US1549081A - Rotary take-up for sewing machines - Google Patents

Description

Aug. 11; 1925. 1,549,081

. R. K. HOHMANN ROTARY TAKE-UP FOR SEWING MACHINES Filed Oct. 29, 1921 3 Sheets-Sheet 1 Au 11, 1925. I

1,549,081 R. K. HOHMANN 1 v ROTARY TAKE-UP FOR SEWING MACHINES I Fiied Oct. 29, 1921 ssneets-snet 2 I 8 VENTOI? 1% M [MM Patented Aug. 11,1925.

omrsn STATES PATENTOFFHIC'E.

RICHARD K. HQHMANN, OF PERU, INDIANA, ASSIGNOR TO .HOHMANN SEWING MA- CHINE COMPANY, OF PERU, INDIANA, A CORPORATION OF INDIANA.

ROTARY TAKE-UP roa SEWING macnmns.

Application filed October 29, 1921. Serial No. 511,407.

o all whom it may concern.

Be it known that I, RICHARD K. Hon- MANN, a citizen of the United States,'and resident of Peru. in the county of Miami and State of Indiana, have invented certain new and useful Improvements in Rotary Take-' Ups for Sewing Machines, of which the following is a specification.

The general object of my present invention is to provide improved means for feeding and drawingthe thread back and forth through the eye of the needle of a sewing machine as required to provide the needle thread used in the needle thread stitches,

T and to form and draw up the thread loops made in the stitch forming operation.

My invention comprises 'a-novel rotary take-up mechanism proper, which preterablv is associated with provisions for automatically adjusting the thread take-up movement to compensate for variations in the thickness of the material sewed, and preferably also, is associated with means for drawing the thread from the supply spool as required without subjecting the take-up mechanism to the variable pull of the needle thread required to draw the thread ofi' the supply spool, and with means-for prevent ing the thread from collecting in the takeup mechanism in case the thread breaks at the work. My novel take-up mechanism is distinguished from other rotary take-up mechanisms heretofore devised by a special arangement of thread guides and rotatable thread deflecting studs whereby a relatively large take-up effect is obtained with a relatively short amount of thread in the takeup mechanism, 'and whereby the thread loops formed may readily lee-expanded and con-- tracted at the proper stages of the stitching operation. The comparative shortness of the portion of the thread in the take-us mechanism at any one time makes the threa relatively easy to control in the different stages of the stitch-forming operation, and minimizes the liability to thread breakage and reduces thetrouble resulting from such breakage.

My invention was primarily devised for use inhigh speed rotary hook sewing machines in which the thread bobbin is several times larger than those now in use, and the size of the thread loops passed around the bobbin and it'sjcarrier are correspondingly increased.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification.

' For a better understanding of the invention,

however.

, .and its advantages, reference should be had to the accompanying d'raw- A ings in which I have illustrated a preferred form of embodiment of my invention.

Of the drawings:

Fig. 1 is a. side elevation, with parts broken away and in section of a. sewing machine head; I

shown in Fig. '1;

Fig. 3 is a view taken similarly to Fig. 2

Fig. 2 is an end elevation of the apparatus but showingtheparts in different relative positions Fig. 4 is anend elevation of a portionof the machine with some parts removed;

Fig. 5 is a section on the Fig. 2;

Fig. 6,is a side elevation of'the take-up mechanism proper;

Fig. is an end elevation ofa portion of the thread -take-up guide; and

is a section on the linev 8-8 of In the drawings I have shown my invention embodied in a'sewing machine comprising a table or base A and an arm A of the u'sualiform. J ournalled in the arm A is a main shaft B which comprises a crank portion B through which the usual needle bar A .C is reciprocated by the connecting rod 0'.

