US2298750A

US2298750A - Sewing machine

Info

Publication number: US2298750A
Application number: US228888A
Authority: US
Inventors: Norman V Christensen; Vesconte Harold J Le; Sauer George; Quist Oscar
Original assignee: Union Special Machine Co
Current assignee: Union Special Machine Co
Priority date: 1938-09-08
Filing date: 1938-09-08
Publication date: 1942-10-13
Anticipated expiration: 1959-10-13

Description

Oct. 13, 1942.

N. V. CHRISTENSEN ETAL SEWING MACHINE Filed Sept. 8, 1938 6 Sheets-Sheet l INVENTORS:

Norman VL'IZTLSZ'UZSHL fiagold 1 122 Wscomiz; i auer ar ms W ,n'v'omv ys.

George 747% Www A WI'I'NESSES? 7 "1/14, Aa

Oct. 13, 1942.- N. v. CHRISTENSEN ETAL 2,293,750

SEWING MAUI-ZINE Filed Sept. 8, 1938 6 Sheets-Swat WITNESSES:

Oct. 13, 1942. N. .v. CHRISTENSEN E'IIAL 2,293,750

SEWING MACHINE Filed Sept. 8, 1938 '6 Sheets-Sheet 3 L I J big 1 i i Q &

.f 2 m 3% E J i WITNESSES:

ATTORNEYS.

Geor qefiauerkflgar mist,

0% 1942- N. v. CHRISTENSEN ETAL 2,298,750

SEWING MACHINE Filed Sept. 8, 1938 6 Sheets-Sheet 5 INVENTORSi 7 Human; l L'h hsiensm, fibroid I [,e Mammy,

WAT/4V g/wm s sgs; I

Norman Vrchristensen, Chicago,rHarold.J.' Le

Vesconte, Western Springs, George Sauer, Berwynyand' Oscar Qulst, Chicago, 111.,- assignf on to Union'Special. Machine Company, 0111- cago, 111., a corporation of Illinois V Application September 8,1938, sesame. 228,888

' 13 Claims. (Cl. 1129155).

This invention relates to sewing machines; and

it has referencemore particularly to sewing machines of the-kind disclosed in U. S. Patent No. 10,354, grantedtoS. C. Blodgett, 'on December 20, 1853, capable of making seams in Which spaced needle thread loops passing through the fabric from opposite sides at opposed angles, are inter- (Fig. i) of a horizontal shaft u journaled in fixed bearings l2; l3, 14 within the hollow of the overhanging arm 3.

Slidable axially in inset bushings l and 16 on the-needle head 4 in parallel relation with the needle bar 5 is a presser bar I! with a shank member I8 at its lower end whereto a presser locked with each other at'points of intersection at the fabric surfaces, the seam having the appearance ,of an ordinary lockstitch seam when viewed from either side of the fabric. 1 The chief aim'of our invention is to extend (the usefulness .of sewing machinesof the kind referred to with a view toward making possible their continuous operation at higher speeds for attainment of correspondingly greater 7 output from them;. insuring greater'unifo'rmity in the seams produced by them; and enabling production of seams anywhere within the area of the fabric being sewed as well as'along itsedges.

One way in which theforegoing and other important advantages may be readily realized in practice will appear from the following detailed description of the attached drawings, wherein Fig. I is a view, partly in front elevation and partly in longitudinal section, of a sewing machine conveniently embodying our invention.

foot 19 is pivotally connected, see Fig.'IV. The presser foot I! is maintained in yielding engagement with the fabric F by a helical spring 20 which surrounds thepresser b'ar l'| andwhich is in compression between the bushing I5 and a fixed collar. 2! on said bar within the hollow of t the head 4. The bushing I5 is threaded into the Fig. II shows the machine in top plan with the top covers removed from its frame to expose important parts within.

Fig. 111 is a fragmentary view showing the machine in bottom plan. Fig. IV is an end elevation of the machine. Fig. V is atransverse sectional view taken as indicated by the arrows V--V in Figs. I and III.

