US1846398A - Thread trimmer for buttonhole sewing machines - Google Patents

Description

J. KlEWlCZ 1,846,398 THREAD TRIMMER FOR BUTTONHOLE SEWING MACHINES Feb. 23, 1932.

, 1930 6 Sheets-Sheet 1 Filed March 19 lnvenToT. LJohn KIBWIC ATTys.

THREAD TRIMMER FOR BUTTONHOLE SEWING-MACHINES Filed March 19, 1930 6 Sheets Sheet 2 Fig. 2.

IE @F l G s i@ 87 30 5 3o Z S F g s 8 7 36 Q 60 5; {ILL 64 7 lnvenTcm g John Kievvicg A0 58 bymwaw ATTys.

Feb. 23, 1932. J. KIEWICZ 1,346,393

THREAD TRIMMER FOR BUTTONHOLE' SEWING MACHINES Filed March 19, 1930 6 Sheets-=Sheet 5 Fig.8.

as 75 I 94 3 J. KIEWICZ 1,846,398 THREAD TRIMMER FOR BUTTONHOLE SEWING MACHINES Feb. 23, 1932.

Filed March 19, 1930 6 Sheets-Sheet 4 a7 \07 I02 a lnvenToT Uohn K i aw i133 ywwyw ATTys.

Feb. 23, 1932. J, w z 1,846,398

THREAD TRIMMER FOR BUTTONHOLE SEWING MACHINES Filed March 19, 1930 6 Sheets-Sheet 5 Fig.6.

i Fig. 7.

I fl l'nvenTor. Uohn Kiev'vicg byWdW AT Tys.

Feb. 23, 1932. 1,846,398

THREAD TRIMMER FOR BUTTONHOLE SEWING MACHINES J. KEEWICZ Filed March 19, 1930 6 Sheets-Sheet 6 lnvenTor.

do h n K i aw i c 3 b a mwS Wj Anya Patented Feb. 23, 1932 UNITED STATES PATENT OFFICE JOHN KIEWIGZ, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE REESE BUTTON HOLE MACHINE COMPANY, OF BOSTON, MASSACHUSETTS, A. CORPORATION OF MAINE THREAD TRIMMER FOR BUTTONHOLE SEWING MACHINES Application filed. March 19, 1930. Serial No. 436,926.

This invention relates to thread-trimming means for sewing machines and particularly for buttonhole sewing machines.

The invention is herein shown as applied to a two-thread buttonhole sewing machine and it comprises novel means for cutting both the upper thread and the under thread as well as the stay cord, if one is used.

According to one feature of the invention, the means for cutting one of the threads is actuated by the buttonhole-cutting mechanism so that when the buttonhole is cut at the end of the sewing cycle the thread will be sinmltaneously cut.

Still another feature of the invention relates to a novel means for holding both the upper and the under thread after they have been severed and until the first stitches have been made on the next succeeding buttonhole.

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

In order to give an understanding of the invention I have illustrated in the drawings a selected embodiment thereof which will now he described after which the novel features will he pointed out in the appended claims.

Fig. 1 is a side view of a buttonhole sewing machine embodying my invention;

Fig. 52 is a plan view with the head removed and showing the means for operating the thread trimmer for the upper thread by means of the huttonhole-cutting mechanism;

Fig. 3 is an under side view of the bed showing the means for actuating the under thread cutter; i

Fig. 4. is a plan view of the work-supporting plates illustrating the cutter for the under thread;

Fig. 5 is a fragmentary side view illustrating the action of the hold-down for the cloth while the under thread trimmer is operating;

Fig. 6 is a front view of the sewing machine illustrating the thread holder for the upper thread Fig. 7 is a fragmentary view of Fig. 6 showing the operation of the upper thread holder;

Figs. 8, 9, 10 and 11 are different views of the turret carrying the under thread mechanism and showing the upper thread cutter and the means for holding the under thread.

The buttonhole sewing machine herein shown is of the typewhich comprises a bed frame 1 carrying work-holding means and a second frame, which I will refer to as a stitch frame, that carries the stitch-forming mechanism. These two frames are mounted for movement relative to each other to provide for the sewing along the edge of the buttonhole and to provide for carrying the parts from louttonhole-stitching to buttonhole-cutting position and vice versa, and in the particular construction herein shown the stitch frame is mounted to move back and forth on the bed frame 1.

When the sewing machine completes its huttonholesewing cycle the stitch-forming mechanism and work-holding means are in huttonhole-cutting position and when the machine is started the stitch frame will first have a quick movement which will carry the parts into stitching position and then will have a slow feeding movement while the stitching is being formed on the buttonhole, and when the stitching has been completed it will have another quick movement to carry the parts into buttonhole-cutting position again, this being the customary sequence 0 operations in the sewing of a buttonhole.

