dog is disposed entirely in rear of the throat-plate needle-aperture 34, and the teeth 23 are widthwise centrally in alinement with the line of seam formation whereby said teeth 23 not only engage in the absence of work. The teeth 23, with the exception of the rear tooth, are preferably narrow in width, so that when the feed-dog 2| drops below the upper face of the work-support in the absence of work, the, concatenated threads are confined against lateral movement by the correspondingly narrow feed-slot 36 of the throatplate through which the teeth 23 operate, whereby the concatenated threads are maintained substantially in the line of seam formation.

The rear tooth 23', of the row of teeth 23. functions primarily as a thread-severing member, said tooth 23' having a horizontally fiattened upper face preferably widened equally at opposite sides of the row of teeth 23 to provide a tooth of substantial width. The upper rear edge 33 of the tooth-23' comprises a sharpened cutting edge formed by hollow grinding the rear end portion 38 of the feed-dog. The cutting edge 38 of the feed-dog may be readily resharpened, when required, by further hollow grinding the rear end of the feed-dog, it being understood that the flattened upper face of the tooth 23' is preferably disposed in the plane containing the upper or work-engaging edges of the teeth 23. While the cutting edge 38 is illustrated in the drawings as extending horizontally normal, to the line of feed, it may be otherwise disposed to extend across the line ofseam formation.

The section 22" of the row of teeth 22 is preferably cut away at the rearward end thereof, so that the teeth of said section 22" terminate well in advance of the cutting tooth 23' of the feed-dog, for a purpose hereinafter explained. The feed-slot 36 of the throat-plate is widened to provide a slot-extension 36' affording the necessary clearance for the cutting tooth 23' of the feed-dog. The slot-extension 36' is elongated a substantial distance rearwardly of the feed-dog, thereby providing an opening in the throat-plate through which thread-clippings may drop. I p

.Opposedto the feed-dog 2| is a work-engaging sole-plate 40 of a presser-foot having a shank 4| detachably secured by a screw 42 to the lower end of a vertically-disposed presser-bar 43 journaled for endwise movement in the framehead l6 and spring-depressed in any usual or suitable manner. The sole-plate 40 is provided intermediate the ends thereof with laterally scaced and upstanding ears 44 disposed at opposlte sides of the lower end of the presserioot shank 4| to which the ears 44 are pivotally attached by a pivot-pin 45 disposed transverse to the line of seam formation. The presser-foot sole-plate 40 has the usual thread-clearance slot 46 extending rearwardly from the upturned toe of the sole-piece to terminate in a needle-aperture 41 in front of the pivotal axis of the soleplate. The heel of the sole-plate 40 is rigidly provided medianly of the width thereof with a relatively 1 narrow extension-piece 48 opposed to the teeth I 23 of the feed-dog. The under face of the extension-piece 48 is substantially flush with the work-engaging face of the sole-plate 40 and the 3 upper face of said extension-piece is preferably beveled downwardly toward its rearward end. Rearwardly of its pivotal axis and in advance of the extension-piece 4B, the upper face of the sole-plate 4B is suitably recessed to receive a spring 49 interposed between the heel of the sole-plate and the recessed lower end of the presser-foot shank 4|. The spring 48 therefore functions yieldingly to depress the heel of the sole-plate 40.

Rearwardly of the sole-plate pivot-pin 45, the presser-foot shank is provided with a. transverse aperture 50 to loosely receive a pivot-pin 5| extending transversely of the line of scam formation. Attached to the pivot-pin 5| at opposite sides of "the presser-foot shank 4| are the laterally spaced ears 52 extending forwardly from the upper portion of a work-responsive cutter-block carrier 53; The carrier 53 is longitudinally recessed to provide a downwardly open T-shaped guideway 54. Slidably and replaceably disposed in the guideway 54, for adjustment toward and from the path of needle-reciprocation. is a thread-severing member complemental to the lower member 23' and comprising a cutter-block 55 having in one side face thereof a substantially vertical slot 56. Extending into the cutter-block slot 56 is a crank-pin 51 comprising an eccentrically reduced portion of a horizontally disposed adjusting stud 58 extending crosswise'of the line of seam formation. The stud 53 is iournaled for turning adjustment in an aperture 59 provided in the carrier 53 and is secured in set position by a screw threaded into the carrier 53. The set position of the cutter-block may be indicated by suitable graduations marked upon the carrier and the head of the stud 58.

