US1771047A - Thread trimmer for sewing machines - Google Patents

Description

J y 22, 1930. J. KIEWICZ THREAD TRIMMER FOR SEWIN G MACHINES Original Filed Dec. 15. 1925 5 Sheets-Sheet 1 John K ieWicg byMWJ W ATTys.

July 22, 1930. J. KIEWICZ THREAD TRIMMER FOR SEWING MACHINES Original Filed Dec. 15. 1925 5 Sheets-Shoot 2 \nvenToT. John Kiewic 3 by/ wMA M T Any;

July 22, 1930. J. KIEWICZ 1,771,047

THREAD TRIMMER FOR SEWIN G MACHINES Original Filed Dec. 15. 1925 5 Sheets-Sheet 3 InvenTor. John Kiewicg b /m WkM ATTys.

July 22, 1930. J. KIEWICZ THREAD TRIMMER FOR SEWING MACHINES oi-i inal Filed Dec. 15. 1925 5 Sheets-Shoot 4 lnvenTor.

15 .TN/ M 7 EM M #7 K HM nv 0 PW July 22, 1930.

J. KIEWICZ 1,771,047

THREAD TRIMMER FOR SEWING MACHINES Original Filed Dec. 15. 1925 v Figla.

5 Sheets-Sheet 5 Ma a \hveznTor.v John Kiewic v byw XM A TTys.

Patented July 22, 1930 re STATES PATENT. OFFICE JOHN KI-EVIICZ, OF BOSTON, MASSACHUSETTS, ASSIGZNOR TO THE REECE BUTTON HOLE MACHINE COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE THREAD rnnvnvrnn non snwnve cHInEs Application filed December 15, 1925, Serial No. 75,518, Renewed October 16', 19 29.

This invention relates to thread trimmers for sewing machines of that type which are power-actuated and are set in operation for trimming the thread by the action of the 5 stop motion in bring the stitch-forming mechanism to rest.

One of the objects of my present invention is to provide a novel thread trimmer which is arranged so that when the stop motion 10 brings the stitcl'i-forming mechanism to rest at the end of the scam the thread trimmer is automatically coupled to a constantly-moving part which gives the thread trimmer its thread-trimming movement, said thread trimmer being then automatically discon nected from the constantly-moving part after the trimming operation.

The thread trimmer herein shown has a thread holder associated therewith which holds the cut end of the thread leading to the source of supply and maintains such hold on the thread until the stitching on the next seamhas begun. The thread cutter is of the type which is arranged not only to trim the thread at the end of each sewing operation but also to trim the held end of the thread after the stitching has begun onthe next succeeding sewing operation, the cutter, there,- fore, cutting the thread twice for each sewing 39 operation, once at the beginning and again at the end.

A further object of the invention is to pro vide a novel thread trimmer which is actuated by a constantly-rotating member to trim the thread at the end of the sewing operation and is actuated by the means for operating the stitch-forming mechanism to trim the thread at the beginning of the sewing oporation.

Other objects of the invention are to improve thread cutters in various respect-s all as will be more fully hereinafter set forth. In order to give an understanding of the 4,5 invention I have illustrated in the drawings a selected embodiment thereof which will now be described after which the novel features will be pointed out in the appended claims. 1

Fig. 1 is a side View of aScWing machine C; embodying my invention;

Fig. 2 is an enlarged section ongthe line 22, Fig. 1 looking toward the right Fig. 3 is a section on the line 3-8,Fig. 2;

Fig. 4 is a view illustrating themeans for operating the thread cutter at the beginning of the sewing operation;

Fig. 5 is an enlarged section on the line 5'5, Fig. 1;

Figs. 6, 7 and 8 are side views of the thread cutter and holder showing the parts in different positions;

Figs. 9, 10 and 11 are plan views of the 7 thread cutter and holder showing the parts in different positions;

Fig. 11 is a fragmentary perspective view showing the thread holder;

Fig. 12 is a vertical sectional view on substantially the line 1212, Fig. 1, some of the parts being omitted;

Fig. 13 is a view on the line 13-13, Fig. 12 looking upwardly;

Fig. 14 is a detail of the latch 95.

