US2352708A - Shoe sewing machine and driving and stopping mechanism therefor - Google Patents

Description

July 4, 1944. s 2,352,708

SHOE SEWING MACHINE AND DRIVING AND STOPPING MECHANISM THEREFOR Original Filed Sept. 14, 1939 6 Sheets-Sheet l 210 I L I K 502 500 O o E 146 P l L I &\ l

July 4, 1944. o. R. HMS 2,352,708

SHOE SEWING MACHINE AND DRIV ING AND STOPPING MECHANISM THEREFOR Original Filed Sept. 14, 1939 6 Sheets-Sheet 2 0. R. HAAs- July 4, 1944.

SHOE SEWING MACHINE AND DRIVING AND STOPPING MECHANISM THEREFOR 6 Sheets-Sheet 3 xf dw Original Filed Sept. 14, 1939 July 4, 1944. 0. s- 1 2,352,708

SHOE SEWING MACHINE AND DRIVING AND STOPPING MECHANISM THEREFOR Original Filed Sept. 14, 1939 6 Sheets-Sheet 4 O. R. HAAS July 4, 1944 SHOE SEWING MACHINE AND DRIVING AND STOPPING MECHANISM THEREFOR Original Filed Sept. 14/1939 6 Sheets-Sheet 5 y 1944- c R. HAAS I 2,352,708

SHOE SEWING MACHINE AND DRIVING AND STOPPING MECHANISM THEREFOR Original Filed Sept. 14, 1939 6 Sheets-Sheet 6 522 320 '190 1 92 v 262 f 19+ 2 260 I -av EA- I -270 I O Z66 D- Hrs 195 fivenfon Patented July 4, 1944 SHOE SEWING MACHINE AND DRIVING AND STOPPING MECHANISM THEREFOR Otto It. Haas, North Beverly, Mass., 'assignor to United Shoe Machinery Corporation, Fleming:

ton, N. J., a corporation of 'NevvjJerse'y' Original application September 14, 1939, Serial 1. No. 294,926. Divided and this application 00 tober 23, 1941, Serial No. 416,228

ture on the machine.

In order to avoid the necessity of careful or 22 Claims.

In a shoe sewing machine, the operating parts are ordinarily of heavy construction and suitable treadle controlled driving and stopping mechanisms are provided to control the speed of operation and to bring the machine to rest with the stitch forming devices free of the work so that the Work may readily be withdrawn at the end of the seam. In order to reduce the speed of the main sewing shaft of the machine and to rotate the shaft positively to astopping position, it is usual to provide a low speed driving mechanism in addition to a high speed driving mechanism which is employed to drive thesewing shaft during sewing operations. Where the'driving and stopping mechanism is controlled by a treadle actuated member, the high speed mechanism only is directly connected to the treadle member to be thrown into and out of operation thereby, the low speed mechanism being rendered operative automatically at a predetermined point in the rotation of the sewing shaft when the high speed mechanism is thrown out of operation. In use, there ordinarily is nothing to prevent the treadle controlled member from being actuated to throw out of operation the high speed driving mechanism at a position of the sewing shaftso close to the stopping point that the low speed driving mech anism either will not have an opportunity to act properly, thus causing a sudden impact in the machine, or a failure on the part of the stopping mechanism to bring the sewing shaft to rest in time. If careful adjustments are made in the driving and stopping mechanisms, these results may be obviated but such adjustments are difficult to effect, particularly where access is limited by the use of a completely enclosing casing strucfrequent adjustments of the driving and stopping mechanism in the present sewing machine, means are provided for preventing the high speed driving mechanism from being thrown out of op eration until the main haft reaches substantially its normal stopping position, and preferably at all times during rotation of the mainsew'ing shaft, except just before the position of the main sewing shaft is reached where the low speed driving mechanism ordinarily begins to drive, the sewing shaft. The weight of the operating parts of the present machine has been substantially reduced through the use of modern materials and weight eliminatingconstruction so that under certain LII circumstances, if the treadle controlled member is co moved to a stopping position while the stitch forming devices engage the work,v the resistance ofiered by the work to the stitch forming devices may be suificient to bring the machine to rest out of proper stopping position. Accordingly, in the present formof this feature. of the invention, the means for preventing operation of thetreadle member is effective until the stitch forming devices are free of thework. As hereinafter described, the treadle member-is locked by a. latch in a position to cause the sewing shaft to be driven positively, and means actuated by the sewing shaft is provided to release the latch only while the stitch forming devices are. disengaged from the work. Thus the movements of parts will not be stopped by the resistance offered by the work before the stopping mechanism acts.

