US2107270A - Buttonhole sewing machine - Google Patents

Description

Feb. 8, 1938; E. B. ALLEN ET AL v BUTTONHOLE SEWING MACHINE Filed No). '10, 1956 13 Sheets-Sheet 2 awn/whom [award 5. A/len, Deceased Joseph/he I44 A//e/1, Aa'mx. Maurice 0. know, and Haro/a C. Fall/khan Feb. 8, 1938. E. B. ALLEN ET AL 2,107,270

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BUTTONHOLE SEWING MACHINE E. B. ALLEN ET AL ,270

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Feb. 8, 1938. E ALLEN AL 2,107,270

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BUTTONHOLE SEWING MACHINE Filed Nov. 10, 1936 1s Sheets-Sheet 1o Edward 5.A//e/7, De'ceaseb Joseph/he Hf l4//en, Admx. Mara/"ice 0. Max, and f/ara/d C. Fau/kna/r Feb. s; 1938. E. B. ALLEN- ET AL 2,107,270

BUTTONHOLE SEWING MACHINE Filed Nov. 10, 1936 13 Sheets-Sheet 11 grwmbom Edward B. A//en, Decease dose obin I1. Awe/7, Admm. Mauq/ae 0. Know, and I Harv/d C. Foal/knew:

Feb. 8, 1938. E. B. ALLEN ET AL BUTTQNHOLE SEWING MACHINE Filed NOV. 10, 1936 13 Sheets-Sheet 12 Feb. 8, 1938.

E. B. ALLEN ET AL 2,107,270

' BUTTONHOLE SEWING MACHINE Filed Nov. 10, 1956 13 Sheets-She et 15 /l l llllllllld Wm" & I

Z 4a fawara B. A/len, Deceased v Joseph/he I44 ,4//en, Aamx.

Mam/"Ilse 0. Knox, and Hare/o C. Fara knew Patented Feb. 8, 1938 BUTTONH OLE SEWING MACHINE Edward B. Allen, deceased, late of Newtown, Conn., by Josephine W. Allen, administratrix, Newtown, Conn., and Maurice D. Knox, Devon, and Harold C. Faulkner, Long Hill, Conn., assignors to The Singer Manufacturing Company, Elizabeth, N. J., a. corporation of New Jersey Application November 10, 1936, Serial No. 110,026

15 Claims.

This invention relates to sewing machines, more particularly of the buttonhole type, and has for an object to provide an automatic lock-stitch eyelet-end buttonhole sewing machine which will sew a lock-stitch buttonhole having radially disposed stitches at one end, which may be an eyeletend, and a bar at the other end. Such a buttonhole is particularly adapted for use in white goods, such as collars and cuffs, as the eyelet-end provides clearance for the shank of the usual collar or cuff button. A further object of the invention is to provide a machine which may be readily converted to sew lock-stitch eyelet-end squarebarred buttonholes of various lengths within the capacity of the machine. A still further object of the invention is to provide means to vary the number of barring stitches at the barred end of the buttonhole.

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 and the advantages attained thereby will be readily-understood by those skilled in the art.

In the accompanying drawings Fig. 1 is-a right side elevation of a buttonhole sewing machine, embodying the invention. Fig. 2 is a top plan view of a lock-stitch pyramid-purl eyelet-end, square-barred buttonhole produced by the machine of Fig. 1. Fig. 3 is a left side elevation of the machine. Fig. 4 is an enlarged view of the bar-stitch counting mechanism of the machine. Fig. 5 is a front end elevation of the machine. Fig. 6 is a rear end elevation of the machine. Fig. '7 is a bottom plan view of the machine. Fig. '7 is a detail bottom plan view of the rapid-feed I clutch-operating armshown in Fig. '7. Fig. 8 is a horizontal sectional view through the bracket- I view of the clutch shown in Fig. 12. Fig. 14 is a A Fig. is a arm standard of the machine, showing the bed in plan. Fig. 9 is a horizontal sectional view through the bar-stitch counting mechanism. Fig. 9 is a face view of an element of Fig. 9.

Fig. 10 is a transverse vertical section through the machine bed substantially on the line Ill-l0, Fig. '7. Fig. 10 is a reverse view of a latch element of Fig. 10. Fig. 11 is a similar section substantially on the line lI-ll, Fig. '7. Fig. 12 is an axial section through the feed throw-out clutch shown in Figs. '7 and 11. Fig. 13 is a bottom face section on the line l4-l4, Fig. 11. section on the line l5-l5, Fig. 11. Fig. 16 is an axial section through the feed throw-out clutchdriving shaft. Fig. 1'7 is a vertical section taken longitudinally of the machine bed through the shuttle mechanism mounted therein. Fig. 18 is an elevation of the parts shown in Fig. 17 looking from the right. through the shuttle-carrying turret looking at the face of the shuttle.

Fig. 20 is a section on the line 20-20, Fig. 1'7. Fig. 21 is a section on the line ill-2|, Fig. 19. Fig. 22 is a section on the line 22-22, Fig. 19. Fig. 23 is a top plan view of the overhanging bracket-arm of the machine. spective view of the shuttle-driver. Fig. 25 is a perspective view of the shuttle-body. Fig. 26 is a side elevation of the needle-vibrating mechanism. Fig. 2'7 is a section on the line 21-21, Fig. 26. Fig. 28 is a vertical section on the line 28-28, Fig. 26. Fig. 29 is a section on the line 29-29, Fig. 28.