The thread cutter mechanism embodying my invention may beapplied to various types of sewing machines which are constructed to perform a predetermined sewing operation and then automatically come to rest. As illustrating some sewing machines of this type I would refer to buttonhole sewing machines and so-called tackers which are designed to sew reinforcing stitches such as the barring stitches across the end of the buttonhole or reinforcing stitches or tacks at the corners of pockets and in various other locations in garments.

The sewing machine herein illustrated is of the tacker type, although as stated above, the invention is equally applicable to buttonhole sewing machines and other sewing ma chines that perform a predetermined sewing operation and then come to rest,

Referring to Fig. 1, 1 indicates generally e i ame of a e n hin which is provided with the usual overhanging arm 2 in which reciprocates vertically "the needle bar 3 carrying the upper needle l of the stitch-forming mechanism. The main frame of the sewing machine herein illustrated also provided with the portion 5 on which the work w is supported, this Work being held into engagement.

during the sewing operation by being clamped between an under work clamp 6 and an upper work clamp 7. The complete stitchforming mechanism comprises not only the needle 4 operating from above the work but also suitable mechanism arranged beneath the work and co-operating with the needle 4 to concatinate the stitches.

The stitch-forming mechanism is operated from a power shaft 8 which in turn is driven from a driving pulley 9. This power shaft 8 is geared by gearing to a horizontal shaft 91 extending longitudinally of the arm 2 and by which the needle bar is reciprocated. The shaft 91 in turn is geared by gearing 92 to a vertical cam shaft 93 which carries the cams that control the feeding of the work and the movement of the work clamps for producing the underlying and overlying stitches of a tack or reinforcing seam and other operations.

Inasmuch as the present invention is not concerned with the operative mechanism carried by the shaft 93 I have not deemed it necessary to illustrate it herein but would refer to my co-pending application Serial No. 726,535 as showing more fully such mechanism.

The driving pulley 9 is loosely mounted on the power shaft 8 but is adapted to be clutched thereto by means of any suitable clutch which is actuated by the cone-shaped actuator 10 that is slidably mounted on the shaft. Movement of the clutch actuator 10 toward the left Fig. 2 will throw the clutch into engagement thus clutching the driving pulley 9 to the shaft 8 and movement of the clutch actuator into the position shown in Fig. 2 will release the clutch.

The clutch actuator 10 is given its reciprocating motion on the shaft through the medium of a forked arm 11, the fork of which engages the groove 12 in. the clutch actuator and which extends laterally from the collar fast on clutch-controlling rod 14 that is slidably mounted in the frame and that is acted on by a suitable spring 15 that tends normally to hold it in the position shown in Fig. 2, in which position the clutch is disengaged and the driving pulley 9 is loose on the shaft. lVhen the clutch-control.ling member 14 is moved to the left, thereby compressing the spring 15, such movement will, through the arm 1], shift the clutch actuator 10 to the left and thereby throw the clutch This movement of the clutch-controlling member 14 is secured by an elbow lever 16 pivoted at 17 and one arm of which is connectee by a link 18 to a treadle.

This type of clutch, which forms no part of the present invention, is similar to that illustrated in my Patents No. 1,326,668, December 30, 1919 and No. 1,466,402, August 28, 1923.

Associated with the clutch is a stop motion device for bringing the shaft 8 and stitch forming mechanism to rest at the end of each sewing operation. This stop mechanism comprises a stop cam 19 fast on the shaft 8 and a eo-operating stop dog 20 which is carried in a block or head 21 that is fast on the controlling rod 14. Said stop dog 20 is yieldingly mounted in the block 21 by reason of its being backed by a spring 22.

lVhen the controlling member 14 is moved to the left by the depression of the treadle or otherwise thereby to throw the clutch into engagement this movement will carry the stop dog 20 longitudinally of the shaft 8 and to one side of the path of movement of the stop cam so that the cam is free to rotate while the clutch is in engagement. The controlling rod or member 14 is retained in this position during the sewing operation by means of a latch 94 which is adapted to engage automatically a shoulder 95 on the controlling member when the latter is moved into a position to clutch the driving pulley 9 to the shaft 8 as seen in Fig. 14. This type of latch for holding the clutch in engagement is similar to that more fully illustrated in my co-pending application Serial No. 726,535, filed July 17, 1924.

