US3316868A - Buttonhole stitching device - Google Patents

Description

May 2, 1967 YASUKATA EGUCHI 3,316,868

BUTTONHOLE STITCHING DEVICE Filed Feb. 2, 1960 7 Sheets-Sheet l INVENTpgz.

/uzzM47 May 2, l967 YASUKATA EGUcHi 3,316,868

BUTTONHOLE STITCHING DEVICE 7 Sheets-Sheet 2 Filed Feb. 2, 1960 INVENToR.

May 2, 1957 YASUKATA x-:GUcl-n 3,316,868

BUTTONHOLE STITCHING DEVICE F1' led Feb, 2, 1960 7 Sheets-Sheet l5 IIE 55 #EYE-5A we, m- 6 femm! h WD; fac aN/C ff/f i 9 7 E @Ugg/9c INVENTOR.

May 2, l937 YASUKATA EGUCHI BUTTONHOLE STITCHING DEVICE '7 Sheets-Sheet 4 Filed Feb. 2. 1960 INVEN'TOR..

ILM/Lad f. /zff/ebL May 2, 1967 l YASUKATA EGUCHI 3,316,868

BUTTONHOLE STITCHING DEVICE Filed Feb. 2. 1960 '7 Sheets-5heet 5 INVENTOR.

May 2, 1967 YASUKATA EGUCHI 3,316,868

BUTTONHOLE STITCHING DEVICE Filed F'eb. 2, 1960 7 Sheets-Sheet 6 1N V EN TOR.

May 2, 1967 INVENTOR. fas-@471 Ejmq BY "AMM f fsw@ n?. uw

United States Patent O 3,316,868 BUTTONHOLE STITCHING DEVICE Yasukata Eguchi, Tokyo, Japan, assigner to Janome Sewing Machine Co., Ltd., Tokyo, Japan Filed Feb. 2, 1960, Ser. No. 6,313

Claims priority, application Japan, Feb. 2, 1959,

:i4/4,922; Feb. 4, 1959, 34/ 3,532; Mar. 16, 1959,

9 Claims. (Cl. 112-158) This invention relates generally to improvements in a buttonhole stitching device for a zig-zag stitch sewing machine. The invention also relates to a composite cam for controlling the stitching of buttonholes by the sewing machine.

The primary object of the invention isa novel buttonhole stitching arrangement, of simple and sturdy design, but highly ecient in its operation and having a long span of life.

Another object of the invention is to provide a zig-zag stitch sewing machine, wherein a novel composite cam is attached onto the` regular pattern stitch cam shaft to cooperate with the regular cam follower, thereby providing a fast buttonhole-stitch-making operation.

Another object of the invention is to provide a zigzag stitch sewing machine wherein buttonhole stitches may be produced by manipulating the regular cam-selecting lever so `as to engage the normal cam follower with the novel composite cam.

Another object of the invention is to provide a zigzag stitch sewing machine of the kind above referred to, .'wherein the reverse feed necessary in the course of producing buttonhole stitches, is accomplished in a simple and rapid manner.

Another object of the invention is to provide a zig-zag sewing machine, which is provided with an eilicient and novel needle-bar-rocking motion mechanism, which cooperates with the above mentioned buttonholer mechani-sm.

Still another object of the invention is to provide a novel amplitude limiting device within the sewing machine and cooperating with the above mentioned buttonholer.

Various further and more specific objects, features and advantages of the invention will appear from the description given below, taken in connection with the accompanying drawings illustrating by way of example several preferred embodiments of this invention.

In the drawing:

FIGURE 1 is a front perspective view of an embodiment ofthe zig-zag stitch sewing machine embodying the principles of the invention;

FIGURE 2 is a plan view of the right-hand part of the machine shown in FIGURE 1, the upper cover being, however, removed to show the inside mechanisms more clearly, with part of the machine broken away for the same purpose;

FIGURE 3 is a cross-section of the machine arm taken on the line III-III in FIGURE 2;

FIGURE 4 is an enlarged front view of part of the machine, especially showing the cam selector lever and the reverse feed lever;

FIGURE 5A is an end view of the novel composite cam employed in the machine according to this invention;

FIGURE 5B is a sectional view of the composite cam taken in the axial direction;

FIGURE 6 is a diagrammatic representation of stitches along one buttonhole;

FIGURE 7 is a perspective view of part of stitch-control mechanism;

FIGURE S is a plan view of the left-hand part of the machine shown in FIGURE 1, the upper and end covers` being, however, removed to show the inside mechanisms more clearly;

3,316,868 Patented May 2, 1967 FIGURE 9 is a perspective view of the needle-bar assembly;

FIGURE 10 is a cross-section of part of the upper cover, especially illustrating the movable stop arrangement employed in a second embodiment of the invention;

FIGURE ll is a perspective exploded view, showing several related parts shown in FIGURE 1l);

FIGURE 12 is a perspective view of a modified amplitude adjusting lever for the embodiment shown in FIG- URE 10;

FIGURE 13 is a front perspective View of the second embodiment of the sewing machine according to the i11- vention, said machine includes several parts shown in FIGURES 10-12, inclusive; and

FIGURE 14 is a fragmentary perspective view on an enlarged scale illustrating a composite cam according to the invention.