Fig. 30 is an elevation of the lower end of the needle-bar showing the yoke and needle-clamp block. Fig. 31 is a perspective view of the rotary needle-bar-bushing. Fig. 32 is a perspectiveview of the laterally reciprocatory guide-block for the needle-clamp-block. Fig. 33 is a vertical section on the line 33-33, Fig. 23. Fig. 34 is a section on the line 34-34, Fig. 33. Fig. 35 is a perspective view of an element of Figs. 33 and 34. Fig. 36 is'an inner face View of the readily-removable and replaceable pattern wheel, together with associated parts of the rapid-feed throw-out mechanism controlled thereby. Fig. 3'7 is a top plan view of the removable pattern-cam and the lever which is actuated thereby to stop the feed of the work-clamp and initiate the square-bar-stitching operation at the 'end of the buttonhole. Fig. 38 is a side elevation of the buttonhole cutter levers and their actuating cams. Fig. 39 is a. transverse vertical section through the work-supporting plates of the work-clamp, showing the buttonhole cutter levers in front end elevation. Fig. 39 is a detail sectional view of an element of Fig. 39. Fig. 40 is a fragmentary view of the portion of the bed-casting which carries the turret supporting bearing, and Fig .41 is a section on the line 4l-4l, Fig. 1'7.

The machine frame comprises the hollow boxlike bed I from one end of which rises the standard 2 of the overhanging bracket-arm 3 terminating in the head 4.

Journaled within and lengthwise of the bed I, is the main sewing shaft 5, Fig. 1, which, through the one-to-one bevel gears 6, I, drives the vertical shaft 8 journaled within the standard Fig. 19 is a vertical section Fig. 24 is a per-' 2. The shaft 8 has a one-to-two speed-multiplying bevel-gear driving connection 9 with the upper or needle-bar-reciprocating shaft H] which is journaled within and lengthwise of the bracket-arm 3 and has the usual crank II and linkconnection |2 with the vertically reciprocatory hollow needle-bar l3 mounted in the head 4.

The hollow needle-bar l3, Figs. 28 and 30, has fixed to its lower end the yoke |4 carrying the cross-pin l5 on which is slidably mounted the needle-clamp-block |6 having at its upper end a guideway 1, Fig. 28, embracing the horizontal member of the yoke I4. The block |6 carries the eye-pointed. needle I8. The yoke I 4 is slidably received at one end in the guideway l9, Figs. 29 and 31, in a vertical arm 20 depending from a block 2| fixed to the-lower end of the needle-bar-bearing bushing 22 journaled in the head 4 and having the pinion 23 fixed to its upper end, whereby turning movements may be imparted to it, as hereinafter explained, as in stitching around the eyelet-end of a buttonhole.

The block 2| also has depending from it another arm 24 which is spaced from the arm 20. The arms 24 and 20 carry a cross-pin 25 on which is horizontally slidably mounted a vertical guide arm 26 having a guideway 21 receiving the spaced rearward extensions 28 of the needleclamp-block l6. The guide-block 26 is steadied on the cross-pin 25 by having its upwardly extending end 26 slidably received in a guideway 26", Fig. 28, in the block 2|; said guideway being completed by the cover-plate 26. The needle I8 is thus supported for endwise reciprocator y and laterally vibratory movements in a rotary support which is turnable about a vertical axis.

The vertical guide-block 26, which imparts the lateral vibratory movements to the needle-clampblock I6, is connected bya link 29, Fig. 26,-of adjustable length to an arm 29 fixed to one end of a rock-shaft 30 journaled in the block 2| and having fixed to its other end an arm 3|, Fig. 2'7, which pivotally carries a guide-block 32 received in the circular groove 33 in the ring member 34 fixed to the lower end of the vertical slide-rod' 35, Fig. 5, journaled in the head 4. The ring 34 is steadied bythe fixed guide-pin 36' which it slidablyengages. Thus, vertical movements of the slide-rod 35 and ring 34, impart lateral vibratory movements to the needle l8 in any position of the plane of vibration of the latter.

The rod 35 is reciprocated vertically, to impart lateral vibratory movements to the needle l8, by the following mechanism. Clamped to the rod 35 is a block 31, Fig. 5, which extends laterally through a slot 38 in one side wall of the head 4 and has pivotally connected thereto one end of a link 39 the other end of which is adjustably and pivotally secured in the slotted segmental arm 40 of a bell-crank lever 48, 4| fulcrumed at 42 on the head 4. The arm 4| of the bell-crank lever is connected by the link 43 to the crank-pin 44 projecting from the'outer face of a crankhead 45 pivoted at 46, Fig. 34, on the disk=shaped head 41, Fig. 33, at one end of the hollow shaft 48 journaled within and transversely of the bracket-arm standard 2. Movement of the crankhead 45 about the pivot-screw 46 changes the ecturnside-stitching operation on the buttonhole the amplitude of needle-vibrationis increased to sew the square-bar stitches 56 and this is done by mechanism to be hereinafter described which operates the lever 51, Figs. 3, 5 and 6, fulcrumed at 58 on the machine frame and carrying at its upper end an endwise adjustable tappet-screw 59, Fig. 33, adapted to push against the free end of the push-rod 52. The means for imparting intermittent semi-rotational impulses to the crank-shaft 48 will be hereinafter described.

