US2046933A - Sewing machine for seaming and covering the edge portions of fabric sections - Google Patents

Description

July 7, 1936. J. BERGER 2,046,933

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS Filed Jan. 12, 1933 ll Sheets-Sheet 1 July 7, 1936. J. BERGER 2,046,933

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS Filed Jan. 12, 1953 11 Sheets-Sheet 2 July 7, 1936.

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS Filed Jan. 12, 1933 J. BERGER 2,046,933

ll Sheets-Sheet 3 July 7, 1936. BERGER I 2,046,933

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS 11 Sheets-Sheet 4 Filed Jan. 12, 1955 I I J V lIl J. BERGER July 7, 1936.

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS Filed Jan. 12, 1953 11 Sheets-Sheet 5 July 7, 1936.

J. BERGER 2,046,933-

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS Filed Jan. 12,1953

lilllll l1 Sheets-Sheet 6 m Amman hmfi J. BERGER 2,046,933

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS July 7, 1936.

ll Sheets-Sheet 7 Filed Jan. 12, 1933 Alluvial-4:

July 7, 1936.

J. BERGER SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS Filed Jan.- 12, 1935 11 Sheets-Sheet 8' July 7, 1936.

J. BERGER 2,046,933

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS Filed Jan. 12, 1953 11 Sheets-Sheet 9 J. BERGER SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS ll Sheets-Sheet 10 swam tom awm s July 7, 1936. J. BERGER 2,046,933

SEWING MACHINE FOR SEAMING AND COVERING THE EDGE PORTIONS OF FABRIC SECTIONS Filed Jan. 12, 1935 ll Sheets-Sheet l1 Patented July 7, 1936 UNITED STATES PATENT OFFICE SEWING MACHINE FOR SEAIVIING -AND' COVERING THE EDGE PORTIONS F FABRIC SECTIONS corporation of Illinois Application January 12,

so'onims.

The invention relates to new and useful improvements in a sewing machine which joins the upturned edge portionsof fabric sections and covers the same to form a flat seam.

An object of the invention is to provide a machine of the above type wherein the edge portions which have been joined by through and through stitches may be turned down prior to the covering of the same with covering stitches. v A further object of the invention is to provide a machine of the above type with trimming devices located in advance of the through and through stitching mechanism for trimming the edges preparatory to the joining of the same and the turning of the edge portions down for covering.

A still further object of the invention is to provide a machine of the above type wherein the through and through stitch forming mech- 20 anism and the trimming devices may rise and fall during the stitching operation to accommodate varying thicknesses, and for stitching the fabric sections a uniform distance from the trimmed edges.

A still further object of the invention is to provide a machine: of the above type wherein there is a presser foot associated with each stitching mechanism, and said presser feet are mounted so that the front foot cooperating with 30 the through and through stitchingmechanism may yield independently of the rear foot, and wherein the stitching mechanism for forming the through and through stitches will yield with the associated presser foot.

A still further object of the invention is to provide a machine of the above type wherein the-presser foot cooperating with the through and through stitch forming mechanism is provided with a channel or groove in its under face 40 for directing the upturned edge portions of the fabric sections, and wherein the wall' of the groove opposite the side of the fabric penetrated by the needle serves as a work supporting member;

'A ,still further object of the invention is to provide a machine of the above type wherein the presser foot' associated with the covering A-jStill further objecttof theinvention is t0 1933, Serial No. 6511A25 provide a machine of the above type wherein the covering stitching forms .a twin needle stitch so disposed that the looper thread covers the turned down edge portions, and wherein means is associated with the stitching mechanism for supporting the needle threads for chaining ofi between stitched articles.

-These and other objects will in part be obvious and will in part be hereinafter more fully described.

In the drawings which show by way of illustration one embodiment of the invention- Figure 1 is a view from the front side of the work supporting arm showing a machine embodying the improvements with certain cover plates removed to show the structure of the machine;

Fig. 2 is a view of the machine as viewed from the end of the work support, with the hand wheel removed and the cap for the front end of the work support also removed;

Fig. 3 is a plan view of a portion of the ma chine showing the end of the work support, the needle head, the parts mounted thereon and the actuating mechanism for operating the parts on the needle head;

Fig. 4 is a sectional view substantially on the line :ra: of Fig. 2, certain of the operating members being omitted for the sake of cle'arness;

Fig. 4a is a view showing more or less'diagrammatically the operating parts for the looper with the arm and link in alinement and the looper at the forward end of its stroke at a dwell;

Fig. 4b is a similar view' showing in broken lines the extent of movement of the link and arm past dead center and in full lines the posiless diagrammatically the'u'nder needle 'operatl ing mechanism, the throat plate, the presser feet and the manner of supporting the same, also showing certain parts'of the looper operating devices;

Fig. 6 is an enlargedvertical' sectional view through the work support and the parts im'me diatelyabove the sameat the linefof the through i and through stitching mechanism; i

Fig. 6a is a view showing more or lessdiaf grammatically the-looper" and the needle mar the looper at the *forward end of its stroke;

Fig. '7'is aviewtaken' from the rwr side "of the 1 work. supporting arm showing the support and operating means for the front looper, also the support and operating means for the movable trimming blade, also showing the means for giving the needle avoiding movement to. the looper;

Fig. 7a. is a sectional view on the line l -I of Fig. '7;

Fig. 8 is a plan view of the presser foot associated with the covering stitching mechanism and also showing the chaining off mechanism;

Fig. 9 is a bottom plan view of the same;

Fig. 10 is a sectional view on the line 11-11 of Fig. 8;

Fig. 11 is a sectional view through the forward looper support and showing the connection between the same and the means which imparts the needle avoiding movement to the looper, and at the same time permits the looper to move up and down with the forward presser foot;

Fig. 12 is a top plan view of the front presser foot;

Fig. 13 is a bottom plan view of the presser foot;

