US1844426A - Buttonhole sewing machine - Google Patents

Description

Feb. 9, 1932. J. KIEWICZ BUTTONHOLE SEWING MACHINE 1928 6 Sheets-Sheet Filed April 14 AYE 4:2.

lnven'tov. dohn Kiew WWW w 7 Feb. 9, 1932. J. KlEWlCZ BUTTONHOLE SEWING MACHINE Filed April 14, 1928 s Sheets-Sheet 2 ATTys.

lnvenTor. John Kiewicg byWWJ W.

Feb. 9, 1932. J. KIEWICZ BUTTONHOLE SEWING MACHINE Filed April 14, 1928' 6 Sheets-Sheet 3 lnven'for. Uohn Kiewicg ATTys.

Feb. 9, 1932. J. KIEWICZ 1,844,426

BUTTONHOLE SEWING MACHINE Filed April 14, 1928 6 Sheets-Sheet 5 W W iVNHllll I n v e n To 1".

do h n K i aw i (:3 yMMkW ATTys.

Feb. 9, 1932.

J. KIEWICZ 1,844,426

BUTTONHOLE SEWING MACHINE Filed April 14, 1928 6 Sheets-Sheet 6 93? I03 F1 g. 16. e2 6 2| 4s l 32 as 2g /2 9 27 lnvenTor.

ll'! W, John Kiewic Any Patented F el). 9, 1932 UNITED STATES PATENT OFFICE JOHN KIEWIOZ, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE REECE BUTTON HOLE MACHINE COMPANY, 011 BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE BUTTONHOLE SEWING MACHINE Application filed April 14,

This invention relates to buttonhole sewing machines and pz'irtlcularly to means for trimming the thread and cutting the buttonholc slit atthe end of the sewing operation.

stay cord also. if one is used). 1

According to one feature of the invention the means for cutting one of the threads is *arried and operated by the buttonhole cutting inc hanism so that at the end of the buttonhole the operation of cutting the button hole also results in cutting one oi the threads.

The huttonhole sewing machine herein shown is of that type adapted to sew a. but tonhole with an eye and 111 which the stitchv il'orming mechanism mounted to rotate at each end of the huttonhole.

According to another feature of the invention the means for cutting the other thread is arranged to be actuated by the devices tor rotating the st' clrforming mechanism so that as the stitch-forming mechanism is turned at the end of the buttonhole the thread will at the same time he severed.

Another teature of the invention relates to novel means for holding the under thread utter it is cut and until the first stitches he e been made on the next succeeding buttonhole thereby ensuring the proper formation of the lirst stitches.

Other features of the invention relate to various improvements in buttonhole sewing machines all as will be more fully hereinafter forth.

ln order to give an uiulcrstanding oi the invention 1 have illustrated in the drawings a selected embodiment thereof which will now he described atter which the novel features will he pointed out in the appended claims.

l ig. l is a side view ot a sewing machine cmhmlyine' my invention;

l ig. 2 :1 plan view oi the work-supporting portion ot the lied with the clamp plates removed to show the part of the huttouhole cu": 11g mechanism and the cutter tor the upper thread; i

1928. Serial No. 269,985.

Fig. 3 is a section on the line 3--3 of Fig. 2;

Fig. 4 is an under side view of the bed showing the means for actuating the under thread cutter;

Fig. 5 is a front elevation of the head showing the pull-oil for the upper thread;

Fig. 6 is a fragmentary View illustrating the cutter for the under thread and stay cord;

Figs. 7 and 8 are views of two opposite sides of the turret and under thread mechanism;

Figs. 9 and 10 are views of the under thread mechanism illustrating the tension release for the under thread and the under thread gripping device;

Fig. 11 is a fragmentary plan view 01 the turret illustrating the means for actuating the under thread gripping device;

Fig. 12 is a section on the line 12-12, Fig. 9;

Fig. 13 is a f 'agmentary view showing the buttonhole cutters in operative position;

Fig. 14 is a plan view similar to Fig. 2 but illustrating the turret in the position it occupies at the end of the buttonhole;

Fig. 15 is a section on the line 1515,

16 is a section 011 the line 1G16, Fig. 14;

Fig. 17 is a fragmentary view showing the operation of the pull-oil for the upper thread.

