US2339240A - Sewing machine - Google Patents

Description

Jam 18, 1944' A. B. CLAYTON 2,339,240

SEWING MACHINE Filed Aug. 29, 1941 7 Sheets-Sheet l,

v vuil/wbb@ Andrew B. Clayton Jam. 18, 1944.. A. B. CLAYTON SEWING MACHINE lf'iled Aug. 29. 1941 B. @hay-fon @www Jan; 18, 1944. A. B. cLAY-roN SEWING MACHINE Filed Aug. 29, 1941' 7 sheets-sheet `s www Ana/mw B. Clayton A. B. cLAY'roN 2; 9,240

SEWING- MACHINE Filed Aug. 29. 1941 'r sheets-sheet 4 Jan. 18, 1944.

I rwwwbe/o Y Anc/reu) B. @loll/fon Jan. 18, 1944- A. s. CLAYTON A 2,339.240

I SEWING MACHINE Filed Aug. l29, .1941 `"r Sheng-sheet 5 l grww f Andrew B. Clayt'on Jain. 1s, 1944.

A B, cLAYToNv 2,339,240 SEWING MACHINE Filed Aug. 29, V1941 7 Sheets-Sheet 6l Witwe 55 Andrew B. @Layton 1m 18, 1944- A B. CLAYTON 2,339,240 SEWING MACHINE' l.

Filed Aug. 29. 1941 7 Sheets-Sheet '7 Andrew B. Clay on A *www Y I I Wy/wf N u;

Patented Jan. 18, 1944 UNITED STATES PATENT OFFICE' Singer Manufacturing Company,

Elizabeth,

N. J., a corporation of New Jersey Application August 29, 1941, Serial No. 408,701

16 Claims. (Cl. 112-207) This invention relates to sewing machines and Ymore particularly to sewing machines having a so-called clamp feeding mechanism, i. e., workfeeding mechanism having synchronously acting feeding elements engaging the `work at opposite faces, and also automatic presser-foot lifting mechanism operated in timed relation with the feeding mechanism.

As heretofore constructed, sewing machines of this type, due to their complexity, Weight of parts, inertia, etc., usually have had a maximum speed in the neighborhood of 3000 stitches per minute.

It is an object of this invention to provide, in -a machine of this type, improved feeding and presser-foot lifting mechanisms which will enable the machine to be operated at a much higher speed than heretofore was possible,v to wit, 4000 stitches or more per minute; which will lighten and render more uniform the load improved upon the driving shaft; and which will operate with a minimum of vibration and noise.

A further object of the invention is to provide a single means for simultaneously adjusting the feeding movement of both the top and bottom feed-dogs, other means for independently varying the feeding stroke of the top feed-dog, and means for varying the lift of the upper feeding foot and the presser-foot which holds the work on the throat-plate during the time that the feeddogs are out of contact with the work.

With the above and other objects in View, as will hereinafter appear, the invention comprises the devices, combinations, and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention, from which the several features of the invention Aand the advantages attained thereby will be readily understood by those skilled in the art.

1n the drawings, Fig. 1 is a front elevation of a two-thread chain-stitch sewing machine embodying the present invention. Fig. 2 is a rear elevation thereof. Fig. 3 is a plan View of the machine shown in Fig. 2. Fig. 4 is an enlarged left end elevation, partly in section, of the machine 6--6 of Fig. 1 illustrating means for hingedly supporting an arm cover-plate and means for locking it in its operative position. Fig. 7 is a fragmentary left end View of the machine shown in Fig 1 with the upper feeding foot, the presserfoot and their actuating mechanisms shown in full and dotted line positions. Fig. 8" is a horizontal sectional View taken substantially on the line 8 8 of Fig. 7. Fig. 9 isa fragmentary rear view of a portion of the sewing machine showing, partly in elevation and partly in section, means for. simultaneously varying the feeding stroke of both the upper and under feed-dogs. Fig. 10 is a detail sectional View through the combined beltand hand-wheel, showing means for indicating the amount of lubricant contained in the hollow main shaft, which lubricant is used to lubricate the needle-bar driving mechanism. Fig. 11 is a right end view, partly in section, of the machine shown in Fig. l.y Fig. 12 is a vertical sectional view taken substantially on the line v|2``I2 of Fig. 11. Fig. 13 is :a detail sectional View taken substantially on the line I3-l3 of Fig. l2 showing the looper-thread take-up cam and the means for adjustably securing it to a belt-sprocketfxed upon the main shaft of the machine.` Figs'. 14 and l5 are diagrammatic views illustrating, in full and dotted lines, the actionof the means for alternately lifting the presser-foot and the upper feeding foot and for transferring to each the spring-pressure normally applied to the other.

