US1317613A - brogan - Google Patents

Description

M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED Aue.12.1915.

Patented Sept. 30,1919.

l3 SHEhTSSHEET l.

MrF. BROGAN.

SEWING MACHINE.

APPUCATION FILED AUG.12, 1915.

Patented Sept. 30, 1919.

13 SHEETSSHEET 2.

.ffi 492 I l I n 1/ M. F. BROGAN.

SEWING MACHINE.

APPLICATION min AUG. 12, I915.

Patented Sept. 30, 1919.

I3 SHEtfS-SHEET 3.

M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED AUG.12.19I5.

Patented Sept. 30, 1919.

13 SHELI'SSHEET 4.

M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED Aumz, 1915.

Patented Sept. 30, 1919.

13 SHEETSSHEET 5.

M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED AUG.I2. I915.

1 ,3 1 7, 6 1 3 I Patented Sept. 30, 1919.

13 SHEhTSSHEET 6.

5 193 fig wen- M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED AUG. 12. 1915.

Patented Sept. 30, 1919.

13 SHEETSSHEET 7.

7 yg a M. F. BROGAN.

SEWING MACHINE. APPLICATION FILED AUG.12, 1915 1,3 1 7,6 1 3 Patented Sept. 30, 1919.

I3 SHEhTSSHEET B.

M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED AUG. 12, 1915.

1 ,3 l 7, 6 1 3 Patented Sept. 30, 1919.

I3 SHEhTS-SHEET 9.

M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED AUG. 12, 1915.

1,817,613. I PatentedSept.30,1919.

I3 SHEhTS-SHEET I0.

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M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED AUG.I2, 1915.

Patented Sept. 30, 1919.

' M. F. BROGAN.

SEWING MACHINE.

APPLICATION FILED AUG. 12, 19l5.

Patented Sept. 30,- 1919.

13 SHEETSSHEET l2.

M. F. BROGAN.

SEWING MACHINE. APPLICATION FILED AUG. I2, 1915.

Patented Sept. 30, 1919.

.13 SHEETS-SHEET I3- MICHAEL F. BROGAJN', OF LAWRENCE, MASSACHUSETTS, ASSIGN'OR, BY MESNE ASSIGN- MENTS, T0 UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY,

A CORPORATION OF NEW JERSEY.

SEWING-MACHINE.

\ Specification of Letters Patent.

Patented Sept. 30, 1919.

Application filed August 12, 1915. Serial No. 45,218.

To all whom it may concern Be it known that 1, MICHAEL F. BROGAN, a citizen of the United States, residing at Lawrence, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Sewing-Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

-The present invention relates to an improvement in sewing machines, and more particularly to lock stitch wax thread sewing machines.

Heretofore, the lock stitch sewing machine has employed a single aw-l and a single needle and other cooperating instrumentalities in the formation of the stitch, and, obviously, the limit of the rate of speed at which the machine can be operated is determined by the rate of speed at which'the stitches can be formed and set. Taking the outsole stitcher, for example, the speed at which it can be operated in sewing outseams is determined in a large measure by the rate at which the stitches can be formed and set in the materials, one stitch at a time. The principal object of the present invention is to produce a lock stitch sewing machine in which two stitches are formed at each cycle of operations of the machine.

According to this invention, if the speed of the machine be maintained the same as before, the rate of seam formation will be doubled, or if the speed of the machine be reduced, still the output of the machine will be materially increased, or if the speed of the machine be halved, for example, the

rate of seam formation will be maintained 7 the same as before, thereby in the first example do-ubling the output, or in the second example materially increasing it, or in the third example maintaining the output the same. In the latter two examples, the speed of the machine being materially decreased, the rate of Wear of the machine is reduced, and the life of the machine is much increased. The machine of the present invention contemplate other features of novelty, hereinafter referred to and particularly pointed out in the claims.