In the drawings 1 indicates the frame of the sewing machine which carries the stitchforming mechanism, the latter comprising the upper needle 2 mounted in the verticallyreciprocating needle bar 3 and operating from above the work, and under-thread mechanism, indicated generally at 4, and sit uated beneath the work.

The frame 1 is mounted on the bed 81 which carries the work clamps. 46 by which the other of which is a cutting block.

fact that the frame 1 is allowed to move back and forth on the bed 31.

As stated above, the sewing machine herein shown is of that type in which the stitchforming mechanism is mounted to rotate at each end of the buttonhole and for this purpose the under thread mechanism 4 is mounted on the usual turret 5 which carries at its upper end the throat plate 6 having the sewing opening 7 through which the upper needle operates, said turret being mounted to rotate in suitable bearings 8. The needle bar 3 with the needle 2 is also mounted to rotate and the means herein shown for giving the turret and the needle bar their rotation'almovements at each end of the buttonhole is such as is commonly employed in buttonhole sewing machines.

This rotational movement is secured from a vertically-arranged rock shaft 9 journalled in the frame and carrying. at its upper end a segmental gear 10 meshing with a gearing 11 by which the needle bar is; turned, said shaft carrying at its lower end another segmental gear 12 which meshes with a gear 13 on the turret 5. The turning movement of the rock shaft 9 is secured at proper times from the main cam 14 which is mounted in the usual cam casing 15 that is secured to the frame 1. The rock shaft 9 has the arm 16 rigid therewith which is connected by a link 17 to the end of a lever 18 pivoted to the cam housing at 19, said lever being given a vibrating movement from full to dotted line position Fig. 4 through the medium of a cam groove. (not shown) formed in the main cam 14. This means for rotating the stitch-forming mechanism is such as is commonly employed in buttonhole sewing machines.

The machine herein shown is also provided with buttonhole cutting mechanism for cutting the buttonhole slit. This cutting mechanism comprises two cutting elements 20 and 21, one of which is a cutting blade ind he element 20 is shown as mounted on a lever 22 pivoted to the frame at 23 and having at its rear end a follower 24 adapted to be engaged by a cam projection 25 on the main cam 14, said cam projection being so disposed that at the proper time in the sewing cycle the lever 22 will be actuated to bring the cutting element 20 into operative position. The other cutting element 21 is movably mounted, it normally being inits retracted position shown in Fig. 1 during the sewing on the button hole but being moved forward into'its operative position shown in Fig. 13 at the time that i the lever 22 is actuated.-

Either cutting element maybe the cutting blade and the other the cutting block. In the construction shown the member 20 is in the form of a block and the member 21 has the cutting edge but so far as the invention is concerned the member 20 may have the cutting edge and the member 21 might be in the form of a block.

The cutting member 21 is carried by a block 26 which is adjustably carried by a slide 27 that slides back and forth in ways 28 formed on the cam casing 15. The block 26 is retained in its adjusted position on the slide 27 through the mediumof clamping screws 29.

As stated above the cutting element 21 and the block26 on which it is mounted are normally inretracted position shown in Figs. 1 and 2 but they are'move'd forward into the operative position shown in Figs. 13 and 9 by the operative movement of the lever 22.

This isaccomplished by the following mechanism. Slidably mounted in bearings 30 carried by the stationary bed31 of the, ma-

chine is a controlling rod 32, the latter having an arm 33 fast thereto, the end 34 of which' extends into an opening formed in the side of the block 26. This rod 32 is provided with a notch in which is received the lower end of a lever 36, the latter being pivoted at 37 to a bracket 38 on the frame 1., This lever is provided with a cam surface 39 adapted to be engaged by a roller 40 on the end of a lever 41 pivoted at 42 to the frame, said lever having at its rear end a lateral projection 43 adapted to be engaged by the rear end of the lever 22. The lever 41 is acted on by a spring'44 which tends to hold it in the position shown inFig. 1 and the lever 36 is acted on by a return spring 45.

