US2155722A - Sewing machine - Google Patents

Description

April 25, 1939. F M LEE 2,155,722

` SEWING MACHINE Filed Aug. 16, 1957 4 Sheets-Sheet l lllIlIIIIIIlllllllllllllllllllllIll l o 36 Lrg BY QJ E.

ATTORNEY.

April 25, 1939. F, M LEE 2,155,722

SEWING MACHINE Filed Aug. 16, 1937 4 Sheets-Sheet 2 INVENIOR. ffefp M. ff

BY I i a ATTORNEY.

April 25, 1939. F M, LEE 2,155,722

A SEWING MACHINE Filed Aug. 16, 1937 4 Sheets-Sheet 3 Fig. 3,

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- INVENTOR.

pez@ /7 es ATTORNEY.

April 25, 1939.

F. M. LEE

Filed Aug. 16, 1957 @gli 4 Sheets-Sheet 4 O o V1 /9 ,v9 /4 if i 32 :Il 7 7 j ,FM 32 /fJa Fig. fa. JZ

75 d fj 27 23 Z@ ze INVENTOR. /A-D M- .1616

BY l l ATTORNEY.

Patented Apr. 25, 1939 PATENT. olii-ical snwmG Maennvr:

Fred M. Lee, Dearborn, Mich., assignor to American Lady Corset Company, Detroit'llich., a corporation. of lMichigan Application Anm: 1e, 1937, serial No. 159,233

12 claims.v (ci. 11a-159) This invention relates to sewing machines and more particularly to a. construction which may be considered either as a part of the machine or as an attachment therefor, the function of which is to provide for the simultaneous diagonal stitching of a`plurality of rows. The main objects of the invention are to provide a device of this character which will form stitches of uniform size, which will pull all threads against the 1| work with uniform tightness and which is therefore capable of making stitches which are substantially invisible, which will form holes in lthe work no larger than the needles, which will not skip stitches and which will accomplish these results particularly on elastic goods such as corsets, girdles, and the like.

Another object is to provide -a device for diagonal stitching in which the needle moves only in a vertical path during penetration and withn drawal into and out of the work, the lateral movements being aiected while the needle is in retracted position, and to apply this principle to a needle bar carrying a plurality of needles.

More particularly it is an object to provide a 9,5 needle bar having a head adapted to receive and maintain a plurality of needles in permanent parallel spaced relation together with means for moving the head and the needles vertically, into and out of work, and diagonally to form diagonal so stitches, the diagonal movement being accomplished at or near the top of the withdrawal stroke of the needle bar.

Another object is to provide a needle bar reciprocally journalled in a universally mounted frame in combination with a cam and yoke for causing diagonal swinging oi the frame, said cam having periods of rest for said yoke whereby the diagonal swinging occurs at predetermined periods in the cycle of movement of said bar.

o Another object is to provide a needle bar frame swingable in two directions, a needle bar reciprocal in the frame and means including a universal connection for reciprocating said bar and for eiiecting swinging movements of said frame 45 and bar. y v

Another object is to provide a plurality of bobbin cases, one 'for each of said needles together with means for shifting the cases in correspondence to the lneedles in order to form the diagonal .o stitching, `the bobbin hooks encountering the loops formed by the needles in identical fashion at every stroke thereby preventing the skipping oi stitches.

Another object is to provide hook saddles,

u hooks therefor 4and lbobbin cases carried by the hook saddles all mounted on a common support in combination with means for shifting these parts synchronously with the swinging of the 'needle bar, these means comprising gears carried by said support and shiftable therewith. 5 The movement of the hook saddles therefore does not depend on the gear movements but on means externally of the common support which is preferably a second cam formed similarly toV the cam which shifts theneedle bar frame,l as previously described. In further combination with this cam actuating means is a positive stop for the support which has the effect of making all stitches of equal size. l

A still further object is to provide a compound 18' feed for a diagonal stitch machine, the needle bar frame swinging synchronously with the feed dog, the swinging being in the direction of movement of the work during the feeding stroke and in reverse direction during periods when the dog 2o is lowered. The movement is essentially that of a single stitcher, all movement of the needle inthe work being vertical, the movement in the feeder being unidirectionau.

