US1893577A - Sewing machine for joining fabrics - Google Patents

Description

4 Sheets-Sheet 1 .Fan. 10, 1933. F. M. QARD SEWING MACHINE FOR JOINING FABRICS Filed May 28, 1930 4 $heets-Sheet 2 Filed May 28, 1930 0 m J I 6 z F 9 1? 0 M 9 m r a. $1 15 1 E4 w HM 6. I 17 M B Eim 1 ,fl lu 2 U15 ?1 U 4 mm, H 7 7 m. 6 5 J mm m 5 1 5 y 1... 1 III I? 1 I W/ a Jan. 19, 1933.

WAMM

Jan. 10, 1933. F. M. CARD SEWING MACHINE FOR JOINING FABRICS Filed May 28, 1930 4 Sheets-Sheet 3 gwumtoz fiedera'e 1Z1. Cara? Wimw Jan. 10, 1933. F. M. CARD SEWING MACHINE FOR JOINING FABRICS Filed May 28, 1930 4 Sheets-Sheet 4 [If 44 I14 116 $5- 11 Patented Jan. 10, 1933 FEEDER-IO MI. CARD, OF BBIDGEPORT, COIINECTECUT, ASSIGNOB Q3? FELZZABET'E, EYE-W MANUFACTURER CG'MPD NY, NEW JERSEY SE'WIIIG- IEAGHEINE F03 Application filed I-Eay 28,

This invention relates to improvements in sewing machines and has for its primary object to provide a machine capable of eiiir ciently joining materials, particularly rayon and knit-goods materials, by a stitched seam free from the bulkiness which is a characteristic of the butt-seams produced by sewing machines employed commercially for buttseam joining of materials.

The foregoing and other objects and vantages in view, together with means whereby the same may be carried into effect, will best be understood from the following de- 1: scription of a preferred embodiment of the invention illustrated in the accompanying drawings, in which:

Fig. 1 is a longitudinal section, partly in front elevation, of the sewing i achine. Fig.

2 is a sectional view sub tant'iaily on the line 2-2 of Fig. 1. Fig. 3 18 a front end elevation, partly in section, the sewing machine with the upper portion 0 bracket-arm omitted. Fig. i is a vies, the line H of Fig. 8. Fig.

'-' side elevation, partly in section, of the press er-foot of the machine, including a sectional view of the throat-plate and feed-dogs. 6 is a top plan view of the throat-plate. Fig.

m 7 is a bottom plan view of the machine bedplate. Fig. 8 is a sectional view of the bracket-arm supporting base, substantially, on the line 88 of Fig. 1. Fig. 9 is a detail View in elevation of the primary feed-lever actum ating crank. Fig. 10 is a rear side elevation,

i partly in section, of the. feed-levers. Fig. 11 is a rear side elev of the presser-foot and trimming mechanism. 2 epresents 1 4. JUN A perspective views partly in section, of the presser-foot and the supportuig bracket thereof, one of the foot-plates in dottec lines. 13 is t of the presser-foot work-engao'l omitting the guard blocks and the au iliary foot. Fi' represents perspective views of the feedand their carriers. is a sectional view of the machine bracket-arm, substantially on the l'n 15 of 1.

deferring to the drawings, tee sewing machine is shown as having a frame comprising a bed-plate 1 from one end of which rises a TO THE SINGER JERSM.., A CORPORATION OF L'a'ZINING FABRICS ieee. Serial no. 456,280.

tubular, supporting base 2 for the standard 3 of a tubular bracket-arm 4, which overhangs the bed-plate 1 and terminates in a head 5. Rising from the bed-plate 1, below the bracket-arm head 5, is a tubular worksupporting post 6 of which the front end comprises swing-out closure-plate 7 pivotally connected by a hinge 8 to the base-flange 9 of the post 6. Suitably secured upon the pper end of the post 6 is a throat-plate 10, having a plurality of parallel feed-dog slots, as 11 and 12, and a transverse needle-slot 13. As illustrated more particularly in Figs. 5 and 6 of the drawings, the rear wall of the needle-slot 18 is partly cut away to provide a recess 14 in the upper face of the throatplate inclined downwardly toward said slot 13, said recess 14 affording a clearance for a chainingbfi finger 15 of which the underside is inclined upwardly toward its free end and which finger extends across the needle-slot 13 to overlie the recess 1% in spaced relation thereto, with the upper face of said finger substant ally flush with the upper surface of the throat-plate. The chaining-off finger 15 is in the present case formed integral with a ridged fabric-margin supporting member 16 whose crest 17 is disposed centrally of and parallel with the line of seam formation and terminates in advance of the needle-slot 13 in a downwardly inclined surface 18 merging into the upper face of the chaining-off finger. The member 16 is removably disposed in a recess 19 formed in the upper face of the throat-plate between the front feed-dog slots 11 and 12', said member 16 being secured to the throat-plate by screws, as 20.

