US2197663A - Shoe sewing machine - Google Patents

Description

A 16, 1940. F. BIK EALL snore: SEWING ca ms: Filed m. 25, 1957 4 Sheets-Sheet 1 April16, 1940. F, .5, KEALL 2,197,663

SHOE SEWING MACHINE Filed Aug. 25,1937 4 Sheets-Sheet 2 (IttornegS as v I Zmnentor April16, 1940. F, B, KEA'LL 2,197,663

snon sswme' ncamfi Filed Aug. 25, 19,371 4 Sheets-Sheet s I I 3mentor yaw 4 attornegs F. B; KE A LL snot: spwme MACHINE Filed Aug. 25, 1937 4Sheets-Sheet 4 Inventor KZM Patented Apr. 16, 1940 UNITED "STATES SHOE SEWING MACHINE- Frank Bycroft .Keall, Leicester, England, assignor to United Shoe Borough of Flemington, N. J.,

New Jersey Application "August 25,

Machinery Corporation,

a corporation of 1937, Serial No. 160,737 I In Great Britain September 11, 1936 24 Claims.

This invention relates to sewing machines or mechanisms for use therein, and is particularly,

but by no means exclusively,concerned with sew ing machines, for sewing together the upper and .5 sole of a boot or shoe by a seam which passes from the outer face of the sole to the inside of the boot or shoe. Machines for this purpose, an

example of which is disclosed in the Patent to Richardson No. 710,612 dated October7, 1902, have hitherto, by reason of peculiarities in their construction, usually been capable of being driven only at comparatively slow speeds This is apparently due, to a certain extent, to the fact that the mechanisms which operate the stitch forming and work feeding devices tend to develop excessive wear or vibration if it is attempted to run the machines at relatively high speeds.

One of the: various objects of the present invention is to provide a sewing machine of novel construction for sewing together an upper and a sole of a boot or shoe by a seam as above referred to, which may be operated at comparatively high speed without excessive vibration or wear developing therein and with the'achieve.- ment of thisyobject in view there are provided in an illustrative embodiment of the present invention hereinafter described needle operating and work feed mechanisms which are constructed in such manner as to enable them to be driven at comparatively high speed without undue noise and wear of the parts.

In the illustrative embodiment a I straighthooked needle reciprocating mechanism is provided which is operated by 'a crank and by a plurality of links and levers which are. so relatively arranged as to allow the needle to move at a comparatively high speed at certain times in a machine cycle and yet to allow the needle to dwell at the top of its stroke while the work is being fed and at the bottom of its stroke while the thread is being placedin the hook of the needle. Also, in the illustrative embodiment the work feeding mechanism is operated by ,a crank and a plurality of links and levers arranged vto operate the feed device of the machine at a relatively high speed and yet to provide a dwell in the movement of the feed device while.

in section, showing particularly part of l a work feed mechanism of the illustrative embodiment; Figure 4 is a section on the line IV.IV in Figure 3; Figure 5 is a right hand side elevation,

partly in section, of part of a needle actuating mechanism of the illustrative embodiment; Figure 6 is a section on the line VL VI in Figure 2; Figure 7 is a detail view infront elevation of part of the work feedmechanism; Figure 8 is a section on the line VIlIVIII inFigure 2; and Figure 9 is a, front elevation showing some of the parts of the needle actuating mechanismof the illustrative embodiment in the relative positions they occupy when the needle is at the bottom of its movement.

In the "said illustrative embodiment a vertical needle-bar I is reciprocated upwardly and downwardly by mechanism connecting the needle-bar I ma crank pin 3 on a horizontal forwardly and 'rearwardly extending cam shaft 5 of the machine. The needle bar I has secured on its forward side a pin 7, as shown in Figures 2 and 9. Rotatably mounted on the pin 1 is a bell-crank lever 9. extends upwardly from-the pivot 'lof the lever and this arm is aboutjtwice as long as the other arm l3 of the bell-crank lever which latter arm extends to the left from the pivot? of the bellcrank lever more or less perpendicularly to the longer arm II. The shorter arm it of the bellcrank lever is connected by a radius link iii to a needle adjusting shaft ll 'rotatably mounted in bearings on the machine frame. The arm ll of the bell-crank lever 9 ,is pivotally connected at its upper end by a pin Hi to the lower end of an arm 2l pivotally mountedon a spindle 23 secured in the machine frame. The arm 2| has pivotally, connected to it at '24,, one end of a link 25 which at its lower end is pivotally connected at 26 to the upper end of a curved arm 21.. The-lower end portioniof the curved arm 21 is pivoted at its lower end on a. shaft 29 carried by a needle adjusting arm 3| which is secured on the needle adjusting shaft H and extends towards the left from the needle adjusting shaft to its connection with the curved arm 21. The curved arm Zlhas pivoted to it by a pin 33 one end of a link 35, the other end of which is pivotally connected to the crank pin 3 on the cam shaft 5. I As the cam shaft 5 is rotated, the curved arm 21 is swung, by its connection to the crank pin 3, about its pivot shaft 29 in the needle adjusting arm 3L The swinging movement of the curved arm 21 causes, through the link- 25 connecting the curved arm and the arm ZI to which the longer arm H ofithe aforesaidbell-crank lever9 is connected, up and down oscillating movements to the latter arm Zhwhich arm imparts bodily up and down movements and an One arm I l of the bell-crank lever 9 oscillating movement about its pivot pin I on the needle-bar to the bell-crank lever 9. The up and down movements of the bell-crank lever 9 are transmitted to the needle-bar I by the pin I on the needle bar on which the bell-crank lever 9 is pivoted. The actual up and down"movements of the axis of. the bell-crank lever 9 are controlled partly by the arm 2| to which the longer arm II of the bell-crank lever 9 is connected and partly by the link I5 to which the shorter arm I3 of the bell-crank lever 9 is connected, the relative arrangement of these parts being such that the pivot pin 1 on the needle bar for the bell-crank lever is constrained tomove up and down in substantially a straight line with the result that little, if any, side thrust or twist is imparted to the needle bar I durin its up and down movements.

