US2621620A - Needle dipper mechanism - Google Patents

Description

Dec. 16, 1952 F. CHATF'I'ELD ETAL I NEEDLE DIPPER MECHANISM Filed May 9. 1949 MACHINE STO PPED G. 2

BRAKE ON CLUTCH 'DISENGAGE FOR NEEDLE DIPPING I M'AGHINE RUNNING 9 Sheets-Sheet l BRAKE OFF CLUTCH ENGAGED BRAKE OFF CLUTCH ENGAGED 23 l' l r I 1 a; 64 f 2z E N sAFETYsToP 1 F SOLENOID J3 1 %L"" j CLUTCH 'DISENGAGED 48 49 3 6 zsma amm FOR NEEDLE DIPPING 7/ #47 35 {I MACHINE RUNNING SOLENOID M 66 INVENTORS FRANKLIN CHATF/ELD STANLEY FP. FOLSOM ATTORNE Y5 Dec. 16, 1952 F. CHATFIELD ETAL 2,621,620

- NEEDLE pIPPER MECHANISM Fi led May 9, 1949 9 Sheets- Sheet 2 1N VEN TORS F RANKLIN CHATFYELD STANLEY F. Fogso/ r I 2/0 f l,

ATTomswg Dec. 16, 1952 Filed May 9. 1949 MACHINE STOPPED F. CHATFIELD ETAL 2,621,620

NEEDLE DIPPER MECHANISM 9 Shets-Sheet I5 MACHINE RUNNING .BRAKE oN BRAKE on 49 CLUTCH msENGAGEB C CH ENGAGED J i i 3 f 7/ "H l *1 e0 6' 76 E 6/ a BRAKE OFF CLUTCH DISENGAGED J9 FOR NEEDLE DIPPING sAFE-rY. STOP SOLENOID 3/ MACHINE STOPPED l 3 BRAKE 0N 6 CLUTCH DISENGAG7E2D G 8 {-49 3 BRAKE OFF 7/ 7 CLUTCH DISENGAGED 35 FOR NEEDLE DIPPING 38 3f 47 5/ MACHINE RuNNlNG J9 BRAKE OFF 4O CLUTCH ENGAGED a BRAKE RELEASE 0 SOLENOID %4, WMG M ATTORNEYS 1952 F. CHATFIELD ETAL 2,621,620

NEEDLE DIPPER MECHANISM 9 Sheets-Sheet 4 Filed May 9, 1949 X K, /6.9-'l l SAFETY STOP BRAKE RELEASE SOLENOID SOLENOID lea mmvrozas FRANKLIN CHATF'IELD STANLEY P. FOLSOM TTOR/VEYS Dec. 16, 1952 Filed May 9. 1949 F. CHATFIELD ETAL NEEDLE DIPPER MECHANISM 9 Sheets-Sheet 5 INVENTORS FRANKLIN CHATF/E'LD STANLEY R FOLSOM MmM WM ATTORNEYS Dec. 16, 1952 F. CHATFlELD ETAL 2,621,520

NEEDLE DIPPER MECHANISM Filed May 9, 1949 9 Sheets-Sheet 6 IDLE FORWARD RUN TO ENGAGE [40 WITH SURFACE IIB ON CAM H5 .l 7 7.5

FORWARD I46 REVERSE M I I STITCH PARTIALLY COMPLETED H AND BEYOND UNLOCKINC v F6 v POSITION ORIGINAL STITCH COMPLETED FORWARD REVgRSE PlN |4| BEGINS v0 ENGAGE CAM I45 28B STITCH STARTED m3 FIG.|5 -75 POSITION FIG. I3 POSITION H6. l6 5 He. /4

FORV'KARD 3? REVERSE /7 /o'o., I

l3! [Ficus POSITION M7 M0 /63 COAST A no. POSITION 2 u I POSITJON WHEN 75 [7 F PIN: MOV s up f; Ms E 1:19 ,7 INVENTORS ENOUGH To F QANKL/N CHATFIELD RELEASE I40 A V Z STITCH CARRIED FORWARD o FR BUT IS STOPPED SHORT 0F W UNLOCKING CONDITION M 4 A I t 1 ATTORNEYS Dec. 16, '1952 F. CHATFIELD ETAL 2,621,620

NEEDLE DIPPER MECHANISM Filed May 9, 1949 9 Sheets-Sheet 7 FORWARD REVERSE IDLE REVERSE RUN 75 OF PIN I40 BEFORE IT ENGAGES BACK SURFACE "7 ON CAM NO MOVEMENT OF SEWING MACHINE ON BACK RUN I g A20 PIN |4I BEGINS TO ENGAGE CAM I46 FORWARD REvERsE h FIG.2| POSITION lg? /00 L85 REVERSRUN M9 OF SEWING A25 MACHINE UN- FORMED (CAST OFF) PARTIALLY FORMED Z STITC H Fis.2/

F1623 POSITION FORWAQRD COAST REVER\SE FIG.2| I35 POSITION I A /o IV J I17 Z'QSTITCH COMPLETELY CAST OFF IN VEN TORS AND NEEDLE BAR RAISED To FULL FRANKL/N CHAT/WELD UP POSITION S NLEY FOLSOM fml,

ATTORNEYS Dec. 16, 1952 F. CHATFIELD ETAL NEEDLE DIPPER MECI-IANISIII' Filed May 9. 1949 REVERSE FORWARD STITCH JUST STARTED BUT HAS NOT REACH POINT JUST SHORT OF LOCKING FORWARD REVERSE mu: RUN .wrm PIN 141 suomc AGAINST OUTERFACE OF cmus 1 9 Sheets-Sheet 8 CAM AND SEWING MACHINE REMAIN FIG. 25 POSITION II! I CAM AND SEWING rMACHINE REMAIN 9 IN FIG-25 PO/SITION I I I I I FURTHER IDLE RUN OF PIN I40 UNTIL IT ENGAGES SURFACE "8 OF CAM II5 AS IN FIGS.I4-l5. FROM THEN ON SEQUENCE AS IN FIGS. l4-23 INVENTORS FRANKLIN CHATF'IELD STANLEY R FOLSOM A T'TORNE vs Patented Dec. 16, 1952 NEEDLE DIPPER MECHANISM Franklin Chatfield and Stanley Roberts Folsom,

Minneapolis, Minn, assignors to Munsingwear, Inc., Minneapolis, Minn., a corporation of Delaware application May 9, 1949, Serial No. 92,182

11 Claims.

This invention relates to devices for use in conjunction with sewing machines and more particularly for use with power driven production sewing machines. In the operation .oi such sewing machines, of which there are many varieties, stitch formation is accomplished by the interaction of the needle thread (or m-ultiple'needle threads) with another stitch forming device which may or may not carry another thread or threads. The device which cooperates with the needle to form the stitch may be a shuttle, but in most machines is a looper bar mechanism or multiple looper bar mechanism.

