US2352274A - Sewing machine - Google Patents

Description

June 27, 1 944.

B. T. LEVEQUE SEWING MACHINE Filed June 17 1941 14 Sheets-Sheet l June 27, 1944.

B. T. YLE VEQUE SEWING MACHINE Filed Jun 17, 1941 14 Sheets-Sheet 2 June 27, 1944. B. T. LEVEQUE 2,352,274

SEWING MACHINE Filed June 17, 1941 14 Sheets-Sheet 3 June 27, 1944. B. T. .LEVEQUE 2,352,274

SEWING MACHINE Filed June 17, 1941 l4 Sheets-Sheet 4 ZZZ June 27, 1944. LEVEQUE 2,352,274

' SEWING MACHINE Filed June 17, 1941 14 Sheets- Sheet 5 June 1944- Y B. T. LEVEQUE ,35

SEWING MACHINE Filed June 17, 1941 14 Sheets-Sheet 7 Jime 27, 1944. B. 1-. LEVEQUE SEWING MACHINE Filed June 1'7, 1941 14 Sheets-Sheet 8 June 27, 1944.

B. T. LEVEQUE 2,352,274

SEWING MACHINE Filed June 17, 1941: 14 Sheets-Sheet 9 B. T. LEVEQUE SEWING MACHINE June 27, 1944.

Filed June 17, 1941 14 SheetsSbeet 10 June 27, 1944. B. T. LEVEQ UE 2,352,274

SEWING MACHINE Filed June 1'7, 1941 14 Sheets-Sheet ll June 27, 1944. B. T. LEVEQUE 2,352,274

. SEWING, MACHINE Filed June 17, 1941 l4 Sheets-Sheet 12 June 27, 1944. B T, LEVE UE 2,352,274

SEWING MACHINE Filed June 1'7, 1941 14 Sheets-Sheet 13 B. T. LEVEQUE SEWING 1311110111113 June '2 7, 1944.

Filed June 17. 1941 14 Sheet S -Sheet 14 Pet ented June 2%, l I v UNITED STATES] P TENT 2,352,274' SEWI G MACHINE Bernard T..Deveque, Wenham. Mesa, assignor to United Shoe Machinery rporation, Flemington, N. 1., a-eorporation of New Jersey Application m 194 1, Serial s ceases s's Claims (l.1123 4)' The present invention relates to machines for ity of the machine in quality of work performed sewing shoes or other articles composed of still," or ln'amount of skill ,or effort required on the heavy materials, and is hereinafter illustrated partof the operator.

as embodied in a shoe sewing machine of the A still further object is to provlde'a novel and straight hook needle type disclosedsin U. S.-Let- 1 improved driving and stoppin mechanism for I 'ters Patent to Merrick Nos. $90,854 to 490,857 insewing machines, theuse of which renders posslclusive,-'dated-January 31, 1893. ble simple and effective actuating mechanisms 'The machine of these patents is a chainstitch for the needle and awl, which mechanisms here sewing machine having an awl arranged to penetofore have caused amachine so equipped to be trate the work from above and form a perforascapable of competingrwith other machines only tion for a straight needle entering the perfora under a definite handicapso far as removal or tlon from beneath the work as the awl withdraws. substitution of workis concerned. n