Other features of the invention include novel and improved constructions; arrangements, and combinations of parts, hereinafter described and claimed which, together with't'h'e advantages to be obtained thereby, will be readilyunderstood by those skilled in the art from the following descriptiontaken in connection with the accompanying drawings; I

In the drawings, Fig.1 is a side view of amachine embodying the present invention,1o'o'king from the right of the machine, with the right end plate of the casing removed; Fig. 2'is a front view on an enlarged scale of the housing head of the machine, the casing being removed and end portions of the frame brokena'way; Fig.- 3 is a plan view on a similar scale, with the casing shown 7 in section; Figjiis a sectional viewof the sewing head with the right end plate removed; Fig. 5 is a right-hand side sectional view of the parts at the front of the sewing head of the machine, as viewed'along the line 5+5 ofFig. 3; ,Fig. 6 is a sectional view of the sewinghead taken along the line 6-6"of"Fig. 2;'.'and Fig. '7 is a detail of some of the parts indicatedin Fig. 5,".as viewed fromthe opposite side of themachine.

The illustrated machine is a Jockstitch outsole shoe sewing machine ofthefsamegeneral con-.- struction and mode of operation as that disclosed in U. S. Letters Patents'tofl lrench and iMeyer; No. 473,870, of April26, 1 892jand pro-vided with stitch forming devices "actuated by means of a single. main sewing shaft rotated fbyi a; power driven belt engaging apulley on the shaft. The machine is fully illustrated and described in applicant s United States Letters Patent ,No. 2,328,- 011, for Shoe sewing machinespgrantedAugust 31, 1943, on applicant's co pending application Ser. No. 294,926, filedSeptember'14, 1939,-anq of which the present application is'a division. The

ries a pulley which is engaged by a low speed driving belt 10 which passes over a driven pulley I4 carried by a worm shaft 16 engaging a worm wheel I8 loose on the main sewing shaft. The

low speed stopping mechanism is similar to that disclosed in U. S. Letters Patent to Topham No. 1,099,328, dated June 9, 1914. r i

As has been stated, the high speed driving mechanism for the present machine is held from being thrown out of operation until the main sewing shaft 2 reaches substantially its normal stopping position- Toengage the driving pulley 68 of the high speed driving clutch with the driven part of the clutch indicated at I42 in Fig. 2, the pulley 68 is acted'upon by the upper forward end" of a lever-I44 fulcru'med 'on a pin I46 secured inthe frame of'the machine. The lower-arm of the lever I44 is connected by a pair of toggle links I48 and. I50'with the enlarged head of a bolt I52 slidingly mountedwithin a lug portion of the machine frame. The central joint of the toggle links is connected to the upper endof a control rod I54, the lower end of which is-con nected to an arm I56" secured to a shaft I58 also carrying a foot treadle I60 extending forwardly of the machine through an opening in the cover structure. when the treadle-rod I54 is depressed, the lever I44 moves the clutchmembers 68,142 into vengagement and at the same time the link I50 which is squared at one endmoves beneath a latch lever I62 which looks the toggle linksin substantial alignment until released. To cause the latch lever I62 to lock the link I50, the lever is connected by a spring I64 stretched between the lever and a pin on the machine frame and, when the machine is in stopped position, the lower end of the lever is held in inoperative position by the squared end of the link I50. By locking the toggle links I48, I50 in aligned position,

the control rod I54 and treadle I60 are at the same time held depressed so that the sewing shaft is driven at high speed and the low speed stopping mechanism is held from operation until such time as the toggle link I50 is released by the latch lever. To release the link I50 from the latch lever I62, the upper end of the lever carries a roll I61 arranged to be engaged by a cam I66 on the driven clutch member I42. To render the action of the high speed clutch in starting the machine less abrupt. and to prevent application of excessive pressures between the members of the clutch, the shank of the bolt I52 is surrounded by a spring I68 acting between the head of the bolt and an adjusting sleeve "0 threaded in the lug which supports the bolt.