'In the accompanying drawings illustratshuttle and associated parts;

tension wheel takeup, auxiliary takeup,

thread measurer, and associated parts;

Fig. 7 is a right end elevation with the fourth cam removed;

Fig. 8 is a top plan view of the machine, with the cam shaft and cams removed, the

cam shaft bearing and certain other parts being shown in sectional plan;

Fig. 9 is a front sectional elevation of the Fig. 10 is a horizontal section on line 1010, Fig.' 9, looking in the direction of the arrows;

Fig. 11 is a back view of the shuttle driver plate;

Fig. 12'is a side elevation of the shuttle;

Fig. 13 is a left side elevation of the fourth cam disk;

Fig. 14 is a left side elevation of the second cam disk;

Fig. 15 is a development of the peripheral face of the first cam disk;

Figs. 16, 17' and 18 are similar development-s of the second, third and fourth cam disk faces respectively; 1 Fig. 19 is an enlarged front elevation of a portion of the machine shown with the work in position, with the needles looped ready to draw bights of the under or needle thread up through the material;

Fig. 20 is a similar view after the needles have risen and drawn bights of thread up through the material, and while the spreader holds the loops'thus drawn up open, ready to receive the shuttle;

. Fig. 21 is 'a similar view, showing the two bights of thread after the shuttle horns have entered them;

Fig. 22 is a similar view, showing the position of the parts after the loop of the second stitch has been cast of? b the shuttle, and just before the loop of t e first stitch is cast off by the shuttle;

Fig. 23 is a fragmentary right side elevation showing the bights of thread drawn up through the materials by the needles held open by the spreader, ready for the passage therethrough of the shuttle;

Fig. 24 shows the position of the takeup and associated parts after the needles have drawn their bights of thread up through the materials;

Fig. 25 is an enlarged front sectional elevation of the work, work table or work support, and associated parts, showing diagrammatically the position of the thread after the looping operation is completed;

Fig. 26 is a plan of the loops; and

Fig. 27 illustrates diagrammatically seven steps in the formation of two stitches of a seam.

The invention is shown as embodied in a machine of the type of the Goodyear rapid outsole stitcher, the general form and mode of operation of which are illustrated and described with substantial accuracy in the French and Meyer Patent No. 473,870.

Before entering upon a detailed description of the various parts ofthe machine, it will be convenient first to refer to certain general features as a preliminary thereto. The main, cam shaft S carries on its lefthand end the driving pulley, and. on its right-hand end is connected with the usual revolution counter. This main cam shaft S is supported in bearings at its opposite ends, and carries four cams, which are herein designated as the first, second, third and fourth. cams, beginning with the left-hand cam and counting to the right. These several cam disks may be referred to 'by the names of some of the conspicuous parts operated by them. Thus, the first cam 1 is conveniently. termed the take-up cam disk,

the second cam 2 is called the shuttle or needle cam disk, the third cam 3 is called 11 pivoted on the lever shaft 12 and carrying a cam roll which engages a cam path 13 in the right side of the cam disk 2 (Fi 1 and 14). The needle uide 14 (Fig. 23 is providedwith two he es to receive the twonee dles, and it has a segment 15 which is engaged by the pinion 16 mounted on the shaft 17, and which carries upon its left-hand end a segmental pinion 18 (Fig. 8) driven by the segmental gear 19 pivoted at 20 on the frame of the machine, being actuated by an arm 21 carrying a cam roll 22 which engages a cam path 23 (Fig. 5), being the inner cam path, that is, the one nearer the shaft in the right-hand side of the cam disk 1. By reference to Fig. 23, it will be observed that the two needles are of different lengths Of these the left-hand needle, viewed facing the machine, is the longer, and the right-hand one is the shorter. This is for convenience in looping. The needle'cam path 13 is so shaped as to cause the needles to descend and enter and pass through the work, receive the thread in their barbs, and to withdraw, pulling two loops or bights of thread through the materials. From an examination of the cam path of Fig. 14, it will be observed that the needles are held stationary in their upper position for nearly one-half the revolution of themain shaft, that they descend quickly, and are then dipped slightly to facilitate the operation of the looper, and then withdrawn from the material to their retracted position and-advanced slightly therefrom to disengage themselves from the loops of thread drawn up by them, after which they move rearwardly again and then stand fast until they are again operated as before. The needle guide performs its usual function'of supporting the needles. I