The instant invention is for use with sewing machines of such types. In general, it may be stated that the instant invention is used in cenjunction with chain or look stitch sewing machines, such as one, two, three or higher multiple needle machines having single, .d'oiiblefor triple interlock; fiat lock machines; multiple needle machines using lower or upp'ei'and lowerlooper mechanism; one, two or three needle triple'interlock machines and the like. It is to be understood that this is by no means a complete list of types of sewing machines to which the invention is applicable.

During the operation of such sewing machines as, for example, at the end of a stitched seam, the operator of the machinemay desire to withdraw the work and this necessitates drawing off the threads from the needle or needles and'also in many machines requires the simultaneous withdrawal of thread from theshuttle or looper mechanisms, so as to allow cutting the threads beyond the termination of stitching. This provides suitable length of threads extending from the machine preparatory to insertion of more work and allows the thread or threads toextend beyond the line of stitches just formed. To permit such withdrawal of the thread or threads, which in every case must run smoothlyand simultaneously through the eye of the needle -(or;needles) and where the shuttle or looper mechanisms carry thread also throughthe eye or eyes of the shuttle or looper mechanisms, it is necessary to have completedthe last stitch andpto have the needle (needle bar) retracted from the work (up position) and in a prescribed position so that the thread tension mechanisms will release .all threads and permit them to be drawn out smoothly. In the simplest sewing machines, namely those of the household type a considerable range of angular movement of the sewing machine drive shaft and corresponding considerable range of movement of the needle before and after reaching retracted (up) position, is "possible andthe operator can usually obtain a condition of release of the threadsby bringingftheneedle 'toward and past the up.posi't ion and fthenffeel for the release position by rotatingthe hand wheel forwardly and reversely while applying slight tension to the work until the threads release and run free. However, in many precision machines, particularly the more complex production machines, a prescribed sequence of opera tions must be followed to obtain such release of the threads. This sequence of operation is known in'the textile arts as needle dipping and is as followsi When the line of stitching is to be completed, the operator brings the sewing machine controls to the stopping position and the sewing machine therefore stops, but the position of the needle bar and needles carried thereby may be at any place throughout the range of movements of these devices during stitch formation, and thus may be completely down with the needles completely penetrating the work or entirely retracted (up) with the needles completely withdrawn from the work, or at any place between these e;; tremes on either the downstroke or the upstroke of the needle bar. The stopping position is a random occurrence and the operator has no way of predetermining the stopping position. Accordingly, the sewing machine may come to rest with the stitch in any degree of formation. It should be borne in mind that throughout the sequence of occurrences in stitch formation, the same things do not happen on the upstroke of the needle as happen on the downstroke of the needle. Furthermore, stitch formation is not a reversible process, i. e. the thread cannot be unstitched by reversing direction of running of the sewing machine, except that during the formation of the stitch and up to a certain point in stitch formation, which is before the threads lock, revers ing direction of the sewing machine will permit the partly formed stitch to be cast off.

In the sequence of needle dipping the operator takes ahold of the sewing machine hand wheel after it has come to rest and then propels it slowly by hand in the stitch-forming direction until the stitch which is in the process of being made is completed and the process of formation of the next stitch is begunandcarried to a point just short of locking the stitch. Then the direction of rotation of the hand wheel is reversed and it is backed until the needles (needle bar) are at the retracted (up) position. When this is done the threads of any machine will be released and (provided the presser foot is raised) the material can be withdrawn and the thread or threads, of which the line of stitches were formed, will be withdrawn easily (and if several threads are involved, simultaneously) through the eyes of the needle (or needles) and the eyes of the bobbin or looper bar or bars .or other stitch-forming mechanisms, in the event these carry threads.

It may be noted parentheticall that, dependin upon the design of the machine, the direction of rotation of the hand wheel may be in either direction when the machine is running in the stitch-forming direction. Thus, in some machines the top of the hand wheel moves towards the operator while forming the stitches, whereas in others the top of the hand wheel moves away from the operator when the machine is running in stitch-forming direction. Throughout this specification movement of the machine mechanism in stitch-forming direction will be designated the forward direction, regardless of whether the top of the hand wheel runs towards or away from the operator, whereas movement opposite to the stitch-forming direction Will be called reverse direction.

Using this nomenclature, the process of needle dipping is (l) to stop the machine, (2) to propel the machine by hand in the forward direction until the partially formed stitch is completed and the next stitch is partly completed, to a condition short of that point in the stitch formation where the threads look, i. e. can be cast off and the partially formed stitch uh-formed and (3) to then propel the machine by hand in a reverse direction until the needle bar is completely retracted (up) which has the efiect of unforming the last partially formed stitch. When this is done, and regardless of the particular style of stitch, the threads will be released and (provided the presser foot is raised) the work can be pulled out and thread or threads running through the stitch-forming mechanism will run freely and can be extended indefinitely (drawn out) to any desired length.

The process of needle dipping, While seemingly very simple, is actually difficult to achieve in production machines because of the fact that production machines are motor driven and stopped by brakes. As a result of this it takes weeks and even months for an operator to learn to put this needle dipping technique into practice, and some operators never learn the technique. The reason is that the modern production sewing machine is a high speed precision instrument, and requires precise control and is driven and stopped by a treadle mechanism which controls the running of the machine through a clutch on a high speed constantly running motor and controls the stopping by means of clutch release and brake. Thus, usually, the drive consists of a powerful high-speed, constantly-running motor (or line shaft) connected through a combined clutch-brake mechanism to the sewing machine drive wheel, the clutch-brake mechanism being connected to a foot treadle so that when the treadle is pushed forwardly (toe down, heel up) the brake goes off and the clutch is engaged to run the machine; when the treadle is centered (placed neutral, i. e. equal pressure on toe or heel) the brake goes off and the clutch is released and when the treadle is moved backwardly (heel down, toe up), the clutch is disengaged and the brake is applied.

These three positions of the treadle (i. e. run, neutral and stop) are set close and the neutral position (clutch disengaged, brake off) is hence closely prescribed. If the treadle is pushed forwardly (toe down) from neutral, the machine will begin to run and if the treadle is pushed heel down from neutral the brake is set and the machine cannot be turned even by hand. While it would be possible to adjust the treadle so as to give a broad neutral range, this is undesirable because the machine should 4 always be under precise control (i. e. should either run or stop and should not coast) and also because for best production the treadle controls should be set sensitive and responsive to slight movements of the operators foot.

These facts concerning the power drive and controls have their efiect upon the needle dipping sequence for the needle dipping is carried out by propelling the machine by hand; hence, it can only be done when the machine controls are in neutral, i. e. clutch disengaged and brake off. Therefore, to carry out the needle dipping sequence on power driven machines the operator must first learn to position the controls in neutral and then carry out the needle dipping sequence. This is difiicult to do.

It is an object of the present invention to provide a needle dipper mechanism and more particularly to provide a mechanism for carrying out the needle dipping function automatically.