e nee e. after entering the awl perforation, with these and otherobiects in view, afeature carries the work out of line with the awl the of, the present invention contemplates the provl-t length ofa stitchpreparatory to'the formation of l5 sion in a shoe s'ewingim hine having mecha-. a new awi perforation, thus imparting a feed n nlsms driven from a sewing shaft for actuating movement to the work. In the form'described the needle and-awl comprising an element movin the patents, that machine is effective even in able to disconnect-either the needle 'or awl from comparison with more modern machines at the the sewings'haft during the final sewing cycle of present date for sewing a satisfactory seam when a machine to-cause' the disconnected instrument carefully and expertly adjusted, but mechanical to'come to rest out of engagement with the work limitations to which the p tented ma hin i t as the other instrument continues its movements iect, render its'usediiliculhdue to frequent delays to complete the sewing cycle. This feature enrequired in maintaining the condition of proper ables the needle to'iie' withdrawn from engageadjustment, particularly when being operated ment with the work while the awl remains sta- '.at high speeds. The needle and awl of that tionaryvin' its stopping position also out of enmachine are driven from amain sewing shaft 'gagement with the work. Disconnection of the through simple 1 and mechanically advantageous awl from the sewing shaft is particularly. advanmechanisms including crank actuated connectageous in a sewing machine in which boththe tions, the needle being actuated when entering aoneedle andawl are-driven from crank actuated the work to follow the awl closely, thus insuring mechanisms vand follow each other closely durproper alignment of the needle with the awl 'per ing each sewing cycle because the needie and awl foration. With crank actuated needle and awl mechanisms may, .as a result, be adjusted for mechanisms arranged in this way, the speed and sewing without changing the distance between accuracy of sewing operations are sufll'cient- .for 5 th e'needle'and awl when themachine isllrollghtmany present day sewing requirements, but since p to rest.- Thus: when unusually thick work isboth the needle and am must be free-of the work I being operated upon, no dlfllculty is encountered I when the work-is withdrawn from the machine during sewing due to the necessity ofincreasing at the end of a seam or when new work is being the distance between the needle and awl required substituted, it frequently is'difllcult with thick 40 for removal of the work Preferably, means are heavy work to'make-proper sewing adjustments provided for bringing the needle to rest out of in the patented machine which will' not workito "engagement with the work after the awl has a disadvantage'so far as easy removal or substireached its stopping position. In this form of tution of the work in' the machine is concerned. the invention, the needle mechanism also is'pl'o- The objects of the presenti n i are, to vided with a disconnecting eleme tand control pr d a s o sewins' nschi e f s mp ified of both needle'and awl disconnecting elements is struction and improvedmode of-operation for effected layy members driven from the sewing doing the same type of work heretofore per-1; shaft, I v

formed with the machine of the Merrick patents- This feature of the invention also includes the work at'the end of a seam.

referred to-above and. which will more easily be master timing means for causing actuation of adjusted both for effective high speed sewing the disconnecting elements in the proper seconditions,as well as-for convenient. removal of. quence d l the final sewing cycle, the control v v members in the illustrated construction actingin Other objects are to provide a machine for this substantially the same timed relation 'when the ty e of work in which difiiculties inherent in the sewing operations are being started as when .patented. machine including those d' iiiculties- "stopped. To insure that the needle and awl above enumerated are avoided and which may beare retained in stopping positions. according to cneratedsuccessfully at sewing sneedsh gherthan vthis feature of the.invention,.the needle and awl heretofore considered possible with the patented are looked. after being disconn ted from the;

machine, without danger of sacrifice in dw 'f sewing shaft-at the enckof' aseam, and are un- The machine hereinafter described is also pro-- vided with a novel thread cutter and simplified and improved means for controlling the thread and also an improved form of presser foot lock. In addition to these features, the invention is embodied in certain constructions, combinations and arrangements of parts hereinafter described and claimed, the advantages of which will be apparent to those skilled'in the art from the following description.