The first needle, that is, the left-hand needle, as viewed in Fig. 3, is subjected to a lateral strain during the looping operation, as will hereinafter appear, owing to the pull of the thread thereon. At this time it is supported against lateral strain by a needle support 30 which is mounted on'the end of the needle-supporting lever 31 (Fig. 4) pivoted at 32, carrying upon its rear end a pin 33 (Fig. 8), adapted to engage the side of the cam 34 mounted upon and projecting from the periphery of the cam disk 1. This needle support 30 carries a thread guard 35 near its needle-supporting end, which prevents the thread from becoming entangled with the needle sup ort and other parts.

The two awls A Fig.- 19) arecarried by the awl segment 40 (Fig. 4), pivoted at 41 on the feed slide in the usual manner. The awl segment 40 is actuated by the awl segment lever 42 (Fig' 7) pivoted at its rear end upon the lever shaft 12 and bearing a cam roll 43 which is received in the awl cam path 44 of the cam on the left side of the cam disk 3. The shape of the awl cam ath is such as to cause the awls to be force up into and through the material or stock M to gins, but they remain in engagement with ho sewed, after which their retraction be the material during the time they are moving laterally to feed the work, after which, and as the needles descend, their retraction is completed. The awl segment is mounted upon the feed slide F (Fig. 7 which is mounted in the usual guides and actuated by the feed lever 50 (Fig. 8) pivoted at 51 upon a stationary part of the machine, carrying upon its front end a groove which receives the pin 52 attached to the feed regulating lever 53, and carrying upon its rear end a cam roll 54 which engages a feed cam path 55 in the feed cam disk 4 (Fig. 18). The throw of this cam is such as to reciprocate the feed slide the length of two stitches, or double the distance between the aWls and between the needles.

It is to be observed that the distance between two stitches simultaneously made by the two needles is fixed and constant, and that the distance between this pair of needle holes and the next pair of needle holes may be varied by adjustment of the feed regulating lever. While it is preferred to have the feed of such a length as to make the distance between the last hole of one pair of needle holes and the first hole of the next pair of needle holes the same as the distance between the needle holes of each pair, it is not a matter of substantial consequence if every other stitch depart slightly from this length, as it would not constitute a detriment to the finished work. Thus, in stitching outsoles, that portion of the seam extending around the forepart should preferably have all of the stitches of uniform length, while along the shank the stitches might vary in length without prejudice to the acceptability of the work, because this portion of the seam is not conspicuous, and in fact is rarely to be seen by the user of the shoe.

