US2354729A - Shoe sewing machine - Google Patents

Description

Aug. l, 1944. F. AsHwoRTH ErAL 2,354,729

` sHoEsEwING MACHINE Filed Feb. 2A, 1942 5 sheetsl-sheet 1 FIL .1

J70 I nuerbons' l, 1944. l AsHwoRTH Erm.'

SHOE SEWING MACHINE 5 Sheets`Sheet 2 WWW MMV. v

Aug.,1,1944. F. A'SHWORTH mL 2,354,729v

SHOE SEWING MACHINE Filed Feb. 2, 1942 5 Sheng-sheet s FLW Aug- 1, 1944- F. AsHwoRTH ET Al. 2,354,729

SHOE SEWING MACHINE Filed Feb. 2, 1942 5 Sheets-Sheet 5 fw L @ai 0 jg Inventors Patented Aug. l, 1944 UNITED STATES PATENT OFFICE SHOE SEWING MACHINE Fred Ashworth, Wenham, and Carl F. Whitaker,

Beverly, Mass., assignors to United Shoe Machinery Corporation, Flemington, N. J'., a corporation of New Jersey Application February 2, 1942, Serial No. 429,206

14 claims. (01.112-61) The present invention relates to improvements in shoe sewing machines and is herein illustrated as embodied in a high speed lockstitch sewing machine of the hooked needle type, Vas disclosed ,in the present inventors U. S. Letters Patent No.

2,271,611 of February 3, 1942., and constructed and arranged to sew the outsole and welted upp'er of a Goodyear welt shoe.

, In the machine of the patent, the work is fed past the stitch forming devices by the operation *of the work support and presser foot, which act to clamp the work and to move with the work the length -of'a stitch. Thereafter, the clamping pressure on the work is relieved and the presser foot and Work support are back fed preparatory to clamping the work at a new location, the distance of a stitch length from the previous one.

-In this machine, as in all outsole shoe stitching machines provided with a clamp feed, difculty has been experienced in securing an accurate and uniform feeding of the work so as to produce a seam having the stitches accurately placed in the work and uniformly spaced. In machines of this type, especially when the machines are operated at high speeds, there is a tendency for the various parts of the presser foot actuating mechanism to vibrate and become more or less displacedas a result of lost motion or lack of rigidity in the connectionsand this tendency becomes more marked as the connections become worn during use. l

One of the most practical and successful presser foot actuating mechanisms which has been used heretofore in this type of machine comprises a single fioating cam actuated lever, which lever .through suitable connections is connected at one vpoint to the cam, at another point to the presser foo-t carrier and at still another point to a locking mechanism, which locking mechanism is actuated during each stitch forming cycle to lock the fulcrum of the floating'lever from movement during the action of the cam on the llever to force the presser foot against the work and to lift the foot from the work, and which is also actuated to release the fulcrum of the floating. lever to permit the lever to be moved about its cam connected endto force the presser foot yield-- ingly against the work. This type of presser foot actuating mechanism has-also been successfully used in outsole stitching machines which are not provided with clamp feeding mechanism in which the work is fed by an awl or needle. In both types of machines, however, this constructioniofpresser foot actuating mechanism has not proved entions have become worn with useor when the machines are operated at high speed. A reason for the failure of these presser Vfoot actuating mechanisms to operate satisfactorily isthat the connections to the single oating lever are of such a nature and are so* arranged-as to cause themotion imparted to certain of the parts to bemultiplied as this motion is imparted to another part and also to cause greater pressures to be exerted upon some of the connections than upon others both while the fulcrum of the floating lever is locked against movement and while it is unlocked. By reason of this inequality in the extent of the motions imparted to the various parts vand in the pressures exerted upon the connections, Vthe vibratoryeffects produced` upon the parts'and connections from any cause are'increased in intensity and as they become excessive, cause the work to be yimproperly clamped in awl andfneedle feed machines and `to be improperly clamped and fed in clamp feed machines.

The particular objects of the present invention are to provide a construction for alligh speed lockstitch outsole shoe sewing machinein whichv accurate and equal feeding movements will be imparted to the work during sewing and in which the di-fliculties referred to will be avoided. In general, the objects are to simplify and .improve the actuating mechanismsof an outsole With these and. other objects in View, afeature of the present invention contemplates the pro- Ivision,-in a high speed outsole shoe stitching machine, of a mechanismfor actuating the work clampingl presser foot having its various parts constructed-and arranged in an improved manner so as to occupy a minimum amount vof space.

in the machine Without interference with4 the desirable location and arrangement of theother stitch formingand workvhan'dling devicesof the machine and also., having its various parts .conf

structedand arranged to distribute thepressures on the various connections 'and pivotal bearings to the best advantage'so as to ylessen wear on the bearings and connections and avoid looseness with consequent vibration in the parts. lThis improved tirely satisfactory, especially after the connecpresser foot actuating mechanism 4isvof that type the presser foot and substantially in the right;` line passing through the work engaging face of' the presser foot and the pivot of the presser,` 2,'

foot lever. By pivotally mounting the presser are connected to the fulcrum supporting lever and thereby the advantages are secured that the presser foot is not lifted by the cam against the tension of the spring during each stitch forming cycle and the connections from the thread measuring mechanism to the presser foot remain at rest until a change occurs in the thickness of the work, thereby eliminating the Wear on these connections when vibrated during each stitch forming cycle, as in prior constructions.

