US1234252A - Buttonhole-sewing machine. - Google Patents

Description

E. B. ALLEN..

BUTTONHOLE SEWING MACHINE.

lpggngggfign APPUCATION FILED JULY a, 1915. Patented July 24,1917.

2 SHEET'SSHEET I.

E. B. ALLEN.

BUTTONHOLE SEWVNG MACHINE,

APPUCATION fILED JULY B, 19M.

Patented July 24, 1917.

2 SHEETSSHEET 2" A TT OR/VEV INVENTOR "cairn sra rs rann r anion EDWARD B. ALLEN, OF BRIDGEPORT, CONNECTICUT, ASSIGNOR TO THE SINGER MANU- FACTURING COMPANY, A CORPORATION OF NEW JERSEY.

BUTTONHOLE-SEVJING MACHINE.

Application fi1ed. July 3, 1915.

7b 112% whom it may concern:

die it known that I, Eowann B. ALLEN, a citizen of the United States, residing at Bridgeport, in the county of lfairiield and Fitatc of Connecticut, have invented certain new and useful Improvements in Buttonhole-Sewing Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention has for its primary object to provide a sewing machine with a patternca-m wheel having actuating means which shall be (puck-acting, intermittent, noiseless, without impact of its operative parts, ac curate, and under positive control under all conditions. It has for another of its objects to combine in a buttonhole stitching machine stitch forming and feeding mechanisms which shall be so positively related in their timing throughout a buttonhole producing cycle that a series of barring stitches of predetermined number and arrangement may be produced at an end of the buttonhole in absolutelyfixed relation with the adjacent side-stitch or stitches, there being no incomplete or mongrel stitches connecting the sidestitches with the stitches composing the body of the bar.

While the present improvement, in its es scntial features, is adapted for widely different types and varieties of sewing machines comprising pattern-cam wheels, it is designed more particularly for embodiment in buttonluile stitching machines of the type represented in my United States Patents No. 1,030,040, of June 18, 1912 and No. 1,039,945, of September 24, 1912, employing rotary stitch-forming mechanism comprising a laterally jogging needle performing two reeiprocations for Bach rotation of the main-shaft and cooperating in the production of stitches with. oppositely reciprocating loopers mounted upon and movable with a carrier performing rocking movements of onehalf the frequency of the needle reciprocations.

According to the present improvement, in its preferred form, the turning movements of the stitch-forming mechanism and the feeding movements of the worleholder rela tively to the latter are derived from a feed wheel having peripheral gear-teeth meshing with a pinion which rotates with a periph' orally toothed gear-wheel constituting the driven member of the feed\vheel actuating Specification of Letters Patent.

Patented July 241, 1017.

Serial No. 37,83

means meshing with a driving member in the form of a disk having a plurality of eccentrically disposed pins movable upon an axis within the periphery of the driven member. The peripheral teeth of the driven member are shaped to afford respectively active and dwell-producing portions in their inner and outer parts for positive engagement with the rotary pins or elements of the driving member for production of a plurality of forward impulses of the driven member for each rotation of the driving member with intermediate dwells of fixed duration extending through a substantial portion of the rotation of the driving member which later is connected with and rotates in unison with the main or driving shaft.

By the means described, the feed-wheel is caused. to perform a complete rotation of uniform step-by-step operative movements foreaeh buttonhole producing cycle, while the operative positions of its cam portions at corresponding stages of successive buttonhole producing cycles is absolutely fixed so as to time the relative movements of the work with the working position of the stitchforming mechanism with precision in rela tion to the jogging movements of the needle.

In the mechanism disclosed in my said patents, the feed-wheel was actuated by a clutch device which was lacking in precision in a degree which was inappreciable in the spacing of the stitches along the sides and around the eyelet-end of the buttonhole, but which was liable to produce a more or less defective bar at the narrow end of the but tonhole by reason of variation in the timing of the needle-jogging movements with the lateral throw of the work-holder in passing from side-stitching to barring conditions. It is one of the objects of the present im provement to remedy this defect and to insure absolute precision of timing of the feeding and needle-jogging devices at this critical point; and this is effected by positively timed actuating means for such devices each deriving its operative movements from the main-shaft.