Now referring to the drawings, especially FIGURE 2 thereof, a connecting link 1 is mounted at one end on a pivot 2, which is xed on a suitable part of the machine arm 50 by means of a set screw 4, while the said link iS pivotally connected at its other end through a pin 6 with a cam-selecting and shifting lever 5. A rocking shaft 8 is mounted on the machine and provided with a longitudinal key groove 10. A slide 7 is slidably mounted on the .shaft` 8, said slide having a key projection 9, which engages in the groove lil. The lever 5 is provided with a pin 11 fixed thereon, the free end of said pin 11 engaging in a lateral slot 7 formed on the slide 7. The lever 5 is further provided with an engaging pin 15, which is adapted to engage one of receiving wavy arresting recesses 12 formed on an arresting bar 12 at inner side thereof, said bar being xedly mounted at the front side of the machine arm by two set screws 13. A tension spring 17 is iixed at one end to the connecting link 1, while the other end of the spring is iixed to a stationary part of the machine, said spring urging the selecting and shifting lever 5 through the intermediary of link 1 to engage the pin 15 lwith one of said recesses 12'. The engaging pin 15 is formed with an indicating pointer 52, as shown in FIG- URES 3 and 4, said pointer cooperating with stitch indicia represented on an indicating plate 54, which is made of a suitable transparent material and covers a window 53 cut through the wall of machine arm 50, to show Iany selected stitch pattern to the operator.

The rocking shaft 8 is provided at its left-hand end, as viewed in FIGURE 2 with an operating or rocking arm 41 fixed thereon, with the guide surface 41' of said rocking arm kept in pressure contact with a contacting head 42 on one end of a connecting 4arm 43. For this pressure contact, a spring 71 (FIGURE 9) is provided on the needle-bar mechanism to bias the connecting arm 43.

In parallel with the rocking shaft i8, a cam shaft 3 is provided for driving a group of stitch cams 1-4 detachably lixed thereon. The cam shaft 3 is driven through a reduction gearing including bevel gears 58 and 59. A cam follower 18 is provided on the slide 7 and adapted to engage under pressure with any selected one of said cams 14. The aforementioned spring 7l (FIGURE 9) provided on the needle-bar mechanism acts through connecting rocking lever 43, rocking arm 41 and rockingshaft 8 upon the slide "7, to urge cam follower 1S into contact with one of the cams 14. The rocking lever 43 is provided with a pin 49 iixed on an intermediate portion thereof, said pin engaging the fork 48 formed on one arm 47 of an amplitude-limiting lever 46, which is pivotally mounted on a suitable portion of the machine arm 50 by means of a screw pin 45. Thus, when the lever 46 is manually rotated to the right, or to the left in FIG- URES 2 and 3, as the case may be, the contacting projection or head 42 formed on the connecting arm is correspondingly shifted in the downward or to the upward direction in FIG. 2, or to the right or to the left seen in FIG- URE 3, the head 42 being thus shifted as desired to a different position in contact with the guide surface 41.

It will be noted from the foregoing, that by manually shifting the cam-selecting lever in the longitudinal direction of the machine, against the action of the tension spring 17, the relative position of the cam follower 18 and the cam group 14 will be changed. The thus newly selected engaging position is maintained by the engagement of the arresting pin 15 with the corresponding suitable recesses 12 formed on the stop strip 12. It will be further clear, that under the above mentioned cam-andfollower engagement maintained at a suitably selected position, the lateral amplitude of the Zig-zag stitches can be properly adjusted or limited to any desired value by manually operating the lever 46 provided for this service. This kind of after-adjustment will -be more fully described hereinafter in connection with FIGURE 8.