Fig. VI is a fragmentary detail view looking as indicated by the arrows VI--VI in Fig. IV.

Figs. VII XVIII are diagrammatic views showing the cycle of stitch formation with the coacting parts cccupyingdifierent successive positions.-

As herein illustrated, our improved sewing machine has an elongate horizontal rectangular work support I with a hollow standard 2 rising from one end thereof and supporting an integrally-formed longitudinal overhanging arm 3, which, at its free end, terminates in a hollow needle head 4. Confined to reciprocate axially in a plane inclined to the vertical is a needle bar 5 which is guided in aligned bearings 6 and I set respectively into the top and bottom of the 1101- low needle head 4, and which, at its lower end,

carries a needle 8 adapted to penetrate fabric F' being sewed in the machine from above. The needle bar 5 is actuated, through a link 9, from top of the needle head '4 so that it may 'be adjusted axially to regulate the pressure of the spring 20.. The collar 2| has a lateral projection Zia which extends outward through a vertical guide slot 22 in one side of the needle head 4 and so prevents rotation'of the presser bar II. By means of a verticallink 23, the collar H is coupled with one end of a lever 24 fulcrumed near its'center on a screw stud 25 projecting laterally from the overhanging arm 3, see Figs. I and II. To the opposite end of the lever 24 is connected a drop link rod 26 (Figs. I and IV) which may 'extend to a foot treadle or knee press (not illustrated) and which, upon being actuated, will cause the presser bar I! to be lifted in opposition to the spring 20 to facilitate introduction of the fabric F initially beneath the presser foot I9. A spring shown at 21 in Figs. I and IV serves to maintain the lever 24 normally in the position illustrated; and, a cam finger indicated at 28 in Figs. IV and VI is provided as an auxiliary means for lifting the presser bar l1 and at the same time locking it in raised position when desired or required.

Cooperating with the needle 8 in the sewing is a needle 29 which is adapted to penetrate the fabric Fupwardly from below. As shown in Fig. IV, the needle 29 is secured to the upper end of a bar 30 which is oppositely inclined with respect to the bar 5 carrying the upper needle 8, so that it intersects the path of said upper needle at a point P in the top surface of the work support I in entering the fabric. The needle bar 30 is confined to endwise reciprocation in spaced guide bosses 3Ia, 3Ib on a plate-like carrier 3| which is fulcrumed to oscillate about a stud 32 secured in one of a series of holes 33 in an underslung bracket 35 integrally formed with the work support I at the left hand end thereof. The lower,

needle bar 30 is connected by a link 33, with a balanced crank member 10 at the left hand end one arm 31a of a bell crank 31 free on a rock shaft 38 which is journaled at one end in the bracket 85, and at the other end in a bearing lug 39 pendant from thework support I. To the other arm 31b of the bell crank 3'! is connected the rod 48a of a strap 48 which embraces an actuating eccentric 4I on a horizontal shaft 42 extending longitudinally of the machine beneath the work support I, see Fig. I. At the left hand end of the machine, the shaft 42 is journaled in another pendant bearing lug 43 on the work support I, and at the right hand end extends through bearings 45, 48 in a downward prolongation 41 of the standard 2, below the work support I, said prolongation being closed at the bottom by a removable cover plate 48 to serve as a sump which is kept filled with lubricating oil to the level conventionally indicated in Fig. I.

The fabric F is advanced crosswise of the work support I by a toothed four-motion feed dog 58 (Fig. V) which operates upwardly through an opening I in the throat plate 52 of the machine. As shown in Fig. V, the feed dog 58 overreaches the shaft 42 and has its shank secured by a screw 53 to a feed bar 55. At its rear end, the feed bar 55 is pivotally connected to the top of a vertical arm 58 on a rock shaft 51 at the side of the machine opposite that occupied by the rock shaft 38. The rock shaft 5'! is journaled at one end in the bracket 35, and at spaced intervals in pendant lugs 58, 59 of the bed plate I, and to it is clamped a slotted arcuate arm 8|. By means of a bolt 82 adjustable along the slot of the arm 6|, one end of a link 83 is connected to said arm, I