Referring to the drawings, Fig. 1 is a view in side elevation, looking from the right of the machine, embodying the features of the present invention; Fig. 2 is a view in front elevation of the machine illustrated in Fig. 1 on a slightly enlarged scale; Fig. 3 is a cross-sectional view on a further enlarged scale, broken out to reduce the lengthwise dimension, and taken along a horizontal plane indicated by-the line 3-3 of Fig. I; Fig. 4 is a view in front elevation, partly broken away and in section of the machine illustrated in Fig. 1; Fig. 5 is a view in front elevation of the upper portion of the machine, a front cover having been broken away to illustrate the awl and presser foot lock actuating mechanism, with the parts indicated in positionsassumed when the machine is brought to rest and the presser .foot lifted; Fig. 6 is a View in front elevation of the presser foot lock actuating mechanism taken during sewin 'operations while the presser foot is locked in engagement with the work; Fig. 7 is a sectional view taken along the line of Fig. 6; Fig. 8 is a side sectional view taken along the line 8-8 of Fig. 5; Fig. 9 is a sectional plan view of the looper and tension devices taken along the line 9-9 of Fig. 8; Fig. 10 is a view in vertical section taken through the main sewing shaft of the machine at its rearward end, illustrating a portion of the driving and stopping mechanism with the parts in stopped positions; Fig. 11 is a view in front elevation of the lower portion of the machine, a cover plate having been broken away to illustrate the needle cast-off and thread cutter actuating mechanisms; Fig. 12 is a sectional view taken along the line iZ-IZ in Fig. 11; Fig. 13 is a sectional plan view taken along the line l3l3 of Fig. 12, showing the thread cutter after being actuated to sever the thread; Fig. 14 is another sectional plan view taken along the line I l-I4 of Fig. 12; Fig. 15 is a view in front elevation of the stitch forming devices illustrating the positions assumed just before the awl enters the work to form a perforation the awl has penetrated the work and the needle has withdrawn; Fig. 17 is a detail view on an enlarged scale of the needle cast-off illustrating the positions assumed with relation to the work, as indicated in Fig. 15; Fig. 18 is a similar view corresponding to the positions of Fig. 16; Fig. 19 is a view in front elevation of the stitch forming devices showing the needle as it begins to enter the work; Fig. 20 is a view of the same parts taken during work feeding movement of the for a new stitch; Fig. 16 isa view of the stitch forming devices just after 21 is a detail plan view indicating of looping the needle; Fig. 22 is a view in front elevation of the parts illustrated in Fig. 21; Fig. 23 is a detail view of the disconnectible connections in the awl actuating mechanism taken during sewing operations; Fig. 24 is a detail view in front elevation of the disconnectible connections for the needle actuating mechanism taken during sewing operations; Fig. 25 is a detail view of the awl actuating mechanism taken just after the connections are disconnected in stopping; Fig. 26 is a corresponding view of the awl actuating mechanism illustrating needle; Fig. the manner the positions of the parts during their continued movements; Fig. 27 is a detail view of the master timing disk and its follower, showing an intermediate position while passing through the slot in the disk; Fig. 28 is a detail view of the awl actuating mechanism illustrating the positions of the parts upon slight further movements of the sewing shaft from the position of Fig. 25; Fig. 29 is a detail view illustrating the corresponding positions oi the needle actuating mechanism; Fig. 30 is a detail view of the awl actuating mecha-' nism taken just before the presser foot is lifted from the work; Fig. 31 is a detail view of the needle actuating mechanism corresponding to the position of the awl actuating mechanism illustrated in Fig. 30 and showing the position of the parts just after the needle actuating connections are disconnected; Fig. 32 is a detail view of the followers for the needle control member, together with their control cams, illustrating the positions as the machine is being brought to rest; Fig. 33 is a similar view of the needle control followers and cams as the machine is being started; Fig. 34 is a detail view of the awl actuating mechanism'illustrating the position of the arts after the presser foot is lifted from engagement with the work; Fig. 35 is a corresponding detail view of the needle actuating mechanism; Fig. 36 is a detail view of the awl actuating mechanism illustrating the positions of the parts as the machine is being started in operation; Fig. .3? is a corresponding detail view of the needle actuating mechanism illustrating how the connections remain disconnected-until after the awl has penetrated the work; Fig. 38 is a detail view of the followers for the awl control member, together with their control cams illustrating the relative positions as the machine is being brought to rest; and Fig. 39 is a similar view of the awl control followers and cams illustrating their relative positions while starting sewing operations.

The sewing machine illustrated in the drawings is a chainstitch straight hook needle machine having an awl operating from above and the needle from below the work. A work feeding movement is imparted to the needle while engaging the work to advance the work a stitch length. The stitch forming devices of the machine aredriven from a main sewing shaft through cranks, pitmen and suitable connections between the stitch forming devices and the sew- Jing shaft, as in the machine of the Merrick patanisms, as disclosed above the work support the. work support with towards and from the the work adjacent the 22 driven from the main sewing shaft through a bevelgear train including gears 24, 28, a vertical shaft 28 and gears 30,12, all of which gears have the same number of teeth. 1