An arrangement of buttonhole stitches, as shown diagrammatically and by way of example in FIGURE 6, is produced as will be described in detail hereinafter:

For this purpose, the cam shaft is provided with a specially designed composite cam 19 fixed thereon at one end of the regular stitch cam group 14. The configuration of the cam 19 can 'be clearly understood fr-om FIG- URES 5A and 5B of the drawings. The cam 19 is formed at its central periphery with a central Vcam track 1911 adapted to give a full-amplitude to the stitches produced under its control, while at both sides of said central cam Zone, two outer cam tracks 19a and 19e are formed von the cam 19, ladapted to give half-amplitude to the stitches produced under its control. T he highest portions of the half-amplitude cam track 19a have the same radial height and are positioned substantially aligned with the lowest points of the recesses of the opposite half-amplitude cam track 19C, while the lowest surfaces of the recesses of the cam track 19a have the same depth and are aligned with the lowest surfaces of the central cam track 19h. The highest surfaces of the latter have the same radial height and are positioned aligned with the extremities of the projections of the half-amplitude cam track 19C. Between the central cam track 19h and either side cam track 19a or 19C, there are provided at the Ihighest or the lowest portions inclined surfaces adapted to guide the cam follower 18 from one cam track to another. In order to provide for operative engagement of the cam follower 18 with the buttonhole stitch cam 19, the arresting bar 12 is provided at its opposite portion thereof to the cam 19 with a somewhat elongated engaging recess 12". When the cam-selecting lever 5 is manually shifted to the right-hand end of the strip 12 in FIG- URE 2, in order to bring the engaging pin 15 on the lever 5 into pressure-cont-act with the specially designed recess 12", the cam follower 18 will be thereby shifted correspondingly to the right-hand direction as seen in the same figure and brought into contact twith the cam 19. More specifically, with the cam follower 1S brought firstly in contact with the half-amplitude cam track 19a, the machine wi=ll operate with forward feed `with half-amplitude to sew a stitch zone from a to b, as shown in the left-hand side of FIGURE 6. When the needle has reached position b in FIGURE 6, the operator must push the lever 5 further to the right-hand direction in the same figure, in order to bring the cam follower 18 into pressure-contact with the centrally arranged, full-amplitude cam track 1%. Thus, it will be clear, -that the machine will produce, in this case, full-amplitude stitches as shown in the lower part of FIGURE 6, according to the central cam profile 191;. The pitch of the stitches can be, also in this case, modified at the operators will, by adjusting the feeding means, as Will be more fully described hereinafter. After the production of the full amplitude stitches illustrated in the lower part of FIGURE 6, half-amplitude stitches on the right side of the buttonhole must be made to a point denoted by a reference character c while the feed is reversed. For this purpose, a rotatable lateral shaft 2t) extends from the lower part of machine arm 50, as seen from FIGURE 2, to an oppositely arranged boss 36. A ring 38 is iixedly mounted on the shaft 20 by means of a set screw 39, in order to receive the axial thrust of the shaft 20, upon which the boss 21 of an operating arm- 21 is lixedly mounted by means of a set screw '37. At the tip of the arm 21, -an engaging pin 22 is rigidly attached thereto. As shown in FIG. 7, a vertical projection 21" extends upwardly from the boss 21', and an operating arm 24 is fixed to the projection 21 by means of set screws 23. Arm 24 is substantially vertical and the free upper end thereof is shaped in a curved portion 24', as clearly shown by the dotted lines in FIGURE 4. When the operator moves the selector lever 5 to the right-hand direction in FIGURES 1 and 2, to bring the lever into contact with the engageable end 24 yof operating arm 24 as shown in FIGURE 4 and pushes the lever 5 still further in the same direction, the operating arm 24 is caused to turn about the lateral shaft or pivot 20 in the clockwise direction seen in FIGURE 4, so that the engaging pin 22 tixedly mounted on the arm 21 is shifted in the downwardv direction.

There is provided in the present machine a feed adjuster 26 (see FIGURE 7). The feed adjuster is formed with a depending projection 27, on which is pivotally mounted a reverse feed lever 25 by means of a pivot 28. The lever 25 is formed with a push button 40 on its free end extending partly out of the machine for manual manipulation by the operator. The push button 40 carries thereon a mark R, which is an abbreviation of Reversing. Although not shown, a slide is slidably mounted in a groove 29 on the feed adjuster 26, and is operatively connected with a feed-adjusting member, not shown, which is in turn operatively connected with the lower driving shaft, again not shown, of the machine. 30 denotes a feed-adjusting, heart-shaped cam; 3-1 a feedadjusting screw connected with a feed-adjusting knob 32 extending partly out from the machine arm as shown in FIGURES l, 2 and 4; and 35 a tension spring extending from the machine arm to the feed adjuster 26. With the above arrangement, the machine can be adjusted at the operators will to feed the material in forward or rearward directions, as well as to modify the pitch of the stitches in a -well known manner. This feed reversing means does not constitute part of the present invention, so that for the simplification of the description, a detailed explanation thereof has been omitted herein.