The carrier 53 and the cutter-block 55 are preferably cut away at the under side thereof so that the under face 6| at the heel of the carrier and the under face 62 at the heel of the cutterextending from the finishing end of the work to block are rearwardly beveled upwardly. ,The beveled face 82 of the cutter-block terminates at its forward end in a cutting edge 63 which extends crosswise of the line of seam formation and is formed by stepping the under face of the cutter-block: said cutting edge 83 being substantially flush with the work-engaging face of the carrier 53 in advance thereof. The front portion of the cutter-block 55 also has an inclined face 84 formed by beveling said, block downwardly toward the cutting edge 53, whereby the guideway slot 54 of the carrier 53 provides a clearance recess for the sole-plate extension-piece "-8 of the presser-foot. As provision is thus made for the free end of the soleplate extension-piece to terminate directly in front of and close to the cutting edge 63 of the cutter-block, the threadchain is fed with certainty to said cutting edge by the feed-dog 2|.

The cutter-block carrier 53 has a rearwardly projecting lug 65 formed in its upper face with a recess 85 providing a seat for a coil-springST. The spring Bl embraces a stabilizing post 58 depending from a collar 59 secured by a screw 10 for vertical adjustment upon the presser-bar, said spring reacting against the collar 69yieldingly to depress the cutter-block carrier 53 toward the throat-plate 32.

The aperture 50 formed in the presser-foot shank to receive the pivot-pin 5| is preferably elongated to provide a floating pivotal support for and thereby to accommodate universal movements of the cutter-block carrier 53 responsively to variations in the thicknessof the work. To this end, the aperture 55 is preferably formed as an arcuate slot having its center of curvature in the cutting edge 53 of the cutter-block in substantially a median position of adjustment of the cutter-block. By means of this arrangement, the cutting edge 33 is maintained in the requisite thread-chain severing position, regardless of work-responsive movements of the cutter-block carrier 53 at a time when the edge of the work is introduced under said carrier.

Inasmuch as the cutting edge 53 of the cutterblock 53 is disposed in substantially the plane of the work-engaging face of the carrier 53 it is evident that, so long as the work-engaging face of the carrier 53 in advance and adjacent said cutting edge 63 is in engagement with work passing thereunder, thecutting-edge 63 will be held out of severing engagement by-the cutting edge 38 of the feed-dog 2!. As previously described, the under face 6! of the carrier 53 and also the under face 52 of the cutter-block 55 are inclined upwardly rearwardly of the cutting-edge $3. Consequently, when the finishing end of the stitched work passes beyond the cutting-edge 53, the cutter-block carrier 53 will be depressed by the spring El into engagement with the throat-plate 32, thereby increasing a normal rearwardly downward inclination of the work-engaging face of the carrier 53 in advance of the cutting-edge 63.

When thefeed-dog 2i rises, the cutting edge 38 thereof is disposed directly below the presserfoot extension-piece t8 and in advance'of the complemental cutt ng edge 53. The presser-foot 40, 3| yields vertically to the rising movement of the feed-dog 2i and relatively to the cutter-block carrier 53, When the work has been advanced past the heel of the presser-foot, the teeth 23 of the feed-dog engage and feed the stitching thread the throat-plate needle-aperture '34. As the front under face of the cutter-block carrier 53 is inclined to the horizontal plane of the throatplate 32, said carrier 53 yields slightly vertically to the thread-feeding movement of the feed-dog but, nevertheless, remains at an inclination to said sole-plate. The rear or thread-cutting tooth 23 of the feed-dog engages the cutting-edge 53 of the work-responsive member and shears the threads close to the work. The feeding of the threads to the cutting edge 63 is preferably facilitated by slightly grooving the teeth 23 to partly receive the threads, thereby guiding the threads. The grooving of 'the feed-dog teeth also minimizes mutilating the stitching threads during a normal sewing operation. The presserfoot follows the feed-dog in its subsequent downward movement, thereby depressing the stitching threads into the narrow throat-plate feed-slot 36 and confining said threads against random lateral movement.