As in the above patents, the awl in the illustrated machine first penetrates the work in each sewing cycle and the needle follows the awl closely as the awl is being retracted from the work in order to insure that the needle will enter the per foi'aticn formed by the awl (see Fig. 19). To obtain this result with simple crank actuated mechin the patents, the needle and awl driving cranks are arranged on the sew-' ing shaft l8 and the auxiliary shaft 22 with an angular separation of approximately 180. In order that the work operated upon may be removed readily' in any sewing cycle in-which the stitch forming devices are brought to rest and to provide space for looping the needle, it is sometimes necessary to depart slightly from the 180" angular separation between the needle and awl cranks in favor of a greater spacing between the needle and the awl while the needle engages the work and the awl crank is arranged to provide a longer stroke than the needle crank. By so dolng, after the thread has been disengaged from the needle at the end of a seam, and the presser foot raised, the work may be removed without obstruction. Even with such provision for removing and replacing the work, when thick work such as is met in heavy shoe soles is being operated upon, it is necessary to adjust the positions I of the needle and awl in their respective holders .as far apart as possible consistent with practical sewing. However, to cause the needle to be projected sufficiently above the 'upper surface of the work and the looper to lay the thread with oertainty in the hook of the needle, under these conditions, the looper also must be adjusted to carry 'the thread close to the upper surface of the work and adjustments in others of the stitch forming devices are necessarywhen so adjusted, the machine is capable of operating successfully on thick work but not on thin work because the needle does not follow the awl sufliciently closely and by reason of other inaccuracies in timing, Under certain circumstances, particularly when the operating parts of the machine become ,worn, proper adjustment of the machine for different thicknesses of work becomes a practical impossibility and even under the best circumstances, proper adjustments when the thickness of the work is changed frequently result in 'loss of time and require special skill and ability on the part of the operator.

ing devices. As a result, operators of much less skill and experience may be employed than with the machine of the patent.

To enable the machineto sew relativel thick work without increasing the spacing between the needle and awl so that or replaced easily, the awl actuating mechanism has a train of connections between the crank It and the awl including an element movable to disconnect the awl from the sewing shaft during the last sewing cycle of the machine so that the needle may continue its movement and complete the stitch being formed and separate from the awl sufficiently to remove the work, The awl is brought to rest in a position at the end of its stroke most remote from the work and the needle continues its stitch forming movements it, in turn, withdraws from the work.

In order to insure that the needle remains in this position as the machine is brought to rest,

. the needle driving mechanism also is provided frame to which lever the with a train of connections having a disconnecting element acting after the needle has reached its stopping position. By arranging the needle and awl driving mechanisms in this way, the amount of angular separation between the needle and awl driving cranks is no longer a factor which determines the separation of the needle and awl in stopping and consequently, no adjustments are necessary for sewing relatively thick work.

The awl actuating mechanism comprises the pitman 34 (see Figs. 5 and 8), one end of which engages the crank IS, a driving lever 36 fulcrumed on a bolt 38 secured in the machine pitman 34 is connected, and an awl lever 40 also fulcrumed on the stud and connected through a. link 42 to a reciproeating awl bar 44. During sewing operations, the driving lever 38 is connected with the awl lever 40 and during the last sewing cycle of the machine, the levers are disconnected, the awl lever being locked in position with the awl bar 44 at the highest point in its reciprocating travel. To connect and disconnect the levers 36 and ill, a 'latch link 48 is mounted to swing on a pin it secured in the end of the lever 40 and arranged with its hooked portion to be engaged with or disengaged from a pin 50 secured in the end of the lever 36. when the lovers 36 and 40 are with each other (see Fig. i 52, H on the respective levers hold ;the levers from relative movement in one direction and the latch link 48 engaging the pin serted'in a perforation of The machine of the present invention is capable of being so adjusted that it will a wide range of work justment and when the work does require adjustments to be made, they may be completed with relatively few simple'changes and without requiring general realignment of the operating parts and stitch formoperate upon thicknesses without any adthe thickness or quality of 50 holds the levers from relative movement in the opposite direction. This is the condition for sewing operations and as a result, the movements imparted by the crank ii are transmitted into reciprocating movements of the awl supporting bar H. -To keep the latch link 46 in engagement with the pin 50, there is coiled about the pin 48 a spring 56 (see Fig. 8), having one end in- 7 an enlarged head on the .pin ti'on in thesewing operations, the latch link is disengaged from the'pin I and a slotted end of a locking arm}! is brought into surrounding relationship with the pin-A8 to lock the awl actuating lever 40 in stopped position-(see Fig. 25). Todisengage the latch link from the pin, ID on the lever Ii, the locking arm "carries a roll to 0pthe work may be removed until and the other end in a similar periora-' the side of the latch link. At the end of arms 98 particular position machine is provided with driving and stopping mechanisms having a latch controller member, as in the machine of present inventor's U. 8. Letters Patent No. 2,144,768 of January 24, 1939, and No. 2,283,073, of May 12, 1942, comprising a shaft 62 to which the locking arm 58 is secured, a stop arm 64 and a start arm 66 also secured to the control shaft 62. The stop and start control arms 64, 68 have cam rolls operated at certain times by stop and start cams 68 and rotating with, but slidable lengthwise of, the sewing shaft I8. When the stop cam is brought into alignment with the roll on the arm 84, as in Fig. 38, the awl is disconnected and when the start cam is brought into alignment with the roll on the arm '66, as in Fig. 39, the awl is again connected with the sewing shaft.