It is also an object of the invention to provide a mechanism for carrying out the needle dipping sequence on power driven sewing machines,

It is a further object of the invention to provide an operator controlled mechanism for power driven sewing machines having a single operator control for automatically placing the machine in neutral and then carrying out the needle dipping sequence, and to provide such a mechanism in which provision is made for guarding against power drive of the sewing machine during the needle dipping sequence.

It is another object of the invention to pro vide an operator controlled mechanism for ac complishing needle dipping with power and also to provide an operator controlled mechanism for carrying out the sequence of needle dipping on any sewing machine.

Other objects of the invention are those inherent in the apparatus herein illustrated, described and claimed.

The invention is illustrated with reference to the drawings in which corresponding numerals refer to the same parts and in which Figure 1 is a front elevational view of the usual form of production type power-driven sewing machine with which the apparatus of the invention is incorporated;

Figure 2 is an enlarged fragmentary front elevational view of a portion of the control mechanism of the instant invention;

Figure 3 is a front elevational view of the sewing machine illustrated in Figure l, to which the invention is applied, showing the operating parts in another position;

Figure 4 is an enlarged front elevational view of a portion of the apparatus of Figure 3;

Figure 5 is a transverse sectional view taken in the direction of arrows 5-5 of Figure 1 showing a portion of the needle dipping mechanism;

Figure 6 is a plan view of the apparatus shown in Figure 5 and is taken along the lines 6-6 of Figure 5;

Figure 7 is a wiring diagram of certain of the electrical components of the invention, together with certain of the mechanical components thereof;

Figure 8 is a vertical sectional view of a portion of the mechanism shown in Figures 5 and 6, taken in the direction of arrows and along the line 88 of Figures 5 and 6;

Figure 9 corresponds to the apparatus shown in Figure 8, except that it is a fragmentary vertical elevational view in the direction of and along the line 9-9 of Figure 6;

t Figure 101s a plan view of the portion bf-th apparatus shown in Figures 8 and 9 andis taken along-the line and in the direction of arrows Iii-l of Figure M Figure 11 is a side elevational view partly in section taken along the line-and inthedire'ction ofarrows' H'-+ll of Figures 8, 9 and 10.

The series of views Figures 12-29 aresh'own in corresponding pairs. Thus, Figures 12 and 13 correspond; Figures 14 and15 correspond and so forth through this series. Throughout this series the even-numbered views, viz. Figures 12, 14", 16 etc. to Figure 28 correspond to Figure 10, being a fragmentary top plan view taken along the line andin the direction of arrows lB--l0 of Figure 5, whereas the odd-numbered Figures13, 15, 17 etc. through Figure 23 correspond to Figure '11. This series of views, Figures 12-13, Figures 14-15, Figures 16-17 and so on through Figures 22-23 illustrate certain of the working parts. of the needle dipper throughout the series of positions through which the parts move during the needle dipping operation for various positions in which thesewing machine. has stopped prior to the needle dipping operation. As further explanation, it is noted that Figure 13 is a sectional view in elevation, taken along the line. l3-l3 of Figure. 12. Figure 15 is a sectional view in elevation taken along the line Iii-l5 of Figure. 14. Figure 17 is an elevational view partly in section taken along. the line and in the direction of arrows l.1.-I1 of Figure 16. Figure 19 is an elevational .view partly in section taken alongthe lineand in the direction of arrows l9-l9 of Figure 18. Figure.21 is a sectional view partly in elevation taken along the line and in the direction of arrows 2l2l of Figure 20. Figure 23 is a sectional view partly in elevation taken along the line and in the direction of arrows 23-23 of Figure 22. Figure is a sectional view partly in "elevation taken along the line and in the direction of arrows 25-25 of Figure 24. Figure-27 isa sectional View in elevation taken along the line and in the direction of arrows 27-2| of Figure'26. Figure 29 is a sectional view in elevation'taken along the line and in the direction of arrows '2329 of Figure 28.

Figure is a side sectional view corresponding to Figure 5, except that it is fora sewing machine which is driven in the opposite direction of rotation for stitch formation than that in Figure 5. Figure 30 is taken alongthesame section line as shown at line 55 of Figure 1. Figure 31 is a plan view with the cover removed, of the apparatus shown in Figure30, and istaken along the line and in the direction of arrows 3|3l of Figure 30.

Figures 32 and 33 show a somewhat modified form of adjustable cam for the needle dipping mechanism, Figure 32 being anelevational view partly in section and Figure 33 being a fragmentary side view taken along'the line andin'the direction of arrows 33-33 of Figure 32.

Referring to the'drawings'and particularly to Figures 1-9 the apparatus is illustrated as applied to a conventional power-driven production. type sewing machine generally designatedlowhich includes a frame I i, work plate l2,-needle bar I3, a needle operating mechanism l5,various thread guides and threadtension mechanisms I6, I! and the like and a main sewing machine drive shaft I8 ,;which isprovidedwith a hand wheell9; This particular sewingmachine, which it must beunderstood is illustrativeof many types to which the" invention "is applicable, is: of the-:type whichrotates in the directionof arrow 20 when moving iii-the stitch forming direction, that is to say the top of the hand wheel l9 movesaway from the front of the machine (operator station) when'the machine is moving in the stitch-forming direc; tion. The hand wheel I9 is provided witha V-pulley at 21 in which a 'v belt 22 or other suitable drive belt runs. The entire sewing machine (sewing head) is mounted-upon the board 23 which is supported by legs 24-, 25 that are in turn tied together by the bottom cr'o's's braces 2'5 and 21. V

Beneath th'e'sewi'ng head Ill and fastened to the under side of the board 23v there is a constantly running motor 2.8 which in some machines is replaced by a line shaft. The support for the motor is by means of pedestal 29 reaching u'pto and fastened to the board 23. The motor 231s of the constantly rotating type and is pr'ovidedat one end with a combined clutch-brake m'echa nism 38, by means of which the rotation of "the motor may be communicated to the drive shaft 31 and to the drive pulley 32 over which the V belt 22 also travels so 'th'atwv' hen the pulley 321s driven by the motor, the belt 22 will travelin'the direction 'of the arrow 33 and drive the hand wheel ['9 and shaft [3: of the sewing machine in the stitch-forming direction.