Fig. 14 is a view showing in bottom plan the two presser feet, and showing in broken lines the path of travel of the edge portions as they are trimmed, stitched together and turned down for covering the same;

Fig. 14a. is a front view of the rear presser foot;

Fig. 15 is a plan view of the throat plate;

Fig. 16 is a sectional view through the rear presser foot and through the crosshead for reciprocating the loop supporting finger and showing some of the parts adjacent the same;

Fig. 1'7 is a view in side elevation showing the actuating parts for reciprocating the stitch finger or wire, and also the thread controls for the front needle;

Fig. 18 is a view showing diagrammatically and in transverse section the fabric sections after they have been joined by the through and through stitches and prior to the turning down of the edge portions;

Fig. 19 is a similar view showing the edge portions as covered by the twin needle covering stitches;

Fig. 20 is a view showing diagrammatically in side elevation the needle and looper at the time when the looper point is entering the needle thread loop;

Fig. 21 is a similar view showing the parts in plan view;

Fig. 22 is a view showing the looper and needle in side elevation at the time when the needle point is entering the thread triangle;

Fig. 23is a similar view in plan of the same;

and

-Fig. 24 is a diagrammatic view showing the operation of the thread controlling devices for the thread of the through and through stitching needle.

The invention as shown, is embodied in a sewing machine having a work supporting arm off from the end of which the fabric sections are fed as the edge portions thereof are trimmed, joined and covered. The fabric sections to be joined are fed beneath a presser foot with the edge portions thereof upturned. The presser foot holds the fabric sections on the work supporting arm and guides the same to the trimming devices which trim said upturned edge portions. The trimmed edge portions are then presented to a through and through stitching mechwith the presser foot as to move up and down I therewith under varying thicknesses of fabric passing beneath the presser foot. The presser foot has a groove extending all the way through the bottom surface thereof for directing the upturned edge portions, and the wall of the groove on the opposite side of the fabric sections entered by the needle serves as a support for the material being stitched. There is a rear presser foot which is mounted independent of the front presser foot, and this rear presser foot has a vanishing groove at the forward end thereof, one wall of which is in line with the work supporting wall of the front foot, and is shaped so as to turn down the edge portions after they have been joined by the through and through stitches flat against one of the fabric sections. Associated with the rear presser foot is a stitch forming mechanism which includes two needles mounted beneath a throat plate and movable up through the fabric sections at opposite sides of the turned down edge portions. Cooperating with these two needles is a thread carrying looper which connects the needle thread loops by looper thread loops which form the covering for the turned down edge portions. Associated with the rear presser foot is a loop supporting finger or wire over which the needle thread between successive needle punctures is laid by the feed of the fabric. This finger is withdrawn during each stitch formation and operates as a supporting means for the needle thread loops to insure stitch formation where there is no fabric section being stitched and permits chaining off between fabric sections. It is believed that the invention will be better understood by a more detail description of the illustrated embodiment thereof.

The machine to which the invention is applied is of the type shown in the Christensen and LeVesconte Patent No. 1,741,095, granted December 24, 1929. It will be apparent, however, that the improved stitch forming mechanism may be used in connection with other types of machines. Only a portion of the machine is shown, as the actuating shaft and the feeding mechanism are of the type disclosed in the patent referred to. Said machine includes a supporting standard or bracket I having an overhanging portion carrying a horizontal member 2 in which is located a main actuating shaft 3. Said shaft is operated by a belt wheel 4 with which is associated a hand wheel 5. Suspended from this upper horizontal member 2 is a work supporting arm 5 which is provided with the usual feeding mechanism including a feed dog I which is disposed so as to feed the material being stitched off from the end of the work supporting arm. This feed dog 1 is given the usual four motions so as to engage the fabric and impart thereto a feeding movement.

The material being stitched is supported on this work supporting arm 6. The work supporting arm carries a throat plate 8, which is shown Cal in plan view in Fig. 15. The throat plate is provided with feed slots 9 through which the feed dog operates for the feeding of the fabric. Said throat plate is secured to the work supporting arm by suitable screws, two of which are shown at l0, II) in Fig. l of the drawings. The throat plate extends beyond the end of the work supporting arm 6 and forms the fabric supporting means. Said throat plate has a raised portion centrally thereof as indicated at II in Figures 6 and 15. The portions at each side of this centrally raised portion ll incline downwardly away therefrom. This is for aiding in directing the fabric sections with the edge portions thereof upturned. The fabric portions to be stitched are placed on opposite sides of the work supporting arm and are brought together over the top thereof with their edge portions flat against each other, as clearly shown in Fig. 6 of the drawings, where the fabric sections are indicated at F and F, and the upturned portions are indicated at f and ,f. The portion. of the feed dog directly beneath this part of the throat plate having these inclined faces meeting at the center of the throat plate, are likewise inclined so as to engage the fabric both at the sides and adjacent the center of the throat plate.

The fabric sections are held on the throat plate by a presser foot it. The presser foot H has a central groove or recess l3 extending all the way through the presser foot from front to rear thereof, and opening at the under side of the foot. The walls of the presser foot at each side of this recess i3 are inclined outwardly and downwardly to conform to the shaping of the throat plate so that the fabric sections with the upturned edge portions guided through the groove or recess i3 will be firmly clamped either against the throat plateor the feed dog as the stitching takes place.

This presser foot 112 is provided with a supporting lug M which is clamped to a bracket portion I5 attached to the lower end of a presser bar it. A leaf spring i'i bears on a lug I8 attached to the upper end of this presser bar. This provides a yielding support for the presser foot so that it may rise and fall with the varying thicknesses of the fabric sections incident to cross seams or the like. The throat plate is rigid and the presser foot is a yielding member which not only rises and falls, as stated, but which can be lifted from the fabric sections when it is desired to remove the same from the machine or to insert new fabric sections for stitching.