When the lever 22 is actuated to bring the cutting element 20 into operative position the upward movement ofthe rear end of the lever will rock the lever 41 thereby causing the roll 40 to engage the cam surface 39 andswing the lever 36 forwardly into the position shown in Fig. 13. Such movement of the lever will carry therod 32 forwardly thereby moving the slide27 forwardly and placing the cutting element 21 into its operative position shown in Fig. 13. Hence. as the cutting element 20 moves downwardlythe cooperating element 21 will move forwardly into position beneath the element 20 and the two elements will serve to out the buttonhole slit in the work which is then held in place by the work clamps 46.

One feature of my present invention relates to means associated with the buttonhole cutting mechanism for cutting the upper thread at the endof the sewing operation. As usual, in buttonhole sewing machines the stitch-forming mechanism is so constructed that when the machine comes to rest with with the cutting element 21 for cutting the leg of the loop l? as the buttonhole slit cut. This is accomplished. by a cutter 49 that is carried by the block 26 and is situated in front of the cutting element 21. This cut ting blade i9 is so disposed that when the cutting element 21 moves forwardly into its opeiatiw position as shown in Figs. 9 and 13 said cutting blade ill will pass underneath the threat 6. This blade is formed with the hook portion 50 having its front edge 51 curved and its rear edge 52 formed as a cutting edge.

During the movement of the cutter 49 into the position shown in Figs. 9 and 13 the leg .-l8 of the loop ll" will engage the curved face 51 and will be deflected thereby behind the book 50 as shown in Fig. 13 so that during the buttonhole cutting operation the leg l8 of the loop 4? is located in the rear of the hook 00. hen the cutting of the buttonhole is con'lpleted and the follower 24- passes oil from the cam 25 the springs rel and l5 will return the slide 27 and cutting element El to their nor ial retracted position, this return movement being a rapid one. During the return movement the cutting edge 52 will sever the leg l8 of the loop e7 directly be neath the throat (3. The cutting of the upper thread, therefore, is tlCCOlTlPllSllQCl by means associated with the buttonhole cutting mechanism.

l have also provided herein means for en gaging the upper thread and pulling the cut loop l7 bac through the work so as to leave a sufficient length of thread projecting from the eye of the needle 2 to permit of the pro per formation of the first stitch on the next lnittonholc. This pulling out of the loop is accomplished by a pull-oil lever 53 (see Figs. 1, and 17) which is pivoted to the frame 1 at 54. The end of the pull-off lever is formed with a thread-retaining notch During the sewing on the buttonhole said lever is in the full line position Fig. 5, it being retained therein by means of a spring 156. As the but tonhole is cut the lever is swung into the dotted line position Fig. 5 during which movement the notched end wipes by the length of upper thread t, said lever being so arranged that when it is in the dotted line position said thread in line with the notch Jitter the buttonhole is cut the lever 53 is swun back into the full line position during which movement the thread 2? is engaged by the notch 55 and the movement of the pulloil' nulls the cut loop out through the work.

For thus operating the pull-oil device the in or is provided with a finger 56 which ituated above the inclined pull-off arm as hown in YVhen the lever makes its operative movement this finger 56 will engage the lever 53 and will swing it back into the dotted line position and as soon as the bnttonhole has been cut and the arm 22 is rel in turned to its raised position the spring 156 will return the pull-off arm 53 to its operative posit-ion thus pulling off the cut loop of upper thread.

F or cutting the under thread, as well as stay cord, if one is used, I propose to employ a cutter 57 which is carried by a rock shaft 58 journalled in one of the clamp plates 59, said cutter having the cutting edge 60. This thread cutter is simiar to thread cutters which have heretofore been used for cutting the under thread and it is in the form of a plate operating directly above the clamp plates and thus lying underneath the work.

l/Vhen the sewing on the buttonhole has been completed the cutter 57 is swung from the full to the dotted line position Fig. 6 thus carrying the cutting edge 60 across the sewing opening of the throat 6 which at this time in the sewing circle is located in the position shown in Fig. 6. This cutting movement of the thread cutter 57 will sever the under thread close to the work and bet-ween the latter and the throat and will also cut the stay cord, if one is used.

In the present embodiment of my invention the ope 'ative movement of the thread cutter 57 is derived from the means for rotating the stitch-forming mechanism.