The looper L is mounted on the end of the looper lever 60 (Fig. 8), which is slidingly mounted in the-looper carrier 61 pivotally supported at 62 upona stationary part of the frame of the machine. The lateral position of the looper is determined by swinging the looper carrier 61 upon its pivot. This swinging motion is imparted to the looper carrier by means of the lateral looper cam roll 63 mounted upon the forward portion 64 of the looper carrier 61, which lateral looper cam roll 63 engages the cam path 65 (Fig. 16) in the periphery of the cam disk 2. The forward and back movements of the looper are imparted by the looper bell crank lever 66, one arm of which engages a block pinned on the loo-per lever 60, and the other arm of which carries the-forward and back looper cam roll 67 which engages the cam path 68- (Fig. 17) in the periphery of the cam disk 3. These two levers operate to move the looper in a path to lay the thread over the thread hooks and in the barbs of the needles. At the end of the formation of a pair of stitches the looper stands with its eye 69 in line with the thread extending from the work to the take-up. The looper first moves from this position to the rear of the thread hook 70 (Figs. 25 and 26), thence to the right behind the thread hook 71, and on to the right and in front of and beyond the first needle N, thence rearwardly and around the needle, laying the thread in the barb thereof, thence to the left and in front of the thread hook 71, around behind it, and thence to the right in the rear of the first needle, then forward, and then on to the right (at which time the needles move downward), laying the thread in the barb of the second needle, thus forming two loops or bights of thread, the first of. which is of sufficient size to permit the shuttle to pass through it and the second of which is of sufficient size to see the needle through the work and to the extremity of its retracting stroke without reeving through the barb or hook of the needle. thread necessary to enlarge this second loop sufliciently to permit the shuttle to pass through it is drawn up by the shuttle itself.) The two thread hooks 70 and 71 are mounted upon stationary parts of the machine (see Figs. 19 and 4) -near and to the left of the sewing point, the thread hook 71 being pivoted at 72 upon the left-hand end of the work support NV, and the thread hook 70 being pivoted at 73 upon an arm 74 projected to the left from the left-hand end of the work support W. The thread hook 7 is locked in operative position, as shown in Fig. 19, by'means of the thread hook lock 75 (see also Fig. 4) which is formed upon the forward end of a lever 76 pivoted at 32 (Figs. 4 and 8), which lever carries on its rearend' a cam roll 77 adapted toengage the cam path 78 in the periphery of the cam disk 1. During the time the needle is looping the thread around the thread hooks and barbs of the needles, the thread hook lock 75 occupies the-position shown in Figs. 4, 8 and 19, engaging the upwardly projecting portion 80 of the thread hook carrier 81 so as thereby to prevent the thread hook 70 from being turned upon its pivot by the tension of the thread thereon. The link 82 connects the thread hook 7 0 and the thread hook 71, and when the thread hook 70 is held from movement, the thread hook 71 is likewise held. A spring 83 attached to the upper part of the thread hook carrier 81 normally holds the thread hooks in the position shown in Fig. 19 with yielding force so that when the thread hook lock is moved away from the thread hook carrier 80 and sufficient tension is exerted upon the thread, the thread hooks 70 and 71 will turn and thereby disengage themselves from the loops of thread held thereby. The thread book 70 is secured to (The remainder of thethe thread hook carrier 81 by a screw 84 (Fig. 25), the carrier being slotted so as thereby to permit adjustment ofthe position of thread hook 70 to secure the proper length of loop held by it.

The work support, or work table, W, above referred to in connection with the thread hooks 70 and 71, occupies the conventional position for supporting the work,

having a fiat top provided with a long slotto receive the awls and to permit their feeding movement to feed them into position opposite the needles. It also has a depending apron or front which protects thev shoe upper from contacting with the awls, looper and needles. It is provided in its front side with a hole 90 located between the needle positions to receive a lower thread retainer 91 (Figs. 4, 19, 23 and 25). This thread retainer 91 is supported in a hole in a stationary part of the machine, specifically the needle segment support. This lower thread retainer 91 has a shank which is cylindrical in form; its operative end is rectangular and somewhat thinner than the distance between the needles; it is actuated by a lever 92 (Figs. 4, 8 and 9)' arranged below the work support and pivoted at 93 on a stationary part of the machine. The other end of the lever 92 is slotted at 94 and in the slot is received a pin 95 supported in the thread hook lock lever 76. The lower side of the shank of the lower thread retainer 91 is transversely slot-ted to receive the end of the lower thread retainer operating lever 92. The arrangement is such that when the forward end of the thread hook lock lever moves to the right it causes the lower thread retainer operating lever 92 to be swung so as to retract or move back the lower thread retainer, and vice versa. Thus, when the needles are being looped, at which time the thread hooks are held fixed, the lower thread retainer is in retracted position, but as soon as the thread hooks are released the lower thread retainer is moved forward into position between the needles so that as the needles draw up their two bights of thread, the thread extending from the first needle hole to the second needle hole is bent around. the lower thread retainer. Thus, with the parts in'the position shown in Fig. 19, the lower thread retainer 91 is in retracted position, while, when the parts are in the positions illustrated in Fig. 20 the lower thread retainer has been forced forward and engages the thread between the stitch holes during the time the shuttle is passing through the loops drawn up by the needles. 1