In the accompanying drawings, Figure 1 is a rear side elevation of a buttonhole sewing machine embodying the present improvements, Fig. 2 a plan of certain portions thereof including the feeding mechanism and its actuating means, and F 3 a a represented in elevation.

chine-frame with the, feeding mechanism Fig. i is a front end elevation of the needle-actuating means, and Fig. a similar elevation, upon a larger scale, of the looper mechanism. Fig. 6 is a bottom view of the feedwheel. Fig. 7 is an enlarged plan view of the feed-wheel actuating device. Fig. 8 is a diagrammatic view representing the method of forming thebar at the completion of the side-stitching, and Fig. 9 a diagrammatic view showing the finished end portion of the buttonhole.

The machine is shown constructed with a frame comprising the hollow rectangular base 1 from which rises the hollow standard 2 from the upper portion of which extends the tubular arm 8 terminating in the hollow head 4. Journaled within the base is the main-shaft 5 formed with the cranks 6 connected by the pitmen 7' with similar cranks 8 of the upper shaft 9 journaled in the tubular arm 3.

Fixed upon the main-shaft is the hub 10 of the bevel-pinion 11 meshing with a simi-' lar pinion 12 upon the short shaft 18 journaled in a suitable bearing of the cross brace-member 14 of the base 1 and carrying upon its upper end the disk 15. The disk 15 carries two diametrically opposite and eccentrically disposed stud-pins 16 secured within suitable apertures of the disk by means of cross-pins 17.

Journaled within a suitable bearing of the brace-member 1d and in a bracket-member 18 depending from the top of the base 1 is a shaft 19 having fixed thereon the hub 20 of the driven wheel or member 21 which is formed with the peripheral gear-teeth 22 constituting driven elements adapted for engagement with the driving pins or elements l6. 2

As represented particularly in Fig. 7, each of the gear-teeth 22 has a straight inner or active portion Z) arranged in tangential relation with a circular outer portion a and inclined at an angle with a radial line passing through said tooth; and the adjacent edge of the neXt tooth has a straight inner portion parallel therewith and joinedwithits circular outer portion by an intermediate curved portion a concentric with the outer portion of the first-mentioned tooth. The spacing apart of the concentric or dwell-producing portions and straighter active portions of the adjacent teeth corresponds with the diameter of the driving stud-pins 16.

As illustrated in Fig. 7 ,c the driving mem ber 15 is designed to turn in clockwise direction, the stud-pin or driving element 16 at the left being active in imparting a driving impulse to the driven member 21. As this stud-pin enters the outer concentric or dwellproducing portion of the cam-recess between the teeth 22, the other driving element is just emerging from the adjacent cam-recess,

but still maintains contact relation with the outer part of the intermediate tooth.

In the continued movement of the member 15, the left-hand studpin continues its advance within the cam-recess or interdental space until it reaches the straight or active portion of such recess, as represented in Fig. 7, at which instant the other stud-pin reaches the flattened peripheral portion cl of the intermediate tooth which is cut away for clearanceso as to avoid conflict in the advance of the until now stationary driven left-hand stud-pin in itscircular path, it en-- counters the straight inclined active portion 6 of the tooth which it engages and impels it in the same direction in its inward movement along such straight edge and then outward to the point of tangency of the straight portion with the outer circular portion a at which point in the rotation of the driving member the other stud-pin enters the adjacent cam-recess.

As the second of these stud-pins moves along the concentric portion of its respective cam-recess, the first remains in contact with the intermediate tooth 22 which is held locked against circular movement between the two stud-pins'for a substantial portion of a rotation of the driving member 15, and until the second of the stud-pins reaches the straight inclined or active part of the camrecess at which point the first of the studpins recedes from its respective tooth, as previously described.