the other end of said link being connected at 85 to the strap 56 of another eccentric 81 on the shaft 42, the pivot 85 being supported at the swing end of a lazy bar 68 swingable on a rod 89 whereof the opposite ends are fixed in the hearing lugs 58, 59. By the action of the eccentric 81, the shaft 5'! is oscillated continuously with resultant impartation of feeding movements to the feed dog 58. The throw of the feed dog 58 may be varied by adjusting the bolt 82 along the arm GI without attendant change in the timing of the feed movements since the pivotal connection 85 between the link 63 and the eccentric strap 88 is restricted to a fixed arcuate path by has its the lazy bar 88. The arcuate arm 6| center of curvature in the axis of the pivot pin 65 which constitutes the common connection between the eccentric strap 88 and the

links

63 and 68 at the time when the feed dog 58 is in its forward position, i. e., in its extreme position to the right in Fig. V. The necessary lift movements are induced in the feed dog 58 from still another eccentric I8 on the shaft 42, said eccentric being embraced by a strap II which is pivotally connected at its lower end at I2 to an underreaching arm 55a integrally formed with the feed bar 55. By the arrangement just described, the feed dog 58 is actuated in a well known manner to positively advance the fabric step by step crosswise of the work support I while opposed by the reacting pressure of the presser foot I9 from above. For the purpose of moving the lower needle 29 laterally in synchronism with the feed movements of the feed dog immediately upon having entered the fabric, in accordance with our invention, we have provided mechanism for imparting oscillatory movements to the carrier 3 I. As shown, this mechanism includes a link I3 whereof the lower end is connected at I4 to the carrier 3i, and the upper end at I5 to an arm 16 clamped to the rock shaft 38 previously referred to. Similarly secured to the rock shaft 38 75 is another arm II which at I8 is connected to the lower end of the strap rod 19 of another eccentric 88 (Fig. III) on the shaft 42.

The shafts II and 42 are connected for rotation in unison by a transmission 8| within the hollow of the standard 2. This transmission includes spur gears 82. 83 respectively on the shafts II, 42, and an intermediate intermeshing idler gear 85 which is free to rotate on a shaft 88 secured in

bosses

81, 88 at opposite sides of the standard 2. As shown, the

pinions

82, 83 comprise opposingly arranged half sections 82a, 82b, and 83a, 83b respectively which are rotatively adjustable relatively on the shafts II and 42. for wear take up. The transmission BI per se, constitutes the subject matter of a co-pending application No. 211,712, filed on June 4, 1938, by George Sauer, one of the present applicants. While either of the shafts II, 42 may be utilized as the drive shaft of the machine, we preferably employ the lower shaft 42 for that purpose, and to this end have provided it with a combined hand wheel and pulley 89. For convenience of operating the machine manually in making adjustments we have secured a hand wheel 98 to the upper shaft II, as shown in Fig. I.

Pivotally connected at 9| to a fixed bracket 92 beneath the work support I is a finger 93 which is adapted to engage and temporarily hold the thread loops thrown out by the upper needle 8 as the latter begins to recede upwardly after having penetrated the fabric F, see Fig. IV, so that the lower needle 29 may enter said loops before it has penetrated the fabric. As shown, the finger 93 has a depending arm 95, which, by

.means of a link 96 is coupled with an arm 91 on ,is coupled to another arm I8I secured to said shaft 98, see Figs. III and V. Pivoted at I82 to a lateral projection I03 on the shank member I8 to which the presser foot I9 is pivoted is a finger I 85 which is adapted to engage the thread loop thrown out by the lower needle 29 as the latter begins to recede downward, after having penetrated the fabric F, so that the upper needle 8 may enter said loops at the initiation of its down strokes. The arm I88 of the finger I85 is coupled, by means of a horizontal link rod I81 with the lower end of an arm I88 clamped to one end of a rock shaft I89, which, as shown in Fig. VI, is journaled in a lug projection I I8 at the rear side of the needle head 4. To the opposite end of the rock shaft I89 inward of the lug H8 is secured an upwardly extending arm III, which, at the top, has a pivotal connection at I I2 with the strap rod II3 of the eccentric II4 on the upper needle actuating shaft IIall as shown in Fig.

