US1950336A - Sewing machine - Google Patents

Description

March 6, 1934. ZEIER 1,950,336

SEWING MACHINE Filed April 10,1931 l2 Sheets-Sheet l March 6, 1934. ZEIER 1,959,336

SEWING MACHINE Filed April 10, 1931 12 Sheets-Sheet 2 March 6, 1934. F, F. ZEIER 1,95,336

SEWING MACHINE Filed April 10, 1931 12 Sheets-Sheet 3 F. F. ZEIER SEWING MACHINE March 6, 1934.

Filed April 10, 1931 1,2 Sheets-Sheet 4 F. F. ZEIER SEWING MACHINE March 6, 1934.

Filed April 10, 1931 12 Sheets-Sheet 5 n W I 17; Q fi Cuba/wags 12 Sheets-Sheet 6 w wN dam/ 1 s F. F. ZEIER SEWING MACHINE Filed April 10, 1931 March 6, 1934.

March 6, F. ZEIER SEWING MACHINE Filed April 10, 1931 12 Sheets-Sheet 7 I I 2 a9 a a;

T M a March 6, 1934. F. F. ZEIER 1,950,336

SEWING MACHINE Filed April 10, 1931 12 Sheets-Sheet 8 fir J? W g g March 6, 1934. F. F. ZEIER I 1,950,336

SEWING MACHINE Filed April 10, 1931 12 Sheets-Sheet 9 March 6, 1934. F. F. ZEIER 1,950,336

SEWING MACHINE Filed April 10, 1931 '12 Sheets-Sheet 10 F. F. ZEIER SEWING MACHINE March 6, 1934..

Filed April 10, 1931 1 Sheets-Sheet 11 F. F. Z EIER SEWING MACHINE March 6, I934.

. Filed April 10, 1931 12 Sheets-Sheet 12 Patented Mar. 6, 1934 amass sawmc Frederick F. Zeier, Chicago, 111., minim-u Union Special Machine Company, Chicago, 111., a corporation of Illinois Application April 10, 1931, Serial No. 529,241

30Claims.

The invention relates to new and useful improvements in sewing machines, and more particularly to a sewing machine having an upper member carrying a main actuating shaft and having a needle head at one end thereof and a suspended work arm at the other, in which work arm is mounted the looper mechanism and feeding mechanism for stitching and for feeding the material on the end of the work arm as it is stitched.

The preferred type of machine in which the invention is embodied is that shown in Patent No. 1,741,095, granted Norman V. Christensen and Harold J. Le Vesconte, December 24, 1929.

An object of the invention is to provide a machine of the above type wifh a looper which is moved longitudinally of the work arm for its loop taking movement and laterally of the work arm for its needle avoiding movement, by an oscillating endwise moving lever in said arm, and wherein said lever is given its movements from an eccentric member on the actuating shaft directly connected to a lever in the depending member carrying the work arm.

A further object of the invention is to provide a machine of the above type wherein the lever in the work arm is mounted for reciprocation and also for oscillation on a device located intermediate the ends thereof, and which is constructed so that it can be shifted for varying the extent of endwise and lateral movement imparted to the looper.

A further object of the invention is to provide a machine of the above type wherein the lever in the depending member is mounted for endwise and oscillating movements on a device which may be shifted laterally of the lever for changing the working position or path of movement of the looper.

A still further object of the invention is'to provide a machine of the above type wherein the looper carrier is mounted on thelooper supporting lever which imparts movements thereto so that it may be shifted from one set position to another in a direction lengthwise of the lever.

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

In the drawings- Figure 1 is a view partly in plan and partly in sec'ion of a machine embodying the improvements, the cover plates being removed to show the mechanism beneath the same in the upper horizontal member;

Fig. 2 isa view partly in side elevation and partly in section of the same, showing the operating connection to the main actuating shaft 10 both the looper and the feed;

Fig. 3 is a view partly in end elevation and partly in section, showing more particularly the means for operating the needle bar from the so main actuating shaft;

Fig. 4 is a vertical longitudinal sectional view through the work arm, showing the operating parts therein, and showing in part, the devices for transmitting the movements of the parts in the depending member to the parts in the work arm:

Fig. 5 is a view partly in plan and partly in section of the parts shown in Fig. 4, and with the feed bars broken away to show the looper operating lever and the looper carrier beneath the same;

Fig. 5' is a vertical sectional view through the work arm, and showing the mountings for the inner ends of the feed bars and the devices contained in said work arm for actuating said feed bars;

Fig. 5 is a vertical sectional view through the work arm, showing the feed device which moves the feed bars endwise and also showing the manner of supporting the inner end of the looper lever, other parts being omitted from this view for the sake of cleamess;

Fig. 6 is a view similar to Fig. 5, but showing only the looper operating mechanism, the loopers and the spreader which cooperates therewith, these parts being shown in plan;