Mounted in the sewingmachine head is the usual presser ba-r D which carries the presser foot D and is normally depressed by a. spring in the adjustable housing D Beneaththe table- A-is the looper shaft E driven in timed relation withthe main shaft B, as by belt 1B which runs over'pulleys which are carried by the two shatts and are ordinarily so" relatively proportioned that the looper shaftE will make two revolutions for each revolution of. the shaft B. At its' I front end the shaft E carries a looptaker F provided'with a beak or hook F for drawingaloop'inthe needle thread and carrying v the loop about the non-rotatable. bobbin housing or carier G. I represents the. usual tension device through which the. needle thread passes from the supply spool to "the take-up mechanism'and needle, and D represents a lever connected to the presser bar D. for actuating the tension device I to release the thread when the presser bar is raised to permit the insertion and removal of the work. In so 'far'as above described the sewing machinemechanism may be, and

' isshown asbeing, like those now known and members and rotate'withthe shaft B. As shown the engaging t e rear in general use except that thethread carrier and looptaker are shown as larger in diameter than in sewing machines in common use.

My improved take-up mechanism, in the form shown, comprises two coaxial disc like 'and: K which are secured to,

disc K is secured to the end of the shaftB by screws K, and theidisc K is spaced away from and is connected to the disc K by thread-engaging studsK and K. The stud K is located adjacentthe periphery of the discs while "the stud K, which, having reference to the direction of rotation of the discs, is angularly back from the stud K, and is intermediate the axis of the shaft.

I stationary thread guide back of the discs K and .K which, as shown, comprises'a dish sha ed memberL mounted int-he arm A,

-an a disc-L, secured to the member L but spaced away from thelatter at their under 5 sides to provide a thread channel L 'open at.

its lower edge and the upperedge ofwhich is represented in Fig; '2 by the dottedline L. The front face of the disc Lis spaced away from the discK sufliciently to avoid fri'cthe portion of the-needle thread running tional contact with the latter', ="and the disc 7 K is preferably provided witha flange or V rib K at its rear side to prevent the portion of the thread which should'pass'through the channel L from entering the space between the discs L and 'K fl' The disc L has 'its edgebevelled, as indicated at L, andthe b0 y portion L, of the member L is tapered t guide the thread into theehannel L54, a

. The means shown foricompensating';for.

the thickness of the goods sewedcomprises a 4 lever M provided with an eye M nigh-1116 needle thread at one. end, and. ivotally ;con'-" nected-at its op osite end to t e'sewingfmachine head as y means of the-screw M Intermediate its ends the lever rM. is "pivotally connected to the presse e) I) the connection being formed, as shown, by stud DM carried by a bracket D which is adjustably secured to the presser bar D as by the clamping screw D*. The stud DM passes through a slot formed in the lever M. With this arrangement, as the presser bar D is raised or lowered by the engagement of the presser foot D with the top of Work of greater or less thickness, the thread eye M of the lever M is correspondingly raised and lowered through distances several times those through which the presser bar itself is moved. v

; To pull the thread off the needle thread supply spool- (not-shown) as required, and thereby prevent the. operation of the takeup mechanism from being affected by .the

variable resistance of the thread as it is pulled off the'spool, I rovidea thread pul-- ler to act on the threa between the supply spool andtension. The thread puller is in the form of a bent arm N carried by the needle bar C and projecting through the slot A in the frame arm A. The arm N is formed with a fork N" at its outer and upper end which, at the end of each upstroke of the needle bar, engages and formsa bight in the portion of the needle thre'ad T running between a pairof thread guide eyes 0 "and O secured to the arm A'.-

The needle thread T, in the construction illustrated, runs from the supply spool (not shown) through a'thread guide. 0 to the thread guides O and O and thence to the tension device I from which it passes into the. eye M of the lever M. From the eye M the thread passes backof the finger H at from the eye M to the guide .0 is engaged on its-upper side by the take-up stud K and deflected away from the straight line between theey'e M and the guide 0 during a portion of each rotation of the driving shaft, and the portion of'the thread runnin from the guide 0? to the guide 0 is en age at its under side by the studs K" and 5 in {varying degrees aslthe studs .travel around their orbit and thereby deflected away from the straight line betweengthe guides '0 and 0 The maximum'aggre'gate deflection of the thread extending from the lever e e M to the guide 0' is reached at the comp etion of each stitch when ;.the;a pparatus is in the position shown in Fig. 2. As'the parts move from the position shown inlii'g. 2 in the succeeding stitch forming operation, the thread blght engaged by the stud K and that'e'ngaged by the stud K": are each permitted to shorten as the needle descends through the workand the needle thread is engaged below the work by the hook F and drawn into a loop which is-carried about the bobbin car-.