Detachably mounted on the transverse frame member 60', within the bed I, is the turret carrier block 6| having the upper and lower spaced bearings 62, 63 for the tubular stem 64 of the turret 65 carrying the yieldingly separable shut.- tle race rings 66, 61, Fig. 21, in which is journaled the conventional sewing machine shuttle 68 carrying the usual bobbin 69, Fig. 17, of under thread. The shuttle 68 is oscillated in its raceway by means of a shuttle driver 16 of usual form which is carried by the shaft 1| journaled in the bearing 12 at the rear of the turret 65. The shaft 1| has pinned to it a pinion 13 meshing with the sector gear 14 fixed to one of the trunnions 15, Fig. 22, of the rocking sleeve 16 journaled in the turret 65. The sleeve 16 is entered by the pin 11 the bifurcated head 18 of which is pivoted at 19 to the upper end of the reciprocatory rod slidable in the turret stem 64.

Screwed to the longitudinally ribbed face 8|, Figs. 17, 20 and 41, of the rod 80 are two spaced gibs 82 which extend outwardly through the slot 83 in the tubular stem 64 of the turret and embrace the ring member 84 which surrounds the stem 64. The ring member 84 is carried by the naled in the carrier 9| which, in turn, is journaled on the bearing bushing 92 in'which the main sewing shaft 5 is journaled. The bushing 92 is set intoan aperture 93 in the frame member 60. The shaft has fixed to it a. pinion 94 driven by the gear 95 of double its size on the main shaft 5.

In order to compensate the shuttle mechanism for the different lateral positions of the needle, provision is made to accelerate and retard the shuttle driving shaft 90' so that the shuttle beak will be properly timed relative to the needle in the different lateral positions of the needle. To this end there is mounted on the main sewing shaft 5 an eccentric 96 embraced by the eccentric-follower lever 91 the forked lower end of which slidably embraces the anchor-block 98 fixed to the rockable pin 99 journaled in the frame block 108, Fig. 40, screwed to the frame cross-member 66. The upper forked end of the lever 91 embraces the block |8| rotatively' free on the shaft 90 and confined between the collar L02, Fig. 17, and the head of the screw I93; 'lIhus, rotation of the main shaft 5 imparts oscillatory movement to the carrier 9| for the crank-shaft 90 which latter is given two rotations-for one complete to-and-fro oscillation of the carrier 9I. The amount of compensation is chosen to be intermediate the exact compensations required for the needle in sewing the side stitches of the buttonhole and the barring stitches across the end of the buttonhole. In other words, the shuttle is slightly over-compensated when sewing the side stitches and eyeletend of the buttonhole and is slightly under-compensated when sewing the longer barring stitches across the end of the buttonhole. This average compensation is found to be quite satisfactory and avoids the necessity of complicating the mechanism to secure exact compensation for all amplitudes of needle-vibration.

The shuttle thread is delivered through the apertured end of the thread-case arm I04, Fig. 19, in which the usual bobbin 69 is housed; the arm I04'being freely received in the notch I05 in the plate I06 screwed to the outer shuttle race ring 61 which is pressed by the springs I01 against the inner shuttle race ring 66., The thread-case I08 is thus restrained from oscillating with the shuttle 68. There is mounted on the vertical back-plate I09 of the shuttle race, Fig. 18, the shank I I of the button-like needle-throat member III formed with the needle-receiving slot II2. The needle-throat member or button III rises through the work-exposing slot II3, Figs. 8 and 39, in the lower clamp-plates II 4 and supports the Work against the thrusts of the needle The turret 65 and needle-bar-rotating bushing 22 are coaxially mounted and are turned in unison by the usual means, to position the stitches radially around one end, for example, the eyeletend of the buttonhole. The turret pinion H is engaged by the sector gear II6, Fig. 7, which is fixed to the lower end of the rock-shaft II1, Fig. 18, journaled in the bearing block I I8 screwed to the frame cross-member 60. Secured to the upper end of the rock-shaft H1 is the arm II9 which is connected by the link I20 to the arm I2 I, Fig. '7, of a lever I22 fixed to the lower end of the upright shaft I23 and having a follower I24 entering the radial stitch-positioning cam-groove I25 in the feed-wheel I26 mounted within the bed I. The upright shaft I23 carries an arm I21, Fig. 23, at its upper end, which arm is connected by the link I28 to the sector gear I29 meshing with the pinion 23 of the needle-bar-turning carrier-bushing 22.

The work-clamp is of the usual construction disclosed in the Allen Reissue Patent No. 15,324. The lower'clamp-plates II4 which carry the upper clamp-feet I30 are mounted on the cross.- slide plate I3I, Fig. 7 which slides laterally of the machine bed on the cross-rod I32 of the longitudinal slide-frame I33. The longitudinal slide frame of the present machine preferably carries the slide-rod I34 which is guided in the bed lugs I35, I36, Fig. 3.