The upturned fabric sections are first presented to a trimming mechanism which includes a stationary trimming blade I9 attached to the presser foot by a clamping plate 20, and a clamping bolt 2|. The recess or groove '13 in the presser foot extends all the way through the foot-as shown in Fig.1'13, in'theregion of the, trimming devices and in front thereof Coop- 1 erating with this'stat'ionary trimming blade I9 is a movable trimming blade 22.

251has asleeve 28 surrounding therear presser pending' armM secured byscrews 32, 32tola colla'r 33 which-is clamped to the presser bar:

21.11 011 spring 3l surrounding'the presser 'bar The movable 1 trimming blade 22 is clamped to a head 23 carried by "an arm 24"havin'g"a ribbedconnection toa-yoke member 25'. The yoke member 50."- will oscillate the needle.

2'! bears on the upper end of the yoke sleeve and yieldingly forces the movable cutting blade downwardly against the stationary shearing blade with which it cooperates. Said movable blade has the usual projecting finger or tongue which overlies the stationary blade and contacts therewith throughout the entire trimming operation. The presser foot is cut away to provide proper clearance. for the operation of the movable cutting blade. Mounted on the presser foot is a strip deflector 35 which is shown as moved to inoperative position in Fig. 1. This strip deflector normally extends across the slot in the presser foot and deflects the trimmed off edges away from the stitching mechanism. Inasmuch as the movable cutting blade is yieldingly pressed downward by the spring 3%, and the downwardmovement is limited by the stationary blade carried by the presser foot, the trimming mechanism will rise and fall with the presser foot. The raised portion on the throat plate terminates just at the rear of the trimming blades and the upturned edge portions after they are trimmed pass on through the groove in the presser foot and beneath the lug portion it which supports the presser foot.

The yoke member 25 carries a ball stud 36. A link 37! engages said ball stud on the yoke and also engages a ball stud 33 attached to an arm 39 carried by a sleeve M. This sleeve fill also carries an arm ii provided with a ball stud M to which is attached an eccentric strap t3 cooperating with an eccentric on the main actuating shaft. As the main actuating shaft rotates, it will, through this train of mechanism, impart oscillations to the yoke member and the movable trimming blade carried thereby.

sections will be guided along said wall, and the needle, which is a curved needle, oscillates, entering the fabric sections from the left, as viewed in Fig. 6. The needle 45 is clamped to an arm 46 by a suitable clamping means, and this arm is in turn clamped to a supporting sleeve mounted for oscillation on a bearing stud 41.

I Also attached to this sleeve is an arm 48 carrying a ball stud 49 to which a link 50 is attached.

The link 50 hasa' forked connection at its other end with an arm 5| rigidly attached toa shaft 52. ,The'shaft 52 carries an arm 53 provided] with a ball stud to which a link 54 is connected.

Thelink 54 is connected at its up'per endto a.

ball on the endo'ffia stud 55 which is adjustablehead and carries inside of the needle head a lever 59. i This lever '59has a forkede'nd. 60 carryi'n'g a pinto whichla link 6i isfconnectedzj The link 6| cooperates witha crankYGZ formeddn the a main actuatingtshaft'. the rnainshaft m-.. tates, it will oscillate the shaft 58, which-inturn oscillates theshaft 52, and this, through the link This bearing stud 41 on which the needle lever oscillates is carried by the bracket I 5 which supports the presser foot I2. The needle is, therefore, supported on the presser bar I6 and can move up and down with this presser foot. The needle is an eye-pointed needle of the usual type. After it passes through the fabric sections it throws out a needle loop at the side thereof which is entered by the thread carrying looper 63. Said thread carrying looper 63 is curved so as to lie in a plane parallel with the path or the plane in which the needle oscillates. The looper has a shank portion 64 extending at right angles to the plane of the looper, and this shank portion extends into the sleeve 65 carrying a collar 66 which is clamped to the end of a looper supporting shaft 61. This looper supporting shaft 61 is mounted in an extension I5 of the bracket I5. This extension is provided with projecting arms carrying spaced bearing sleeves I5 and I5 (see Fig. 7). On the opposite end of the looper supporting shaft 61 is an arm 68 carrying a ball stud 69. A link Ill cooperates with this ball stud and also engages a ball stud II carried by an arm I2 mounted on a shaft I2 supported in a bearing sleeve I3 carried by a bracket I4 which is bolted to the main standard or bracket I of the machine. The shaft 52 is also journaled in bearing sleeves I I and 14' formed in this bracket I4. Located between these bearings sleeves I4 and I I is an arm 15 which is attached to the shaft 52. There are two arms 15 extending out from the sleeve attached to the shaft 52, and a link I6 is connected to a pin between these two arms 15. This link I6 is also connected to the forked end ll of an arm attached to the shaft I2 This imparts an oscillation to the shaft I2 and in turn, through the link, will oscillate the looper shaft, imparting to the looper oscillating movements into and out of the needle thread loop. As shown in full lines in Fig. 4b, the arms I5, 15 are at an acute angle to each other and the looper is at the rear end of its stroke. As shown in Fig. 4a, the arms and the link have moved into alinement, and the looper is about to reach the end of its forward stroke. The arms and the link move slightly past dead center to the broken line position in Fig. 4b, and this is what gives a dwell to the looper at the forward end of its stroke.

The looper supporting shaft is moved endwise by means of an arm I8 freely mounted on the looper shaft and located between the collars 19 and which are fixed to the looper supporting shaft 61. This arm 18 engages a sleeve BI attached to a yoke 82. The yoke 82 is fixed to a rod 83. Said yoke is made in two parts and includes a sleeve I32 and also a sleeve 82*. These two sleeves are mounted on the rod 83 (see Fig. 7), and are connected by a bar 82 which is integral with sleeve 82* and bolted to the sleeve 92. This rod is mounted for reciprocation in a bearing 84 carried by a bracket 85 which is secured to the needle head by bolts 86 (see Fig. 1). Said bracket 85 has a depending forked arm 81 which straddles the bearing sleeve I 5 in which the looper shaft 61 is mounted for oscillation and endwise movement. The bearing sleeve has fiat sides, and is free to rise and fall in the fork of this arm 81. A strut 88 is attached to the forked arm 81 and is also connected to a pin 89 which is attached to the bracket I4.