The stitch frame comprises the head portion 2 having the usual overhanging arm 3 in which reciprocates the needle bar 4 carrying the upper needle 5 forming part of the stitch-forming mechanism. This stitch frame also includes the cam casing 6 which encloses the main cam 11 that controls the operations of the machine. This cam casing is rigid with both the head 2 and the frame portion 7 in which is mounted the usual turret 8 carrying the under thread mechanism and the usual throat 40.

This under thread mechanism may be of any usual type but is herein shown as comprising two loopers 9 and two loop spreaders 1O, said loopers and loop Spreaders co-operating with the needle 5 to produce the stitching as usual in buttonhole sewing machines of this type. One of the loopers 9 is threaded with the under thread 60, but the other is a non-threaded looper.

The work-holding means comprises the usual clamp plates 48 on which the work w is supported, and the work clamps 95 which clamp the work against the clamp plates.

It will be understood that the turret 8, as well as the needle bar 4 are rotated at one end of the buttonhole to form the eye and also have a rotative movement at the other or finishing end of the buttonhole to bring the parts back to normal position. This rotary movement is derived as usual from the main cam 11 which is situated within the cam casing 6, said cam being constructed to actuate a lever 12 pivoted to the cam casing at 13, which lever is connected by a link 14 to an arm 15 rigidly carried by a vertical rockshaft 16. This rock shaft 16 has the two gear sectors 17 and 18 which mesh with gears 19 and 20 mounted on the turret 8 and the needle bar 4 respectively. The main cam 11, of course, is properly shaped to give the movement to the lever 12 at the proper times in the sewing cycle. This means for rotating the stitch-forming mechanism is such as is commonly employed in buttonhole sewing machines. 7

The machine herein shown is also provided with usual buttonhole-cutting mechanism. This comprises the two cutting elements 21 and 22, one of which is a cutting blade and the other of which is a cutting block. As herein illustrated the element 21 is the cutting block and the element 22 the cutting blade.

The cutting block is mounted on the usual cutter lever 23 which is pivoted to the head 2 at 24. Said lever has at its rear end a follower 25 adapted to be engaged by a cutter cam 26 mounted on the main cam 11. The cutter lever isacted on by a spring 27 which normally holds it in elevated position.

The cutter member 22 is ofthe type which is mounted to move backwardly and forwardly from a retracted inoperative position to a forward operative position.' This cutter element is carried by a block 28 which is mounted on a slide 29 adapted to slide in ways 30 carried by the portion 7 of the stitch frame. The slide 29 is given its backward and forward movement directly from the main cam 11 and for this purpose said cam 11 has a cam groove 31 therein in which is received a follower carried on a stud 32 which is mounted 5 on an arm 33 that extends rearwardly from the slide 29. The cutter element 22 is thus given its forward and backward movement directly from the cam 11.

The parts thus far described are, or may be, all as usual in buttonhole-sewing machines of this type and, form no part of the present lnvention.

As stated above one feature of the present invention relatesto a novel means associated with the buttonhole-cutting mechanism for cutting the upper thread at the end of the sewing operation on any buttonhole.

As usual in buttonhole sewing machines of this type the stitch-forming mechanism is so constructed that when the machine comes to rest with the needle raised as shown in Fig. 1, there will be a loop 34 of the upper thread 35 retained by the non-threaded looper 9 and its loop spreader 10 of the under thread mechanism. In other words, the upper thread 35 will extend fromthe eye ofthe needle 5 through the work at the last stitch and thence around the non-threaded looper and loop spreader to form the loop 34, said thread extending back to and being anchored in the workat the last stitch.

The present invention provides novel means for cutting the side of this loop 34 which leads to the work at the time that the cutter 22 is moved into its operative cutting position after the completion of the buttonhole. This is accomplished by, means of a cutter member 36 which is carried by a resilient arm 37 that is secured to the turret 8.

At the time that the stitch-forming mechanism comes to rest at the completion of the buttonhole theturret is in the position shown in Fig. 2, in which position the resilient arm 37 will be on the side of the turret toward the buttonhole-cutting mechanism. At this time the looper mechanism is so disposed that the loop 34 will be in a substantially vertical plane extending fore and aft of the sewing machine as illustrated in Fig. 10. The resiliency of the arm 37 normally holds the cutter 36 in its retracted position and means are provided for swinging the cutter forwardly into its thread-cutting position shown in dotted lines Fig. 10 by the forward movement of the cutter member 22. For this purpose the block 28 is provided with a hunter 38 and the arm 37 is provided with a lateral extension 39 which is situated in the path of the hunter when the turret is in the position shown in Fig. 2.

WVith the parts in this position the forward movement of the slide 29 which brings the buttonhole-cutting element 22 into its operative position causes the hunter 38 to engage the extension 39 thereby swinging the cutting element 36 forwardly and bringing the cutting edge thereof against the side of the loop 34 leading to the work thereby severing said loop. This cutting element 36 passes direotly under the throat plate 40 of the turret.