At the end of the sewing operation the latch is released from the shoulder 95 by means of a cam projection 96 and when the latch is thus released the spring 15, which was con'ipressed by the clutch-engaging movement of the controlling member 14 returns said controlling member to the position shown in Fig. 2 thereby disengaging the clutch and at the same time bringing the deg 20 into the path of movement of the stop cam 19. When this occurs the cam. 19 will engage the end of the dog 20 and the latter will thus bring the shaft 8 to rest, the spring 22 permitting the dog to have a yielding movement so that the stitch-forming mechanism will be brought to rest with a cushioned movement.

The driving and stopping mechanism here in illustrated, therefore, which of itself does not constitute part of my present invention, one in which the driving member (the pulley 9) is a consta11tly-rotating member which is operatively connected to the stitchfol'miug mechanism by means of a clutch.

riccordiug to my present invention the actuation of the thread cutter for trimming the thread at the end of the seam is secured from the constantly-rotating member 9 and said thread cutter is setin operation by the action of the stop motion in bringing the stitch-forming mechanism to rest. For this purpose I have provided an operating cam for actuating the thread cutter. which cam is normally idle, and have provided means for automatically clutching the cam to the constantly-rotating member when the stop motion operates to stop the stitch-forming mechanism whereby the'camwill perform its operation of actuating the cutter and have also provided means for unclutching the cam from the constantly-rotating driving member automatically when the cutter has performed its function.

The thread cutter herein shown is arranged to out the upper thread t which is controlled by the needle 4 and the cutterhas associated therewith a thread holder.

In the operation of the device when asewing operation has been completed the holder will first seize and grip the needle thread and then the cutter will be actuated to cut the thread between the thread holder and the work, the thread holder thus retaining its hold on the end of the thread which extends to the needle. After the next sewing operation has begun the cutteris again actuated to cut the held end of the thread. v

The thread holder is in the form of a finger 24 which is fast on the lower end of a rock shaft 25 which is journalled in a head 26 carried on the end of one of the arms 27 and to which the sections of the upper work clamp 7 are secured, these arms 27 being pivoted at 28 to an upstanding portion 29 of a work clamp supporting member, all as shown in my co-pendi-ng application Serial No. 7 3,7 05, filed December 7 1925.

This rock shaft 25 is acted on by a spring 30 which normally holds it and the finger 24 in the position shown in Fig. 9, in which position said finger is located at one side of the path of movement of the needle 4, the latter passing through the sewing opening 31 at each penetrating thrust. The threadgripping finger 24 is convexly-eurved on one side and concavely-curved on the other, as clearly seen in Figs. 9 to 11. I

At the end of the sewing operation and when the stitch-forming mechanism has been brought to rest with the needle raised the rock shaft 25 is turned to swing the threadgripping finger 24 to the opposite side of the path of movement of the needle into the position shown in Fig. 10, and dotted line Fig. 11, during which movement the convexlycurved side of the finger wipes by the length of thread extending from the needle to the work so that the thread is located on the concavely-curved side of said finger. thread-gripping finger then swings back to its initial position shown in Figs. 11 and l1 and during this movement it engages the thread and pulls its laterally over a clamping plate 32 which is secured to the head 26 andv is situated directly beneath the thread-hold- .ing finger 24. The thread t is thus clamped between the clamping plate 32 and the threadgrippingfinger 24.

After the thread has been clamped itis out between the holding means and the work by a thread cutter in the form of a cutting blade 33 that isprovided with a cutting edge 34. This The.

thread cutter is slidably mounted on the head 26 and operates directly beneath the clamping plate 32. Normally the thread cutter 33 is in its retracted position shown in Fig. 9 in which position the cutting edge 34is situated back of the path of movement of the needle.

As soon-as the thread-holding finger 24 has operated to clamp the thread between itself and the clamping plate 32 the thread cutter 33 is moved forwardly thus bringing the cutting edge 34 against the thread between the holding means and the work thereby cutting the thread close to the work. The cut end leading to the needle will be retained by the thread holder until after the next sewing operation has been started.