In the present machine, however, the lever 25 is formed substantially at the center portion thereof with a vertical projection 25 which is formed at its one end with an outwardly inclined surface 25" which is adapted to contact with the tip of the aforementioned engaging pin 22. Thus, after the longer stitches at the end of the buttonhole shown in the lower part of FIGURE 6 have been successfully produced in the aforementioned manner, and the engaging pin 22 is shifted in the downward direction in FIGURE 4 by moving the selector lever 5 in the right-hand direction in the same figure, the pin 22 moves down along the inclined surface 25, to shift the reversing lever 25 inwardly, as if the operator had pushed the related button 46, so that the reversing stitches may ybe now produced. In this case, however, as the cam follower 13 is kept in pressure-contact with the outer half-amplitude cam Zone 19e, the reverse stitching will be completed up to the point c shown in FIGURE 6. At the arrival of the reverse stitching at the point c, the operator now shifts the selector lever 5 to the left as viewed in FIG- URES 1 and 4, in order to bring the cam followerr18 again into contact with the centrally arranged, fullamplitude cam zone 1912 to produce and finish the final longer lock stitches shown in the upper end of the buttonhole in FIGURE 6. It will be clear from the foregoing, that the completion of the last mentioned lock stitiches will thus complete the desired buttonhole stitching, as shown in FIGURE 6. When the operator lever 5 is moved again to the left to engage the cam follower with the half-amplitude cam zone 19a, new buttonhole stitches can be made.

The pitch` of the longer lock stitches at b and c, that is, the material feed in the case of the above-mentioned, full-amplitude stitch-making is produced while the cam lfollower 18 is kept in contact with the central cam zone 1919 on the composite cam 19, with the material feed being set to the neutral or O-position. The aforementioned set screws 23 serve to modify the relative relation between operating arm 24 and projection 21, or that between engaging pin and the inclined surface 25" to a suitable degree. The buttonhole stitches should also be made after such a correct adjustment. On the other hand, when the finest pitch of stitches, such as those for a buttonhole, is required, the adjustment of the neutral or O-position is highly important. In order to serve for this purpose, an eccentric sleeve 34 is normally xed in a boss 33 formed integrally to the machine arm 50, by means of a set screw, The feedadjust screw 31 is movably received in the eccentric sleeve 34, so that by modifying the angular setting thereof, the desired adjustment for O-position may be easily carried out.

Although not shown, motion is transmitted from the screw 31 through a pinion-and-rack mechanism to a pointer 131, which moves relative to an indicating transparent cover shown in FIGURES l and 4. Thus, the turning degree of knob 32, or the selected degree of feed can be easily seen by the operator at a glance.

In FIGURE l, left, a similar transparent cover 55 and a pointer 132 cooperating therewith are provided for indication of the angular displacement of the amplitudeadjusting lever 46.

Next, referring to FIGURES 8 and 9, the needle-bar operating mechanism will lbe described more in detail hereinbelow:

In the present machine, 4the needle-bar support 61 is provided with two needle-holding portions 62 and 63, made integrally therewith and receiving rigidly, but detachably, the needle bar 65, in the conventional manner. The needle bar support 61 is formed at its upper end withf an olfset vertical web 64', from which extends horizontally a flange-shaped base 64, while the machine arm 50 is provided with a stationary supporting member 66 lixed at a suitable place thereof, which member 66 pivotally receives said vertical web 64 at its receiving recess 66 through the intermediary of a pivot shaft 68, the latter being fixed in said supporting member 66 by means of a set screw 67. A pivot pin 69 is formed integrally with said flange-shaped base 64 and extends therefrom in the upward direction. A pivot arm 7) is provided with a sleeve-like projection made integrally therewith, said flange-shaped `base 64 `and said pivot arm 70 `being rotatably mounted on said pivot pin 69.

As already mentioned, the rocking arm 41 is fixed on the rocking shaft 8 at its left-hand end as seen in FIGURE 3, the bottom surface of said arm 41 being planar and engaged by the contacting head 42 provided on the rocking lever 43. The rocking lever 43 is provided at an intermediate position thereof with a pin 49 fixed thereon, and the pin engages in the forked end 48 on one integral arm of the amplitude-adjusting lever 46. The cam shaft 3 is driven at a reduced rate from the conventional main shaft 56 through a reduction gearing, of which only two bevel gears 58 and 59 are seen in FIGURE A2. The amplitude-adjusting lever 46 is mounted on a stationary portion 133 fixed onto the machine arm S0 by the screw stud 4S and through the intermediary of an elastic washer 134.