` `In accordance with another feature of the presser foot mechanism hereinafter described, the point of connection of the cam actuated end of the floating lever is arranged to be substantially foot lever midway its length and connecting its rear end to the floating lever inthe manner stated, a simple compact construction is provided, enabling a presser foot spring to be connected to the floating lever between the points of its connection with the actuating cam and-the presser foot, which arrangement does not interfere with the desired location of other parts'of the machine and prevents any excessive pressure from being exertedon the pivotal bearing of the presser foot lever during operation-of the machine. In order'to still further economize in the amount of space occupied by the connections between the cam and the presser foot, the presser foot lever is mounted'in the machine so as to have a substantially horizontal rearward.- ly extending arm and the floating lever which is directly connected by al link to the rear end of the presser foot lever is located above the rearwardly extending arm of the presser foot lever.V In accordance with another feature of the irnproved presser foot .I actuating mechanism, the fulcrum of the lever, instead'of being mounted directly on a' sliding support, as in prior constructions, is fulcrumed intermediateits ends on a supporting lever and the vlocking device for locking the fulcrumfrom movement and for releasing the fulcrurn, is connected to the supporting Ylever at thevopposite side of the fulcrum from the pivot of the lever. By this construction, the pressure on the-locking devices'is reduced, and by properly proportioning the arms of the floating and fulcrum supporting levers, the pressures at the ends of the floating lever and on the locking devices can be equalized. In the embodiment of the invention hereinafter specicallydei scribed, the floating lever andthe fulcrum supporting lever are of the same length, 'and the floating lever 'is fulcrumed-midwayvbetween the pivot of the supporting lever and its-point of connection to the locking devicesl The movements of both ends of ,the floating lever, While the fulcrum is locked against movement, are thus equal and any movement of the fulcrum support While unlocked imparts equal movementsto the end of the floating lever connected to the presser foot lever and to the end of the fulcrum support connected to the locking devices. The position of the fulcrurn of the floating lever is shifted, as in prior constructions, upon a change in the thickness of the work, and by reason of the construction above described, sufficient movement is im'- rparted to the fulcrum support to permit the spring which forces the presser foot against the work While the fulcrum support is unlocked to act advantageously when connectedto the fulcrumsupport. Bythis constructionalso, sufficient movement is imparted to the fulcrumsupport so that it can be advantageously connected to the thread measuring or pull-off. mechanism., In the construction hereinafter described, both the actuating spring and the thread measuring mechanism concentric with the fixed pivot of the fulcrum vsupporting lever while the presser foot is in a position of nearest possible approach to the work support, a stop being provided to limit the approach of the presser foot in this direction. In connection with this construction, means are provided for an adjustment of the fulcrurn of the oating lever with relation to the supporting lever and thereby an adjustment of the position of nearest possible approach to the work support of the presser foot may be made without modifying the operation of the cam and of the spring when actuating the presser foot.

Other features of the invention consist in novel and improved devices, combinations and arrangements of parts Vhereinafter described and claimed, the advantages of which will be readily understood by one skilled in the art from the following description taken in connection-'with the accompanying drawings illustrating one embodiment of the invention.

In the drawings, Fig. 1 is a view in front elevation of a part of an outsole shoe sewing machine embodying the features of the present invention; Fig. 2 is a detail side view, partly in secition, of the presser foot actuating mechanism and a portion of the Work support with no work in the machine; Fig. 3 is a sectional plan View taken along the line 3 3 of Fig. 2; Fig. 4 is a sectional plan as viewed along the line 4-4 of Fig. 2; Fig. 5 is a sectional detail view of the presser foot lock device in front elevation; Fig. 6 is adetail View in front elevation of a portion of the presser foot actuating mechanism; Fig. 'l is a detail view, partly in section, of the work support carrier, its mounting shaft and feed actuating mechanism; Fig. 8 is a diagrammatic plan view on an enlarged scale illustrating the manner of obtaining the rearward pull on the work during work feed; Fig. 9 is a view in detail elevation, partly in section, of the work support and carrier; Fig. 10 is a side view on an enlarged scale of the upper part of the work support and a shoe guided thereby, shown in section; Fig. 11 is a View in side elevation of a portion of the Work support and presserfoot together with a novel form of back gage; Fig. 12 is a plan view of the work support and back gage; Fig. 13 is a perspective view of the sewing thread lock and pull-off actuating members; Fig. 14 is a sectional view of the` same parts, taken along the line I4-I4 of Fig. 1, together with the thread locks illustrating the manner of operation; Fig. 15 is a plan view of the looper actuating mechanism; Fig. 16 is a. side View, partly broken away and in section, of the same parts; and Fig. 17 is a front view, ypartly broken away and in section, of the looper actuating mechanism.

The machine illustrated in the drawings is of the type disclosed in prior U. S. Letters Patent O f Ashworth No. 1,169,909 of February 1, 1916,

No. 1,824,063 of September 22, 1931, and No. '2,015,654 of October l, 1935, as well as in the Patent No. 2,271,611, above referred to. The machine is equipped with a curved hook needle 2,

'a needle guide 4 (see Fig. 11), a curved awl 6, la thread case 8 mounted within a shuttle or loop taker, needle threading mechanism including a looper I and a thread finger I2, a work support I4, a presser foot I6, back gage I8 and other stitch forming devices similar to those of the above patents, except as hereinafter pointed out. A driving and stopping mechanism also is provided for bringing the sewing shaft of the machine, indicated at I9, to rest with the work free to be removed. The general arrangement of the machine is as usual, with the sewing shaft located behind and above the point of operation of the stitch forming devices and substantially parallel to the line of the seam formed thereby.

The work is fedl in the illustrated machine, as in the machine of Patents Nos. 1,824,063 and 2,271,611, by the movement of the work support and presser foot while clamping the work. During clamping engagement of the presser foot with the work, a measured amount of needle thread correspondingto the position of the presser foot is pulled off from the supply, the thread after measurement being lockedy against further movement towards or away from the supply until each stitch is set in the work.