It will be understood by those skilled in the art that after the sewing on the buttonhole has been completed the stitch-forming mechanism is driven a half rotation to return it to proper position to begin the sewing on the next buttonhole and it is during this rotation of the stitch-forming mechanism that the cutter 57 is operated.

The rock shaft 58 has fast thereto an arm 61 which is adapted to be engaged by a projection 62 carried by a slide 63. This slide 63 is guided at one endby a guidii'ig pin 64: which is mounted on the under side of the bed 31 and extends through a slot 65 in the slide, the other end of the slide being pivotally con nected to a lever 66 which is pivoted to the bed at 67. This lever has at its rear end a latch member 68 adapted to be engaged by a projection 69 forn'ied on the link 17. The lever (36 is acted on by a return spring 70 which normally holds it in the position shown in Fig. at.

The sewing machine herein shown is of that type in which the frame 1 moves back and forth on the bed 31 during the stitching along the sides of the buttonhole, said frame and cam casing moving from the full to the dotted line position, Fig. 4-. when sewing down the first side of the buttonhole and then returning to the full line position when sewing the second side of the buttonhole. lVhen the sewing on the buttonhole has been. con1- pleted the parts are in the full line position Fig. l with the projection 69 behind the latch 68. At this time the main cam 14 moves the lever 18 from the full to the dotted to the dotted line position the projection 69 will be carried out of engagement with the latch 68 thusallowing th-elever 66 to hereturned to its initial position by the spring 70. The cutter 57 is-"also returned to its initial position by a spring 71.? The cutting of the under thread and stay cord also if one is used, is thus accomplished by the means which gives the turret its rotation at the end of the buttonhole.

I have also provided novel means for gripping the under thread a after it is cut and holding the cut end'unt-il after the first few stitches have been completed on the next buttonhole, and l have further provided means co-operating with the thread-gripping device to pull off a length of under thread after the latter has been gripped thereby to provide sufficient slack thread to enable the first stitches to be properly formed.

The under thread a extendsfrom the source of supply through a suitable guiding tube 7 2 carried by the turret, thence through the under thread tension 73 comprising the usual tension disks 74,775 between which the thread passes and which are held in frictional con 7 tact with the thread by the spring 76, thence Fig. 10 thereby releasing the under thread.

through a. guide eye 77 at the end of aresilient pull-oil arm 7 8, thence through another guiding tube 7 9 to one of the loopers of the under thread mechanism and from the looper through an opening 80 in the throat 6 which leads to the sewing opening thereof, this being the usual way of threading up under thread mechanism of this type.

The means for gripping the under thread a at the end of the sewing operation comprises a gripping finger 81 which cooperates with a shoulder 82 formed on the throat 6 adjacent the opening 80, said shoulder being so disposed that thethread passes over the shoulder as it is led through the throat 6. This thread-gripping finger 81 is normally separated from the shoulder 82 as shown in Fig.

10 but at the end of the sewing operation it is, moved into engagement with the shoulder asshown in Fig. 9 thereby gripping theunder thread a. and it remains in this operative position until the sewing has started on the next succeeding buttonhole., at which time it is returned to its inoperative position shown in This finger 81 is carried by a bar 83 which the "turret; This bar has a leaf-spring 85 secured thereto which bears against the turret and which normally tends to swing the thread-clamping arm into its operative position. 1

As stated above said arm is held in its inoperative position during the sewing of the buttonhole. The means for accomplishing this in the construction herein shown comprises a slide 86 carried in a suitable guide 87 mounted on the turret and having a projection 88 provided with a cam face 89. When the slide 86 is in the position shown in dotted lines FigLl the projection 88 occupies an opening 90in the thread-gripping finger 81 and at this time the spring 85 will hold the gripper inits operative position. If the slide 86 is moved into the position shown in Fig. 11 then the cam face 89 of the projection 88 engages the inclined face 91 at the end of the opening 90 with the result that the finger 81 is cammed or forcedbackwardly into its inoperative position. The movement ofthe slide 86 is suflicient so-that the projection 88 can be carriedbehind said finger and thus when the parts are in the position shown in Fig. 11 the gripping finger is held in its inoperative position by the projection 88. This is the position which the parts assume during the sewing on-the buttonhole.