. The operation above described is repeated for each semi-rotation of the driving mem ber corresponding with each lateral movement of the needle, whereby the driven member is caused to perform two advance movements with intermediate positively timed dwells for every rotation of the driving member. As will be observed, the rela tive duration of movement and dwell of the driven member in each engagement of its teeth by the Cll'lvlllg elements 16 is determined by the length of the circular arc of the outer portion of the tooth which is adapted to assume concentric relation with the shaft 13 for the dwell-producing period above described, it is found in practice that member. In the further movement of the ice 2 it may be operated effectively when the driving member is turned in the reverse direction; The transmission of intermittent movement from the driving to the driven member is in any case effected entirely without shock or harsh engagement of the interengaging parts, and the mechanism may thus be driven at high speed without noise or excessive wear- As represented in the drawings, the shaft 19, "has, fixed. thereoniabove i theadriven mem-. ber thehub F28 ofra pinion 2& meshing (with the peripheral; gear-teeth :25 formed upon the, rim 10f.thQ,TBBCl7\VhGl 26 which is. suitably journaled within the machine base 1. The feed-wheel (is i shownoformed in its up-i per rtlracetwith :the feed cam-groove 27 and the tside=shift: icam groore 28 and upon, its lower face with they stitching mechanism turning camsgroove 29:: The ,1 feed-camgroove 27 is entered by a a stud 30 depending from .a lever, 31,1l1aving its hub 32 fulcrumed up on .the it stud-screw 33a depen ding from the bed 1 The lever 31:is:formed with-a groove in which is adjustably secured theupwardly extending studrpin 34f. proj ecting through an opening 11inithe base.-

The sidevshifticamrygroove 28vis entered by a stud 35 upon one arm. ofa rock-leven36 fulcrumedi.intermediate; its: ends; at 37 1 and carrying:atitszopposite end a stud 38which ispivotally; and slidingly connected, in-a manner ,well: known. with the! work-holder cross.slide platep39; 2 TheHslide-plate 39sis movably sustained vupon. transverse guideways .of the main slide-plate 10 which :is formedhat its rearward end with the ,transverseslot d1; enteredbythe studq et from which itderives longitudinal feeding move-i ments;

The cross" slide plate carries theuusual cl amp plates 42 affording, the lower. worksupporting members- 1 of ithe', work-holder upon whicln the woi'lpis clampedby the feet 131; of theclamp-arms 414C sustained by thebracketsdo which are secured uponthe clamp-platesA2 all as represented more fully in my pending; application Serial No. 698,778, filedrFebruary .29, 1912;

Asv set forth 'moretfully invmy applicationSerial Now865fi-fl6; filed October 7, 191%, the needle-bar 46 is ,journaledtin the fixed bushing 17: in theiupper member of the bracket-arm head a and is slidingly fitted within and splined to the rotary bushing et which is journaled in thelower member of the bracket-arm head The needlebar is provideduponits lower end with a yoke d9 having a cross-pin 50 upon which is .slidingly'mountedtheslide-block 51 carrying the eye-pointedlaterally jogging nee- The needle-bar has fixed thereon a collar 58 carrying the lateral studbi c which is embraced by one end of the pitman 55 whose opposite end embraces, the crank-pin 56 upon the crank-disk 57 carried by the ac tuating shaft 58; The shaft5S is driven by the shaft 9 through a trammel connection comprising the disks 59 and 60 mounted upon the respective shafts' and provided with theusual pin and cross-groove connection,through which the shaft 58 derives two rotations for each rotation of the shaft 9.

The needle-carrying block 51 is provided with a lateral. stud-pin 61. adapted when in its lower position tomove in one of two parallel ways of the guide-arm 62 secured upon and depending TIOJILztllG block 63 sustained by the,,rotary bushing 18, and when in. itsi'upper position to beengaged by the forkedvdepending'aarm 6st of an elbowdever fulcrumedi by means of the ,stud-screwtfio upon the ,block:63.;and provided with a lateral arm 66 carrying the stud 67.