Journaled for rotation in suitable bearings provided in the braclretarm 41 is a main actuating shaft 21, carrying at its outer end a driving pulley 22 and at its opposite end a crank-disk 23. This crank-dish serves to actuate in the usual manner a link 24 operatively connected with a vertically disposed needlebar 25 journaled for endwise reciprocation in alined bearing apertures provided in a swinging frame 26. The frame 26 is suspended from a fulcrum-pin 27 to swing about an axis transverse to the axis of rotation of the main-shaft 21 and derives its vibratory movements about the fulcrum-pin 27 from actuating mechanism constructed substantially in accordance with the disclosure in the U. S. patent to C. F. Gray, No. 1,020,089, Mar. 12, 1912. In general, a pitman 28 of which one end is connected with the frame 26 has at its opposite end a split-strap 29 embracing an eccentric 30. The eccentric 30 is adj ustably secured upon a shaft 31 disposed below and crosswise of the main shaft 21, which latter has gear connections with the transverse shaft 31 of a character such that the shaft 31 rotates at one-half the speed of rotation of the main-shaft. The needle-bar 25 carries at its lower end a needle 32, which through the described connections and in combination with work-feeding mechanism is reciprocated endwise and vibrated laterally to effect the production of zigzag stitches.

Cooperating with the needle 32, below the throat-plate 10, is a loop-taker 33 of the rotary-hook type, said loop-taker carrying a mass of under thread around which the needle-thread loops are cast in the formation of lock-stitches. The actuating mechanism for the loop-taker 33 is substantially the same as disclosed in my prior Patent No. 1,729,994, Oct. 1, 1929. In general, the loop-taker is carried by a short, horizontally disposed shaft 34 carrying a bevel-gear 35 in mesh wi h a similar gear 36 upon the upper end of a vertically disposed, intermediate shaft 37 journaled in bearings provided within the post 6. At its lower end, the shaft 37 carries a bevelgear 38 driven by a gear 39 fixed upon the forward end of a loop-taker actuating shaft 40 journaled in suitable bearings provided at the under side of the bed-plate 1. The ratio of the gears 38 and 39 is such that the vertical shaft 37 rotates twice for each rota tion of the shaft 40. Secured upon the shaft 40 is a pulley 41 connected by a belt 42 with a pulley 43 upon the main-shaft 21, the shaft 40 rotating once for each rotation of said main-shaft.

To intermittently advance the work past the needle, there is employed a differential feeding mechanism comprising a main feeddog 44 operating through the feed-slots 11 in the throat-plate and an auxiliary feed-dog 45 operating through one of the feed-slots 11 and the feed-slot 12. The main feed-dog 44 has a lateral shank 46 secured by screws, as 47, upon a primary feed-dog carrier 48 from which projects a reinforcing lug 49 underlying the shank 46 of the feed-dog. The feed-dog carrier 48 has a transverse aperture 50 entered by a pivot-stud 51 projecting laterally from the upper end of a vertically directed, primary feed-lever 52. The feedlever 52 intermediate its ends has a transversely apertured hub 53 pivotally mounted upon a fulcrum-pin 54 disposed crosswise of the direction of feed and suitably fixed in bearing-bosses, as 55, within the frame post 6.

At its lower end, the feed-lever 52 is forked to embrace a slide-block 56 pivotally carried by a crank-arm 57 upon the forward end of a hollow main feed rock-shaft 58 journaled in bearing lugs, as 59, depending from the bedplate 1. At its rearward end, the rock-shaft 58 carries a crank-arm 60 pivotally connected with the lower end of a pitman 61, of which the upper end has a strap 62 embracing an eccentric 63 adj ustably secured upon the mainshaft 21 in substantially the manner disclosed in the U. S. patent to 1V. F. Dial et al., No. 718,988, Jan. 27, 1903.