` Referring more specificallyv to the drawings, the invention is disclosed as embodied in a sewing machine having a frame comprising a base i, upright standard 2, overhanging arm 3, terminating in a hollow head 4 closed at its forward face by aface-plate 5. The standard is formed with a vertical internal partition 2e (Fig. 12) which extends from the bottom wall of the base l tothe upper wall of the arm 3 and divides the space within the standard into a belt compartment 54 andv a splash-lubrication compartment 54a. This splash lubrication compartment overlies an oil reservoir R in the base l and permits the oil therein to be splashed into contact withthe Working parts therein by the action of a portion of the looper actuating mechanism therein. A transparent plug P'(Fig. Vl) l secured inthe base I and having a vertical bore p in communication with the oil in the reservoir R indicates to the operator the level of the oil in the reservoir. The vbase is formed with upright portions 6, l and 8 (Figs. 1,2an'd 3) which support a work-plate 9, a throat-plate l0, and end and rearclosure-plates Il and l2, respectively.

These elements provide a substantially closed compartment in which is located feeding mechanism later to be described. A guard member or apron I3, hinged on a pin I4 supported by the cloth-plate 9, overlies a portion of the actuating mechanism, designated generally as r, of a chainstitch looper L, and prevents accidental contact therewith.

Journaled lengthwise within the arm 3 is a main or needle-bar actuating shaft I5, having secured to it, at its rear end, by set screws I5',

a combined beltand balance-wheel I6 by means of which the machine may be driven from any suitable source of power. The forward end of the shaft I5 has secured to it a crank-disk I'I carrying a crank-pin I8 connected, by a link I9, with a collar 20, securedjupon a hollow needle-bar 2I reciprocably mounted in the head 4.l At its lower end the needle-bar carries an eyepointed needle 22, which cooperates with the looper L in the formation of stitches. The shaft I5, is preferably hollow and serves as a reservoir for oil for lubricating the needle-bar actuating mechanism as shown and described more fully in my United States Patent No. 2,120,210, July 7, 1938. rThreaded upon therear end of the main shaft, beyond the balancewheel. I6, is a. curved disk 23 (Fig. 10) having its convex surface outward. The disk 234 has a central hollow hub 24 into whichV is inserted a transparent plug 25 having an open endedbore 26 in communication with the lubricant-holding bore 21 in the shaft. Transverse openings 28 formedin the hubY 24 permit the operator to see through the plugV 25 and, thereby ascertain Whether there-issuflicient oi1 in the reservoir in the main shaft.

Thread n for the needlepasses from a suitable sourcev of supplyy through a thread-eye 29X formed in a kink-removing plate 30 (Figs. 1 and 3) secured to a tension-bracket 3l thence around the edge of the plate and back through a thread-eye 29. From the eye 29 the thread extends throughv a tension 32 thence through a self-threading thread-guide 33, thread-nipper 34, back through the thread-guide 33, through a thread-eyeV 35 formed in an adjustable arm 36, secured to the machine arm, through a takeup-3'I, to a thread-eyev 38 formed in a plate 39 adjustablyy secured to the face plate 5, and thence to theeye ofthe needle.

The` looper thread l extends from a suitable source o f` supply to a thread-eye 45X formed in a tension-supporting plate 4I)y thence through a thread tension 40, through a take-up 4I, down through a thread-guiding tube 42, through a thread-guide 43, to the looper L.

The take-up 4I comprises a thread-controlling cam disk 44, adjustably secured to a beltsprocket 45 lixed upon the mainshaft I5. The cam disk 44y is secured to the sprocket 45 by screws-44a which` pass through slots 44b in the disk and are threaded into the sprocket. The cam disk operates through a slotted stripperplate 46y carrying a U-shapedthread-stripper 4l and thread-guides 48,

As shown most clearly in Figs. 11 and 12, the belt-sprocket 45X is frictionally secured upon a sleeve lIS-which, in turn, is secured to the shaft I5 by means of a set-screw 5D and forms a part of adriving connection between the rotary main shaft I5 and arotary looperand lower-feed actuating shaft 5I journaled in bearings provided by the base ofthe machine. The other elements of the driving connection between the two shafts consist of a similar belt-sprocket 52 secured upon the shaft 5i and a connecting clipbelt 53 surrounding the sprockets. The driving connection between the two shafts is located in the compartment 54, formed in the rear portion of the standard 2, which compartment is normally closed by upper and lower cover- plates 55 and 56, respectively, secured to the standard by screws 5'I and 58.

It is sometimes required that the timing of the take-up cam be varied relative to the timing of the looper mechanism. This may readily be effected by adjusting the take-up disk angularly about the axis of the shaft I5. To accomplish this the hand-wheel I6, plate 55, and a cup-like guard element 59 (Fig. 12) which surrounds the shaft I5 and the hub of the sleeve 49 are first removed. After those elements have been removed the screws 44 may be released and the cam-disk rotated slightly about the axis of the shaft after which the screws 44a are again tightened and the guard element, cover-plate and hand-wheelV are replaced.

