US2340276A - Buttonhole sewing machine - Google Patents

Description

Jan. 25, 1944. E. P. SPAINE EI'AL BUTT-ONHOLE SEWING MACHINE Filed May 16, 1942 5 Sheets-Sheet l and J/arold 6. E7aulbner Jan. 25, 1944.

E.'P. $PA|NE EI 'AL 2,340,276 BUTTONHOLE SEWING MACHINE Filed May is, 1942 1 s Shets-Sheet 4 nus ddwaufd Spwz'ne and Jazcrolal C. Sue-61b1,

Patented Jan. 25, 1944 BUTTONHOLEV SEWING MACHINE Edward P. Spaine and Harold C. Faulkner, Bridgeport, Co nn., assignors to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application May 16, 1942, Serial No. 443,236 v 17 Claims.

This invention relates to sewing machines;

more particularly of the buttonhole type, which are adapted to sew a buttonhole having radially disposed stitches'at one end, which may be an eyelet end, and a bar at the other end. The bar may be produced by the sewing machine which effects the production of thebuttonhole or by 'a separate barring machine in 'asubsequent operation.

The primary object of the present invention is to provide novel means automatically operable during the production of the radially disposed stitches to vary the relative feed between the needle and the work to provide for making a greater or less number of stitches at the eye-end of the buttonhole. f p

A- further object of the invention is to provide means, conveniently and quickly operable, for increasing the spacing between successive stitches in a buttonhole throughout the entire length of the buttonhole.

A still further object of the invention is the provision with a buttonhole sewing machine having a first feeding mechanism for effecting relative shifting between the needle and the work, thereby to space the stitches to form a buttonhole, of a novel second feeding mechanism automatically operable for overfeeding the first feeding mechanism and effective to more widely space the stitches at predetermined portions 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, 7

Fig. 1 is a left side elevational view of a buttonhole sewing machinaembodying the invention.

Fig. 2 is a bottom plan view of the machine. Fig. 3 represents an enlarged vertical sectional view taken through the machine-standard, showing the connections for actuating the clutch of the improvement.

Fig. 4 represents a vertical sectional view taken substantially along the line 4-4, Fig. 3.

Fig. 5 represents a sectional view taken substantially along the line 55, Fig. 4. illustrating the details of the clutch in the improvement.

Fig. 6 represents a sectional view taken substantially along the line 6-8, Fig. 4.

Fig. '7 is a face view of the clutch shown in Figs. 5 and 6, illustrating the relative position 0 the declutching levers and the clutch-rollers, with the release-cam superposed in its proper position to show its preferred shape.

Fig. 8 is a sectional view taken along the line 8-8, Fig. '7.

Fig. 9 is a sectional view', similar to Fig. 4,but'

showing the parts in position'such that the. clutch is in operative position. throughout the entire stitching cycle. f

Fig. 10 represents a vertical sectional view taken substantially along the line Ill-l0, Fig. 1.

Fig. 11 represents a horizontalsectional' view taken substantially along the line I ll I, Fig. 10.

Fig. 12 is a diagrammatic 'view of a buttonhole as produced on the conventional eyelet-end buttonhole sewing machine.

Fig. 13 is a view similar to Fig. 12, showing a buttonhole produced on a sewing machine fitted with the present invention.

Fig. 14 is a view of a buttonhole producediby a buttonhole sewing machine equipped with the present invention adjusted for operation throughout the entire buttonhole-producing cycle.

Fig. 14a is a view of a lapel buttonhole pro--- duce'd on a machine fitted with the present improvement. 3 y

Fig. 15 represents a horizontal sectional view taken substantially along the'line l5-l5, Fig. 1.

' Fig. 16 represents a horizontal sectional view taken substantially along the line Iii-I 6, Fig. 1.

Fig. 17 is a face view of the plate used forindicating the position of adjustment of the pivotal axis of the actuatinglever for either eye-' let-end buttonholes or straight buttonholes.

Fig. 18 is a fragmentary bottom plan view of the usual feed-cam, showing its two driving gears and the toothed clutchfor connecting one of the gears to the feed-cam. I

Fig. 19 represents 'a sectional viewtaken substantially" along the line l9-l9, Fig. 18.

lnithe preferred embodiment of the inventionillustrated, the machine-frame comprises a hol low box-like bed I from one 'end of which rises the standard 2 of an overhanging bracket-arm 3' terminating in a head 4.