When the buttonhole has been cut and the slide 29 is retracted the resiliency of the arm 37 will return the cutter to its normal or retracted position. 7

I have also provided herein means for engaging the upper thread above the work and pulling the cut loop 34 back through the work so as to leave a sufiicient length of thread projecting from the eye of the needle 5 to permit of the proper formation of the first stitch on the next buttonhole. This pulling out of the upper thread is accomplished by a hookshaped pull-off arm 41 which is carried in a swinging carrier 42 that is pivotally mounted in bearings 43 carried by the cutter lever 23. The pull-off arm 41 is normally in its retracted position shown in Fig. 6 in which position it is located on one side of the needle 5.

fllince the pullpfi' arm 41 is mounted on the forward end of the cutter lever 23 it will have a down and up swinging movement as the buttonhole is cut. During the downward swinging movement of the forward end of the cutter lever 23 the arm 41 is swung laterally into the position shown in Fig. 7, in which position the hook portion 44 thereof will wipe past tl e upper thread so that said thread will lie in the hook portion 44. d hcn the lever 23 has its retracting movement the hook portion 44 will be raised and also moved laterally thereby engaging the upper thread 35 and pulling the cut loop out from the work as shown in Fig. 1.

This movement of the pulled arm 44 is derived from a cam arm 45 which is attached to the head 3 and is situated so that as the forward end of the cutter lever swings downwardly into the buttonhole-cutting position the end of the carrier 42 will engage the cam portion of the arm 45 and will be caused thereby to swing laterally into the position shown in Fig. 7. When the cutter lever 23 is raised again to its normal position shown in Fig. 1 the carrier 42 will be swung back to its normal position by means of a suitable spring 46. This construction has the advantage that both the cam arm 45 and the pull-off arm 41 are normally located considerably above the work and thus do not interfere with the manipulation of the work during the sewing operation.

In moving from the position shown in Fig. 6 to that shown in Fig. 7 the hook 44 of the pull-elf arm 41 wipes by the upper thread and in order that said hook may properly engage the upper thread it is desirable that it should be taut at this time. Consequently, I have so arranged the dimension of the earns 26 and 31 that the cutter 36 will cut the upper thread just after the cutter lever 23 has made its cutting movement and hence after the hook 444 of the arm 41 has wiped by the upper thread as shown in Fig. 7 and before the cutter lever is restored to its normal position. In other words, the cutting action of the thread cutter 36 occurs while the toe 25 of th e cutter lever 23 is riding over the cam 26.

The means for cutting the under thread is t similar to that shown in my co-pending appl cation tderial No. 269.985, filed April 14, 1928. It comprises a cutter member 47 which is situated above the clamp plates 48 but which operates beneath the work. Said cutter mounted on a rock shaft 49 carried by the bed plate and which is provided with a cutting edge 50 situated to engage the threads extending downwardly from the work and thus out said threads close to the work. These threads may include the usual under thread 60 as well as the stay cord, if one is used.

This cutter 47 is actuated by the mechanism by which the stitch-forming mechanism, including the turret 8, is rotated.

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 given a half rotation to return it to proper position to begin the sewing on the next buttonhole and movement of the stitch-forming mechanism that the under thread trimmer 47 is actuated.

The rock shaft 49 on which the cutter 47 is mounted has rigid therewith an arm 51 located beneath the bed frame 1 and this arm is adapted to be engaged by a pin 52 carried by a bar 53 which is arranged to have a transverse reciprocating motion. At one end the bar is slotted as shown at 54 and-in the slot is received a guide screw 55 screwed to the T bed frame 1. At the other end the bar 53 is connected to a lever 56 pivoted at 57 to the bed frame and having at its rear end a catch 58 adapted to be engaged by a dog 59 situated at the end of the lever 12. The bar 53 is normally held in the position shown in Fig. 3 by the spring 111.

At the end of the sewing operation the parts are in the position shown in full lines Fig. 3, but as the lever 12 is turned to give the stitch'forming mechanism its rotative movement at the end of the sewing on the buttonhole the dog 59 engages the catch 58 and swings the lever 56 clockwise Fig. 1 thereby moving the pin 52 to the right and by its engagement with the arm 51 causing the cutter 47 to have its thread-cutting movement.

The present invention also includes a novel means for pulling off a length of under thread 60 from the source of supply and then gripping said thread immediately beneath the throat 40 just before the cutter 47 is operated to cut the under thread.

The thread pull-01f derives its operative movement from the movement of the slide 29 which carries the buttonhole-cutting member 22. The thread-gripping device derives its motion from the main cam 11 through a separate train of mechanism.

The under thread pull-ofl' is indicated at 61 and is in the form of a finger which is secured to the block 28 carrying the buttonhole-cutting element 22. The under thread 60 is led to the turret through a guiding tube 62 and then passes to the usual tension device 63 and from the latter passes through a guiding member 64 and thence to an eye 65 formed on the end of a resilient take-up arm 66. From said eye 65 the thread passes to one of the loopers 9 and thence to the work through it is during this rotative finger 68 which is l0 and vice versa.

surface 79.

the sewing opening in the throat 40 all as usual.