The feeding and severing of the stitching threads continues to occur during each complete cycle of movement of the feed-dog '2i until the beginning end of a succeeding piece of work engages and lifts the cutter-block carrier 53, so that the cutting-edge 53 of the cutter-block is held spaced by the work from engagement by the cutting-edge 33 of the feed-dog. Consequently, the stitching threads are automatically severed close to the beginning end of the work, as well as to the finishing end thereof. As the workresponsive cutter-member 55 is adjustable in the line of seam-formation, toward and from the path of needlereciprocation, the thread-severing coaction position of the complemental cutter-members may be varied to correspond with variations in the amplitude of the work-advancing movements imparted to the feed-dog 2|.

When the beginning and of the work initially passes under the presser-foot, the pivoted soleplate 40 is tilted to leave the heel portion thereof alone depressed. The sole-plate extensionpiece 48 thereby remains in engagement with the stitching threads until the beginning end of the work. also lifts said extension-piece. As the extension-piece 48 of the presser-foot terminates in proximity to the cutting-edge 63 of the workresponsive member, it is evident that the stitching threads are fed by the opposed feed-dog 2| and presser-foot directly to the cutting-edge 63. The extension-piece d8 of the presser-foot coacts, of course, with the feed-dog teeth 23 in also advancing the work.

The set position of the cutter-block upon its carrier 53 is preferably such that the feeddog 2| completes its work-advancing movement directly after the cutting edge 38 of the feed-dog passes the cutting-edge 63 of the cutter-block 55. By having the feed-dog 2| perform the major portion of its work feeding movement in advance of the upper cutting edge 63, the thread-chain is fed with greater certainty to the cutting edge 63 for severance by the feed-dog cutting edge 38, in the absence of work. The termination of the work-advancing movement of the feed-dog 2| close to its thread-severing position also eliminates puckering effects in the work, because the back-feeding resultant pivotal movements of the cutter-block 55 are thereby reduced to an ineffective minimum.

As illustrated in Figs. 6 and 13 of the drawings, and as previously described, the section 22" w, as illustrated in Fig. 13, the finishing end of the work is inclined to the line of feed. By cutting away the rearward portion of the teeth 22" of the feed-dog, the work-clearance gap thus pro.- vided permits the cutter-block carrier 53 to descend as soon as the finishing end of the work has passed the thread-cutting tooth 23', thus effecting severing of the stitching threads close to the finishing end of the work. When beginning to attach a comer-label i, the edge of the work an is oppositely inclined to the line of seam formation. While in thiscase the work 10 adjacent the label I may initially slightly lift the work-responsive member, before the edge of the label itself has reached the cutting-edge 83 of the work-responsive member, the feed-dog rises high- 25 er above the work-support than the thickness of the work w. Consequently, the work-clearance gap provided by shortening the row of the feeddog teeth permits the cutting edge of the feeddog 2i to continue to sever the thread-chain up to the time that the needle begins to penetrate the label.

In the modification shown in Fig. 9, of the drawings, the cutting-edge 63 of the cutter-block 55 is formed horizontally arcuate, thereby illustrating that the cutting-edge of the work-responsive member may be shaped otherwise than straight to meet requirements.

A modification of the thread-severing device hereinbefore described as complemental to the 4 feed-dog 2| is illustrated in Figs. 10 to 12, inclusive, of the drawings. In its modified form, the presser-foot has the usual shank 12 attached by a screw 13 to a presser-bar H. A work-enpivotally into engagement with the throat-plate 32'.