Other objects and advantages will hereinafter 25 become more apparent as reference is had to the` accompanying drawings wherein:

Fig. 1 is a vertical section through the bed plate of a sewing machine, taken substantially at the plane of line I I on Fig. 2, and having a head mounted thereon, partially broken away;

Fig. 2 is a vertical sectiontaken on the line 2 2 ofFig.1;

Figs. 3, 4 and 5 are enlarged sections taken on lines 3 3, 4 4 and 5 5, respectively, on Fig. 2; 35

Fig. 6 is an elevation of the bobbin saddle Spacer: Y

Figs. 'l' and 8 are sections taken respectively on lines 1 1 and 8 8 of Fig. 3;

Fig.9 is a fragmental plan illustrating the bob- 40 bin cases and their rotation preventing means;

Fig. 10 is a section taken on the line Ill-I0 of Fig. 1;

Fig. 11 is a section taken on the line Il l'l of Fig. 10; 4 Figs. 12 and `13 are sections taken respectively on lines I2 |2 and |3-l3 of Fig. 1, and Fig. 14

is a section taken on the line lH iii of Fig. 1. Fig. 15 is a top plan view of a presser foot.

The numeral I designates the bed plate "of a I sewing machine having a substantially horizontal hollow arm 2 rigidly supported thereon and held thereabove by a vertical supporting structure 3. In the end of the hollow arm 2 is a needle bar frame 4, supported for swinging movement about a horizontal pivot 5 in a direction transverse to the bed plate I. The needle bar frame 4 is formed in two sections 6 and 1 united by a hinge member 8. this member being preferably in the form of a piece of at spring steel. 'I'hev two frame sections 6 and 1 are slightly spaced whereby the section 1 is capable of swinging movement relative to the section 6 which is mounted on the pivot 5. 'Ihe direction of swinging movement of the frame section 1, relative to the frame section .6, is at right angles to the direction of` swinging movement of the frame about the pivot 5. 'Ihe frame may thus be said to be capable -of universal swinging movements. y

Bearings 9 and I8 are provided for the frame section 1 and slidably received in these bearings is a needle bar II having a head I2 on its lower extremity, this head rigidly receiving two spaced apart needles I3 and I4. The needle bar II is illustrated as composed of two parts which are permanently secured together,1 whereby they move as a single unit. 'I'his construction is for convenience in manufacture, and has no bearing on the operation of the machine. An actuating arm I6 is connected to the needle bar II by a universal joint I5 and a link I1 has one end slidably connected to the arm I6 and its other end connected to a pin I8. This pin is eccentrically mounted on a head I8 of a rotatable shaft 28. Rotation of the shaft 28 and the head I9 moves the pin I8 through a circular orbit, and the link I1, moving with the pin I6, imparts vertical reciprocatory movement to the needle bar. The means for rotating the shaft 28 is a sprocket chain 16 connecting this shaft with power shaft 33, as will be hereinafter referred to.

Fixed to the bed plate I, and extending vertically thereabove beneath the hollow arm 2, is a hollow post 2I rotatably supporting a vertical shaft 22. A cam 23 is keyed or otherwise secured upon the upper end of the shaft 22 and a yoke 24 is supported for engagement with the cam 23 by a stud 25 secured thereto and slidably mounted in a bearing 26 carried by the bracket 2| a. A flexible element 21, formed of closely coiled spring steel wire, which has one end connected to the sliding stud 25 and its other end connected to a fitting 28 on the lower end of the needle bar frame 4 serves as a motion transmitting means.

It is apparent, from the foregoing, that rotation of the shaft 22 and cam 23, as will hereinafter be described, reciprocates the sliding stud 25 which moves the flexible elemient 21 thus imparting swinging movements to the frame section 1. The universal joint between theneedle bar II and the arm I6 and the bearing connection between the spindle I6 and the link I1 permits such swinging movement of the frame section 1 while the needle bar is being reciprocated vertically through rotation of the shaft 28, as above described. 'I'he universal joint I5 and sliding connection of the spindle with the link I1 also permits reciprocation of the needle bar while the needle bar frame is being swung about the pivot 5 by the oscillating crank 28. The crank 29, which is operated in synchronism with mechanism to be hereinafter described, has a pin 38 engaging a slidable block 3| mounted in vertically extending ways 32 on the frame section 1.