The needle actuating mechanism, best shown in Figs. 3, 11 and 12, is generally similar to the awl actuating mechanism. On the needle actuating crank 20 is a stud surrounded by one end of a pitman I2, the other end of which is connected by a driving lever 14 fulcrumed on a bolt I6 in the machine frame. The bolt I6 also supports a. needle actuating lever I8 connected through a link 80 to the lower end of a reciprocating needle bar 82. During sewing operations, the needle actuating lever II and the lever I4 move togetheras a unit, being connected by a latch link 84 arranged to swing on a pin 88 secured in the end of the needle actuating lever I8 towards and from a pin 88 at the end of the lever 14. link in engagement with the pin 88, the pin 86, is surrounded by a coil spring 90, one end .of which is inserted in a perforation in the enlarged head of the pin 82 andthe other end of which is insertedin a perforation in the side of the latch link.

The needle actuating latch link '84 is moved out of engagement with the pin 88 at the end of a seam by a locking arm 92 having its end suitably slotted to surround the pin 86 and provided with a roll 94 acting on the side of the latch link 84 to disengage it from the pin 28. The locking arm 92 is secured to one end of a shaft 96 forming together with stop and start and IN, a controller member for the needle actuating mechanism. The stop and start arms are made fast in spaced positions along the shaft 96 and are provided with cam rolls cooperating with stop and start-cams I02 and Ill rotating with, but slidable lengthwise of, the shaft 22. When the stop cam I02 is brought into alignment with the roll on the stop arm 92, as in Fig. 32, the needle is disconnected, and when the start cam I04 is brought into alignment with the roll on the arm I", the needle is again connected with the-sewing shaft. a 7

To hold the needle controller member in actuated position, a tog le spring ill (see Fig. 3), is stretched between a pin on the stop arm 08 and passes across the end of control shaft 20 to an eye bolt m secured in the frame of the machine. The hub of arm 88 also has-an open slot into which projects the end of a limit pin I01 secured in the machine 'frame to prevent movement of the controller member beyond the position to which it is actuated by the control cams.

As has'bee stated, provided to prevent start cams along the master timing means is movement of the stop and sewing shafts except at one of the sewing shaftso that/ the needle and awl controller members will a timing am on a lever in having a roll III II- To keep the hook portion of the latch yielding members. If

and 11) for raising the operator, an arm IIB secured to one end of a rock cured. The sleeve I24 is end to receive tongue-like portions of a collar I ranged to pass through the slot in the disk II. when the slot, is located opposite the roll and to be held from movement by the disk at other times. The lever I09 has an elongated hub rotatable on a shaft II2 which forms a portion of the treadle connections for actuating the control cams so that movements of the cams are prevented except when the timing disk and sewing shaft are in predetermined'positions. The angular location of the slot in the timing disk is so adjusted that the treadle connections may be actuated at a time suitable to cause the awl actuating mechanism to become operative before the needle actuating either in starting or stopping the machine.

The treadle actuated connections include a vertical treadle rod H4, a spring III (see Figs. 2 rod when released by the shaft H8 (Fig. 10) mounted in bearings on the machine frame, an arm of a lever I20 clamped to the shaft III inside the machine frame, and a link I22 pivotally connected at one end to the lever I20 forated block 124 rotatably mounted at the end of an arm extending from the elongated hub of the lever I69.- .Pivotally connected between the timing arm of lever I09 ands cam shifting arm I26 rotating on a stud In is a link I". The upper end of the arm I28 pivotally supports an arcuate shoe I22 fitting a circular track in a sleeve I24 on the shaft I2, awl stopping and starting cams '2, II are so slotted axially at one pinned to the sewing shaft II by means of which the cams 68, Ilare caused to rotate with the shaft while permitting sliding movement thereon. When the treadle rod I I4 is actuated, the connections thus described are shifted to bring either the stopping or starting cams selectively into alignment with their respective rolls, the timing arm roll'lll passing through the slotted portion of the disk I" as the cams are shifted.