' The movements of the thread-holding finger 24 and the thread cutter 33 which are necessary for holding the thread and cutting it are secured by means of an operating cam which is operatively connected automatically to the constantly-rotating member 9 by the operation of the stop motion in bringing the stitch-forming mechanism to rest, said cam becoming automatically disconnected from its driving member after it has performed its function of'holding and cutting the thread and remaining so disconnected until the stop motion againoperates to bring themachineto rest. This cam member. is indicated at 35 and it is shown as mounted on a stud 36 secured to the frame .(see Fig. 5). The camis provided with two cam portions 37 and 38. one of which actuates the thread-holding finger and the other of which actuates the thread cutter. I

The connections by which the thread-holding finger 24 is actuated are as follows. The rock shaft 25 which carries the thread-holding finger 24 has rigid therewith at its upper end an arm 39 from which rises a stud 40 that is received in an open-ended slot 41 formed in the forward end .of a thrust member For rod 42. The rear end of this thrust member or red 42 is pivoted at 43 to an arm 44 that is fast .on a rock shaft 45' journalled in suitable bearings 46 carried by the frame. This shaft 45 has fast thereon a follower arm 47 which is engaged by the cam member 37, said arm being held in engagement with the cam by a spring 48. With this arrangement it will be seen that upon each rotation of the cam 37 the arm 47 will he swung to the left thereby rocking the shaft 45 and swinging the arm 44 to the left, which movement will operate through the thrust rod 42 and arm 39 to turn the rock shaft 25 and thus swing the thread-- holding; arm into the positionshown in Fig. 10. When the cam 37 passes out from under-- neath the arm 47 the threadgripping arm will be returned to its initial; position.

or giving the: cutter its movement I have provided the following. connections. The thread cutter operates between the worl clamping foot 7 and the clampplate 32 and Hill it is formed with an upstanding shank portion 49 which is secured by screws 50 to a sliding head 51 carried by the end of a second thrust member or rod 52. This head 51 is shown as having a guiding slot 53 therein in which is received a guiding stud 54 carried by the head 26. The rear end of the thrust member 52 extends through the upturned end of a rock shaft 56 which is also journaled in the bearing 46, said thrust member 52 having a collar 57 thereon which engages the arm as shown best in Figs. 2 and 4E.

The rock shaft 56 has fast thereon a follower arm 58 which is adapted to be engaged by the cam member 88, said arm being acted on by a spring 59 which holds the arm 58 in engagement with the cam. At each rotation of the cam member 35, therefore, the cam portion 38 will actuate the arm 58 moving it to the left Fig. 1 and thereby turning the rock shaft 56 and operating through the arm 55 to move the thrust rod 52 to the left, this movement giving the cutter its thread-cutting movement as will be understood. lVhen the cam 38 passes out from under the arm 58 the spring 59 will return the parts to their normal position.

The cam 35 is normally inactive or idle and my present invention contemplates means controlled by the stop motion for rendering the cam 35 operative.

hen the cam 35 is being operated it is driven directly from a rotary driving member 60 which is shown as mounted on the stud 36 and which is in turn geared to the driving member 9. This member 60 is in the form of a gear which has gear teeth on its periphery which mesh with a pinion 61 that is loosely mounted on the shaft 8 butis rigid with the driving member 9. For this purpose the driving member has a sleeve 62 rigid therewith through which the shaft 8 extends and on which the clutch-actuator 10 is slidably mounted. This sleeve is provided with a notch 63 in which is received a lug 64 extending from the pinion 61 whereby the pinion is locked to the sleeve and thus is constantly rotating with the driving member 9. Since the pinion 61 is geared to the member 60 said member 60 is also a constantly rotating mem bar.

A clutch is provided for clutching the cam member 35 to the rotating member 60 at the time that the thread holder and cutter are to be actuated. This clutch is herein shown as a clutch pin 64 slidably mounted in the cam member 35 and acted on by a spring 65 tending to throw it into clutching engagement with the rotating member 60, the latter having one or more recesses 66 to receive the pin as shown in Fig. 5. This pin is provided with a head 67 and normally it is held in its retracted position shown in dotted lines Fig. 5 by means of a clutch dog 68 which is in the form of an arm carried by a rock shaft 69 that is also journalled in the bearing 46. The rock shaft 69 is acted on by a spring '70 which tends to hold the clutch dog in the operative position shown in full lines Fig. 1.

l/Vhen the clutch is disengaged the clutch dog is in its operative position and the head 67 of the clutch pin is engaging the dog and is held in its retracted position shown in dotted lines Fig. 5 and out of clutching engagement with the member 60. When, however, the clutch dog is swung backwardly so as to withdraw it from engagement with the head 67 of the clutch pin then the spring 65 will throw the clutch pin forwardly into clutching engagement with the constantly-rotating member 60 thus coupling the cam to said member. This operation of throwing the clutch into engagement is derived from the action of the stop motion so that the operation of bringing the stitch-forming mechanism to rest will result in clutching the cam 35 to the rotating member 60.