As shown most clearly in Figs. 1, 11 and 12, the periphery of the take-up disk 44 projects through a slot 4.6a in the take-up stripper plate 46. To prevent dust, lint or other foreign matter from entering the compartment 54 through the slot 45a and also to prevent the end of the thread from passing into theA slot and becoming entangled with or wound about the parts in the compartment 54, should the thread break, means is provided for maintaining, during the operation of the machine, a continuous flow of air outwardly through the slot 45a, as indicated by the arrows in Fig. 12. This is effected by an air pump-preferably in the form of a rotary ian 60 secured to the sprocket 52 on the looperand feed-actuating shaft 5I. During running of the machine the fan 6i), which has radially extending and backwardly inclined varies BI, draws air intotheV compartment 54 through an opening 62 formed in the cover-plate 53, coaxial with the fan, and forces it upwardly and dischar-gesY it through the slot 4ta in the stripperplate 46,`

The roverhanging bracket-arm 3-is hollow as indicated'at c in Figs.. 5 and 6, and has located therein the primary actuating means, later to be described, for alternately lifting a presser-foot 53 and any upper feeding foot 54 also later to be described. For the purpose of permitting entry into the cavity c thereby to give access to the actuating means therein and to a screw-closed lling hole I5X formed in the shaft I5, whereby lubricant may be supplied to the reservoir formed inthe shaft, the upper wall of the arm is cut away to form an opening 55. This opening is normally closed by a cover-plate 6B secured, by screws El, to a bracket 58, loosely hinged at 5G. within a head 'E0 formed at one end of a horizontally disposed bar l! secured in the arm of the machine. Fixed to the under side of the coverplate 66, bymeans of a plate l2 and screws 'I3 (see Fig. 6), is a gasket 'M which eiects an oiltight seal between the cover-plate and the arm 3; The downturned portion of the bracket G8 is formed with a slot 'I5 which is slightly larger than the pivot-screw 59 passing therethrough thereby permitting the bracket and the coverplate carried thereby to float both vertically and horizontally relative to the arm 3 thus insuring complete contact between the gasket i4 and the upper surface of the arm upon which it is seated. To draw the gasket into oil-tight contact with its seatthe cover-plate has journaled therein a vertically disposed pin 1B having, at its upper end, a finger-piece 11 by means of which the pin may be rotated. At its lower end the pin 16 has secured thereto a cam element 18 having an inclined upper surface 18 adapted, upon rotation of the pin, to engage beneath the bar 1I and thus draw the gasket 'I4 and cover-plate 66 into oiltight contact with the arm 3 about the opening 65. One side of the cam element 18 is cut away, as indicated at 18a, in Fig. 3. Thus when the finger-piece is rotated to the position shown in dot-dash lines in that figure, the cutaway portion 18a clears the bar 1I and permits the coverplate B6 to be tipped upwardly as indicated in dotted lines in Fig. 6.

'I'he presser-foot 63, above mentioned, is secured upon the lower end of a presser-bar 19 slidingly mounted in a bushing 80 secured by a screw 8| in the lower portion of the bracket-arm head 4. The presser-bar is normally depressed by a coil-spring 82 fitted within a sleeve 83 secured in the upper portion of the head 4 by a screw 84. As shown most clearly in Fig. 4a, the lower end of the spring 82 bears upon a plug-head 85 which, in turn, bears upon the upper end of the presser-bar. The tension of the spring 82 may be varied, thereby to increase or decrease the pressure transmitted to the presser-foot, by an adjusting screw 8B threaded through the upper end of the sleeve 83 and bearing on a plug-head 81 seated upon the upper end of the spring. The screw 86 may be locked in adjusted position by a clamp-nut 88 threaded thereon and adapted to engage the upper surface of the head 4.

Cooperating with the presser-foot 63 in the feeding of work is a lower four-motioned feeding mechanism including a serrated feed-dog 89 secured, by a screw 90. in the forward free end of a main feed-bar 9| pivotally mounted at its rear end in a feed-rocker 92 and adapted to be given the usual up and down and endwi'se reciprocatory motions common to four-motioned feeds. Up and down motions are transmitted to the forward end of the feed-bar and the feed-dog carried thereby, by a feed-lift eccentric 93 carried by the rotary shaft 5I. The eccentric 93 is surrounded by a strap 94 formed integral with a pin 95 slidingly mounted in a socket 99 formed in the feed-bar.