The auxiliary feed-dog 45 also has a lateral shank 64 secured by screws, as 65, upon a feed-dog carrier 66 which likewise has a laterally extending reinforcing lug 67 underlying the shank 64. The carrier 66 has an upstanding ear 68 from which projects laterally a pivot-stud 69 entering an aperture in the upper end of a secondary feed-lever 7O disposed adjacent and extending in the same general direction as the primary feed-lever 52. The arrangement of the feed-levers and feed-dog carriers is such that adjacent sides of the latter are disposed in sliding engagement with each other, whereby they are materially strengthened against lateral stresses. The feed-dog carriers are further steadied by an arm 70 projecting laterally from the secondary feed-lever 70 and bent upwardly at its free end to slidingly engage the outer side of the primary feed-clog carrier 48. The carrier lugs 49 and 67 are arranged in substantial alinement in the direction of feed, the rear lug 49 of the main feed-dog carrier overhanging the upper edge of the auxiliary carrier 66 adjacent the car 68 thereof.

The secondary feed-lever 70 also has intermediate its ends an apertured hub 71 pivotally mounted upon the hub 53 of the feed-lever 52. At its lower end, the secondary feed-lever 70 is forked to embrace a slide-block 7 2 pivotally carried by a crank-arm 73 having a split hub 74 clamped upon the forward end of an auxiliary feed. rock-shaft 75 journaled in the main feed rock-shaft 58 with its opposite ends projecting beyond said rock-shaft 58. Suitably fixed upon the other projecting end of the auxiliary rock-shaft 75 is an arm 76 having a segmental groove 77 in the side thereof remote from the shaft end. Shift-ably disposed in. said groove 77 is a slide-block 78 pivotally connected with one end. of a link 79 of which the opposite end is connected by a pivot-bolt 80 with the pitman 61 intermediate the ends thereof.

Consequently the rock-shaft 75 is actuated by the reciprocatory movements of the pitman 61 which impart rocking movements to the shaft 58. However, the extent of movement of the rock-shaft 75 may n adjustably varied relatively to the rocking movements of the shaft 58. For this purpose, the slide- "lock 'Z8 is also pivotally connected "it-h one end of a link 81 of which the opposite end is connected in like manner with a rock-arm 82 having a hub 83 fixed upon a sleeve 81 journaled upon a fulcrum-shaft 85 disposed substantially parallel with the main-shaft 21. The fulcrum-shaft 85 is fixed in suitable bearings provided in opposite walls of the bracket-arm base 2. The sleeve 84; carries a wormwheel 86 in engagement with a worm 87 fixed upon an adjusting shaft 88 journaled in bearings in the front and rear Walls of the base 2, said adjusting-shaft 88 being disposed crosswise of and above the rock-shaft 85. The front bearing for the adjusting shaft 88 comprises a shouldered bushing 89, suitably fixed in an aperture in the base 2 and integral with a segment-plate 90 disposed in front of said base 2. The segment-plate 90 has an arcuate slot 91 in which stop- members 92 and 93 are adjustably fixed.

Suitably secured upon the end of the adjusting shaft 88, which projects forwardly beyond the segment-plate 90, is an adjustingarm 9% having offset end 95 overhanging the segment-plate 90. Threaded through the offset end 95 of the adjusting-arm is a securing screw 96 adapted to engage the circular periphery of said segment-plate, whereby the arm 91 may be adjustably clamped to th fixed segment-plate in different angular positions of said arm 94 and consequently in different positions of the slideblocl: 78 with respect to the axis of the rockshaft 75.

Rising and fallingmovements are imparted to the feed-dogs in substantially the manner disclosed in my before mentioned prior Patent No. 1,729,991. In brief, this mechanism comp-rises a vertically disposed feed-lift bar 97 to the lower end of which is adjustably secured a fork 98 straddling an eccentric 99 upon the loop-taker actuating shaft 10. The feed-lift bar 97, which is journaled for endwise reciprocation in suitable bearings provided within the post 6, has at its upper end fork 100 pivotally carrying between its members a pair of guide-blocks, as 101. The feed-dog carriers 4-8 and 66 are respectively provided with substantially horizontally directed slots 102 and 103 at their ends opposite to the iivotal connections of said carriers with the feed-bars, a guide-block 101 being slidingly disposed within each of said slots 102, 103. It will be understood from the foregoing description that work-advancingand return movements areimparted to the feed- dogs 44 and 45 by the feed- levers 52 and 7 0, d that rising anl falling movements are imparted to the feed-dogs about their pivotal connections with said feed-levers by the feed-lift bar 97. The extent of work-advancing movement of both feed-dogs may be determin d by adjustment of the eccentric 63 upon the main-shaft 21. the stroke of the auzc iliary feed-dog 15 being controlled independently of that of the primary feed-dog 44 by adjustment of the arm 94, as above described.