The block 21 of the stop motion is provi .ed with an upstanding finger 71 which has engagement with an arm 72 rigid with the roclr shaft 69. When the stop motion operates to bring the stitch-forming mechanism to rest the action of the stop cam 19 on the stop dog 20 will not only force the stop dog 20 downwardly in Fig. 3 against the action of the spring 22 but will also give the bloclr 21 a slight rocking movement toward the right Fig. 3 thus momentarily swinging the [in 'er 71 into the dotted line position. This iii k 71 has a return spring 73 connected thereto so'that it will immediately be returned to its normal position. The sto pi if the stitchforming mechanism, however, will re a quick momentary movement of the r 71 into the dotted line position Fig. 3. Dan ing this movement the finger 71 acts on the arm 72 to rock the shaft 69 and. thereby raise the clutch dog (38 out of engagement with the head 67 of the clutch pin. This will allow the clutch pin to clutch the ram to the member 60 so that said cam will be rotated by the member 60.

Since the movement of the ling \r it a momentary movement only the reel: r 69 will imn'icdiately return to its normal position through the influence of the spring so that as the cam member 35 completes its first rotation the head 67 of the clutch pin will engage the inclined face 75 of the clutch dog and will thus be withdrawn from clutch ing engagement with the member 60. clutch, therefore, by which the cam 35 is open ated, is a one-revolution clutch. it is thrown into clutching engagement by m ans (This trolled by the stop motion and it is automaticallythrown out of clutching engagement upon the completion of onerevolution.

The means above described are for holding and trimming the thread at the end of sewing operation, the thread being cut Th is iii;

tween the thread holder and the work. The thread holder continues its hold on the thread until the next sewing operation has begun thereby to trim the held end of the thread. This means for trimming at the beginning of the sewing operation is illustrated in Fig. 4'.

The cam shaft 93 has thereon a cam member 76 which makes one rotationduring each sewing operation. This cam member is provided with a cam projection 77 which cooperates with an elbow lever 78 pivoted to the frame at 79. When the sewing machine is started in operation the rotationof themen'n ber 76 will cause the cainproj'ection 77 to engage the a H1 80 at a period of time after the stitching operation has begun thereby giving the elbow lever 78 a swinging movement. The arm 81 of this elbow lever 78 is situated to engage the end of the thrust rod 52 by which the cutter is actuated and, therefore, after any stitching has begun the push rod 52 will be actuated thus operating the cutter 33 to cut the thread between the holding means and the work, thus trimming the thread close to the work. This movement of the push rod 52 is permitted without being interfered with by the arm 55. by reason of the fact that the push rod extends freely through the upper end of said arm. Said push rod, therefore, is adapted to be actuated either by the arm 55. or by the lever 78. The arm 55 operates the. push rod 52 at the end of the seam and the, lever 78 operates it at the beginning of the seam. V

' In-the construction herein shown the work clamps are raised manually by means of alever 89 pivoted to the arm at 88 and having a link 87 connected thereto at one end which leads to. a treadle, the other end of the lever carrying a lifting member 86 adaptedto engage thearms 27 when the treadle is depressed thereby to raise the clamps.

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

I claim:

1. In. a sewing machine, the combination with stitch-forming mechanism, of means for operating said, stitch-forming mechanism, a stop motion device to bring the stitch-forming mechanism to rest, which stop motion 111- cludes a stop cam and a yieldingly mounted stop dog which has a yieldingmovement when engaged by the stop cam to bring themachine to rest, awthread trimmer, means set in operation by the yielding motion of the stop dog to actuate the thread trimmer after the stitchforming mechanism has come to rest, and other means to actuate said thread trimmer after the stitch-forming mechanism has started. r

2. In a sewing machine, the combination with stitch-formingmechanism, of operating means therefor, a stop motion device to bring with stitch-forming mechanism, of a stop motion device to bring the stitch-forming mechanism torest, which stop motion includes a stop cam and a yieldingly mounted stop dog which has a yielding movement when engaged by the stop cam to bring the machine to rest, a thread trimmer, a thread holder, means set in operation bythe yielding motion of the stop dog to cause actuation of both the thread trimmer and the thread holder after the stitch-forming mechanism has come to rest, and means to actuate said thread trimmer at the beginning of each sewing operation.