laterally to the left concurrently with its axial advancement upwardly as the feed dog, begins feeding the fabric in the same direction. At the same time the finger 93 is receding to release the thread loop of the upper needle 8 and the linger I is advancing in preparation for engaging the thread loop (not shown) of said lower needle. The several parts continue. in these movements through the positions of Fig. IX to the positions of Fig. X where the lower needle 49 has fully penetrated the fabric F and reached its highest position. In Fig. XI, the lower needle 29 has just begun to recede downward axially while still continuing in its leftward movement synchronously with advance of the fabric F. In Fig. XII, the finger I05 has entered the thread loop of the receding lower needle 29. In Fig.

XIII, the lower needle 29 has completed its lefttoward its active position. The parts thereafter continue in these movements through the positions of Fig. XV to the positions of Fig. XVI wherein the upper needle 8 has completed its downward stroke. In Fig. XVII the upper needle 8 has begun its upward stroke and the finger 93 is about to engage the thread loop of said needle. In Fig. XVIII, the upper needle 8 is about to leave the fabric and the finger 93 is holding the upper needle thread loop in readiness for the lower needle 29 to pass through it in the manner shown in Fig. VII.

Repetitions of the above cycle will obviously result in a seam like that shown in the Blodgett patent hereinbefore referred to. It will moreover be evident from theforegoing that our improved sewing machine is susceptible of continuous operation at speeds comparable with that of ordinary single needle sewing machines, and mrreover that it is not limited to seaming solely along the edges of the fabric as is the case with the machine of the Blodgett patent supra.

The length of stitch may be varied by selection between the holes 33 in the bracket 35 for placement of the stud 32 on which the carrier, 3| for the lower needle 29 oscillates, since said holes are arranged in an arc struck from 'he point P (Figs. IV and VII) at the surface If the work support of the machine in which the axial fabric-penetrating paths of the

needles

8 and 29 intersect. Thus, when the stud 32 is shifted to the right in Fig. IV, the angle ztween the link 13 and the arm IE will be decreased with attendant decrease in the amount of rocking movement imparted to the carrier 3|. Similarly, shifting the fulcrum stud 32 leftward in Fig. IV will be attended by increase inthe angle between the link 13 and the arm 16, a d hence in the rocking movement of the' ditions of adjustment of the fulcrum 32 start substantially at the point P and the increases or' decreases in movement resulting from such adJustments will be at the end of the feed stroke of said needle. In the event that extreme accuracy is required to insure intersection of the lower needle 29 with the upper needle 8 exactly at the point P, the arm 16 may be adjusted circumferentially of the rock shaft 38 to the necessary extent after transposal of the fulcrum pin32 for the guide member 3|, in a manner which will be obvious from Fig. IV.

Having thus described our invention, we claim:

1. A sewing machine comprising a work support; feeding means for engaging fabric and intermittently advancing it on the work support; a needle adaptedto penetrate fabric on the work support from above; means for actuating said needle; a second needle adapted to penetrate the fabric from below; a pivoted carrier in which the second needle is guided for axial movement; means for actuating the second needle in alternation with the first needle; and means for oscillating the carrier while the second needle is engaged in the fabric, to move said needle latorally in synchronism with the fabric advancing movements of the feeding means.

2. A sewing machine comprisinga work sup-' port; feeding means for engaging fabric and I intermittently advancing it on the work support; a needle adapted to penetrate fabric on the work support from above; means for actuating said needle; a second needle adapted to penetrate the fabric from below; a pivoted carrier in which the second needle is guided'for endwise reciprocation; a shaft journaled beneath the worksupport; means deriving movement from said shaft for reciprocating the second needle endwise as aforesaid in alternation with the movements of the upper needle; and means also deriving movement from the shaft for actuating the carrier to move the second needle laterally while it is engaged in the fabric synchronously with the fabric advancing movements of the feeding means.