Mounted on the yoke 82 is a ball stud 90. A

' ing shaft 3.

link 9| is connected to said ball stud, which in turn is connected to a ball stud 92 carried by an arm at the lower end of a vertical shaft mounted in bearing sleeves 93 and 94 carried by a bracket 95 which is bolted to the frame of the machine. The sleeve 40 is freely mounted on this shaft and oscillates thereon. There is an arm 96 attached to the upper end of the shaft which carries a ball stud 9I cooperating with an eccentric strap 98 which in turn cooperates with an eccentric on the main actuat- As the main actuating shaft ro tates, it will, through this link 9I, move the yoke 82 back and forth, and the yoke, through connection to the arm I8 will move the looper shaft endwise, thus giving to the looper its needle avoiding movement. The shaft 61 carrying the looper, can, however, move up and down with the presser foot, at which time the arm I8 will slide up or down in the sleeve 8|. This provides a means for positively oscillating the looper shaft, and for positively moving it endwise, and at the same time permitting the looper shaft to move up and down with the presser foot. The needle, in its oscillations is moved up and down with the presser foot, and this up and down movement of the looper shaft will maintain the proper cooperative position between the looper and the needle.

As has already been noted, the looper is mounted for oscillation in a vertical plane, the same as the needle. The center of oscillation of the looper is, as noted in Fig. 6, well to the right of the extreme inner position of the point of the needle, and also located close to the extended needle path, and as a consequence, the looper will cross the path of the needle substantially at right angles thereto. The operation of the needle and looper in the forming of a stitch will be possibly better understood from the diagrammatic views shown in Figures 20 to 23. In Figures 20 and 21, the needle has moved to the forward end of its stroke, and is retracted slightly, so as to throw out its needle thread loop. This is accomplished in the usual manner. The needle thread is indicated at n. The looper point is just about to enter this needle thread loop. The looper moves into a needle thread loop and to the end of its stroke, where it comes to a dwell. When the looper is at the forward end of its stroke, it is positioned so that the upper face thereof inclines upwardly away from the point of the looper. As a result, the needle thread loop, due to the tension on the loop, will slide up on the looper, which will raise the loop sufiiciently so that the needle on its next stroke can. pass beneath .the loop. The looper, while at a dwell, is given its needle avoiding movement, and this will carry the needle thread loop over the needle and across the needle to the opposite side thereof, while the looper thread itself, indicated at I, will be laid beneath the needle path and extend across the plane of oscillation of the needle. The needle will, therefore, enter the thread triangle formed by the needle thread loop, the looper thread and the body of the looper. It will be noted that the looper has very little lateral movement, and therefore, the entire stitching elements take up very little room lengthwise of the feed. enables the stitch forming mechanism to be placed close to the trimmers.

In Fig. 18, the fabric sections indicated at F and F, have the upturned edge portions 1 and j trimmed, and a line of stitching s has been This trimmer yoke oscillates on this sleeve Illl.

formed through these upturned edge portions by the needle 45 and the looper 53 which cooperates therewith. The next step in a flat seam formation is to turn the joined edge portions and 1' into a horizontal position flat against one of the fabric sections. In Fig. 19, these edge portions are shown turned down against the fabric section F. In order to cover these edge portions, a twin needle stitch forming mechanism is used including two needles and a looper cooperating with both needles. One of the needles forms needle loops s through the fabric section F,

while the other needle forms needle thread loops '3 through the fabric section F.

The looper thread 1' joins these needle thread loops s and s and the looper thread loops cover and tie down the edge portions, thus producing a flat seam, as shown in Fig. 19. i

The next feature in the machine is the means for turning the edge portion flat against the fabric section F. This is accomplished by the rear presser foot, which is shown in detail in Figures 8 to 10. The rear presser foot includes a body portion 99 which is attached to the presser bar 21. Said body portion has fabric engaging sections IIIIL-IIIII (see Fig. 9). These fabric engaging sections are spaced from each other and located between the same is a yielding foot section IN. This yielding foot section I III is carried by a supporting post IIIZ which slides freely in a sleeve bearing formed in the body portion 99. Said post carries a pin I03 which engages a slot in the body portion 99 and this prevents the foot portion from turning. A spring Int coiled about a stud I05 engages the foot portion MI and yieldingly presses the same downward. The pin Illii limits the downward movement of 'the foot portion. A screw IflIi threaded into the body portion bears against the end of the screw and serves as a means for varying the spring pressure of the foot against the fabric.

The foot portion IdI extends from a point directly in rear of the front presser foot I2, as shown in Figures 1 and 5, to the rear of the presser foot sections I00. The front portion of this foot IIII is broader and extends all the way across the sections Illll, IIW, while the rear portion is narrower and lies between said sections Mill, Hill.

The front ends of the sections I00, I00 are curved upwardly so that the foot will ride easily over a cross seam. This foot is carried by the presser bar 21, and a leaf spring located in the needle head bears on the sleeve 30 which is attached to the presser bar 21, and this yieldingly holds the foot pressed against the fabric.

The presser bar 2] has a reduced section at its lower end extending throughthe-sleeve 26 attached to the yoke operating the trimmer. The bracket I5 has' a sleeve IIII attached thereto which ektends up into the sleeve '26 so that the There is a shoulder in the presser bar 2'I which limits the downward movement of the presser bar 271 relative to the bracket I5. The rear presser foot is secured to the presser bar 21 by a screw I08. The foot is attached to the bar at a slight distance beneath the bracket I5. There is a washer I09 surrounding the bar and lying on the presser foot shank. This allows a limited movement of the rear foot up and down through the action of varying thicknesses of fabric beneath the same, which movement is independent of any up and down movements imparted to the front presser foot, trimmer and front stitching mechanism. The presser bar 21 is raised by a hand lever IW (see Fig. 2) which is connected through a train of mechanism with the bar within the needle head. When the presser foot is lifted, the washer I09 contacting with the bracket I5 will lift the bracket I5, and the front presser foot, so that by the single lever, both of the presser feet may be raised from engagement with the fabric for permitting the changing of the fabric. At the same time, the rear presser foot has this independent yielding movement.