Rotatably mounted beneath the bed plate I is a power shaft 33, connected to the shaft 28 by the sprocket chain 16` and driven by any suitable source of power supply (not shown) The power shaft 33 is supported in a bearing 35 coaxial with a shaft 36 and is connected thereto by the extensible connection 31, shownin Fig. 5. The shaft. extends through two hook saddles 36 and 39 which are supported with respect to the bed plate I by studs 48 extending throughslots 4I therein. 'Ihe shaft 36 may rotate relative to the hook saddle. It will be understood that the studs 48 are not clamping elements and that they permit sliding movement of the hook saddles and shaft 36. Adjacent the extensible connection 31 the shaft 36 has a groove 36a receiving a snap ring 36h. When the shaft 36 and hook saddles 38and 39 are shifted toward the right hand side, as shown in Fig. 5, the snap ring 36h contacts the side of the bearing 35 and positively restricts movement of the shaft and saddles in that direction. As is hereinafter described, a rotatable cam 55 is provided for reciprocating the shaft 36 and the hook saddles, and the purpose of the ring 36h is to overcome the inertia resulting from movement in one direction and relieve the cam to this extent. The hook saddles 36 and 38 support bobbin cases 42 and 43, respectively, and gears 44 and 45 for operating the hooks 46 and 41. 'Ihe bobbin cases and the hooks are illustrated in more or less diagrammatic fashion in Fig. 3, a detailed showing thereof not being made because the use of conventional bobbin cases and hooks is contemplated.

In sewing machines of standard or zig-zag type it is essential that the needles maintain a definite spaced relationship with the hooks. 'I'hat is, at the time the needles descend and cause a loop in the threads carried thereby they must be within a definite distance range of the hooks in order that the latter may engage the loops. For this reason the hooks 46 and 41 are driven from the power shaft 33 and gears 46 and 49 on the shaft 36. However, as above described, the needles and the needle bar II are caused to swing in the direction of the length of the shaft 36, and in order to maintain a definite relationship between the needles and the hooks 46 and 41 it is necessary to shift the hooks and their saddles in the direction of the length of the shaft 36. This means will now be described.

The two hook saddles 38 and 39, through which the shaft 36 extends, are connected for simultaneous movement by a rigid spacer 58. Two grooves, 5I and 52, are formed in the spacer 58, the walls of which engage respective gears 46 and 49 to maintain them in meshing relationship with the gears 44 and 45. Also secured to both hook saddles 36 and 39 is a rigid connecting rod 53 having a yoke 54 on the free end thereof engaging a cam 55 on the lower end of the shaft 22. Adjacent the cam 55 the shaft 22 has a gear 56 which meshes with a gear 51 on the power shaft 33. The ratio of gear 51 to 56 is as one is totwo, whereby shaft 22, rotates at one-half the speed of the power shaft 33.

Carried by the rigid rod 53 is a forked element 58 having two rearwardly extending arms 58 and 68 with notches 6I therein. The bobbin cases 42 and 43 have retainers 62 and 63 respectively which engage in the notches 6I to retain the bobbin cases from rotating. 'I'he forked element 56, being mounted on the rigid rod 53, shifts with the hook saddles. Y

'I'he feed dog 64, which moves the material being stitched, is moved in synchronism with the swinging movement of the needle bar frame relative to the pivot 5 and in order to provide for such synchronous operation the arm 65, upon which the feed dog 64 is mounted, is connected 4m Upon reference to Figs 12 and 13 it will be noted I alumna l direction whileV the needles are elevated or'abov'e the top surface of the bed plate. The feed dog supporting arm 65 has a yoke 68 thereonengaging a cam 89 on'the shaft 36 which functions to elevate the feed dog to a position slightly above the bed plate surface as it is moved in one direc.

tion by the crank 66 and to lowerlt so that'its opposite movement takes place in a plane beneath the top surface of the bed plate.