WVhen the stitch-forming mechanism comes to rest at the end of the buttonhole the turret is in the position shown in Fig. 2 with the guide eye 64 closely adjacent to the offset end 670f the pull-off finger 61.

When the slide 29 is movedforwardly to bring the buttonhole cutter into its operative buttonhole-cutting position the offset end 67 of said finger will engage the under thread just above the guise eye 6%. The movement of the pull-off finger 61 is from about the full line position F 2 to the dotted line posi tion and the engagement of the pull-off finger with the thread during the movement of the finger from the full to the dotted line position Fig. 2 will draw length of thread from the source of: supply. This occurs before the under thread cutter 47 is given its thread-cutting mo *ement.

, The means for gripping the under thread just before said t iread is cut and holding the cut end thereof until the stitching on the next buttonhole has begun comprises a gripping adapted to griptne under thread 60 between itself and the under side of the throat -10. This grippin finger 68 operates in an opening 69 formed in the stand ard 70 of the turret 8 and it is pivotally connected at 71 to an upright arm 72 which is secured to a block that is pivoted to the turret at 73 so that the arm 72 can swing to ward and from the post 70, or from the position shown in Fig. 11 to that shown in Fig.

The gripping member is normally held in its operative position shown in Fig. 10 through the medium of a. pulling spring 74 which is connected on one end to the block 75 and at the other end to an anchoring arm 7 6 rigid with the turret.

thinner at the end, said thinner end being con nected with the thicker end through the cam When the gripping member 68 is carried into its retracted position the spring 7 7 maintains its under surface in contact with the edge 7 8 of the opening 69 and because of the shape of the under face of said member the free end of the gripper member will be lowered or moved away from the under face of the throat 40 during the retracting movement of said member.

\Vhen the stitch-forming mechanism comes to rest the loopers are in the position shown in Fig. 9with the threaded looper in the retracted position so that the under thread 60 extends from the sewing opening of the throat laterally to the looper as seen in Fig. 9. V7 hen the thread, gripper 68 has been carried into its retracted position as shown in Fig. 11 the end of said member is at one side of and below the portion of the under thread extending from the throat to the threaded looper as indicated in Fig. 11. 7

Just before the under thread is cut by the action of the thread cutter 47 the arm 72 is swung from the position shown in Fig. 11 to that shown in Fig. 10 thereby carrying the thread gripper 68 forwardly by the action of the spring 7 4.

The initial forward movement of the thread gripper 68 will be in asubstantiallyhorizontal position with the point thereof lowered but when the cam surface 79 of said gripper engages the edge 78 the gripper will be raised into engagement with the under face 80 of the throat as shown in Fig. 10. During the initial forward movement of the gripper 68 the free end thereof will pass beneath the portion of under thread extending between the sewing opening in the throat 40 and the looper and when said gripper is raised by the engagement of the cam surface 79 with the lower edge 78 of the opening 69 the under thread will be clamped between said gripper and the under face 80 of the throat. The thread is held gripped until the first few stitches have been formed on the next buttonhole and then the gripping device is momentarily swung into its backward position thereby to release the thread end.

' For swinging the arm 72 from its forward position shown in Fig. 10 to its retracted position shown in Fig. 11 against the action of the spring 74 I have provided the following mechanism.

The block 75 has rigid therewith a quadrant-shaped arm 81. At the end of the sewing on the buttonhole the turret is in the position shown in full lines in the drawings and at this time the free end of the quadrant-shaped lever 81 will be situated directly over an arm 82 carried by a hub 83 that is pivotally mounted at 84 to the portion 7 of the stitch frame. This hub or sleeve 83 has another arm 85 rigid therewith which is pivotally connected at 86 to another arm 87 fast on a rock shaft 88 that is journalled in bearings formed on the cam casing 6. The rock shaft 88 has an arm 89 fast thereto which carries a follower roll 90 adapted to engage a cam surface 91 formed in the under side of the main cam 11.

The follower 90 is maintained in engagement with the under face of the cam 11 through the medium of a spring 92 and the cam face 91 is made with a depression into which the follower 90 is carried by the spring per is normally held in 81 during the movement 92 at the proper time in the sewing cycle. When. the follower rides into the depression of the cam 91 the rock arm 89 will be raised, the arms 87 and 85 will be lowered and the arm 82 will be raised. At this time the arm 82 is underneath the end of the quadrantshaped arm 81 as above described so that the raising of the arm 82 also raises the arm 81 and thereby throws the arm 72 into its backward position shown in Fig. 11 thus retracting the thread gripper 68. As soon as the cam 11 has turned sufliciently so that the follower 90 has passed out of the depression in the cam surface 91 the spring 92 will restore the parts to their normal position thus allow ing the spring 7 a to give the thread gripper 68 its thread-gripping movement.