The relative lengths and angular dispositions of the parts are such that when the needle-bar is at the top of its upward movement the axes of the cam shaft 5, the' crank pin 3 on the cam shaft and the pivot 33 connecting the link 35 to the curved arm 21 are lying substantially on a line extending upwardly and towards the left from the axis of the cam shaft 5'at an angle of about thirty degrees to the horizontal. When the crank pin is in this line, it may be said to be on a'dead center and as the crank pin 3 approaches and leaves this line it imparts little or no movement to the needle bar I, since little or no endwise movement is then imparted to the link 35, which actually dwells at the top of its upward movement during about degrees of rotation of the cam shaft 5. Also when the needle bar is at the top of its upward movement the axis of the shaft 29 on which the curved arm 21 is pivoted and the axes of pivotal connections 26' and 25 all lie substantially on a line passing upwardly and towards the right, at the left hand side of the cam shaft,'at an angle of some sixty degrees to the horizontal and as the needle bar approaches and leaves its uppermost position the axis of the pivotal connection 26 between the curved arm 2'! and link 25 moves across this line. There are, therefore, in the needle bar actuating mechanism, two toggle-like devices (constituted respectively by the crank 3 and the link 35 connecting it to the curved arm 21 on the one hand and the curved arm 21 and the link 25 connecting the latter to the arm 2| on the other hand) which as the needle-bar is approaching and leaving the top of its upward movement are straightening and breaking and therefore at this time imparting little, if any, movement to the needle bar I so that the latter dwells at the top of its upward movement shown in Figure 1.

When the needle bar I is at the bottom of its downward movement (Figure 9) the crank pin 3 is on a dead center at the opposite side (i. e. the right hand side) of the cam shaft 5, the axes of the cam shaft 5, crank pin 3, and the pin 33 being again substantially in the same plane, further when the needle bar I is at the bottom of its downward movement the axes of the bell crank lever 3, the pin l9 and the pivot 23 of the arm 2| also lie substantially on, a line extending through the axis of the cam shaft downwardly and towards the left at an angle of about seventy degrees to the horizontal and also the axes of the bell crank lever 9, the pin connecting the shorter arm 5 of the bell crank lever to its link I5 and the axis of the aforesaid needle adjusting shaft. I! lie substantially on a line extending, just below the cam shaft, at about twenty degrees to the horizontal downwardly and towards the right with resultthat the needle bar dwells at the bottom of its'downward movement and this dwell continues during about 90 degrees of rotation of the cam shaft 5. The fact that the needlebar dwells for so long a period at the bottom of its stroke provides ample opportunity for the thread to be laid in the hook of the needle by a whirl of usual type enclosed within the upper end. of a work-supporting horn 36.

The position heightwise of the needle bar relatively to the work supporting horn 35 of the machine, when the needle bar is at the top of its upward movement, is determined by the height- Wise position of a presser bar 31, similar to that referred to' as 5|, in the Richardson patent.- 'If, when the needle bar I is at the top of its upward movement or is approaching or leaving that position the aforementioned needle adjusting arm 3| is swung about the axis of the needle adjusting shaft I! in a clockwise direction (viewing the machine from the front) the needle bar- I is,

' owing to the relative positions of the various 3| does not, owing tothe relative positions of the parts of the needle bar driving mechanism at 0 these times, affect the heightwise position of the needle bar owing to'the' axes 23, I9 and above mentioned and the axes of the pivots 33,

I! and 29 being also substantially in line at this time. The needle adjusting arm 3| is swung in a clockwise direction by a'cam arm 39 'pivotally mounted on and depending from the needle adjusting shaft l1 and connected to the arm 3| as hereinafter described. The cam" arm 39 has formed on its right hand side a curved face 4| which is engaged by a roll 43 on one arm 45 of a presser bar lever 47 which is secured on the forward end of a horizontal forwardly-and'rearwardly extending shaft 49 rotatably mounted in the machine frame. Another arm 5| of the presser bar lever 4! is connected to the presser bar 31 by a member 53 pivoted at 55 to the arm 5| and having pivoted onv itafblock 5'! which is engaged by a recess formed inthe presser bar. The