The treadle connections are also provided with the movement of the timing arm roll 2 is held up by a solid portion of the disk, a pair of springs Ill and I4. on link I22 is compressed temporarily the disk registers with the stop I28 and I aresecured between the perforated block I24 and a pair of clamps I42 on the link I22.

The treadle connections for the needle stopping and starting control cams I02, I04 are actuated at the same time as the awl stopping and connections. However, the active portions of the needle control cams are displaced substantially The needle connections comprise a rod I44 pivoted at its upper end to a short arm on the lever Ill and at its lower end to one'arm of a bell crank I44 (see Fig. 4). fulcrumedon a stud I42 mechanism is operative and slidable at its other end in a perto which sleeve the until the slot in' roll. Thesprings from the'active portions of the owl contml' cams.

.ing this time, the

- the starting cycle.

aasaa'n secured to a bracket I88 on the machine frame. The bell crank I48 is .in turn connected through a link I82 with acam shifting arm III (see Figs. 3 and 12) fulcrumed on a stud I88 secured in the frame of the machine. The arm I88 supports at its free end an arcuate shoe I88 engaging a circular track in a sleeve I88 on the shaft 22, to one end of which sleeve the needle stop and start control cams "2,188 are secured. The other end of the sleeve I88 is slotted to receive tongues extending from a collar I82 pinned to the sewing shaft 22 by means of which the cams I82, Illlare caused to rotate-with the shaft while permitting sliding movement thereon.

The movements or the needle and awl starting and stopping control cams occur only when the slot in the timing disk I88 registers with the roll III! on the timing arm of lever I08 and the disk is so. located on the sewing shaft that the cams will be actuated in starting the. machine only at a time just before the awl starting cam III is about to actuate its follower on the control arm 68. At this time, the needle starting cam is approximately 180 away from the roll on the needle control arm 82 so that the awl actuating mocha:- nism will be connected almost immediately after the awl starting cam is actuated. Due to the timed relation between the needle and awl starting cams, the needle will not be connected until the sewing shaft has rotated substantially 180".

Both the needle and awl mechanisms are illustrated in Figs. 84 and in stopped and locked positions at the ends of their strokes most roll H0 is moved through the slot in the disk I88 (Fig. 36) the awl control member disengages the locking arm 88 from the pin and the awl actuating lever 88 is. latched to the lever 88 to connect the awl to its actuating mechanism. The awl then starts its work penetrating stroke. Durneedle actuating mechanism remains disconnected, as illustrated in Fig. 37, until the needle controller memberis shifted to the position of Fig. 31. After the awl has penetrated the work, the needle actuating lever I8 is latched to thedriving lever ll whichby this time is brought into alignment with the needle actuating lever so that upon continued rotation of the sewing shaft, the needle will be set inmotion.

The stopping cycle of the-machine is similar to With the needle and awl driving mechanisms connected to their respective mechanisms, as illustrated in Figs. 23 and 24, the treadle actuated connections are shifted when the slot in the timing disk I88 comes into alignment with the cam roll Ill so that the cam roll passes through the slot and the awl controller member shifts the slotted end of the locking arm 58 into engagement with the pin 88 to disconnect the awl drlvingand actuating levers while the awl bar is in stopping position at the upper end of its stroke, as illustrated in Fig. 25. During this time, the needle actuating mechanism remains connectedyas shown in Fig. The needle actuating mechanism is 180 of rotation in the sewing shaft (see Fig. 31) the'awl actuating lever remaining disconnected disconnected at the. lower end of its'stroke only after substantially pending upon the force applied to the treadle actuated connections; The arrangement is such that sufficient movement'is imparted to the treadle actuated connections to cause the startin came to be shifted into alignment with their cam rolls before the sewing shaft begins to rotate. If the slot in the timing cam is'inproper position, this occurs simultaneously with the downward movement of the treadle rod Ill, but if the timing arm of lever I88 is held from movement by the disk I88Latthis time, the spring ill in the' treadle connections will be compressed until the sewing shaft begins to rotate. The timing arm will then complete its movement, causing the cams to be actuated in the manner stated.