- I have provided herein means operative when the sewing on the buttonhole is completed to'move the slide to the left Fig. 11, or to the right Fig. 14:, thereby releasing the gripping 'finger'and allowing it to move into gripping engagement with the under thread a.

It will be remembered that the turret 5.

on which the slide 86 is mounted, has a half revolution at each end Y of the buttonhole. During the stitching on the first side of the buttonhole the turret is in the position shown in Fig. 2 and the frame 1 with the turret is moving backwardly or toward the top of Fig.2. When the first side of the buttonhole has been'sewed the turret is given a half rotation to sew around the'eye of the buttonhole and then during the sewing of the second side-of the buttonhole the frame v1 on whichthe turret is mounted is moved forwardly thus bringing the turret into the position shown in Fig. 14:. As the buttonhole is completed the end 92 of the slide 86 i situated opposite the end 93 of a lever 94 which is pivotedat 95 to the bed plate and means are provided which become operative at the completion of the buttonhole to swing the lever 94 therebycausing it to shift the slide 86 into a position to release the thread gripping fingerSl therebyf allowing said finger to clampthe under thread it against 3 the shoulder 82. This operative movement is given to the lever 94 through the medium of the rod 32 which, it will be remembered, is

the rod that moves the cutting element 21 into its operative position.

The lever 94 is shown as having a cam face and the rod 32 is provided with a collar 07 situated to engage the cam face when the rod given its operative movement. Hence W 'hen the buttonhole cutter is actuated to cut the buttonhole the lever 94 will be turned into the dotted line position Fig. 14 by the collar 97 and such movement of the lever 04 will shift the slide 86 and thus render the under-thread gripping linger 81 operative.

Simultaneously with the gripping of the under thread by the finger 81 a length of r under thread will be drawn through the tension 73. This is provided for by the action of the pull-oil arm 7 8 together with the r lc: ing of the frictional pressure of the tension. 73 on the under thread.

The arm 78 is made of light spring and during the sewing operation the tension on the under thread a will be sufiicient so that the arm will be in the dotted line position Fig. 8. If the tension '73 is released, however, the resiliency of the arm 7 8 will cause it to move into the full line position Fig. 8 thus drawing a length of thread through the tension, it being remembered that the under thread held by the gripping finger 81.

Means are provided for releasing the tension 73 simultaneously *ith the gripping of the under thread by the finger 81. To accomggilnh this the bar 83 is provided with a depending linger 98 which acts against one end of lever 99 pivoted to the turret at 100, the other end of said lever acting against one end of a thrust pin 101 which finds a bearing in the turret, said thrust pin 1n turn acting against a follower 102 against which the tension spring 76 bears.

Under normal operation the disk 102 rests against the tension disk 74 so that the pressure of the spring 76 is applied to the tension d ish, this being the position of the parts when the clamping finger 81 is in its inoperative position shown in Fig. 10. When said clamping finger is moved into its operative position, however, the depending arm 98 rec the lever 99 thus n'ioving the thrust pin 101 into the position shown in Fig. 12 and thereby taking the spring tension off from the tension disks. As soon as this tension is relieved the resiliency of the pull-off arm causes it to move into the full line position Fig. 8 thus drawing off a length of under thread as above described.

It will thus be seen that the tension 73 and the thread-gripping arm 81 operate in opposition, the tension being operative when the threed-gripping arm is in inoperative position, as shown in Figs. and 11, and the tension being inoperative when the thread-gripping arm is in operative in Figs. 9 and 12.

I have described above how the threadposition, as. shown gripping finger 81 is brought into its operative position shown in Figs. 2 and 9 at the end of the sewing operation. Said finger remains in this operative position until after the stitching has begun on the next buttonhole at which time the finger is again thrown into its inoperative position by shifting the slide 86 into the position shown in Fig. 11.