rier. Fig. '3 represents the condition of the apparatus when the loop passed about the.

bobbin carrier is fully distended. In'Fig. 3 the needle bar is a little below the top of its stroke as is the case also with the apparatus in the position shown in Fig. 2. In moving 7 from'the position shown in Fig. 2 into that shown in Fig. 3, thestnd K quickly passes out of engagement with the needle thread and does not engage the latter until after the apparatus has movedfrom the ---position shown in Fig. 3 toward that'shown in Fig. 2. As shown, however, the portion of the thread extending between the guide and the guide 0 is constantly engaged by one or other or both of the studs K and K, which thus exert a controlling influence 'on' the thread, while the bobbin encircling 100%; are being formed as well-as when they are ing.

, drawn up. 1 w

Distinguishing characteristics of my takeup' mechanism are the relatively large amount of thread take-up movement obtain a'ble with a. rotary take-up mechanism trgiven diameter, and the small length or thread in the take-up .me'chanism between the eye M and guide 0. at any time in comparisionwith the amount of thread take-u movement obtained. YA reduction in di amet'er of the takeup mechanism is of great importance in a high speed sewing machine not only because it'reduces the bulk of the take-up" mechanism and the. centrifugal stresses acting .ongthettakeeu-p mechanism -proper, bu't alsobecause. it' facilitates the manipulation of thethread, reduces the ten- 'dency thread breakage and minimizes the annoyance and trouble produced incase .of thread breakage which inevitably occurs pf lrofn time to time in the operation of the 1 sewing machine. The" location of the guides 50 M, 0' and 0 relative to one another and to the y of movement of the deflecting studs K the latter, all contribute to thef relatively great take-up movement obtainable with a take-up of givengdiam'eter, and to make the amount of thread in the take-up mechanismat one time relatively small. T 9 When the needle thread; breaks -in sewing -it ordinarily breaksjat thei-j work," andwith ordinary,rotaryv take-up mechanisms sueh breakage is 'apt1 ',;tol -;result in annoyaiieeanddelay as .well as thread waster-be cause/"0f of r esus thread.

aboutthe thread'deflecti-ng studs or other rotating portions of the take up mechanism.

- presser foot pr "amount of thread. take"? thick goodsgrthangj ivith' t 1n amount of makeu 'producedbythe take-up and K, and the relative location or Toavoid this trouble with the mechanism. :shown Ihave provided a thread catcher which will engage thepo'rtion of the thread in the take-upiriechahmm adjacent the eye BIC- 111d hold it so that the stud K will break thethread at this int whenever the portionof thethread 1n the channel L is allowed, to slacken-as it does when the thread breaks at the work. In the construction illustrated I form .this thread catcher by cutp'ing groove between the projection L anl the .under edge of the hook L". -Wi th this arrangement' when the thread passing through the channel L? is permitted to slacken as it does when the needle thread'breaks at the 5 ting a notchLEjn the disc L? .to provide a r hook ,Lt-atj theperiphery of the disc L adjacenttheey'e M",;a'nd by extending a rojeo' 'tion. L from' the plate Linto the note L so flaisfto forma crotch or V-shaped thread grip-' so l work, the take-up, stud K almost instantly,

that is, within: a few turns of the takeup mechanism, works the slack thread into a position-in which the thread is caught in the any threadat all is drawn into theltak'e-u When working witl i relatively thick work i the presser foot D is "maintained higher above the table Athan when working on thin work. The chalages in elevation of the magnified .changesin elevation of the eye guide M of the lever M. -With: the arrangement shown, any; upward mo v efme'ntof the eye guide M'. increases and. any downward movement oi thefeye "decreases the extent of deflection and consequentlyetheamountof thread take up stud K thus automatically provid ng emissary-with good'l, Th

theg greater uces corresponding but mechanism disclosed can be adjusted by rais- I ing and lowering the 'Tbracket which is adjustably clampedte the presseribar Dxand is y pivotally eonnected to'the lever M.

While-in accordance with the provisions of the statutes Iy-haveillustrated anddescribed the besfig'iormlof my invention now known to.

me, it will apparent'to those skilled'in the artfthatchaiiges'ma 'be made in the form of {the :aapparatua. disc sed flwith'outldeparting' -lfrom thev spirit of my inventlonT asset forth in the appended claims, and that certain fea- --tures ofm.y invention may-sometimes be used .Qeadvantagewithout a corresponding use of other features.