The stud, 67 enters, a circular guiding groove .68 inthe ring 69xhaving its: hub 70 secureduponrthe reciprocating rod]? 1 which is ijournale'd vin ,thet-bracketarm head a d. Theguidewing 69 is sustained concentrically with the needle bar A6. Thea-rod 71 entries a cross-bar. 72 adjustably connected bygmeansof thepitman 73 with the lateral crank-arm 7st securedupon the roclvshaft 3 andisprovided with a forked lateral arm 7 6, {which a embraces a triangular actuating cam .77" upon the shaft 9.' Through the mechanism just described the needlecarrying block'receives lateral joggpjngmovements upon its. supporting, pin 60 ofonehalf the frequency ofthe needlebar reciprocations.

As represented more; fully in my said PatentiNo. 1,030,046,11pon a suitablermenr; ber 78 of thebase 1 is journaled the rotary looper-support 79' having the depending bushing 80 iandicarryingrthe fulcrum-pin 81 upon whichmis mounted the rocking loo ')er,-carrier 82 sustaining theeyed looper 83 andthe forked looperSi and its overlyingspreader 85. The looper-support also sustains the .loop-detainer. S6 cooperating with theieyed looper 83 in thehandling of the lower threads The loopers, spreader and loopsdetainer derive their operative movements from themaiushaft 5 through operative connections including thetelescopically arranged tubular rods87 and 88 passing through the bushing; .80.

The cam-groove 29 isentered by a rollerstud 89 projecting fronrthe bar- 90 which is secured upon the slide-rod 91 mounted in bearings within the machine-base and con-- nected by the upright bar 92, the forked plate 93 and notched collar 9 1 with the upper slide-rod 95 sustained in suitable bearings of the bracket-arm.

The bar 91 carries at its forward end the rack 96 meshing with the pinion 97 fixed upon the looper-support bushing 80, and the rod 95 is connected at its forward end with therack-bar 98 slidingly journaledwithin a suitable bearing of the bracket-arm head and havingrack-teeth meshing with the pinion v99 fixed upon the rotary needle-bar bushing 18. The movement of the slideframe, comprising the rods 91 and 95 and the connecting members 92, 93 and 9 1, under the influence of the cam-groove 29, thus causes the rotation of the cooperating upper and lower stitch-forming elements in a manner well known. j

The machine comprises as usual clampopening and closing devices and spreading "means, a slit-cutting dev1ce with actuating means therefor, and a stop-motion for. controlling the period of action of the stitchforming and feeding mechanisms, but these are not specifically described herein as they form no part of the present invention end of the slit and the succeeding thrusts throughout the edge-stitching operation being alternately in the work and in the sill:

to form the side stitches 8. During the stitching the work-holder receives first a step-by-step rectilinear movement up to the narrow part of the eye portion from which point it continues lengthwise of'the slit and receives also a slight sidewise step-by-step movement as far as the center of the eye portion at which point thelengthwisefeed ceases and the stitclrforming mechanism performs a semi-rotation for spacing the stitches around the semi-circular portion of the eye. At the completion of such portion of the eye, the lengthwise feed is resumed in conjunction with a reverse sidewise movement along the contracted portion of the eye,

at the. end of which the rectilinear lengthwise feed is performed in completing a second side stitching operation. I

As the needle rises after performing its final depth thrust in the material at the end of the second side stitching operation, it

performs its usual lateral movement while the clamp simultaneously receives through the influence of the side-shift feed-cam groove an equal lateral movement in the opposite direction while the final full length wise feed-step is given to the work-holder, thereby positioning the needle in an initial depth-stitch thrust for production of the initial barring stitch 25 extending from the outer line of needle-punctures on the second side of the buttonhole to that of the opposite side ofthe latter.