For accomplishing this I have provided the following mechanism. Pivotally mounted on the turret bearing at 103 is a lever 104 which is acted upon by a suitable spring 105, said spring normally holding the lever against the stop 106. The slide 86 is formed at its end 92 with the ear 107. It will be remembered that the turret is in the position shown in Fig. 2 during the sewing on the first side of the buttonhole and that it makes a half rotation into the position shown in Fig. 14 in sewing around the eye of the buttonhole so that at the completion of the buttonhole it is in the position shown in said Fig. 14. Be fore the sewing begins on the next buttonhole the turret is given a reverse half rotation to bring it back into the position shown in Fig. 2 and as the turret completes its reverse half rotation the ear 107 is carried around the end 108 of the lever 104 as shown in Fig. 2. During the formation of the first stitches on the button hole the lever 104 is swung from the posit-ion shown in Fig. 2 to that shown in Fig. 11, such swinging movement causing the end 108 to engage the lug 107 and thus give the slide 86 its operative movement. This movement of the lever 104 is secured from. a pin 109 mounted in a bracket 110 secured to the bed 31 of the machine.

It will be remembered that during the sewing on the buttonhole the frame 1 with the turret is moving backwardly or toward the top of the sheet in Figs. 2 and 11. The pin 109, however, is carried by the stationary bracket 110 and hence as the frame 1 begins its feeding movement the cam face 111 on the lever 104 engages the pin 109 and thereby causes the lever to have its operative movement as shown in Fig. 11. The feeding movement of the frame 1 is sufiicient so that the end of the lever 104 is carried beyond the pin 109 and as soon as this occurs the spring 105 will restore the lever to the position shown in Fig. 2. The slide 86, however, will remain in its operative position until it has been re stored to the dotted line position shown in Fig. 14 by the-lever 94, as above described.

The pin 109 is yieldingly mounted as shown in Fig. 3, it being supported in a sleeve 112 and backed by a spring 113. The under face ot the end of the lever 104 is bevelled as shown at 114. WVhen the first side of the buttonhole has been completed the end of the lever 104 will be in the dotted line position Fig. 11 and during the return movement of the frame 1 as the second side of the buttonhole is being sewed the bevelled face 114 of the lever 104 will engage the pin 109 and depress the latter, thus allowing the end of the lever to pass over the pin without being operated. When the frame 1 has had its complete return movement the parts are in the relative position shown in Fig. 2, the end of the lever 104'having passed off from the pin 109 so that the latter can rise under the influence of the spring 113. With the parts in this position the pin is adjacent the cam 'face 111 so that upon the next forward movement of the frame 1 said pin will actuate the lever 104.- This pin and bevelled face 114 thus form a sort of switch cam which is operative during the movement of the frame in one direction but is inoperative during the movement in the opposite direction.

It will be noted that theunder thread cutter 57 operates above the throatwhile the upper thread cutter '49 operates beneath the of upper thread, which loop is immediately pulled out from'th-e cloth by the pull-off 53, and subsequently the under thread cutter 57 is actuated to cut the under thread and stay cord, if one is used,above the throat plate.

While I- have illustrated hereina selected embodiment of the invention I do not wishto be limited to the constructional features shown. r

Iclaim-rf V v In a buttonhole sewing machine, the combination. with stitch-forming mechanism, of buttonhole-cutting mechanism comprising two buttonhole-cutting elements movable relative to each other, anda thread cuttersecured to one of said elements.

2. In a buttonhole sewing machine, the combination with stitch-forming mechanlsm,

of buttonhole-cutting mechanism comprising two [co-operating cutting members, and a thread cutter carried by one member.

3. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of buttonhole-cutting mechanism comprising a cutter and a cutting block: movable toward and from .each other and a thread cutter carried by one of said elements.

' 4-. In abuttonhole sewing machine, the

combination with stitch-forming mechanism,

of buttonhole-cutting mechanism comprising.

a buttonhole'cutter movable into and out of cutting position, a block co-operating with the cutter, and a thread cutter carried by the buttonhole cutter.