The clutch-brake mechanism 33', which per se forms no part of the instant invention, is arranged to be actuated by means of a lever '35 pivotally mounted at pin -36 on brackett'l, which is a part of the motor. The lver 3'5-ha s'a bend in it and extends across below themotor at the portion 35' and nea'rits outer end is provided with a pin 38 to which the upperend of-a tension spring 40 is attached, the lower end-of the'sp'ring so being connected to the eye 41 inthe upper end of a pull rod 42 that'extendsdowntoand'is pivotally attached to the rear part offa treadle 43, the latter being pivotally m'ounted'at 44 and 44' upon the bottom cross brace 21. The treadle 43 when moved tothe forward'position (toe down, heel up) causes therod 42 to be pulled downwardly in the direction of arrow '45 and-consequently the lever 35 is pulled downwardly 'inth'e direction of arrow 41 and pivots about the'p'in 36 and in this position causes the brake to be disengaged and the clutch to be engaged, thus allowing the motor 28 to drive the shaft 31 and pulley 32 in a clockwise direction as viewed from the right end, or stated another way, in the direction to move the front side of the belt'22 -upwardly in the direction of arrows '33} The sewing machine I0 is accordingly driven in the stitch-forming direction.

When the operator releases the toedow'n, -heel up pressure on the treadle d3, thedowriward pull on the rod 42 is released and'the lever '35 is moved upwardly by meansof a spring 4'8'connected between the lever 35- andthe moter 28. The spring 48 causesthelever35- to 'move upwardly in the-direction of arrow 49 and therefore moves the lever about the pivot pin 35 through the neutral position where'the clutch is disengaged and thebrake not yet'eng'aged, and into the braking position where the clutch" isdisengaged and the brake is engaged. When this occurs, a braking force is appliedto the shaftSI and hence to the pully 32, and this brakingforce is communicated through'the belt 22 to the drive shaft [8 of the sewing machine, causingthe latter quickly to come to a stop and to be held immovably. This is the-customary type ofrproduction-g sewing machine'control. -It mayalsobe noted that upon the bottom cross brace 21 there is also mounted a supplemental treadle 50 which is connected through the chain to the free end of the lever 52 that serves to raise or lower the presser foot of the sewing machine. These latter elements are illustrated and herein mentioned merely as showing the customary type of sewing machine auxiliary mechanisms.

In accordance with the instant invention the lever 35 is provided with supplementary solenoid actuated mechanism by which the lever can be positively moved to the neutral (clutch disengaged-brake not engaged) position, but held against movement beyond the neutral position to the running position where the clutch would be engaged. These supplemental mechanisms take the form of a pair of solenoids which are best illustrated in Figures 1-4. One of these solenoids, namely the brake release solenoid 55, is provided with a winding served by a pair of conductors 55 and has an armature 58 which is pulled upwardly by lever 35 due to the action of spring 48. When pin 69 on lever 35 reaches end 63 of slot 6!, the link 59 and armature 58 are lifted. The armature 58 is pulled downwardly by the magnetic action of the solenoid. The armature 58 is coupled by means of a link 59 to a pin 55 set crosswise in the motor control lever 35. The member 59 has a slot Bl in it which has a length extending from the line 62 to the line 53, Figure 2. The length of the slot 6| is such that when the solenoid 55 is energized the upper end of the slot at the line 63 will engage upon the pin 60 set in the lever 35 and will pull the pin, and hence the lever, to the neutral position shown in full lines in Figure 4. However, the length of the slot 5| is such that when the solenoid 55 is de-energized and the link 59 hence is moved to the position shown in Figures 1 and 2, the operator can, by moving the treadle 43, cause the lever 35 to move beyond the neutral position and into the running position (denoted Machine Running Brake Ofi Clutch Engaged) in Figures 1 and 3 and shown by the lower dotted lines in these figures. Thus, the action of brake release solenoid 55 is such that when energized it will, through the link 59 and slot GI and pin 65, cause the lever 35 to be drawn down to the neutral position. The movement of the solenoid 55 is a very rapid, snap action movement and accordingly when the armature 58 thus moves rapidly downwardly when the solenoid is energized, it produces a quick downward pull on the link 59 and this causes the lever 35 likewise to be pulled down rapidly. The fact that slot 5| extends downwardly far below the pin 50 when in the full line position shown in Figure 4 would permit the lever 35 when pulled by armature 58 to move downwardly and then by inertia to move beyond the neutral position, and hence into the position where the brake is off and the clutch is engaged (shown by the lower dotted line position in Figure 2) and hence the machine would tend to start and run a little bit which is undesirable. In order to prevent this from happening there is provided a safety solenoid generally designated 65 which is energized through a pair of conductors 64.

The safety solenoid armature 65 of the solenoid 55 normally moves downwardly under its own weight and is lifted upwardly when the solenoid 55 is energized. The armature 65 is connected pivotally at 6! to the link 58 which, at its lower end, is slotted from the position 69 to the position'lll, the slot being designated H. The slot H serves as a connection to a pin 12 set crosswise through the end of the lever 35 of the motor control mechanism. It is the purpose of the safety solenoid and the link connection 68 through slot H to the pin 12 to provide a stop against which the pin 12 may move and thus prevent the lever 35 from moving beyond the neutral position and into the running position. This stop which is actually the end of slot H in the link 58 is effective only during those portions of the use of the apparatus when the needle dipping function is about to be performed. The length of the slot H and its position along link 58 is such that when the solenoid 65 is energized the link 68 is moved upwardly to the position shown in Figure 4 and in this position the lower termination '10 of the slot H serves as an abutment against which the pin 12 can move, it being noted that when the link is up, the position of slot H is such that when the pin '12 is in the lower end of slot ll, viz. against end 70 the lever 35 is in the neutral position shown in full lines in Figure 4. Thus, by first energizing the solenoid 55 a stop is provided such that when the brake release solenoid 55 is subsequently energized, it will not pull the lever 35 downwardly beyond the neutral position. Yet the length of the slot II is such that when the solenoid 65 is de-energized and the link 55 is permitted to move downwardly to the position shown in Figure 2, enough length and position of slot is provided so that the pin 12 may move under control of the operator from the machine stop (brake on, clutch disengaged) position shown in full lines in Figure 2 all the way down through the neutral position (brake oif, clutch disengaged) and to the machine running position (brake oif, clutch engaged).

The energization of the solenoids 65 and 55 in the sequence just described is carried out by the mechanical action of the needle dipping mechanism now to be described.

Referring particularly to Figures 5 through 11, the mechanical needle dipping mechanism shown in Figures 5 and 6 includes a frame composed of side plates 15 and 15 which are fastened together by a plurality of cross frame members TI, 78, 19 and 85. Through the plates 15 and 16 there extends a pivot shaft 8| which is provided at its outer end with a firmly attached lever 82 to which a spring 83 is firmly attached at its outer end, the spring being anchored at its lower end on a pin 84 set into the side plate 15. The action of the spring 83 causes the outer end of the lever 82 to be pulled downwardly and this causes the shaft 8| to be rotated in the direction of arrow 58, as shown in Figure 5. Upon the shaft BI there is provided a segmental gear generally designated 85 which has a hub portion 85 pinned or otherwise firmly attached to the shaft 8| so as to be rotatable therewith. Into the hub 85 there is set a hand lever rod 89 which is bent at its upper end 99 so as to provide a hand grip portion by means of which the operator may grasp the lever and pull it towards her during the needle dipping function. The hub 86 has a segmental gear portion 9 l% extending through the angularity defined by the boundaries 92 and 93 of the gear. The gear has a segmental portion 94 provided with teeth which engage with a pinion gear 95 presently to be described. The action of spring 92 and lever 82 is to cause the segmental gear 85 to be moved in the direction 88 to a stop position which is provided by means of an adjustment screw 96 set in the cross frame member 19, the screw being positioned so that the edge 92 of 9 the segmental gear moves" against it when pulled inth'e direction of arrow '8 by the spring 83 and lever 8-2. The screw 96 can be adjusted and held in any adjusted position by means of the locking nut 91.