Travelling movements lengthwise of the bed I are imparted to the longitudinal slide frame I33 by means of the longitudinal feed cam-groove I81 in the feed-wheel I26. The cam groove I31 is entered by the follower roll I38 on the lever I39 fulcrumed at I40 on the bed I and connected by the link I4I to the longitudinal slide frame I33. The travelling movement of the longitudinal slide frame I33 is sufficient, not only, to space the stitches lengthwise of the buttonhole, but also .to carry the work-clamp to and fro between stitching position and buttonhole cutting position where the buttonhole cutters may operate on the work without interfering with the stitchforming instrumentalities.

The work-clamp receives its lateral movements as followsz-Secured to the cross-slide plate I3I is an extension-plate I42 the head I43 of which is formed witha groove I44 extending lengthwise of the bed I. This groove I44 is entered by the block I45 on the pin I46 mounted at the front end of the lever I41 fulcrumed at I48 on the frame lug I49. The lever I41 carries at its rearward end the vertical spring depressed slide-bolt I50 which in its lower position enters the lateral feed cam groove I5I in the control or pattern wheel I52 which is removably mounted on the crossshaft I53 journaled in the bed I. The cross-shaft I53 carries a bevel-gear I54 which meshes with the bevel gear I55 fast to the feed-wheel I26. The feed-wheel I26 and removable control or pattern wheel I52 are thus geared together in oneto-one driving relation to rotate in unison, each making one complete rotation per buttonholeproducing cycle.

The wavy portion of the cam track I5I shown in Fig. '7 is the portion which controls the sideshift movements of the work-clamp in sewing around the eyelet-end of a buttonhole. The camtrack I5I has a widened portion I56, Fig. 5, which permits the follower lever I41 to be suddenly shifted to centralize the work-clamp at the end of the second side-stitching operation on the buttonhole for the square-bar stitching operation. The means for so shifting the lever I41 comprises a block I51, Figs. 36 and 37, having a doubly beveled nose I58 and a plate-like shank I59 which is secured to the pattern cam I52. When the second side-stitching operation is completed the beveled nose I58 of the block I51 engages the lever I41, Fig. 37, and suddenly shifts it to the left or in a direction to centralize the work-clamp relative to the field of lateral vibration of the needle; this motion of the lever I41 being permitted by the widened portion I56 of the cam-groove I5I and yieldingly resisted by the biasing spring I60, Fig. 3. At this same time the other side of the nose I58, Fig. 37, engages and swings the lever I6I which is fulcrumed at I62 on the bed I and which engages and shifts the lever 51 to increase the amplitude of vibration of the needle for the barstitching operation.

The main sewing shaft 5 is controlled as to its period of operation by means of a stop-motion device of the usual construction disclosed in said Allen reissued patent. Such a stop-motion device comprises the stop-lever I63 fixed to the rock-shaft I64 and carrying the vertically slidable stop-tooth I65 which engages the notched stop-cam I66 associated with suitable clutchmechanism (not shown) within the continuously running belt-pulley I61. When the stop-motion lever I63 is in its'full-line position, Fig. 3, the main sewing shaft 5 and the stitch-forming mechanism driven thereby are at rest. When the stop-motion lever I63 is shifted to its dotted line or running position, the stitch-forming mechanism is started. To shift thestop-motion to running position the rock-shaft I64 has fixed to it a depending crank-arm I68 which is connected by a link I69, such as disclosed in the Allen Patent No. 1,504,306, of Aug. 12, 1924, to a lever I fulcrumed at I1I on the bed I and having a follower nose I12 in position to be engaged by the cam incline I13 on the pattern wheel I52. When the stop-motion lever I83 is shifted to running position by the cam incline I13, it is retained in such position by the en' gagement of the nose of the spring energized bell-crank latch-lever I14 with the notch I15 in the link I69. At the end of the sewing operation the spring latch I14 is tripped to stop the stitch-forming mechanism by the bar-stitch counting mechanism to be hereinafter described.

During the sewing of the sides and eyelet-end of the buttonhole, the connected feed-wheel I28 and pattern-wheel I52 incorporating the longitudinal feed-cam I31, the lateral feed-cam I 5| and the radial stitch-positioning cam I25 are given a step-by-step rotary motion by mechanism driven by the main sewing shaft, asfollows:The bevel gear 1 at the lower end of the upright shaft 8 is provided at its under face with two diametrically opposed pins I18, Figs. 11, 12, 14, 15 and 16, which impart step-by-step rotary motion to the star-wheel I11 fixed to the upper end of the sleeve-shaft I18 journaled in the frame spider I19. The sleeve-shaft I18 has fixed to its lower end, Fig. 12, the external or live ring-element I80 of a roll-type friction clutch of known construction. The live clutch element I80 has formed integral with it a gear I80 which meshes with the pinion I8I, Fig. 11, fixed to the lower end of the shaft I82 to the upper end of which, Fig. 33, is fixed the bevel gear I83 meshing with the bevel pinion I84 of half its size fixed to the sleeve shaft 48 which imparts lateral vibratory movements to the needle.