The high speed driving mechanism of the present machine is held operative, and the low speed stopping mechanism is not operated to bring the sewing shaft to rest until after the needle and awl have become disengaged from the work in any sewing cycle. The resistance offered I by the needle and awl while engaging or penetrating the work, particularly with thick work,.is the greatest offered by anyof the stitch forming devices during each sewing cycle and, since the resistance may vary with different qualitiesof work if the high speed driving mechanism becomes inoperative during the engagement of the needle and awl with the work, the sewing shaft may come to rest at an irregular stopped position. To insure that the sewing shaft will be driven positively while the needle and awl are engaging the work, the link I50 and control rod I54 are not released by the latch lever I62 until after the needle and awl are disengaged and just before that part of the rotation of the sewing shaft where the low speed stopping mechanism becomes effective. The release of link I50 and control rod 454 occurs in the present machine directly after the middle of each sewing cycle, leaving approximately a half of the sewing cycle to slow down and bring the sewing shaft to rest.

As in the low speed stopping mechanism of the Topham patent above referred to, the machine is driven at low speed by a low speed driving clutch actuated by means of a vibrating lever having an opening which is engaged by a lock bolt after the operator removes his foot from the control treadle. In the present machine, the low "speed driving clutch comprises the worm wheel I8, a driven clutch member I60 splined to a sleeve I82 secured to the sewing shaft 2- and forming a bearing for the worm wheel I8. The driven clutch member I is normally held out of engagement with the worm wheel by means of compression springs, one of which is indicated at I84 surrounding studs secured to lugs formed on the driven clutch member I80 and slidable in sleeves I86 mounted in similar lugs formed on sleeve I82. The hub of the driven clutch member has a cam groove I88 for actuating a vibratinglever I90-(see Fig; 3); During sewingoperations, the driven clutch member I80 rotates with the sewing shaft and causes the lever I90 to oscillate once during each sewing cycle and, when the-high speed driving clutch is thrown out of operation, the lock bolt, shown in Fig. 5 at I 92, slides vertically in a carrier I94 into an opening in the vibrating lever I90 holding the lever stationary. The cam groove I88 is so shaped that during the continued rotation of the sewing shaft, the driven clutch member 500 engages the worm wheel 18 briefly to slow down the I sewing shaft and thereafter moves away from the worm' wheel to permit the sewing shaft to come to a uniform position of rest. When the machine is again started, the lock bolt is withdrawn from the vibrating lever by connections with the treadle I60 including a treadle. rod I06, a pivoted cam arm I98 (see Fig. 7) and a cam follower lever 200 having a roll 204 and an'arm connected by means of a link 206 with the lock bolt; When the'latch lever I62 locks the high speed clutch-iii driving engagement, it also prevents movement of the treadle and of lock bolt against the vibrate ing lever I90, thus holding the low speed stopping mechanism from operation. The timed relation between the cam I 66 of the high'speed clutlch and the cam slot I 88 of the low speed stopping niecha; nism is such that the lock bolt may notengagethe vibrating lever until after the opening in thelever is in alignment with the lock bolt and just before the active part of cam slot I88 is .teat'heaith alignment of the lever with the lock boltocixr-Q ring only while the stitch forming devicesengage thework and-for a short interval thereafter.

After the time in any sewing cycle-when the lock bolt may engage the opening in the vibrating lever, the cam I66 allows the latch leyer1l62 to move under the influence of the springiI64'in a direction to lock the link I50and'the control rod I54 against upward movementso that if the low speed driving mechanismhas not been rendered operative by this time, it will again beheld inoperative until the next sewing cycle.