The rear presser foot is provided with needle slots III, III, between which is a tongue IIZ overwhich the looper thread loop is laid. The looper thread loops joining the needle thread loops will pass off from the rear end of the stitch tongue. In the'under face of the fabric engaging portion MI is a groove or recess II3. This groove, as shown in Figures 9 and 14, has a substantially vertical wall II I which is in alinement with the wall in the front foot opposite the fabric supporting wall I3 The wall of the rear foot at the opposite side and upper side of the groove II3 is curved as indicated at IIS and vanishes into the bottom of the foot with the wall IM, and this Wallis so shaped as receive the upturned edge portions passing off from the vertical fabric supporting wall I3 and turns the same down into horizontal position just as they reach the needle slots II I, III, or the region of stitch formation of the cover seaming mechanism. The slot, as shown, terminates slightly in rear of these needle openings III, but insures that the edge portions are turned down flat before the region is reached where the stitches are drawn taut.

The throat plate 8 is provided with needle slots H6, H6, and with a feed slot III which extends between the needle slots. This operates on the fabric sections directly beneath the turned down portions, and insures a proper feeding of the same beneath the rear presser foot. The presser foot is substantially flat or horizontal in the region of the rear presser foot. The raised portion II terminates substantially at the rear end of the front presser foot so as to allow the seam to be fiat with the edge portions turned flat against one of the fabric sections when the covering stitching mechanism functions.

The covering stitching mechanism includes two needles H8 and IIQ. These needles are both clamped to a needle head IN. The needle head I20 has a groove in the side face thereof for the needle Md, and the needle is held in the groove by a clamping member I2I. There is a similar groove and clamping member on the opposite side of the needle head I20 for the needle IIIl. This needle head is carried by a lever member I22 which is mounted for oscillation on a stud I23. This stud is fixed to a rod I24 functioning as a needle bar. The lever I22 is pivoted at I25 to a stud carried by the throat plate 8. As the rod or needle bar IN reciprocates, it will cause the lever I22 to oscillate about the stud I25 and this will in turn cause the needles to move up through the fabric sections. -The needles pass up through the needle openings H6, H6 in the throat plate, then through the fabric sections, and then through the needle slots III in the rear presser foot. The needles are curved and are eye-pointed, and each is provided with a thread. It will be noted that the needles pass through the fabric sections in substantially a vertical direction, but each needle moves in a path curving toward the horizontal within the work arm so that the needles can be mounted in a relatively small work arm and have the necessary stroke given thereto for the penetrating of the fabric and the stitch formation. The rod or needle bar I24 is rigidly connected to a link I26 which in turn is pivoted at I21 to a rod I28 reciprocating in a slot I29. The rod I28 is connected by a link I30 to a rock lever I3I. Said rock lever is pivoted at I32 to the frame, and carries a ball stud I33 which in turn is connected to a link I34 engaging at its upper end a ball stud I35 carried by a crank on the main actuating shaft 3. The rod I28 reciprocates in a right line in a sleeve I29 and imparts an endwise movement to the link I26 which in turn reciprocates the rod or needle bar I24 and causes the needles to oscillate in the manner described above. The link I26 is provided with right and left-hand threads so that it may be lengthened or shortened for varying the oscillating position of the needles.

Cooperating with the needles above the presser foot is a looper 136. The looper is a thread carrying looper and will first pass into the needle thread loop formed by the needle H8 and then into the needle thread loop formed by the needle II9. This looper is oscillated back and forth in a vertical plane, substantially at right angles to the line of feed. The looper is also given a needle avoiding movement so that after the looper has entered the needle thread loops, it moves laterally and positions the thread triangles for the respective needles to enter. This stitch forming mechanism is the well-known twin needle stitch forming mechanism, and further description of the stitch formation is not thought necessary.

The looper I36 oscillates in a vertical plane and is provided with a shank I31 which extends at right angles to said plane of oscillation. The shank I31 is clamped in the end of an arm I38 carried by a sleeve I39. This sleeve I39 is mounted for oscillation and endwise movement on a supporting rod I40 carried by a depending member I formed integral with the bracket 85. Said sleeve I39 has attached thereto a pro- Jecting arm I42 carrying a ball stud to which a link I43 is connected. The link I43 at its other end is attached to a ball stud I44 mounted for adjustment in a slot I45 carried by an arm I46 which is fixed to the shaft 58. As the shaft 58 oscillates, it will, through the link l43, impart oscillations to the sleeve I39 and to the looper I36. This link I43 is connected to a ball stud at each end and this permits the sleeve I39 to move endwise of the rod I40 as well as to oscillate on said rod. Fixed to the end of the rod 83 is an arm I41. This arm is provided with a collar I48 (see Fig. 1) which engages the extension I 39 of the sleeve I39 (see Fig. 2). On the end of this extension is clamped a collar I49. The arm I46 moves laterally with the endwise movements of the rod 83 and this will shift the sleeve I39 endwise on the rod I40, at the same time permitting the sleeve to oscillate. The rod 83, as has been described above, is utilized for giving lateral movements to the looper which cooperates with the front needle. It likewise gives the lateral movements to this looper cooperating with the rear needles. The rear looper has no up and down movement relative to the rear presser foot,

but moves in a fixed path relative to the needle head.