Disposed within the live clutch-element I80, Fig. 13, are the usual spring-pressed cylindrical clutch rolls I85 disposed in the clutch-pockets I88 of the driven element or clutch-spider I81 fixed to the driven shaft I88 which is journaled within the sleeve-shaft I18. The clutch rolls are shifted to de-clutching position by the levers I89 the tails I90 of which are expanded by the cone I9I which is slidable vertically on the lower end of the shaft I88 and has a peripheral groove I92 entered by the roller stud I93, Figs. '1, 10 and 11, on the stitching feed-clutch operating lever I94 fulcrumed on the stud I95 carried by the frame lug I98. The clutch-operating lever I94, Fig. 10, extends outwardly through a slot I91 in the machine bed, and is biased upwardly to de-clutching position by the spring I98. The lever I94 is retained in its lower or clutching position by means of a spring-pressed latch-lever I99 fulcrumed at 200 and having a notch 20I in its lower end which is engaged by a lateral tooth 202 on a plate 203 screwed to the lever I94. When the -latch-lever I99 is tripped, the clutchlever I94 is released-and is drawn upwardly by its spring I98 to de-clutch the shaft I88 from the pin and star-wheel drive mechanism which is driven by the main sewing shaft 5.

The shaft I88 which is under control of the stitching-feed clutch, is connected to drive the feed-wheel mechanism, as followsz-The shaft I88 has fixed to its upper end a pinion 204 meshing with a gear 205 fixed to a short shaft 206 having a pinion 201 at its upper end. The pinion 201 is connected by the gear 208, Fig. '7, to th feed-wheel gear 209.

As the purpose of the clutch-mechanism above described is to disconnect the feed and pattern wheels from the sewing shaft 5 during the squarebarstitching operation across the finishing end of the buttonhole, the de-clutching latch lever I99 is arranged to be tripped by the swinging motion of the levers 51 and I8I, Fig. 3'1, derived of lateral vibration, sews from the bevel-nosed block I51 on the pattern wheel. It will be understood that simultaneously with the shifting of the the Work-clamp to its central position, the feed and pattern wheels are disconnected from their driving means and stand still, while the needle, with increased amplitude the final or barring stitches.

The number of barring stitches is controlled by a bar-stitch counting mechanism, as follows:- Fixed to the side of the machine bed is a studpin 2I0, Fig. 9, which has freely mounted thereon the lever 2H and the peripherally toothed sector 2I2 the latter having a recess housing a biasing spring 2I3 which tends to turn the sector 2I2 in a counterclockwise direction, Fig. 4, and initially retains the shoulder 2I2 on the sector 2I2 in engagement with the stop-arm 2I4 carried by the lever 2I5 fulcrumed for adjustment on the pin H0. The lever H5 is adjustable about its fulcrum and is retained in adjusted po- 'sition by the screw 2I6 which passes through the arcuate slot 2I1 in the lever. A pointer2l8, Fig. 3, on the lever plays over a scale which may be graduated to indicate the number of barring stitches to be made. The actuating lever 2, Figs. 9 and 9 carries a pivot-screw 2I 9 on which is mounted the pawl 220 adapted to engage the teeth of the sector 2I2. The pawl 220 has a tail 22I which is biased by the spring 222 in a direction to press the pawl 220 against the toothed sector 2I2. The actuating lever 2 has a ballstud 223 which is. embraced by the lower end of a link 224 the slotted upper end of which is entered by the screw-stud 225 on the free outer end of the rapid-feed clutch-operator push-bar 228, Fig. 11, the inner end of which is pivoted at 221 to the upstanding arm 228 01a bell-crank lever, the forked arm 229 of which embraces the crank 230 on the rapid-feed shaft 23I which is continuously driven by the usual gear-connections 232, Fig. 6, with the gear 233 fast to the belt-pulley I61. The push-bar 226 thus receives constant endwise reciprocatory motion and is biased upwardly by the spring 226' into sliding engagement with the overhanging'latch 234, Fig. 38, which is fulcrumed at 235 on the bed I. The

endwise reciprocations of the push-bar 228, Fig.

11, 'while engaged by the latch 234, imparts through the link 224 an oscillatory movement to the lever 2 of the bar-stitch-counting mechanism. The amplitude of this oscillatory movement is a little greater than the angular spacing of the teeth of the sector 2I2 so that when the pawl 220 engages the sector 2I2 the latter will be advanced by the pawl 220 one tooth at a time. I

At all times except when the barring stitches are being sewn, the pawl-carrying lever 2| I is oscillated idly; the pawl 220 being held out of engagement with the toothed sector 2 I 2 by means of the tail piece 236 which engages the holding pawl 231 on the lever 238 fulcrumed at 239 and having an arm 240 which engages under the clutch-operating lever I94, Fig. 4-. The holding pawl lever 238 is biased by the spring 2 in a direction to carry the pawl 231 toward the toothed disk 2I2,