' The stitch-forming mechanism is of the Well known type embodying an upper endwise' re-' ciprocatory and laterally vibratory needle 5 and under thread mechanism constructed substantially in accordance with the disclosure of U. S. Patent No. 1,372,473, dated March 22, 1921, and comprising a turret 6, Fig. 1, which is turnable about a vertical axis and carries threaded'andnonthreaded loopers and a pair of loop-detainers- 30, 1915; No. 15,324, reissued April-4, 1922 and No. 1,534,017, April 21, 1925. I The mechanism operates to rotate the stitch forming devices in one direction during the sewing around the eyelet-end of a button hole and to reversely rotate the stitch-forming devices between sewing periods to restore them to initial position. I

The work to be buttonholed is held through the entire buttonhole operation in a work-clamp, in-

dicated as I I, which is of the traveling type; The

work-clampis-first rapidly moved over the bed I to carry the work forwardly from initial or buttonhole-cutting position to stitching position, then more slowly moved in step-by-step fashion to place the stitches about th buttonhole, and then rapidly returned to initial position. The lower portions, or clamp-plates, of the workclamp II are carried by a cross-slide plate l2, Fig. 2, which, in turn, is carried by a longitudinal slide-frame l3 to which traveling movements are imparted by a link-connection M, Fig. 2, with a feed-lever l5 having a follower i5 tracking a feed cam-groove in the feed-cam in. The crossslide plate 12 is shifted by ,a lever I! having the usual connections with the feed-cam I0 and removable pattern-cam IS, the latter of wlnch is secured on the exposed end of a crosseshaft l9 connected by bevel gears and 2|, Fig. 3, to the feed-cam l0, so as to run with the latter. For a more complete disclosure of the above described mechanism reference may be had to the U. S. reissued Patent No. 15,324, April 4, 1922.

The rapid feed of the work-clamp from buttonhole-cutting position to sewing position and return is efiected through the use of the following mechanism: Journaled in the bed I is a constantly running rapid feed drive-shaft 22 geared at one end to a main-shaft 23 rotated by means of belt-driven pulley 24 adapted to operate through a conventional form of clutch and stopmotion device S. Mounted on the rapid feed drive-shaft 22 is a worm 25 in mesh with a gear 26 mounted on the cross-shaft l9. Secured to the gear 26 is the live element 2! of a clutch within which is located a driven element fast upon the cross-shaft I9, which driven element includes a plurality of clutch-dog-operating levers having tails 29. When the tails 29 are expanded by a cone 30, slidable on the cross-shaft I9, the clutch is released and the cross-shaft is disconnected from the rapid-feed drive shaft 22. When the cone 30 is withdrawn from the tails29 of the clutch-dog-operating levers, the clutch is engaged and the shaft I9 is coupled to its drive shaft 22 or, in other words, the rapid-feed is thrown in. Thi rapid-feed mechanism is constructed substantially in accordance with the disclosure of said U. S. Patent Reissue No. 15,324.

'Thecone 30 is shifted axially of th cross-shaft 19, to engage and disengage the clutch, bymeans of an arm 3|, Fig. 2, forked at its free end to embrace the grooved hub 32 of the cone 3!). The other end of the arm 3| is clamped upon a crossslide rod 33 journaled in the bed I and biased by a coil-spring 34 in a direction to throw out the rapid-feed. The cross-slide rod 33 is shoved endwise against the pressure of the spring 34, to throw in the rapid-feed, by the continuously reciprocating push-bar 35 which is pivoted to one arm of a bell-crank 36, the other arm of which is forked and engages a. crank 3! on the rapidfeed drive-shaft 22, Fig. 2. The bell-crank 36 is continuously oscillated about its fulcrum-stud 38 by the crank 31, thus imparting continuous end- "wise movements to the push-bar 35. The endwise movements-of the push-bar 35 ar utilized at predetermined times in the stitching cycle to withdraw the cone 30 from the rapid-feed clutch and thereby effect the couplin of the cross-shaft I9 to thedrive shaft 22. The throw-out of the rapid feed-is accomplished by the coil-sprin 34 which functions to shift the cone toward the rapid-feed clutch and thereby uncouple the crossshaft 1 9 from the drive shaft 22. Suitable latches and trips .(not shown), controlled by the patterncam l3 and thecontinuously running belt-pulley 39, Fig. 2, operate to render operative or inoperative the mechanism for shifting the cone 30. At thecompletion of the stitching operation, the usual stop-motion lever in its movement to 'stop the main-shaft; 23, operates to releasea suitable latch permitting the coil-spring 34 to shift the cone 30 toward the rapid-feed clutch to uncouple the cross-shaft l9 from th drive-shaft 22. It will be understood that the above described rapidfeed is active only during the portions of the cycle immediately preceding and following the sewing period and operates to rapidly'shift the'workclamp to and away from sewing position. The rapid-feed mechanism is of well known construction and is substantially the same as that disclosed in the said Reissue Patent No. 15,324 and the U. S. patent to E. P. Spaine, No. 2,165,016, July 4, 1939.

