US1338348A - Sewing-machine - Google Patents

Description

F. ZALESKI.

SEWING MACHINE.

APPLlcAHoN FILED MAY1s,191a.

1,838,848. Patented'Apr. 27, 1920.

4 SHEETS-SHEET I.

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` Frank ZuleSKi WMMQMJ ff Atys.

F. ZALESKI.

SEWING MACHINE.

APPucATloN FILED MAY13, |918.

Patented Apr. 27, 1920.

4 SHEETS-SHEET 2.

FfunK Zc1\eSK 67 68 Anys.

F. ZALESKI.

SEWING MACHINE.

APPLICATlON FILED MAY I3, I9I8.

Patented Apr. 27, 1920.

4 SHEETS-SHEET s.

M' A'rfys.

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SEWING MACHINE.

APPLxcATloN mio MAYIB. 19m.

Patented Apr. 27,1920.

4 SHEETS-SHEET 4.

FTcmK ZulesKi by @am Mal/W Anya eration and t en to FRANK ZALESKI, 0F BOSTON, MASSACHUSETTS, ASSIGNOR TO THE REECE BUTTON HOLE MACHINE` COMPANY, OF BOSTON, MASSACHUSETTS, A 'CORPORATION OF MAINE.

SEWING-MACHINE.

Specification of Letters Patent.

i Patented Apr. 27, 1920.

Original application filed DecemberS, 1917, Serial No. 206,215. 4Divided and this application led May 13,

- 1918. Serial No. 234,047.

To all whom t mag/concern:

Be' it known that I, FRANK ZAL'ESKI, a

subject of the Emperor of Germany, residing accompanying drawing, is a specification,

like characters on the drawing representing'l like parts. v

This invention relates to sewing machines of that type which are` provided with upper-thread-handling mechanism and under thread-handling mechanism and are adapted tol perform a predetermined stitching opbe automatically brought to rest. As an example of sewing machines would refer to buttonhole sewthat are adapted when set inI form the overseam stitches on operation to to be brought-torest a buttonhole and then automatically at the completion of the but-v tonhole. Some sewing machines, of this type are provided with means end of the-stitching operation; and the present invention relates particularly to a sewing machine of thistype.

The upper-thread-handlingmechanism usually comprises an eye-pointed needle by which the upper thread is manipulated, and the under-thread-handling mechanism includes alooper arranged to take the loops of upper thread as they are inserted through the work by theupper needle and an under needle for inserting through the loops of upper thread.

Sewing machines of this type are usually constructed and arrangediso' that when they are brought to rest at the end of each seam or stitching operation, the upper needle is in raised position and the upper thread from .the upper needle extends through the work and around the looper of the under-thread-y handling mechanism. Hence' on the under side of the work there will be found not only the under thread leading from the work to ltion of the looper during the last stitchbut also the loop of the source of supply,

work

upper thread which extends from the under the looper and back through the workagain to the upper needle.

If a sewing machine of this type 'is provided with threadtrimming mechanism for trimmingthe under thread close to the work of which the folwhich is apt yhandling mechanism, and

for. cutting the under thread beneath the work at1 the 'operate loops of under thread at theend of 'the stitching operation, such thread-trimming mechanism will operate to cut not only the under thread, but also the loop of upper thread which is held by the looper. This cutting of the loop of upper thread to drop intd the under-threadafter the machine has been in operation for a considerable time there will be quitean accumulation of such thread ends which are apt to clog up or in-4 terfere .with the operations o'f the underthread-handling mechanism.

The object ofthe present provide a construction by which the product ionof these thread ends will be prevented and I accomplish thisv herein by means which becomes operative during the forming of the last stitch to prevent the looper from will produce a. short length of thread invention is to engaging the loopof upperA thread so that when. the sewing machine is brou ht to rest with the needle raised there will Fe no loop of upper thread held by the looper and the thread-trimming mechanism, therefore, will only on the under thread.

In order to give an understanding of my 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.

In the drawings, `Figure 1 isa side'view of a sewing machine embodying my invention;

Fig. 2 is a plan view of the driving and stopping mechanism therefor;

Fig. 3 is a plan view ofthe work-holding means;

Fig. 4 is a fragmentaryl View showing the thread-trimming device;

Fig. 5 is a view of theunder-threadhandling mechanism;

Fig. 6 is a' top plan view of the underthread-handling mechanism; V

Fig. 7 is a fragmentary view showing the normal operation of the looper;

'Figs 8 and 9 are views showing the operaforming' movement;

Fig. 10 is a section on holel sewing vmachine of the well-known Reece type, an example of which may be found in United States Letters Patent No. 1,188,942, dated June 27, 1916. This sewing machine comprises work-holding means by which the Work is held and stitch-forming mechanism for producing the buttonhole stitches. The Work-holding means is in the form of a clamp plate l which is slidably mounted upon the bed plate 2 of the sewing machine frame and Work clamps 3 carried by arms 4 pivoted to the clamp plate and which are movable toward and from the clamp plate for clamping theV Work w 'and releasing it.