The carrier 88 is formed medianly of the width thereof with a rearwardly and downwardly open slot 85. Disposed in the slot 85 of the carrier is a polygonal cutter-block 86 supported centrally for turning adjustment upon a pin 81 lengthwise extending transversely of the line of seam formation through alined apertures in the carrier 88. The peripheral faces of the cutter-block 86 are each shouldered to provide the block with a plurality of cutting- edges 88, 89, 98 and SI which are selectively complemental to the cutting-edge 38 of the feed-dog 2! in automatically severing the stitching threads in the absence of work between the complemental cutting elements.

By turning the cutter-block 86 about its supporting pin 81, any one of the several cuttingedges thereof may be selectively opposed to the cutting-edge 38 of the feed-dog, the cutter-block being releasably secured in set position by means of a lockingscrew 82 threaded into the cutterblock carrier 88 and having the reduced end thereof adapted to enter any one of a plurality of suitably located apertures 83 provided in the cutter-block 86.

The several cutting edges 88, 89, 88 and Si when respectively disposed in effective position are spaced at different distances. from the throat-plate needle-aperture 34. The described arrangement therefore provides for relative adjustment of the complemental thread-severing elements to accommodate selected variations in the amplitude of work-advancing movement of the feed-dog 2|.

When disposed in effective position, each of the cutting edges of the cutter-block 88 is substantially fiush with the lower or work-engaging face 83 of the cutter-block carrier 88.

. much as said cutting edges are formed by stepgaging sole-plate 15 is pivotally attached to the presser-foot shank I2 by a pivot-pin 16 extending transversely of the line of seam formation and disposed rearwardly of a needle-aperture 11 in said sole-plate. The heel of the sole-plate 15 is cut away in substantial vertical alinement with the lower rear face of the presser-foot shank and a spring 18 is interposed between the heel of the sole-plate 15 and the shank 12 of the presserfoot.

Embracing the flattened opposite sides of the presser-foot shank 12 above the sole-plate pivotpin I6 are laterally spaced ears 19 extending forwardly from a work-responsive cutter-block carrier 88. One of the ears '19 is apertured transversely of the line of seam formation to receive 60 a pivot-pin 8! having an eccentric portion thereof secured in an aperture in the presser-foot shank I2 by a set-screw 82. The other ear 19 functions as a carrier guide. By turning adjustment of the pivot-pin 8|, the pivotal axis of 6 the cutter-block carrier 88 may be raised and lowered, thereby varying the angle of inclination of the under or work-engaging face 83 of the carrier 88 with respect to the horizontal plane of the throat plate 32. The upper face of the carrier-88 is recessed to provide a seat for a spring 84 interposed between the carrier 88 and the lower end or the presser-bar 14, said spring ping the peripheral faces of the cutter-block, the portion of the lower face of the cutter-block 88 in advance of the effective cutting-edge is disposed slightly above the lower face 83 of the carrier 88 thereby forming a short thread-clearance recess in the carrier-face 83 in front of said cutting-edge. In the absence of work under the carrier 88, the cutting-edge 38 of the feed-dog 2| *severs the threads by shearing coaction with the effectively positioned cutting-edge of the block 85, in the same manner as hereinbefore described in connection with the form of construction illustrated in Figs. 1 to 8 of the drawings.

Havingthus set forth the nature of the invention, what I claim herein is:

1. In a sewing machine, a thread-severing device comprising a primary thread-severing member having effective thread-severing movements of variable amplitude in the direction of move ment of stitched work through the machine, means for actuating said member, a complemental work-responsive thread-severing member disposed in the absence of work for thread-severing 5 coaction with said primary thread-severing member at substantially the completion of the thread-severing movements of said primary member, and means providing for varying the thread-severing coaction position of said mem- 0 bars lengthwise of the line of scam formation in functioning yieldingly to depress the carrier 88 substantial accordance with variations in the amplitude of movement of said primary threadsevering member.