member 53 has threaded in it two screws 59 which engage the arm 5| andwhich inay be adjusted to swing the member 53 about the pivot 55' and thus raise or lower the presser bar relatively to the arm 5|. the needle at the top of its stroke is controlled by the heightwise position of the presser, adjustment of the presser bar by means of the screws 59 varies theheightwise position of the needle bar at the top of its stroke relatively to the work. The presser bar 31 is urged down-'- wardly by a spring (not shown) coiled round the presser bar lever shaft'49. The aforesaid cam arm 39 is connected to the needle adjusting arm 3| in such amanne-r, as will hereinafter appear, that when the presser bar 31 is lifted by means or" treadle operated mechanism to; allow- Since the heightwise position of wise by the work, the position of the needle bar, when at the top of its upward movement, is determined, owing to the consequent movement of the said roll 43 towards the right, by the heightwise position of the presser bar according to the thickness of the work on the work supporting horn 38 of the machine. The mechanism therefore acts to cause the needle, at the upper limit of its movement, to occupy a constant position above the upper face of the work whatever he the thickness of the latter.

The presser bar lever 41 and the needle ad justing arm 3| are connected together by stirrup member 6| which has formed in it a slot 63. The right hand end of the slot 63 normally engages a pin 65 secured .in the arm d5 of the presser bar lever 41. The opposite end of the stirrup member 6| has threaded into it a screw 61 which projects into the slot'63 and extends lengthwise thereof. When the presser foot 69 is pressing against the work the screw 5'! is in engagement with a rectangular block H which is pivoted on a plate 73 secured on the needle adjusting arm 3| and engages in the slot 63 in the stirrup member 6|, this blockfll, together with the pin 65 on the presser bar lever arm supporting the stirrup member 5|. The pin 55 on the presser bar lever arm 45 at this time engages the right end of the slot 63. The stirrup member 6| ensures that, after the presser bar lever 41 and needle adjusting arm 3| have been moved simultaneously by the raising of the presser bar 31 by the treadle, the needle adjusting arm 3| will be returnd when the presser bar is allowed to descend again and the slot 63 in the stirrup member 8| allows the presser bar lever 4'! to move relatively to the needle adjust-'- ing arm 3| when the presser bar is raised auto-- matically during each machine cycle to allow the work to be fed.

When the presser bar is raised during the operation of the machine to allow the work to be fed, the needle bar is approaching the top of its upward movement and unless means are provided to prevent the needle bar from being given a small upward movement by the lifting of the presser bar the needle bar will be given an unnecessary and undesirable upward movement during each cycle of the machine. In the illustrative embodiment means is provided which allows the needle bar to be lifted when the presser bar 31 is raised by the treadle operated means but prevents the needle bar I from being lifted when the presser bar 3'! is raised during the operation of the machine to allow the Work to be fed. The said means comprises a connection between the aforesaid cam arm 39 and the aforesaid needle adjusting arm 3| which connection acts when the presser bar 3? is raised by the treadle to cause the cam arm 39 and needle adjusting arm 3| to move together as a unit so that the needle bar is then raised. When the presser bar 31 is raised during the operation of the machine to allow the work to be fed the connection between the cam 39 and the needle adjusting arm 3| is caused to collapse with the result that the cam arm 38 moves relatively to the needle adjusting arm 3| without moving the latter so that the needle bar the ball-end of which is rotatably mounted in a seating in the cam arm 39. The lower end of the arm 15 is secured to the forward part of a rearwardly and upwardly inclined shaft 19 positioned below theneedle adjusting shaft H. The inclined shaft 19 has rotatably mounted on its forward end a'rectangular block 8| which engages a substantially vertical guideway 83 (Figure 2) formed between lugs extending rearwardly from the plate 13 on the'needle adjusting arm 3|. The forward end of the inclined shaft '19 is supported by the short arm l5 (Figure 5) secured on the forward part of the shaft. The rear portion of the inclined shaft 19 is rotatably mounted in the lower "end of an arm 85 secured on and depending from the needle ad it a cam roll 95 which enters a cam groove in a a Y cam, indicated at 3i, secured on the cam shaft 5; The presser cam lever 93, as described in said patent, is coupled during each cycle of the machine, to the presser bar and is operated to cause the presser bar to be raised during each cycle while the work is being fed. When the machine stops, at which time the presser bar may be raised by the treadle operated means, the presser cam lever 93 is so positioned byv its cam that the axis of the universal coupling cohnecting the link 9| to the arm 81 on the in clined shaft 19 is in alignment with the axis of the needle adjusting shaft ll. When, therefore, the needle adjusting shaft I? is rotated in a'clockwise direction through the presser bar lever 41, cam arm 39, arm l5, shaft 19 and arms 3| and 85 by the raising of the presser on depression of the treadle, the inclined shaft 19 is, by reason of its connection to the needle adjus ing shaft ll, carried bodily round the needle adjusting shaft |'l', thus rocking the needle ad justing arm 3|, without being rotated about its own axis, and the'needle bar, then inits fully raised position, will be raised further. When the presser bar is allowed to descend on to the work its heightwise position and the heightwise position of the needle when at the top of its upward movement are controlled by the work. When thepresser cam lever 93 is actuated by cam 97 during the operation of the machine to raise the presser bar while the work is being fed the aforesaid cam arm 39 is, by its connection (including the arm 45 and roll 43) to the presser bar, swung about the needle shaft 6's in a clockwise direction. At" the same time that the presser cam lever 93 raises the presser italso,

the pin 11, the cam arm 35!, which is freely pivoted on the needle adjusting shaft H, in advance of the aforesaid roll 43 on the arm. d5 of the presser lever 41' without moving the arm 3! and needle adjusting shaft 11;