In order to provide a means for forming stitches when there is no fabric in the machine, a stitch finger or wire I50 has been provided (see Figures 8 and 9). This finger is mounted for reciprocation in a passageway formed in the fabric engaging member IOI of the rear presser foot. It passes across the slots alongside of the stitch tongue H2 and through the stitch finger. The stitch finger I50 moves in a path at right angles to the line of feed. It is in this forward position as shown in Fig. 9 when the needles penetrate the fabric, and after the looper has entered the needle thread loops, so as to hold the same, then the stitch finger or wire I50 is quickly retracted. At this time the needles are withdrawn from the fabric and the feed takes place. As

-the looper retracts and the needles move up to penetrate the fabric, the stitch finger is quickly projected forward and remains across the slots during the rising of the needles. If there is no fabric in the machine, then the needle thread between consecutive stitches, as the needles rise, will be laid over this finger or wire I50. It takes the place of the fabric and supports the needle thread loops. Otherwise, there would be no means for anchoring the needle thread loops and no loop would beformed which the looper could enter. It is retracted, as noted above, so as to permit the feed after the loop formation has been effected. The purpose of this finger or wire I50 is solely to insure stitch formations when there is no fabric in the machine, and th: 3 permits the chaining between fabric sections. This chaining means in connection with a twin needle stitch forming mechanism may be used in other types of machines, and with any twin needle stitching mechanism, and is not limited in its use to the particular type of machine shown, or in combination with the particular features described.

The stitch finger or wire I50 is fixed to a crosshead I5I mounted for reciprocation on two rods I52 and I53 which are rigidly carried by the yielding fabric engaging portion IOI of the rear presser foot. These rods, of course, move up and down with the yielding section of the presser foot, and also with the presser foot as a whole. The crosshead I5I has an upstanding rib I54 which engages between spaced ribs on a member I55. This member I55 is clamped to the end of a rod I56 by clamping screws I51. Extending laterally from the body portion of the presser foot is an arm I58 which is in the form of a sleeve, and in this sleeve the rod I56 is mounted for endwise reciprocation. There is a slot I59 in one side of the arm which leads to the inner recess thereof, and a stud I60 is threaded into the rod I56 and projects out through the slot I58. A link I6I is connected to the stud and at its outer end is pivoted to an arm I62 attached to a short shaft I63. This shaft carries an arm I64 which is pivoted at its upper end to a link I65, and the link I65 in turn is pivoted to a stud I66 carried by a sleeve I61 which slides freely on the presser bar I6. The sleeve I61 is provided with a lug I68 to which a short link I69 is connected. The upper end of this link I69 is in turn attached to an arm I10 fixed to the shaft 58. As the shaft 58 oscillates, it will move the sleeve I61 up and down on the presser bar, and this will oscillate the' arm I62 and impart endwise movement to the crosshead carrying the stitch finger or wire I 50. It will be noted from 7 it is quickly retracted to permit the thread loops scribed.

the thread eye lit.

laid over the same during chaining to be released and the feed of the same to take place.

The thread controlling mechanism has been provided for the needle 65. This thread controlling mechanism includes a thread guide. l' which is attached to the frame of the machine so that it may be adjusted vertically. Mounted on the shaft M3 for movement with the arm Nil is a wire H2 having a thread guiding hook H3. The needle thread indicated at n passes through the thread guide ill and the thread guiding hook H3. It also passes through an eye I'll on a bracket i115 attached to the arm llll. As shown diagrammatically in Fig. 24, the bracket H5 is shown in full lines at its extreme lowest position and in broken lines at its extreme upper position. It will be noted that the wire llZ moves toward and from the thread guide Hi. It moves toward the thread guide when the bracket H5 is moving to its extreme upper position, so that while said thread eye formed in the bracket H5 is taking up on the thread, the thread guiding hook H3 is giving up a certain amount of thread, and this will reduce, to a certain extent, the amount of thread that is taken up. The purpose is to utilize this arm Hill which has a relatively long stroke for taking up an amount of thread which is slightly less than would normally be taken up by the movement of These parts are so timed that when this thread eye ll l reaches the upper end of its stroke, the needle is retracted from the fabric, the feed is taking place, and the stitch is being set.

It is thoughtthat the operation of the machine will, be obvious from the description which has been given in detail of the mechanisms which cooperate to produce the flat seam de- The edge portions are upturned and trimmed and then passed to the stitching mechanism which joins the edge portions. This stitching mechanism, which includes a needle and looper, is so mounted that it can move up and down with the presser foot with which it is associated. Likewise, the trimming devices which trim the edges move up and down with the presser foot so that this -line of stitching which joins the fabric sections will always be placed in the fabric sections a given distance from the trimmed edges, regardless of cross scams or varying thicknesses in the fabric, which mayraise or lower the position of the presser foot. After the edges are joined, they pass beneath the second presser foot which has a receiving groove or recess shaped so as to turn down the joined edges flat against one of the fabric sections. While passing beneath this foot, two needles pass up through the fabric sections beneath the work support, and the thread carrying looper above the fabric sections cooperates with the needles for interlocking the needle thread loops in the looper thread loop which covers the turned down edge portions. In order that this stitching mechanism may function to chain off between articles, a thread finger is provided which moves through the presser foot and the stitch finger and is timed so that the needle threads are laid across this finger by the feed and support the thread so that loops may be formed for the looper to enter. After the thread loops are enchained, then the stitch finger is retracted so as to permit said enchained thread loops to be fed.

It is obvious that many changes may be made in the stitch forming devices and. the parts associated therewith, and also in the specific structures used in connection with each of the various mechanisms described without departing from the spirit of the invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Letters- Patent, is-

1. A sewing machine comprising a work support, a feeding mechanism, a stitch forming mechanism for joining the edge portions of fabric sections, means for turning down both of the joined edge portions fiat against one of the fabric sections and a second stitch forming mechanism for covering and securing the turned down edge portions to the fabric sections by covering stitches passed through the respective fabric sections at each side of the turned down edge portions and adjacent the same.