The stitch-formin mechanism comprises upper thread-handling mechanism in the form of an eye-pointed needle 5 carried by the needle bar 6 which is mounted for vertical reciprocation in the head or overhanging arm 7 of the frame, and an under-threadhandling mechanism which is mounted/on a rotary turret 8 and which comprises an under or lower oscillating needle 9 and aI looper 1,0. The turret 8 is mounted for rotation in suitable bearings 11 carried by the depending portion 12 of the frame, and it i is provided at its upper end with a throatplate 13 having an opening 99 through which the upper and under needles operate. The required movements of the under needle 9 and looper 10 are secured from a'spindle 20 which is mounted in the turret for vertical reciprocation. i f

The looper 10 is secured'toy a block 79 pivoted at 91 to the turret 8, said block having a cam slot 78 therein in which cperatesa roll 77 carried by the spindle 20. Ther vertical movements of the spindle thus operate through the cam slot to oscillate the block 79 and the looper 10. -The spindle is connected at its lower end to a'rocking lever 21 pivotally mounted at 2,2, therear end of said lever having a link 23 connected thereto which is actuated from an eccentric on the driving shaft 24 of the stitch-forming mechanism..

The turret has a pinion 14 rigid thereWit which meshes With a segmental gear 15 carried by a rockshaft 16, and the needle bar 6 also has a pinion 17 thereon which meshes with a segmental gear 18 carried by vthe rock-shaft 16. The rock-shaft 16 is oper- :ated at the proper time from a main cam 19 so as to turn the turret and upper needle during the stitching around the ends of the buttonhole. The work-holding means and the stitch-forming mechanism are ar ranged to have a movement relative to each other, and in the machine herein shown, this movement is provided for by making the Work-holding means capable of reciprocat-A ing movement on the bed plate, such reciprocating movement being derived from the feed cam 19 by any suitable means usually7 employed in buttonhole machines of' this type.

25 indicates a buttonhole cutter pivotally mounted to the frame at 26 and which is actuated from the cani 19 at the proper vtime to cut the buttonhole.

I have above referred briefly to some of vthe essential parts of a buttonhole sewing machine of the type above mentioned, and before entering into a description of my im-` provements, I will recite briefly the sequence of operationsperformed in stitching a buttonliole.

Then the machine is at rest, the needle 5 and work clamp 3 are both raised and the Work-holding means is so positioned that the Work w supported thereby will be Vplaced properly to have the buttonhole cut therein Aby the cutter 25, this being referred to as vshaft 24 is set in operation to actuate the stitch-forming mechanism to cause it toy produce a series of stitch-forming movements which form the edge stitches on 'the cut buttonhole. During the stitching operation the work-holding means is given a slow feeding movement first in one direction and then in the other to cause the stitches to 'be formed down one side of the buttonhole -and lthen bacli along the other side, the

stitch-forming mechanism being rotated at the ends of the buttonhole so 'that the stitches Will'be properly formed around the buttonhole end. When the stitchingfon theV buttonhole is completed, the shaft p24 is brought to rest automatically by a suitable stop motion, the work clamps 3 are raised, l

and the Work-holding means is given a'quick movement to the right, Fig. 1, to bring it from stitching to buttonhole-cutting position again, at which time the machine comes4 to rest.

The shaft 24 is driven from a driving belt,

and said shaft is started in operation or,

brought to lrest by shifting the belt either onto the pulley 39 which is fast on the shaft, or onto the pulley 40 Which is loose on the shaft. The shifting of the belt is accomplished by a belt shifter 41 carried by a belt-shifting rod 42. When the belt is shifted onto the loose pulley 40, 'the machine is brought to rest with the needle raised by means of a stop motion which is herein shown as comprising a stop cam 43 fast on the shaft 24, and a stop member44 which is yieldingly carried by an arm -45 fast on the application, Se.

is va division,

cani with the stop member 44 will produce,

a braking effect, and when the stop cam has been turned into the position shown `in Fig. 1 so that the notch 47 therein comes in line with the end 48 of the member 44, said end will drop into the .notchtherebypositively stopping the shaft 24.