During the portion of the cycle when the stitchforming mechanism is active, the feed-wheel I0 is driven in a slow step-by-step fashion from the main-shaft 23 through the gears 40, Figs. 1 and 2, from the pin-and-star wheel device 4| which is driven by the main-shaft 23 in the usual manner through the bevel gears 42 and vertical shaft 43 from which the upper or needle-actuating shaft 44 is driven. As fully described in the Reissue Patent No. 15,324, and shown in Figs. 18 and 19 of the accompanying drawings, turning impulses are imparted to the feed-cam II) by one of the gears 48 which is in wesh with a ring-gear 45 sustained for turning movement in a peripheral notch 46, Fig. 18, provided in the under face of the feed-cam i ll. The ring-gear 45 is held in the notch 46 by a plurality of retainers 41, Fig. 19, secured to the peripheral face of the bevel gear 2| integral with the feed-cam I3. Turning impulses imparted to the ring-gear 45 by the meshing gear 40 are transmitted to the feed-cam H] by one of a plurality of pawls 48 pivoted, as at 49, to the under face of the feed-cam l0 and spring-biased into engagement with ratchetteeth 59 formed in the inner face of the ringgear 45. When the stitch-forming mechanism is in operation the ring-gear 45 drives the feedcam through the one-way acting ratchet-andpawl connection above described.

The sequential operation of the rapid-feed mechanism and the slow step-by-step feed mechanism in prior machines of the type disclosed in the said Reissue Patent No. 15,324 is as follows: Upon depressing the starting lever of the machine, the constantly running belt-pulley 39,

through suitable connections, operates to lower the work-clamp ll into work-clamping position and subsequently withdraw the clutch-cone 30 to render the clutch 21 effective tocouple the constantly running rapid-feed drive-shaft 22 to the cross-shaft I 9 and rapidly rotate the feedcam l0. Upon reaching stitching position, the clutch-cone 30 is shifted into clutch-releasing position to throw out the rapid-feed mechanism and, simultaneously, the belt-driven pulley 24 is clutched to rotate the main-shaft 23 which drives the feed-cam l step-by-step fashion and operates the stitching mechanism. At the completion of the stitching operation the slow step-by-step feed is terminated by the declutching of the beltdriven pulley 24 from the main-shaft 23 and the stopping of the main-shaft in a predetermined stop-position by the stop-motion device S. Simultaneously with the stopping of the slow step-bystep feed, the clutch-cone 30 is withdrawn from the tails 29 of the clutch-dog-operating levers to thereby throw in the rapid-feed mechanism which operates to quickly return the completely stitched buttonhole to buttonhole-cutting position. In cut-after machines this buttonholecutting operation is efiected afterthe stitching cycle is completed, while in cut-first machines the buttonhole-cutting operation is efiected before the stitching cycle begins.

The stitch-forming mechanism of the present machine is rotated about a vertical axis to form an eye at one end of the buttonhole. In prior machines the spacing between the successive radial stitches about the eye of the buttonhole has been such that upon reducing the size of the eye, as for example, from the sizeshown in Fig. 12 to the sizes shown in Figs. 13 and 140., without reducing the total number of stitches in the complete buttonhole, the stitches are crowded together, resulting in a bulky eye. The present invention relates to novel means by which the spacing of the stitches around the eye of the buttonhole is controlled. To this end the machine is provided with a third feeding mechanism which, in effect, overdrives the slow step-by-step stitching feed, while the stitches are being formed around the eye of the buttonhole, and imparts to the feed-cam l0 step-by-step turning impulsesof greater amplitude than those imparted to the feed-cam by the slow stitching feed.