5. In a. buttonhole sewing machine, the combination with stitch-forming mechanism, of buttonhole-cutting mechanism comprising a buttonhole cutter movable horizontally into. and out of operative position, a cutting block co-opera'ting with the cutter and a thread .cutter 7 carried by the buttonhole" cutter.

zontally-moving slide carrying the other member, means actuated by the lever to give 7 movement to the slide and thereby bring the member carriedthereby into operative position, and a thread-trimming knife carried by the slide. I x

7. Ina buttonhole sewing machine, the combination with stitch-forming mechanism for 'concatenating an upper and an under thread, of buttonhole-cutting mechanism comprising two buttonhole-cutting elements movable relative to each other and means secured to oneof said elements to cut the upper thread. I

'8. In a buttonhole sewing machine, the combination with stitch-forming mechanism for concatenating an upper and an under thread, of buttonhole-cutting mechanism comprising two co-operating cutting mem-f bers, and a thread cutter carried by. one of saidinembers for cutting the upper thread." 9. In a buttonhole sewing machine, the'l' combination with stitch-forming mechanism. for concatenating an upper -.and an under thread, of buttonhole-cutting mechanism comprising two c'o-operating cuttingmembers, a lever carryingone of said members, a horizontally-moving slide on which the other member is mountet means'to'move the slide to bring the cutting member carried thereby into operative position, andathread cutter fortrimming theupper' thread carried by, the slide -10. In a buttonhole sewing machine,'the combination with stitch-forming mechanism comprising upper thread handling mechanism and under thread mechanism arranged so that when the machine comes'to rest a loop of upper thread is retained by the under thread mechanism, of buttonhole-cutting mechanism comprising two co-opera'ting cutting members, and means carried by one member for cutting one leg of said loop of upper thread; 11. In a buttonhole sewing machine, the combination with stitch-formingmechanism comprising upper" thread handling mechanism and under thread mechanism arranged so that" when the machine comes to *rest a loop of'upper J thread is re its operative movement at the end of the sewing operation, and knife carried by said slide for cutting one leg of said loop of up. per thread. i

r 12. In a buttonhole sewingmachine, the

Ill

combination with stitclrforming mechanism comprising upper thread handling mechanism and under thread mechanism arranged so that when the machine comes to rest a loop of upper thread is retained by the under thread mechanism, of buttonhole-cutting mechanism comprising two co-operating cutting members, means carried by one member for cutting one leg of said loop of upper thread, and means to pull the cut loop out from the work.

13. In a buttonholc sewing machine, the combination with stitch-forming mechanism con'iprising upper thread handling mechanism' and under thread mechanism arranged so that when the machine comes to rest a loop of upper thread is retained by the under tlnread mechanism, of buttonhole-cutting mechanism comprising two co-operating cutting members, a horizontally-moving slide on which one oi the members is mounted, means to give said slide its operative movement at the end of the sewing operation, a knife carried by said slide for cutting one leg of said loop o'l? upper thread, and means to pull the cut loop out from the work.

Ll. In a buttonhole sewing machine, the eon'lbination with stitch-forming mechanism for concatenating an upper and under thread and constructed so that when the machine comes to rest a loop of upper thread is retained by the under thread mechanism, off button-holecutting mechanism comprising two cooperating cutting elements, a lever on which one element is mounted, a cam for operating said lover, a slice on which the other cuttine element is mounted, means actuated by said lever to move the slide to carry the cutting element thereon into operative position, a thread cutter carried by said slide and adapted to cut one leg of the loop of upper thread, and means actuated by said lever to pull said loop back through the work.

15. In a buttonhole sewing machine, the combinatitm with stitch-forming mechanism, of means to rotate said mechanism at the end ot the buttonhole, and means actuated by the stitch-forming mechanism rotating means to out the thread.

16. In a buttonhole sewing machine, the combination with stitch-forming mechanism dapted to concatenate an upper and an under thread, of means to rotate said mechanism at the end of the buttonhole, and means actuated by the devices by which the stitch-forming mechanism is rotated to cut the under thread.

17, in a buttonhole sewing machine, the combination with stitch-forming mechanism mnnprising upper and under thread handling mechanism, a. turret carrying the under thread mechanism, means to rotate the turret at the end ot the buttonholc, and means actuated by the turretrotating means to cut the under thread.

18. In a buttonhole sewing machine, the combination with stitch-forming mechanism comprising upper thread mechanism and under thread mechanism, a turret carrying the under thread mechanism, said turret having a throat, means to rotate the turret at the end of the buttonhole, and means actuated by the turret-rotating means to cut the under thread above the throat and beneath the work.