4. In a sewingmachine, the combination with stitch-forming mechanism, of a stop mechanism torest, which stop motion includes a stop cam and ,a -yieldingly mounted stop dog which has a yielding movement when engaged by the stop cam to bring the machine to rest, a thread trimmer, a thread holder, means setin operation by the yielding motion of the stop dog to. cause actuation of both the thread trimmer and the thread holder after the stitch-forming.meehanism has come to rest, and means to actuate said thread trimmer only at thebeginning of the sewing operation; H v

5. In a sewing machine, t-he combination with stitch-forming mechanism, of operating means therefor, a stop motion device to bring the stitch-forming mechanism to rest, which stopmotion includes a stop cam and a yieldingly mounted stop dog which has a yielding motion device to bring the stitch-forming" movement when engaged by the stop cam to bring the machine to rest, thread. trimmer,

a thread holder, means set in operation by the yieldingmotionof the stop dog to cause actuation ofboth the thread trimmer and said thread holder, and, means to actuate the thread trimmer atthe beginning of the seam -by the operating means for the stitch-form ing mechanism;

6. In a sewing machine, the combination with stitch-forming mechanism, of operating means therefor, a stop motion device to bring the stitch-forming mechanism to rest, which stopmotion includes a stopcam and a yieldingly mounted stop dog. which has a yielding movement when engaged by the stop cam to bringthe machine to, rest, arthread trimmer, a thread holder, means set in operation by the yielding movement of the stop dog to cause actuation of the thread trimmer and the thread holder after the stitch-forming mechanism has come to rest, and means to actuate said thread trimmer at the beginning of the seam by the operating means for the stitchi orming mechanism.

7. In a sewing machine, the combination with stitch-forming mechanism including a. needle operating from above the work, of a constantly-rotating driving member, a clutch for driving the stitch-forming mechanism from the driving member, a stop motion device to disengage the clutch and bring the stitch-:t'orming mechanism to rest at the end of a seam, and means to trim the needle thread above the work, said means being controlled by the stop motion and deriving its threadcutting movement from the driving member.

8. In a sewing machine, the combination with stitclrtorming mechanism, including a needle operating from above the Work, of a constantly-rotating driving member, a clutch for driving the stitch-forming mechanism from the driving member, a stop motion device to disengage the clutch and bring the stitch-forming mechanism to rest at the end of a seam, and means controlled by the stop motion but deriving its thread-cutting movement from the driving member to trim the needle thread above the Work after the stitchlormin mechanism has come to rest.

9. In a sewing machine, the combination with stitch forming mechanism, of a constantly-rotating driving member, a clutch for driving the stitch-forming mechanism from the driving member, a stop motion device to disengage the clutch and bring the stitchforming mechanism to rest at the end of a seam, means to grip and hold the thread and means controlled by the stop motion but deriving its thread-cutting movement from the driving member to cut the thread between the holding means and the Work.

10. In a sewing machine, the combination with stitcl1ingforn1ing mechanism, of a constantly-rotating driving member, a clutch for driving the stitch-forming mechanism from the dri ing member, a stop motion device to dis ngagc the clutch and bring the stitchtorming mechanism to rest at the end of a seam, means controlled by the stop motion but actuated by the driving member after the stitch-forming mechanism has come to rest to seize and hold the thread and then to cut the thread between the holding means and the work.

11. In a sewing machine, the combination with stitch-forming mechanism including a needle penetrating the work from above, of operating means therefor, a stop motion de vice to bring the stitch-forming mechanism to rest, which stop motion includes a stop cam and a yieldin l'y mounted stop dog which has a yielding movement when engaged by the stop cam to bring the machine to rest,means to seize and hold the needle thread above the work, a thread trimmer to out the thread between the holding means and the work, and means set in operation by the yielding move ment of the stop dog to cause actuation of the thread trimmer and thread holder after the stitch-forming mechanism has come to rest, and other means to actuate the thread trimmer after the next stitching operation h as started.