As has been'stated, the illustrated machine is provided with an improved presser foot actuating mechanism of the type comprising a floating lever 'in the connections between the presser foot and its actuating cam. As best'shown in Fig. 2, the

presser foot I is secured to the forward end of a substantially horizontal presser foot "lever 24 pivotally mounted at 26 on the feed carriage to which is also secured the cooperating work support,` as hereinafter described. The floating lever is'indicated at 22, and in order to leave the space beneath the horizontally extending rear arm'of the presser foot lever free to be occupied by other parts of the operating mechanism of the machine, is located above the presser foot lever; The lfnl.- crum of the floating leveris located intermediate the ends of the lever and vone end of the floating lever is connected directly to the rear end ofthe presser foot lever by a link 28 while the other end of the floating lever is connectedfto a cam actuated lever by an offset fork-ended link 52. The presser foot lever 24 is pivotally mounted midway its ends, and the point of connection between the rear end of the lever and the link 28 is such that the lever 24 is the equivalentof a straight lever with equal arms. Moreover, said point of connection is sufficiently" close to the right line 'passing through the work-engaging face of the presser foot and the pivot 26 that the lever can be actuated to clamp the work firmly without subjecting the pivot bearing to excessive pressure.

Ther supportingV4 lever for the fulcrum ofthe floating lever is indicated at 2t. This support, in the illustrated machine, isa frame resembling somewhat the letter H, -and is pivotally mounted AuponA a pair of fixed pins `32 extending towards each other through bosses 'in 'angular bracket arms one of which is attached tota cover plate 34 for a box 36 ,of thelocking mechanism hereinafter described, and the: other 4of which is connected to the machine frame. The lever 20 is arranged horizontally, and the pivot pins'32 engage the ends of the arms which extend forwardly from the cross bar of the H and which are separated sufficiently to permit the passage between them of one end of the floating lever 22. The `floating lever 22 is also arranged in a substantially horizontal position and is pivotally mounted between the arms of the lever 20 which extend rearwardly from the cross bar of the H, the fulcrum of the 'lever 22 .consisting of a pin 3U, the ends of which are supported by thearms ofthe lever 20.

The locking devices for locking the fulcrum of the floating lever from movement during each stitch forming cycle and for releasing the fulcrum are connected to the fulcrum supporting lever 20 at the opposite side of the fulcrum' of the floating lever from the fixed pivot pins. 32, upon which the supporting lever is mounted.v As best shown in Figs. 2 and 3, one of the arms of the lever 2t, extending rearwardly from the cross bar of the H, is of such length that a connection from the locking devices to the arm can be made at a point which is thek same distance from the fulcrum of the oating lever as are the pivot pins 32. The link which connects the locking 'devices to thefulcrum supporting lever -20 is indicated at 56 and it will be noted, as clearly shown in Fig. 3, that this link is located at one side, inthe direcL tion of the seam line,` of the link 28 connecting` the floating lever 22 with the presser foot lever and that the arms of the levers 20 and 22 are also located side by side in the direction ofthe seam line. This arrangement of levers and conn.ec'. tions provides a compact construction which leaves the space directly 'to the rear of the sewing point available for other operating connectionsin the machine and which, on account of the short length of each lever arm, has substantial rigidity.

The manner in which theillustrated construction acts to distribute the pressures on the various connections and' pivot bearings willbe apparent from an inspection of lFig. Movement-simparted vto the floating lever` about its'fulcrum while the fulcrum is stationary move the ends of the lever equal distances andconsequently the pressures on the connections at each end of the .lever are the same. Also, the pressure'onthe fulcrum of the lever is twice the pressure at the ends of the lever. Due to the fact that the fulcrum of the iloating lever 22 is midway the length of the supporting lever 2D, the pressure on the locking devices connected to the rear end of the lever is one-half that on the fulcrum of the oat; ing lever or the Ysame as the pressure at each end of the floating lever. Also, any `movement of the fulcrum of the floating lever,'while.the fulcrum supporting leveris unlocked, results in a movement of the connection to the locking devices twice that of the fulcrum. i

In the illustrated construction, the spring which forces the presser foot against the-'work while the fulcrum supporting lever 20 is unlocked?, is connected to act on the supportingle'ver between the points of a camand presser foot conY nection at the same point as the locking devices. as hereinafter described, so that the presser foot is not lifted against the force of the spring. In forcing the presser foot towards the work support, the spring swings -the fulcrum supporting lever 20 about its xed pins 32 and during this movement the fulcrum, acting on the' middle point of the iioating lever 22; swings thisflever aboutitspivotal connection with the link 52. As the lever 22 is thus swung, its rear end,'which is connected by the link 28 to the presser footv lever,

travels twice the distancer of the fulcrum, or a'dis-l tance equal to that. traveled by the lockconnected end of4 thefulcrum supporting lever 20.

The extent of movement and leverage provided by these connections results in an efficient and reliableadjustment of the presser foot to the thickness of the'work in the machine.

In presser foot mechanisms of the type comprising a floating lever in thev connections between the actuating cam and the presser foot. the fulcrum remains stationary during the cam actuated movements ofthe presser foot and changes its position only upon an increase or decrease in the thickness of the work. In the illustrated construction, this change in the position of the fulcrum of the floating lever is utilized to 'control the action ofthe thread measuring mechanism by which thread is pulled from the supply for each stitch, and to this end a connection hereinafter described is made from the thread measuring mechanism to the lock connecting end of theI fulcrum supporting lever 26. As has been explained, this end of the leverv 29 remains stationary except `as a change occurs in the thickness of the work but has a range of movement twice thatf of the fulcrum whenever the fulcrum is moved. Accurate and reliable control'of the thread vmeasuring is secured by this construction and arrangement, and constant vibration of the 'controlling connections during sewing is avoided.