The gear 05, with which the teeth 04 on the segmental gear engage, is mounted upon a stationary pivot shaft I00, as shown in Figures 8-10. The stationary shaft I00has a flange at I and a reduced section I02 that fits neatly into a hole bored in the frame member I5. The reduced portion I02 is threaded at I03 to receive a cap screw I04 which passes'through washer I05. Thus, when the capscrew I04 is drawn up it pulls the reduced portion I02 firmly into the side plate I5 until the flange MI is tight against the inside of the side plate and this accordingly serves to position the pivot shaft I00 accurately onthe side plate. The opposite side plate '16 of the needle dipping mechanism 'is provided with a bearing hole at I06 whichis aligned coaxially with the stub-shaft I00. The bearinghole I06 serves to receive in journalingaction the shaft I08 which extends outwardly at I09 to receive the flexible coupling I I-0 terminating in the coupling block I II, by means of which the apparatus is attached to the shaft 100i the sewing machine. Upon the shaft I08 there is provided a heavy collar I I2 which is pinned'to the shaft. The collar II2 can be bored out so as to provide proper balance for the mechanism. Upon the inner end of the shaft I00 there is provided a cam generally designated 'II5 which is pinned to the shaft I08 so as to be rotatable therewith. The cam II5 has the shape shown best in Figure 11 and has a portion of maximum diameter 'I'IB extending from the radial line, II! to the radial line II8, and.a'portion of minimum diameter I I9 ,extending from the line IIB around to the line III. The portion of maximum diameter is generally of less than 180 degrees angularity, whereas the portion of minimum diameter 'I'I'0 is generally more than 180 degrees; The exact angularity between lines .I I! and Band hence of the cam portions H6 and H0 isvaried slightly for adjusting the device for different sewing machines, but it may be stated that the distance between the cam surfaces II 'I andIIfl is suchthat if the machine does not'stop at a point just short of where the stitch can be cast ofhthe sewing machine will be propelled in needle dipping'movement to that point and then on the reverse movement of the needle dipping mechanism to propel the machine in a direction opposite to stitch formation so as to bring the needle bar to the raised or fully retracted position so as to cast off the partially formed stitch. A slight allowance "in cam angle is usually required at each end of the cam to allow for coasting of the machine at the ends of each of these hand propelled directions of movement. I

The gear 95 is provided with a heavy boss por- 'tion I20 and is attached coaxially with the member I2 I. It may-be noted that the gear is drilled through at a plurality of places to receive at least two attaching screws l22-I22 which extend through the gear and into the member I2 I, which accordingly holds the gear and the member [2! firmly in coaxial relationship. It is to be understood, of course, that the entire gear 05 and member I2I could be made in one piece if so desired. v

The member I 2i is provided with a central land I23 which extends partly across the diameter'nf the member 121 ,frgm lines I24 to lines I25 of Figure 10. The land I23 has parallel sides at the lines I25- and I25 and a foreshortened top line at I25. At the sides and along the top of the member I2I there is provided a planar surface I2'I which is set at an angle to the axis of the member I2I, which is also coaxial with the shaft I00. The slanting portion I21 terminating at its lower end in the normal portion I28 which is at right angles to the axis of the member I2I. The land I23 serves as a place for mounting the movable cam engaging member I20 which is pivotally attached to the land by means of the pivot pin I20 set through the member I20 into the land I23, the member I20 being thus free to move pivotally in the direction of arrows I32 and I33 about the pivot pin I321. The member I20 is bifurcated at its lower portion having parts I34 and I35 which extend downwardly along the sides I24 and I25 of the land I23 and pin I30 extends all the way through. The member I29 has a generally circular periphery around a part of its periphery but is provided at its upper end with a protruding bosslike portion I36 which is nevertheless of the same thickness as the entire member I20.

The member I29 is provided with two inset pins I40 and MI, the pin I40 being set closer to the axis of shaft I06 than the pin IdI. The pin I40 has a smooth sharp edged planar end I42 which is parallel to the adjacent surface of the cam M5 when the'member I29 is in the position shown in Figures 8 and 9. The surface I42 is positioned so that it will fall into abutment with the portion I N5 of maximum diameter of the cam generally designated IIS when that portion of maximum diameter H6 is in angular position opposite the pin I40.

The pin II, which is mounted in the boss I36 of the member I29 is provided with a smoothly rounded outer end and engages upon the ar-cuate cam generally designated Hi6 attached to the wall "I6 of the needle dipping frame. The cam I45 is of partial segmental shape, as shown in Figure 11, and is provided with a slanted offend at It? and another slanted opposite end I48, as shown in Figure 10. As the member I2I is rotated about the axis of shaft I00 the pin slides up upon either the cam surface I01 or the cam surface Hi8 (depending upon directionof rotation)' until it reaches the point of maximum height of the cam at I49, at which point the member I20 is held in the position shown in Figures 8, 9 and 10.

Within the member I2I there is a recess I44 into which there is set a slug I50 which is pressed to the left, as shown in Figures 8-10, by means of the spring IEI. The slug I50 bears against the back surface of the member I29 and tends to move member I20 in the direction of the arrow I32 so as to move the pin I lI into engagement with the cam I46.

The entire needle dipping mechanical mechanism heretofore described is covered by a cover IE3 which extends downwardly along the, front of the mechanism and across the topof the mechanism where it is provided with a slot I54 aligned with the handle so as to permit movement of the handle from the full to the dottedline position shown in Figure 5 and is also provided with the outwardly extending contour at I52 which receives the upper portion of the segrmental gear 05 when in the dotted line position of Figure 5. The cover also extends downwardly across the back of the mechanism.