The stitch forming devices of the machine include the curved hook needle and curved awl indicated at 208 and 210, respectively, an oscillat ing loop taker or shuttle H2 in which is rotatably mounted a thread case 214, main and auxiliary take-ups 2I6 and 2l8, a looper 220, a thread lifter 222, a thread clamp or lock lever 224, a tension 225, and other devices cooperating to form a lockstitch seam. The work is clamped in stationary relation to the stitch forming devices by a work support 226 and a presser foot 228 mounted on a. presser foot lever 229, the work being fed while released fromthe clamping action of the presser foot by lateral movements of the awl, as in the machine of Patent No. 473,870. The stitch forming devices are actuated by suitable driving connections from the sewing shaft 2 to which there is secured a series of cams 230 shaped similar to the cams of the Patent No. 473,870 referred to, and composed of synthetic resinous material, as in present inven-. tors prior .U. S. Letters Patent No. 2,037,722, of April 21, 1936. To assist further in bringing the machine to rest with the stitch forming devices uniformly in stopping positions, one of the cams 230 has a notch 232 along its periphery arranged to be engaged by a hook member 234 pivoted on a screw stud 236 threaded in the machine. During normal sewing operations, the hook member 234 is held free ofthe cam which has the notch 232, the hook member being brought yieldingly into engagement with the periphery of the cam just before the stopping position is reached.

, The thread lock lever224 is similar to that disclosed in Patent No. 473,870 andis actuated to clamp and release the needle thread as it passes over a thread guiding pulley 238 in timed relation to .the motions of the other stitch forming devices. The lock lever is fulcrumed on a stud 240 and has one arm engaging a notch in the hub of an arm 242. Pivotally connected with the am 242 is one of a pair of toggle links 244 and 246, the other one of which is pivotally connected to a cam actuated lever 248 fulcrumed on the stud 236. During normal sewing operations, the toggle links 244 and 246 are, held in alignment so as to transmit the motion of the cam lever to the thread lock. The movements of the cam lever 24B are such that when the sewing shaft passes through stopping position, the thread lock is closed. To permit needle thread to be drawn freely from the machine when in stopping position, normally inoperative mechanism actuated by the cam lever 248 is provided which when rendered operative, breaks the alignment of the toggle links 244, 246.

The mechanism for breaking the alignment of th toggle links 244, 246 to release the thread from clamping engagement of the lock lever 224 also causes the hook member 234 to be moved yieldingly against-the cam 230 and comprises a link 250 pivotally connected between the upper end of the cam lever 248 and an oscillating yoke 260, as best shown in Figs. 3 and 5. The yoke 260 is rotatably mounted on a rock shaft 262 supported in bearings 284 at the rear of the machine. During sewing operations, th yoke 26.0 is oscillated idly by the cam lever 248 and, when the latch lever I62 releases link I50 and the control rod I54, a latch arm 268 carried by one arm of a lever 270 swings into the path of movement of an arm on the oscillating yoke 260, causing the lever 270 to be actuated. When the lever 270 is moved, connections including a link 272 connected to the lever 270 and a lever 274 fulcrumed on a fixed stud screw 276 cause the alignment of the toggle links 244 and 246 to be broken so that the thread lock 224 is held open. The lever 274 is also connected with the hook member 234 through a link 278 bymeans of a pin 280 which passes through the central joint of the toggle links, a horizontal slot in one arm of the lever 274 and the link 278. A vertically slotted connection is provided between the link 278 and the hook member 234 so that if the connections thus described are actuated before the notch 232 on the cam 230 reaches a position opposite the hooked end of the hook member, no damage will result, the hook member being yieldingly urged against the periphery of the cam by a spring 282 stretched between an arm of the hook member and a stationary guide of the machine. The connections for unlocking and raising the presser foot from the work at the end of a seam include the rock shaft 262 on which is secured the lever 270, an arm 284 (see Figs. 4 and 6) loose on the rock shaft 262, a link 286 pivotally connected at its rearward end with the arm 284 and sliding loosely at its forward end in a perforated plate portion of a presser foot unlocking lever 288. The unlocking lever 288 is loosely mounted on the presser foot fulcrum pin 290, and is engaged by a check nut 287 on the rod 286 to release a pair of locking pawls 292 and 294 of the presser foot actuating mechanism in a manner similar to that disclosed in the 11. 8. Letters Patent to Topham, No. 1,289,312, of December 31, 1918. Upon continued movementof the, rock shaft 262,. a slotted arm 296 loose on the shaft 262 ,is engaged within its slot by a pin 29'! on a lever 298 fast to the shaft, the slotted lever 296 having connected to it a link 300 and a lever 302. The lever 302 is mounted onafixed pivot 304 and overlies at its forward end the upper portion of a harp-shaped frame 306 (Fig. 6) similar to that described in Patent No. 473,870, which frame, as explained in said patent, is directly connected with the presser foot. Through the connections thus described, the presser foot is raised from the work after being unlocked,