WVhile the reciprocating and lateral jog ging movements of the needle continue, the stitching mechanism performsa reverse stepby-step semi-rotation and the work-holder similarly performs a reverse step-by-step lateral movement in such manner as to place each second needle-thrust within the slit progressively at different points and the intermediate thrusts within the work in a line and final jogging movements.

line crosswise of crosswise of the slit to form the intermediate barring stitches t, the thrust succeeding the depth-stitch puncture opposite the initial depth-stitch puncture of the bar being within the end of the slit, after which a succeeding depth-stitch puncture is made coincident with the final side-stitch depth puncture which is succeeded by a puncture within the slit followed by a second puncture with i in the slit produced by a full step jog of the work-holder opposite to the final needle-jog, and in the same direction as the preliminary side-shift movement at the beginning of the barring operation, the progressive step-by-step lateral movement of the workholder having continued for a distance equivalent to the distance apart of the outer lines of punctures of the side stitches at the smaller end of the Slit;

The work-holder occupies initially a central position in which the work receives the slit and both lines of side stitches between the eye and the end of the slit, andin the barring operation itthus derives from the feed-wheel'initial and final lateral jogging movements in the same direction inopposition to simultaneous lateral movements of the needle with an intermediate series of step-by-step movements in the opposite di-' rection aggregating in length said initial By this means the work-holder is moved from initial position toward the outer line of needlepunctu'res of the first line of side stitches,

thenoppositely to a point beyond and at the same distance from initial position, after which it is returned to initial position at the conclusion of the barring operation.

The depthestitch punctures in the production of the bar may be made in a straight the direction of length wise feed sufficiently beyond the small end of the slit to prevent liability of pulling out of the central barring stitches laid substantially lengthwise ofthe slit, but they are preferably made in EtC-OHVQXLV curved line, as represented in Figs. 8 and 9, so as to make" the line of needle-punctures slightly curved but with the stitches drawn up in a substantially straight outer line when set, owing to the slight yielding of the fabric. This may be accomplished by producing a slight progressive to-and-fro step-by-step longitudinal feed during the laying of the barring stitches.

When the working position of the needle upon the needle-bar is such that both the edge-stitch and depth-stitch thrusts are performed sutliciently eceentrically to the axis of rotation of the needle, the workholder may remain stationary during the stitchin of the semi-circular portion of the eye OI working position of the needle should not be sulliciently great to produce the required curvature of the eye-stitching, these stitches may be laid farther from the axis of rota tion by slight longitudinal and; lateral movements of the Work-holder in such part of the stitching operation. the feed-cam grooves being shaped accordingly in the present machine, as represented in the drawings.

In the control of the longitudinal and lateralpositions of the work-holder and the circular positions. of the stitching mechanism for the several stages of the stitching operation, the effective portions of. the respective CfilllI-gil-OOWBS are rep-resented in 2 and (3- by the reference characters 2'79, 28 and 29 for the first side stitching period; by the characters 27 28 and 29,. for theeyestitching period by the characters 27 28 and 25) for the second. side stitching period and by the characters 2 barring period. As will be observed, the feed-cam groove 27 and the side-shift cam.- groove 28 have their principal active por tions at 27, 27 28 and 28 respectively, while the usually concentric portions 27." and 28, respectively, are symmetrically bowed slightly to produce slightlatera l movements. of the work-holder to supplement the relative lateral movement of the. working position of the needle at the semi-circular portion of the eye, as before described;- The parts 27' and 28 of the feed-andside-shift cam-grooves are made jagged! so asto, pro duce jogging, movements of the Work-clamp in different directions to supplement the needle-jogging movements as described in the laying of the barring stitches succeeding the first radially of the smaller end of the slit.

It will be seen that the actuating mechanism of the controlling cam-Wheel. 26 for determining. the operative movements of the work-holder and the turning movements of the stitching mechanism pl. ys an important part in the precision of operation ofthe machine and the quality of the stitching, especially at. the barred end of the buttonhole, as it is of importance that the initial. barring stitch. shall be: laid With precision at the completionof the second side-stitching oporation, and. that the initial side-stitch puncture shallfihe invariably in the: slit at the beginning of the first side=stitching period...