The machine herein shown is provided with means for seizing and gripping the under thread at the end fof the stitching operation and also means for severing lthe under thread betweenthe holding means and the work. The means for seizing and holding theunder thread is similar to that illustrated and described in my co-pending No. 206,215 filed December of which and is in the form of acurved arm 27 fast on a rock-shaft 29 mounted in bearings in a bracket 30 carried by the turret, said arm having a hook 2R at the end thereof. The arm 27 is normally held .in the `position shown in Fig. 6 and the rock-shaft 29 has an arm 82 thereon-.situated to be engaged by a lever or arm 33 pivoted at 34 to the frame and actedl upon by a spring 35 which norniallyliolds -it against the stop 37.

In the operationy of the machine after the i stitch-forming mechanism has been brought to rest yand while the work is being carried from stitching to buttonhole-cut'ting -position the turret is turning clockwise, Fig. 6, during which movement the arm 32 will engage the armor lever 33, and as the arm 32 is wiping past the arml, the hook 27 will be swung to the left'Fig. G. lVhen*v the arm 32 passes oiffrom the arm 33, the hook will be returned to the position shown in Fig. G. i During this swinging movement of the hook 28 it-engages the under thread and draws the latter to one side against the y,

under face of the throat -platejl'i l.The machine herein shown is also pro'i-'ided with means for cutting the under thread close to the Work after it has been clamped to the throat-plate 13. Such thread-cutting mechanism is similar to that illustrated and described in my above-mentioned co-pending application Se. No. 206,215.l filed December 8, 1917, .and comprises two levers 51, pivotally mounted on two studs 53` to shift the belt onto the loose' the present applicationl held by the looper 1() and 540, respectively, that are carried by.a plate 55 whichy is removably secured. to the clamp plate 1 by means of screws 56. The lever 51 carriesy at lits end .a cutting block 57 and the lever 52 carries at its 'end a knife 530, said knife and cuttngblock op-v erating in' close proximity to the upper face of the clamp plate` 1. The opposite ends of the levers are connected by a fspring 54 which tends vto separate the operative ends from each-other. levers is a toggle device comprising two toggle members 58, 59 pivotally connected block. Means are provided for thus straightening the toggle levenafter the.

stitching operation is completed and while Situated between ythe i the work is being carried from stitching to Abuttonhole-cutting position. Such means comprises a lever 63 pivoted at 64 to the plate 55 and connected atone end to the stud 6() of the toggle device, the other end 66 of the lever projecting beyond the clamp plate and operating in a recess 67 formed in the controlling' member 68"that is car-y ried by the' bed-plate2 of the machine. AThe recess 67 lis so positioned and of such dimensions that during the movement of the clamp plate rl from stitching to buttonholecutting position, theend be brought` against the .shoulder G9 ofy the recess thereby turning `the lever and straightening the toggle device. l1`he under thread will thus be cut close to the work during the -movement ofthe clamp plate fromv stitching to buttonhole-cutting position.

` In the ordinary operation of a sewing machine of this type the upper 'needle carries a'loop of upper thread t through the work andthrough a loop of under thread at each penetrating thrust and. the looper 10 is actuatedv to engage each loop 'of 'upper threadvafter it 'has' been carried through the work. and through the loop of under raised..` Hence when a sewing machine of this type: is brought to rest with the needle 5, raised, a loop of under tliread will be cut beneath the work by threatwutting mechanism. such as above 'described` a short length` of thread will be produced which 6G ofthe lever will and if the thread is constitutes the loop of upper thread. One Such short length will result from each buttonhole and after the machine has been in operation for sometime the accumulation of these short lengths is apt tol clog up and n interferev with `the operation of the lunder thread mechanism.

It is the object of my present invention to provide means for preventing the looper from engaging the'loop of upper thread during the last stitch-forming movement, so that when the machine is brought to rest there will be no loop of upper thread held v by the looper. Y Conse uently, the operation ing a roll 77 which operates'in a cam slot 78 formed in a member 79 that 4is connected to the looper, and that during the stitching operation the vertical reciprocations of-'thel spindle 20 occur at such intervals as to cause the looper to properly entereach' loop ofupper thread. This operation i's illustrated diagrammatically in' Fig. 7l -wherein the needle 5 is illustrated as being withdrawn from the work, thus to throw out thel loop t of upper thread and lthe point of the looper 10 is illustrated as just enteringthe loop t.