The needle adjusting shaft-l1 has secured to it an arm 99 which extends from the needle adjusting shaft over the cam shaft in towards the right hand sideof the machine and which has pivoted to its right hand end by pin H a link Hi3 which extends downwardly from the arm and is pivotally connected at its lower end to the upper end of a vertical ratchet bar I05 slidingly mounted in the machine frame. The ratchet bar I95 on its rear face has formed on it a series of ratchet teeth I01 which are engaged by the upper end of a pawl I39 pivoted between its ends on a horizontal stud III secured in the machine frame. When the pawl I99 is in engagement with one of the ratchet teeth I01 downward movement of the ratchet bar I05 is positively prevented and, owing to the connection of the ratchet bar to the needle adjusting shaft I1, rotation of that shaft in a clockwise direction and consequent raising of the needlebar I are prevented. The lower end of the pawl I09 has pivotally connected to it the forward end of a link II3 which, at its rear end, is pivotally connected to a cam lever I I5 (similar to the lever referred to as 91 in said patent) which as described in said specification causes the.

presser bar 31 to be connected to its lifting cam lever 93 during the operation of the machine. When the cam lever I I 5 is moved by its cam, indicated at II1 Figure 5, on the cam shaft 5 in a direction to cause the presser bar 31 to be connected to its lifting cam lever 93 prior to the raising of the presser bar, the pawl IE9 is moved into engagement with one of the ratchet teeth I I11. The ratchet bar I05 has secured in its right hand side a horizontal pin II9 which is engaged by a substantially horizontal recess IZI formed in the rear end of a substantially horizontal lever I23 pivoted on a horizontal stud I25 secured in the machine frame. The forward end of the Y lever I23 is rounded and enters a recess formed in the right hand side of a vertical plate I21 (Figures l and 2) at the front of the presser bar 31. The vertical plate I 21 is guided vertically by a stud I29 (corresponding to the screw-pin referred to as 56 in said patent) secured in the machine frame and passing through a vertical slot I3I in the upper end of the plate and a stud I33 (Figure 6) secured in the presser bar which passes through another vertical slot I35 in the plate near its lower end.

The vertical plate I21 has rotatably mounted in it, near its lower end a horizontal extending pin I31. The pin I31 extends rearwardly from the plate and passes through a vertical slot I39 in the presser bar 31. The pin I31 has secured at its rear end a rectangular block I II (Figures 2 and '1) which enters an inclined guideway I43, extending downwardly towards the left, formed in a feed point carrier I 45. The feed point carrier I lies just behind the presser bar 31 and is guided by the rectangular block I4I and by a pin I41 extending rearwardly from the presser bar 31 which is engaged by an open ended slot I .49 in the upper end of the feed point carrier I45. Freely pivoted on the lower end of the feed point carrier, on a pin I5I, is a depending feed point arm I53 in the lower end of which a feed point I55 is secured, the relative positions of the feed point I55 and the presser bar 31 being similar to those indicated in the patent aforementioned. The feed point arm I 53 is normally drawn towards the right into contact with the presser foot 69 by a tension spring I51 connected at one end to the feed point arm I53 and at the other end to the presser bar 31. The feed point arm I53 has secured in it between its pivot and its feed point a rearwardly extending pin I59, to which one end of the spring I51 is connected, and the feed point carrier I45 has formed in its left hand side near its lower end a recess I5I arranged, during movement of the feed point carrier I45 in the direction of work feed, to engage the pin I59. When the lower end of the feed point carrier I45 is moved towards the left, by mechanism hereinafter described, in a direction to feed the work, the lower end of the feed point carrier is guided downwardly and towards the left by the aforesaid block MI in the inclined guideway I43 in the feed point carrier I45. During the early part of the movement of the feed point carrier I45, the feed point arm I53 is held by the aforementioned spring I51 against the presser foot 69 and the feed point descends more or less vertically into the work. When the recess I6I in the feed point carrier I45 engages the pin I59 in the feed point arm I53, the feed point arm I53 and feed point I55 then engaging in the work move with the feed point carrier I45 and the feed point feeds the work, the feed point carrier I45 being guided by the block I4! on the vertical plate and the aforesaid pin I41 on the presser bar 31. The block MI and the pin I41 are so relatively arranged that when the feed pointv I55 is feeding the work its lower end moves substantially horizontally towards the left. At the time in the machine cycle when the presser bar 31 is raised to allow 1 the feed point from rising from the lowest position which it reached in digging into the work preparatory to feeding it. Since the ratchet bar IE5 is, as hereinbefore described, secured on the aforesaid needle adjusting shaft I1, the needle shaft is prevented from being rotatedin a clockwise direction and the needle-bar is therefore prevented, by the pawl and ratchet teeth, from being raised by the lifting of the presser bar which takes place to allow the work to be fed by the feed point.