The tension wheel T mounted on a stationary part of the machine receives the thread 100 coming from the waX pot, which thread passes entirely around the tension wheel and thence around a thread truck 101 from which it passes on to the thread measurer 102. After passing over the thread truck on the thread measurer, the thread passes down around the thread truck 103, thence up over one of the thread trucks '104 of the auxiliary take-up or slack thread controller 105 from which it passes to one of the thread trucks106 on the take-up 110, from which it passes around the other thread truck 104 of the auxiliary take-up and thence down around theother thread truck 106 of the take-up 110, from which it passes through the thread eye 111 to the eye 69 of the looper L. It will be noted that there are two thread trucks 104 and two thread trucks 106. This is because of the large amount of thread necessary to be handled owing to the passing of two loops over the shuttle at each cycle of operations.

The thread trucks 101 and 103 are both of them thread lock trucks, the thread lock 112 being arranged between the two thread trucks 101 and 103 and adapted to engage the thread on either the one or the other, or neither, as the case may be. This thread lock 112 is pivotally mounted on the pivot 113 and provided with a rearwardextension 114 which is received in a notch 115 in the disk 11'6 mounted on'the rock shaft 117. To this rock shaft 117 is attached an arm 120 which is connected by means of the link 121 with the bell crank lever 122 pivoted at 123 on a stationary part of the machine, which bell crank lever 123 carries upon its end a cam roll 124 which engages the outer cam path 125 in the right-hand side of the cam disk 1 (Fig. 5). The throws of this cam path are such that the thread is locked against being pulled from the tension while the looper is looping the needles and thread hooks, thus preventing thread from being stolen from the tension during such operathread truck 103, and during the latter part of the looping operation the thread is locked against the thread truck 101. x

. The thread measurer or pull-off 102 is mounted on the rock shaft 130 supported in a stationary part of the machine which shaft carries upon its right-hand end an arm 131 which is actuated to oscillate the shaft 130 through the mechanism constructed and organized substantially as in said patented machine, except that owing to the increased amount of thread necessary to be pulled off from the tension by the thread measurer, due to the requirement that the thread for the eration, the thread is locked against the with a cam 140, the operating surface 141 of in a shuttle race 170.

formation of two stitches is pulled off at each cycle of operations, the amplitude of oscillation of the thread measurer is increased, as a consequence of which the harp 132 is widened to accommodate the larger throw of the link 133' connected with the bell crank lever 134. Provision is also made for adjustment of the position of attachment of the link 133 to the depending arm of the bell crank lever 134 to accommodate the thread measurer to different qualities of stock and different tightnesses of seam. The forwardly extended arm of the bell crank lever 134 carries upon its end the cam roll 135 (Fig. 2), which engages thecam path 136 (Fig. 13) on the left-hand side of the cam disk 4.