-As a means for oscillating cranks 29 and 66 in unison, the shaft 33 is providedA with an eccentric 33a which, when rotated, reciprocates'the link 33h, and oscillates thecrank 23a, the latter being connected rigidly to the crank 29. On the shaft 61 is'a crank arm 61a, and a link 61h connects this crank to the crank 29a. The two cranks 29a and 61a are of equal length and the oscillations of shafts 29h and 6,1 are, therefore, equal and in time.

In the operation of the above described mechanism it is assumedl that the shaft 33 is connected to a suitable power means for rotating thesame. The vertical shaft 22, being. geared to the shaft 33, is rotated thereby and imparts rotation to the two cams 23 and 55 which are identical. 'I'he cam 23, as above mentioned, causes swinging and the shaft 36. Inasmuch as the two cams are identical in shape the needle bar and hook saddles -move like amounts and theA distance between the needles I3 and Il, at the time the needles are in their lowermost position, is the same regardless of the swinging movement of the franle portion 1 to provide a zig-zag stitch.

that the peripheries of the cams 23 and 55 are divided into two portions and the radius of each portion is uniform. 'I'he result'of such a cam tion to the other, and that they dwell for a short period of time at each extreme. During the dwells in said movements the needles penetrate rises.

the material being worked upon and are retracted therefrom before the next movement commences.

As the needles penetrate the work the feed dog When the needles have reached the lowermost point they swing rearwardly (away from an operator) and the feed. dog moves rearwardly at the same speed. The needles travel outwardly of the work during this rearward movement and after they leave the work the feed dog travels downwardly and forwardly, coming to rest substantially before the needles again begin penetration of the work. 'Ihis is descriptive of the compound feeding. 'I'he actual movement of the needle is graphically shown in Fig. 15 which shows a top plan of a presser foot 15 having rectangular openings 10, one opening for each needle. A needle cycle is as follows: 'I'he needle penetrates the work at 1I, the work remaining stationary until the needle has reached its lowermost point of travel. The work, needle and feed dog then travel rearwardly together to the point 12, the needle rising during this travel and leaving the work when it reaches the position 12, which is near an opposite corner of the opening 10. 'While the needle is in elevated position it travels diagonally across the opening to the corner position 13 Where it again penetrates the work to its full depth, the reed dog rises, as Just described, the

needle with the dog and work travel rearwardly together to the corner position 14 where the needlel leaves the work and travels diagonally across for entry at the position 1l.

It may be stated that the presser foot 15 may be of conventional type except possibly that the openings must be suillciently large to permit v 'Ihe presser' foot the diagonal needle movements. is carried by a presser bar whichis capable of vertical movements only.

WhatI-claiin iszg 1. In a sewing machine arranged for diagonal stitching, the combination of a plurality of relatively iixed, parallel needles,'means for reciprocating said needles in unison vertically for insertion and withdrawal into and out of work,- means for swinging said needles in unison diagonally of said work to form diagonal stitches therein, means for operating said last named means when the needles are withdrawn from the work, means for moving said needles in the directionof travel of the work while the needles are inserted in the work, and means for moving the work while the needles are inserted therein.

. 2. In a sewing machine, a plurality of needles, means retaining said needles in constant parallel relation, means for reciprocating said needles vertically into and out of work, means for swinging said needles inunison diagonally of said work during the upper stage in the cycle of vertical reciprocations, means for moving the needles in the direction of travel ofthe work during the lower stage in their cycle of reciprocations, and means for moving the work during said lower stage in the cycle of reciprocations.

3. Ina sewing machine, a plurality of needles, means retaining said needles in constant parallel relation, means for reciprocating said means and said needles vertically into and out of work, intermittent means for moving work, means for swinging said needles in the direction of' and during movement of work while the needles are in the work, and means operative when said needles are entirely out of said work and while the work is stationary for swinging said needles and said retaining means transverselyv of the direction of movement thereof.`

4. In a sewing machine, a plurality of needles, means retaining said needles in constant parallel relation, means for reciprocating said means and said needles vertically into and lout of work, means for swinging said needles back and forth in the direction of movement of work and means comprising a cam and a resiliently flexible pushrod connected to said retaining means at one end and subject to motion by said cam at its other end for swinging said needles and said retaining means transverselyof the direction of movement of said work.