2. A sewing machine comprising a work support, a feeding mechanism, a stitch forming mechanism for joining the edge portions of fabric sections, means for turning down both of the joined edge portions fiat against one of the fabric sections, and a two-needle stitch forming mechanism for passing needle thread loops through the respective fabric sections at each side of the turned down edge portions and adjacent the same and for joining said needle thread loops with a thread for covering said turned down edge portions.

3. A sewing machine comprising a work support, a feeding mechanism, a stitch forming mechanism for joining the edge portions of fabric sections, means for turning down both of the joined edge portions flat against one of the fabric sections, and a two-needle stitch forming mechanism for passing needle thread loops upwardly through the respective fabric sections at each side of the turned down portions and adjacent the same and for locking said needle thread loops with the looper thread which covers and secures the turned down edge portions to the fabric sections.

4. A sewing machine comprising a work support, a feeding mechanism, stitch forming mechanism for joining ,the edge portions of fabric sections, means for trimming the edge portions of fabric sections and directing the same to said stitch forming mechanism, means for turning down both of the joined edge portions fiat against one of the fabric sections, and a second stitch forming mechanism for covering and securing the turned down edge portions to the fabric sections by covering stitches passed through the respective fabric sections at each side of the turned down edge portions and adjacent the same. a

5. A sewing machine comprising a work support, a feeding mechanism, stitch forming mechanism for joining the edge portions of fabric sections, means for trimming the edge portions of fabric sections and directing the same to said stitch forming mechanism, means for turning down both of the joined edge portions flat against one of the fabric sections, and

a two-needle stitch forming mechanism for passing needle thread loops through the respective fabric sections at each side of the turned down edge portions and adjacent the same and joining the same with a covering thread for covering and securing the turned down edge portions to the fabric sections.

6. A sewing machine comprising a work support, a feeding mechanism, stitch forming mechanism for joining the edge portions of fabric sections, means for trimming the edge portions of fabric sections and directing the same to said stitch forming mechanism, means for turning down both of the joined edge portions flat against one of the fabric sections, and a two-needle stitch forming mechanism for passing needle thread loops upwardly through the respective fabric sections at each side of the turned down edge portions and adjacent the same and for locking said needle thread loops by looper thread loops which cover and secure the edge portions to the fabric sections.

'7. A sewing machine comprising a work support, a feeding mechanism, a presser foot cooperating with said feeding mechanism for directing the upturned edge portions of fabric sections, a stitch forming mechanism for joining the upturned edge portions including a needle and a looper, a second presser foot cooperating with said feeding mechanism and having means for turning down both of the joined edge portions fiat against one of the fabric sections, and a second stitch forming mechanism for covering and securing the turned down edge portions by covering stitches passed through the respective fabric sections at each side of the turned down edge portions and adjacent the same.

8. A sewing machine comprising a. work support, a feeding mechanism, a presser foot cooperating with said feeding mechanism for directing the upturned edge portions of fabric sections, a stitch forming mechanism for joining the upturned edge portions including a needle and a looper, a second presser foot cooperating with said feeding mechanism and having means for turning down both of the joined edge portions flat against one of the fabric sections, and a twoneedle stitch forming mechanism including needles mounted beneath the work support for carrying needle thread loops up through the respective fabric sections at each side of the turned down edge portions and adjacent the same, and a looper mounted above the work support and cooperating with said needles for covering and securing the turned down edge portions to the fabric sections.

9. A sewing machine comprising a work support, a feeding mechanism, a presser foot cooperating with said feeding mechanism for directing the upturned edge portions of fabric sections, a stitch forming mechanism for joining the upturned edge portions including a needle and a looper, a second presser foot cooperating with said feeding mechanism and having means for turning down both of the joined edge portions fiat against one of the fabric sections, and a two-needle stitch forming mechanism including needles mounted beneath the work support and operating to pass needle thread loops up through the fabric sections at each side of the turned. down edge portions, a thread carrying looper mounted above the work support and cooperating with both needles for covering and securing the turned down edge portions to the fabric sections, and means cooperating with said twoneedle stitch forming mechanism for supporting the needle threads so that enchained thread loops may be formed thereby when there is no fabric to be stitched.

10. A sewing machine comprising a work support, a feeding mechanism, a presser foot cooperating with said feeding mechanism and having a slot for directing the upturned edge portions of fabric sections, a throat plate having inclined meeting surfaces disposed relative to the slot in the presser foot so as to direct the edge portions of the fabric sections through said slot with said edge portions contacting with one of the walls of said slot, a stitch forming mechanism including a needle, operating to penetrate the fabric sections while in engagement with the wall of the slot, a looper cooperating with said needle, means for turning down both of the joined edge portions flat against one of the fabric sections, and a second stitch forming mechanism disposed relative to the turned down edge portions so as to form covering stitches passing through the respective fabric sections adjacent the turned down edge portions and overlying the same.

11. A sewing machine comprising a work support, a feeding mechanism, a presser foot cooperating with said feeding mechanism and having a slot for directing the upturned edge portions of fabric sections, a throat plate having inclined meeting surfaces disposed relative to the slot in the presser foot so as to direct the edge portions of the fabric sections through said slot with said edge portions contacting with one of the walls of said slot, a stitch forming mechanism including a needle, operating to penetrate the fabric sections while in engagement with the wall of the slot, a looper cooperating with said needle, a trimming mechanism operating in advance of the needle for trimming the upturned edge portions, means for turning down both of the joined edge portions flat against one of the fabric sections, and a. second stitch forming mechanism disposed relative to the turned down edge portions so as to form covering stitches passing through the respective fabric sections adjacent the turned down edge portions and overlying the same.