Referring to Fig. 10, the driving clutch is of simple and conveniently accessible construction having a cone-shaped driving member I88 provided with a groove to receive arlrlving belt (not shown). The driving clutch member is rotatably mounted on a bearing I88 supported on the tubular portion of a cylindrical drum I68 slidably mounted in a close fitting circularrecess surrounding .the sewing shaft I8 at one end of the machine frame. To prevent displacement of the driving clutch member I88 along the tubular portion of the drum I88, the driving clutch member has a radial flange extending inwardly towards the tubular portion of the drum and the tubular remote from the work. ,After the timing lever portion has clamped to it outside the flange of the drivingmember a collar I18. The driven,

clutch member comprises a hand wheel I12 keyed to the sewing shaft I8 having an internal conical surface complementing the surface of the driving member I88. To holdthe driving and driven members of the clutclrseparated, the cylindrical drum I88 is urged within the recess of the frame, as illustrated in Fig. 10, by a pairof compression springs I14 coiled around studs I18 passing loosely through openings in the machine frame at the sides of the sewing shaft and having'theirends secured in the drum I88, the springs I'll being compressed between heads on the studs I16 and the machine frame.

To press the driving member I84 against the driven member [12 f the clutch, the shaft II8 has clamped toit a pair of arms III, best shown in Fig. 4, engaging the heads of the studs I18 simultaneously when the treadle rodis depressed, pressing the studs and drum towards the right of Fig. 10 and bringing the friction surfaces of the clutch members together. One advantage of this construction is in the absence of any clutch actu sting connections or clutch supporting bearing external of the machine frame in such a position as to interfere with removal or replacement of the driving belt on the grooved driving clutch member I88. v M

In clutches of machines of a' similar nature heretofore constructed, a clutch actuating lever has been provided withone end disposed close to the exposed end of the sewing shaft or in contact with the outer surface of the driven clutch member-so that in order to remove a driving/belt on and locked at the uppermost end of its stroke, as

indicated in Fig. 30. Thereafter the sewing shaft is free to rotate and-comes to rest as soonas its inertia becomes dissipated.

Rotation of the sewing shaft is controlled by a the driven clutch member, the lever must be disconnected or the ends of the belt separated. With the present construction, removal of the driving belt is'greatly simplified since no obstruction is offered. Furthermore, the drivingclutch member I84 is supported for rotation entirely 'by the sleeve on the cylindrical drum I88, no rotational' force being transmitted, when the machine is stopped, to the sewing shaft I8 which has a separate bearing I15 in the machine frame. Also, oil within thefraine l of the'present machine is into the groove in the presser foot bar.

kept from the clutching surfaces and all of the treadle connections inside the machine frame are protected against injury.

The presser foot 8 is secured to the lower end of a reciprocating presser foot bar I18 slidingly mounted in vertical bearings of the machine frame. The upper end of the bar has coiled about it a presser foot spring I18 compressed between a shoulder on the bar and a threaded bearing sleeve I88 surrounding the presser bar in the machine frame. The presser foot is raised briefly during each sewing cycle to permit the work to be fed, is lowered into work engaging position, and thereafter locked to prevent displacement of the work during the remainder of the sewing cycle by simple and effective mechanism connected with the awl bar 44. Connections are provided also for lifting the presser foot bar to disengage the presser foot from the work at the end of a seam operated from the awl control shaft 62.

The mechanism for actuating the presser foot during sewing comprises a sleeve I82 surrounding an enlarged portion of the presser foot bar I18. The sleeve I82 is slotted at one side to receive a double ended locking wedge I88, the ends of which are disposed in a wedge receiving groove I84 (see' Fig. 6). The locking wedge I86 is fulcrumed for swinging movement on a bolt I88 passing through lugs on the sleeve I 82 so that the ends of the wedge may move alternately The enlarged portion of the presser foot bar on which the sleeve slides, in addition to the groove I 84, has a lengthwise diametrical slot I88 so arranged that when either end of the locking wedge is forced into the groove, the halves of the bar defined by the slot will separate slightly to provide additional clamping and locking action against the inside of the sleeve I82.