Fig. '7 is a sectional view on the line 77 of Fig. 4, the feed and the spreader'being omitted;

Fig. 8 is a sectional view on the line 8-8 of Fig. 4;

Fig. 9 is a view showing the fulcrum support for the lever in the work arm, the parts being sep arated to more clearly show their structure;

Fig. 9 is a detail sectional view showing the thread guide mounting for the looper threads which is carried by the work arm;

Fig. 9 is a similar detail view showing the thread guide in side elevation;

Fig. 10 is a view showing the lever in the depending arm operated by an eccentric member on the actuating shaft for imparting movements .tothe looper;

Fig. 11 is a sectional view showing the support for the lever in Fig. 10 in side elevation;

Fig. 12 is a view showing the looper carrier and the means for shifting the looper carrier endwise of the supporting lever'therefor;

Fig. 13 is a view similar to Fig. 12, showing the looper as shifted away from the needle to its extreme e ting to the left, as viewed in this figure;

the arm of the operator.

Fig. 14 is a similar view showing the looper shifted to an intermediate position between those shown in Figures 12 and 13;

Fig. 15 is a diagrammatic view showing the looper operating mechanism and the result of the shifting of the fulcrum for the lever in the depending member;

Fig. 16 shows diagrammatically the effect upon the path of movement of the looper by the shifting of the fulcrum for the lever in the work arm;

Fig. 17 is a sectional view through the spreader and showing the supporting means for carrying the looper threads;

Fig. 18 is a sectional view showing more or less diagrammatically the stitching elements and one resulting seam therefrom;

Fig. 19 is a plan view showing the loopers and the spreader in operation for spreading and positioning the looper thread loops;

Fig. 20 is a plan view of the same parts showing the needles entering the looper thread loops;

Fig. 21 is a similar view showing the looper thread loops when dropped by the spreader and while still retained by the needles;

Fig. 22 is a view showing more or less diagrammatically the arrangement of the fabric sections 'and the threads in the finished seam produced on the illustrated embodiment of stitch forming mechanism;

Fig. 23 is a view similar to Fig. 19, but showing a modified form of spreader which results in a different stitch formation;

Fig. 24 is a view similar to Fig. 22, but showing the spreader as positioning the looper thread loops for the entrance of the needles; and

Fig. 25 is a view similar to Fig. 23, but showing the loops released from the spreader but still on the needle.

The sewing machine embodying the invention is of the type disclosed in the Christensen & Le Vesconte patent above referred to, and includes a standard which curves upwardly and outwardly to form an overhanging bracket to which is attached the upper horizontal member of the sewing machine frame proper. Extending lengthwise of this upper horizontal member is the main actuating shaft. At one end of said horizontal member is the needle head, and at the other end thereof, a depending member, which is spaced from the bracket to provide a clearance space for At the lower end of this depending member is a work arm. The actuating shaft extends over the depending member so that all of the parts in the work arm are actuated from this shaft bydirect connections with members extending downwardly through the depending member.

The present invention has particularly to do with the looper operating mechanism, and includes a lever mounted in the work arm so that it may be moved endwise for giving the loop taking and leaving movements to the loopers, and also laterally for giving the needle avoiding movements to the loopers. This lever carrying the loopers is actuated by a single eccentric member on the actuating shaft which is directly connected to a lever having an endwise and oscillating movement located in the depending member. This lever engages a fulcrum block located inter- -mediate the ends thereof, and the lower end of The fulcrum block for the lever in the work arm is made so that it may be shifted, and thus the character of the path of movement. of the loopers varied. This shifting of the fulcrum block is in a direction endwise of the lever. The fulcrum block for the lever in the depending member is capable of being shifted laterally to different set positions, and this varies the working position or path of travel of the loopers. The looper carrier on which the loopers are mounted is capable of being shifted to differentset positions on the lever which operates the same, so that when the fulcrum blocks are shifted, the loopers may be placed so as to obtain proper timing with the needles.

The invention will be better understood by a detail description of the illustrated embodiment of the invention. The sewingmachine includes a supporting standard or base 1 which curves upwardly and outwardly forming a bracket 2 which supports the upper horizontal member 3 of the main sewing machine frame. Extending lengthwise of this upper horizontal member is a main actuating shaft 4. This main actuating shaft is provided with a belt wheel 5 by which it is rotated. It is also provided with a hand wheel 6. At the left-hand end of the upper horizontal member as viewed in Fig. 1, is a needle head 7 in which a needle bar reciprocates, carrying, in the present instance, three needles 9, 10 and 11. The needle bar is reciprocated bymeans of a lever 12 which is carried by a fulcrum shaft 13 mounted in the needle head. A link 14 connects the lever to a lug 15 carried by a collar attached to the needle bar. The rear end of the lever 12 is connected to a link 16 which cooperates with a crank 17 formed in the main actuating shaft 4. The needle actuating mechanism per se forms no part of the present invention and further description thereof is not thought necessary.