The novel third feeding mechanism consists essentially of a train f connections including a clutch, the eifective action of which is automati cally controlled, whereby the feeding mechanism is thrown in and out of action at predetermined times in the cycle. Referring to Figs. 4, and 6, the bevel gear has attached to its inner face, preferably by screws 5 I, a cup-shaped member 52 providing an outer cylindrical clutch-surface 53 substantially concentric with the longitudinal axis of the cross-shaft l9. Disposed within the cup-shaped member 52 is a live internal clutchspider 54 formed preferably with three suitable undercuts or recesses 55 providing inclined surfaces 56. Disposed in each of the recesses 55 is a clutch-element 51 which is engagedby a plunger 58, Fig. 7, backed by a coil-spring 59, the plunger 58 acting to bias the element 51 toward the narrow end of the recess 55 and wedge the same between the inclined surface 56 and the outer clutch-surface 53 of the cup-member 52. As shown in Figs. 5 and 6, the clutch-spider54 is mounted on a sleeve 66 journaled on the crossshaft IS. The spider 54 is oscillated constantly during the operation of the stitchforming devices by means of an actuating lever 6l'secured at one end face-to-face with the spider 54 preferably by means of three screws 62. At its other end the actuating lever 6| is connected by means of a ball-and-socket joint to the lower end of a link 63, Fig. 3, which is connected at its upper end, through a second ball-and-socket joint, to the free end of a vibratory lever 64 pivoted upon a fulcrum-stud 65 and bifurcated to straddle and engage two bearing-blocks 66 embracing a common form of adjustable actuating eccentric 61 fast upon the upper shaft 44. As the upper shaft 44 is rotated the eccentric 61 imparts movement to the lever 64 which, through the link 63, operates the actuaitng lever 6| connected to the live clutch-spider 54. The live clutch-spider 54, through the clutch-elements 51, drives the bevel gear 20 which rotates the feed-cam ID.

The speed with which the third feeding mechanism rotates the feed-cam is dependent upon the amount of eccentricity of the eccentric 61 and the effective length of the vibratory lever 64 between the eccentric 6'1 and the vibratory lever fulcrum-stud 65. As shown in Fig. 15 the eccentricity of the eccentric 61. is adapted to be regulated by means of an adjusting screw 68, whereby the vibratory lever 64 may be actuated through a greater or less are per rotation of the needleactuating shaft 44. To provide forchanging the efiective length of the vibratory lever between the eccentric 61 and the vibratory lever fulcrumstud 65, the latter is formed so that its longitudinal axis is offset to one side of the longitudinal axis of the shank 69, Fig. 15, of the fulcrum-stud which is journaled in a bearing-lug 10 attached to the bracket-arm 3. Pinned to the other end ofv the fulcrum-stud shank 69 is a control-lever H apertured at its free end to receive a detentplunger 12 fitted at one end with a knurled head 13 and at its other end biased by means of a spring 14, Fig. 16, into one of a plurality of locking apertures 15 provided in an index plate I6 attached to the bearing-lug 10. As disclosed in Fig. 17, the index plate 16 with which the present machine is fitted has but two locking apertures 15, one in the lower portion of the index plate for eye buttonholes and another in the upper portion of the index plate for straightbuttonholes. The two locking apertures illustrated are positioned at the extreme limits of adjustm nt and it is to be understood that any number of apertures may be provided in the index plate between the two apertures shown, and that these additional apertures would represent intermediate positions between the two extreme positions. When the detent 12 is positioned as shown in Figs. 3 and 17, the longitudinal axis of the fulcrum-stud 65 is at a maximum distance from the axis of rotation of the eccentric 61, in which case the amplitude of movement of the point of junction of the vibratory lever 64 and the link 63 for a given amount of eccentricity'of'the eccentric 61 is at a minimum. When the detent 1.2 is positioned in the aperture indicated for straight buttonholes the longitudinal axis of the fulcrum-stud 65 is locatedat a minimum distance from the axis of rotation of the eccentric 61;in

which case maximum oscillations are imparted to the clutch-actuating lever 61, thereby to more widely separate the radial stitches about the end of the straight buttonhole.

As previously mentioned the live clutch-spider 54 is continuously operated during the entire'peri- 0d of operation of thestitching mechanism, Automatic means is provided for throwing the clutch .-.inio.;an 'i Qut eteperation to r nde t t i fe din m cha m f t ve. i e t v a predetermined periods in. the buttonhole cycle, Rederring to,Figs, 4, 5,- 6, and'l; it will be observed ,zthat the clutchspider 54 is undercut, as at 71, adjacent each ofwthe three clutch-elements 51 to provide. clearance .for clutch-dog-releasing levers 18 each of which has a cylindrical shank .l9rjournaled in theclutch-spider 54. Preferably pinned to one end of the shank I9 is an arm 80 .to which is mounted a roller 8| adapted to engage the periphery of a release-cam 82, Fig. '7, :mounted for free rotation on the sleeve 66 carried byflthe cross-shaft IS. The. release-cam82 is secured, as by screws 83, face-to-face with a platemember also iournaled upon the sleeve6ll and having a pair of radial arms 85, 86. Attached to the outer end of' the radial arm. 85 is a depending linkfi'i slotted at its lower end to receive a pin 88 fixed in the free end of a lever 89 pivoted at its lower end to an upstanding ear 96 provided on one end of a transversely. shiftable slide 9|, Fig. 10, guided by a block 92 and retained against the milled bottom surface of the bed-reinforcingrib 93 by a pair of plates 94.