To locate the sleeve I82 uniforml dn a position lengthwise of the presser foot bar when the locking wedge I86 releases .the bar, the sleeve is connected to one end of a tension spring I92 stretched between a pin on the sleeve and a pin on the presser foot bar. When the wedge unlocks the bar, the spring I92 draws the sleeve I82 yieldingly downwardly against the outer surface of the eccentric head on a bolt I84 passing loosely through a perforation in the machine frame and having an external check nut I96.

-. under the force of spring I18.

wedge I86. The cam slot.284 is so shaped that when the awl bar 44 is at the highest end of its stroke, the bell crank lever 288 will have actuated the locking wedge and presser foot bar I18 upwardly. As the awl ,barbegins to descend from the position of Fig. 5, the 'roll I98 moves into an active portion of the slot 284, lowering the presser foot bar with the upper end of the wedge still locked in the groove of the presser foot bar until the sleeve I82 engages the eccentric'head on the bolt I84 or the presser foot engages the work, whichever happens first. As soon as the sleeve I82 engages the eccentric head on the bolt I84 or the pressure foot engages the work, movement of the sleeve is arrested and the upper end of the locking wedge is withdrawn from the groove I84 during continued movement of the lever 288. This continued movement of the lever 288 causes the locking wedge to release the presser foot bar and permits the presser foot to engage the work Thereafter, as the bell crank lever 288 completes its motion and until the straight dwell portion of the cam slot 284 is reached, the. locking wedge swings still further in the same direction about the .bolt I88, causing the-lower end of the locking wedge to enter into locking relationship with the presser foot bar. Upward pressure exerted by the work on the presser foot While the lower end of the lockin wedge is within the groove tends to lock the parts with increasing force so long as the bell crank By loosening the check nut I96, the eccentric head of the bolt I94 may be rotated to obtain suitable adjustment, the outer end of the bolt having a screw driver slot. The position of the sleeve is so adjustedthat the mechanism for opcrating the locking wedge will also raise the presser foot a uniform amount (Fig. 5), will lower the presser foot while the upper end "of the locking wedge is pressed into the groove of the presser foot bar, will release the presser foot momentarily as the presser foot reaches th surface of the work so that the presser foot may act yieldingly under the influence of spring I18, and

thereafter the lower end of the wedge will again foot in work engaging position 'lock the presser (Fi 6) v The connections of the presser foot actuating mechanism between the awl bar 44 and the locking wedge I88 include a roll I98 projecting from one side of the awl bar, a bell crank lever 288 fulcrumed on a bolt 282 secured in the frame of the machine and provided with a vertical arm having a cam slot .284 surrounding the roll I88 and a link .288 connecting the other arm of the bell crank lever 288 with an arm on the locking lever 288-remains in position. The locked condition of the pr'esser foot bar is retained by a straight portion of the slot 284 during the remainder of the awl penetrating stroke. During the retracting stroke of the awl, the lower end of the locking wedge is again withdrawn from the groove in the presser foot bar and the presser 'foot raised from engagement with the work after the upper end of the locking wedge is forced within the groove of the bar. This is the condition when the machine is stopped (Fig. 5)

For lifting the presser footbar at the end of a seam beyond the point to which the bar is raised during each sewing cycle to disengage the presser foot from the work,'the forward end of the awl control shaft '82 has an arm 288 forming a toggle with a short link 2I8 connecting a lifting lever 2I2 rotatable on a fixed pivot 2I4. The left end of the lever 2I2 extends beneath a pin 2| 8 on the presser foot bar, which pin also acts as a meansof connection for the presser foot lock actuating spring I92. When the machine is running, the toggle comprisingarm 288 and link 2I8 is broken, as indicated in Fig. 23, the link 2I8 having an elongated slot surrounding a pin 2I8 in one arm of the lever 2I2 to permit movement of the arm 288 after the toggle is broken without affecting the position of lever 2I2.

The awl stop cam 68 is shaped with a changing curvature so that after the cam has been moved along the sewing shaft into alignment with the roll on the awl stop arm 64, the locking lever 58 will disconnect and lock the awl actuating-lever 48 at the upper end of its stroke, the link 2I8 sliding on the pin 2I8 without moving the presser on the stop arm-84, as illustrated in Fig. 28. This dwell portion causes the'control shaft 82 to remain stationary with the awl disconnected at the upper end of its'stroke and the needle connected to its actuating mechanism until the needle has

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