At the other end of the upper horizontal member 3 is a depending member 18. This depending member 18 is located directly beneath the right-hand end of the upper horizontal member, as viewed in Figures 1 and 2, and the actuating shaft 4 extends within the depending member. At the lower end of this depending member is a suspended Work arm 19. The work arm is attached to the lower end of the depending member by suitable bolts 20. This work arm, toward its free end, is substantially rectangular in shape, and is relatively small, so that the machine is particularly adapted for stitching tubular parts of garments. The material is held on the work support by a presser foot 21, and is fed along the work support by a feeding mechanism which includes a main feed dog 22 and an auxiliary feed dog 23 (see Fig. 4 of the drawings). These feed dogs may be actuated so as to have a differential feeding movement, and thus it is that the machine is equipped for stitching elastic materials, such as knit goods. The presser foot is preferably constructed so that the fabric sections being stitched may have their edges lapped and directed to the stitching mechanism, when three needles are used, so that the center needle passes through the lapped sections as indicated diagrammatically in Fig. 22. When three needles are used in the manner stated, three loopers are provided, which are indicated at 24, 25 and 26.

at 28 and the other at 28* in Fig. 18 ofthe draw.- ings. These thread laying devices form the cover thread into loops which are stitched down by the needle threads so as to cover the fabric sections on the upper face thereof. In Fig. 18 of the drawings, the needle 10 is illustrated which forms the center-line of stitching, and the looper 25 which cooperates therewith. The needle thread of this needle is indicated at n. The cover thread is indicated at c. The looper thread for the looper 25 is indicated at l'. The two fabric sections are indicated at F and F. They are shown as overlapping and as penetrated by this needle. The operation of the looper mechanism will be described more in full later.

When the fabric sections are lapped and acovering seam produced, the machine is equippedwith a trimming mechanism which trims the upturned edges before they are lapped. Inasmuch as the present invention is directed particularly to the looper operating mechanism for this type of machine, it is not thought necessary to describe in detail herein the trimmer operating mechanism, presser foot, and the cover thread laying mechanism.

The feed' dog 22 is carried by a feed bar 29 which extends lengthwise of the work arm. The feed dog 23 is carried by a feed bar 30 which likewise extends lengthwise of the work arm. The feed bars are both mounted on a fulcrum pin 31. There is an opening 32 in each bar which is closed at the lower side thereof by a plate 33 secured to the feed bars in any suitable way. There is a plate for each bar. Mounted on this fulcrum pin 31 are bearing blocks 34 for the feed bar 29 and bearing blocks 35 for the feed bar 30. The feed levers slide on these bearing blocks. The fulcrum pin 31 carries an eccentric portion, and by turning this fulcrum pin, the bearing blocks which form the fulcrum support for the feed bars may be raised and lowered, and thus the elevation of the feed dogs changed. The feed bars slide between side bearing plates 36 and 37. The fulcrum pin 31 passes through these plates. These plates have another function which will be described later.

The feed bar 29 at its irmer end is pivoted to a link 38 which in turn is connected to a pivot pin 39. This pivot pin 39 is carried by an arm 40. The feed bar 30 is pivotally connected to a link 41 which is connected to the same pivot pin 39. The arm is carried by a sleeve 42 which is mounted for oscillation on a shaft 43. An eccentric strap 44 cooperates with a ball 45 on the pivot pin 39 and with an eccentric 46 on the main actuating shaft 4. As the main shaft rotates, this eccentric strap 44 will raise and lower the arm 40, which in turn will raise and lower the inner ends of the feed bars, and thus the feed dogs are raised and lowered thereby. The feed bar 29 is moved back and forth by a link 47 which is pivoted at,

48 to the feed bar, and the inner end of this link is connected to an arm 49 formed as an integral part of a sleeve 50 which in turn is mounted for oscillation on a shaft 51.

The feed bar 30 is moved back and forth by feed bar, and at its inner end carries a stud 54 engaging an arm 55. The arm is slotted at 56 to receive this stud 54, and the stud may be raised and lowered in the slot for varying the throw imparted to this feed bar 30. This arm is formed as an integral part of the sleeve 50 and oscillates the same. The arm 57 is formed integral with the sleeve 50 and is slotted at 58. A stud 59 is mounted therein'for adjustment. A link 60 is pivoted to this stud, and is pivoted at its upper end to a-stud 61 carried by a lever 62 which is mounted for oscillation on the shaft 43. This lever 62 carries a ball stud 63 to which an. eccentric rod 64 is attached. This eccentric strap cooperates with an eccentric 65 on the main shaft 4. As the main shaft rotates, the lever 62 will be oscillated which will in turn impart oscillations to the arm 57. This oscillates the sleeve 50 and thus imparts endwise movements to the feed bar 30. Means is provided for regulating the stroke of both feed dogs when the stud 59 is shifted, and for regulating the stroke of the auxiliary feed bar independently of the stroke of the main feed bar when the stud 54 is shifted. This feeding mechanism which has .been described somewhat in detail, forms no part of the present invention, but is shown, described and claimed in a co-pending application, Serial No. 529,242,, filed April 10, 1931.

