US2915996A

US2915996A - Sewing machine

Info

Publication number: US2915996A
Application number: US559002A
Authority: US
Inventors: Charest Maurice
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-01-13
Filing date: 1956-01-13
Publication date: 1959-12-08
Anticipated expiration: 1976-12-08

Description

Dec. 8, 1959 M. CHAREST 2,915,995

SEWING MACHINE Filed Jan. 1:5, 1956 4 Sheets-Sheet 1 INVENTOR Maurice Cl/AAfJT ATTORNEYS Dec. 8, 1959 M. CHAREST 2,915,996

SEWING MACHINE Filed Jan. 13, 1956. 4 Sheets-Sheet 2 INVENTOR Maurice C/IA 12557 ymmys Dec. 8, 1959 c s 2,915,996

SEWING MACHINE Filed Jan. 13, 1956 4 Sheets-Sheet 3 mvmon Maurice CHARIJT a 2216 BY W ATTORNEYS Dec. 8, 1959 M. CHAREST 2,915,996

SEWING MACHINE Filed Jan. 13, 1956 4 Sheets-Sheet 4 INVENT OR Hear/re 6 /140557- ATTORNEYS United States Patent SEWING MACHINE Maurice Charest, Montreal, Quebec, Canada Application January 13, 1956, Serial No. 559,002 2 Claims. Cl. 112-422 The present invention relates to sewing machines and more particularly to sewing machines for producing a stitch similar to U.S. Standard Stitch Type No. 606.

The general object of the present invention is the provision of a sewing machine for producing the above mentioned stitch and which at the same time attaches a strip or tape by means of said stitch.

U.S. Standard Stitch Type No. 606 is formed of three groups of threads, namely four needle threads running in four spaced parallel lines, four looper threads having portions diagonally extending between the needle threads underneath the fabric, and one cross thread extending across and joining the needle threads above the fabric. Such a stitch is used mostly for making a seam between two edge abutting pieces of material, said seam covering a substantial portion of said edges and making a flat seam which prevents unravelling of the edges of the fabric. This type of seam is mostly used for joining together pieces of tricot material such as underwear garments.

It is common practice to cover or hide such a seam by means of a tape or strip sewn thereover to reinforce said seam and impart a better appearance to the same.

According to present day practice, this strip is stitched by a separate operation after the seam has been completed. Therefore, to make a seam of the U.S. Standard Stitch Type No. 606, one needs a first machine which utilizes nine threads and a second machine for attaching the tape by means of two additional rows of stitches in all requiring four threads. The above operations are time consuming and they are expensive because arelatively large quantity of thread is used.

The sewing machine, according to the present invention, by combining in one operation the stitch of the type above mentioned together with the attachment of a tape will produce the completed scam in a much shorter period of time and will use less thread because the tape itself will be substituted for the cross thread above mentioned and will be secured by the four needle threads and, therefore, the two additional rows of stitches previously used for attaching the tape, will no longer be required.

The sewing machine, according to the present invention, is a modification of a sewing machine for producing the U.S. Standard Stitch Type No. 606, such as the so called fiat lock sewing machine manufactured by Wilcox and Gibbs Sewing Machine Company of New York, U.S.A.

The sewing machine of the present invention is capable of sewing a tape or a straight or bias strip of any type of fabric including elastic.

The foregoing and other important objects of the present invention will become more apparent during the following disclosure and by referring to the drawings in which:

Figure 1 is an exploded perspective view of the modified presser foot according to the present invention;

Figure 2 is a plan view of said presser foot with some of the parts removed;

Figure 3 is a bottom view of the same;

Figure 4 is a longitudinal section of the presser foot;

Figure 5 is a partial diagrammatic perspective view of some of the elements of the machine together with the seam being formed; V

Figure 6 is a cross-section of the completed seam taken along line 6-6 of Figure 5; i

Figure 7 is an elevation of the tape guiding and folding member; I

Figure 8 is a rear view'of said member;

Figure 9 is a longitudinal section along line 9-9 of Figure 8; I

Figure 10 is a cross-section along line Figure 7; i v

Figure 11 is a cross-section along line 11-11 of Figure 7;