2. In a sewing machine, a reciprocatory needie, a thread-severing device comprising a pri- Inasmary thread-severing member having eifective thread-severing movements of variable amplitude in the direction movement 0! stitched work through the machine, means for actuating said member, a complemental work-responsive thread-severing mcmber disposed-in the absence of work for thread-severing engagement by said primary thread-severing member rearwardly oi the path of needle-reciprocation and at substantially the completion of the thread-severing movements of said primary member, and means providing for adjustment of said work-responsive thread-severing element lengthwise of the line of seam formation for varying the threadsevering coaction positionof said members in substantial accordance with variations in the amplitude of movement of said primary threadsevering member.

3. In a, sewing machine, stitch-forming mechanism including a reciprocatory needle, workfeeding mechanism including a feed-dog having work-advancing movements of variable amplitude, a primary thread-severing member carried by said feed-dog, a complemental work-responsive thread-severing member disposed in the absence of work for thread-severing engagement by said primary thread-severing member rearwardly of the path of needle-reciprocation and at substantially the completion of the work-advancing movements of said feed-dog, andmeans providing for varying the thread-severing engagement position of said members lengthwise or the line of seam formation in substantial accordance with variations in the amplitude of the work-advancing movements of said feed-dog.

4. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, a feeddog having work-advancing movements of variable amplitude, a primary thread-severing member carried by said feed-dog at one side of the work, a complemental work-responsive thread-severing member inefiectively disposed at the opposite side of the work rearwardly of the path of needle-reciprocation, said work-responsive member in the absence of work being disposed for thread-severing engagement by said primary thread-severing member at substantially the completion of the work-advancing movements of said feed-dog, and supporting means providing for adjustment of said work-responsive member in the line of seam formation toward and from the path of needle-reciprocation in substantial accordance with variations in the amplitude of the work-advancing movements of said feed-dog.

5. In a sewing machine, a Work-support, stitch-forming mechanism including a reciprocatory needle, a work-responsive carrier disposed rearwardly of the path of needle-reciprocation for movement toward and from said work-support, a cutter-member adjustably supported by said carrier, means for securing said cuttermember in set position upon said carrier, a thread-severing member having a path of movement for coaction with said cutter-member in severing the stitching threads between successively stitched work-articles, and means for actuating said thread-severing member.

6. In a sewing machine, a work-support, stitch-forming mechanism including a reciprocatory needle, a work-responsive carrier disposed rearwardly of the path of needle-reciprocation for movement toward and from said work-support, said carrier being provided with a guidement which consists in the way lengthwise extending in the line of seam formation, a cutter-member slidably disposed in said guideway, means for securing said cuttermember in set position upon said carrier, a

thread-severing member having a path of movement for coaction with said cutter-member in severing the stitching threads between successively stitched work-articles, and means for actuating said thread-severing member.

7. In a sewing machine, a work-support, stitch-forming mechanism including a reciprocatory needle, a work-responsive carrier disposed rearwardly of the path. of needle-reciprocation for movement toward and from said work-support, a cutter-member slidably supported by said carrier for adjustment toward and from the path of needle-reciprocation, means for effecting minute adjustment of said cutter-member into diiferent set positions upon said carrier, a threadsevering member having a path of movement for coaction with said cutter-member in severing the stitching threads between successively stitched work-articles, and means for actuating said thread-severing member.

8. In a sewing machine, a work-support, stitch-forming mechanism including a recipro-' catory needle, 9, work-responsive carrier disposed rearwardly of the path of needle-reciprocation for movement toward and from said work-support, a cutter-member slidably supported by said carrier for movement toward and from the path of needle-reciprocation, saidcutter-member being provided with a slot lengthwise substantially normal to said work-support, an adjusting stud journa led in said carrier and having an eccentric portion thereof disposed in said slot, means for securing said stud in adjusted position, a threadsevering member having a path of movement for coaction with said cutter-member in severing the stitching threads between successively stitched work-articles, and means for actuating said thread-severing member.

9. In a sewing machine having stitch-forming mechanism including a reciprocatory needle, work-feeding means, and a thread-severing member having a path of movement for severing the stitching thread between successively stitched work-articles, the improvement which consists in the provision rearwardly of the path of needlereciprocation of a work-responsive carrier, supporting means providing for work-responsive movements of said carrier in relatively transverse directions, and a cutter-member disposed upon said carrier for thread-severing coaction with said thread-severing member.