Within the needle dipping mechanism there are mounted two switches, as shown in Figure 7. One of these switches generally designated I55 is mounted upon the cross frame member 19 and is provided with an insulated actuating bar I55 set in alignment with the edge 92 of segmental gear generally designated 85. The gear is normally moved to the position shown in full lines in Figure '7 but is adapted to be moved in the direction of the solid arrow I45 when actuated by the operator, being returned in the direction of the dotted arrow I57 by the action of spring 83 and lever 82, as previously described. The insulated actuating bar I55 serves, when the gear 85 is in the released position shown in Figure '7, to hold open the pair of contacts I58 and I59, thus open circuiting the connecting wires I65 and I The other switch, which is mounted within the needle dipping mechanism, is shown generally at I52 and is provided with an insulated switch actuating member I63 positioned so as to be engaged by the protuberance I35 on the member I29. When the member I29 is in the position shown in Figure '7, which is also the position shown in Figures 8-11 in which the needle dipping mechanism reposes when not actuated by the operator, the insulating actuating member I53 serves to hold contacts I54 and I55 apart, thus open-circuiting the line I59 and line I 65. The line I 53 is one of the power supply lines of the apparatus, the other power supply line I58 being connected through lead I59 to the safety solenoid 65 and through the lead I19 to the brake release solenoid 55. From the safety solenoid 55 line ISI extends to the switch I55 previously described, and from the brake release solenoid line I65 extends to the switch I92. The switch I55 is adjusted so that it is moved to closed position by the slightest movement of the segmental gear 85 away from the released position shown in Figure '7, and switch I52 is adjusted and the cam surface on the lug I33 is shaped so that switch I92 closes after the switch, I55 has closed. Accordingly, when the operator operates the needle dipping mechanism by pulling forwardly on the lever 89 the switch I55 is the first one to be closed, and this accordingly immediately energizes the safety stop solenoid with the result that the link 68 is pulled to the position shown in Figure 4 and the lever 35 is thus prevented from being moved beyond the neutral position and into the running position. As the movement of the lever 89 of the needle dipping mechanism is continued, the switch I62 is closed and this energizes the brake release solenoid 55 with the result that it pulls down on the link 59 and causes the lever 35 to be drawn downwardly to the neutral position shown in Figure 4, but this quick downward movement due to the snap action of the solenoid 55 does not throw the lever beyond the neutral position because of the safety stop feature previously mentioned.

Referring now to Figures 12-29 which illustrate the action of the needle dipping mechanism, it may be stated before beginning the explanation that Figures 12-23 illustrate the sequence of the needle dipping operation when the machine has stopped with a stitch partially completed and beyond that point at which unlocking of the stitch can occur, whereas Figures 24-29 illustrate the first part of the action of the needle dipping mechanism under the condition where a stitch has just been started but has not reached the point just short of unlocking.

In explaining the sequence of Figures 24-29 these 7 figures run in sequence from Figure 24 through 29 and then the action continues exactly as in the sequence from Figures 14-23. In all of these figures the same nomenclature has been utilized.

The heavy arrow shown radially on cam II5 is intended to illustrate the position of the needle in the stitch forming operation, it being understood that the needle goes up and down in accordance with the vertical component of the heavy arrow shown in these figures. Thus, in Figure 13 the needle has proceeded beyond the fully down position shown at line I and is shown just as it has started its up run. Throughout all of these figures the arrow labeled For- Ward denotes the movement of the sewing machine in the stitch-forming direction, whereas the arrow labeled Reverse denotes the movement of the sewing machine in a direction opposite to stitch-formation. The arcuate dotted line dimensional arrows in all of these figures denote an idling operation, whereas the arcuate solid line dimensional arrows denote the condition where the needle dipping mechanism drives the sewing machine in either the forward or reverse direction, depending upon the point in the sequence of operation being depicted. The arcuate space labeled Coast denotes the amount of coasting of the sewing machine mechanism beyond the position to which it is driven by the needle dipping mechanism.

Referring now to Figures 12 and 13, the sewing machine has stopped with a stitch partially completed, but beyond the position at which unlocking (casting off) of the stitch will occur. The needle bar and needles of the sewing machine and cam II5, which rotates with the sewing machine, have passed the fully down position I80 for the needle and have come to rest at the position I8I in which the heavy arrow N is shown. The needle dipping mechanism herein illustrated always comes to rest with the lever 89 in the elevated position due to the action of spring 83 and lever 82 upon shaft 8|, Figure 6, and accordingly the segmental gear 85 and the gear is driven by handle 89 and the movable cam engaging member I'29 carried by gear 95, and which in turn carries pins I40 and MI, comes to rest and is held in the position shown in Figures 10 and 11, which are positions of reference for comparison with the positions shown in Figures 12 and 13. It will be remembered that the cam I I5, being attached to the sewing machine drive shaft, therefore always keeps a constant angular position with reference to the sewing machine and cam II5, therefore, is indicative of the position of the stitch-forming mechanism, including the needle bar and other devices for stitch-forming on the sewing machine. Arrow N is merely a reference arrow, the vertical component of which indicates the needle position. In Figure 13 the pin I40 which serves to propel the cam II5 has moved forwardly through an idle run, from the position shown in Figure 11 to the position shown in Figure 13, and during this movement the pin I4I has moved down the inclined cam surface I48 on the cam I45 and therefore permits the pin I40 to drop in behind the surface I I8 on the cam II5. Therefore, continued movement of the lever 89 by the operator causes the pin I40 to propel the cam H5 and hence to propel the sewing machine in the forward direction, from the Figure 13 to the Figure 15 position which is the next change in action position. From the position shown in Figure 13 the pin I40 accordingly drives the cam I I5 13 to the position shown in Figure 15, where the pin 'I4I begins to engage the surface I41 on the cam I46 and accordingly begins to move the pin I40 out from its condition of engagement with the surface H8 on the cam H5. However, complete disengagement of the pin I40 from surface H8 does not yet occur because the cam I4I must continue to ride up on the surface I41 for a slight distance, and therefore as the operator continues to pull the lever 89 in the forward direction (from Figure toward Figure 17), propulsion of the sewing machine (cam H5 via pin I) continues until the pin I4I rides to the top surface I49 of the cam I46 as shown in Figure 17, the pin I4Il being meanwhile completely released from behind the surface H8, and therefore it no longer tends to propel the cam H5. It will be remembered, however, that throughout the entire course of needle dipping operation, the brake of the drive motor, which normally holds the sewing machine shaft immovable, is released and hence the forward movement of the sewing machine, due to the operation of the needle dipper lever 89 continues (coasts) for a slight distance beyond the time of disengagement of the pin I40 from the surface H8 on cam H5. This coasting movement is indicated in Figure 1'7 as the distance between the lines I82 and I83 and is labeled coast. The amount of coasting for any individual needle dipping machine can be determined and the amount adjusted by changing the angular position between the surfaces H8 and I I1 upon the cam H5. In this way the needle dipping machine may be adjusted to suit any particular sewing machine and particular operator. Ordinarily, no considerable range of adjustment is needed after the needle dipper has once been adapted to a particular sewing machine.

