US2940406A - Two thread chain stitch sewing machine - Google Patents

Description

June 14, 1960 N. MARFORIO TWO THREAD CHAIN STITCH SEWING MACHINE Filed Feb. 26, 1957 Fig. 1

5 Sheets-Sheet l June 14, 1960 N. MARFORIO 2,940,406

TWO THREAD CHAIN STITCH SEWING MACHINE Filed Feb, 26, 195'? 5 Sheets-Sheet 2 r 8 Fig.2

June 14, 1960 N, -0mg 2,940,406

TWO THREAD CHAIN STITCH SEWING MACHINE Filed Feb. 26, 1957 5 Sheets-Sheet 3 F iq. 4 9

June 14, 1960 N. MARFORIO TWO THREAD CHAIN STITCH sswmc MACHINE Filed Feb. 26, 1957 5 SheetsSheet 4 it i June 14, 1960 N. MARFORIO 2,940,406

TWO THREAD CHAIN STITCH SEWING MACHINE Filed Feb. 26, 1957 5 Sheets-Sheet 5 United States Patent TWO THREAD CHAIN s'rrrcn SEWING MACHINE Nerino Marforio, Milan, Italy, assignor to S.p.A. Virginia Rimoldi & C., Milan, Italy Filed Feb. 26, 1957, Ser. No. 642,442

Claims priority, application Italy Aug. 3, 1956 e 2 Claims. (Cl. 112-197) This invention relates generally to sewing machines and specifically to improvements in two thread chainstitch sewing machines for adapting these machines for attaching fabric bands and strips in the manufacture of outer knitted garments.

A principal object of the invention is to provide an improved machine capable of carrying out at an extraordinarily increased speed in an operation or step preparatory to linking or a like operation which had to be carried out heretofore on low speed machines at high cost and required the use of skilled operators, for carrying out the step.

An object of the invention is to provide an improved machine having a special guide system through which finishing ribbed edges or fabric strips can be attached to knitted garments at a speed of about 4000 stitches per minute as against 250 stitches per minute on the known knitted fabric sewing or linking machines.

Another object is to provide a special guide system by which it is possible to position and move along the folded fabric strip in an automatic manner.

Still another object is to provide a machine capable of eifecting substantial savings through elimination of the preparatory step and lower cost of installation and operation of the machine, inasmuch as the improved machine'is less expensive than a linking machine, requires less skilled operators and performs a similar operation in a shorter time.

The characteristic features of the machine willbe understood from the specification and appended claims and as described in the accompanying drawings in which:

Fig. 1 is a perspective view of a double chain stitch sewing machine which has been adapted in accordance with the invention,

Fig. 2 is a fragmentary detail view on an enlarged scale of the machine shown in Fig. 1,

Fig. 3 is an elevational view of a structural detail of the machine shown in Figs. 1 and 2,

Fig. 4 is an end elevation view of the structure shown in Fig. 3 as viewed from the lefthand end of the structure,

Fig. 5 is a plan view of the structure shown in Fig. 3,

Fig. 6 is a plan view of a needle plate of the sewing machine in accordance with the invention,

Fig. 7 is a lefthand end view of the needle plate shown in Fig. 6, with the plate shown in a vertical position only for purpose of accommodating it in the drawings,

Fig. 8 is a perspective, exploded view of the needle plate shown in Fig. 6 and is illustrative of the assembly of the needle plate,

Fig. 9 is a side elevation view of a presser foot of the machine in accordance with the invention,

Fig. 10 is a sectional View taken on line X-X of Fig. 9, i

Fig. 11 is a plan view of the presser foot shown in Fig. 9,

2,940,406 6 Patented June 14, 1960 Fig. 12 is a sectional view taken on line XII--XII of Fig. 10,

Fig. 13 is a fragmentary perspective view of a ribbed band or finishing strip suitable for use of the machine and illustrates the folded position in which the workpiece is guided through the machine,

Fig. 14 is a fragmentary perspective view illustrative of the manner in which the workpiece shown in Fig. 13 is stitched to a garment according to the invention,

Fig. 15 is an enlarged view of the stitch pattern used in Fig. 14,

Fig. 16 is a fragmentary perspective view illustrative of a backing strip for attachment to a knitted garment,