When three needles are used, then three loopers areprovided, which enter the respective needle thread loops. The three loopers are indicated at 24, 25 and 26 in the drawings. Each is a thread carrying looper, and they are mounted for movements in a direction lengthwise of the workarm when theyv enter theneedle thread loops, and for movements in a direction laterally of the work arm and the line of feed, for their needle avoiding movements. The three loopers are all mounted on a single looper carrier 66. which looper carrier is shown more in detail in Figures 7 and 12 to 14, inclusive. The looper carrier is provided with upstanding arms 67 and 68,

which are preferably formed integral therewith. The loopers 24, 25 and 26 are placed between these arms, and a block 69 is shown in the drawings as placed alongside of the shanks of these'loopers, and takes the place of a fourth looper that might be used in this particular looper carrier. If two loopers are used, then an additional block is substituted for the looper which is taken out, and again, if one looper is used, still another block is substituted for the looper which is removed. The carrier is, therefore, adapted for any number of loopers from one to four. The loopers are all clamped rigidly to the carrier by two bolts 70 and 71 extending through the arm 68, the block 69, the loopers, and threaded into the arm 67. The looper carrier 66 is carried by a lever 72 which extends lengthwise of the work arm. The carrier is attached to a support 73 which is pivoted to the lever 72 by means of a pivot bolt 74. The support 73 carries a spring-pressed plunger 75 which makes locking engagement with a plate 76 attached to the end of the lever 72. This enables the support for the looper to be swung on the lever.' The work arm, as shown in Fig. 7, is provided with an opening in one side thereof which is closed by a cover plate 77. This cover plate is slid to one side, after which the latch or. plunger 75 is moved to the right by a handpiece 78, and thus the support is released so that it may be swung through the opening to 14; position the loopers where they may be readily reached for threading. When the looper support is returned to its normal position within the work arm, it is rigidly locked to the lever 72. The carrier 66 is mounted on the support 73 so that it may be shifted to different set positions in a direction endwise of the lever 72. The support 73 is provided with a dovetailed recess 79. The lower part of the looper carrier 66 has a similar shaped shank portion 80 which fits in said recess.

This permits the carrier to have a movement endwise of the support, but prevents any lateral movement or up. and down movement of the carrier on the support. The carrier is provided with a vertical slot 81 in the shank thereof. A pin 82 engages this slot 81. This pin 82 is carried by a cylindrical member 83 which has a slotted head whereby it may be readily turned. The cylindrical member is rotatably'retained in place by a pin 83 engaging an annular groove in said member. The pin- 82 is eccentrically mounted on this cylindrical member 83 so that when the member 83- is turned, the pin will move the carrier either to the right or left on the support, as viewed in Figures 12 to 14, depending upon the direction in which this cylindrical member 83 is turned. In Fig. 12 of the drawings, the looper is shown at one setting relative to the needle. It is held firmly locked in this set position by set screws 84 and 85 which are threaded through the support and bear against the shank of the carrier in the recess in the support. By loosening these screws, the cylindrical member may be turned to the position shown in Fig. 13, and this will set the looper a greater distance from the needle, and it may be then locked in this set position. In Fig. 14, the cylindrical member 83 is shown as turned to an intermediate position, which brings the looper closer to the needle for this particular setting of the lever on which the looper is mounted. Thus it is that positive means is provided for shifting the carrier to different set positions, and also means for positively locking the looper in its various set positions.

The looper supporting lever '72 isfulcrumed intermediate its ends so that it can both oscillate on its fulcrum and slide longitudinally thereon. This is accomplished by the means shown in detail in Fig. 9. There is a cylindrical fulcrum block 86 which is provided with a slot 87 extending diametrically therethrough. This slot is open at the top. This fulcrum block 86 is mounted in a housing block 88. Said housing block has a cylindrical recess 89 therethrough, in which this fulcrum block 86 is placed. The housing block 88 is provided with a slot 90 which extends all the way across, and the looper lever 72 extends through the slots 87 and 90. The looper lever is provided with wear plates 91, 91 at each side thereof in the region of this housing block 88 and fulcrum block 86. The slot 90 is of greater width than the slot 87. The looper lever moves endwise in both of these slots, and is free to move therein without turning the fulcrum block. The lever can be oscillated, turning the fulcrum block 86 in its seat in the housing block 88, and the slot 90 is of sufficient width to permit a limited range of oscillation. Mounted on top of the housing block 88 and covering the same is a cover plate 92. The plates 36 and 3'? at the sides of the feed levers have depending portions. The plate 36 is shown in Fig. 9, and the depending portions are indicated at 36 and 36 in this Figure. These depending portions are spaced so that when the plates are placed in the work arm, the depending portions extend along the ends of the side members of the housing block 88. The two plates 36 and 37, therefore, serve as the positioning means for this housing block 88 and its cover plate 92. The plates 36 and 37 are held in place by the pin 31 and this, of course, will hold the housing block 88 in a set position. It is sometimes desirable, as with different spacing of the needles, to shift the position of the fulcrum block 86 for varying the extent of movement of the looper.