The take-up arm 110 (Fig. 6) is provided which is adapted to engage the pin 142 of the spring-controlled auxiliary take-up lock 143. This auxiliary take-up lock. 143 consists of a lever pivoted at 144 on a stationary part of the machine. It has a hook at its end which engages a hook 145 on the lower side of the auxiliary take-up. At times when the cam surface 141 is in engagement with the pin 142, the hook is prevented from engaging the hook 145. The auxiliary. take-up lock 143 is a two-part affair consisting of a lever 146 to which is secured the part 147 provided with the slot 148 to receive the screw 149 by which the two parts are adjustably connected. This holds the auxiliary take-up from action during the first part of the looping operation, that is, during the time the looper is moving from its position near the sewing int out around the thread hook and a out half way back to the first needle, but it is released for subsequent operations The takeup 110, pivoted at 113,-has an arm 160 connected by a link 161 with a take-up cam lever 162v pivoted at 163 on a stationary part of the machine and provided on its upper end with a cam roll which engages the cam path 164 in the left side of the cam. disk 1. The take-up is operated by this mechanism to give up thread .to the' looper during the looping operation, to pull back or take up the needle loops and to tighten and set the first stitch in a manner more particularly hereinafter described inv connection with the description of the operation of the machine.

- The shuttle, or loop taker, S oscillates on a horizontal axis and in a vertical plane at the front of the machine. It is supported The shuttle has a horn 171 and a bobbin case 172 which receives the spool of shuttle thread 173. The

thence over the hinge of the shuttle tension and thread locking device 17 6, pivoted at 177 to the periphery of the bobbin case, thence back through the hole 178 under the hinged shuttle tension and thread locking device 17 6, thence along between the device and the bobbin case, out through the hole 179, along the outer surface of this locking device 176, back under it again through the hole 180, and thence radially inward under the shuttle take-up member 181 (Fig. 19) j the center of the shuttle may be increased or diminished so as thereby to increase or diminish its eccentricity with relation thereto, to increase and diminish the amount of shuttle'thread taken up in setting the second stitch. It is convenient here to remark that, as already pointed out, the first stitch is set by the take-up and the second stitch is set by the shuttle, the thread lock being pulled down into the material by the take-up so that the thread lock of the first stitch is near the top of the work and the thread lock of the second stitch is pulled up into the material by the shuttle leaving the lock near the lower surface of the work. The shuttle is provided with a shuttle thread clamping pin 190 (Figs. 9 and 19) which is received in a hole in the shuttle and engages with its inner end the outside of the shuttle thread tension device 17 6, and engages with its other end the ball 191 which normally projects slightly beyond the surface of the shuttle and is adapted-to engage the cam surface 192 on the shuttle race during the setting of the stitch by the shuttle. The bob bin case 172 is provided with a flange 193 which engages a corresponding flange on the shuttle (see Fig. 10), being held thereagainst by the screw 174 above referred to. The shuttle is cut away for a considerable portion of its periphery, as shown in Fig. 9, and the shuttle race is likewise cut away-for a long distance, this being required by the necessity for the shuttle s handling two loops of the lower or needle thread. In order to sustain the shuttle efficiently in a concentric position in the shuttle race so as to be capable of being oscillated without cramping, the shuttle is provided upon its periphery with a laterally projected flange 194 which, with the outer wall of the shuttle, forms a groove that receives the flange 195 of the shuttle retainer 196 secured to the shuttle race by the screws 197. The shuttle is actuated by the shuttle driver 200 which consists of a disk 201 on the end of a shuttle driving shaft received in the shuttle race and provided with two arms 202 and 203,

the former of which is received behind the.

'arms'is provided, of course, to receive the needle segment. They are united by a little bridge 204 which is provided to prevent the thread from accidentallyr 1catching udporfi tile e rear en 0 t e,

corners of these arms. shuttle driving shaft carries a bevel pinion 205 which is en aged by a segmental bevel gear 206 (Fig. 1 pivoted on the lever shaft 12 and bearing a stud carrying a cam roll 20'? which engages the cam path 208 in the left side of the cam disk 2. The shuttle driver 201 has a smooth front face so that nothing shall engage either of the loops of the thread passing between the shuttle and it while the shuttle is passing through the loops drawn up by the needles. The arm 202 of the shuttle driver is provided with a spring horn 210 which normally occupies a position alongside of and .slightly within the point of the horn 171 of the shuttle, as shown in Fig. 19. This spring horn is provided with a shank which is received in a hole in the shuttle arm 202 and is encircled by a torsion spring fastened at its front end .to the shuttle arm 202 and at its rear end to the disk 211. This disk 211 has a shoulder which takes against a stop 212, the disk being pinned to the shank of the horn 210.