Oscillatory motions are transmitted to the feedrocker 92, thereby to give to the feed-bar and feed-dog their back and forth motions, from a feed-drive eccentric 91, also secured upon the shaft 5I. 'A block 98 surrounding the eccentric 91 is embraced by the forked end 99a of a lever 99 the hub 99h of which is journaled on a stud |99 secured in the upright wall portion 8 of the machine frame. The other arm 99h of the lever 99 is slotted, as at 99. and lies adjacent an onpositely extending slotted arm I I having a split hub I l! I secured, as by pinch screw |02, upon the hub 92a of the feed-rocker 92. The feed-rocker is ,iournaled on a rod |03 held in bushings I 9d secured in the upright portions 1 and 8 of the machine frame. Oscillatory motion is adapted to be transmitted from the lever 99 to the arm IIII by means of a stud |95 (Fig. 9) having a head |05@ one portion |b located within the slot 99z and another portion projecting through the slotted arm I0| where it carries a slide-block |06 tted within the slot in said arm. .A washer |01 surrounds the stud |05 between the arms 991 and IOI. The stud |95 may be adjusted lengthwise of the arms 99h and IOI thereby to vary'the amplitude of motion transmitted to the latter arm and thence tothe feed-rocker 92, Vfeed-bar 9| and feed-dog 89 from the constant throw of the eccentric 91. A screw-driver actuated nut |08 threaded on the outer end of the stud |05 serves to clamp the stud in its various positions of adjustment. To facilitate shifting of the stud |05 after the nut |08 has been released, a hand-actuated adjusting lever |09 is located in a readily accessible position at the rear side of the machine. This lever is secured upon one end of a rockshaft II9 journaled in the upstanding portion 8 of the machine frame. The other end of the rock-shaft has secured to it an arm III the free and forked end III a of which engages a pin |c projecting from the head IIlliL of the stud |05. The pin |05c is preferably located eccentric to the axis of the stud |95 so as to prevent interference between the forked end of the arm III and the hub 99h of the lever 99 when the stud is shifted to one extreme position. It will be apparent that with the nut |08 released, actuation of the handlever H19 will shift the pivotal connection between the arms 99b and IBI thereby to vary the feed-and-return strokes of the feed-dog.

Cooperating with the above described lower feeding mechanism is an upper four-motioned feeding mechanism including the upper serrated work-feeding foot 64 above mentioned. The foot 54 is secured, by a screw II2, to the lower end of a vertically disposed feed-bar II3 pivotally connected, at its upper end, to one end of a lever I4, of the third order. The opposite end of the lever I I4 is forked and pivotally and slidingly connected at II5 to the machine frame, preferably through the medium of a bracket H6 secured upon the rear side of the head 4. oscillatory movements are transmitted to the feed-bar I I3, thereby to give the feeding foot 64 its feed-andreturn strokes,v by the feed-rocker 92, hereinbefore mentioned. As sho-wn most clearly in Figs. 5 and 9, the split hub IOIa, of the arm IOI, has formed integrally therewith an upstanding arm II'I to the upper end of which is pivotally connected one end of a link IIS. The other end of the link is adjustably connected to the lower end of a rock-arm I I 9, secured, by a split clamping hub |20, to one end of a rock-shaft IZI journaled in the lower Iportion of the bracket-arm head 4. At its other end the rock-shaft has secured to it a rock-arm |22 connected by a link |23 to the upper feed-bar II3. A guard-plate g securedupon the work-plate 9, preventsaccidental contact with the rock-arm II9.

From the foregoing it will be understood that rocking motions of the feed-rocker92 will effect feed-and-return movements of both the vlower feed-dog 89 and the upper feeding foot 04 and that the amplitude of the motion transmitted thereto from the eccentric 91 may be varied by adjusting the position of the stud |05 connecting the lever 99 and the arm I9I. The stroke of the upper feeding foot may be additionally varied' relative to the feed-dog by reason of an adjustable pivotal connection between the link II8 and the rock-arm H9.

As shown most clearly in Figs. 4, 5 and l the lower end of the arm I I9 is formed with an arcuate slot IIQa in which one end of the link II8 is adapted to be adjustably secured by a clamping bolt i |33. With the link IIB pivotally connected in the lower end of the slot I I9, as shown in the drawings, the feed-and-return motions transmitted to the feed-dog 89 and feeding foot 64 are equal. In certain classes of Work it is desirable that the upper plybe fed slightly faster 4. assenso;

thanthe; lower ply.; This may; be; acc.omplished-y by adjustingthefpivot bolt,|;| 8" upwardly; in the. slot H9:a and clamping it in its adjusted;position thereby increasing, the, feed-and-return strokes of the Yupper'feeding foot.

In order that the feeding movementy ofthe foot 64 may effect feeding of the Work it` is essential-that the foot be forced downwardly into pressure contact with the` work. This is effected partially, as hereinafter will be described, by a coil spring I 24 located mainly within a vertically disposed tube |25 having at its upper end a head |25a secured to the bracket-arm head 4 by a screw |25. The lowerr end of the spring protrudes from the tube |25 and bears upon the lever ||4. The tension of the spring may be varied, thereby to cause morel or less pressure to be transmitted to the feeding foot 64, by the adjustment of a screw |21 threaded throughthe head |253" and having its lower end bearing against a plug-head |28 seated upon the upper end of the spring |24. The tension-adjusting screw may be locked in its various positions of adjustment by a clamp nut |29 threaded on the screw |21 and abutting against the head |253.