The pawl I09 preferably engages the ratchet teeth I91 during the greater part of the machine cycle, being released therefrom after the work is fed only about long enough to allow the needle mechanism to accommodate itself to the heightwise position of the presser after the latter has been allowed to descend on to the work after the work has been fed. The pawl and ratchet teeth therefore prevent any tendency there may be to overthrow during the movement of the needlebar, at other times in the machine cycle, due to the. momentum of the parts. I

The aforesaid mechanism for moving the feed point carrier I45 towards the left to feed the work comprises a crank and a plurality of links and levers the shafts and pivot pins of which all extend horizontally forwardly and rearwardly of the machine and the mechanism. includes a substantially horizontal link I1I which at its right hand end is connected to the pin I5! and at its left hand end is pivotally connected to the lower end of one arm of a bell-crank lever I13 which is pivoted on a pin I15 secured in a depending arm I11 of a second bell-crank lever I19. The bellcrank lever I13 has an upwardly extending arm I8! the upper end of which lies at a lower level than the cam shaft 5 aforementioned and the upper end of the arm has mounted on it a cam roll. I83 which is held by a spring against the underside of a cam I85 on the forward end of the cam shaft 5, this cam-serving to rock the bell-crank lever I13 about its pivot I15 on the bell-:crank lever I19. The bell-crank lever I19 is p iyoteg 3) which extends towards the rightfromthe hub of the lever. The arm I89 of the bell-crank lever I19 has pivoted to its right hand end one end of a link I9I which extends upwardly and towards the right and at its upper end is pivotally connected to one end of a. feed adjusting lever I93. The feed adjusting leverI93. extendsupwardly and to the left from its connection to the link IBI and at its left hand end is pivoted on a crank pin. I95 which maybe adjusted to alter the position in the-machine of the left hand end of the feed adjusting lever I93 and may be locked in its adjusted position so that the crank pin' I95 provides a fixed but adjustable pivot for, the left hand endof the feed adjusting lever I95. Thecrank pin I95. extends. forwardly from an arm I96 secured on a crank shaft I91, rotatablyv mounted in the machine frame, which is angularly adjustable to vary the position of the crank pin I95 in the machine frame. The crank shaft I91 has secured on its rear endan arm I99 (Figure 4) by which the crank shaft may be rotated. The arm I99 extends towards the right 'handside of the machine and its right hand end carries a clamping device by which the arm may-be clamped in adjusted position to a plate 2M secured on the machine frame. The clamping device comprises a-bolt 203 extending through the arm I99 and through a block 205. of it a head 201 which engages the'block 205 and on its other and threaded end a hand nut 209 by means of which'the block 205 andarm I99 may be clamped against the plate 2III. The hand nut 209- may be used to swing the arm I99 and crank pin I95 upwardly or downwardly. The feed adjusti'n'g lever I93 is pivot ally connectedat ZII, between its ends, to one end of a link 2 I3 which extends downwardly and to the left from the feed adjusting lever and at its other end is pivotally connected, at 2I5, to a depending arm of a'bell-crank lever, 2 I1 which is secured on a shaft 2I9." rotatably mounted in the machine frame. The other arm of the bell-crank lever 2 I1 extends upwardly andto the left from the hub of the lever and has'pivotally connected to its upper end, at22I, one end of a link 223' the other end of which is pivotally connected,. at 225, to the right hand end of a crank lever 221. The left 1 hand end of the crank lever 221 is pivoted on a crank 229 on" the'cam shaft and between its endsthe crank lever is pivotally connected at '23 I,

to the upper end of a radius arm 233 which serves to, control the direction of movement of the right hand end of the crank lever 221 as the cam shaft rotates. The radius arm 221 is secured at its lower end on a shaft 235 which is rotatably mounted in the machine frame below and just to theright of the cam shaft. As thecam shaft 5 rotates the right hand end of the crank. lever 221i is caused, by the crank 229 and radius arm 233', to move in more or less elliptical path,'indicated by thedot-and-dash line 231 Figure 3, one side or which is during the movement of the right hand end of the crank lever 221 along it concentric to the pivot 22I connecting the link 223-,to-the bell-crank lever ZITa-nd therefore during this part vof the movement of the right hand end of thecranklever .221 no endwise movement is imparted to the link 223 and no feed movement is imparted to the feed point through the crank lever 221, the feed point dwelling,v after it has hecome nsbdde the w r lth ush, Che

The bolt has on one end ing of the bell-crank lever I13 both while the needle is piercing the work and while it is moving upwardly witha loop of thread in its hook. When the right hand end of the crank lever 221 is moving'along the opposite side of its elliptical path 231 it imparts appreciable endwise movements to the link 223 connected to it and feeding and return movements are, during, this part of the movement of the crank lever 221', given to the feed point. the feed adjusting lever. I93 is pivoted, is adjusted in such a manner as to move the pivot iii 5 connecting the feed adjusting lever I93 and the link 2 i3 nearer to or further away from the the amount of movement imparted tothe feed point.