The cam lever for actuating the presser foot is similar to that of the 'machine in Patent No, 2,271,611 above identified and-comprises a part 38 having a cam roll 40 and a part 42 having an arcuate slot44. `The two parts of the cam lever are fulcrumed loosely on a shaft 46 and joined together through a one-way yielding connection including an adjustable spring-pressed set screw V48 in the'part 42. Adjustably clamped within the slot 44 on the lever part 42 is a releasable stud 50 forming a pivot for the upper end of the offset fork-'ended link 52', bestshown in Fig. 6, embracing the slotted portion of the cam lever at Vits upper end and surrounding an arm of the floating lever 22 at its'lower end. The lower end of the link 52 is pivotally connected to the floating lever 22 by a pin 54 secured within the lever f 22. Adjustment of the stud 50 along the slot 44 changes the work clampingand releasing action of the presser foot. '4 y v The 'presser foot lock of the present machine is similar to that disclosed in Patent No'. 2,271,511

but is mounted with its lengthwise dimension vin a substantially vertical position, as compared with an approximately horizontal position of the lock of said patent and with an angular position of the lock in thev patent to Gouldbournet al. No.

2,054,078 of September 1936." The movable members of the lock are connected through a pair of parallel links 56 to the rearward arnrof'lever which has the fixed fulcrum pivot. The upper ends of linksvv 56 are disposed at the sides of lever 2U, the point ofv pivotal connection beingV defined by the' pin 58 kand the lower ends of the links 56 carry a'pin 6|) passing through central and outer wedge members 62, the central one vof which is disposed between the links 56 and the cuter ones of which are located outside the links. The wedge members 62 are slidingly mounted within the lock box 36 and are retained therein Vby the cover plate 34.-V Between the wedge members within the lock box are aspacing piece 64' and a series of steel lockingrolls 66 at opposite sides of the central wedgev member. The Alower "end of the series of rolls Vrests against a relatively fixed bar l68 in the lock box and the upper'end is acted upon by a locking finger 'l0 secured toashafti2hav- `enable the lock to respond more quickly and positively when actuated.

y"Ifo actuate the lock actuating link 16 rearwardly, the rearward reduced end is surrounded withl a relatively heavy spring 78 compressed between -a kcheck nut vthreaded on the reduced end of 4 the link and a perforated bracket 82 through the perforation of which the link passes. ,The bracket 82, being secured to the-frame of the machine, causes the link 76 to be drawn rearwardly until the locking finger engages the uppermost locking roll 66. To release the lock, the link 76 is moved forwardly against the force of the spring 18 and the locking rolls 65 are relieved of pressure by a cam actuated lever 84 fulcrumed on a cross shaft 86 secured to the frame of the machine. The upper arm of the cam lever has a roll engaging a cam on the sewing shaft I9 and on its lower arm is a forked portion cooperating with a at surface 89 formed by a shoulder on the link 16.

The presser foot spring of the present machine is not connected directly to the floating lever 22, as in Patent No. 2,271,611, but acts on the floating lever through the links 56 connecting the equalizing lever 20 with the wedge members of the lock. To connect the spring to the links 56, the upper end of a C-shaped link 88 is pivotally connected between the links 56 by a bolt 90 and the lower forked end of the C-shaped link is perforated to receive a pin 92. The pin 92 also passes through the upper end of an H- shaped link 94 carrying a clamp bolt 96 at its lower end; The clamp bolt 96 is adjustably secured Within an arcuate slot of a lever 98 fulcrumed on a shaft |00 and connected to the presser foot spring, indicated at |92, by a link |04 and a lever |06 mounted on a xed stud |08. The presser foot spring |02 is connected at its rearward end to the lever |66 and extends forwardly towards the front of the machine frame where it is held under tension by means described in Patent No. 2,271,611.

'I'he C-shaped link 88 and the H-shaped link 94 being under compression, are held in alignment by the action of the connecting pin 92 slidably arranged within a slot ||0 (Fig. 2) in a portion of said outer wedge member 62 carries a headed pin I2 which is received within a diametrical passage in the pin 92. The upper headed end of the pin ll2'serves as a backing plate fora spring-pressed plunger H4 acting betweenfthe outer and rcentral wedge members to takek up lost motion between the wedge members and render the lock self-energizing, as indicated more fully in the patent to Gouldbourn et al.

The recesses in the lock box 36 are so formed 'for the presserfoot lever 24. construction of the present feed carriage differs that when the pin 92 is in its highest position, that is, when the Ipresser foot is in its position of nearest possible approach to the work, the pivot pins 32 and 54 are brought accurately into alignment. To overcome slight manufacturing irregularities, the floating pin 30 is provided with enlarged and reduced eccentric portions at its ends and the fulcrum supporting link 20 has mounted in it a clamp bolt ||6 for securing the pin 30 against rotation in suitably adjusted .posit-ion. When rotated manually in the link 20, the eccentric floating pin 30 will cause the presser foot to change its position of nearest approach to the presser foot without requiring change in the positions of the cam lever or lock. For changing the amount of clamping force applied by the actuating cam lever 38, 42 to the presser foot, the clamp stud 50 is shifted along the slot 44 and to avoid the necessity of changing the adjustment of'the eccentric pin 30 for each change in the position of the clamp stud in the slot 44, the slot 44 is made of arcuate shape concentric with the center of the pivot pin 54 when the presser foot is in its position of nearest possible approach to the work support, which position is determined by the engagement of the pin 92 against the upper end of the recesses in the lock box 36.