t of upper thread.l I propose to secure this To cause kthe looper tomiss the loop during the last stitch-forming movement, the

movement of the spindle 20 is retarded so that the forward movement of the looper will not occur until after the needle l5. has been raised to such a point as to'lift theloop t of upper thread above the looper. If, for instance, when the needle is in the position shown in Fig. 7, the looper 10 is retracted to occupy the position shown in Fig. 8, then bythe time the looperreaches the point of the needle, the latter will be elevated into the position shown in Fig. 9, in which position the'eye of the needle is above the looper and the looper will, therefore, miss the loop retardi'ng or`retracting Imovement of the looper by means controlledlb'y the stop'motion lso that just when the machine is coming to rest and the needle 5 is being raised during the last stitch-forming movement,

.- l the looper will receive its retarding or retracting movement and will thus skip lthe last stitch. The lever 21 by which the spindle 20 is, given its vertical reciprocation is pivotally mounted on a pivotal pin 22 carried by the frame 12. The ends 8() of this pivotal pin which is journaled in the plate.

retarding A' frame 12 are eccentrically situated, and as a result, if the pivotall pin 22 is turned about its ends 80 asA an axis, the lever 21 will be raised or lowered, and since the rear 'end of the lever is connected tov the rod 23', such raising or lowering will be effective at the front end where it is connected to the spin dle 20. One of the ends 80 has an arm 8l fast thereon which is connected to the lower end of a rod 82 that extends up through the bed plate and is connected at its upperl end toa lever 83 fast on a rock-shaft 84 that is journaled in a bracket 85 carried by the bed Said rock-shaft has an arm 86 fast thereon which is situated in position to be engaged by a finger 87 extending from the stop member 44 when said stop memberis being depressed b the stop cam. Hence, when the stop motion is set in operation to bring the machine to rest and the'stop cam is acting on the stop member 44, the downward swinging movement of the latter will rock the lever 83 thereby raising the .rod 82 and turning the pin 22. Thiswill raise .the lever 21 and consequently raise the spindle 20 slightly, such movementv operating to retract or rethe eccentric portion of tard the looper relative to the upper needle.

In other words, during the last stitch-form- -ing movement the looper is thrown out of timewith.` the other elements of the stitch-- forming mechanism and the looper is thus caused to miss or skip the loop ,t of the upper thread. Hence when .the cutter is actuated there will be only the under thread and stay-cord leading from the under side of the work, both of which will be cut .close to the work. 'When the stitching'operation is started-on the next buttonhole the looper is automatically returned to its' normal positionin proper timed relation with the up.

per needle because the startingof the stitch ing operation` involves shifting the actuator rod 42 to carry the belt onto thefast pulley, and this movement of lthe actuator rod carries rthe arm 87 laterally out of engagement with the arm 86. The rod 82 is acted g.

upon by'a springlOO which tends to force it downwardly, and, therefore, as soon as the arm 83 has been released from its en'f gagement with the arm 87, the spring 100 will return the looper to its proper position.v

'last loop of upper thread, and while I have illustrated herein a selected embodiment of my invention, I do not wish t'o be limited to the construction'al features shown.

The means herein shown for holding and gripping the under thread and for severing it close to the work are not claimed herein as they form the subject matter of my abovementioned co-pending application Se. No. 206,215, of which this is a division.

isesae I claim:

l. In a sewing machine, the combination with work-holding means, of stitch-forming mechanism comprising upper-threadhandling mechanism and under-thread-handling mechanism, means to givel said stitchforming mechanisma series of stitch-forming movements and then bring it to rest, means to prevent the interlocking of the upper and under threads during the last'stitchforming Imovement, and means to cut the under thread beneath the work at pletion of the stitching operation.

2. In a sewing machine, the combination with work-holding means, of stitch-forming mechanism comprising upper-threadhandling mechanism and under-thread-handling mechanism, the latter havin provision for delivering a stay-cord to tie work as the stitches are formed, means to give said stitch-forming mechanism a series of stitch-forming movements and then bring it to rest, means to prevent the interlocking of the upper and under threads during the last stitch-forming movements of the seand means to cut the under thread and stay cord beneaththe work at the completion of the stitching operation.

3. In a sewing machine, the combination with work-holding means, of stitch-forming mechanism comprising upper threadhandling mechanism and under-thread-handling mechanism, means -to give said stitchforming mechanism a series of stitch-forming movements and then bring it to rest,l means to prevent the interlocking of the up-` per and under threads during the last stitchforming movement, and a device on' the work-holding means to cut the under thread beneath the work at the completion of the stitching operation.