Opposed to the feed-dogs is a presser-foot carried by a main presser-bar 104; guided for vertically directed endwise movements in suitable bearings provided in the bracketarm head 5. This main resser-bar is yieldingly depressed by the usual spring (not shown) and may be raised and lowered by any manually operated means commonly employed for this purpose. Upon the lower end of the presser-bar 104 is secured by a screw 105 a presser-foot supporting bracket 106, of which aportion of its front face has a rectangular recess 107 having its spaced side walls vertically disposed. Snugly seated in the recess 107 and secured therein by a screw 108 is the vertically disposed, flattened shank 109 of the presser-foot, this construction providing not only for ready removal of the presser-foot from the machine but also for accurately attaching it to the presserbar. Projecting horizontally forward from opposite ends of the shank 109 are guidemembers 110 and 111 provided with vertically alined apertures in which are slidingly disposed the vertically directed auxiliary presser- bars 112 and 113. The lower ends of these auxiliary bars carry horizontally disposed shoes 11% and 115 entering the channeled heels 116 and 117 of presser- foot plates 118 and 119, which respectively terminate in upturned toes 120 and 121 and are pivotally mounted upon the shoes 114, 115 by horizontally disposed pivot pins, as 122, passing through the spaced members of the U shaped heels in a direction crosswise of the line of feed.

The foot- plates 118, 119 are yieldingly depressed independently of each other by springs 123 and 124 coiled about the auxiliary presser- bars 112, 118, said springs being interposed between the upper guide-member 110 of the presser-foot shank and collars 125 and 126 adjustably secured upon the bars 112, 113 to yieldingly rest upon the lower guide-member 111 and thereby limit the downward movement of the foot- plates 118, 119. The collars 125, 126 each have a depending guide-fin 127 slidingly disposed in a suitable guide-slot in the lower guide-member 111, whereby the bars 112, 113 are confined to vertically directed movements.

The foot- plates 118, 119 are spaced from each other beginning from the toes 120, 121 thereof to form a fabric-margin slot 128 which terminates at a point directly in front of the needle path, at which point the adjacent edges of the foot-plates curve inwardly into abutting relation to together form a split guide-web 129 which serves to deflect under the presser-foot the upwardly directed fabric margins passing through the slot 128. The guide-web 129 which also terminates in front of the needle-path, is comparatively narrow in the direction of seam formation, the adjacent edges of the foot-plates rearwardiy of said guide-web being cut away to merge into the foot- plate heels 116, 117.

This construction of the foot-plates provides a substantial space between the heels 116, 117 thereof, in which space is disposed an auxiliary or chaining-off foot having its toe spaced rearwardly from the guideweb 129 in the line of scam formation to provide a needle slot 131 in the presser-foot. The auxiliary foot 130 is preferably rigidly carried by a shouldered guide-bar 132 of which the lower portion is slidingly disposed in a vertically directed aperture provided in a guide-block 133 upon the presser-foot shank 109. The reduced upper end of the guidebar 132 is disposed within a screw-bushing 134 adjustably threaded into the upper side of the guide-block 133, a spring 135 coiled about the reduced portion of the guide-bar being interposed between the bushing 134 and the shoulder of the guide-bar. The foot 130 has an upturned heel 136 which overlies a bent stop-plate 137 secured by a screw 138 upon the rear side of the presser-foot shank 109, whereby downward movement of the foot 130 under the action of the spring 135 is limited. It will be observed that the crest 17 of the fabric-margin supporting member upon the throat-plate rises substantially centrally of the presser-foot slot 128 and that it is in alinement with the auxiliary foot 130.

The machine is provided with a mechanism for trimming the upturned fabric-margins passing through the presser-foot slot 128, said mechanism in the present instance including a horizontally disposed ledger-blade 139 and a horizontally vibratory cuttingblade 140 resting upon the ledger-blade, the cutting edges of said blades meeting in shearing relationship directly above the foot slot 128 and in advance of the guide-web 129.