Figure 12 is a partial perspective view showing the loopers, the needles and the loop spreader shown in their respective positions;

Figure 13 is an elevational view of the same elements inthe first step of the formation of the stitch;

Figure 14 is a similar view in the second step of the stitch formation;

Figure 15 is a similar View of the third step of the stitch formation;

Figure 16 is a partial perspective view of the looper, a needle and the loop spreader in the fourth step of the stitch formation;

Figure 17 is a partial perspective view of the needles and loop spreader in a fifth step of the stitch formation;

Figure 18 is a perspective view, seen at another angle, of the elements shown in Figure 17'; i

Figure 19 is a perspective view of the same elements at a completion of a stitch; H

Figure 20 is a perspective view of the stitch just completed and of the start of the next stitch; and

Figure 21 is a perspective view of two successive stitches.

Referring now more particularly to the drawings in which like reference characters indicate like elements throughout, the presser foot, according to the present invention, is clearly shown at A. It consists in a main body 1 having a bore 2 for attachment of the presser foot to the presser foot bar of the sewing machine (not shown). The presser foot is provided with two spaced

fabric engaging toes

3, 3 provided with spring blades 4.

At the base of the body 1 there is formed a transverse slot 5 through which four stitching needles 6 are adapted to pass during their up and down reciprocating movement. The needles 6 are secured to the needle bar 7, as shown in Figure 4.

As in the conventional machine above mentioned, the presser foot, according to the present invention, may be provided with the cross thread hook 8 and the cross thread carrier 9, which are reciprocated in a transverse movement by means of a lever 10 and the linkage consisting of spindle 11, arms 12 and 13, and spindle 1-4. The lever 10 is actuated by means (not shown) to reciprocate the hook 8 and carrier '9, so as to stitch the cross thread in a zig zag manner transversely of the seam. Thus the presser foot, according to the present invention, may form the U.S. Standard Stitch Type 606 by means of nine threads; but when attaching a tape at the same time as making the stitch, the cross thread may be dispensed with and, therefore, the elements 8 to 14 inclusive may be omitted. Except in Figure 1 of the drawings, said elements have been omitted as they do not form part of the invention.

The presser foot A is provided with the

usual trimmer blades

15 and 1 6. The elongated blade 15 is clamped in a slot 17 by means of a set screw 18 in the left toe 3 of the presser foot A, while the blade 16 is mounted for reciprocating movement within a slot 19 of the right toe 3, The blade 16 is provided with a small cutting edge 20 adapted to enact with the cutting edge 21 of the stationary blade 15, so as to cut the marginal portions of the two pieces B and B of the fabric fed to the presser foot, as shown in Figures 1 and 5, whereby the cut edges of said fabric pieces B and B will be in close edge abutting contact after leaving the trimmer blades. The movable blade 16 is actuated bymeans not shown.

The right toe 3 is provided with an integral upstanding block 22, which is provided at its top face with a dovetailed groove 23, which has its axis parallel with and laterally offset from the'longitudinal axis of the presser 'foot A. The groove 23 is adapted to receive the dovetailed tongue 24 of a block 25, on which is mounted the tape folder and guide 26 and the fabric bafiie 27. The tape folder 26 is maintained in inclined position laterally offset from the block 25 by means of a sheet metal piece 28, which has fingers 29 and 30 welded or otherwise secured to the back of the tape folder 26. The sheet metal piece 28 is removably attached to the block 25 by means of a set screw 28'.

The bafile 27 consists in a curved portion 27 integrally. depending from an L-shaped portion 27 which is welded to and contacts two faces of the block 25 and forms a skirt downwardly projecting from the block 25 to form an abutment 27" adapted to abut against the block 22 of the toe '3' when the block 25 is in proper position. The baffle 27 serves to reject at the side of the presser foot A the marginal portions of the fabrics B and B which have been cut off by the

trimmer blades

15 and 16.

The baffie portion 27' is provided with a depression 32 at. (Fig. l) at its inner face and along the middle portion of its top edge. Said depression allows the tape C, shown in dot and dash lines in Figure 4, and which passes through the tape folder 26, to come into smooth contact with the baffle.