The dot and dash line a in Figure B indicates the'path of movement of the axis of the pivot H I I when the crank pin I95 is adjusted, in a counterclockwise direction, to reduce the length of feed ing movement of the work. The line b indicates the position of the axis of the pivot 2 at the end of the different lengths of feeding. movement of the feed point and the lines o of different length indicate the distances the axis moves dur ing different lengths of 'feeding movement of the feedpoint'. a

The cam I85 on the cam shaft 5 which actuates the bell-crank lever I13 causes the feed point I55, after the work has been fed and the feed point has been returned towards the right, tobe moved downwardly intoengagementwith the work and to be held there during the aforementione'd' dwell of the feed'point.

During the feed of. the work, the bell-crank lever I13 iscarried bodily towards the left' by the swinging movement of the bell-crank lever I1 9 and the cam roll I83 on the bellcrank lever I13 moving idly under its cam. As'the feed point is reaching the end of its return movement towards the right, during which it tra-ils along on the work and is being thus'moved by thev crank 229 and link mechanism while the cam roll I 83on the bell-crank lever I13 moves to the right with thebell-crank lever I19 idly beneath raised is effected by the conjoint action of the crank 229 and the cam I85 which act simultaneously to movethe feed point carrier I45 towards the-right. After the feed point carrier I45 has been moved to the right far enough'to raise the feed point above the work the mechanism operated by the crank 229 dwells as aforesaid and the cam I85 moves the feed point carrier sufficientlyfar towards the left to cause the feed point to move downwardly into engagement with the work in readiness again to feed the work. The cam operated mechanism and the bell-crank lever I13 then dwell while the needle passes through the work and rises therefrom with a loop of thread in its hook.

A sewing machine] provided with the mechanisms hereinbefore described for actuating and.

If. the; crank pin I95, on which controlling the needle bar and workfeed point 7 is capable of being operated at comparatively high speed without undue noise or vibration, the raising of the presser foot independently of the feed point ensuring that the feed point firmly engages with the work and feeds the work the full distance through which the feed point moves during its feeding movement.

In the illustrative embodiment a cast-off mechanism is provided which is substantially similar to the cast-off mechanism described in Patent Nb. 1,713,186 to Bernard T. Leveque dated May 14, 1929, and operates in a similar manner. The cast-off 24! is mounted to slide in a vertical groove in the right hand side of the needle bar I and is secured at its upper end in a collar 263 mounted to slide vertically on the needle bar between blocks 245, 24'! secured on the needle bar I above and below the collar 243. The collar 253 has secured in it a forwardly extending pin on which is rotatably mounted a roll 249 which as the needle bar moves up and down passes between the upper inwardly inclined ends of a pair of levers 25!, 253 similar to the levers referred to as 12, 14 in the latter specification which are normally urged towards each other by a spring 255 similar to the spring referred-to as 76 in said specification. In the illustrative embodiment the levers 25!, 253 are pivoted on a block 25'! which is pivotedon a horizontal forwardly and rearwardly extending stud 259 secured in a bracket 26! which is fixed to the machine frame. The stud 259 is positioned a little below and centrally between the pivots 263, 265 of the levers25l, 253. The block 25'! has extending to the left from it an arm 25'! on which is secured a blade spring 269 which extends towards the left from the block and its left hand end extends between two pins 21!, one above and the.

other below the spring, which are secured in ,an arm 213 projecting from the bracket 26! and which hold the left hand end of the spring from upward or downward movement but allow. it .to move lengthwise between them. The spring 255 is arranged to normally hold the levers in a central position with respect to the needle bar. The pivotal mounting of the block 25'! on which the levers 25!, 253 are pivoted and the blade spring 269 allow the levers to rock bodily to the right or left of the needle bar should it, during its upward or downward movement, be turned about its axis and thus enables the roll 249 on the collar 243 to bear equally uponv the inclined upper faces of the levers.

, The nature and scope of the invention having been indicated, and a machine embodying the several features of the invention having been specifically described, what is claimed is:

1. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a rotating crank, lever and link connections between thev crank and needle for 1 actuating the needle from the crank. a support upon which one of the levers is mounted movable to varyithe stroke of the needle, a presser foot, connections between the support and the presser foot for adjusting the support for different thicknesses of work, mechanism for lifting the presser foot during each stitch forming cycle, and means actuated by said mechanism for rendering the connections between the presser foot and said support inoperative to move the support as the presser foot is lifted by said mechanism. 2. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a rotating crank, lever and 'link connections between the crank and needle for actuating theneedle from the crank, a'support upon which one of the levers is mounted movable to vary'the stroke of the needle, a presser foot, connections between the support and the presser foot for adjusting the support for different thicknesses of work, mechanism for lifting the presser foot during each stitch forming cycle, and means for preventing movement of said support by the presser foot as the presser foot is lifted by said mechanism.

3. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a rotating crank, lever and link connections between the crank and needle for actuating the needle from the crank, a support upon which one of the levers is mounted movableto vary the stroke of the needle, a presser foot, connections between the support and the presser foot for adjusting the support for different thicknesses of work, and for moving the support to.

raise the needle when the presser foot is raised for the removal or insertion of work, mechanism for lifting the presser foot during each stitch forming cycle, and means for preventing movement of said support by the presser foot as the presser foot is lifted by said mechanism.