When the main shaft 56 runs, the cam shaft 3 is rotated thereby at a reduced rate through the intermediary of the aforementioned reduction gearing. Now, assuming that in this case, the cam follower 18 is kept in pressure contact with -any selected one of the yregular stitch pattern cams 14 as shown in FIGURES 1, 3 and 8, the follower will make tip-and-down motion according to the peripheral conguration of rthe thus selected pattern cam. The rocker shaft 8, and -thus the operating or rocking arm 41 fixed thereto will make the corresponding rocking motion, which is transmitted through the contacting head 42 to the free or right-hand end of the connecting arm 43, whereby the needle-bar 65, urged in one direction by the attached 'tension spring 71, is caused to make lateral rocking motion about the horizontal pivot pin 68 in a vertical plane. It will thus be clear, that with the above men- -tioned arrangement the vertical rocking motion of the connecting arm 43 can Ibe successfully converted into thecorresponding lateral rocking motion of the needle-bar 65. In this case, when the amplitude-adjusting lever 46 is so adjusted that the attached pointer 132 is located at the indicia O on the viewing window cover SS, as seen from the FIGURE 1, and shifts pin 49 to `one extreme position -as at P in FIGURE 8, the amplitude will be reduced to nil. On the other hand, when the lever 46 is turned to the opposite extreme position corresponding to the mark 5 on the window cover 55, the pin 49 will be displaced to the opposite position Q, thereby the amplitude of the stitches being increased to the allowable maximum value in this oase. It will ybe clear, that with in intermediate adjustment of the lever 46 will produce an intermediate amplitude of the stitches. In any case, the degree of amplitude of stitches can be clearly indicated at a glance directed to the indication by the indicator 132 cooperating with the indicating marks or graduations 0-5 cut on the transparent cover 55.

j The embodiment shown in FIGURES 10l3, shows a somewhat different arrangement -of amplitude-limiting means 'from that shown in the preceding embodiment. A control stop lever v81 is formed near its lower end with an enlarged portion 136, from which projects horizontally arranged, sector-shaped, supporting projections 82 on opposite sides, each of said projections being provided with contacting edges 82', clearly shown in FIGURE lil. The supporting projections 82 of the -control stop lever 81 are pivotally mounted in corresponding bearing recesses 85 formed in a depending enlarged portion 84 on the bottom surface lof the clapper cover 83.

In order to allow the pivotal movement of the control stop lever 81, a relatively narrow opening 94 is lcut through the wall of the aforementioned portion 84, in the manner to define one side of each bearing recess ,85, as

most clearly shown in FIGURE l1, below the showing of a part of upper cover 83 in its inverted state. A snap spring in the form -of `plate spring 86 is formed therein with Iopen recess 9S extending from its one end Ito a suhstantial length thereof, to form a forked end 96, while it is formed therethrough with an opening 86a in the proximi-ty of 4the opposite end of said spring 86. When used, -the spring 86 is fixed at a proper position on the bottom surface of the upper cover 83 in the proximity of one end of the aforementioned vertical opening 94, as shown in FIGURE Il0, by tightening a 'fixing screw 87 passing through the opening 86a. The open recess 95 serves for guidance of the lower end portion of said. lever 81, and both tongues of the fork 96 are kept in pressure engagement with the aforementioned contacting surfaces 82 of supporting yprojections 82.

In FIGURE 12, reference numeral 108 represents a somewhat different embodiment of amplitude-adjusting lever from that shown iby reference numeral 46 in the preceding embodiment. This lever 108 is mounted pivotlally on a suitable part, not shown, of the machine arm 'by means of a pivot screw 109 and the operating end of the lever 108 projects outwardly from the machine through an elongated opening 123 cut through vthe upper cover 83, as clearly seen from FIGURE 13. The opposite or inner end of the lever 108 is pivoted by means Iof a pivot pm 110 t-o a connecting rod 111, which is in turn operatively connected with the needle-bar mechanism, not shown. The above mentioned arrangement is so designed, that when the lever 108 is positioned at its one extreme position as denoted by reference character R in AFIGURE 12, the amplitude of stitch will amount to O, while when the lever is maintained at the opposite extreme position T, the amplitude will be the largest indicated value 5. With the lever situated at 2.5, the amplitude will be half the above mentioned maximum amplitude. The indicated values (l1-5 can be easily seen from the numerical representations shown on a cover plate 121 substantially covering the opening 123. The present embodiment serves to hold the amplitude-adjusting lever 108 maintained accurately at its half-amplitude position, when the operator desires to do so.