Mounted on the lever 89 intermediate its ends -is a roller 95 adapted to be engaged by one of a plurality of face-to-face stacked cams 96, 9'1 fastened, by means of the elongated slot 98 and screw 99 for limited circular adjustment, upon the face of the bevel gear 29, Figs. .7 and 8, and shaped to-rest on the periphery of the clutchmember 52 to prevent turning about the screw 99. Cam 9? is secured to. cam 96 by the screw I66. It will be'understood that as the bevel gear 26 is turned by the bevel gear 2| on the feed-cam II), which is rotated by the gear-train 49 during the stitching of the buttonhole, the cams 96 and 91 are brought into engagement with the roller 95, thus swinging the lever 89 downwardly about its pivotal axis and; through the link 81, turning the :plate-member 8A and the release-cam 82 in a counterclockwise direction as viewed in Fig. 4, against the action of a coil-spring |6| acting between the radial arm 86 and the machine-bed Turning of the release-cam 82 in a counterclockwise direction relative to the rollers 8| on the clutch-dog-releasing levers 18, moves the concentric outer surfaces I02 (Fig. '7) of the releasecam out of range of the rollers 8|, thus enabling the plungers 58 and the springs 59 to urge the clutch-elements into wedging relation between the clutch-spider 54 and the cup-member 52. The concentric inner surfaces I63, Fig. '7, of the release-cam 82 are spaced suificiently near to the axis of the cross-shaft |9 so that the clutch-dog- :releasing levers 18 will in no way interfere with the; wedging action of the clutch-elements 51. When the clutch-elements are free ,to act under theaction of the springs 59, movements imparted to the lever 6| by the eccentric 61. rotate the bevel gear 20 and hence the feed-cam l0 in stepby-step fashion; the extent or amplitude of these step-by-step movements being governed by the eccentricity of the eccentric 61 and the efiective length of the vibratory lever 64. When the stepby-stepimpulses imparted to the feed-cam l0 exceed those delivered by the slow step-by-step stitching feed it will be understood from Figs. 18 and 19 that the pawls 48 and the feed-cam ID, to which the pawls are pivotally secured, turn in a counterclockwise direction, Fig. 18, relativeto thering-gear 45; the pawls 48 riding over the ratchet-teeth 50in a direction not to interfere with-the intermittent rotation of the ring-gear 7 45 which is transmitted to the ring-gear by the gearr-train 46 throughout the entire stitching cycle. In other words, since the turning impulses imparted tothe feed-cam It! by the novel third feedingmechanism exceed those imparted to the feed-cam U) by the slow stitching feed when the clutch of the third feeding mechanism is thrown into effective driving relation with the feed-cam Hi, the third feeding mechanism overdrives the slow stitching feed and increases the spacing between successive-stitches constituting the buttonhole.

In'orderthat the present invention may be utilized on machines adapted to sew either eyelet or straight buttonholes, the lever 89 is supported upon the transverse slide 9| which is adapted to be shifted endwise a limited extent. This limited shifting of the slide 9| is desirable so that when stitching eyelet buttonholes the roller on the lever 89 can be positioned within the range of movement of .the cam 96, or, when stitching straight buttonho1es, the roller 95 can be positioned within the range of movement of the cam 91. Theactive periphery of the cam 96 is of sufficient length to maintain the third feeding mechanism in effective action long enough to properly distribute the radial stitches around the entire eye of the buttonhole. The active periphery of the cam 91 is shorter than that of cam 96 inasmuch as the number of stitches distributed around the end of a straight buttonhole-is less than that required. for the end of an eyelet buttonhole. To insure the same even distribution of radial stitches on the last half of the eye of the buttonhole as on the first half of the eye the outer surface of the cam- assembly 96, 91 adjacent its trailing end is relieved, as indicated at I64, to position the clutch-dog-releasing levers 18 such that they will eiiect a slightly earlier release of the clutch-elements, thereby to shorten the effective stroke of the clutch and compensate for the slight overthrow in the feeding mechanism caused by the inertia of the parts and'the reduction of friction in the work-clamp shifting cam-mechanism.