When moving through the range of movements from the position of Figure 13 to the position of Figure 1'7, the needle has been propelled from its position where it is inserted into the cloth being sewn, as in Figure 13, thence forwardly to a fully retracted position designated by the dotted line I54 of Figure 15, at which time the original stitch. is completed. From this point on to the position shown by line I55, the further forward propulsion of the sewing machine starts a second stitch, which is,

however, not completed in Figure 15, nor is it completed as the propulsion of the machine in the forward direction comes to a halt, as shown in Figure 17. In this position the second stitch is carried forward but it is stopped short of the condition where the stitch may be unlocked by reverse movement of the sewing machine. This unlocking of the stitch is sometimes called casting off the stitch. In the position shown in Figure 1'7 the operator has pulled the handle 89 of the needle dipping mechanism to the fully forward position shown in dotted lines in Figure 5. In this position, lobe I35 on cam I29 again opens switch I52 (see Figure 7), and this action de-energizes brake solenoid .55 and accordingly permits spring .42 to lift arm 35 and set the brake. This prevents excessive coasting (over-travel) of the sewing machine due to the operators pull on the needle dipping mechanism handle 89. the handle or propels it backwardly toward the full line position. "By releasing the handle the spring 83 will propel the handle backwardly and will carry all of the mechanisms backwardly with the handle.

The operator then merely releases Hence, after the needle dipping mechanism has moved the apparatus to the position shown in Figure 17, it is assumed that the handle is released andbeginsto return in reverse direction to .its normal upright position shown in full' li-nes in Figure 5. From the position shown inFigure 17 the pins I40 and MI move through an idle run from the position of Figure 17, in which the pins I40 and MI are at line I55, around to the position shown in Figure 19, where they are atline I81. 'During the first part of this movement the pin I41 slides down the surface I41 of the cam I45 and permits the pin I40 to assume a position such that as the continued rotation of the pins by means of the needle dipping mechanism will later bring the pins into engagement with the surface II! on the cam H5, as shown in Figure 19. During this idle reverse run the cam H5 and the sewing machine which it propels remain stationary.

After the pin I46 engages the surface -I II, as shown in Figure 19, the cam H5 is propelled from the position shown in Figure 19 through the position shown in Figure 21 to the position shown in Figure 23. During that part of this propulsionbetween Figures 19 and 21, the pin I40 is fully in engagement with the surface II'I, but at the position shown in Figure 2-1, the pin I4I begins to slide up upon the surface I48 and after it has moved beyond the position shown in Figure 21, but before it reaches the position shown in Figure 23, this outward movement of the pin I4I on cam I48 causes the pin I40 to disengage from the surface II'I, after which the cam H5 and the sewing machine which it propels, coast to a stop through a distance shown by the dimension labeled Coast at I88 in Figure 23. In Figure 23 the machine has stopped with the needle in the fully retracted position, and as previously stated, in this position, the cloth and line of stitching which has been formed, can, when the presser foot is raised, be withdrawn from the machine and the needle thread or threads and the bobbin thread (or looper thread or threads), if used in the particular machine, can be pulled out smoothly any desired distance.

Referring now to Figures 24 through 29, there is in these figures illustrated the operation of the machine when the machine has come to rest with the stitch just barely started and where it has not reached" a point just short of looking. In this condition the needle N is shown at position I and the portion H5 or the cam is accordingly positioned so that it is in the way of the surface I42 on the pin I49. As the operator grasps the handle 89 of the needle dipping mechanism and propels it in the forward direction, the pins I4I ride off of the high spot I49 on the cam I46 and in sliding down the cam surface I48 permits the surface I42 of the pin I40 to come into engagement with the fiat surface -I9I of the cam I I5. In the continued movement from the position shown in Figure 25 through the position shown in Figure 27 and to the position shown in Figure 29 the pin I40 slides along the surface I9I of the cam H5, as shown in Figure 2-5. This is an idle run and. has no effect so far as turning the cam H5 and the sewing machine attached thereto. Finally, when the pin I40 reaches the position shown in Figure 29, it passes beyond the surface III of the cam H5 and accordingly permits the pin I40 to drop in behind that surface. However, the pins I40 and IM are being driven .in the forward direction by movement of handle 89 and, therefore, even though the pin I40 has dropped in behind surface II'I, it does not yet propel .the cam II but continues along a further idle run as denoted by the dotted arrow I92 until the pin I40 reaches the dotted line position shown in Figure 29 where it engages the surface IIS on the cam H5. By comparison it will be noted that in this latter position the pin I48 (dotted in Figure 29) is in the same position as shown for Figure and hence continued movement of the pin I40 in the forward and reverse direction, therefore, drives the cam H5 through the sequence of positions shown for Figures 1422'.

Accordingly, regardless of where the sewing machine happens to stop, it is only necessary that the operator grasp the handle 89 and pull it forwardly and then release the same, and the sewing machine stitch forming mechanisms will be carried forwardly and the stitching process of formation will be completed and another stitch partially formed or, if the stitch is already in the desired position, no action will be taken by the cam H5 and the machine will not be driven further in the forward direction. Then this other partially formed stitch is cast off by reverse action of the needle dipping mechanism on the sewing machine, thus completing the needle dipping function to permit withdrawal of the needle and bobbin (or looper) threads, Throughout this action the brake release and safety solenoids are applied, as previously described, so as to release the braking action of the drive mechanism and yet prevent the machine from being driven by the power source.

It will be understood that Figures 12 to 29 are merely illustrative of the action for specific initial stopping positions. However, the action above described will be carried out regardless of the position in the process of stitch formation at which the machine happens to stop.

Referring to Figures 30 and 31 there is illustrated a needle dipping mechanism which is precisely the same as that previously described, except that a gear has been inserted at 2&9. Accordingly, forward motion of the handle 89 in the direction of arrow QQI causes the gear 9:": to be propelled in a direction opposite to that previously described. The needle dipping mechanism shown in these figures is for a sewing ma chine in which stitch formation is accomplished when the power shaft of the sewing machine is driven oppositely to that shown for the device illustrated in Figures 1-29. Otherwise, the device is precisely the same.

Referring to Figures 32 and 33 there is illustrated a slightly modified form of cam I it which permits adjustment of the angular position between the lines II! and I I8 on the cam. In the cam structure shown in Figure 32, the cam generally designated 2H) is composed of three segments, viz. segments 2I I, 2I2 and 2I3. The segment 2I3 has a central boss portion 2M. and a cam surface portion 2I5. The segment ZIZ has a central boss portion 2I6 and a flanged segmental portion 2I2, which is positioned radially with respect to the shaft on which the cam parts are mounted so as to be in contact with the outer surface 2I8 of the cam part 2I5. The cam portion 2Il is a similar segmental part attached to a hub 2I9. It will be noted that the hubs 2 I4, 2I6 and 2I9 are in contact with each other and each is provided with a set screw, not illustrated, by which it is attached to the shaft I 8 of the sewing machine. The hub 2| 4 may, if desired, be

permanently attached to the shaft I 8 and set screws provided for only 2I6 and 2I9 to allow adjustment of these elements with reference to the member 2| 3. Thus, by loosening the set screws the hub 2I6 carrying the cam portion 212 may be adjusted from the full line position to the dotted line position of Figure 33 where it protrudes considerably beyond the ends of the cam portion 2I5 on hub 2M. Similarly, by loosening the set screw in the hub Elli the cam 2H may likewise be adjusted outwardly. The effective portion of the combined cam arrangement is the front surface along the lines 33-33 of Figure 32 and the terminal portions 229 and MI of the combined hub shown in Figure 33. Accordingly, by suitable adjustment the position of the terminal surface 229 can be changed to any position relative to the shaft I8 and likewise the terminal surface 22I may also be moved to any position relative to the shaft IS. The narrowest cam that can be produced is determined by the length 2| 5 of the cam portion, whereas the maximum is shown at the dotted line positions for Figure 33. A greater range of movement fron maximum to minimum for cam length can also be achieved by slightly different proportioning of the cam parts. This permits the adjustment of the cam to allow for different sewing machine inertia and also to allow for variation in the speed of actuation by the operator when this is desir able.