Fig. 17 is a fragmentary view partly in section of the strip guide system according to the invention and illustrates the manner in which the elements forming the guide system cooperate to carry out the guiding function according to the invention,

In accordance with the drawings a double chain stitch sewing machine M is provided with a plate 1 having apertures or holes 1a for securing it to a tiltable cover member K, with machine screws 1b in the manner shown in Fig. 1. The machine has a vertically operable needle bar B for reciprocably operating a needle C and a pressor bar 'H'disposed substantially parallel to the needle bar spaced therefrom in a direction of advancement of 'a workpiece as later herein described.

Plate 1 is provided, at an offset portion 10 thereof as shown, with a pivot screw 2 and washer 3 providing a pivot for a rocker arm 4 having a stepped profile and provided with a longitudinal slot 5 (Figs. 2, 3 and 5) for guiding a slide 6 extending transversely of the rocker arm 4. The arm extends in length from its pivot point to edge 1d of plate 1. The slide 6 can be moved the full length of the slot 5 and locked in a set position by a knobbed member 8. The slide 6 has fixed thereto a bearing or guide plate 7 extending vertically to rocker arm 4 and having a side surface substantially facing the needle bar B and presser bar H, and functioning in the manner later herein set forth.

The rocker arm 4 may be angularly positioned to a fine adjustment by an eccentric washer 9 abutting the arm and rotatably pivoted on a pivot 10. A needle plate '11 is provided and has a portion 11a and a narrower portion 115 extending parallel to portion 11a and a part thereof, extending longitudinally therefrom and constituting a portion of the needle plate farthest removed from the needle and presser bars. The portion 11b is provided with an angular member 12 extending laterally from a longitudinal edge 11s of the portion 11b parallel to portion 11a as shown in Fig. 6 and having an upper surface thereof substantially flush with the upper surface of the plate 11. The longitudinal edge 112 is normal to a transverse axis of the plate portion 11a. Portion 11a of plate 1.1 is provided with a slot 13 through which the needle can pass during a stitching operation and is further provided with a bevel surface functioning in the manner later herein set forth. The portion 11a has a longitudinal edge 11d parallel to a longitudinal edge 11; of portion 11b. The edges lie and Hi are parallel to each other.

The invention comprises a presser device (Figs. 9 through 12) constituting a support member 14 having a split clamp 15 which can be taken up with a screw 16 for releasably clamping the presser foot device on the presser bar H. The device comprises a presser foot 17 having a slot 17a corresponding in position with the slot 13 of the needle plate for allowing the needle to move therethrough in carrying out a stitching operation in the manner set forth hereinafter.

The presser foot 17 is pivotally secured to support 14 by a threaded spindle 18. An auxiliary presser foot 19 is provided bearing on portion 11b of the needle plate and is "secured by a pin 20 to a'plunger 21 movable upwardly and downwardly in a carriage 17'and constantly biased in atdownwardd c'tionby a spring 23 having .one'

disclosed hereinafter.

. As stated heretofore, the present invention .is intended for adapting a double chain stitch sewing machine to carry out the stitching of a finishing strip or band for. ex-r ample, a 'ribbedknitted strip 24' (Fig. 13) intended to be attached to an edge of a knitted article of wear to serve has a vertical portion 19b forming a guide surface as a vice secured to a lower end of said presser bar, a guide mechanism for guiding a folded strip'workpiece to be stitched as trimming on a garment comprising, in combination, a needle plate having a first portion provided with a slot for the needle to move therethrough during a stitching operation, said needle plate having a narrower projecting second portion ravage part thereof extending longitudinally frornsaidfirst portion and. having parallel longitudinal edges substantially normal to the transverse axisof the first portion; said projectingportion' constituting a'portion of the needle plate farthest removed from the presser bansaidfirst portion having. a. longitudinal l edge parallel to the lc'ingitudinal edges'of the second poras .trimming,'for instance, for'the neck, or arm-hole,or

bottomedge of the knitted garment or article of wear. The ribbed band is manufactured, for example, on straight or circular knitting machines (not shown) with a ribbed knit ratio of 1 /1, or 2/1 or some similar ratio andis utilized any time a soft and flexible fabric is required. An 'edge 24b thereof is finished by a selvedge during manufacture and edge 240 is not in order to leave a separating thread when knitted on the straight or circular knitting machines. In order to attach the strip 24 it is folded at fold lines 24a. A lower fiap 25 is bent inwardly into the folded strip 24. This flap 25 has a maximum width c,

of one centimeter. 'It being understood that the width of the upper flap or portion MN is equal to the width of the flap or portion 'XY so that the strip is uniform and sym metrical in dimensions.