As stated above the thread gripper 68 engages the under thread and grips it against the under face of the throat 10, this occurring just before the under thread is cut by the cutter 4C7. The thread gripper maintams its gripping engagement with the thread until after the first few stitches have been formed on the nextbuttonhole at which time the thread gripper is again moved to its inoperative position. This is accomplished through the bodily movement of the stitch frame which occurs during the formation of the side stitches on the buttonhole.

It has been stated that when the stitchforming mechanism comes to rest the turret is in the position shown in full lines in the drawings. Between such time and the time when the stitch-forming mechanism is set 1n operation again the turret is rotated through approximately 180 which will bring the quadrant-shaped arm 81 around into the dotted line position shown in Fig. 3. The turret remains in this position during the sewing on the first side of the buttonhole and then makes a half rotation. when sewing around the eye of the buttonhole.

t will be understood that the thread gripits forward position by the spring 7 at and for throwing it into its retracted position when the stitching on the buttonhole begins for the purpose of releasing the end of the under thread I have pro vided a thread-releasing arm 98 which is secured to the stationary bed plate 1 by means of screws 94:.

The free end of this arm is in position to be engaged by the end of the quadrant arm of the stitch frame which occurs as the first few stitches on the buttonhole are being sewed. During this movement the curved end 9 10 of the quadrant arm 81 will wipe over the free end of the arm 93 thereby raising the quadrant arm and throwing the thread gripper into its retracted position shown in Fig. 11. This will result in releasing the thread end.

As soon as the quadrant arm 81 has passed off from the thread-releasing arm 93 the spring 7 4 will return the thread gripper 68 to its normal position shown in ig. 10. This release of the gripper is thus accomplished by the relative movement between the stitch-forming mechanism and the workholding means which occurs during the stitching on the buttonhole. a

In this sewing machine the work is held during the sewing operation by usual work clamps 95, 95 and said clamps are released automatically at the end of the sewing operation, as is customary in buttonhole sewing machines. This release of the clamps occurs before the cutter 47 is actuated to cut the under thread and in order to hold the work stationary relative to the open work clamps while the thread is being cut and after the clamps are released I have provided a holddown device which is normally inoperative but which is thrown into engagement with the work just before the knife .47 is actuated. This hold-down member is in the form of a hold-down finger 96 carried by a block 97 whichis pivoted at 98 axially with the arms 99 which carry the work clamps 95. j

The hold-down arm is normally maintained in released position by means of a pulling spring 100 which is connected at one end to the block 97 above its pivot and at the other end to the member 101 to which the block 97 is pivoted.

Means are provided for throwing the holddown arm 96 into engagement with the work w as shown in Fig. 5 just as the work clamps 95 are released and during the time that the cutter 47 is being actuated to cut the under thread beneath the work. This operative movement of the hold-down finger 96 is secured through the relative movement between the stitch-forming mechanism and w0rkholding means that occurs after the stitching has been completed and while the parts are being carried from buttonhole-stitching to buttonhole-cutting position. As stated above, this relative movement is derived from the movement of the stitch frame on the bed frame 1.

To make use of this movement for actuating the arm 96 the block 97 is provided with a rearward extension 102 formed with a cam face 103 and the head 2 is provided with a plate 104 having a lateral extension 105. The rear edge of this extension 105 is bevelled, as shown at 106. During the sewing on the buttonhole the. location of the head 2 is such that the plate 104; is in the rear of the block 97 but during the movement of the head which brings the parts into buttonhole-cutting position the plate 104 will be moved to the left into the position shown in Fig. 5 and during this movement the extension 105 will engage the cam face 103 and raise the rear end of the block 97 thereby swinging the hold-down finger 96 into engagement with the work.

ficiently to The hold-down finger 96 will be main.- tained in engagement with the work as shown in Fig. until the head 2 has moved sufwithdraw the arm 105. from beneath the rearward extension 102 of the block 97. During this time the cutter 17 is actuated so that the under thread is out after the work clamps have been raised and while the hold-down arm 96 is in its operative position.

By the time the head 2 has arrived at the buttonhole-cutting position the lateral exten- $1011 105 will have wiped past the end 102 of the block 97 and will have come into alignment with the recess 107 formed on the under side of the block. When this occurs the spring 100 will raise the hold-down arm so that when the sewing cycle is completed the arm is in its elevated position.

i, which plate 104 toward the right, Fig. 5.

The cutting of the under thread by the cutter 47 occurs during the final movement of the head 2 which takes place after the stitchforming mechanism has come to rest and by the parts are carried into buttonholecutting position; When the sewing machine is started again for sewing the next buttonhole the head has a backward movement which will carry the During this backward movement the face 108 of the block engages the cam face 106 thereby again throwing the hold-down arm 96 into engagement with the work. This movement of the hold-down arm, however, performs no useful purpose as at this time the work is already clamped by the work clamps 95.