It will be noted that the opening 93 in the plate 36 through which the pin 31 passes, is set at one side of the center of the plate 36. The same is true of the plate 37. If these plates are taken out and turned end for end, and then replaced, it will shift the position of the housing block 88 lengthwise of the lever '72 and this will in .tum shift the position of the fulcrum block 86. Other plates 36 with the depending portions 36' and 36 differently positioned relative to the opening 93 for the pin 31, as indicated in broken lines, may be substituted, in which case, of course, a housing block 88 of different length, and a cover plate 92, as indicated in broken lines in Fig. 9, would be used. By interchanging these parts and turning them end for end, the fulcrum block 86 may be shifted from one set position to another lengthwise of the looper lever. The pivot point on which this lever oscillates, although it is a shifting point, is centrally of this fulcrum block 86. v

In making the type of stitch for which this machine is designed, it is necessary for each looper to move in an orbit, the minor axis of which is equal to twice the distance between the centers of adjacent needles. The looper enters the needle loop at one side of the needle and then it is moved laterally for its needle avoiding movement so that the needle can pass down on the other side of the looper as it enters the looper thread loop. The looper must move a sufficient distance to clear the needle and in the present machine, in order to bring about the stitch formation described, the looper must move twice the distance between the centers of adjacent needles. This is to aid in the presenting of the looper thread loops of certain of the loopers for the entrance of two needles. In any case, the looper must not move so as to lie in the path of a needle. The purpose of shifting the fulcrum block for the looper lever is to vary the lateral extent of the movement of the loopers to accommodate different spacing of the needles. This is accomplished without changing the length of the stroke of the looper, which, of course, is determined by the endwise movement of the lever 72. In the lower diagrammatic view in Fig. 16, the fulcrum point for the looper lever is indicated at P. The extent of lateral motion imparted to the looper is indicated at :c. When the fulcrum point for the looper lever is shifted to the point P, that is, to a point nearer the looper, then the lateral movement imparted to the looper which is indicated at m, is less. On the other hand, when the fulcrum point is shifted to the position P in the diagrammatic view at the top of Fig. 16, then the lateral throw of the looper is indicated at as", and it is greater. It will be clear from the above that by shifting this fulcrum block, the lateral throw of the looper may be varied, and as noted, this does not change the extent of movement of the looper longitudinally of the work arm. In other words, it is the needle avoiding motion of the looper that is varied, and not the loop taking motion. Of course, the path of all the loopers will be similarly varied by this shifting of the fulcrum block 86.

The lever 72 carrying the loopers is provided with a wear plate 95 which is secured to the under face of the outer end of the lever 72. Attached to the inner face of the work arm is a wear plate 96, and these wear plates make contact which support this outer end of the looper lever. The

inner end of the looper lever rests on a wear plate 97 carried by a lug on the work'arm. A plate 98 overlies the inner end of the looper lever 72. Thus it is that the looper lever rests-on wear plates at the inner and outer ends thereof.

The looper lever '72 is given its movements from an eccentric member on the main actuating shaft 4. As shown, this eccentric member is in the form of a crank pin indicated at 99. The crank pin 99 is carried by a disk 100 on the right-hand end of the main actuating shaft. Directly connected to this crank pin 99 is a lever 101. which extends downwardly through the depending member 18 into the inner end of the work arm. This lever, as shown in Fig. 10, is provided with a recess 102 which is open at one side and is closed by a cover plate 103. There is a stationary fulcrum pin 104 with which fulcrum blocks 105, 105 cooperate, and these fulcrum blocks are mounted in the recess 102 engaging the inner side of the recess and the cover plate 103. This provides a means whereby the lever can be moved endwise and oscillated on this fulcrum pin 104. Thefulcrum pin 104 is carried by a cylindrical member 106 which is mounted in the outer wall 107 of the depending member 18. Said cylindrical member is provided with a flanged portion 108 which engages a seat in the inner face of the wall 107. A nut 109 threaded on to the outer end of a reduced portion 110 of said cylindrical member 106 serves as a means for clamping the cylindrical member in fixed positions. A washer 111 is provided which is located between the nut 109 and the seat at the outer face of the wall 107. At each side of the lever are guiding disks 112 and 113. The lever lies between these disks and is confined thereby to movements in a plane at right angles to the actuating shaft.