10. In a sewing machinehaving stitch-forming mechanism including a reciprocatory needle, work-feeding means, and a thread-severing member having a path of movement for severing the stitching thread between successively stitched work-articles, the improvement which consists in the provision rearwardly of the path of needlereciprocation of a work-responsive carrier, 2. floating pivotal support for said carrier, and a cutter-member disposed upon said carrier for thread-severing coaction with said thread-severing member.

11. In a sewing machine having stitch-forming mechanism including a reciprocatory needle, work-feeding means including a feed-dog, and a thread-severing member having a 'path of movement for severing the stitching thread between successively stitched work-articles, the improveprovision rearwardly of the path of needle-reciprocation'of a workresponsive carrier opposed to said feed-dog, supporting means providing for universal yielding work-responsive movements of'said carrier, and a cutter-member disposed upon said carrier for thread-severing coaction with said thread-severing member. I

12. In a sewing machine having stitch-forming mechanism including a reciprocatory needle, work-feeding means including a feed-dog, a pressed-foot yieidingly opposed to said feed-dog, and a thread-severing member having a path of movement for severing the stitching thread between successively stitched work-articles, the improvement which consists in the provision of a work-responsive carrier disposed rearwardly of the path of needle-reciprocation, a floating pivotal connection between said presser-foot and carrier providing for universally yielding workresponsive movements of said carrier, and a cutter-member disposed upon said carrier for thread-severing coaction with said thread-severing member. r

13. In a sewing machine having stitch-forming mechanism including a reciprocatory needle,

work-feeding means, and a thread-severing member having a path of movement for severing the stitching thread between successively stitched work-articles, the improvement which consists in the provision rearwardly of the path of needlereciprocation of a work-responsive carrier, a cutter-member provided with a cutting edge and supported upon said carrier for adjustment toward and from the path of needle-reciprocation, a pivotal support for said carrier including a pivot-axis movable laterally in an arcuate path about said cutting edge when the cutting-edge is disposed in substantially a median position of adjustment of said cutter-member.

14. In a sewing machine having stitch-forming mechanism including a reciprocatory needle, work-feeding means, a primary thread-severing member, and a complemental work-responsive thread-severing member havinga cutting edge spaced rearwardly from the path of needle-reciprocation for engagement by said primary severing member in severing the stitching thread between successively stitched work-articles, the improvement which consists in the provision of means for supporting said complemental severing member for universally yielding work-respontive movements in a substantially constant spaced relation of said cutting edge from the path of needle-reciprocation.

15. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, workfeeding mechanism including a feed-dog having a row of feeding teeth rearwardly of the path of needle-reciprocation and in alinement with the line of seam formation, a presser-foot yieldingly opposed to said feed-dog and including a work-engaging sole-plate pivotally supported for movement about an axis transverse to the line of seam formation, the heel of said soleplate having a relatively narrow extension-piece opposed to said row of feed-dog teeth, and means for severing the stitching threads between successively stitched work-articles including com plemental thread-severing members relatively actuated for thread-severing coaction rearwardly of and in proximity to said extension-piece of the presser-foot sole-plate.

16. In a sewing machine, a work-support, stitch-forming mechanism including a reciprocatory needle, work-feeding means including a rearwardly of the path of needle-reciprocation in the line of seam formation, a presser-foot having a sole-plate opposed to said feed-dog, said sole-plate having the heel thereof provided with a relatively narrow and rearwardly extending piece opposed to said row of feeding teeth. a work-responsive member opposed to said worksupport rearwardly of said presser-foot and provided in its forward end with a clearance recess for the extension-piece of said sole-plate, said work-responsive member being also provided with a thread-severing edge disposed rearwardly of said extension-piece, a thread-severing member having a path of movement for coaction with said cutting-edge in the severing of the stitching thread between successively stitched work-articles, and means for actuating said severing member.