To prevent continued movement of the presser foot unlocking connections after being actuated to unlock the presser foot, the arm 284 is operated by the lever 298 through a ball lock connection. The arm 284 rides between a plate-like arm of the lever 298 and a fixed plate 308 secured to the bearing 264. A recess is provided in the plate-like arm of the lever 298 to receive a ball 3l0 sliding loosely through an opening in the arm 284, the plate 308 holding the ball partially within the recess of the lever 298 during sewing operations and, when the rock shaft is actuated, the arm 284 moves with the lever until the ball 3l0 lines up with a recess 3I2 (seeFig. 3) in the plate 308. The ball 3l0 then slides out of the recess in the lever 298 and into the recess 3I2, locking the arm 284 to the plate 308 during continued movement of the lever 298. To actuate the latch member 268 towards and from latching relation with the arm of the oscillating yoke 260, the latch member is secured to one end of a pivot pin 3l4 loosely mounted in an arm of the sleeve 270. The other end of the pivot pin 3|4 carries an arm 316 having a stud 3! between which and a pin 320 on the lever 270 there is stretched a spring 322 tending to hold the latch member. inilatchingposition; When the treadle rod is depressed'to start thema'chine, the latch member 268 is moved to inoperative position by an S-shaped arm 324 (see Fig. 7) pivoted concentrically-with the cam arm I98 and connected thereto through a pin and slot connection. The free end of the arm- 324. overlies the pin 3l8 so that when the arm 324 is moved downwardly as the treadle rod is depressed, the latch member 268 is rocked out of engagement with the arm of the yoke 28!). As soon as the latch member is rendered inoperative, a tension spring 326 connected between an arm 328 secured to the shaft 262 and a fixed part of the frame rocks theshaft 262 to cause the presser foot and stitch forming devices to operate in theusual way.

In order to stop the machine with the last loop of needle thread partially projecting from the upper surfaces ofthe work so that both threads may be severed closeto the upper surface of the work by a single'stroke of a hand knife, the driving and stopping mechanism including the cam having the notch 232 and the hook member 234 is so arranged that the machine will come to rest before the awl enters the work for a new stitch and after the needle loop pulls the loop of needle thread from the loop taker almost to the surface of the work. The stitch setting movement of the take-up occurs after the high speed driving mechanism has been rendered inoperative and while the sewing shaft is being driven at low speed. Also during this time, the presser foot'is being lifted by the normally inoperative mechanism so that the power absorbed by these operations is provided by the low speed mechanism. I

The nature and scope of the invention having been indicated and a particular embodiment of the invention having been described, what is claimed is:

1. A driving and stopping mechanism having, in combination, a main shaft, high and low speed mechanisms for driving said shaft, a treadle actuated control member for throwing the high speed driving mechanism into and out of operation, normally inoperative'means rendered operative when the high'speed mechanism is thrown out of operation to causethe low speed mechanism to drive said shaft through a predetermined part of a rotation and then to cause the shaft to come to rest, and means acting during each rotation of the main shaft to prevent the high speed driving mechanism from being thrown out of operation except when the main shaft is in substantially normal stopping position.

2. A driving and stopping mechanism having, in combination, a main shaft, high and low speed driving mechanisms for driving said shaft, a treadle actuated control member for rendering the high speed driving mechanism operative or inoperative, normally inoperative means driven by the main shaft for causing the low speed mechanism to drive the shaft through a predetermined movement and then to permit said shaft to come to rest when the high speed mechanism is thrown out of operation, and means for locking the control member from actuation except just before that part of a rotation of the main shaft where the low speed mechanism is caused to drive the main shaft.