The ledger-blade 139 is rigidly clamped in a split head 141 of a collar 142 suitably secured upon the lower end of a vertically slidable rod 143 jonrnaled in spaced lugs 144 formed on an auxiliary bracket 145 secured by screws as 146, upon a primary bracket 147 fixed by screws, as 148, upon the rear side of the machine head 4. The rod 143 is restrained against oscillation about its longitudinal axis by a forked guide-collar 149 adjustably c rried by said rod and embracing a guide-rib 150 on the bracket 145. Underlying the collar 149 is a lip 151 projecting laterally from a stop-member 152 secured for vertical adjustment upon the presser-foot supporting bracket 106. The stop-member 152 limits the downward movement of the rod 143, the adjustment being preferably such that the ledger-blade clears the presscr-foot plate 118 a sufficient distance to allow for rocking movements of the foot-plate 118 about its pivotal support while riding uneven portions of the work. The stop-member 152 also functions to raise the trimmer-blades when the presser-foot is raised for insertion and removal of work. It will be observed that the described construction furthermore provides for adj ustably raising and lowering the trimming position with respect to the work-support.

The cutting-blade 140 is rigidly clamped in a holder-collar 153 carried by a rod 154 slidably disposed in vertically alined apertures provided in spaced lugs, as 155, projecting forwardly from a rock-arm 156. A spring 157 is coiled about the rod 154 and is interposed between the upper of the lugs and a forked guide-collar 158 adjustably secured upon the rod above the lower lug 155, whereby the cutting-blade 140 is yieldingly urged into engagement with the ledger-blade 139 which it overlies. The rock-arm 156 has a split hub 159 clamped by a screw 160 upon a sleeve 161 journaled for oscillatory movements upon a vertically disposed fulcrumpin 162 fixed in vertically spaced bearin lugs, as 163, upon the primary bracket 14 7. Projecting laterally from the upper end of the sleeve 161 is an arm 164 connected by an extensible link 165 with an arm 166 depending from one end of a horizontally disposed rockshaft 167 journaled in a bracket 168 suitably secured to the underside of the machine bracket-arm 3. The other end of the rock-shaft 167 carries a crank-arm 169 pivotally connected with a pitman 170 having a strap embracing an eccentric 171 upon the main shaft 21. It will be observed that the ledger-blade 139 and its supporting means can be removed from the machine independently of the other blade supporting means by detaching the auxiliary bracket 145 from the machine bracket-arm, and that the entire trimmer-blade supporting mechanism can be removed as a unit from the machine by detaching the primary bracket 147.

Secured upon the foot- plates 118, 119, for individual detachment therefrom and disposed adjacent to the fabricslot 128 therebetween, are guard- blocks 172 and 173 provided in their under faces with recesses 174 and 175 affording the necessary clearance for the trimmer- blades 139, 140, which project through said recesses, to allow the foot- plates 118, 119 to rock slightly about their pivotal supports during the passage of the work without affecting the trimming position. The side face 176 of the guard-block 173 adjacent the slot 128 is gradually curved towards its rearward end to extend across said slot 128 and merge with the rearward wall of a slot 177 formed in the guard-block 172, whereby the trimmed-01f portion of the work is diverted laterally out of the seam line. Conforming with the diverting-surface curvature of said blocks and disposed directly thereabove in its operative position so as to cooperate with said surface in deflecting the trimmed-off fabric margins, is a diverterblade 17 8 having its shank 179 bent to closely embrace the ledger-blade carrying collar 142. The curved shank 179 of the diverter blade has a horizontally elongated slot 180 entered by the stop-screw 181 threaded into said collar and passing through a friction washer 182. This construction provides simple supporting means for the diverter-blade, permitting the blade to be readily swung into and out of operative position. Because the function of diverter-blades of this character is well known, the drawings show the blade as swung into its ineffective position to more clearly illustrate the mechanism 1n partobscured by the blade in its operative position.