When the operator moves a handle 112 attached to the stop lever 81 and extending outwardly of the upper cover 83, to the right or to the left in FIGURE l0, the control stop lever will be turned about the supporting projections. As already mentioned, the spring 86 acts with its forked ends 96 upon the contacting edges 82 of the projections S2, and the above mentioned rotational movement of lever 81 will be partially resisted, and partially accelerated by the spring force. Dimensions and arrangements of the above mentioned several parts are so selected, that when the lever 81 is turned under assistance of spring 86 to its right-hand extreme position in IFIGURE `10 to abut with its inside edge 120 against the upper right corner wall edge 94 of .the vertical opening 94, the lowermost projection 98 of lever 81 is brought into contact with the left side surface 99 yof the amplitudeadjusting lever 108 situated at the half-amplitude position S thereof, thus preventing the last mentioned lever from being further turned to increase the amplitude of zig-zag stitches. In other words, when it is desired to limit the amplitude t-o that equivalent to half the attainable maximum value at the time being, the handle is shifted to the right-hand extreme position in FIGURE l0, until the lever edge collides against the wall corner 94 and is kept thereat by the action of the snap spring 86. Then, the amplitado-adjusting lever 108 is turned to the left so that the left side surface 99 thereof is brought into and kept in contact with the lowermost projection 98 `of movable lever 81. Under these conditions, where Ithe amplitude of the stitches is thus reduced to the half, simultaneous working with two machine needles will cause none of the damages, which may otherwise be lia-ble to take place.

When the operator desires to restore the above mentioned arrangement from the half-amplitude condition, he must return at first the adjusting lever 108 to R-position as shown in full lines in FIGURE 12 yand then turn the movable lever S1 in the anti-clockwise direction in FIGURE l0, until it abuts with its opposite side edge 117 againstV the opposite wall corner 94', as shown by chain-dotted lines therein, thus withdrawing the lowermost projection 98 of lever 81 completely out of the path of the adjusting lever 108. rThus, under these conditions, the lever 108 may be freely shifted by the operator from the zero-amplitude position R to the maximum amplitude position T, or in the reverse order. The Zero-amplitude position of lever 108 is also shown in FIGURE 10 by chain-dotted lines attached with the same reference numeral.

It will be clear, that the above mentioned movable lever 81 can be applied to the amplitude-adjusting lever 46 with slight modifications. In order to show such a possibility, a similar movable lever 81a has been shown in FIG. 1 diagrammatically by phantom lines, nearly at the center between the balance wheel 135 and the removable end cover 100, the latter, however, has been shownV in FIGURE 8, only diagrammatic-ally by chaindotted line.

Although certain particular embodiments of the invention are herein disclosed for purposes of explanation,

further modifications, after study of this specification, will be apparent to those skilled in the art to which the invention pertains. Reference should accordingly be had to the appended claims in determining the scope of the invention.

What is claimed and desired to be secured by Letters Patent is:

1, In a sewing machine, in combination, a buttonhole stitching device comprising a rotary composite cam having two outer cam tracks and a central cam track formed with projections and recesses, said projections of` said outer cam tracks having the same height, and said projections of said central cam track having twice the height of said projections of said outer cam track, the extremities of said projections of one of said outer cam tracks and the lowest points of said recesses of the other of said outer cam tracks being aligned; means mounting said cam for rot-ation -about an axis; an oscillatable cam follower means movable along said axis between three inoperative positions respectively located opposite said cam tracks spaced from the same, and turnable from each of said inoperative positions to a corresponding operative position for cooperating with said three cam tracks, respectively; shifting means for selectively shifting said cam follower means between said inoperative positions, and from the same to said operative positions, respectively, so that said cam follower means is oscillated in said operative positions in accordance with said three cam track p-atterns, respectively; a needle bar assembly; connecting means operatively connecting said cam follower means with said needle bar assembly so that the same is transversely oscillated, said needle bar assembly producing smaller transverse stitches when said cam follower means cooperates with said outer cam tracks, and longer transverse stitches when said cam follower means cooperates with said central cam track, said smaller transverse stitches produced under control of said outer cam tracks, respectively, being in transversely spaced positions, and said longer stitches extending transversely over said smaller stitches; feed reversing means for reversing the feeding direction in which a material is fed to said needle bar assembly; and linkage means connecting said shifting means with said feed reversing means for reversing the feeding direction when said cam follower means is shifted from the position with either one of said outer cam tracks to the position cooperating with either one of said outer cam tracks to the position cooperating with the respective other cam track.

2. A sewing machine as set forth in claim 1 wherein said shifting means includes a rst manually operated lever; guide means extending parallel to said axis; a slide mounted on said guide means for movement along the same and connected to and operated by said manually operated lever, said slide supporting said cam follower means for movement between said three inoperative positions thereof, said shifting means including a second manually operated lever operatively connected with said cam follower means for moving the same between said inoperative land operative positions.