,4. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a rotating crank, lever and link connections between the crank and needle for actuating the needle from the crank, a support, upon which one of the levers is mounted movable to vary the stroke of the needle, a needle adjusting shaft to which the support is secured, an actuating arm pivotally mounted on the needle adjusting shaft, an arm rigidly mounted on the shaft, a rotatable shaft supported in the rigidly mounted arm, and in the support, an arm rigid with the rotatable shaft and pivotally connected with the actuating arm, a presser foot, connections from the presser foot for moving the actuating arm to adjust the needle adjusting shaft and support for dififerent thicknesses of work, mechanism for lifting the presser foot during each stitch forming cycle, and means actuated by which one of the levers is mounted movable to vary the stroke of the needle, a presser foot, and connections between the support and the presser foot for adjusting the support for different thicknessesof ork, comprising a presser foot bar, a lever having one end engaging the support, and

a block adjustably mounted on the other end of the lever and engaging the presser foot bar.

6. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a rotatingcrank, lever and link connections between the crankand needle for actuating'the needle from the crank, a support upon which one of the levers is mounted movable to vary the strokeof the needle, a presser foot, and connections between the support and the presser foot for adjusting the support for different thicknesses of work comprising a presser foot bar, a

lever having one end engaging-the support, and

means adjustably connecting the presser foot bar and the other end of the lever.

7. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a single rotating crank, and connections between the crank and needle for actuating the needle comprising levers and links arranged to form two toggles, one of which is substantially' straight when the needle is at the top of its stroke'and while the crank is passing overone dead center, and the other of which is substantially straight when the needle is at the bottom of its stroke and the crank is passing over the other dead center.

8. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a rotating crank, and connections between the crank and needle for actuating the needle comprising a lever, a link connecting the crank and lever, a bell crank, a link connecting the lever and bell crank and forming a toggle with the lever, and a link connecting the bell crank to the needle and forming a toggle with the bell crank, the first mentioned toggle being straightened when the needle is at the top of its stroke, and while the crank is passing over one dead center and the other toggle being straightened when the needle is at the bottom of its stroke and while the crank is passing over the other dead center. I

9. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a horn arranged to extend within the shoe, means for actuating the needle to pierce and withdraw from the work, a presser foot, a feed point carrier movable back and forth in the line of feed, a feed point pivotally mounted on the carrier and arranged to slideon the presser foot into engagement with the work at the beginning of the forward movement of the carrier and out of engagement with the work at the end of the backword movement of the carrier, and a support forthe feed point carrier separate from the presser foot arranged to permit the presser foot to be lifted without lifting the carrier. I H

10. A shoe sewing machine having, in combination, stitch forming devices, a straight hook needle, a horn arranged toextend within the shoe, means for actuating the needle to pierce and withdraw from the work, a presser foot, a feed point carrier movable back and forth in the line of feed, a feed point pivotally mounted on the carrier and arranged to slide on the presser foot into engagement with the work at the beginning of the forward movement of the carrier and out of engagement with the work at the end of the backward movement of the carrier, and means for supporting the feed point carrier while permitting a lifting movement of the presser foot without lifting the carrier. v

11. A shoe sewing machine having, in combina tion, stitch forming devices, a straight hook needle, a horn arranged to extend within the shoe, means for actuating the needle to pierce and-withdraw from the work, a presser foot, a feed point carrier movable back and forth in the line of feed, a feed point pivotally mounted on the carrier and arranged to slide on the presser foot into engagement with the work at the beginning of the forward movement of the carrier and out of engagement with the work at the end of the backward movement of the carrier, mechanism for actuating the feed point carrier and presser foot arranged to cause the feed point to enter the work before the presser foot is raised and to raise the presser foot while the feed point is engaged with the work without raising the feed point carrier. f Y

12. 'A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a horn arranged to extend within the shoe, means for actuating the needle to pierce and withdrawfrom the Work, a presser foot, 2. feed point carrier movable back and forth in the line of feed, a feed point mounted on the carrier, means comprising a cam for actuating the feed point carrier to cause the feed point. to engage the work, and means comprising a crank for actuating thefeed point carrier to cause the feed point to. feed the Work.

13. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a horn arrange-d to extend within the shoe, means for actuating the needle to pierce and withdraw from the work, a presserfoot, a feed'point carrier movable back and forth in the line of feed, a feed point mounted on the carrier, and means for actuating the feed, point carrier comprising a radius arm, a crank actuated lever pivoted on the radius arm, a crank engaging one end of the lever, a link pivotally connected to the other end of the lever, and an actuating lever to which the link is connected, sai-dparts being arranged to cause a to-and-fro oscillation of the actuating lever during a portion of the crank rotation, and during the remainder of the crank rotation to. maintain the actuating lever stationary..

1,4. A shoe sewing machine having, in combination,- stitch forming devices including a straight hook needle, a horn arranged to extend within the shoe, means for actuating the needle to piece and withdraw from the work, a presser-foot, a feed point carrier movable back and forth in the line of feed, a feed point mounted on the carrier, and means for actuating the feed point carrier comprising a radius arm, a crank actuated lever pivoted on the radius arm, a crank engaging one end of the lever, a link pivotally connected to the other end of the lever, and an acment of the feed point carrier.

15. Ashoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a hornarranged to extend within the shoe, means for actuating the needle to pierce and-withdraw from the work, a presser foot, a feed point carrier movable back and forth in the line of feed, a feed point mounted on the carrier,

and means for actuating the feed point carrier comprising a radius arm, a crank actuated lever pivoted on the radius arm, .a crank-engaging one end of the lever, a link pivotally connected to the other end of the lever, and an actuating lever to which the link is connected, said parts being arranged to cause the pivot connecting the crank actuatedlever and the link during a portion of the crank rotation to be moved back and forth across the line joining the pivot of the crank actuated lever, and the pivot connecting the link with the actuating lever in a path to impart a to-and-fro oscillation to the actuating lever and during another portion of the crank rotation to be moved in a path concentric to said last mentioned pivot to maintain the actuating lever stationary.

16. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a horn arranged to extend within the shoe, means for actuating the needle to pierce and withdraw from the Work, a presser foot, a feed point carrier'movable back and forth in the line of feed, a feed point mounted on the carrier, and means for actuating the feed point carrier comprising a pivotally mounted feed adjusting lever, connections from said lever to the feed point carrier, an actuating lever, a link connecting said levers, and means for adjusting the pivot of the feed adjusting lever to change the relative position of the link and actuating lever.

17. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a horn arranged to extend within the shoe, means for actuating the needle to pierce and withdraw from the work, a presser foot, a feed point carrier movable back and forth in the line of feed, a feed point mounted on the carrier, a lever, connections from the lever to the feed point carrier, a support on which the lever is mounted, a cam for actuating the lever to cause the feed point to engage the work, and a crank and connections for actuating the support with the lever to cause the feed point to feed the work.

18. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a horn arranged to extend within the shoe, means for actuating the needle to pierce and withdraw from the work, a presser foot, a feed point carrier movable back and forth in the line of feed, a feed point mounted on the carrier, and means for actuating the feed point carrier comprising an actuating lever, a crank, a link pivoted at one end to the lever, and connections between the crank and the link arranged to cause the other end of the link, during a portion of the crank rotation, to be moved back and forth in a path concentric with the pivotal connection of the link with the actuating lever, and during another portion of the crank rotation to be moved back and forth in a path to impart a to-and-fro oscillation to the actuating lever.

19. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a horn arranged to extend within the shoe, means for actuating the needle to pierce and Withdraw from the work, apresser foot, a feed point carrier movable back and forth in the line of feed, a feed point mounted on the carrier, a presser foot bar, a support for the feed point carrier mounted to slide on the presser foot bar towards and from the horn, connections between the presser foot and the support for regulating the position of the Support with relation to the horn, and means for preventing movement of the support when the presser foot bar is moved away from the horn to allow the work to be fed.

20. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a horn arranged to extend within the shoe, a rotating crank, lever and link connections between the crank and needle for actuating the needle from the crank, a'support upon which one of the leversis mounted movable to vary the stroke of the needle, a presser-foot, connections between the support and the presserfoot for adjusting the support for different thicknesses of work, a presser foot bar, a feed point carrier movable back and forth in the line of. feed, a feed point mounted on the carrier, a support for the feed point carrier mounted to slide on the presser-foot bar towards and from the horn, and connections between said supports for regulating the position of the feed point car rier support with relation to the horn.

21. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a rotating crank, lever and link connections between the crank and needle for actuating the needle from the crank, a support upon which one of the levers is mounted movable to vary the stroke of the needle, 2. presser foot, connections between the support and the presser foot for adjustably limiting the movement of the support in one direction to adjust the support for different thicknesses of work, and means acting during a portion of each stitch forming cycle to lock the support against movement in the opposite direction.

22. A shoe sewing machine having, in combination, stitch forming devicesincluding a straight hook needle, a rotating crank, lever and link connections between the crank and needle for actuating the needle from the crank, a support upon which one of the levers is mounted movable to vary the stroke of the needle, a needle adjusting shaft to which the support is secured, a presser foot, connections between the-shaft and the presser foot for adjustably limiting the rotation of the shaft in one direction, afbar connected to the shaft, and cam actuated means for locking the bar against movement during a portion of each stitch forming cycle to limit the rotation of the shaft in the opposite direction.

23. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a cast-01f movable with the needle and'having a limited independent movement, a pin connected to the cast-off, yielding members connected to move inunison towards and from each other between which the pin passes during the needle movement and by which the cast-off is moved with relation to the needle, and a block upon which said members are mounted, said block being mounted for yielding movement transversely of the needle movement to cause the pin to bear equally upon said members.

24. A shoe sewing machine having, in combination, stitch forming devices including a straight hook needle, a cast-off movable with the needle and having a limited independent movement, a pin connected to the cast-off, yielding members between which the pin passes during the needle movement and by which the cast-ofi" is moved with relation to the needle, a pivotally mounted block upon which said members are mounted,

and a spring acting on the'block to hold said members yieldingly in the path of said pin.

FRANK BYCROFT KEALL.

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