In its passage to the needle from a suitably located supply, the needle-thread 1s led through guide apertures, as 183, formed 1n spaced thread-guiding arms, as 184, suitably secured upon the removable cover-plate 185 of the machine bracket-arm. Between said arms, the thread is passed through an aperture 186 in a pull-off lever-arm 187 pro ectlng through a suitable opening (not shown) in the cover-plate 185. The pull-0E lever 1s secured intermediate its ends upon a rocking fulcrum-pin 188 journaled in a pair of brackets, as 189, suitably fixed to the underside of said cover-plate 185. At its lower end, the pull-off lever is bifurcated to provide a fork 190 straddling an eccentric 191 upon the malnshaft 21. Adjustably secured upon the fulcrum-pin 188, as by a set-screw 192, is an arm 193 positioned to engage the lower end of a vertically disposed nipper-pin 194 Secured upon the upper end of the pin 194 is a clampdisk 195 urged by a spring 196 into engagement with the upper face of a nipper-member 197 fixed upon the cover plate 185. The thread-nipper referred to is located between the pull-0E arm 187 and the usual take-up arm 198, the needle thread after leaving the pull-01f device passing under the clamp-disk 195 and through the thread-guide 199 to the take-up.

From an inspection of Fig. 2 of the drawings, it will be observed that the pull-off arm 187 moves forwardly from between the thread-guides 184 to pull thread from the supply at the time that the nipper-pin 194 is depressed to cause the clamp-disk 195 to nip the thread and that the nipper-pin 194 is raised by the arm 198 during the return movement of the pull-off arm 187 to give up the thread pulled from the supply.

Any suitable or well known means may be employed for releasing the thread-nipper, as for instance for the purpose of removing the work from the machine. In the present machine there is employed a nipper-releasing lever 200 which is fulcrumed upon the machine bracket-arm 4 and has operative connections (not shown) with the usual presserfoot lifting means. The lever 200 has a wedge-shaped nose 201 positioned to enter between the clamp-disk 195 and the nippermember 197 when the presser-foot is raised, to thereby release the thread.

V In order to join fabric plies by a butt seam, the marginal portions of such plies upon the work-supporting post are directed upwardly to pass through the presser-foot slot 128, whereupon the shearing elements 139, 140 trim said margins and the trimmed ofl' surplus is directed laterally out of thepath of the needle by the merging diverting surfaces of the guard- blocks 172, 173, aided by the diverter blade 17 8. The trimmed ofi margins of the plies are then forced downwardly into abutting relation by the presser-foot guideweb 129 during the advance of the work by the feeding mechanism. As the auxiliary feed-dog 45 operates only at one side of the line of seam formation, it acts only upon one of the fabric-plies and accordingly this ply may be more or less shirred by adjusting the stroke of said auxiliary feed-dog with respect to that of the main feed-dog 44. It will be understood, of course, that in order to full or gather both fabric plies it is only necessary to employ an auxiliary feed-dog shaped to eX- tend upon opposite sides of the line of feed.

The abutting fabric plies are joined by a zigzag-stitch seam formed by the vertically reciprocating and laterally vibrating needle 32 in conjunction with the loop-taker mechanism beneath the throat-plate. The presserfoot plates 118, 119 are each capable of riding uneven portions of the work by reason of their pivotal and bodily yielding support upon the presser-foot body and can readily adapt themselves to differences in thicknesses of the fabric plies being joined. The auxiliary foot 130 rides the seam formed and, as usual, opposes a portion of the feed-dog in the absence of work to assist in chaining off.

While the seam formed by the present machine is not in itself novel, it presents advantageous characteristics over the multiple-needle, cross-thread seam employed for joining fabric sections, in that it is less bulky, requires only a relatively small quantity of thread and has more than ample strength to securely join the fabrics. particularly designed to conveniently handle the work and to join fabric sections at a high speed of operation.

Having thus set forth the nature of the invention, What 1 claim herein is 1. Feeding mechanism for sewing machines including a feed-dog carrier, a feed rock-shaft, operative connections with said rock-shaft for transmitting work-advancing and return movements to said feed-dog carrier, a crank-arm carried by the feed rockshaft, an actuating element, a'shiftable member connecting said element and the crankarm, and means for shifting said member endwise of said crank-arm for adjustably determining the extent of work-advancing movement of the feed-dog carrier comprising, a rock-arm operatively connected with the member, a feed-adjusting shaft, intermeshing gears coaxial with said feed-adjusting shaftand rock-arm, and means for actuating the feed-adjusting shaft.