3. A sewing machine comprising a work support; feeding means for engaging the fabric and intermittently advancing it on the work support; a needle adapted to penetrate the fabric from above; a shaft above the work support from which said needle is actuated; a second needle adapted to penetrate the fabric from beneath;v

a shaft below the work support from which the second needle is actuated in alternation with the first needle; meansalso actuated from the lower shaft for moving the second needle lat erally, while engaged in the fabric, in synchronism with the fabric advancing movements of the feeding means; means below the work support actuated from the lower shaft for spreading and temporarily holding the thread loop of the first needle to enable entry thereinto of the second needle; means above the work support acfabric and intermittently advancing it on the work support; a needle for penetrating the fabric from above; means for actuating the needle; a

said point. Accordingly the lateral feed move-j ment of the lower needle 29 will under all con second needle for penetrating the fabric from beneath; means for actuating the second needle; a pivoted carrier below the work support in which the second needle is guided for reciprocation in an inclined path intersecting that of the first needle in a point at the surface of the work support; mechanism for oscillating the carrier to move the second needle laterally while in the fabric, in synchronism with the fabric advancing movements of the feeding means, said mechanism including a rock shaft below the work support, a lateral arm on said rock shaft and a vertical link connecting said arm with said carrier; means whereby the pivot for the carrier can be adjusted along an arc struck from the point of intersection of the needle paths, to increase or decrease the lateral movements of the second needle compensatively with the adjustments of the feeding means.

5. A sewing machine comprising a work support; a feedingelement for intermittently advancing the fabric on the work support; means for actuating the feeding element; a pair of needles for penetrating the work from opposite sides; guides respectively determining passage of the needles through a point of intersection at the level of the work support; means for actuating the needles; means for actuating one of the guides so that the corresponding needle is shifted laterally relative to said point while in the fabric synchronously with the advance shifts of the fabric by the feeding means; and means for adjusting the feed actuating means and the guide of the laterally shiftable needle compensatively without entailing any substantial change in the position of the intersection point for the purpose of stitch length variation relative to said point.-

6. A sewing machine comprising a work support; a feeding element for engaging fabric and intermittently advancing it on the work support; means for actuating said feeding element; a pair of needles adapted to alternately penetrate the fabric from opposite sides respectively; means for guiding the needles to reciprocate axially along angular paths which intersect in a point at the surface of the work support; means for actuating the needles; means for moving the guide for one of the needles so that the path of said needle is shifted laterally, relative to the aforesaid point after the needle has entered the fabric, in synchronism with the advance shifts of the fabric by the feeding element; and means for adjusting the feed actuating means and the guide of the laterally shiftable needle compensatively to effect stitch length variation substantiallywithout attendant change in the point of intersection of the needle paths.

'7. A sewing machine comprising a work support; a feeding element for engaging fabric and intermittently advancing it on the work support; means for actuating said feeding element; a pair of needles adapted to alternately penetrate the fabric from opposite sides respectively; guides respectively for said needles determining intersection of the paths of the latter in a fixed point at the level of the work support; means for actuating the needles; actuating means for moving one of the guides to laterally shift the path of the corresponding needle while in the fabric synchronously with the advance shifts of the fabric by the feeding element; means at one side of the work support for spreading and temporarily holding the thread loop of one needle to enable entry thereinto of the other needle after the latter has penetrated the fabric; means at the opposite side of the work support for spreading and temporarily holding the thread loop of said other needle to enable entry thereinto of the first mentioned needle after the latter has penetrated the fabric; and means for adjusting the feed actuating means and the guide of the laterally shiftable needle compensatively to effect stitch length variation substantially without attendant change in the point of intersection of the needle paths.