As shown and described herein, the connection between the driven Wheel 21 the fcedovheel: actuating mechanism and the feed-Wheel such as to. produce only a sinle speed of movement of the feed-wheel relatively to the stitch-forming mechanism for production of afiXednumberof stitches for each buttonhole; but it 1s obvious that change gears may be readily mterposediba ,28? and 29" for the tween the pinion 24: and the peripheral gearteeth 25 of the feed-w11eel so as to. provide for variation in the speed of rotation of the feed\vheel.

In the machine as thus described, the feeding movements communicated to the workholde-r comprise longitudinal step-bystep movements for spacing the side sitches and transverse step-by-step movements which contribute to the positioning of the eye stitches and the barring stitches. These different successions of step-by-step movements continue throughout a stitch-forming cycle, and begin. and end in an initial position of the Work-holder, and they are individually of such lengths and so timed relatively to the operative movements of the needle that every needle puncture of theentire butter-i hole is located with great precision, whereby the buttonholcs of a series are made with. perfect uniformity and in perfect symmetry.

The feeding mechanism of the present improvement is designed more particularly for employment in connection with an endivise reciprocating and laterally jogging needle yvith cooperating loop-taking means, but it 1sv evident that in certain aspects of the. invention it is applicable: to machines employing other types of over-seaming stitch-form: ing mechanism. With any type of overseaming mechanism the stitch, forming mechanism. is preferably given a step bystep semi-rotation in one direction in the stitching. of the semi-circular portion of the eye and a step-by-step semi-rotation in the opposite direction in the stitching. of the bar, the successions of longitudinal step-bystep feeding movements being performed. intermediate the semi-rotations of the stitchforming mechanism.

As thus described, the machine is adapted to performv the stitching. operation after the cutting of the slit, and to produce the barring stitches subsequently to the second. sidestitching period, but it is evident thatv the order of the slit-cutting. action and the, barring may be modified to suit the requirements of the class of Work for which the machine is designed Within the scope of the: present invention. It is also evident that the feecl-ivheel actuating mechanism herein shown and described, as also the character of the cam-grooves. of the feed-Wheel, may be considerably varied Without departure from the invention.

Having thus set forth the nature of the invention, what I claim herein is':

1. In a buttonhole sewing machine, the combination with. stitch-forming mechanism, of feeding mechanism including a rotary shaft, a work-holder, and means connected With said shaft for producing between the stitch-forming mechanism and the "Work-holder in each rotation of said shaft jogging needle and cooperating loop-taking (means, a work-holder, a feed-wheel, connections between the feed-wheel and the work-holder for imparting to the latter a succession of longitudinal feeding movements followed by to-and-fro lateral movements, and actuating means for imparting to the feed-wheel step-by-step rotary movements of a frequency and amplitude in fixed relation with the jogging movements of the needle.

3. In a buttonhole sewing machine, the combination with stitcl1forming mechanism including a reciprocating and laterally jogging needle, a work-holder, a feed-wheel, connections between the feed-wheel and the work-holder for imparting to the latter a succession of longitudinal feeding movements for the side-stitching operation fol-- lowed by a succession of lateral movements in the barring operation, connections between the feed-wheel and the stitch-forming mechanism for imparting to the latter progressive rotary movements intermediate the initial and final lateral movements of the worlrholder, and actuating means for imparting to the feed-wheel step-by-step rotary movements of a frequency and amphtude in fixed relation with the jogging movements of the needle, whereby the initial and final lateral movements of the work-holder are effected in opposition to simultaneously timed lateral jogging movements of the needle.