The lower end of the lever 101 is connected to a ball 114 slidably mounted on a stud 114 carried by an arm 115 formed as an integral part of a sleeve 116 which in turn is mounted on a shaft 117' for free oscillation and endwise movement thereon. The shaft 117 is mounted in bearing lugs, one of which is indicated at 118 in Fig. 5 of the drawings. This shaft is located at right angles to the longitudinal axis of the main shaft, and is, therefore, at an acute angle to the longitudinal axis of the work arm. The sleeve 116 carries a depending arm 119 with a stud at the lower end thereof on which a ball is slidably mounted and to which ball the inner end of the lever 72 is attached.

Referring to Fig. 15 of the drawings, the motions imparted to the looper by this eccentric member on the main actuating shaft, are diagrammatically illustrated. The center of the cylindrical member 106 is indicated at D. The center of the fulcrum pin 104 is indicated at the positions A, B and C. These are'different shifted positions of the fulcrum pin. By loosening the nut 109, this cylindrical member 106 may be turned to its center D, and the fulcrum pin 104 placed in any one of these three different positions indicated at A, B and C. It will be then fixed in this position, as the fulcrum pin has no movement during the operation of the machine.

Other set positions can also be obtained, if desired, but these three will be followed through in order to make clear the purpose of the shifting of the fulcrum pin 104. When the fulcrum pin is at the position A, then the lower end of the lever will move in an elliptical path, the extreme lower point of movement of which is indicated at A. This will cause the sleeve 116 to oscillate and also move endwise as the plane of movement of the lower end of the arm is at right angles to the longitudinal axis of the main shaft 4. The shaft carrying the sleeve 116 extends in a direction parallel to the plane of movement of this lever 101 in the depending arm. The ball on the lower end of the arm 119 will move substantially in a horizontal plane, and the path of movement is indicated in Fig. 15. When the point A is reached by the ball on the arm 115, then the ball carried by the arm 119 is at the point A". The looper at this time is practically at the extreme point away from the needle, and as the ball carried by the arm 119 follows its elliptical path of movement, the looper will move in a horizontal plane and in an elliptical path, the minor axis of which is determined by the position of the fulcrum point P of the lever 72. When the fulcrum pin 104 is shifted to the position B, then the path of movement of the ball carried by the arm 115 will be shifted so that at a similar time in its cycle of motion, it will be at the point B instead of at the point A. The ball at the lower end of the arm 119 will at this time be at the point B. The looper will now be shifted to the point B .due to the fact that the shaft 117 is set at an acute angle to the longitudinal axis of the work arm. The looper carrier is now shifted on the support therefor through the aid of the cylindrical member 83 to position the looper at the point 3*, so that its longitudinal path of reciprocation is properly placed for maintaining the timing between the looper and the needle.

When the fulcrum pin 104 is set at the position C, then the lower end of the lever will be at the point C instead of A or B, at a similar time in its cycle of motion. The ball at the lower end of the arm 119 will at this time be at the point C This will place the looper at the point C By shifting the looper carrier on the looper support, the looper may be brought back to the position 0*, and thus properly timed for cooperation with the needle.

It will be apparent from the above that by shifting the fulcrum pin 104, the working position or path of movement of the loopers may be shifted laterally. Means has, therefore, been provided in this lateral shifting of the fulcrum pin 104 and in the longitudinal shifting of the fulcrum block 86, so that the position of the path of travel of the looper can be varied without changing the character of the path of movement, and on the other hand, the character or extent of lateral movement imparted to the looper can be varied without varying the longitudinal or loop taking movement imparted to the looper. For all of these adjustments, the looper may be quickly brought into proper timing with the needle. It will also be apparent from the above description that the looper carrier may, at will, be shifted on the looper lever for setting the loopers relative to the needles to overcome any inaccuracies in length of loopers or the construction of other parts.

From the foregoing it will be noted that the looper motion is capable of adjustment to render the machine adaptable for seams of different character and width and to permit compensation for variations in the manufacture of parts and to facilitate the adjustment of the operating parts after assembling.

Cooperating with the loopers is the spreader 27. This spreader 27 is shown more in detail in Figures 6, 1'7, 18 and 19 of the drawings. The spreader 2'7 is secured to a member 120 which in turn is pivoted to a bracket 121 extending across from one side of the work arm to the other and supported thereby. This bracket lies directly over the looper lever and the looper support carried thereby. The member 120 carries a roller 122 which engages a cam plate 123 fixed to the looper lever. This cam plate is provided with arc-shaped spaced flanges 124, 125, and these flanges contacting with the roller will impart oscillations to the spreader. When the loopers move to the left as viewed in Fig. 9, these flanges 124, 125 will cause the spreader to move to the right, that is, in the opposite lateral direction from the direction of movement of the loopers. The curved flanges also impart a lateral movement to the spreader during the longitudinal movement of the looper lever. Thus it is that the spreader is given its proper oscillations so that the strands of the looper threads may be engaged thereby and carried away from the respective loopers, and properly positione for the needles to enter.