3. A driving and stopping mechanismhaving, in combination, a main shaft, driving and stopping mechanisms including a vibrating lever actuatedby the shaft, a lock bolt forengaging' the lever, to bring: theshaft torest in apredetermined position, a treadle actuated control mem -n. her for withdrawing the lock bolt from the,vi-

brating lever and for throwing the driving mech-. anism into operation when moved in one direction and forreleasing the lock bolt to cause its engagement with the vibrating lever when moved in the other direction, and means acting during each rotation of the main shaft to lock the treadle except during that part of the rotation of the shaft where the vibrating lever is in posi tion to beengaged with the lock bolt.

4. A .driving and stopping mechanism having, in combination, a main shaft, a vibrating lever having an opening actuated by the shaft, a lock bolt for engaging thelever to bring the shaftato. rest'in apredetermined position, a treadleactuatedcontrol member. forv withdrawing the lock; bolt from the vibrating lever and for throwing the driving mechanism into operation whenmoved in one direction and for releasing the lock bolt to cause it's engagement with the vibrating lever when moved in the other direction, a latch forlockingthe treadle against movement in a. direction to cause the lock bolt to engage the lever, and means for releasing the latchfrom the treadle member when the vibrating lever. is in a position to be engaged by the lock bolt.

5. A driving and stopping mechanism having, in combination, a main shaft, a vibrating lever having an opening actuated by the shaft, a lock bolt for engaging the opening in the lever to bring the shaft to rest in a predetermined position, a treadle actuated control member for withdrawing the lock bolt from the vibrating lever and for throwing the driving mechanism into operation whenmoved in one direction and for, releasing the lock -bolt to cause its engagement with the vibrating lever when moved in the other direction, a latch for locking the treadle against movement in a direction to cause the lock bolt to engage the lever, and a cam driven from ,the main shaft for actuating the latch to release the treadle member when the opening in the vibrating lever is ina position to receive the lock bolt.

6. A shoe sewing machine having, in combination, a main sewing shaft, stitch forming devices actuated thereby, driving and stopping mechanism for bringing said shaft to rest at'the end of a seam,.a treadle actuated control member'for the driving and stopping mechanism ar ranged when actuated in one direction to cause the shaft to be driven and in the other direction to cause the shaft to be brought to rest, and means acting during each rotation of the main shaft to prevent movement of the treadle control member in a direction to cause the shaft to be brought to rest in any sewing cycle until after the stitch forming devices are free of the work;

'7. A shoe sewing machine having, in combination, a main sewing shaft, stitch forming devices actuated thereby, driving and stopping mechanism for bringing said shaft to rest at the end of a seam, a treadle actuated control memher for the driving and stopping mechanism ar ranged when actuated in one direction to cause the shaft to be driven and in the other direction to cause the shaft to be brought to rest, and means acting during each rotation of the main shaft to lock the treadle control member during each sewing cycle in a position to cause the sew ing shaft to be driven until the stitch forming devices are free of the work.

8. A shoe; sewing machine having, in combination, amain' sewing shaft, stitch forming de- 1 operative or vices including a needle actuated thereby, driving and stopping'mechanism for bringing said shaft 'to rest at the end of a seam with the stitch forming devices free of the work, a treadle actuated control member for "the driving and stopping 'mechanism arranged when actuated in one direction to cause the shaft to be driven and in the other direction to cause the shaft to be brought to rest, a latch" for locking the treadle member in a position to cause the sewing shaft to be driven, and means actuated by the sewing shaft to release the latch from the treadle member during'each sewing cycle while the needle is disengaged from the work.

9. A shoe sewing machine having, in combination, a main sewing shaft, stitch forming devices actuated thereby including a needle and an awl, a driving and stopping mechanism having high'and low speed mechanisms for driving the sewing shaft, a treadle actuated control member for rendering the high speed driving mechanism operative, or imperative, and normally inoperativemeans acting when the high speed mechanism is thrown out of operation and only during that part of asewing cycle where the needle and awl are disengaged from the work to cause the low speed driving mechanism to drive said shaft through a predetermined movement andthento permit the shaftto come to rest.

10. Ashoe sewing machine having, in combination, a main sewingshaft, stitch forming devices actuated thereby including a needle and an awl, a driving and stopping mechanism having high and low speed mechanisms for driving the sewing shaft, a treadle actuated control member for rendering the high speed driving mechanism inoperative, normal inoperative means driven by the sewing shaft for causing thelow speed mechanism to drive said shaft when the high speed mechanism isthrown out of operation and after the needle disengages the work, and then to permit the shaft to come to rest before the'awl enters the work, and means for preventing the high speed mechanism from being rendered inoperative in each sewing cycle until after the needle is disengaged from the work.