The shaft not only forms a fulcrum for the lever 98, but also carries a thread measuring arm i9 similar to that of the machine disclosed in Patent No. 2,271,611 referred to, in accordance with the thickness of the work engaged by the presserl foot. The thread measuring mechanism is thus controlled through connections to the rear endA of the fulcrum supporting lever 20.

lTo change the ratio by which the amount 'of thread measured varies with respect to the thickness Vof the work operated upon so that thread may be measured in an amount varying directly with the thickness of the work or varying at a lesser rate, as explained more fully in Patent No. 2,271,611, the slot which receives the clamp bolt 36 in the lever 98 is made eccentric to the pin 92 with the presser foot stopped by the pin 92 in its position of nearest approach to the work support, in which position .the pivot pins 32v and 54 are in alignment. If the position of the clamp bolt 9S is changed while the parts are so located,

no change in position of the spring or of the i presser foot occurs so lthat the interengaging 'portions of thread in the stitches will always be set in the work' in the same relation to the outer surfaces of the work V,while sewing the thinnest grades of work, the presser foot being at, or apeproximately in its position of nearest approach to the work support under these circumstances.

yThe mechanism for imparting a feeding movement to the work support and ,presser foot while clamping. the work is best shown in Figs. 7 to 10| inclusive. The general arrangement'of this mechanism is the same' as in the machine of Patent No. 2,271,611 and includes a cam on the'main sewing shaft, a cam lever '|-|8, a' link connecting the cam lever. with :the central joint vof a pair of toggle links |22 and |24. The toggle link |22 is pivotally mounted on a yoke |26 andthe other link |24 is connected to a rearj wardly extending arm on a feed carriage, |28 of a shape having a lug for the pivotal mounting 26 The particular slightly from that of Patent No. 2,271,611 in that '.the present carriage is formed as a single integral "piece whereas the carriage cf the saidk patent vis ward pull at right angles to the'line of feed on the outsole of a shoe adjacent Vthe point of sewing operations. In the embodiment of this feature, the work support |4 which is of U shape, is clamped to parallel portions of the feed carriage |28 and is formed along its Work engaging surface with a raised portion |32 for causing the pressure exerted on the work to be centralized at a mid-point such as |34 on the portion |32 as the work is clamped by the presser foot. During feeding movements of the work support, the movements imparted to the work, unless otherwise prevented, are the same as the movements of the mid-point |34.

i Referring to Fig. 8, the pressure centralizing portion |32 is indicated by avsomewhat D- shaped outline and is locatedon the work support at the seam side of the needle and awl 'paths so that in feeding the work, it moves from the full-line position to the dot-dash line position further away from a point of intersection |35 between a line |36 passing through the center of the pivotal mounting shaft |30 at right angles to the line of feed indicated at |38, the Yline of feed passing through the needle and awl path. T he needle and awl paths are coincident in the -illustrated machine at vthe location of the awl 6. The awl Bis located at the trailing point of the intersection |35, the pressure centralizing point |34 on the work support being located still further to the left away from the intersection. As a result of the swinging movement of .the work support about the lshaft |30, the pressure centralizing point |34 moves appreciably `out of the line of feed along an arcuate path |40 and rearwardly by a distance |42 in feeding the work. Since the work is clamped by the work support4 and presser foot during feeding movement, a rearward pull isV exerted on the work itself. Back feeding movement of the worksupport and presser foot occurs when the clamping pressure of the foot is released from the Work so that `during .back feeding move- `ment, the pressure centralizing ,portionA |32 of the work ,support moves .from thehot-dash position to the full line position and forwardly by the distance |42.y In vthe full line position of the pressure centralizing portion |32, the work is again ,clamped soY that the rearward pull which is directed at right .angles to the line vof feed is continued from onesewing cycle to another, the awl being projected into and holding the work during yeach back feeding movement. f l.

'Ihe rearward pull ofrthework supportk and ypresser foot on the work has further desirable Yresults due to the inclination pof the pivotal mounting shaft |30 for the feed carriage, as indicated in Fig. 9. In Sewingabout the `shank Aof a `Goodyear welt shoe |43, shown in Fig. 10, `andabout the entire marginal portion of other types of shoes, a front face |44 of the Work sup- U,port disposed vat an angle to the work Asuplzrorting and pressure centralizing surfaces serves asa gagehagainst the outer last supported surface of vthe shoe upper indicated at |46. In a 6 Goodyear welt shoe, the shoe is presented by the operator in the' position shown with the upper against'.the gag'ing surface |44 and with the projecting margin ofv welt |48 on the work supporting surface. The angle of the .l pivotal mounting shaft` is such that theforward movement of the work support during backfeed of 'thejwork support causes the gaging surface .|44and the work supporting surface of the work 'supportto be thrust with e'qual pressures against both the upper and welt. The inclination of the shaft |30 for this purpose is selected at an anglewhich Will cause a line |50 bisecting the angle between the work gaging and supporting surfaces on the work support to intersect the vaxis of the shaft |30 at right anglesgthe forward thrust of the work support when so arranged being exerted along this line.

In order to enable the operator to hold the work against the back gage with little or no muscular effort, according to present day practices, a shoe is presented to the machine with the edges of the welt and outsole substantially out of parallel with the line of feed |38. During feeding movements of a shoe so presented to the present machine, there is a tendency lto choke or retard the feeding movement of the shoe whenever a back gage for guiding the rearward edges of the work is employed. With the present construction and mode of operation, the rearward pull exerted by the work support and presser foot'on the work enables the operator to present the work with the edge more nearly parallel to the line of feed than possible heretofore and at the same time, to hold the work against the back gage without substantial muscular effort.

As a means for accentuating the effects of rearward pull on the work, the feeding and back feeding movements are so proportioned that the time of feed is relatively long, as compared with 4the time of back feed. When ythe machine is operating at high speeds, the inertia of a shoe is easily overcome `during Vthe relatively long feeding movement and after the clamping pressure on the work is released, the relatively short back feeding movement enables a new clamping grip to be obtained on the work before any substantial forward movement of the work is possible. 1

Any link mechanism is subject to wear and looseness vin its pivotal rconnections after long continued use and to offset the effects of Wear in the work feeding mechanism of the present machine, lthe rearwardly extending arm of the feed carriage |28 is acted upon by a plunger |52 slidable in a'passage 'in the machine frame and backed by a compression spring |54. The spring |54 is retained in' the passage of the frame by a 'cap screw |56. VBy reason of the rel- -atively long feeding movement imparted'to'the feed carriage by the feeding mechanism, it is 'possible for a lightis'pri'ng acting on the plunger |52 to take up all'of the back lash in the feed'- ing mechanisms even when the machine is operating at high speeds.'