Whenthe latch I99 is tripped by the lever I6I, Fig. 3'1, to stop the feed and pattern wheels for the barring operation, the up-motion of the clutch-operating lever I94 allows the holding pawl 231 and the actuating pawl 220 to both engage the toothed sector 2I2. Projecting downwardly from the hub of the toothed sector 2l2 75 is an arm 242 which is connected to the spring 243 anchored to the frame. This spring causes the lower end of the slot in the link 224, Fig. 11, to engage the screw-pin 225 on the push-bar 226 at all times except momentarily when the pushbar 226 is released by its hold-down latch 234 to throw in the rapid feed mechanism to be described, whereby the feed and pattern wheels are given a rapid motion both before and after the sewing operation to carry the work-clamp rapidly up to and away from the stitch-forming mechanism. When the bar-stitch-counting mechanism is in operation, the toothed sector 2I2 is advanced one tooth at a time until the shoulder 244 thereon, Fig. 4, engages and trips the latch-lever I14 which releases the stop-motion lever I63 and allows the latter to move to stopping position. The stop 245, Fig. 4, is arranged to arrest the arm 242 when the reciprocating bar 226 is released from its latch 234 for the rapid-feed throw-in operation.

The rapid-feed mechanism is of the conventional construction disclosed in the said Allen reissued patent and in the Allen Patent No. 1,807,577, of May 26, 1931. The rapid-feed shaft 23I carries the worm 246, Fig. 1, which drives the gear 241 connected to the live element 248, Fig. 7, of a clutch on the cross-shaft I53. This clutch includes the cone element 249 which is actuated by the clutch-operating arm 258 on the slide-rod 25I. The slide-rod 25I is biased endwise by the spring 252, Fig. '7, in a direction to de-clutch the cross-shaft I53 from the rapid-feed shaft 23L The clutch arm 258, Fig. 7 carries a stud-pin 253 having two separate portions 253 and 253 the portion 253 of which, when the reciprocat-.

ing clutch-operator bar 226, Fig. 11, is released by the latch 234, is engaged by the shoulder 254,

.When the slide-rod 25I and clutch-shifter arm 258 are shifted to the left, Fig. 10, to start the rapid feed at the completion of the bar-stitching operation, the portion 253 of the stud-pin 253 engages the inclined edge 26I of the. lever I94 and depresses such lever into engagement ,with its latch I99, thus reclutching the feed and pattern-wheels with the main sewing shaft 5 for the next sewing period. The rapid-feed latch-lever 256 is connected as usual to the lever 262, Fig. 36, which is engaged by the usual rapid-feed throwout tripping points 263, 264 on the pattern wheel.

The rapid-feed throw-in latch 234, Fig. 36, is actuated as usual by the arm 265 on the rockshaft 266 which carries the arms 261 and 268, Fig, 1, arranged for engagement, respectively, by the usual 3-armed clamp-closing lever 269 and stop-motion actuated arm 218, such as disclosed in Said Allen Patent No. 1,807,577.

and 39, carrying, respectively, the punch 213 and apertured die 214, are fulcrumed at 215 on the cutter-carrier block 216 which is slidable in ways 211 in the bed I and is actuated by a link cow nection 218 with the cutter-advancing and retracting cam 219 on the one-rotation cutter shaft 288 journaled transversely of the standard 2. The cutter shaft 288 also carries the cutter-closing cams 28I, 282 which engage the rear ends of the respective cutter-levers 21I, 212 and spread them in the usual manner to close the cutter members 213 and 214,

The cutter-shaft is controlled by the usual single rotation clutch device comprising a driven disk 283, Fig. 1,. carrying a radially movable clutch-tooth 284 on the slide 284 which is held in retracted or disengaged position by the usual gate member 285 fulcrumed on the vertical studpin 286. When the gate 285, Fig. 8, is shifted inwardly to release the clutch-tooth-slide 284, the clutch-tooth 284 is engaged by a tooth 281 on the continuously running fiy-wheel 288 and the'cutpull on the starting rod 298, Fig. 1, the slide-bolt 29I carried by the three-armed lever is released by suitably timed mechanism and allowed to enter the cam-groove 289 which imparts one to-andfro swinging impulse to the clamp-closing lever following which the slide-bolt 29I is ejected from the cam-groove 289 and latched in ejected position. In the down-motion of the forwardly extending arm of the clamp-closing lever 269, Fig-1, such arm depresses the arm 292 on the connected rock-shaft sections 293 of the work-clamp and closes the clamp upon the work in a manner well known.

The needle-thread controlling mechanism comprises the take-up lever 294, Fig. .23, which is actuated by the crank 295 and anchored by the link 296 to the frame. The crank 295 is carried by the vertical crank-shaft 291 which is connected by one-to-one bevel gears 298 to the upper shaft I8. The needle-thread t runs through two tension devices 299, 388. Both tensions are on during the sewing of the side stitches, so that the needlethread t is caused to run straight along the top side of the work, Fig. 2, to make the usual pyramid purl stitch.

When the sewing has progressed to the point where the eyelet-end stitches begin, which is substantially at the point where the thin straight portion of the buttonhole slit terminates, the tension 388 is released by the action of the tension-release lever 38I fulcrumed at 382, Figs. 3 and 6, and having a lower end-portion which is engaged and cammed outwardly from dotted line to full line position, Fig. 6, by the taper-nosed collar 382 mounted on and adjustable lengthwise of the rod 382 carried by and forming a rearward extension of the slide-rod I34 which travels longitudinally of the bed I with the workclamp. When the sewing has progressed around the eyelet-end of the buttonhole, the taper-nosed collar 382* travels rearwardly out of engagement with the tension-release lever MI and the tension 388 is restored for the second straight side stitching operation. 4

It has been found by experiment to be very desirable to sew the eyelet-end stitches under less needle-thread tension than the straight side .stitches, in order to avoid the pulling of the needle-thread inwardly around the eyelet-end to a finalposition too close to the slit-stitch needlepunctures. In other words, by reducing the needle-thread tension in sewing around the eyelet-end of a pyramid-purl lock-stitch buttonhole, a finished buttonhole is produced with a minimum of distortion of the pyramid-purl in the region around the eyelet-end of the buttonhole.