The strip 24 is fed longitudinally'automatically by the machine (Fig. 17) for securing to a garment 26 with flap 25 held under a lower surface of member 12 and 'the folded edge bearing on plate 7. The top flap MN of tion of theneedle plate, an angle member secured extending transversely to said,needleplateprojecting laterally from a longitudinal edge of said projecting portion of said needle plate parallelto said first portion, and having an upper fiat surface'substantiallyflush with the upper surface of said needle plate, a second pla'te'disposed substantially normal to the needle plate and having an end edge. aligned with the longitudinal edge of said first portion ofthe'needle plate which'is disposed nearest to it and arranged at a level lowerthan the needle plate, said second plate having opposite end portions, one of said opposite end portionsbeing disposed remote from said needle plate offset from thefopposite end portion thereofgand disposed at a higher level than thelast-mentioned opposite end portionand at a level lower than the needle plate, a rocker arm of stepped profile pivotally secured to said offset portion and extendjngtowardsaid needle plate, pivot means pivot-ally mountingsaid rocker arm'on said offset portion providing a pivot point about strip 24'enters a channel formed between guide plates 7 and 1912 with member 19a underlying the upper flap thereby to hold the flaps spaced to allow an edge of a garment the' invention. It being understood that presser foot 17 26 to be disposed in the folded strip 24 in the manner also underlies the upper flap of strip 24 in the manner shown with surface 170 smoothlyfunctioning to assist in separating the flaps; It can be seen that an edgeflb of plate 1 is substantially in the same vertical plane and aligned with longitudinal edge 11d of needle platell with the plate 1 being disposed at a lower level than the needle plate 11. In this manner the aforementioned elements form a guide system for guiding the strip 24 in folded relationship during a stitching operation.

If a stiffer-fabric is required to serve as a backing or support a strip 28 folded at 28a with selvedge at both edges 28b may be provided and sewn to a knitted article 29 by means of stitches such as 27. It being under:

stood that the guide system functions in a similar manner with respect to strip 28 as described with respect to strip or band 24. a

While a preferred embodiment of the invention has been shown and described it will be understood thatmany modifications and changes can be made withinrthe scope of the invention. What I claim'is:

said needle bar disposed spaced from the needle bar in a direction corresponding to. a direction of advancement of IA In a. two thread chain stitch sewing machine having a ,a vertically operable needle bar for operating a needle secured thereto, and arpresser bar substantially parallel to stantially equalling the distance between the pivot point said support for bearing on said portion of said needle plate provided with saidslot, said presse'r footihaving a slot corresponding to thefirst mentioned slot forthe needle to move therethrough in carrying out a stitching operation, an auxiliary presser foot pivotally supported by said presser foot about an axis'substantially parallel to an axis about which said presser foot rotates with respect to said support and displaceabl'e in a vertical direction, said auxiliary presser foot being disposed to bear on the portion of said needle plate to which said angle member is secured and having a vertical surface ,coopcrating with said vertical'bearing plate to effectively guide said workpiece longitudinallythroug h' said guide mechanisms, a lateral extension'oii said auxiliary presser foot disposed spaced above-and in correspondence-with said angle member secured to the needle plate and substantially equal inleng'th to said angle member.

7 2. A two thread stitch sewing machine according to' claim 1, in which-an'eccentric washer is rotatably secured to said secondplatesupporting the said arm rocker abutting =an edge ofsaid arm and positionable in'sele'cted angular positions for providing a'fine adjustment of theangular position of the arm. r a

References the'lfile of this patent" UNITED STATES PATENTS 1 Feigenbaumt May 11, 1948

Images