12. In a sewing machine, the combination with stitching-forming mechanism, a con stantly-rotating driving member, a clutch for driving said stitch-forming mechanism from the driving member, a stop motion device to disengage the clutch and bring the stitcht'orming mechanism to rest at the end of the seam, means to seize and hold the thread, a thread trimmer for cutting the thread between the holding means and the work, and means controlled by the stop motion but actuated by said driving member for actuating the thread holder and the thread trimmer at the end of the seam, and means to actuate the thread trimmer at the beginning of the seam.

13. In a sewing machine, the combination with stitch-forming mechanism, of a stop motion device for bringing the stitch-forming mechanism to rest at the end of the sewing operation, a constantly-rotating member a thread trimmer, and means controlled by the stop motion but actuated by the constantly rotating member to operate the thread trimmer to cut the thread after the stitchforming mechanism has been brought to rest and other means to operate said thread trimmer at the beginning of the sewing operation.

14. In a sewing machine, the combination with stitch-forming mechanism, of a stop motion device for bringing the stitch-forming mechanism to rest at the end of the sewing operation, a constantly-rotating member, a thread trimmer, means controlled by the stop motion but actuated by the constantlyrotating member to seize and hold the thread after the stitch-forming mechanism stops and then to actuate the thread trimmer to cut the thread at the end of the sewing operation, and other means to actuate the trimmer at the bcginning of the sewing operation.

In a sewing machine, he combination with stitch-forming mechanism, of operating means therefor, a stop motion device for bringing the stitch-im'ming mechanism to at the end of a sewing operation, a constantly-rotating member, a thread holder, a thread cutter, means coi'itrolled by the stop motion but actuated by the constantly-rotating member to actuate the thread holder and the thread cutter after the stitch-forming mechanism has come to rest, and other means to actuate the cutter at the beginning of the sewing operation.

16. In a sewing machine, the combination with stitch-forming mechanism, of operating means therefor, a stop motion device for bringing the stitch-forming mechanism to rest at the end of a sewing operation, a constantly-rotating member, a thread holder, and a thread cutter, means controlled by the stop motion but actuated by the constantlyrotating member to actuate the thread holder and the thread cutter ater the stitch-forming mechanism has come to rest, and means to actuate the thread cutter at the beginning of the sewing operation.

17. In a sewing machine, the combination with stitch-forming mechanism, of operat ing means therefor, a constantly-rotating member, a thread trimmer, a cam for actuating the thread trimmer, normally disconnectcd from the constantly-rotating member, a stop motion for bringing the stitch-forming mechanism to rest, which stop motion includes a stop cam and a yieldingly mounted stop dog which has a yieldingmovement when engaged by the stop cam to bring the machine to rest and means actuated by the yielding movement of the stop dog to connect said cam to the constantly-rotating member whereb the trimmer is operated. V

18. In a sewing machine, the combination with stitch-forming mechanism, of operating means therefor, a stop motion for bringing the stitch-forming mechanism'to rest, which stop motion includes a stop cam and a yieldingly mounted stop dog which has a yielding movement when engaged by the stop cam to bring the machine to rest, a thread trimmer, a thread holder, a constantly-rotatitng member, a cam device for actuating the thread holder and giving the thread trimmer its thread cutting movement, which cam is inoperative during the sewing operation, a onerevolution clutch for connecting the cam to theconstantly-rotating member, and means set in operation by the yielding motion of the stop dog to throw said clutch into engagement. I i

19. In a sewing machine, the combination with stitchfo 'ming mechanism, of means for operating said stitch-forming mechanism, a stop motion device to bring the stitch-forming mechanism to rest, which stop motion device includes a stop cam and a yieldingly mounted stop dog which has a yielding move-.

ment when engaged by the stop cam to bring the machine to rest, 'a thread trimmer, and means set in operation by the yielding motion of the stop dog to actuate the thread trimmer after the stitch-forming mechanism has come to rest.

20. In a sewing machine, the combination w'th stitch-forming mechanism, of means for operating said stitch-forming mechanism, a stop motion device to bring the stitch-forming mechanism to rest, which stop motion device includes a stop cam and a yieldingly mounted stop dog which has a yielding movement JOHN KIEWICZ Hit)

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