The back gage is similar to that of the machine disclosed in Patent No. 2,271,611 yand is located with' the end of its trailing work engaging edgein close proximity to the portion |32 of the work support which acts to concentrate the pres:- sure on the work, as indicated in Fig. 12.`A With the end of the back gage so located, theoperator fis-enabled to guide the *work moreeffectively and .ber for the pull-off actuating arm |88 extending astuce to change its position easily while presenting the work to the machine. 1

Torprevent the outer lower corner of the welt fromA becoming wedged or cut between the work support and the back gage as the work isv cornpressed by the presser foot, the present back gage is provided with a lip |58 having a horizontal work engaging surfacev in front of the vertical work engaging portion of thevback gage, as shown in Figs'll and 12.v The angularly disposed surfaces formed by the lip |58 and the vertical edge engaging surface of the back gage provide a trough which the outer lower corner of the welt travels To enable the lip to approach as close as possible to the work engaging surface of the work support, the work support is cut away at |60 to form a shoulder |62. During back feed movement of the work support, the shoulder |62 moves towards the lip on the back gage and raises the edge of the welt onto `the surface of the work support.

Like the machine of PatentNo. 2,271,611 the illustrated machine has a pull-off actuating mechanism including a curved slotted arm |64 (see Figs, 13 and 14) rotatably mounted on a shaft |66 in alignment with the thread measuring shaftV |00 and acting between a pair of guides on the measuring arm 9 to draw off a supply of needle thread sufficient for each stitch. Also mounted on the shaft |66 are a pair of thread lock actuating arms |68y and |10. These arms are formed with cam surfaces at their extremities which cooperate with shoes |12 and |14 for clamping the thread at either side of the pulloff against thread guide rolls |16 and |18. The pull-off and thread lock arms of the machine in the patent last referred to are secured to the shaft and to concentric sleeves, one inside the other on the shaft |66. During rotation of the shaft to actuate the pull-off arm corresponding to the arm |64, there is a tendency for the shaft to impart movements to the cam arm supporting sleeves so as to interfere with proper operation of the thread locks or to open one of the locks temporarily when it should be closed.

In order to prevent interference between the pull-off arm and insure proper operation of the locks in the illustrated machine, the pull-off arm |64 and lock actuating arms |68 and |10 are constructed and arranged to oscillate on the cross shaft |66 in such a way that no pressure radially of the shaft will be transferred from one to another.V VInstead of mounting the pull-,off arm directly onV the shaft |66 and the lock actuating arms onv sleeves supported one inside of the other, all of ,the arms are rotatable directly on the shaft |66and are connected with their actuating mechanisms by means of struts |80, |82 and |84. The strut |60 connects the pull-olf arm with an integrally formed yoke |86 'acting as a bearing memfrorn the yoke. Between the bearing Vportions of the yoke is va second bearing member'lS having an arm |92 for operating the lockactuating arm |68.' The strut |84 connects thelockiactuating arm |10 with a bearing member |84 havingY an operatingarm |96.v The lock actuating .arm |68 thus has triplicate bearings' directly on the 'shaft |66 and the pull-off and other lock'jactuating Aarms |10 and |64 have double'vbearings spaced along the shaft so that actuationl of'anyof the arms'will not affect anyv of theothersd' .,Ifhecros's shaft |66 itself is fixed inja bracketjill secured tothe frame of the machine 'and' having twoshaft supporting bosses,A one at the right end of the shaftv |66 and one at an intermediate position be# tween the bearing members connected by the struts.

The mechanism for actuating the looper I0 of the present invention is constructed to move in a curving path generally in the line of feed, as in the machine of the Patent No. 2,271,611 and to avoid application of excessively heavy forces in any of its individual parts, ample bearing'su'rfaces being provided for extreme durability'in use. The looper proper is in the usual Vform with an upstanding perforated thread receiving stem and in its present form is clamped to a two-part carrier 200 slidable lengthwise along an arrni202 provided with rectangular guiding surfaces inside the carrier, the lower edges of the carrier having anges engaging grooves in the arm. The parts of the carrier are secured together at the forward end by a bolt 204 which secures the stem of the looper to the carrier andat its rearward end by-a threaded stud and nuts 206 passing through the carrier parts and a block 208 of a shape corresponding to that of the arm 202, The arm 202 swings on a pivot pin 210 having a conical wear compensating portion fitting a corresponding opening in the carrier and clamped within a supporting bracket 2I2 secured to the machine frame. A Swinging of the arm on its pivot pin causes the perforatedvend of the'- looper to move to the right and left of the needle.

To impart a forward and rearward component of movement to the looper during the swinging movement of the arm 202, block 208 has clamped therein a headed pin2i4 on which is rotatable a conical roll 2I6 engaging an S-shaped cam slot 21T formed in the bracket 2|2. The central portion of the bracket is recessed at 2l'8 to provide space for a pin 220 having a conical wear vcompensating head fitting a correspondingly shaped opening in the arm 202. The pin 220 is secured within one end of an actuating link-222 pivotally connected to a -cam lever 224 fulcrumed at 226 on a fixed vertical shaft. The cam lever 224 is provided with a roll 228 engaging a cam 23B] on the sewing shaft I 9.'

Certain of the mechanisms which have been illustrated and describedare not claimed herein but formv the subject-matter of divisional applications, the looper actuating mechanism being claimed in application Serial No. 488,966, led Mayv 29, 1943, the pull-olf and thread lock actuv` ating mechanism being 'claimed in application serial No.' 496,464, med Juiy 28, i943, andthe work feeding and edge gage mechanism being claimed in application Serial No.7`498,484, filed s.