8.'A sewing machine comprising a work su'pport; a feeding element for engaging fabric and intermittently advancing it on the work support; means for actuating said feeding element; a pair of needles adapted to alternately penetrate the fabric from opposite sides respectively; means for actuating the needles; guides respectively for the needles to determine intersection of the paths of the latter in a point at the level of the work support; means for moving one of the guides to laterally shift the path of the corresponding needle after it has entered the fabric, in synchronism with the advance shifts of the fabric by the feeding element; means at one side of the work support for spreading and temporarily holding the thread loop of one needle to enable entry thereinto of the other needle after the latter has penetrated the fabric; means at the opposite side of the work support for spreading and temporarily holding the thread loop of said other needle to enable entry thereinto of the first mentioned needle after the latter has penetrated the fabric; and means for adjusting the feed actuating means and the guide of the laterally shiftable needle compensatively to effect stitch length variation substantially without attendant change in the point of intersection of the needle paths.

9. A sewing machine comprising a horizontal work support; a feeding element for engaging fabric and intermittently advancing it on the work support; means for actuating the feeding element; a pair of opposing upper and lower needles adapted to alternately penetrate the fabric respectively from opposite sides; means for actuating the needles; guides for determining intersection of the paths of the needles in a point at the level of the work support; means below the work support for spreading and temporarily holding the loop of the upper needle after it has penetrated the fabric to permit entry of the lower needle; means above the work support for similarly spreading and temporarily holding the loop of the lower needle after it has penetrated the fabric to permit entry of the upper needle; actuating means operative to move the guide of one of the needles while engaged in the fabric to laterally shift its path synchronously with each fabric-advancing shift of the feeding element; and means for adjusting the actuating feed means and the guide of the laterally shiftable needle commnsatively to effect stitch length variation substantially without attendant change in the point of intersection of the needle paths.

10. A sewing machine comprising a horizontal work support; a shaft journaled above said work sup-port; another shaft journaled below the work support; a feeding element for engaging fabric and intermittently advancing it on the Work support; means for actuating the feeding element; a

needle adapted to penetrate the fabric from above; means for guiding the needle to pass through the work support; means whereby said needle is actuated from the upper shaft; a second needle adapted to penetrate the fabric from below; means whereby the second needle is actuated from the lower shaft in alternation with the first needle; means for guiding the second needle in a path which intersects the path of the first needle at the level of the work support; means actuated from the lower shaft whereby the guide means for the second needle is moved to laterally shift the path of the latter while engaged in the fabric in synchronism with each fabric-advancing shift of the feeding means; and means for adjust;-

ing the feed actuating means and the guide means of the laterally shiftable needle compensatively to effect stitch length variation substantially without attendant change in the-point of intersection of the needle paths.

11; A sewing machine comprising a work support; a needle; means for reciprocating the needle endwise; means for guiding the needle to pass through the work support always at the same point during its work piercing stroke; means tov cooperate with the needle in stitch formation at said point; means for moving the guide to shift the needle laterally after having penetrated the work to intermittently advance the work on the work support; and means for adjusting the guide at the same point during its work penetrating stroke; means for moving the guide to shift the needle laterally while in the fabric'in synchronism with the feeding movement of the feeding element; means to cooperate with the needle in stitch formation at said point; means for adjusting the guidefor the purpose of increasing or decreasing the lateral throwof the needle with respect to the point aforesaid in which the needle passes through the work support, to vary the stitch length; and means for adjusting the feed reciprocating means compensatively to corresp'ondingly increase or decrease the throw of the feed dog relative to a fixed point of starting.

13. A sewing machine comprising a work support; a'needle; means for reciprocating the needle endwise; a four motion feed dog; means for actuating the feed dog to intermittently advance fabric on the work support; means for guiding the needle to pass through the work support always at the same point during its work penetrating stroke; means for moving the guide to shift the needle laterally while in the fabric in synchronism with the feeding stroke of the feed dog; means to cooperate with the needle in stitch formation at said point; means for adjusting the guide for the purpose of increasing or decreasing the lateral throw of the needle with respect to the point aforesaid in which the needle passes through the work support to vary the stitch length; and means for adjusting the feed actuating means compansatively to correspondingly increase or decrease the stroke of the feed dog relative to a fixed point of starting.

NORMAN V. CHRISTENSEN.

; HAROLD J. LE VESCQNTE.

GEORGE SAUER. OSCAR QUIST.