When inserted in the shuttle the spring is put under tension so that it normally tends to turn the spring horn outward close to but within the shuttle horn 171. The shuttle horn 171 enters both of the loops of thread drawn up by the needle but the shuttle driver horn 210 enters only the loop-drawn up by the first needle. When the shuttle has turned to the position where it casts off the loops through which it is passing, the shuttle driver horn 210 casts off its loop after the other loop" has been cast off by its turn- 1ng movement, under the influence of the pull exerted by the loop'upon it against the action of this torsion spring. The description of the operation of the shuttle horn and shuttle driver horn will be elaborated in connection with the description of the operation of the machine.

The spreader or thread lifter 220 (Fig. 20) is provided with two hooks 221 and 222 adapted to engage, respectively, the loops drawn up by the first and second needles. The spreader 220 has a shank 228 which is secured in the front end of the spreader arm 224 (Fig. 23) pivoted at 225 on a stationary part of the machine. This spreader arm 224 has attached to it a rearwardly extended arm 226, which supports a pin carrying pivotally mounted thereon a block which is received in the jaw 227 at the front end of a lever 228 pivoted at its rear end upon the lever shaft 12 and bearing upon its side a stud carrying a cam roll 229 which is receivd in the cam path 230,being the inner cam path on the right side of the cam disk 3. When the needles are in their lowermost position the spreader is down (see Fig. 19) and the needles first draw up their two loops of thread, laying the. outer sides of the bights or loops of thread on the spreader hooks 221 and 222. The hooks do not extend toward each other beyond the adjacent sides of the needles,

so it is that the two sides of the loops of thread drawn up by the needles lying adjacent to each other are not caught by the spreader hooks. After the needles have retracted sufficiently to clear the spreader, the spreader rises to the position shown in Fig. 20, and the loops are thereby opened, as shown in Fig. 23, ready for the entrance of the shuttle.

After the loops have been drawn up by the needles, and before the shuttle enters the loops, an upper thread retainer or loop separator 240 (Fig.4) enters the space between the two loops of thread and separates the loops. This upper thread retainer or loop separator consists of a pin mounted on the end of the lever 241 pivoted at 242 on a part of the feed slide or awl carrier. The rear end of this lever 241 is connected by means of a link 243 with a lever 244 (Fig. 8) pivoted at 51 on a stationary part of the machine. The rear end of the lever 244 carries a cam roll 245 which engages the laterally acting cam 246 (Figs. 1, 3, l3 and 18) on the right side of the cam disk 4. This upper thread retainer or loop separator is operated to enter the space between the two loops and to separate the two loops during t e time the shuttle is passing through them, and it remains there until the takelup has pulled back upon the second loop of thread and pulled the shuttle thread down through the work. It thereby acts to provide a slackness in the shuttle thread between the last completed stitch and the second stitch which provides thread so as to sink the lock of the. first stitch into the material when the first stitchcomes to be set upon the continued movement of the take-up. It will beobserved that this cam 246 holds the upper thread retainer or loop separator retracted for the greater part of acam shaft revolution, so that for a short time only is v the loop retainer held between the two loops for the purpose of separating them and providing suflicientslack thread in the upper or shuttle thread to' sink the look into the materials.

After the setting of the first stitch by the take-up (which occurs after the upper thread retainer has been withdrawn) the abutment 250 (Fig. 4) is moved into the position illus:

trated in Figs. 4 and 8-, and it then engages the left-hand side of the shuttle thread running from the second needle hole to the shuttle and affords a support over which the shuttle thread may reeve during the setting of the second stitch by the shuttle. This abutment 250 is carried on the left-hand end of the lever 251 pivoted at 242 upon the feed slide or awl carrier. The link 253 connects the rear end of the lever 251 with the front end of the lever 254 pivoted at- 51, and carrying upon its rear end a cam roll 255 which. engages the laterally acting cam surface 256 on the left side of the cam disk 4.