If it is desired to have the hold-down finger in engagement with the work while the clamps M 95 are closed against the work then the block 97 may be provided with a projection 107 which is situated to be engaged by one of the clamp supporting arms 99 when the clamps are closed. The engagement of the arm 99 with the projection 107 will turn the block 97 against the action of the spring 100 and thus close the hold-down arm against the work as shown in Fig. 1. In such case, the hold-down arm 96 will rise from the work when the clamps are opened but will be closed by the engagement of the cam face 103 with the extension 105, and will be held closed while the cutter 47 is actuated.

While I have illustrated herein a selected embodiment of my invention, I do not wish to be limited to the constructional features shown.

I claim:

1. In a buttonhole sewing machine, the

- 66 combination with stitch-forming mechanism,

of buttonhole-cutting mechanism including a pivoted cutting element and a second cutting element movable relative to the pivoted cutting element in the direction of the length of the buttonhole, a thread-cutting member supported independently from the buttonhole-cutting elements, and means to give the thread-cutting element its cutting movement by the movement of the said second buttonhole-cutting element.

2. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of buttonhole-cutting mechanism including a pivoted cutting element and a second cutting element co-operating therewith and movable relative to the pivoted cutting element in the direction of the length of the buttonhole, a thread-cutting member supported independently of the buttonhole-cutting elements, and a hunter associated with the second buttonhole-cutting element and adapted to engage and actuate the thread cutter when the buttonhole cutting element has its operative movement.

3. In a buttonhole sewing machine, the combination with stitch-forming mechanism including under thread mechanism, of buttonhole-cutting mechanism including a buttonhole-cutting element movable in the di rection of the length of the buttonhole, a thread cutter, a resilient arm on which said cutter is mounted, and means associated with the buttonhole-cutting element to engage said arm and give the cutter its thread-cutting movement.

4. In a buttonhole sewing machine having upper and under thread mechanism, the combination with said under thread mechanism, of a turret on which said mechanism is mounted, buttonhole-cutting mechanism, means to actuate the same, a thread cutter carried by the turret, and means to operate the thread cutter by the buttonhole-cutting mechanism.

5. In a buttonhole sewing machine having upper and under thread mechanism, the comination with a turret supporting the under thread mechanism, of a thread cutter carried by said turret, buttonhole-cutting mechanism including a cutting element movable into and out of operative position, and means actuated by said element to actuate the thread cutter.

6. In a buttonhole sewing machine having upper and under thread mechanism, the combination with a turret supporting the under thread mechanism, of a thread cutter carried by said turret, buttonhole-cutting mechanism including a cutting element movable into and out of operative position, and means operated by said element as it moves into its operative position to actuate the thread cutter.

7. In a buttonhole sewing machine, the combination with stitch-forming mechanism for concatenating an upper and an under thread, of buttonhole-cutting mechanism including a cutting element movable into and out of operative position, andmeans actuated by the buttonhole-cutting element as it moves into cutting position to pull off a length of under thread.

8. In a buttonhole sewing machine, the

combination with stitch-forming mechanism for concatenating an upper and an under thread, of buttonhole-cutting mechanism, means to actuate said buttonhole-cutting mechanism, and means operated by said mechanism to pull off a length 01 under thread.

9. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of buttonhole-cutting mechanism, and a thread pull-oil for pulling thread from the source of supply actuated by the buttonholecutting mechanism.

10. In a butt-onhole sewing machine, the combination with stitclniorming mechanism for coneatenating an upper and an under thread, of buttonhole-cutting mechanism including a cutting element movable in the direction of the length of the buttonhole into and out of operative position, and an under thread pull-oif finger movable with said cutting element and operating to pull off a length of under thread when said element moves into cutting position.

11. In a buttonhole sewing machine, the combination with threeel-manipulating mechanism, of a turret supporting said mechanism, buttonhole-cutting mechanism including a buttonhole-cutting element movable into and out or operative position, and means associated with said element to engage the thread leading to said thread-handling mechanism and pull off a length thereof from the source of supply.

12. In a buttonhole sewing machine, the combination with a needle operating from above the work, of buttonholecutting mechanism including a pivoted lever, means to cut the upper thread beneath the work, a spring-actuated upper thread pull-oil device pivotally carried by said lever, and means to engage said pull-oil device as the lever moves into operative position thereby to place it in operative position to engage the needle thread between the needle and the work upon backward movement of said lever and thereby pull said thread back from the work.

13. In a buttonhol-e sewing machine, the combination with a needle operating from above the work, of buttonholecutting mech anism including two cutting elements, a lever on which one element is mounted, means to cut the upper thread beneath the work, a pull ofi finger pivotally mounted to said lever, and a stationary cam member adapted to be engaged by said linger as the lever turns to carry its cutting element into buttonholecutting position thereby to place said pull-oil finger in position to engage the needle thread between the needle and the work upon re turn movement of said lever thereby to pull said thread back from the work.