August 13,1943. l v, N I The nature and scopeof 'the invention having been indicated and a particular-embodiment of the invention having been described, what is claimed is:

l. An outsole shoe lstitching machne'having,

in combination, stitch forming devices,'a workv support, a presser foot, mechanism for actuating the presser foot comprisinga presser foot lever pivotally mounted midway its length at one end of which lever the presser foot s mounted, an actuating cam, a iioating lever, a connectionfrom the cam to a point on the floating lever, a link directly connecting another point on the oating lever to the end oi the presser foot lever remote from the presser footV ata point to 'form equal arms on the presserfoot lever, locking devices for locking the fulcrum of the floating `lever from movement, means for actuating the'locking devices to lock and release the fulcrurnduring each i support while the fing leverlfrom movement; means Vfor A' the locking Adevices-tolock-and* rele'as Y 'crum supporting' leverfduring eachs'ti'tch-fferming cycle, and avlspring'` acti'ng'on the floating :lever between `the pointsof cam and e v fin combination, stitch formingV er font 1lever comprising a floating leven* stitch forming cycle, andk a spring acting on the floating lever between the points of connection with the cam and the presser foot to press the foot towards the work support while the iulcrum` of the floating lever is released.

2. An outsole shoe stitching machine having, in combination, stitch forming devices, a yWork support, a lpresser' foot, mechanism for actuating the presser foot comprising a presser foot lever pivotally mounted midway its yends and having a substantially horizontal rearwardly extending arm on the forward end of which leve'r the'presser foot is mounted, an actuating cam, a floating lever located above the rearwardly extending arm of the presser foot lever, a' connection from the cam to a point'on the floating lever, a link directly connecting therea'r end of the presser foot lever to another' point on the floating lever, locking devices for locking the fulcrum of the oating lever` from movement, means for actuating the locking devices to lock and release the fulcrum during each stitch forming cycle',y and a-spring actingvon the connectionsfbetween-th'e cam` and the presser footfto press the foot towards the work support'whi'le the fulcrum is released.

v3. An outsole shoe stitching machine having; incombination, stitch vforming devicesy'a worlk support', a presser foot, presser footy actuating `mei'zha'nism comprising a presser foot`leverA on which then presser foot is mounted, an actuating cam, connections between'the cam and the presser foot lever comprising a floating-lever, a' supportinglever on 'which the `iloating lever is fulcrumed, lali-'connection from the cam to a'point on the fio-ating lever, a connection :from the presser foot lever to another point on theiioatinglever', locking devices for locking the fulcrumsupporting`VVV lever from movement, means for actuating Athe loc-king devicesto lock andrele'ase the fu-lcrum supporting lever during each stitch forming cycle, and a spring'acting on the oating lever between the points of cam and presser foot connection to press the foot towards 'the work fulcrum of the ioating lever is released. 7 1 4. An outsole shoe stitching machineV having, in` combination, stitch forming devices; a`V Work supporna presser foot, presser footactuating mechanism comprising a presser foot levervon which the presser foot ismounte'd, an actuating cam, connections between the c'am'and the presser feat lever comprising a floatingflever, a fulcru'm :supporting lever en whichl the floating lever 'isffulcrurne'dfintermediate its ends, aVc'clruiecL tion'frornftlie cam to a point on the floating vlever at one'side'of 'its fulcrumay 'connection from the presser foot lever -to yapoint vvon rthe floating leverV atth'e opposite side offitsy "fulcrum,

locking"` devices forV locking the fulcriim support- ,page e thev full presser foot'connection to press the foot towardsthe work sup?- port while the fulcrum of the noatinglever Ais jreleas'ed.'

jAnfo'utsolc shoe stitching machine ng, devices,v 'a werk "snpport, avpre'ssercfoot, "presser foot actumechanism comprising 'a l `presser foot lever io whiclilthe presser foot is Vmountedy "an actuating 'fcamj connections between the cam and ithepres's;

crum supporting lever pivoted at one end of the same length as the floating lever, at the central point of which the floating lever is fulcrurned midway its length, a connection from the cam to one end of the floating lever, a connection from the presser foot lever to the other end of the floating lever, locking devices for locking the fulcrum supporting lever from movement, a connection from the locking devices to the end of the fulcrum supporting leverremote from its pivot, means for actuating the locking devices to lock and release the fulcrum during each stitch forming cycle, and a spring acting on the connections between the cam and the presser foot to press the foot towards the work support while the fulcrum is released.

i 6. An Youtsole shoe stitching machine having, in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism comprising a presser foot lever on which the presser foot is mounted, an actuating cam, connections between the cam and the presser foot lever comprising a floating lever, a fulcrum support on which the floating lever is fulcrumed intermediate its ends a connnection from the cam to a point on the floating lever at one side of its fulcrum, a connection from the presser footlever to a point on the floating lever at the opposite side of its fulcrum, locking devices for locking the fulcrum support from movement, means for actuating the locking devices to lock and release the fulcrum support during each stitch forming cycle, a spring acting on the connections between the cam and the presser foot to press the foot towards the work support while the fulcrum support is released, and thread measuring mechanism comprising a thread measuring arm and a connection from the thread measuring arm to the fulcrum support for moving the thread measuring arm upon movement of the fulcrum support while released.

7. An outsole shoe stitching machine having, in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism comprising a presser foot lever on which the presser foot is mounted, an actuating cam, connections between the cam andthe presser foot lever comprising a floating lever, a fulcrum support on which the floating lever is fulcrumed intermediate its ends, a connection from the cam toa point on the floating lever at one side of its fulcrum, av connection from the presser foot lever to a point on the floating lever at the opposite side of itsV fulcrum, locking devices for locking the fulcrum support from movement, means for actuating the locking devices to lock and release the fulcrum support during each stitch forming cycle, a spring acting on the connections between the cam and the presser foot to press the foot towards the work support while the fulcrum support is released, a thread pull-oi mechanism, and aconnV fulcrum support acting to Vary lthe amount of thread pulled from the supply with variations in the position of the fulcrum support of the floatinglever.