Having now de'scribed my invention,what

; I{ ,claim as newand desire to secure byImters Patent, is

1. In a rotary take-up mechanism the combination with a rotating member of a thread deflector carried thereby, a second thread deflector carried by said member and displaced relatively to the first deflector axially and backward having reference to the'rotative movement of said member and three nonrotating thread guides outside of the orbital paths of said deflectors and located one about 1 90 in advance of the second and the third in advanceof said one deflector and less than 180 in advance of said second deflector having reference to the rotative movement of said member,said guides and deflectors being relatively disposed and adapted for the passage of the thread toward the needle from said third thread guide to said second guide beneath and in the path of said second deflector and from said second guide to said first guide over and in engagement with the first mentioned thread deflector.

2. In a rotary take-up mechanism the combination with a pair of angularly and axially displaced rotating thread deflecting studs, of a thread guide at one side of the take-up mechanism, a second guide at the opposite side of the take-up mechanism and a third guide below the take-up mechanism with the needle thread passing between saidfirst and second guides in position to be enaged by one of said studs and passing from t e second guide tothe third guide in position to be engaged by the other of said studs, and means for adjusting the relative angular positions of said guides to vary the extent of the take-up.

3.- In a rotary take-up mechanism, the combination with a thread deflecting stud moving in an orbital path, of a stationary thread guide formed with a kerf-like thread channel located within said path, and means for holding the thread insaid channel with its projecting portions projectin therefrom across the path of movement of the stud.

4. In a rotary take-up mechahism the combination with a rotating disk and athread deflecting studcarried thereby of a stationary thread guide formed with a kerflike thread channel within the path of 'rotation oftsaid stud, means for holding the thread in said'channel with its ends projecting across the path of movement of said stud, said disc being, provided with; a peripheral rib on its face adjacent said guide to prevent the thread from working into the space between the guide and disc.

5. In a sewing machine, the combination with ,a presser bar and a rotary take-up. mechanism comprising a thread deflecting stud travellin in an orbital path of means actuated by t e adjustmentof the presser barresultin from difli'erences in work thickness for a justing. the amount of thread take-up, said means comprising a lever piv--.

oted to a stationary support and connected engaged by said stud, one of'said to said presser bar to be oscillated relative to said support when the presser bar is adjusted, and provided with a guide eye for the thread, and a second thread guide to which the needle thread portion engaged by said deflecting stud passes from said guide eye, said guide eye and second thread eye being horizontally displaced in opposite to accommodate differences in work thickness' will move the line connectin said thread guides toward or away from t e axis of rotation of said stud and thereby eifect a compensating adjustment in the amount of thread take-up.

7. In a sewing machine having a rotat ng take-up, the combination with a rotating thread deflecting stud, of guides between which the thread passes in position to be being adjustable to move the threa running between the guides toward and away from the axis of rotation of said stud and thereby vary the amount of thread deflection produced by said'stud. b

8. "n a sewing machine, comprlsing a 7 thread tension device, a needle bar and needle, and a take-up mechanism interposed between the tension device and needle, of a thread puller, connected to theneedle bar and engaging the thread at the opposlte side ides of the tension from the take-up mechanism and pulling the'thread'on the rising movement of the needle bar.

9. In a rotary hook mechamsm for sewing machines, having a. thread tension, the

combimation with a rotary take up mechanism comprising a stud travelling in an orbital path, a thread guide to w 1ch the needle t read .passes. from said tension dej vice, a second thread guide to which the needle thread passes from the first mentioned guide, both of said guides lying without sa1d path but so located relatively thereto. that. the thread portion running between said guides when under tension assumes a 'POSItlOH intersecting the movement of said stud except w gaged by said stud, "and thereby deflected path of en enfrom sa1d position, and a thread catcher which is located within said path at the oppo'site side of said position from that to-v ward which the stud deflects the thread, and

by which the thread portion running between 'said guides is caught when the normal thread tension is released by the breaking of the thread between the take up and the work, whereby when the thread is caught by said thread catcher it is engaged by said stud between the thread catcher RICHARD K. HOHMANN

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