The means for shifting the slide 9| so that roller 95 will be properly positioned for engagementeither by cam 96 or by cam 91 is best shown in Figs. 10 and 11. Suitably attached to the left hand end-portion of the slide 9| is an upwardly extending lug I65 apertured adjacent its upper end to receive a shift-rod I86 journaled intermediate its ends in the left hand sidewall of the bed I and having fixed on its outer end a head It? by which the shift-rod I66 can-be turned about itslongitudinal axis and shifted endwise. The rod I06 is mounted to turn freely in the lug I05, but is constrainedfrom moving endwise in the lug I65 by a collar I08 and the hub of an arm |||9 of which the free end is connected by a tension-spring to the bed I. Secured on the shift-rod I06 adjacent the head I01 isa stop-arm which is biased by thetension-spring Ill] into cooperation witha selected one of a plurality of stop-notches H2, H3, I M, Fig. 11, formed in an angle-member 5 on the bed The stopnotches are arranged in line, with each suitably labeled as shown inFigs. 10 and 11. When the stop-lever H is positioned as shown in full. lines in Figs. 10 and 11,1. e., with the stop-arm .in the notch I I2 labeled Reg.," the slide 9| is located in its extreme left hand position, in which position the roller 95, Fig. 10, is outside the path of movement of; the cam- assembly 96, 91 and is not affected thereby. With this setting the third usual such as shown in Fig. 13, of the drawings,

the shift-rod I06 is turned sufficiently to move the stop-arm 'IH out of the notch H2, after which the shift-rod I06 is shoved axially to move the roller 95 close to the face of the bevel gear- 20, Fig. 2, and into the path of movement of the cam 96. To maintain the roller 95 so positioned, the stop-arm I I I, when in register with the stopnotch 'I I4, is released and the tension-spring I I biases the stop-arm into the notch I I4, as shown in dotted lines in Fig. 11. With the roller 95 in the position as shown in Fig. 2, the cam 96, at the proper selected time in the stitching cycle, en-

gages the roller 95 and pivots the lever 89, Fig. 4,

about its fulcrum, thereby turning the platemember 84 through the link 81 to a position such that the cam 82, Fig. '7, frees the clutch-dogreleasing levers 18 to permit the clutch-elements 51 to intermittently couple the constantly operating clutch-spider 54 to the cup-member 52 and hence rotate the feed-cam l9 through the bevel gears 20, 2| at a speed in excess of that imparted to the feed-cam by the usual stitching feed.

When it is desired to produce a straight buttonhole having a plurality of radial stitches produced at one end of the buttonhole, such as in the case of lapel buttonholes, Fig. 14a, the shift-rod is positioned so that the end of the stoparm is located in the stop-notch H3, in which position of the stop-arm the roller 95 is moved into the path of travel of the cam 91. a 91 is smaller than cam 96 and hence the period of effective operation of the third feeding mechanism isshorter. V v

In some cases it is desirable to hand-stitch buttonholes. ,To facilitate the hand sewing operation, it is advantageous to baste and cut the buttonholeby machine inpreparing the same for the hand sewing operation. The present invention provides manually operated means bywhich a regular machine may be quickly converted into' a machine suitable for basting buttonholes. To this end, the plate-member 84, Fig. 9, is formed with'a projection I It to which fastened an arm H1 overlying a cam-arm H8 attached at one end to a block 9 secured by means of a setscrew I20 on a rod I21 journaled at its opposite ends in the sidewalls cf the bed I. Secured to the exposed left hand end of the rod I2l is an upstanding handlever I22 by which the rod l2l is adapted to be turned in its bearings to shift the plate-member 84, together with the cam 82, from the position shown in Fig. 4to the position shown in Fig. 9, in which latter position the clutch-dog release levers '18 are freed, thus enabling the clutch-elements 51 to effectively couple the clutch-spider 54 to the cup-member 52 and drive the feed-cam II]. It will be understood that as long as the hand-lever I22 remains in the dotancl-dash position shown in Fig. 9, the third feeding mechanism is eifective and over-drives the slower stitching feed to rotate the feed-cam at a speed such that the stitches constituting the buttonhole are distributed as shown in Fig. 14. After the basting and buttonhole-cutting operations are completed, the buttonhole is finished in Th cam' in the machine.