As is customaryinfeeding mechanisms of'this nature, the lifting presser-foot and the feedingfoot are each alternately depressed'onto the work and lifted therefrom, the lifting presser-foot being raised during the work-feeding stroke of the feeding-foot and bearing on the work toA hold it againstA movement during` the time that the needle is in the'work and theupper and lower feeding elements arebeing retracted after a feeding stroke. This alternate raising and lowering ofV the feet is effected from an eccentric; |30 formed on the mainy shaft |and located-within the cavity c hereinbefore mentioned, in the bracket-arm 3 (see Fig. 5). The eccentricl is surrounded by a block |3| which is embraced by a fork |32 projecting downwardly from a split sleeve |33 clamped upon a hollow rod |34 mounted', forendwise sliding movements, in bushings |35 and |35a securedin the arm 3. A stud |32EL secured in the rear wall of the arm 3 is slidingly fitted within a slotl |32b'formed in one arm of the fork |32' to guide the fork in its lateral movements'and to'prevent it from turning about the axis ofthe rod |34. Upon the rear end of the rod |34 there is clamped the-split-hub |36f-ofa vertically disposed slotted arm |36; Located adjacent the arm |36 isma second-slotted arm |31 the split upper end |318L of'which is clamped upon one end of a rock-shaft |38journaled in abracket |39 secured by screws |39EL to the rear-side of the bracket-arm headv 4. At its opposite end the shaft |38 carries a downwardly extending rockarm |40 to the lower end-of which ispivoted one end of a link |4| connected at its opposite end to part |42 of an angle lever` |42. A second part |421- of that lever is pivotally connectedat y to a clamp-collar |43 secured Aupon the presserbar 19. A third part |42c ofthe lever |42 is pivotally connected at a to the lever I4 hereinbefore mentioned.

A stud |44, adjustably mounted in the slotted arm |361-carries ablock |45 slidingly fitted Within the slot in the arm |31. This stud and block serve as a connectingfmeansbetween the arms |36 and |31 whereby* endwise reciprocation of the rod |34, under the inuence of the eccentric |30, is translatedl by the arms |36.. and |31 into oscillatory motion inthe shaft |38, which through the rock-armv |40 results inendwise reciprocations of the link |4|. Theamount. of oscillatoryl motion .transmittedto theshaft |38, link 4 |i andv lever; |42 and thereby the amount of verticall movementgiven to the feet 63 and 64 may be varied by adjusting the stud |44 and block |45 lengthwise of the arms |36 and |31. A clamp-nut |46 serves to clamp the stud and block in their various positions of adjustment.

From the foregoing it will be understood that rotation of the main shaft 'I5 will, through the elements |30, |3|, |32, |34, |36, |31, |38` and |40, effect enclwise reciprocations of the link |4| and thereby oscillations of the three-armed lever |42 alternately about the fulcrum points y and e as later will be described.

In line with the fulcrum y, the lever |42 carries a roller |41 which tracks the walls of a slot |48 formed in a fork-like member |49 secured, by screws |50, to thehead 4. This fork and roller guide the lever |42 in its vertical movements and prevent -swinging of the collar |43r and the presser-bar 19 about the axis of the latter;

Within the cavity c, the machine frame is formedwith an upstanding wall w (see Fig. 1) which connects the front and rear wallsl of the arm- Bland forms therewith, and with a mainshaft bearing supporting wall w' inthe arm, an auxiliary reservoir R into which lubricantA is splashed from the main reservoir R by the actuating ofthe looper-operating mechanism. Oil in the reservoir R is engaged'by the fork |32 and the block |3| and is splashed thereby into contact with the presser-bar and feed-barlifting mechanism located in the cavity, whereby those parts are kept well lubricated.

As shown most clearly in Fig. 5, the bore in the bushing |35 in which theerod |34 is slidingly mounted, is closedby awelch plug p. The hol'- low rod |34 is formed with radial ports |34a and |34@ which permit the escape of air and thus prevent the rod4 from building up pressure in the bearing bushing |35. The port |34by is aligned with a duct |331.1 inthesleeve |33v thereby permitting any. oilwhich may enter the bore in the rod |34 to gravitate into a cavity |3|a in the block |3| from which it passes through ducts |3|bin said block to-the bearing surfacesof the block andthe eccentric |30.

AsA hereinbefore statedfthis invention has as one-of. its objects to'provide a sewing machine which is capable. of high speed and in whichv the load appliedl tothe drivingV shaft will be relativelyy light and more nearly uniform than in prior machines. This has been accomplished largely by the construction and operation ofthe upper feeding mechanism and the automatic presser-foot lifting mechanism.

It is well known in the sewing machine art that the higher the speed of-themachine the greater must be the springpressure applied to the presser-foot so that it will quickly descend and grip the work after each upward movement thereof by the action of the'under feed-dog. The same is true of upperT feeding mechanisms.