12. A sewing machine comprising a work support, a feeding mechanism, a presser foot cooperating with said feeding mechanism and having a slot for directing the upturned edge portions of fabric sections, a throat plate having inclined meeting surfaces disposed relative to the slot in the presser foot so as to direct the edge portions of the fabric sections through said slot with said edge portions contacting with one of the walls of said slot, a stitch forming mechanism including a needle operating to penetrate the fabric sections while in engagement with the wall of the slot, a looper cooperating with said needle, and means for supporting said presser foot, needle and looper whereby said presser foot, needle and looper may rise and fall with varying thicknesses of material and the stitch forming devices operate in a predetermined position relative to the presser foot for all positions thereof.

13. A sewing machine comprising a work support, a feeding mechanism, a presser foot cooperating with said feeding mechanism and having a slot for directing the upturned edge portions of fabric sections, a throat plate having inclined meeting surfaces disposed relative to the slot in the presser foot so as to direct the edge portions of the fabric sections through said slot with said edge portions contacting with one of the walls of said slot, a stitch forming mechanism including a needle, operating to penetrate the fabric sections while in engagement with the wall of the slot, a looper cooperating with said needle, a trimming mechanism operating in advance of the needle for trimming the upturned edge portions, and means for supporting the trimming mechanism, the stitch forming mechanism and the presser foot whereby the presser foot, trimming mechanism and stitch forming mechannism may rise and fall with varying thicknesses of the fabric and the stitch forming mechanism and trimming mechanism will operate in a predetermined position relative to the presser foot for all positions thereof.

14. A sewing machine comprising a work supporting arm, a feeding mechanism including a feed dog for feeding the material off from the end of the work supporting arm, a presser foot cooperating with said feeding mechanism and work support for directing the upturned edge portions of fabric sections, a stitch forming mechanism including a needle movable through the fabric sections in substantially a horizontal line, a thread carrying looper cooperating with said needle, said presser foot being mounted so as to move up and down with varying thicknesses of fabric, and said needle and looper being mounted so as to move with the presser foot and operate on said fabric sections in a predetermined position relative thereto for all positions of the presser foot, means for turning down both of the joined edge portions flat against one of the fabric sections, and a second stitch forming mechanism disposed relative to the turned down edge portions so as to form covering stitches passing through the respective fabric sections adjacent the turned down edge portions and overlying the same.

15. A sewing machine comprising a work supporting arm, a feeding mechanism for feeding fabric sections off from the end of said am, a presser foot having a slot for directing upturned edge portions of fabric sections, a stitch forming mechanism including a curved needle mounted for oscillation about an axis located directly above the edge portions of the fabric sections, a thread carrying looper cooperating with said needle and mounted for oscillation about an axis parallel with the axis of the needle above the needle path and so that the looper crosses the path of the needle substantially at right angles when entering the needle thread loop, means for oscillating said looper, and means for giving to said looper a lateral needle avoiding movement.

16. A'sewing machine comprising a work supporting arm, a feeding mechanism for feeding fabric sections off from the end of said am, a presser foot having a slot for directing upturned edge portions of fabric sections, a stitch forming mechanism including a curved needle mounted for oscillation about an axis located directly above the edge portions of the fabric sections, a curved thread carrying looper mounted for oscillation about an axis parallel with the axis of the needle and located above and adjacent the needle path whereby said looper when entering the needle thread loop crosses the path of the needle substantially at right angles, and whereby the curvature of the looper will cause the needle thread loop to slide upwardly thereon during the formation of the thread triangle so that the needle may pass beneath the needle thread loop as it enters said triangle, means for oscillating said looper, and means for giving to said looper a lateral needle avoiding movement.

17. A sewing machine comprising a work supporting arm, a feeding mechanism for feeding 5 fabric sections 011 from the end of said arm, a presser foot having a slot for directing upturned edge portions of fabric sections, a stitch forming mechanism including a curved needle mounted for oscillation about an axis located di- 10 rectly above the edge portions of the fabric sections, a curved thread carrying looper mounted for oscillation about an axisparallel with the axis of the needle and located above and adjacent the needle path whereby said looper when 16 entering the needle thread loop moves from a point above to a point below the path of the needle and substantially at right angles and whereby the curvature of the looper will cause the needle thread loop to slide upwardly there- 20 on during the formation of the thread triangle so that the needle may pass beneath the needle thread loop as it enters said triangle, and means for oscillating said looper and giving thereto a dwell at the forward end of its stroke.

18. A sewing machine comprising a work supporting arm, a feeding mechanism for feeding fabric sections off from the end of said arm, a presser foot having a slot for directing upturned edge portions of fabric sections, a stitch forming mechanism including a curved needle mounted for oscillation about an axis located directly above the edge portions of the fabric sections, a thread carrying looper cooperating with said needle and mounted for oscillation about an axis above the needle path and so that the looper crosses the path of the needle substantially at right angles when entering the needle thread loop, means for oscillating said looper, means for giving to said looper a needle avoiding movement, means for supporting said presser foot whereby it may move up and down with the fabric, said needle and said looper being carried by the supporting means. for the presser foot so as to move up and down therewith, means for 5 turning down both of the Joined edge portions fiat against one of the fabric sections, and a second stitch forming mechanism disposed relative to the turned down edge portions so as to form covering stitches passing through the respective 5 fabric sections adjacent the turned down edge portions and overlying the same.

' 19. A sewing machine including in combination a work support, a feeding mechanism, a presser foot for directing the upturned edge portions of 5 fabric sections, stitch forming mechanism associated therewith for joining said edge portions including a needle movable in substantially a horizontal direction through the fabric sections,- a thread carrying looper cooperating therewith, 69 means for oscillating the needle, means for oscillating the looper, a second stitch forming mechanism in rear of the first-named stitch forming mechanism and operating to cover the joined edges of the fabric sections, said second stitch forming mechanism including two needles mounted beneath the work support and movable upwardly through the fabric sections, a thread carrying looper cooperating with said needles, means for oscillating said thread carrying 70 looper, and common means for giving to the looper associated with the first stitch forming mechanism and the looper associated with the second stitch forming mechanism a lateral needle avoiding movement. 7 5

30. A sewing machine including in combination

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