From the above description it will be understood that the present invention contemplates an automatic mechanism to be incorporated in buttonhole sewing machines adapting the ma chines for producing buttonholes having the stitches around an end of the buttonhole spaced at greater distance apart than along each side thereof. Also, the present invention contemplates a manual control for the above described mechanism by which the same may be rendered effective for any portion of thestitching cycle or for the entire stitching cycle. Further, the novel feeding mechanism is constructed so that, if desired, the step-by-step gear-feed can be rendered inoperative by swinging one of the gears 40 out of meshing relation with its adjacent gear, and the novel feeding mechanism substituted for the gear-feed. Whenthis is done a variation in the total number of stitches constituting the buttonhole can be readily obtained by adjusting the eccentricity of the eccentric 64, the effect of which eccentricity can be augmented by varying the effective length of the lever 64,

Having thus set forth the nature of the invention what we claim herein is:

1. In a sewing machine of the buttonhole type, in. combination, stitch-forming mechanism, a

work-holder, and means to effect relative moveduration of the effective action of said second feeding mechanism.

2. In a sewing machine of the buttonhole type, in combination, stitch-forming mechanism, a work-holder, and means to effect relative movements between said work-holder and stitchforming mechanism to space the stitches about the buttonhole, said means including a first feeding mechanism to relatively move the stitchforming mechanism and work-holder progressively in sewing a portionof the buttonhole, a second feeding mechanism to relatively move the stitch-forming mechanism and the work-holder progressively in sewing about another portion of the buttonhole, a plurality of cams, means controlled by a selected one of said cams for throwing said second feeding mechanism into and out of effective operation, and manually shiftable means for rendering any one of said cams fiective. p l

3. In a sewing machine of the buttonhole type, in combination, stitch-forming mechanism, a work-holder, and means to effect relative movements between said work-holder and stitchforming mechanism to space the stitches about the buttonhole, said means including a pair of constantly actuated separate feedingmechanisms successively rendered effective forproducing a a subsequent hand sewing operation. Obviously,

progressive relative, movement between said" stitch-formingmechanism and' work-holder duringrthe formation of the stitches'along the side portions and around one end-portion of the buttonhole, and automatic means for rendering-one of said feeding mechanisms effective to overfeed the other of said feeding mechanisms during a portion of the cycle of stitches made around the' buttonhole.

4. In a buttonhole sewing machine, the combination with stitch-forming mechanism and a work-holder which are relatively movable to space the stitches about a buttonhole of a first feeding mechanism'to relatively move the stitchforming mechanism and work-holder progressively in sewing a portion of the'buttonh'ole, a second feeding mechanism to relatively move'the stitch-forming mechanism andiwork-holder progressively in sewing anotherportion of the buttonhole, said second feeding mechanism including a step-by-step driving element constantly actuated during the entire stitching cycle, and automatic means operable to render effective said constantly actuated element to drive said second feeding mechanism for a predetermined portion of the stitching cycle.

5. In a sewing machine of the buttonhole type, the combination with stitch-forming mechanism and a work-holder which are relatively movable to space the stitches about a buttonhole, a feed- 1 cam for effecting a relative movement between said stitch-forming mechanism and said Workholder, a transverse rotary shaft, and means connecting said rotary shaft with said feed-cam, of

means for imparting a continuous rotary motion to said transverse shaft for a portion of the buttonholing cycle to drivesaid feed-cam, and means for imparting an intermittent rotary mo-. tion to said'transverse shaft for another portion of the buttonhcling cycle also to drive said feedcam.

6. A sewing machine having stitch-forming mechanism and a work-holder which are relatively movable to space the stitches, a rotary shaft, and feeding means for effecting progressive relative movementbetween the stitch-forming mechanism and the workhol'der, said feeding means including an intermittentdrivin'g element, a vibratory lever actuated by said rotary shaft, means connecting said vibratory lever with said intermittent driving element, and a fulcrumstud providing an eccentricany located pivot for said vibratory lever, said fulcrum-stud being mounted for turning movement thereby to shift the pivot of said vibratory lever to change the effective length of the same.

7. A sewing machine having stitch-forming mechanism and a work-holder which are relatively movable to space the stitches, a rotary shaft, an adjustable eccentric carried by said rotary shaft,

and feeding means for effecting progressive rela' ill Ill

as iaavc '4 chines comprising, a work-clamping member, a rotary shaft, an actuator carried by*s'aidsha ft,

a vibratory lever having a follower portion embracingsaid actuator, a shiftable fulcrum for said lever for varying its amplitude of vibration, and means to transmit work-feeding movement of said lever to said-work-clamping member;-