When the end of the second side stitching operation is reached and the square-bar stitches 56, Fig. 2, are being sewn the tension 300 is again released by the action of the tension-release lever 30I, the lower laterally bent end 303 of which is engaged by the out-motion of the needle-vibration amplitude control lever 51.

When the sewing is completed, both tensions are released by the up-motion of the conventional stop-motion-controlled tension-release link 304, such as disclosed in said Allen reissued patent. The link 304 is connected at its upper end to a bell- crank lever 305, 306 fulcrumed at 301 on the bracket-arm 3. The arm 306 hasa forwardly curved cam-portion 308, Fig. 23, which is arranged to press inwardly against the tensionrelease lever 30I when the stop-motion device operates to stop the stitch-forming mechanism. The bell-crank lever-arm 306 is also connected by the link 309 to the arm 3I0 of the tension-release rock-shaft 3 which carries the tension-release arm 3 I2 associated with the tension 299.

The machine is equipped with clamp-spreading mechanism and with clamp-opening mechanism, both of the usual construction disclosed in said Allen reissued patent. It is also equipped with the usual finger-starting lever 3I3 which actuates the lever 3I4 connected to the pull-rod 290.

Operation The operator places the work in the open workclamp II4, I30 and presses the starting button 3 I3 which, through the lever 3I4, exerts, a downpull'upon the starting rod 290 and initiates the action of the clamp-closing mechanism. The three-armed lever 269, Fig. 1, receives one complete oscillatory impulse from the cam-groove 289, Fig. 8, in the fly-wheel 288. In the downmotion of the forwardly extending armof such lever, the work-clamp is closed and in the recovery motion of such lever its depending arm depresses the arm 261 on the rock-shaft 266 and trips the latch 234, Fig. 36, to effect the coupling feed and pattern-wheels are driven more slowly of the cross-shaft I53 to the'rapid-feed shaft 23I. The connected feed and pattern wheels I26, I52 are now rapidly driven to effect a rapid forward shift of the work-clamp from its initial retracted position to a' position where the stitching is to begin.

When the work-clamp reaches sewing position, the cam incline I13, Fig. 3, on the pattern wheel I52 engages the follower nose I12 on' the lever I10 and shifts the stop-motion device to dottedline or running'position, in which position it is retained by the latch I14. At the same time the tripping point 264, Fig. 36, acts upon the lever .262 to trip the latch-lever 256, Fig. 10, and effect the throw-out of the rapid feed.

The sewing now proceeds down the first side, around the eyelet-end and back along the return side of the buttonhole, during which sewing the and in step-by-step fashion through the clutch-' connection I19I 81, Fig. 16, with the shafts 8 and 5 which drive the stitch-forming mechanism.

When the-stitching along the return side of the buttonhole reaches a point even with the initial stitches, the beveled nose I58 of the block I 51, Fig; 37, on the pattern-wheel shifts the lever I41 to centralize the work-clamp relative-to the vibrating needle I8 and, simultaneously therewith, shifts the lever I6I to shift the lever 51 and increase the amplitude of vibration of the needle for the bar-stitching operation. The shift of.

of the clutch-lever I94 permits the spring-biased holding-pawl lever 240, Fig. 4, to rise and start the bar-stitch counting mechanism.

When a given number of bar-stitches have been sewn, depending upon the setting of the bar-stitch indicator 2I5, the shoulder 244 of the toothed-sector 2I2, engages the latch I14 and trips the stop-motion device, allowing the stopmotion lever I63 to spring back to its full line or stopping position, Fig. 3, to stop the stitch-forming mechanism. 7

The rising and falling of the stop-motion tooth I65 effected by its engagement with the notched stop-cam I66, Fig. 1, imparts an impulse to the rapid-feed trip-arm 210 which engages and shifts the arm 268 on the rapid-feed start-control shaft 266 to throw-in the rapid feed and effect the rapid return of the work-clamp to its initial position in rear of the stitch-forming mechanism. In this action, the movement of the slide-rod 25I, Fig. 10, to the left carries the stud 253 against the inclined edge 26I of the clutch-control lever I94 and'depresses the latter to reconnect the feedand pattern-wheels to the main-shaft 5 for/ the next buttonhole-producing cycle. Thedown-motion of the lever I94 also carries the arm 240 of the bar-stitch-counting mechanism downwardly to the position shown in Fig. 4 and thus disengages the pawls 220 and 231 from the toothed sector 2I2 which springs back into engagement with its stop 2I4.