17. In a sewing machine, a work-support. stitch-forming mechanism including a reciprocatory needle, work-feeding means including a feed-dog, a presser-foot opposed to said feeddog and having the heel thereof provided in the line of seam formation with an extension-piece, a work-responsive thread-severing member having a work-engaging face opposed to said worksupport and provided with a clearance recess for said extension-piece, said work-responsive member having a cutting-edge disposed substantially flush with its work-engaging face and rearwardly in proximity to said extension-piece, a threadsevering member having a path of movement for coaction with said cutting-edge in the severing of the stitching thread between successively stitched work-articles, and means for actuating said severing member.

18. In a sewing machine, a work-support, stitch-forming mechanism including a reciprocatory needle, work-feeding mechanism including' a feed-dog, a work-responsive member yieldingly opposed to said work-support rearwardly of the path of needle-reciprocation, said workresponsive member being provided with a thread-cutting edge substantially flush with the work-engaging face of said member; and said work-responsive member having the face thereof opposed to said work-support inclined away from said work-support rearwardly from substantially said cutting-edge, a thread-severing member having a path of movement for coaction with said cutting-edge in the severing of the stitching thread between successively stitched workarticles, and means for actuating said threadsevering member.

19, In a sewing machine, a work-support, stitch-forming mechanism including a reciprocatcry needle, work-feeding mechanism including a feed-dog, a work-responsive member having a face thereof yieldingly opposed to said work-support rearwardly of the path of needlereciprocation and provided with a cutting edge, a presser-foot opposed to, said ,feed-dog having the heel thereof extending in the line of scam formation rearwardly into proximity to said cutting-edge between said work-responsive member and said work-support, a thread-severing member having a path of movement for coaction with said cutting-edge in the severing of the stitching thread between successively stitched workarticles. and means for actuating said threadsevering member.

20. In a sewing machine, a work-support. stitch-forming mechanism including a reciprocatory needle, work-feeding mechanism includfeed-dog having a row of feeding teeth disposed ing a feed-dog, a work-responsive member having the face thereof opposed to said work-support provided with a cutting-edge extending across the line of scam formaton, the workopposed face of said member in advance of said cutting-edge being forwardly inclined upwardly, a presser-foot opposed to said feed-dog in advance of said cutting-edge and having a downwardly beveled heel portion thereof extending into proximity to said cutting-edge between the upwardly inclined face of said work-responsive member and said work-support, a severing member having a path of movement for thread-severing coaction with said cutting-edge in the absence of work between said severing member and cutting-edge, and means for actuating said severing member.

21. In a sewing machine, a work-support,

stitch-forming mechm including a reciprocatory needle, work-feeding mechanism including a feed-dog having a plurality of rows of work-,

engaging teeth operating through said worksupport, one of said rows of teeth being provided wit a thread-severing edge disposed rearwardly of e path of needle-reciprocation and in alinement with the line of seam formation, and an adjacent row of said teeth terminating at its rearward end in advance of said thread-severing edge, and a work-responsive member yieldingly opposed to said Work-support and having a cutting-edge disposed for thread-severing engagement by said thread-severing edge of the feeddog in the absence of work therebetween.

22. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, a worksupporting throat-plate having a needle-aperture,

and a feed-slot disposed rearwardly of said needle-aperture in alinement with the line of seam formation, said feed-slot having connected relatively narrow front and wide rear portions, workfeeding mechanism including a feed-dog having a row of work-engaging teeth corresponding in width to the narrow portion of said feed-slot, said row of teeth terminating at its rearward end in a relatively wide thread-severing member operating through the wider portion of said feed slot, and a work-responsive member yieldingly opposed to said work-support and having a cutting-edge disposed for thread-severing engagement by said thread-severing member in the absence of work therebetween.

23. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, a worksupport, work-feeding mechanism including a feed-dog operating through said work-support and having a row of work-engaging teeth extending in the line of scam formation rearwardly of the path of needle-reciprocation, said row of teeth terminating at its rearward end in a thread-severing member having a. cutting-edge extending crosswise of the line of scam formation, said cutting-edge having a length in excess of the width of said row of teeth, a presser-foot opposed to said feed-dog, and a work-responsive member disposed at the presser-foot side of and yieldingly opposed to said work-support, said work-responsive member having a cutting-edge disposed for thread-severing engagement by said thread-severing member in the absence of work between said members.

24. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, a worksupport, work-feeding mechanism including a feed-dog operating through said work-support for engagement with one face of the work, said mation and rearwardly of the path of needlereciprocation with a tooth having a flattened work-eng ging face and a hollow ground rear ing member, and a complemental work-responfeed-dog being provided in the line of seam forsive thread-severing member yieldingly opposed to said work-support rearwardly of the path of needle-reciprocation and in the line of scam formation, the improvement which consists in the provision upon said work-responsive threadsevering member of a plurality of cutting-edges, and means for selectively positioning said workresponsive member with any one of said cuttingedges disposed for thread-severing engagement by said primary thread-severing member in the absence of work between said members, said outting-edges being respectively spaced differently from the path of needle-reciprocation in the operative positions of said cutting-edges.

26. In a sewing machine having a work-support, stitch-forming mechanism including a reciprocatory needle, a primary thread-severing member having a path of movement for severing the stitching thread between successively stitched articles, means for actuating said thread-severing member, and a complemental work-responsive thread-severing member yi'eldingly opposed to said work-support rearwardly of the path of needle-reciprocation and in the line of scam formation, the improvement which consists in the provision upon the periphery of said work-responsive thread-severing member of a plurality of cutting-edges, supporting means providing for turning said work-responsive thread-severing memberfor selectively positioning any one of said cutting-edges for thread-severing engagement by said primary thread-severing member in the absence of work between said members, said outting-edges in the operative positions thereof being respectively spaced differently from the path of needle-reciprocation;

27. In a sewing machine, a work-support, stitch-forming mechanism including a reciprocatory needle, a primary thread-severing member having a path of movement for severing the. stitching thread between successively stitched work-articles, means for actuating said threadsevering member, a work-responsive member yieldingly opposed to said work-support rearwardly of the path of needle-reciprocation and provided with a slot open toward said work-support, a cutter-member journaled for turning adjustment in the slot of said carrier, a plurality of cutting-edges provided upon said cutter-member peripherally thereof and equally spaced from the turning-axis of said cutter-member, means for securing said cutter-member in set positions upon said carrier with. said cutting-edges extending across the lineof seam formation and selectively disposed for engagement by said primary threadsevering member in the absence of work between said members, said cutting-edges in the operative positions thereof being respectively spaced difi'erently from the path 01' needle-reciprocation.

28. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, workfeeding means, a thread-severing member having a path of movement at one side of the work and adapted in the absence of work to sever the stitching thread between successively stitched work-articles, a complemental work-responsive thread-severing member disposed at the opposite side or the work rearwardly of the path of needlereciprocation and in the line of seam formation, a pivotal support for said work-responsive threadsevering member, and means providing for ad- Justment of the pivotal-axis of said work-responsive member into different set positions thereof.

29. In a sewing machine, stitch-forming mech anism including a reciprocatory needle, workieeding means including a feed-dog, a presserfoot opposed to said teed-dog, a thread-severing member having a path of movement for severing the stitching thread between successively stitched articles, a complemental work-responsive threadsevering member having a cutting edge extending across the line oi seam formation, and means comprising an eccentric iulcrum-stnd for pivotally connecting said work-responsive member to said presser-foot. 4

30. In a sewing machinehaving. a work-support, stitch-forming mechanism including a reciprocatory needle, world-feeding mechanism including a teed-dog operating through said worksupport, said teed-dog being provided in the line of seam formation with a thread-severing edge disposed rearwa'rdly or the path 0! needle-reciprocation, and a work-responsive member yieldingly opposed to said work-support and feeddog, said work-responsive member having its work-engaging face provided with a thread-cutting edge, the improvement which consists in the provision between said work-responsive member and said teed-dog of a work-clearance gap rearwardly of said needle and at one side in advance of the thread-severing edge of said feed-dog;

JOHN P. ENDS.

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