3. A sewing `machine as set forth in claim 2 wherein said linkage means include a linkage lever; land wherein said feed reversing means includes a control member having an inclined shoulder cooperating with said linkage lever; and wherein said first manually operated lever engages said linkage lever for shifting the same to a position in which said control member of said feed reversing means is shifted by engagement between saidV linkage lever and said inclined shoulder to reverse the feeding direction.

4. A sewing machine as set forth in claim 3 wherein said first linkage lever includes two portions, and means for securing said portions to each other in different adjusted positions.

5. A sewing machine as set forth in claim 1 wherein said connecting means include a rockable shaft supi porting said cam follower means; an arm secured to said rockable s-haft; a rockable lever secured to said `needle bar assembly for movement with the same and being engaged and operated by said arm; an amplitude adjusting means -operatively `connected to said rockable lever for displacing the same along said arm so that the effective length of the same and thereby the amplitude of the stitches is adjusted; and a manually operated control stop having a first position for blocking said amplitude adjusting means in a position in which the stitch amplitude is limited, and a releasing position permitting free adjustment of said amplitude adjusting means.

6. A sewing machine as set forth in claim 1 and including a set of rotary cams having `different cam track patterns, said set of cams and said composite cam having a common axis of rotation; said cam follower means being shiftable to further inoperative and operative positions respectively cooperating with said cams of said set of cams whereby said needle bar assembly produces different ornamental stitches; and an arresting bar having a plurality of arresting recesses for arresting said shifting means in positions in which said cam follower means cooperates with said cams of said set of cams, and having a longer recess permitting manual movement of said shifting means between said three inoperative positions in which said cam follower means is located opposite said three cam tracks of said composite cam, respectively.

7. In a sewing machine, in combination, a buttonhole stitching device, comprising, in combination, a cam having two rst cam tracks and one second cam track formed with projections and recesses, said projections of said second cam track having a greater height than said projections of said first cam tracks, the extremities of said projections of second cam track and of one of the first cam tracks being aligned, and the lowest points of said recesses of said second cam track and of the other first cam track being aligned; means mounting said cam for rotation about an axis an oscillatable cam follower means movable 'along said axis between three inoperative positions respectively located opposite said cam tracks spaced from the same, and turnable from each of said inoperative positions to a corresponding operative position for cooperating with said three cam tracks, respectively; operating means for selectively moving said cam follower means between said inoperative positions, and from the same to said -operative positions, respectively, so that said cam follower means performs in said operative position oscillations about spaced centers of oscillation when engaging said first cam tracks and performs oscillations of greater amplitude when engaging said second cam track about a center of oscillation located between said spaced centers; a needle bar assembly; and means for connecting said cam follower means to said needle ybar assembly so that the same is transversely oscillated un-der the control of said cam follower means, said needle bar assembly producing smaller transverse stitches in transversely spaced positions when said cam follower means cooperates with said outer cam tracks, and producing longer transverse stitches extending transversely over said smaller stitches when said cam follower means cooperates with said central cam track; feed reversing means for reversing the feeding direction in which a material is fed to said needle bar assembly; and means connecting said operating means with said feed reversing means for effecting feeding in opposite directions when said cam follower means is in the two positions cooperating with said outer cam tracks.

8. In a sewing machine, in combination, a buttonhole stitching device, comprising, in combination, a rotary composite cam having an axis of rotation and having on the periphery thereof two `first circumferential cam tracks and one third circumferential cam track, said cam tracks `being formed with radial projections and recesses,

said projections of said second cam track having a Igreater height than said projections of said iirst cam tracks, the extremities of said projections of said second cam track and of one of the first cam tracks having the same elfective radius, and the lowest points of said recesses of said second cam track and of the other first cam track having the same effective radius; an oscillatable cam follower means `shiftable lin axial direction between three inoperative positions located opposite said three cam tracks, respectively, and being turnable from said inoperative positions, respectively, to three operative positions cooperating with said cam tracks, respectively; first operating means for selectively moving said cam follower means between said inoperative positions; second operating means for moving said cam follower means between said inoperative and operative positions so that said cam follower means in said operative positions performs oscillations about radially spaced centers of oscillation when engaging said lirst cam tracks and performs oscillations of greater amplitude when engaging said second cam track about a center of oscillation located between said radially spaced centers; a needle bar assembly; and means for connecting said cam follower means to said needle bar assembly so that the same is transversely oscillated under the control o-f said cam follower means, said needle bar assembly producing smaller transverse stitches in transversely spaced positions when said cam follower means cooperates with said outer cam tracks, and producing longer transverse stitches extending transversely over said smaller stitches when s-aid cam follower means cooperates with said central cam track; feed reversing means for reversing the feeding direction in which a material is fed to said needle bar assembly; and means for connecting said operating means with said feed reversing means for affecting feeding in opposite directions only when said cam follower means is in the two positions cooperating with said outer cam tracks.