When the work-clamp reaches its initial or retracted position, the tripping point 3I5, Fig. 5, 0n the gear wheel I54 swings the lever 3I6 about its fulcrum 3H and shifts the cutter-shaft-control gate 285 inwardly to initiate the action of the cutter-shaft 280 which performs one comproduced.

The needle-thread t, Fig. 23, runs from the ited to the details of construction and relative arrangements of parts shown and described as to increase the amplitude of lateral vibration of various modifications may obviously be made by those skilled in the art within the spirit of the invention.

Having thus SEt ufOI'th the nature of the invention, what we claim herein is:-

1. A lock-stitch buttonhole sewing machine having, in combination,stitch-forminginstrumentalities including an endwise reciprocatory and laterally vibratory needle, a loop-taker, and a bobbin within the field of action of said looptaker, a work-holder, feeding means to relatively move the stitch-forming instrumentalities and work-holder to sew around a buttonhole, means to turn the stitch-forming instrumentalities about an axis normal to the plane of the work in sewing around one end of the buttonhole, and means to cut the buttonhole. 1

2. A lock-stitch buttonhole sewing machine having, in combination, stitch-forming instrumentalities including an endwise reciprocatory and laterally vibratory needle, a loop-taker, and a bobbin within the field of action of said looptaker, a work-holder, feeding mechanism to relatively move the stitch-forming instrumentalities and work-holder to sew around a buttonhole, means to turn the stitch-forming instrumentali ties about an axis normal to the plane of the work in sewing around one end of the buttonhole, means to stop the feeding mechanism and to control the stitch-forming instrumentalities to sew a predetermined number of barring stitches across the other end of the buttonhole, and means to cut the buttonhole.

3. A lock-stitch buttonhole sewing machine having, in combination, stitch-forming instrumentalities including an endwise reciprocatory and laterally vibratory needle, a loop-taker, and a bobbin within the field of action of said looptaker, a work-holder, feeding mechanism to reladetermined number of barring stitches across the other end of the buttonhole, means to cut the buttonhole, and means acting subsequently to the sewing of the barring stitches to reversely turn the stitch-forming mechanism about said axis to restore it to its initial position.

4. A lock-stitch eyelet-end buttonhole sewing machine having, in combination, stitch-forming instrumentalities incinding-anendwise reciprocatory and laterally vibratory needle, a loop-taker, and a bobbin within the field of action of said loop-taker, rotary supporting means for the stitch-forming instrumentalities, a work-clamp, means to relatively move the stitch-forming instrumentalities and work-clamp to sew around a buttonhole, said means including a longitudinal feed-cam, a lateral feed-cam, and a radialstitch positioning cam to turn the stitch-forming instrumentalities about an axis normal to the plane of the work in sewing around one end of the buttonhole, means to drive said cams while the stitch-forming instrumentalities are oper-. ating to sew along the first side, around one end and back along the second side of the buttonhole, means to disconnect said cams from their driving means at the close of thesecond side stitching operation for a bar-stitching operation across the finishing end of the buttonhole; and means the needle for the bar-stitching operation.

5. A lock-stitch eyelet-end buttonhole sewing machine having, in combination, a frame including a bed and an overhanging bracket-arm, stitch-forming instrumentalities'including a reciprocatory and laterally vibratory needle, a shuttle and a bobbin, rotary supporting means for the stitch-forming instrumentalities, a stopmotion device for the stitch-forming instrumentalities, buttonhole cutting mechanism arranged to cut the buttonhole with the work-clamp occupying a buttonhole-cutting position on said bed removed from sewing position, a feed-wheel and longitudinal feed connections for moving the work-clamp from buttonhole-cutting position through sewing position in a direction lengthwise of said bed and the buttonhole to .be stitched, means to start the stitch-forming instrumentalities when the work-clamp arrives at sewing position, means to turn the stitch-forming instrumentalities in sewing around the eyelet-end of thebuttonhole, means to stop the feed-wheel for a square-bar-stitching operation when the workclamp reaches a position in the second sidestitching operation on the buttonhole even with the initial stitch of the buttonhole, means to trip the stop-motion device to stop the stitchforming instrumentalities when the square-barring operation is completed, and means to start the feed-wheel to carry the work-clamp back to buttonhole-cutting position. I

6. A buttonhole sewing machine having, in combination, a frame including a hollow bed, stitch-forming mechanism including an endwise reciprocatory and laterally vibratory needle, a work-clamp, a feed-wheel in said bed and connections to move said Work-clamp, a cross-shaft in said bed, geared one-to-one to said feed-wheel, a control wheel mounted on said cross-shaft ex.- ternally of said bed, and means controlled by said control wheel to increase the amplitude of lateral vibration of the needle in barring one, end of the buttonhole.

'7. A buttonhole sewing machine having, in combination, a frame including a hollow bed, stitch-forming mechanism including an endwise reciprocatory. and laterally vibratory needle, a

work-clamp, a feed-wheel in said bed and connections to move said work-clamp, a cross-shaft in said bed geared one-to-one to said feed-wheel, a control wheel mounted on said cross-shaft externally of said bed, means controlled by said controluwheel to increase the amplitude of lateral vibration of the needle in barring one end of the buttonhole,'and means tripped into actionby said control wheel to count the. number of barring stitches and bring the stitch-forming mechanism to rest after a predetermined number of barring-

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