2. Feeding mechanism for sewing machines including a feed-dog carrier, a feed rock-shaft, operative connections with said rock-shaft for transmitting work-advancing and return movements to said feed-dog carrier, a crank-arm carried by the feed rockshaft, an actuating element, a shiftable member connecting said element and the crankarm, and means for shifting said member endwise of said crank-arm for adjustably cletermining the extent of work-advancing movement of the feed-dog carrier comprising, a rock-arm operatively connected with the shiftable member having its fulcrum-axis substantially parallel with the feed rockshaft, a feed-adjusting shaft disposed transversely of said rock-arm fulcrum-axis, wormgearing connecting the feed-adjusting shaft with said rock-arm, and an operating member carried by the feed-adjusting shaft.

3. Feeding mechanism for sewing machines including a feed-dog carrier, a feed rock-shaft, operative connections with said rock-shaft for transmitting work-advancing and return movements to said feed-dog carrier, a cra11k-arm carried by the feed rockshaft, an actuating element, a shiftable member connecting said element and the crankarm, and means for shifting said member endwise of said crank-arm for adjustably determining the extent of work-advancing movement of the feed-dog carrier comprising, a rock-arm operatively connected with the shiftable member having its fulcrum-axis substantially parallel with the feed rockshaft, a feed-adjusting shaft disposed transversely of said rock-arm fulcrum-axis, wormgearing connecting the feed-adjusting shaft with said rock-arm, astationary segmentplate, an operating member carrier by the feed-adjusting shaft, means for adjustably securing said operating member to the segment-plate in angularly different positions of said feed-adjusting shaft, and stop-members carried by said segment-plate for adjustment into different positions in the path of movement of said operating member.

4. In a sewing machine having a bed-plate, a vertically disposed work-supporting post rising from said bed-plate, a reciprocatory needle, a loop-taker housed Within said post, a pair of feed-dog carriers disposed within the upper end of said post with adjacent sides of said carriers in sliding engagement, a pair of vertically directed feed-levers within the post pivotally connected at their upper ends with the feed-dog carriers a coaxial pivotal 7 support for said feed-levers intermediate the ends thereof, actuating mechanism connected with the lower ends of said feed-levers for imparting work-advancing movements to the feed-dog carriers, a vertically reciprocatory feed-lift bar within the post, means for actuating said bar, and connections with the feedlift bar for imparting rising and falling movements to both of the feed-dog carriers.

5. A differential feeding mechanism for sewing machines comprising main and auxiliary feed-dog carriers disposed with adjacent vertical sides thereof in sliding engagement, a pair of vertically disposed feed-levers pivotally connected with said carriers, one of said feed-levers having a bent arm slidingly embracing both of the feed-dog carriers, a coaxial pivotal support for the feed-levers, actuating mechanism for rocking said feedlevers including means whereby the stroke of one feed-dog carrier may be varied with respect to that of the other, and a vertically reciprocatory feed-lift bar for imparting rising and falling movements to both of said feed-dog carriers.

6. In a sewing machine having a bed-plate, a vertically disposed work-supporting post rising from said bed-plate, a reciprocatory needle, a loop-taker housed within said post, a rotary loop-taker actuating shaft journaled beneath the bed-plate, a pair of feeddog carriers disposed Within the upper end of the post, a pair of vertically disposed feedlevers within the post pivotally connected at their upper ends with the feed-dog carriers, a coaxial pivotal support for said feedlevers intermediate the ends thereof, coaxial feed rock-shafts journaled beneath the bedplate operatively connected with the feedlevers, means for actuating said rock-shafts, means accessibly presented to an operator in the operative position of the machine for efi'ecting adjustment of the stroke of one feedlever with respect to that of the other, a vertically reciprocatory feed-lift bar within the post, and means for actuating said feed-lift bar from the loop-taker actuating shaft.

7. Differential feeding mechanism for sewing machines comprising, main and auxiliary feed-dogs, means for imparting rising and falling movements to said feed-dogs, and means for imparting w0rk-advancing and return movements to the feed-dogs including a pair of coaxially arranged feed rock-shafts, a pitman operatively connected with one of said rock-shafts, a crank-arm carried by the other rock-shaft, a member shiftably disposed upon said crank-arm, a link-connection between said member and said pitman, a rockarm operatively connected with the shiftable member, and adjusting means including gear connections wit-h said rock-arm for determin- 7 ing the effective action of said link-connection upon the rock-shaft crank-arm, whereby the extent of work-advancing movement of one feed-dog may be adjusted with respect to that of the other feed-dog.

In testimony whereof, I have signed my name to this specification.

FREDERIG M. CARD.

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