The work clamp 260 (Figs. 4 and 7 is operated in the same general way as in the machine of said patent. It is mounted on the front end of a lever 261 pivoted at 262, carrying on its rear end the harp 132 which coiiperates with the thread measurer. To the work clamp or presser foot lever 261 is attached a spring rod 263 which is 'ac tuated by the arm 264 as in said patent, the latter arm 264 being lifted in timed 006peration with the other instrumentalities of the machine to cause the work clamp or presser foot to clamp and hold the ma terial by means of work clamp or presser foot actuating lever 265 which carries at its front end a pawl 266 which engages a ratchet 267 on the rear end of the arm 264. This lever 265 is pivoted at 268 on a stationary part of the machine, and carries upon its side a cam roll 269 which engages a cam path 270, being the outer cam path in the right side of the cam disk 3. The clamp releasing lever 280 is also pivoted at 262, and it carries upon its lower end the pawl pusher 281 which has two arms, one arm 282 which engages the pawl 266 to lift it, and the other arm 283 which engages the pawl 284, which engages the ratchet 285 on the rear end of the work clamp lever 261. N

Coming now to a description of the operation of the stitch-forming instrumentalities in forming a seam of stitches reference will be made more especially to Figs. 19, 20, 21, 22, 23, 24, 25 and 26, which shoW the parts in different-positions during the formation of a pair of stitches of a seam, and to Fig. 27 which shows the thread in different positions during one cycle of'operations of the machine. By reference to Figs. 25 and 27 it will be seen that the lock of the stitches is located alternately near the top of the material, as it is positioned in the machine, and near the bottom of the material, the lock of the first stitch being near the top and the lock of the second stitch being near the bottom.

After the awls have risen through the materials and formed two punctures therein to receive the needles, and the feed has taken place, the needles descend through the awl position 1, to the left, behind the needle hook 71, on behind and beyond the needle hook 70, thence forward, and then to the right behind the needle hook 71, the needles having descended through the materials by this time, thence in front of the left-hand needle end, then rearwardly, and then to the left, thereby laying the thread in the barb of the left-hand needle, thence it continues its movement to the left passing in front of the needle hook 71, then rearwardly and to the right back of the left-hand needle end to a position between the two needles, then the looper moves forwardly and the needles descend slightly, then the looper moves to the right and rearwardly, thereby laying the loop in the barb of the hook of the second needle, and the thread occupies the position illustrated in elevation in Fig. 25 and in plan in Fig. 26. The strain exerted by the thread upon the first needle would tend to pull it to the left. This strain is resisted by the needle support 30 which engages the side of-the first needle as soon as it has descended through the materials and just as the looper lays its thread in the barb thereof. By an examination of Fig. 25, it will be observed that the longer loop or bight 300, that is, the loop or bight held by the lefthand needle and the thread hook 70, is of sufficient length to see the needle back and to pass over the shuttle without reeving of the thread in the barb of the needle or around the material between the first needle and the second needle. The

second loop 310 is much shorter, and is sufficient to supply thread for the left side of the thread loop drawn back by the second needle, that is, sufiicient to see the needle back to the extreme of its throw without. reeving in the barb thereof, but it is not intended to be sufiicient to pass the thread over the shuttle, as it merely supplies thread for approximately one-half of the length required for that purpose, the other half of the thread for this loop or bight 310 being drawn by the needle or shuttle, or both, from below the work. By reference to Fig. 19, it will be seen that the take-up at this time is not completely raised during the formation of the second loop 310 of thread. After this, the needles rise, and the take-up also rises. and the parts assume the position illustrated in Figs. 20 and 23, that is, after the needles have partially risen, the spreader

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