4. In a buttonhole sewing machine, the combination with stitch-forming mechanism including a reciprocating and laterally jogging needle, a work-holder, a feed-wheel, connections between the feed-wheel and the work-holder for imparting to the latter a succession of longitudinal feeding movements for the side-stitching operation followed by a succession of lateral movements of variable length during the barring operation, connections between the feed-wheel and the stitch-forming mechanism for imparting to the latter progressive rotary movements intermediate the initial and final lateral movements of the work-holder, and

3 actuating means for imparting to the feed-' wheel step-by-Step rotary movements of a frequency and amplitude in fixed relation with the jogging movements of the needle,

whereby theinitial and final lateral move-' ments of the work-holder are effected in opposition to simultaneously timed lateral jog ging movements of the needle.

5. In a buttonhole sewing machine, the combination with stitch-forming mechanism including a reciprocating and laterally jogging needle, a work-holder, a feed-wheel, connections between the feed-wheel and the work-holder for imparting to the latter a succession of longitudinal feeding movetween the feedwheel-and the stitch-forming mechanism for imparting to the latter progressive rotary movements during said period of reduced feeding movement of the work-holder, and actuatlng means for imparting to the feed-wheel step-bystep ro tary movements of a frequency and ampli tude in fixed relation with the jogging move ments of the needle, whereby the initial. and

final lateral movements of the work-holder are effected in opposition to simultaneously timed lateral jogging movements of the needle.

6. in a buttonhole sewing machine, in combination, stitch-forming mechanism including a reciprocating and laterally jogging needle, a work-holder, means for imparting to the work-holder longitudinal feeding movements for spacing the sidestitches, means acting at the completion of the side-stitching period for imparting to the work-holder in the production of barring stitches initial and final lateral jogging movements in the same direction in opposition to simultaneous jogging movements of the needle and intermediate step by step lateral movements in the opposite direction, and means for imparting to the stitch-forming mechanism step-by-step turning movements intermediate said initial. and final lateral movements of the worlnliolder.

7. In a sewing machine, in combination,

stitch-forming mechanism, a work-holder, and means for producing relative feeding movements between the stitch forming mechanism and the work-holder and com prising an actuating member having a circular series of teeth, and a driving member therefor provided with a plurality of successively acting combined driving and holding elements each adapted to positively engage one of said teeth and acting through it to hold the actuating member against rotation until the succeeding driving element assumes active relation with its respective tooth.

8. In a sewing machine, in combination, stitch-forming mechanism, a worlnholder, and means for producing relative feeding movements between the stitch forming mechanism and the work-holder and com prising an actuating member having a circular'series of teeth, and a driving member therefor provided with a plurality of driving elements acting successively upon said teeth each to produce driving impulses and intermediate holding actions extending each through a substantial portion of a rotation of the driving member.

9. In a sewing machine, in combination, stitch-forming mechanism, a work-holder, and means for producing relative feeding movements between the stitchforming mechanism and the work-holder and com prising an actuating member having a circular series of teeth, and a driving member therefor PlOViQlGLl. with a plurality of successively acting driving elements arranged and. operated to impart solely by their engagement with said teeth alternate driving inuaulses and positively controlled dwells.

10. in a sewing machine, in combination, stitch-forming mechanism, a work-holder, and means for producing relative feeding movements between the stitch-forming mechanism and the work-holder and comprising an actuating member having a circular series of teeth, and a rotary driving member therefor having its axis of rotation within the range of movement of said teeth and provided. with a plurality of eccentrically disposed driving elements meshing with said teeth.

11. In a sewing machine, in combination, stitch-forming mechanism, a worleholder, and means for producing relative feeding movements between the stitch-forming mechanism and the work-holder and comprising a feecl-wheel, a rotary driving member provided with a plurality of driving elements and a driven member operatively connected with said feed-wheel and having a. circular series of driven elements adapted, for engagement with said driving ele ments and formed each with dwell-pro ducing and active portion constantly in positive engagement with at least one of said driving elements, whereby the driven member is alternately actuated and locked against rotary movement solely by said driving elements.