8. An outsole shoe stitching machine having, in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism-comprisingv a presser footl lever on rwhich the presser foot is mounted, an actuating cam, connections between thecam and the presser foot lever comprising a floating lever, a fulcrum supporting lever on which the floating lever'V nasa] fulcrum, locking devices for locking ction from the pull-oir mechanism tothethefulcrum 'supporting lever from movement, means for actuating the locking devices to lock and release the fulcrum supporting lever during each stitch forming cycle, a spring acting on the connections between the cam and the presser foot to press the foot towards the work support while the fulcrum supporting lever is released, a thread pull-oil mechanism, and a connection from the pull-oir mechanism to a point on the fulcrum supporting lever on the opposite side of its fulcrum from the pivot of the fulcrum supporting lever to vary the, amount of thread pulled from the supply with variations in the position of the fulcrum of the iloating lever.

9. An outsole shoe stitching machine having, in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism comprising a presser foot lever on which the presser foot is mounted, an actuating cam, connections between the cam and the presser foot lever comprising a floating lever, a fulcrum supporting lever mounted on a xed pivot, on which lever the floating lever is fulcrumed, locking devices for locking the fulcrum supporting lever from movement, means for actuating the locking devices-to lock and release the fulcrum supporting lever during each stitch forming cycle, a spring acting on the connections between the cam and they presser foot to press the foot towards the work support while the fulcrum supportV is released, a connection from the presser foot lever to a point on the floating lever, and a connection from the cam to another pivot point on the floatinglever, which point is substantially concentric with the fixed pivot of the fulcrum supporting lever while the presser foot is in a position of nearest possible approach to the Work support. Y

10. An outsole shoe stitching machine having, in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism comprising a presser foot lever on which the `presser foot is mounted, an actuating cam, connections between the cam and the presser foot lever comprising a floating lever, a fulcrum supporting lever mounted on a xed pivot on which lever the floating lever is fulcrumed, locking devices for locking the fulcrum supporting lever from movement, a connection from the locking devices to the end of the fulcrum supporting lever remote from its pivot, means for actuating the locking devices toV lock and release the fulcrum during each stitch forming cycle, a spring acting on the connections between the cam and the presser foot to press the foot toward the work support while the fulcrum is released, and means for adjusting the fulcrum of the floating lever on the fulcrum supporting lever.

l1. An outsole shoe stitching machine having, in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism comprising a presser foot lever on which the presser foot is mounted, an actuating cam, connections between the cam and the presser'foot lever comprising a floating lever, a fulcrum supporting lever mounted on a fixed pivot, on which lever the floating lever is fulcrurned` locking devicesv for locking the fulcrum supporting lever from movement, means for actuating theY locking devices to lock and release the fulcrum supporting lever during .each stitch forming cycle, a spring acting on the connections between the cam and the presser fcot to press the foot towards the work support while the fulcrum supporting lever is released, a connection from the presser foot lever to a point on the floating lever, a connection from the cam to another point on the iioating lever, which pivot point is substantially concentric with the fixed pivot of the fulcrum supporting lever While the presser foot is in a position of nearest possible approach to the work support, connections from the locking devices to the end of the fulcrum supporting lever remote from its pivot, and means for limiting the movement of said locking connections in a direction to prevent movement of the presser foot towards the work support beyond the position where the connecting point of the floating lever to the cam is concentric with the fixed pivot of the fulcrum supporting lever.

12. An outsole shoe stitching machine having, in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism comprising a presser foot lever on which the presser foot is mounted, an actuating cam, connections between the cam and the presser foot lever comprising a floating lever, a fulcrum supporting lever mounted on a xed pivot on which lever the floating lever is fulcrumed, locking devices for locking the fulcrum supporting lever frommovement, a connection from the locking devices to the end of the fulcrum supporting lever remote from its pivot, means for actuating the locking devices to lock and release the fulcrum supporting lever during each stitch forming cycle, a spring acting on the connections between the cam and the presser foot to press the foot toward the work support while the fulcrum is released, a cam actuated lever having an arm formed with an arcuate slot, a link pivotally connected at one end to thel iloating lever and adjustably connected to the slotted arm of the cam actuated lever, and means for stopping the movement of the fulcrum supporting lever while released in a position in which the point of pivotal connection of said link with the oating lever is concentric with the arcuate slot in the cam actuated lever.

13. An outsole shoe stitching machine having,

in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism comprising a presser foot lever on which the presser foot is mounted, an actuating cam, connections between the cam and the presser foot lever comprising a floating lever, a fulcrum support on which the floating lever is fulcrumed, locking devices for locking the fulcrum support from movement, means for actuating the locking devices to lock and release the fulcrum support during each stitch forming cycle, and a spring acting on the connections between the cam and the presser foot to press the foot towards the work support while the fulcrum support is released, said locking devices comprising a wedge member connected to the fulcrum support, a series of rolls for locking the wedge member, and a lock box within which the wedge member and rolls are contained with the series arranged in substantially vertical position with the weight of one roll acting directly on the roll beneath.

14. An outsole shoe stitching machine havingI in combination, stitch forming devices, a work support, a presser foot, presser foot actuating mechanism comprising a presser foot lever on which the presser foot is mounted, an actuating cam, connections between the cam and the presser foot lever comprising a floating lever, a fulcrum supporting lever on which the floating lever is fulcrumed, locking devices for locking the fulcrum supporting lever from movement, means for actuating the locking devices to lock and release the fulcrum supporting lever during each stitch forming cycle, and a spring acting on the connections between the cam and the presser foot to press the foot towards the work support while the fulcrum is released, the oating lever and the fulcrum supporting lever having arms disposed side by side in the direction of the seam line with the arm of the floating lever connected to the presser foot lever and the arm of the fulcrum supporting lever connected to the locking devices.

FRED ASHWORTH. CARL F. WHITAKER.

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