The construction of the tape folder 26 is more particularly shown in Figures 7 to 11 inclusive. The folder 26 consists in a tapered sheet metal piece 33 which is inwardly bent along its side edges to form tape folding portions 34 which are joined at the lower end of the folder 26 by means of the weld 35. As clearly shown in Figure 8, the inlet end 36 of the tape folder 26 has substantially the width of the tape C, while the outlet end 37 of said folder 26 has a substantially smaller width corresponding to the folded tape, which is shown as C in Figure 7. The top edge of the folder 26 forms an outwardly curved flange 38 to guide the tape without friction into the inportion extending within the folder 26 and is adapted to I engage the tape C between the main body thereof and the folded marginal portions thereof, in order to prevent creases from forming in said folded tape. The tongue 39 is provided at its top end with side lugs 40 welded or otherwise secured to the outer face of the top ends of the folding portions 34 of the sheet metal piece 33. The tongue 39 extends downwardly from said lugs 40' on the outside of the tape folder and provides an outwardly curved portion 42, followed by an inwardly directed portion 43, which enters the tape folder between the edges of the folding portions 34 and extends within said folder at a progressively decreasing distance from the inner face ofthe portion 33 of the folder. The outer lower end of the tongue 39 projects from the outlet 37 of the folder as shown at 45. Thus the. main body of the tape is pressed between the inner face of the folder and the tongue 39 in the lower portion of the folder.

In order to facilitate feeding of the tape at the start of the sewing operation, the tongue 39 is provided with a central longitudinally extending slot 46 terminating short of the ends of said tongue. A needle or other pointed object may be inserted through the slot 46 to engage the tape and pull the same downwardly through the folder 26.

As shown in Figure 7, the folder is laterally offset from its supporting block 25 so as to be longitudinally aligned with the needles 6 of the sewing machine and also with an elongated transverse slot 48 made in the base of the presser foot A, intermediate the needle slot 5 and the

trimmer blades

15 and 16. This slot 48 is clearly shown in Figures 1, 3 and 4. The tape C emerging from the tape folder 26 passes through the slot 48 and extend under the presser foot A directly on top of the fabric where it is sewn to the adjoining pieces of fabric B and B by the needles 6, as shown in Figure 5.

The fabric and tape are pressed against the feed or take-up shoes (not shown) of the sewing machine by means of an auxiliary spring-urged foot 49, shown in Figure 4, which is mounted for vertical slidable movement Within a bore 50 of the presser foot A and is urged downwardly by a spring 51. A set screw 52 is threaded within the auxiliary foot 49 and projects through a slot 53 made in the presser foot A to limit the movement of the auxiliary foot 49.

In order to prevent the tape C from unfolding when passing through the slot 48 there is provided within said slot a cross bar 54 which contacts the underface of the folded tape and causes the same to travel through a curved path which consists in an upwardly directed bend 55, a downwardly directed bend 56, followed by another upwardly directed bend '57 at the outlet end 58 of the slot 48.

The formation of the stitch, according to the present invention, is illustrated in Figures 12 to 21 inclusive. Underneath the work plate D which supports the work, there is provided four

loopers

59, 60, 61 and 62, each associated with a needle 6 and each consisting in an elongated horizontally extending finger provided with a thread hole 63 at its outer free end and a thread hole 64 at its inner end for feeding the looper threads 65. The loopers 'less elliptical path, the long axis of which is substantially perpendicular to the plane containing the four needles 6. A loop spreader 66 is disposed underneath the work plate D and faces the free ends of the loopers 59 to 62 inclusive and is actuated by suitable means (not shown) to make a limited angular movement transversely of the loopers. The loop spreader 66 is provided with teeth 67, as shown in Figure 18, engageable with the looper threads 65 at certain stages of the operation as will be described hereinafter.