9. In a sewing machine, in combination, a `buttonhole stitching device, comprising, in combination, cam lfollower means; mounting means for mounting cam follower means for oscillation about an axis and for turning movement about said axis between three operative positions and three corresponding in operative positions respectively, and also for axial movement between said inoperative positions; first operating means for turning said cam follower means between said inoperative and operative positions; second operating means for axially moving said cam follower means between said inoperative positions; cam means having two iirst cam tracks and one third cam track respectively engageable with said cam follower means in said three operative positions of said cam follower means, said first cam tracks having projections and recesses for oscillating said cam follower means about two spaced centers of oscillations, respectively, and said second cam track having projections and recesses yfor oscillating said cam follower means about a center of oscillation located intermediate said centers of oscillations and at such an amplitude `as to overlap the oscillations of said cam follower means under control of said first cam tracks, said cam follower means being outwardly spaced from said iirst and second cam tracks in said three inoperative positions, respectively, so as to be axially movable lby said second operating means between said inoperative positions for selection of one of said cam tracks; a needle bar assembly; means for connecting said cam follower means to said needle bar assembly so that the same is transversely oscillated under the control of said cam follower means, said needle bar assembly producing transverse stitches in transversely spaced positions when said cam follower means co-operate with said first cam tracks, and producing transverse stitches overlapping with the stitches produced under control of said first cam tracks when said cam follower means cooperates with said second cam track; feed reversing means for reversing the feeding direction in which a material is fed to said needle bar assembly; and means for connecting said operating means with said feed reversing means for eectinlg feeding in opposite directions only when said cam follower means is in the two positions, respectively, in which said cam follower means cooperates with said rst cam tracks.

UNITED References Cited by the Examiner 2,888,893 6/1959 Gegauf 112-158 2,900,937 8/1959 Gegauf 112-158 FOREIGN PATENTS 792,784 4/1958 Great Britain.

552,428 12/1956 ltaly. 331,817 9/1958 Switzerland.

OTHER REFERENCES German application, N, 12158 VII/52a, Oct. 31, 1956.

JORDAN FRANKLIN, Primary Examiner. DAVTD J. WI'LLIAMOWSKY, Examiner.

H. D. COOPER, Assistant Examiner.

Claims (1)

1. IN A SEWING MACHINE, IN COMBINATION, A BUTTONHOLE STITCHING DEVICE COMPRISING A ROTARY COMPOSITE CAM HAVING TWO OUTER CAM TRACKS AND A CENTRAL CAM TRACK FORMED WITH PROJECTIONS AND RECESSES, SAID PROJECTIONS OF SAID OUTER CAM TRACKS HAVING THE SAME HEIGHT, AND SAID PROJECTIONS OF SAID CENTRAL CAM TRACK HAVING TWICE THE HEIGHT OF SAID PROJECTIONS OF SAID OUTER CAM TRACK, THE EXTREMITIES OF SAID PROJECTIONS OF ONE OF SAID OUTER CAM TRACKS AND THE LOWEST POINTS OF SAID RECESSES OF THE OTHER OF SAID OUTER CAM TRACKS BEING ALIGNED; MEANS MOUNTING SAID CAM FOR ROTATION ABOUT AN AXIS; AN OSCILLATABLE CAM FOLLOWER MEANS MOVABLE ALONG SAID AXIS BETWEEN THREE INOPERATIVE POSITIONS RESPECTIVELY LOCATED OPPOSITE SAID CAM TRACKS SPACED FROM THE SAME, AND TURNABLE FROM EACH OF SAID INOPERATIVE POSITIONS TO A CORRESPONDING OPERATIVE POSITION FOR COOPERATING WITH SAID THREE CAM TRACKS, RESPECTIVELY; SHIFTING MEANS FOR SELECTIVELY SHIFTING SAID CAM FOLLOWER MEANS BETWEEN SAID INOPERATIVE POSITIONS, AND FROM THE SAME TO SAID OPERATIVE POSITIONS, RESPECTIVELY, SO THAT SAID CAM FOLLOWER MEANS IS OSCILLATED IN SAID OPERATIVE POSITIONS IN ACCORDANCE WITH SAID THREE CAM TRACK PATTERNS, RESPECTIVELY; A NEEDLE

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