Obviously, the greater thelpressure'- appliedto the presser-foot or` thev upper feeding foot the greater will be the load on the driving mechanism whichis required to-actuate those elements. Furthermore, it will be-apparent that asthisload is applied periodically, that is during the time when the springs are being compressed, the high pressure of the spring Will'not only-apply an undue load on the mechanism-but also anon-uniform one which results in excessive wear in the partsand causes noise and vibration.

The present top-feed and presser-foot lifting mechanisms overcome these' undesirable effects by theembodiment therein of a pair Iof relatively weak springs, each adapted to apply approximately one half of the required pressure, and

. means cooperating therewith whereby the combined pressures of those springs are applied iirst to one foot and then to the other. By reason of this construction the load on the machine is greatly reduced due to the fact that only half of y the total spring pressure is required to be overcome at any one time. In other words, the loads imposed on the machine alternately by the top feed and presser-foot mechanisms are each so divided that one half thereof is applied at each one half rotation of the main shaft instead of each full load being applied once at a given point in a rotation, as in prior constrctions. Thus not only is the maximum load on the machine reduced but it is also applied more uniformly.

The action of the top feed and presser-foot lifting mechanisms will best be understood by reference to diagrammatic Figs. 14 and 15. In the position shown in full lines in Fig. 14, which corresponds to the position shown in Fig. Li, the lifting presser-foot 63 and the feeding foot t4 are in pressure contact with the work under the iniiuence of the springs S2 and |24, respectively, as indicated by the full line arrows. Ignoring the action of the lower feed-dog which in its upward movement eii'ects a slight vertical movement of the upper feeding foot, the actions of the upper feeding foot and the lifting presser-foot are as follows: During the first 90 degrees rotation of the main shaft, after the parts have reached the positions shown in full lines in Fig. 14, the feedrocker is rocked rearwardly and both the lower feed-dog 8S andthe upper feeding foot 64 are given their work advancing movements. During that 90 degree rotation of the main shaft the eccentric |36 shifts the rod Vi 3d rearwardly, which, through the mechanism hereinbefore described turns the rock-shaft |38 and the rock-arm |40, clockwise, as viewed from the head end of the machine, from the position shown in full lines in Fig. 14 to the position indicated in dotted lines. Thus, through the link Iii the lever |112 is turned counterclockwise about its fulcrum z on the lever H4. This causes the fulcrum y of the lever |42 to be raised carrying with it the collar |43, the presser-bar and the presser-foot 63 secured thereto to the position indicated in dotted lines in Fig. 14. It will be apparent that during this movement of the parts the spring 82 will react through the lever |42, yon the lever iii-i whereby the force of that spring is added to the force exerted by the spring |213 to depress the upper feed-bar and depress the feedingfoot 64 into contact with the work with a pressure equal to the combined forces exerted by both springs.

During the next 60 degrees rotation ofthe main shaft the rock-shaft |38 and rock-arm mi) are turned counterclockwise, as viewed in Figs. 4 and 14; whereupon the link ll turns the lever |42 clockwise about its fulcrum e thereby lowering the fulcrum y until the presser-foot 63 again bears on the work under the pressure of the spring 82, the feeding foot 6d, at that time, engaging the work under the pressure of the spring |24 as indicated by the full line arrows inFig, 15. Further rotation of 9U degrees of the main shaft causes continued counterclockwise movement of the rock-shaft |38 and rock-arm itil and brings the parts to the position shown in Fig. 7 and indicated in dotted lines in Fig. 15. Inasmuch as the presser-.foot is, during4 that movement, in

pressure contact with the work and therefore cannot be further depressed, Vendwise movement of the link |4| causes the lever V|42 to'be turned clockwise about the fulcrum y thus lifting the fulcrum e and lever |I4 connected therewith. This results in lifting the feed-bar |3 and the feeding-foot in opposition to the spring |24 whereupon the pressure of that spring reacts through the lever |42 to press downwardly on the fulcrum y and the presser-foot connected therewith. In this position the presser-foot is iield upon the work under the combined pressures of both springs 82 and |24, as indicated vby the arrows at the right in Fig. 15. Another degrees rotation of the main shaft turns the shaft |33 clockwise, the lever |42 counter'clockwise about the fulcrum y, thereby lowering the feeding foot i into contact with the work and restores the parts to the position shown in Fig. 4 and illustrated in full lines in Fig. 14, thus completing the cycle.

From the foregoing it will be seen that during one complete rotation or the main shaft the springs 82 and |24 are alternately compressed and their combined forces are transmitted first to one foot and then to the other.` As hereinbefore stated trie amount of pressure exerted individually by the springs 82 and |211 is capable of being varied by manipulation of the screws 86 and |21, respectively.