1%. In a buttonhole sewing machine, the combination with a needle operating from above the work, of buttonhole-cutting mechanism including two cutting elements and a lever carrying one of said elements, means to actuate said lever, means to cut the needle thread beneath the work, a pull-off finger pivotally mounted on said lever and adapted to swing laterally, said finger normally having a position at one side of the needle thread, and means to cause said finger to swing laterally into position to engage the needle thread when the lever moves into buttonholecuttingposition, whereby upon return movement of the lever the finger engages the me dle thread and pulls the latter back from the work. i

In a buttonhole sewing machine, the combination with stitch-forming mechanism and work-holding means adapted to have a relative movement during the sewing on the buttonhole and a further relative movement subsequent to the completion of the sewing, said work clamps being arranged to clamp the work during the sewing operation and to release the work when the sewing is completed, of means to cut the thread at the completion of the sewing, and a hold-down member actuated by said further relative movement to engage thework and hold it from movement relative to the work clamps while the thread cutter is operating.

16. In a buttonhole sewing machine, the combination with stitch-forming mechanism and work-holding means having a relative movement during the side stitching on the buttonhole and a further relative movement after the sewing has been completed, said work-holding means being arranged to clamp the work during the sewing operation and then to release the work, a thread cutter, means to actuate the same after the sewing operation has been completed and the work has been released, and a hold-down member actuated by said further relative movement to engage the work and hold it stationary relative to the work-holding means while the thread cutter is operatin 17 In a buttonhole sewing machine, the combination with stitch-forming mechanism and work-holding means having a relative movement during the sewing on the buttonhole, and a further relative movement after the sewing has been completed, said workholcling means comprising clamp plates and work clamps to clamp the work thereagainst and arranged to release the work on completion of the sewing, of means to cut the thread after the sewing has been completed and the workhas been released, and a holddown tinge actuated by said further relative movement to hold the work against and stationary relative to the clamp plate while the thread cutter is operating.

18. In a buttonhole sewing machine, the combination wit-h stitch-forming mechanism and work-holding means having a relative movement, of a rotary main cam by which the Operations of the machine are controlled, means to cut the thread at the end of the sewing operation, a thread-holding member to grip the thread between the cutting means and the source of supply, connections between said main cam and the thread-gripping member by which rotary movement of the cam operates the thread-gripping member at the end of the sewing operation, said member retaining its gripping hold on the thread until the next sewing operation has begun, and means actuated by said relative movement toractuate the thread-gripping member at the beginning of the sewing operation to release the thread. 7

19. In a buttonhole sewing machine, the combination with stitch-forming mechanism and work-holding means; having a relative movement, of a rotary main cam by which the operations of the machine are controlled, a thread-trimming element, means to actuate the same at the completion of the sewing on the buttonhole to trim the thread, a thread gripper to grip the thread between the thread-trimming means and source of supply, means actuated by the rotary movement of the main cam to operate the thread gripping means at the end of the sewing operation, said gripping means maintaining its gripping hold on the thread until the next sewing operation has begun, and means actuated by said relative movement to operate the thread-gripping means at the beginning of the sewing to cause it to release the thread.

20. In a buttonhole sewing machine, the combination with stitch-forming mechanism including upper and under thread mechanism, a turret on which the under thread mechanism is mounted, said turret having a throat plate, means to cut the thread at the end of the sewing operation, a swinging arm pivoted to said turret, a thread-gripping member carried by said arm and adapted to grip the under thread against the throat plate, a spring tending normally to hold said gripping member in thread-gripping position, means operative at the end of the sewing to actuate the arm thereby to carry the thread-gripping member into inoperative position and then to release said arm, whereby the thread-gripping member is caused to clamp the thread against the throat plate, and other means to actuate said thread-gripping means at the beginning of the sewing to release the thread.

21. In a buttonhole sewing machine, the combination with stitch-forming mechanism having upper and under thread mechanism, a turret on which the under thread mechanism is mounted, said turret having a throat plate, means to cut the under thread, a threadgripping member adapted to clamp; the under thread against the under side of the throat plate, means normally holding said member in its thread-clamping position, means operative at'the end of the buttonhole to move said member into retracted position and then to move said member forwardly underneath the under thread and then upwardly to clamp said thread against the other means operative at the beginning of the sewing on a buttonhole to again actuate said thread-clamping member to release the thread.

22. In a buttonhole sewing machine, the combination with stitch-forming mechanism comprising upper and under thread mechanism, a turret on which the under thread mechanism is carried, said turret having a throat plate, means to cut the under thread, a thread-gripping finger adapted to clamp the under thread against the under side of the throat plate, said finger being movable laterally with reference to the axis of the turret, means to retract said finger at the end of the sewing operation and then to move said finger forwardly beneath the under thread, and means to cause the finger to move upwardly against the throat plate during its forward movement thereby to clamp the thread against the throat plate, and other means to actuate said finger to release the thread at the beginning of the sewing operation.