The spreader, as shown in Fig. 17, is provided with depending portions 27, 27', which in turn have laterally or horizontally extending portions 27', 27 The looper threads are engaged by these depending portions and pass over the horizontal portions against the inner wall 27 associated with each spreader. As shown in Fig. 17, the looper thread I is in engagement with the depending member at the left, while the two looper threads 1' and l are engaged by the depending member 2'7 at the right. The character of the stitch made is determined by the position of these depending members on the spreader, and the manner in which they engage the respective needle thread loops and position the same for the entrance of the needle. This spreader mechanism per se is shown, described and claimed in a co-pending application Serial No. 530,349, filed April 15, 1931.

In Figures 19, 20 and 21, one stitch formation on the machine as described is illustrated. The loopers are indicated at 24, 25 and 26, respectively. The looper thread loops are indicated at l, l and P. In Fig. 19, the spreader is shown as having engaged the strand of the looper thread loop. At this time, the loops in the needle threads 11, n and n are well back on the loopers, and the needles are descending so as to pass through the fabric and enter the desired looper thread loops for locking the same. In Fig. 20, the needles are indicated at 9, 10 and 11. The spreader, as shown in Fig. 19, engaged the looper thread 1 by one of its depending members and both the looper threads I and F by the other depending member. This positions thelooper thread loops so that the needles 9 and 10 both enter the looper thread loop of the looper 24. The needles 10 and 11 enter both of the looper thread loops of the loopers 25 and 26. In the position shown in Fig. 20, the loopers are being retracted and are about to shed the needle thread loops therefrom. In Fig. 21, the spreader is shown as having released the looper threads, and the loopers as having cast off the previously formed needle thread loops and as entering the newly formed needle thread loops. The loop in the looper thread I, as shown in this figure, is now around both the needles 9 and 10, and both the loop in the looper thread Z and the loop in the looper thread I are around both of the needles 10 and 11.

In Fig; 22 there is shown more or less diagrammatically the stitch formation above described used for forming a flat seam. The fabric section F overlaps the fabric section F. The central needle 10 passes through both fabric sections. The needle 9 passes through the fabric section F only, and the needle 11 passes through the fabric section F only. The covering thread is indicated at c. The looper thread loop 1 extends about the needles 9 and 10, and the two looper threads 1 and I extend about both needles 10 and 11. The raw edge I of the fabric section F is, therefore, covered by both of the looper thread loops Z, l. The. looper thread loop 1 joins the two needle thread loops on the under face of the fabric secions.

In Figures 23, 24 and 25, there is a slightly different stitch formation shown. The cam plate 123 has been slightly shifted so that the path of the spreader is bodily shifted to the left as viewed in Fig. 23. Consequently, one of the depending members 27' will engage the looper threads I and 1, while the other depending member will engage only the looper thread I. The depending portion 27 at the left of the spreader, as viewed in Fig. 23, engages the looper thread loops in both the looper threads I and 1', while the depending portion 27* at the right of the spreader engages only the loop of the looper thread F. In Fig. 24,-

the needles 9, 10 and 11 pass in the same relation to the loopers, and the needle 9 enters only the loop in the looper thread I. The needles 9 and 10 will both enter the loop in the looper thread 1, and the needles 10 and 11 will both enter the loop in the looper thread I". From Fig. 25, it will be apparent that the loop in the looper thread 1' is locked only by the one needle 9, while the loops in both the looper threads I and F are carried across and locked by both needles. Thus it is that the covering stitch is produced through these loops in the looper threads 1' and P which extend across and are locked by two needle loops on the next descent of the needles. The seam produced by this throw of the spreader is that shown and described in the patent granted S. George Tate, July 2, 1918, No. 1,271,241.

While the invention has been described as embodied in a looper mechanism wherein three loopers cooperate with three needles, it will be understood that a fourth looper may be added, in which case, of course, a fourth needle will be added, and the spreader will be provided with the proper depending portion for carrying the looper thread, so that it vn'll be entered by two needles. Then again, one of the needles may be removed and two needles only used, in which case, only two loopers will be necessary, and the spreader will be given such modification as may be necessary to bring about a proper stitch formation, wherein at least one of the looper threads is expanded and carried across so as to be entered by both of the needles 0n the next descent. also be obvious that from certain aspects of the invention, the looper mechanism may be used for operating a single looper, in which case only a single needle will be used. In each case, there is a separate looper cooperating with each needle, and the connected lines of stitching are produced by the expanding of the looper thread loops on the under face of the fabric, and by the connecting covering thread on the upper face of the fabric.