As many apparently Widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that we do not limit ourselves to the specific embodiments herein.

What we claim is:

1. A needle dipping mechanism for use in conjunction with sewing machines having a random needle stopping position at least one reciprocating thread carrying needle and mechanism cooperating therewith for forming stitches, and a rotary drive shaft for moving said needle and mechanism in said stitch forming relation, comprising a separate rotary drive member and means for limiting the rotation of said member to a predetermined distance first in a direction corresponding to the direction of rotation of said rotary drive shaft for stitch formation and then a predetermined distance in a reverse direction. clutch means for engaging said separate rotary drive member to said rotary drive shaft means cooperating with said clutch means to propel said rotary drive member and hence said rotary drive shaft in stitch forming direction from any place where it may have stopped in the process of stitch formation of the sewing machine through the completion of the stitch which was in the process of being formed when the machine stopped and into the formation of a succeeding stitch but short of the point in stitch formation where said stitch may be cast off and means then to propel said rotary drive member and said rotary drive shaft reversely until the needle of the sewing machine is substantially retracted.

2. The apparatus of claim 1 further characterized in that said rotary drive member includes a rotary shaft and operator controlled means for rotating the shaft forwardly and reversely.

3. The apparatus of claim 2 further characterized in that the operator propelled means includes a lever movable angularly through prescribed limits of travel and means connecting said lever and rotary drive member for rotating the same forwardly and reversely as said lever is manually moved angularlv.

4. The apparatus of claim 3 further characterized in that spring means is provided for normally rotating said rotary drive means in a direction opposite to the direction of stitch formation.

5. A needle dipping mechanism for use in conjunction with sewing machines having no predetermined needle stopping position and at least one reciprocating thread carrying needle and mechanism cooperating therewith for forming stitches, and a rotary drive shaft for moving said needle and mechanism in said stitch forming relation, comprising clutch having a rotary member connected to the rotary drive shaft of the sewing machine so as to rotate in constant synchronism therewith, said rotary member comprising one portion of the clutch, a second portion of the clutch separated from the rotary drive shaft engageable with the first portion so as to form a driving connection therewith, and movable means under the control of the operator and means limiting the movement thereof for rotating said second portion of the clutch a predetermined distance in a forward direction and means for automatically causing the engagement of the second portion of the clutch with the first portion to drive the rotary member and hence the sewing machine first in stitch forming direction from any position in the sequence of movements of stitch formation at which the machine may have stopped through the completion of the stitch in process of formation and thence into the formation of the next stitch, but short of the place in the stitch formation at which the stitch can be cast off, and then a predetermined distance in a direction opposite to the direction of stitch formation until the needle bar of the sewing machine is substantially elevated and means for then automatically disconnecting said clutch.

6. An apparatus of the type set forth in claim 5 further characterized in that said means under the control of the operator for rotating said second portion of the clutch includes a lever movable arcuately between predetermined limits and means connecting the lever and the second portion of the clutch for rotating the latter forwardly or reversely as said lever is moved forwardly or reversely.

7. An apparatus of the type set forth in claim 6 further characterized in that said lever is provided with biasing means for moving it to a datum position.

8. In a needle dipping mechanism for use in conjunction with sewing machines having at least one reciprocating thread-carrying needle and mechanism cooperating therewith for forming stitches, a rotary drive shaft for moving said needle and mechanism in said stitch forming direction, constantly rotating power means and cooperating clutch and brake means for connecting the power means to said rotary drive shaft for propelling the sewing machine in stitch forming direction and for disconnecting said rotary drive shaft from said power means, and for applying the brake for stopping the operation of the sewing machine, said clutch and brake means also including a neutral position where said clutch is disconnected and brake is not set, the improvement comprising a rotary member connected to the rotary drive shaft of the sewing machine so as to rotate in constant synchronism therewith, said rotary member including one part of a clutch, a second portion of the clutch engageable with the first portion so as to form a driving connection therewith, movable means under the control of the operator and means for limiting the movement thereof for rotating said second portion of the clutch and means for automatically causing the engagement of the first portion to drive the rotary members and hence the sewing machine, first in stitchforming direction from any position in the sequence of movements of stitch formation at which the machine may have stopped through the completion of the stitch in process of formation and thence into the formation of the next stitch, but short of the place in the stitch formation at which said next stitch can be cast off, and then in a direction opposite to the direction of stitch formation until the needle bar of the sewing machine is substantially elevated and means for then automatically disconnecting said clutch, said means under the control of the operator including also means for automatically disconnecting the brake of said drive mechanism and means to prevent engaging the clutch thereof prior to movement of the sewing machine by said means under the control of the operator.

9. An apparatus of the type set forth in claim 8 further characterized in that said means under the control of the operator comprises a lever movable arcuately between predetermined conditions and includes means connecting said lever to said second portion of the clutch for moving the latter forwardly as the lever is moved in one direction and reversely as said lever is moved in the opposite direction.

10. The apparatus of claim 8 further characterized in that said means under the control of the operator includes a first electrical switch and a solenoid energized through said first electrical switch, said first electrical switch being actuated and said solenoid energized when said means under the control of the operator is moved from a normal position so as to actuate said solenoid, and first solenoid operated means operable to disconnect the brake of said power means, Without, however, engaging the clutch.

11. The apparatus of claim 1-0 further characterized in that said means under the control of the operator includes a second electrical switch and a second solenoid energized through said second electrical switch, means to actuate said second electrical switch before the first electrical switch so as to actuate the second solenoid controlled thereby, and second solenoid actuated means operable to prevent movement of said clutch-brake mechanism to a position where the clutch is engaged.

FRANKLIN CHATFIELD. STANLEY ROBERTS FOLSOM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 192,886 Warner July 10, 1877 1,352,226 Schoenky Sept. 7, 1920 1,850,708 Davis Mar. 22, 1932 2,158,484 Poole et a1 May 16, 1939 2,277,475 Bilger Mar. 24, 1942 FOREIGN PATENTS Number Country Date 576,765 Great Britain Apr. 17, 1946

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