Having tliusset forth the nature of the invention what I claim herein is:

i. in a sewing machine having a frame and a work-support; the combination with a four-motioned feeding mechanism located beneath said work-support, of a complemental upper four-motioned feeding mechanism including a work-feeding foot located above said work-support; an operative connection between said feeding mechanisms to give to one feeding mechanism workadvancing movements from the other, a lifting presser-foot; individual springs reacting against said frame for depressing said upper feeding foot and said presser-foot; an angle lever having one part connected with each of said feet; means engaging another-part of said lever to osciliate the lever to cause it alternately to lift and depress said feet and to transfer to the depressed foot the spring pressure normally applied to the other foot. n

2. A sewing machine combining a frame; a work-support; a work-feeding mechanism located above said work-support comprising an upright feed-bar; a feeding foot secured to the lower end of said feed-bar; a vertically movable presser-bar; a lifting presser-foot carried by the presser-bar; a rst compression spring normally acting on said feed-bar and reacting onV said frame to depress said feeding foot; a second compression spring normally acting on said presserbar and reacting on said frame to depress the presser-foot; an angle lever having one part pivotally connected with said presser-bar and another part pivotally connected with said feed-bar; and means acting on a third part of said lever to rock it alternately in opposite directions about its pivots to cause it alternately to depress said feet into contact with work located on said worksupport and alternately to lift said feet in opposition to the spring pressure thereon, said lever in its rocking movements serving to transfer to the depressed foot the spring pressure normally acting on the other foot.

3. A sewing machine as set forth in claim 2 in which the springs which depress the feeding foot "and the presser-footiare coil'springsmounted'for en'dwise` compression i in tubular-supports carried by the machine frame, and in "which vindividual 'meansiislprovidedifor varying the pressureproduced by' eachspring.

4. Afsewingmachine asset Aforth in claim 2 in whiclrmeans is providedfor varying the amount of'rocking'motion transmittedto theangle lever, Athereby to vary'the height `of'lift of theV presser- 4footandfeeding foot.

5. A sewin-gmachine 'combining a frame; a

work-support; a work-feeding mechanism 1o- 'cated above "said 'work-support and comprising an upri'ghtfeed-bar'anda feeding-foot secured part pivotally connected with said feed-bar; means acting'on vanotherpartof said ylever to rock it alternatelyin opposite directions Vabout its pivctsto cause italternately to depress said feet Jinto Acontact with work located onsaid work-'sup- '2- port and alternately to'lift said'feet in opposition `to said spring means; a stud carried by and'projecting laterally -from-said'collar; and a rigid member secured 'to said frame vand affording spaced and opposed vertically arranged bearing surfaces which engage -thel opposite sides of said stud to prevent oscillation Lof the 'presser-bar about its longitudinal axis-under the' influence of said presser-foot lifting means.

`6.A sewingmachine vcombining a frame; a work-support; Ya work-feeding mechanism -located above said work-support comprising an upright feedbar,afeeding foot secured to the lower end of-said feed-bar, a lever having one end-fulcrumed on saidframe-and-aifording-at its other end'a pivotal support `for vsaid feed-bar; a -vertically movable presser-bar; a I lifting presser-foot carried l`by the presserAbar; a first compression spring normally actingonsaid feed-bar andreacting on-saidframe to-depress said-feeding foot; asecond compression spring normally acting on said presser-barand .reacting on said frame to depress the presser-bar; an Vangle lever having one part vpivotally connected .to the first mentioned lever and another part pivotally connected with said presserbarandmeans acting on a: third part of said .lever to rockY it alternately inopposite directions aboutlitspivots to cause it alternately to .depress said lfeet into contact with work located on said work-support--and alternately V'to lift said feet in opposition tothe 4spring-pressure thereon, saidV angle lever inits rockingmovements serving Ato transfertothedepressed foot the spring pressure normally actingontheother foot.

7. A sewing machine as :setforthin claim 6 in which the rst mentioned leverfhase'a-oating fulcrurn on the machine frame; in which `the compression spring which depresses the-feed-bar acts on the rstmentioned Vleverand thereby transmitted to the feed-bar; and -in -whichmeans engages the feed-,bar below its pivotal connection with the rst mentioned lever to givetofthe feedbar feed and return movementsin timed relation with its vertical movements.

8. A sewing machineras setforth inrclai-m 6 in which the first mentioned lever has a .sliding pivotal connection with aloracket secured to the machine frame, and lin `which-the '-'spring -which depresses theV feedebar bears uponthatleverniermediteiis-Ysiidmg Apivot 'and "the lpivotai liconlnection between the lever La'n'd the feed-bar.