11. A shoe sewing machine having, in combination, a main sewingshaft, stitch forming devices actuated thereby in cluding a needle, an

awl, a loop taker and a take-up for pulling each loop of needle thread from the loop taker and for setting the stitches, drivingand stopping mechanism having high and low speed'mecha nisms' for driving the sewing shaft, a treadle actuated control member for rendering the high speed driving mechanism operative or inoperative, and normally inoperative means acting when the high speed mechanism is thrown out of operation and before the awl enters the work to cause the low speed mechanism to drive said shaft and then to permit the shaft to come to rest after the take-up pulls the needle loop from the loop taker and before the take-up acts to set the final stitch of a seam.

12. A shoe sewing machine having, in combination, a main sewing shaft, stitch forming devices actuated thereby including a needle, an awl, a loop taker and a take-up for pulling each loop of needle thread from the loop taker and for setting the stitches, driving and stopping mechanism having high and low speed mechanisms for driving the sewing shaft, a treadle actuated control member for rendering the high speed driving mechanism operative or inoperative, normally inoperative means acting when the high speed "mechanism is thrown out of operation and before the awl enters the work to cause the low speed mechanismto drive said shaft and then to permit the shaft to come to rest after the take-up pulls the needle loop from the loop taker and before the take-.up acts to set the final stitch of a seam, and means for preventing the high sped driving" mechanism from being rendered inoperative in each sewing cycle until the needle is disengaged from the work and before the takeup pulls the needle loop from the loop taker. I 13. A'shoe sewing machine having, in combination, a main sewing shaft, stitch forming de vices actuated thereby including a needle, an awl,

a loop taker and a take-up for pulling each loop of needle thread from the loop taker and for setting the stitches, driving and stopping mechanism having high and low speed mechanisms for driving the sewing shaft, a treadle actuated control member for renderingthe high speed driving mechanism operative or inoperative, normally inoperative means acting when the high speed mechanism is thrown out of operation and before the awl enters'the work to cause the=low speed mechanism to drive said shaft and then to permit the shaft-to come to rest after the take-up pulls the needle loop from the loop taker and before the take-up'acts to set the final stitch of a seam, alatch for holding the treadle member in a position Where the high speed driving mechanism is operative, and a cam on the sewing shaft for releasing the latch from the control member in each sewing. cycle while the needle is being disengaged from the work. r :14. A shoesewing machine having, in combination, a main sewing shaft, stitch forming de- "vices actuated thereby, and driving mechanism for the sewing. shaft including a driving clutch member, a driven clutch member,'a pair of toggle links arranged atone end to press the clutch members together, a treadle. connected to the middle joint of the pairand a spring connected at the other end of said pair of toggle links to prevent the exertion of excess pressures of the links on the clutch members.

' 15. A sewing machine having, in combination, a main sewing shaft, stitch forming devices, driving and stopping mechanism having a vibrating lever and a lock bolt for'engaging the vibrating lever to bring the sewing shaft to rest at the end of a seam with the stitch forming devices free of the work, a treadle actuated control member for ywithdrawing the lockbolt from the vibrating lever ancl-for causing'the sewing shaft to be started ;when actuated in one'direction and for releasing the lockbolt to permit its engagement with the vibrating lever when actuated in the other direction, the vibrating lever-being held in alignment to receive the .lockzbolt while the stitch forming V devices engage the work and for a short interval thereafter, and means acting during each rotation of the main shaft to prevent the lock bolt from'engaging the vibrating lever while the stitch the lock bolt to permit its engagement with the vibrating lever when actuated in the other direction, the vibrating lever being held in alignment to receive the lock bolt while the stitch forming devices engage the work and for a short interval thereafter, a latch for locking the treadle actuated member from movement in a direction to release the'lock bolt, and a cam on the sewing shaft for releasing the latch for a short interval only while the stitch forming devices are free of the work.