23. In a buttonhole sewing machine, the combination with stitch-forming mechanism comprising upper and under thread mechanism, work-holding means, said stitch-forming mechanism and work-holding means having a relative movement, a turret onwhich the under thread mechanism is mounted, a throat plate carried by the turret, means to cut the under thread at the end of the sewing operation, an arm pivoted tothe turret, a thread-gripping finger carried by the arm and adapted to grip the under thread against the under side of the throat plate, a spring normally holding said arm in its threadgripping position, means to actuate the arm to cause the thread gripper to grip the thread at the end of the sewing operation, and other means rendered operative by said relative movement to actuate said arm thereby to re lease the thread at the beginning of the sewmg.

24;. In a buttonhole sewing machine, the combination with a needle operating from above the work, of under thread mechanism comprising a plurality of oscillating loopers moving in paths situated entirely beneath the work, one of which loopers is threaded with the under thread, a turret on which said under thread mechanism is mounted, said turret having a throat, a thread-gripping member carried by the turret and movable vertically relative to the throat, and means to actuate said member at the end of the sewing operation to clamp the under thread against the bottom of the throat.

25. In a buttonhole sewing machine,the

throat plate, and

combination with a turret, under thread mechanism carried thereby, a throat also carried by the turret and through which the under thread passes to the work, a threadgripping member carried by the turret but movable vertically relative to the throat to clamp the under thread against the bottom of the throat and means to actuate said thread-gripping member at the end of the sewing operation.

26. In a buttonhole sewing machine, the combination with stitch-forming mechanism having upper and under thread mechanism, a turret on which the under thread mechanism is mounted, said turret having a throat plate, a thread-gripping member adapted to clamp the under thread against the under side of the throat plate at the end of the sewing operation, means normally holding said member in its thread-clamping position, means operative at the end of the sewing on the buttonhole to move said member forwardly beneath the under thread and then upwardly to clamp said thread against the throat plate.

27. In a buttonhole sewing machine, the combination with stitch-forming mechanism having upper and under thread mechanism, a turret on which the under thread mechanism is mounted, said turret having a throat plate, a thread-gripping member adapted to clamp the under thread against the under side of the throat plate at the end of the sewing operation, means normally holding said member in its thread-clamping position, means operative at the end of the sewing on the buttonhole to move said member forwardly beneath the under thread and then upwardly to clamp said thread against the throat plate, and other means operative at the beginning of the sewing on a buttonhole to again actuate said thread-clamping member to release the thread.

28. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of buttonhole-cutting mechanism including a cutter movable into and out of operative position, a thread-cutting member in the form of a resilient arm having a cutting edge supported independently from the buttonholecutting element, and means to flex the arm thereby to give the thread-cutting element its cutting movement by the movement of the buttonhole-cutting element.

29. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of buttonhole-cutting mechanism including a cutting element movable into and out of operative position, a thread-cutting member supported independently from the buttonhole-cutting element, said thread-cutting element being in the form of a resilient arm having a cutting edge and a hunter associated operative movement to cut the thread when the buttonhole-cutting element has its operative movement.

30. In a buttonhole sewing machine, the combination with a needle operating from above the work, of buttonhole-cutting mechanism including two cutting elements and a pivoted lever on which one of said elements is mounted, means to cut the upper thread beneath the work, an upper threadpull-oif device carried by said lever and normally situated at one side of the length of needle thread extending from the needle to the work, means to move said pull-ofi device into position to engage the upper thread between the needle and the work when said lever is given its operative buttonhole-cutting movement, said pull-oil device operating on the upper thread during the return movement of the lever to pull said thread back from the work.

81. In a buttonhole-sewing machine, the combination with a needle operating from above the work, of buttonhole-cutting mechanism including a pivoted cutter lever, means to actuate said lever, means to cut the upper thread beneath the work, an upper thread pull-off device yieldingly carried by said lever and normally occupying a position at one side of the portion of upper thread extending from the needle to the work, and means to cause the said pullof device to move into position to engage said portion of the upper thread when said lever has its operative buttonhole-cutting movement, whereby upon backward movement of said lever the pull-ofi device will pull the cut end of upper thread back from the work.

32. In a buttonhole sewing machine, the combination with a needle operating from above the work, of a buttonhole-cutting mechanism including a pivoted cutter lever, means to cut the upper thread beneath the work, an upper thread pull-01f device movably carried by said lever, a spring acting on said device and normally holdin it in position at one side of the portion oft e upper thread extending from the needle to the work, means to move said pull-off device into position to engage said portion of the thread when the cutter lever has its operative buttonhole-cutting movement, said spring returning the pull-off to its normal position as the cutter lever is retracted, thereby pulling the end of cut upper thread back from the work.

In testimony whereof, I have signed my name to this specification.

JOHN KIEWIGZ.

with the buttonhole-cutting element and adapted to engage the arm and give it its

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