9. In a sewing machine having af'base,.a standcluding an upright feed-bar ysupported'fro'm'e'said vhead and a Work-'feeding foot on -thelower'end of said feed-bar; -means v actuated fby' the @second shaft for giving toi-said 'feed-bar feed-f and `rreturn movements; and means vfor giving lto -said feed-bar up and down movements in timed irelation Awith its feed vand 'return movementsfcomprising aneccentric `on=-said r'st shaft, a-SIi'debar mountedin said f'bracket-larm a forklsecured Ato said slide-bar-and embracing said eccentric, 'a 'rock-shaftsupported by said head, an operative-connection betweenasid slide-bar and :said

Arock-shaft to give to the latter oscillatory -motions from the sliding movements of the former,

--and means actuated by said rock-shaft to lift'an'd Vdepress said feed-bar.

10. In a sewing machine as set forth in claim l9, alubricant reservoir formed in said bracket- 'arm and holding lubricant which is engaged by vsaid fork and its actuating means, whereby said eccentric, fork and yslide-bar 'are splash-lubricated.

1l. In a sewing machine having an upper four-motioned feeding mechanism as set forth in claim 9, in which the operative connection between the slide-bar and the rock-shaft includes adjustable means for varying the rocking motion transrriitted to the rock-shaft from the constant throwV of the eccentric, thereby to vary the vvertical movement of the feed-bar.

12. In-a sewing machine having an upper fourmotioned feeding vmechanism asset forth in claim 9, in which the operative connection between theslide-bar and the rock-shaft comprises an arm on said slide-bar, an arm on saidrockshaft, said arms being arranged side-by-side,

and an adjustable'connection between said arms -for transmitting oscillatory motions to the latter from reciprocatory motions of the former 'and '-for lvarying the Vamount of oscillatory motion transmitted to the rock-am.

-13. A sewing machine combining a frame in- -cluding a base, a standard, a bracketarmanda head; a work-support; a first shaft journaled in said bracket-arm; a second shaft journaled in `said base; an upper work-feeding mechanism operating above saidwork-support and includingl a `substantially horizontal lever fulcrumed at one end on said head, a vertically andhorizontally movable upright feed-bar pivoted at its upper end to the other end of said lever and a feeding foot carried by said feed-bar; means'actuated byfsaid secondshaft for giving to saidlfeed-bar its horizontal movements; and means to give 'vertical movements tothe feed-bar in timed relation vwith its horizontal movements Acomprising anA eccentric on said rst shaft, a slide-bar mounted in said bracket-arm, a connection between said eccentric and said slide-bar for reciprocating the latter vand an operative connection between said slide-barand said lever for oscillating the lever about its fulcrum thereby to raise 'and lower Said feed-bar.

14. A sewing machineas -set forth in claim 13 in which lthere-is a vertically movable presserbar mounted in said head Yand in which the operative-connection between the rock-shaft and the le'ver`-whic`:lrj supports V'the feed-'bar includsa rock-arm on said rock-shaft, an angle lever having one part pivotally connected with said lever and another part pivotally connected with said presser-bar, and a link connection between said rock-arm and a third part yof said angle lever whereby oscillation of said rock-shaft eiects alternate lifting and lowering of said feed-bar and presser-bar.

15. In a sewing machine having a frame afiording a closed compartment and a rotary shaft in Said compartment; a four-motioned feeding mechanism located Within said compartment and comprising a feed-rocker, a feed-bar connected to said feed-rocker, a feed-dog carried by said feedbar, means actuated by said shaft to give to said feed-bar rising and falling movements; means for vibrating said feed-rocker to give to the feedbar feed and return movements comprising an eccentric on said shaft, a two-armed lever fulcrumed on said frame and having a rst arm engaging -said eccentric and a second arm projecting toward said feed-rocker, a rocker arm projecting from said feed-rocker and lying beside and adjacent the second arm of said lever, an

adjustable coupling element between said rockerarm and the second arm of saidlever to transmit motion from said lever to said rocker-arm and thereby to said feed-rocker; and manually actuable means including a member located outside said compartment and a connection from said member to said coupling element for shifting said element to vary the amount of motion transmitted from said lever to said feed-rocker. 16, A feeding mechanism for sewing machines as set forth in claim 15 in which the means for shifting the coupling element comprises a rockshaft journaled in and extending through a Wall of the compartment, an arm secured to the inner end of said rock-shaft and'engaging said coupling element, and a manually actuable lever secured to the outer end of said rock-shaft.

ANDREW B. CLAYTON.

cERTFIcATE oF CORRECTION'. Patent No. 2,559,240. January 18, 19h14.

ANDREW B. CLAYTON.

It is hereby certified thaterror appears in the printed specification of the aboveA numbered patent requiring correction as follows: Page 5, first column, line 1T, for constrctionsfread---construccions-; page 6, first. column, line 65, claim?, after "1e-ver and" insert -is; and second co1- umn, line 19, claim 9,'for asid read --said; and that the said Letters Patent should be-read with this correction therein that the same may, conform to thel record of the case in the Patent Office. r

signed and sealed this luth day of March, A. D. 191m.

' Leslie Frazer (Seal) Acting; Commissioner .of Patents.

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