Li. In a sewing machine, the combination with work-holding means including a clamp plate for supporting the work and .work clampsto clamp the work thereagainst, of stitch-forming mechanism comprising 'upper-thread-handling mechanism and underthread-handling mechanism, means to give said stitch-formingmechanism a series of stitch-forming movements and then bring it to rest, means to prevent the interlocking of the upper and under threads during the last stitch-forming'movement of the series,.and means carried by the -clamp plate to cut the under thread beneath the work.

5. In a sewing machine, the combination with work-holding means yincluding a clamp `plate for supporting the work and workI ing. provision for delivering a stay-cord to the work as the Istitches are formed, means to give said stitch-forming mechanism a the comseries of stitch-forming movements and then bring it to rest, means to prevent the interlocking of the upper and under threads during the last stitch-forming movement of the series, and means carried by the clamp plate to cut the under thread and stay-cord beneath the work at the end ofthe stitching operation.

v6. In a sewing machine, the combination with work-holding means, of stitch-forming mechanism comprising upper threadhandling mechanism and under-thread-handling mechanism, means to give said stitchforming mechanism a series of stitch-forming movements and then bring it to rest, meansl for producing a relative movement between the work-holding means and stitchforming mechanism. both during the stitchforming movements and after the stitchforming mechanism has been brought to rest, means 'to prevent the interlocking of the upper and under threads during the last stitch-forming movement of the series, and

vupper and under threads and including loop-engaging means beneath the .work for engaging the loops'of upper thread, means to give said stitch-forming mechanism a series of-stitch-forming movements, means to render the loop-engaging means inoperative during the last stltch-forming movement of the series, and means to cut the under thread beneath4 the work at the end' of the stitching operation.v

8. In a sewing machine, the combination with work-holding means, of stitch-forming mechanism `constructed to concatenate upper and under threadsv and including loop-engaging means beneath the work for engaging the loops o upper thread, means to give said stitch-forming mechanism a series of stitch-forming movements, means to render `the loop-engaging means inoperative during the last stitch-forming movement of the series, and means carried by the Workholding means to cut' the under thread beneath the work at the endV of the stitching operation.

9. In a sewing machine, the combination j with work-holding` means, of stitch-forming mechanism constructed to concatenate loops of upper and under threads and comprising a needle to insert loops of needle thread through the work, and a looper operating beneath the work to. take the loops of needle thread as they are inserted through thework, -means to give said mechanism a series of stitch iforming movements, and means to retard the action of said looper relative to that of the needle during the last stitch-forming movement of the series so with Work-holdingmeans, of stitch-forming'` mechanism constructed to concatenate loops of upper and under threads and comprising a needle to insert loops of needle thread through the Work and a looper operatingI beneath the work to take the loops of needle thread as they are inserted through the work, means to give said mechanism a series of stitch-forming movements, a stop motion to bring the stitch-forming mechanism to rest at the end of the stitch-forming movements, and means actuated by the stop motion to prevent the interlocking of the upper and under threads during the last stitch-forming movement of the series.

ll. In a sewing machine, the combination with Work-holding means, of stitch-forming mechanism constructed to concatenate loops of upper and under threads and comprising a needle to insert loops of needle thread through the work and a looper operating beneath the Work to take the loops of needle thread as they are inserted through the work, means to give said mechanism a series of stitch-forming movements, a stop motion to bring lthe stitch-forn'ling mechanism to rest at the end of the stitch-forming movements, and means actuated by said stop motion to retard the action ofthe looper during the last stitch-forming movement thereby to prevent it from engaging the loop of upper thread.

l2. In a sewing machine, the combination with Work-holding means,-of stitch-forming mechanism constructed to concatenate loops loops of upper thread, means to give said mechanism a series of stitch-forming movements, means to retard the `action of said loop-engaging-means during the last stitchforming movement of the series so as to cause it to fail to engage the loop of upper thread, and means to cut the under thread beneath the Work at the end of the stitching operation.

13. In a sewing machine, the combination stitch-forming mechanism to rest at the end of the stitch forming movements, yand means actuated by the stop motion to prevent the interlocking of the upper and'unvder threads during the last stitch-forming 'movements of the seriesand means to cut the under thread beneath the work at the end of the stitching operation.

14. In a sewing machine, the combination with Work-holding means, of stitch-forming mechanism arranged to concatenate loops of upper and under threads and `comprising loop-engagmg means beneath the Work to engage the loops of upper thread, means including a stop motion to givev said mechanism a seriesot stitch-forming movements and then to bring it to rest, means .actuated bysaid stop motion to retard the action of the loop-engaging means during the last stitclrforming movement rthereby to prevent it from engaging the loop of upper thread, and means to cut the under thread beneath the Workat the end of the stitching operation.'

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

FRANK ZALESKL

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