[2. In a sewing machine, in combination, stitch-forming mechanism, a work-holder, and means for producing relative feeding movements between the stitch forming mechanisn'i and the workholder and comprising a feed-wheel, a. rotary driving member provided with a plurality of driving elements and a driven member operatively connected with said feed-wheel and having a circular series of teeth each adapted for engagement by said driving elements and formed with diametrically opposite concentric portions adapted to assume concentric relation with the axis of movement of said driving member and for simultaneous engagement by said driving elements.

7 In a buttonhole sewing machine, in

combination, overseaming stitch-forming mechanism including cooperative stitchforming elements, means for in'iparting thereto stepby-step semi-rotations in opposite directions, a main driving shaft for the stitch-forming mechanism, a work-holder, and a continuously controlling connection from. said main-shaft to said work-holder for producing between the stitch-forming mechanism and the worcholder intermediate consecutive semi-rotations of the stitch-forming mechanism successions of feeding movements of fixed length and duration relative to the operative movements of the stitcl1for1ning elements.

14. In a buttonhole sewing machine, in combination, overseaming stitch-forming mechanism including a reciprocating needle, means for imparting thereto step-by-step semi-rotations in opposite directions, a main driving shaft operatively connecting the stitch-forming mechanism, a worlcholder and a continuously controlling connection from said main-shaft to said work-holder for producing between the stitch-forming mechanism and the work-holder intermediate consecutive semi-rotations of the stitchforming mechanism successions of stitchspacing movements of fixed length and duration relatively to the needle reciproeations with intermediate dwells of fixed duration while the needle is in the work.

15. In a buttonhole sewing machine, in combination, overseaming stitch-forming mechanism including a reciprocating and laterally jogging needle, means for c0ntrolling the period of operation of the stitchforming mechanism, means for imparting to the stitch-forming mechanism step-by-step semi-rotations in opposite directions, a workholder, and means for imparting to the worlcholder intermediate consecutive semirotations of the stitch-forming mechanism successions of stitch-spacing movements in fixed length and duration relatively to the needle-jogging movements, the aggregate periods occupied in performing such semi-rotations and stitch-spacing movements being coextensive with the period of operation of the stitch-forming mechanism.

16. In a sewing machine, in combination, stitch-forming mechanism, a rotating mainshaft, a work-holder, means for producing relative feeding movements between the stitch-forming mechanism and the workholder including driving and driven elements, a constant driving connection be tween said driving element and said rotating mainshaft, pin-members carried by said driving element, complemental coacting members carried by the driven element and shaped to permit the imparting of driving impulses to said driven member preceded by dwells, said driving element being actuated from said rotating shaft through said constant driving connection whereby lost motion therebetween is avoided, and said driven element positively controlling the driving element during said dwell.

17. In a sewing machine in combination stitclrforming mechanism, a work-holder, and means for producing relative feeding movements between the stitch-forming mechanism and the work-holder including driving and driven elements, pins carried by the driving element and movable in a circular path, and coacting teeth carried by the driven element, said teeth being shaped to permit the pins to be engaged therewith without imparting movement for an appreciable interval to said driven member.

18. In a sewingmachine in combination stitch-forming mechanism a work-holder, and means for producing relative feeding movements between the stitch-forming mechanism and the work-holder including a rotating driving element and a driven element said elements having coacting surfaces and said rotating driving element turning on an axis located between two concentric circles bounding the outer and inner extremities of the coacting surfaces of the driven element whereby in operation dwells precede the driving impulses imparted to the driven member.

19. In a sewing machlne 1n comblnatlon, stitch-forming mechanism, a work-holder,

and means for producing relative feeding movements between the stitch-forming mechanism and the work-holder includ ng a driving member having a pair of elements driven member may be interrupted by dwells,

of definite and appreciable duration.

In testimony whereof, I have signed my name to thls speclfication 1n the presence of two subscribing witnesses.

EDWARD B. ALLEN.

Witnesses:

,HERBER'I MoBnnN, STANLEY N. SMITH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. G.

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