9. Work-feeding mechanism for sewing machines, comprising, awork-clamping -member-, 'a'

rotary shaft, an actuator carried by said shaftfa vibratory lever pivotally supported at one end and bifurcated at its other end to embrace said actuator, a shiftable fulcrum supporting said vibratory lever for varying its amplitude of vibration, and means to transmit work-feetiingmovement of said lever to said w'ork-clamping 'mem- -10 In a sewing machine of the buttonholetype, the combination with stitch-forming mechanismgand' a work holder which are relatively movable to space the stitches abouta buttonhole of a first feeding mechanism-to relatively-move the stitch-forming'mechanism and work-holder progressively in sewing about a portion of the buttonhole, a second feeding mechanism to relatively movethe stitch-forming mechanismandwork-holder progressively in sewing about an other portion of the buttonhole, and manually controlled means for rendering said second feeding-mechanism-effective during the whole or' any portion of the cycle of stitches made aroundthe' other portion of the buttonhole, saidsecond-'feed-* ing mechanism including a driving clutch ele ment, and-manually controlled'means forzren'r dering said clutch element effective during the whole-or any portion of the cycle of stitches made around the buttonhole-to drive I said; second feed-"' ingmechanism."- j 12;In abuttonhole sewing machinepthe combination ;with {stitch-formingmechanism "and work=holding-means movable relative tofieaclr other to'sew around a 'buttonhole; of ajpl'uralityf of separate feeding mechanisms'successivelyrem dered eifectiveforf Y producing a progressive 'rela--" tive shift between'said stitch-forming mechanism" and said Work-holding means during theform a-r tion'of the stitches around "the buttonholejanfdj means for selectively changing the 'peri odf of' duration 'of the "effective action of oneoffsaid': feeding mechanisms.v i iii "i 13. In a buttonhole sewing machinatheicoin f bination with stitch-forming jihchan snnfaiia work-holding means movable relative} -eaehother to sew around-1 a-buttonhole, ofarplurality of separate feeding "mechanisms successively rendered effective for producing'ifa progressive relative 'shift' between said stitchforming nrechanism and said work-holdingmeans "during -th'eformation of the stitches around the b'iittfcfnihole," an intermittentclutch-include'd'in oiie o feeding mechanismsa plurality bf cams, means controlled by a" 's'eiaa'aijon'ev of, salutes-ms; tori rendering said intrfriittentcliitch efictive', and

manually shiftable means for rendering any one of said cams efiective.

14. In a sewing machine of the buttonhole type, in combination, stitch-forming mechanism and a work-holder which are relatively movable to space the stitches about a buttonhole, a feedcam for effecting a relative movement between said stitch-forming mechanism and said workholder, means including an intermittent driving member for rotating said feed-cam, means operable to render said driving member effective, and means for selectively changing the period of duration of the eifective action of said driving member.

15. In a sewing machine of the buttonhole type, in combination, stitch-forming mechanism and a work-holder which are relatively movable to space the stitches about a buttonhole, a feedcam for efiecting a relative movement between said stitch-forming mechanism and said workholder, means including an intermittent driving member for rotating said feed-cam, a plurality of cams, means controlled by a selected one of said cams for rendering said intermittent driving member effective, said last named means including a lever provided with a roller, and means for shifting said roller into cooperative relation with a selected one of said cams.

16. In a sewing machine of the buttonhole type, in combination, stitch-forming mechanism and a work-holder which are relatively movable to space the stitches about a buttonhole, a feedcam for efiecting a relative movement between said stitch-forming mechanism and said workholder, means including a one-way acting clutch for rotating said feed-cam, said clutch having an outer clutch surface, an inner clutch surface, and a plurality of clutch-elements interposed between said outer and inner clutch surfaces, a clutch-element-releasing lever for each of said clutch-elements, a release-cam normally maintaining said clutch-element-releasing levers in positions such that the clutch-elements are held out of wedging position between said inner and outer clutch surfaces, a plurality of cams, a lever cooperating with a selected one of said cams for shifting said release-cam out of engagement with said clutch-element-releasing levers so that said clutch-elements can move into wedging position, and means for shifting said lever into cooperative relation with a selected one of said cams.

1'7. In a sewing machine of the buttonhole type, in combination, stitch-forming mechanism and a work-holder which are relatively movable to space the stitches about a buttonhole, a feedcam for efiecting a relative movement between said stitch-forming mechanism and said workholder, means including a one-way acting clutch for rotating said feed-cam, said clutch having an outer clutch surface an inner clutch surface, and

a plurality of clutch-elements interposed between said outer and inner clutch surfaces, a clutchelement-releasing lever for each of said clutchelements, a release-cam spring-biased into a position to normally maintain said clutch-elementreleasing levers in positions such that the clutchelements are held out of wedging position between said inner and outer clutch surfaces, and manually controlled means operable at will for shifting said release-cam to a position out of engagement with said clutch-element-releasin levers so that said clutch-elements can move into wedging position.

EDWARD P. SPAINE.

HAROLD C. FAULKNER.

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