5. In a sewing machine, a plurality of needles, means retaining said needles in constant parallel relation, means for reciprocating said means and said needles vertically into and out of work, means for swinging said needles back and forth in the direction of movement of work andv means comprising a rotating cam, a coil spring having a cam contactor atone end and a connector for stitching, a bed plate, a plurality oi' bobbin cases, hooks and rigidly united hook saddles beneath said plate, means for reciprocating said cases,

stitching, a bed plate, bobbin cases, hooks and hook saddles.mounted beneath said bed plate,

driving means including gears for rotating said hooks. means rigidly uniting said saddles, and means for reciprocating said cases, hooks, saddles and gears transversely of the direction oi' movement of work travelling along the upper surface of said bed plate, said uniting means engaging certain of said gears to maintain the respective gears in mesh during said reciprocating movement.

8. In a sewing machine arranged for diagonal stitching, a bed plate, a plurality of hook saddles and hooks below said bed plate, means for rotating each of said hooks comprising a set of meshing gears and a common drive shaft for all of said sets of gears, means rigidly connecting said hook saddles and means for shifting said saddles, said drive shaft and said sets of gears back and forth across the direction of movement of work travelling on said bed plate.

9. In a sewing machine arranged for diagonal stitching, a bed plate, a plurality of hook saddles and hooks below said bed plate, means for rotating each of said hooks comprising a set of meshing gears and a common drive shaft for all of said sets of gears, means rigidly connecting said hook saddles and means for shifting said saddles, said drive shaft and said sets of gears back and forth across the direction of movement of work travelling on said bed plate, said shifting means comprising a cam rotating adjacent one end of said drive shaft and a yoke about said cam connected to said hook saddles.

10. In a sewing machine for diagonal stitching, a needle bar having a plurality of continuously parallel needles carried thereby, means for vertically reciprocating said bar, means for swinging said bar through a vertical arc in the direction of movement of work being stitched, means for swinging said bar through a second vertical arc transversely of the direction of travel of said aleman work. a bed plate through whichsaid needles travel after piercing said work, a hook saddle. hook and bobbin case for each of said needles mounted below said plate. said hook saddles being strapped together. and means for reciprocating said hook saddles, hooks and cases 'transversely of the direction of travel of said work in timed relation with the movements of said means for swinging said bar through said second vertical arc.

11. In a sewing machine for diagonal stitching, the combination of a plurality of needles. a retainer in which said needles are mounted, means forV vertically reciprocating said retainer, means for swinging said retainer through a vertical arc in the direction of travel of work being stitched. a feed dog movable directionally with said retainer during its work feeding stroke, means for moving said retainer transversely of the direction of travel of said work, a bed plate, a bobbin case, hook saddle and hook for each of said needles mounted below said bed plate. and means for moving said cases, saddles and hooks transversely of the direction of travel of said work in timed relation with the transverse swinging movements of said retainer.

12. In a sewing machine for diagonal stitching. the combination of a needle bar having a plurality of parallel needles carried thereby, a frame in which said needle bar is mounted for vertical reciprocations, an upper frame part. a flexible hinge member connecting said frame part and frame whereby said frame may swing through a vertical arc transversely of the direction of travel of work being stitched, a pivot upon which said upper frame part is mounted and on which said frame is swingable through a vertical arc in the direction of movement of said work, a. feed dog movable directionally with said needle bar on its work feeding stroke, a bed plate, a bobbin case, hook saddle and hook for each of said needles mounted below said plate, means for rotating each of said hooks comprising a set of gears and a shaft common to one gear of each of said sets, all of said hook saddles being strapped together, cam means for moving said cases, saddles. hooks and sets of gears transversely of the direction of travel of said work in timed relation with the transverse swinging movements of said needle bar.

FRED M. LEE. 5

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