19. In a buttonhole sewing machine, the combination with stitch-forming mechanism comprising upper thread mechanism and under thread mechanism, a turret carrying the under thread mechanism, said turret having a throat, means to rotate the turret at the end of the buttonhole, means actuated by the turret-rotating means to cut the under thread above the throat and beneath the work, and means on the turret to grip the under thread. i

20. In a buttonhole sewing machine, the combination with stitch-forming mechanism for concatenating an upper and an under thread, of means to rotate said mechanism at the end of the buttonhole, means actuated by the devices by which said mechanism is rotated to cut the under thread and means to hold. the cut end.

21. In a buttonhole sewing machine, the combination with stitchdorming mechanism for concatonating an upper and an under thread, of means to rotate said mechanism at the end of the buttonhole, a cutter for the under thread, a gripping finger to grip the under thread, n'ieans actuated by the devices by which said mechanism is rotated to give the cutter its cutting movement and means to control the operation of the gripping finger.

22. In a buttonhole sewing machine, the combination with stitch-forming mechanism for concatenating an upper and an under thread, means to rotate said mechanism at the end of the buttonhole, a cutter for cutting the under thread, a springpressed gripping finger to grip the under thread, means normally holding the gripping linger in inoperative position, means actuated by the devices by which said mechanism is rotated to operate the cutter and means to release the gripping finger.

In a buttonhole sewing machine, the combination with stitch-forming mechanism for concatenating an upper and an under thread, of means to rotate said mechanism at the end of the buttonl'iole, a tension for the under thread, means actuated by the devices by which said mechanism is rotated to cut the under thread, and means to grip the cut on d and to relieve the tension.

24. In a buttonhole sewing machine, the combination with stitch-forming mechanism for concatenating an upper and an under thread, means to rotate said mechanism at the end of the buttonhole, of a tension for the under thread, means actuated by said lastnamed means to cut the under thread, means to grip the cut end and to relieve the tension, and means to draw off a length of under thread w ien the tension is released.

25. In a buttonhole sewing'machine, the combination with stitch-forming mechanism for concatenating' an upper and an under thread, of means to rotate saidmechanism at the end of the buttonhole, means actuated by the last-named means to cut the under thread, means to grip the cut end, and means to release said cut end after the stitching has begun on the next buttonhole.

26. In a buttonhole sewing machine, the combination with stitch-forming mechanism for concatenating an upper and an under thread, of means for rotating said mechanism at the end of the buttonhole, a spring-pressed gripping finger to grip the thread,a cutter to cut the thread between the gripping finger and the work, means normally holding the gripping finger inoperative, means operated by the devices by which said mechanism is rotated to operate the cutter, means to release the gripping finger, whereby the latter becomes operative to grip the thread, and means to render thegripping finger inoperative after the first stitches have been formed on the next succeeding buttonhole.

27. In a buttonhole sewing machine, the

combination with stitch-forming mechanism and work-holdmg means having a relativemovement, means to rotate said mechanism at the end of the buttonhole, a thread-gripping finger to grip the under thread, a cutter to out said threadbetween the gripper and the work, means actuated by the devices for rotating saidstitch-forming mechanism to operate the cutter, means to render'the gripping finger operative, and means operated by said relative movement to release the gripping finger after the stitching has begun on the next buttonhole. 7

28. in a'buttonhole-sewing machine, the combination with stitch-forming mechanism, of buttonhole-cutting mechanism, means to cut the under thread at the end of the sewing operation, and means controlled by the but tonhole-cutting mechanism to grip the under thread.

29. In a buttonhole-sewing machine,- the combination with stitch-forming mechanism, of buttonhole-cutting mechanism, means to cut the under thread atthe end of the sewing o eration a sorin actuated threadri ping linger to grip the under thread between the point where it is cut and the source of supply, means normally holding the'finger inoperative, and means actuated by thebuttonhole-cutting mechanism to release said finger after the thread has been cut.

30. In a buttonhole-sewlng machine, the combination wlth stltch-forming' mechanism,

of buttonhole-cutting mechanism, means to In testimony whereof, I have signed my name to this specification.

J OHN KIEWICZ.

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