17. A sewing machine having, in combination, a main sewing shaft, stitch forming devices actuated thereby, a presser foot, a driving and stopping mechanism for the sewing shaft having high and low speed mechanisms for driving the sewing shaft, atreadle actuated control member for throwing the high speed mechanism into and out of operation, normally inoperative means rendered operative when the high speed mechanism is thrown out of operation to cause the low speed mechanism to drive said shaft through a predetermined part of a rotation and to bring the sewing shaft to rest at the end of a seam with the stitch forming devices free of the work, an

oscillating part actuated by the sewing shaft, a latch for connecting the oscillating part and the resser foot when the driving and stopping mechanism is thrown into operation to lift the presser foot as the sewing shaft comes to rest, and means connected to the treadle actuated member for holding the latch out of latching position during sewing operations.

18. A sewing machine having, in combination, a main sewing shaft, stitch forming devices actuated thereby, a presser foot, a driving and stopping mechanism for the sewing shaft having high and low speed mechanisms, a treadle actuated control member for throwing the high speed mechanism into and out of operation, normally inoperative means rendered operative when the high speed mechanism is thrown out of operation to cause the low speed mechanism to drive the sewing shaft and to bring the shaft to rest at the end of a seam with the stitch forming devices free of the work, an oscillating part actuated continuously by the sewing shaft, and a latch for connecting the oscillating part and the presser foot when the low speed mechanism is thrown into operation to lift the presser foot as the sewing shaft comes to rest.

19. A sewing machine having, in combination, a main sewing shaft, stitch forming devices including a sewing thread look, a presser foot, a

lever oscillated by the sewing shaft to open and,

close the thread lock during each sewing cycle, driving and stopping mechanism having a vibrating lever and a lock bolt received by the lever to bring the sewing shaft to rest at the end of a seam with the stitch forming devices free of the work, a treadle actuated control member for withdrawing the lock bolt from the vibrating lever and for causing the sewing shaft tobe driven when actuated in one direction, and

for releasing the lock bolt to cause its engagement with the vibrating lever when actuated in the other direction, means actuated by the thread lock lever arranged when the treadle actuated member releases the lock bolt to prevent the thread look from closing during the final movement of the sewing shaft, and means for locking the treadle member from movement out of a driving position, except during that part of a rotation of the sewing shaft when the vibrating lever is in position to receive the lock bolt.

20. A sewing machine having, in combination, a main sewing shaft, stitch forming devices including a sewing thread look, a lever oscillated by the sewing shaft to open and close the thread lock during each sewing cycle, driving and stopping mechanism, a treadle actuated controlmember for causing the sewing shaft to be started and for rendering the driving and stoppin mechanism operative to bring the sewing shaft to rest at the end of a seam with the stitch forming devices free of the work and with the thread lock lever in a thread locking position, and' means actuated by the thread lock lever arranged when the driving and stopping mechanism is thrown into operation to prevent the thread lock fromlocking the thread during final movements of the sewing shaft.

21. A shoe sewing machine having, incombination, a main sewing shaft, stitch forming devices including a thread lock, a lever oscillated by the sewing shaft, a toggle connected between the thread lock and the lever to cause the thread lock to be closed and openedduring each sewing cycle, driving and stopping mechanism, a treadle actuated control member for causing the sewing shaft to be started and for throwing the driving and stopping mechanism into operation to bring the sewing shaft to rest at the end of a seamwith-the stitch forming devices free of the work, and means under the control of the treadle member for breaking the toggle before the sewingshaft is brought to restto'prevent the thread look from being closed during the last sewing cycle. a

22. A shoe sewing machine having, in combination, a main sewing shaft, stitch forming devices including a thread look, a lever oscillated by the sewing shaft, a toggle connected between the thread lock and the lever to cause the thread lock to be closed and opened during each sewing cycle, driving and stopping mechanism, a treadle actuated control member for *causing the sewing shaft to be started and for throwing the driving and stopping mechanism into operation to bring the sewing shaft to rest at the end of a seam with the stitch forming devices free of the work, and connections between the thread lock lever and the toggle comprising a latch controlled by-the treadle member for breaking the toggle before the sewing shaft is brought to rest to prevent the thread look from being closed during the last sewing cycle.

o'rro R. HAAs,

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