The stitches are made by two roups of four threads namely, the

needle threads

68, 68', 68" and 68", and the

looper threads

65, 65, 65" and 65'. Referring to Figure 13, each needle thread 68 is formed into a loop by the needle 6 which moves downwardly through .a slot 69 made in the work plate D and the loopers 59 to 62 move with the looper threads 65 to engage the loops of the needle threads, as shown in Figure 13. The

portions

70 and 71 of the needle threads '68 and looper threads 65 respectively are extended from the preceding stitch (not shown). The loopers and the needles make their respective forward and upward movements (Figures 14, 15) until the looper threads are eventually engaged by the teeth 67 of the loop spreader 66. The loop spreader then accomplishes its transverse angular movement, as shown in Figure 16, while the needles 6 again move downwardly between the looper threads, as shown in Figures 17 and 18. Then, the loop spreader 66 makes its return angular movement thereby disengaging the looper threads 65 which wrap themselves around the needles, as shown in Figure 19.

Figure 20 shows a completed stitch and the forming of a succeeding stitch by the needles and loopers. Figure 21 is a perspective view of two successive completed stitches. The arrow 72 shows the direction of successive stitch formations. For clarity, in Figure 21, the tape C and the fabrics B and B are not shown. The loops of the

needle threads

68, 68', 68" and 68" are passed through the tape C and the fabric pieces B, B at a predetermined distance apart transversely of the tape C. The loops of the needle threads 68 and 68' pass through a loop of looper thread 65, which extends from the last preceding stitch. The loops of

needle thread

68 and 68" pass through loops of looper threads 65' and 65" which also extend from the last preceding stitch. Finally, the needle threads 68" and 68" form loops which pass through the loop of the looper thread 65".

Thus, the seam, according to the present invention, completely covers both faces of the margins of the abutting pieces of fabrics B and B. The tape C covers completely the marginal portions of said pieces of fabrics and is securely stitched by the parallel needle threads 68, while the looper threads 65 to 65 inclusive, underneath said pieces of fabric have diagonally extending portions and transverse portions which positively prevent unravelling of the stitches and of the edges of the pieces of fabric.

The seam as above described does away with the top zigzagging thread normally found in the US. stitch type No, 606, said thread being replaced by the tape according to the present invention which imparts to the seam a much neater appearance and makes the stitch and seam much stronger in use.

Therefore, according to the present invention, stitch type No. 606 is made in a single operation with the stitching of a tape for covering said stitch.

While a preferred embodiment according to the present invention has been illustrated and described it is understood that various modifications may be resulted to without departing from the spirit and scope of the appended claims.

I claim:

1. In a sewing machine, the combination with a presser foot having a base provided with a slot for the passage of sewing needles and trimmer blades disposed on said base forwardly of said slot, of a strip guiding member mounted on said base and of an additional slot in said base intermediate said trimmer blades and said first named slot, said strip guiding member being aligned with said additional slot, and adapted to feed a strip thereinto.

2. In a sewing machine, the combination with a presser foot having a base provided with a slot for the passage of sewing needles, two spaced toes forwardly projecting from said base and trimmer blades mounted in said toes for cutting off materials fed between said toes and underneath the same, of a strip guiding member removably mounted on one of said toes, and of an additional slot in said base intermediate said trimmer blades and said first named slot, said strip guiding member being laterally offset from the toe on which it is removably mounted to be aligned with said additional slot and with said sewing needles, and adapted to feed a strip into said slot.

References Cited in the file of this patent UNITED STATES PATENTS Berger Mar. 9, 1920 202,303 Trowbridge Apr. 9, 1878 560,296 Levy May 19, 1896 705,472 Steward July 22, 1902 839,706 Bewsic Dec. 25, 1906 947,506 Weinbach et a1. Jan. 25, 1910 1,467,626 Tucker Sept. 11, 1923 1,607,131 Krell Nov. 16, 1926 1,733,867 Davidson Oct. 29, 1929 1,752,323 Bankier Apr. 1, 1930 1,872,769 Lewis Aug. 23, 1932 2,332,931 Riviere Oct. 26, 1943 2,588,886 Schwartz Mar. 11, 1952 2,621,618 Taylor Dec. 16, 1952 2,645,193 Chinnici July 14, 1953