The bracket 121 which supports the spreader is extended laterally and provided with a head 129 which is grooved so as to provide needle guides for guiding the needles so as to insure the It will to facilitate the threading of the guides.

proper positioning of the needles for the loopers to pass the same.

The threads for the three needles are led through tensions and thence to a thread controller 131 and to suitable guides at the needle head and to the needles. The covering thread 0 is led through a tension 132 and thence to a separate thread controller 133 and to the thread guide associated with the cover thread laying mechanism. The needle threads and the covering thread pass through a guiding device 134 and to the controllers 131 and 133. After leaving the thread controllers, the threads pass through guiding eyes in a bar 135. There is a cover plate 136 covering a greater portion of the opening.

The looper threads are led through tensions 137 and thence through a thread guiding device 138 to a thread controller 139. The threads then pass through guide eyes in a bar 140 extending across an opening in the front wall of the main housing. The threads from this guide bar 140 pass downward to a thread guide 141 in the work arm. This thread guide has a vertical recess 142 therein, opening at the side of the guide. Four openings are shown leading horizontally from this center longitudinal recess through the side wall of the thread guide 141. These openings also lead all the way to the side of the thread guide so as to facilitate threading. It will be noted that there are projecting portions in this side wall which extend inwardly to different distances, so that the threads passing down through the central opening will be kept separated from each other, and then will turn at a right angle and pass along the work arm to the loopers. This thread guide 141 is mounted in a recess in the work arm, and can be raised and lowered by a pin 143 which is attached thereto and extends through a slot 144 in the work arm. Thus it is that the thread guide 141 may be raised in order As shown in Fig. 2, there is sufficient clearance between the lower edge of the cover plate 8 and the upper edge of the work arm 19 for threads to be inserted in the thread guiding slot formed in the wall of the work arm.

In order to eiiiciently lubricate all of the bearings of the machine, a supply reservoir 145 is provided for the lubricant. This reservoir is in the form of a pipe which is located within the upper horizontal member 3 and extends substantially from one end thereof to the other. There is a pipe 146 which leads from this main reservoir 145 to the bearing for the left-hand end of the main actuating shaft 4. There is a pipe 146 leading from the reservoir to the bearing for the needle lever. There is a pipe 147 leading from this reservoir 145 to a chamber 148 in a bearing 149 for the shaft 4. There is a pipe 150 leading from this reservoir to a chamber 151 in the bearing 152 for the main actuating shaft. There is a pipe 153 leading to a chamber 154 in the bearing 155 for the right-hand end of the main actuating shaft. In each of these chambers 148, 151 and 154, there is a short upstanding pipe 156 which leads through the bearing for lubricating the shaft. This pipe extends above the lower end of the chamber with which it is associated, as shown in detail in Fig. 2. Thus it is that the oil will accumulate in each chamber to a fixed level, and by the use of a packing, the oil is into the oil receiving pocket at the outer end of the strap. There is a similar pipe 158 which supplies oil to the eccentric strap cooperating with the eccentric 65. There is another pipe 159 which supplies oil to the crank pin 99. The oil dripping from the bearmgs will gather in the sump formed at the inner end of the'work arm. A hand-operated pump 160 is provided for pumping the oil from the sump back into the reservoir 145. The lubricating system for the machine will not be further described in detail, as it forms no part of the present invention, but is shown, described and claimed in a co-pending application Serial No. 529,214, filed April 10, 1931.

The operation of the machine will be obvious from the detail description which has been given. The machine is especially adapted for stitching small tubular articles formed by guiding the fabric section around the work arm so that the edges thereof may be joined. It is especially adapted for stitching knitted fabrics, and to this end it is provided with a differential feed and a trimming mechanism for preparing the edges which are to be joined. The stitch forming mechanism as illustrated includes three needles 00 with which three loopers cooperate, and a single cross thread laying mechanism, so that by the aid of seven threads, a very efficiently covered fiat seam is formed. The loopers move in a direction longitudinally of the work arm and 193 the under face of the fabric sections are covered by the expanding of the looper thread loops, so that they encircle adjacent needle thread loops. The edge portions of the fabric sections are preferably lapped in order to increase the 11 strength of the seam, the center needle passing through the lapped sections. Where three needles are used, the sections can be lapped to a short extent, and the needle which is centrally of the seam caused to pass through the lapped 115 sections. By the use of three needles, 3. very strong seam is produced, which seam is very narrow. The raw or cut edge of the under lapped section is covered by two looper thread loops which cross the same at each stitch formation. From certain aspects of the invention, four needles could be used, or two needles could be used, and covering seams produced which would be very efficient. While this machine has been described in detail as adapted particularly for 125 knit goods work where a flat seam is made and there are covering threads above and below, it will be obvious that the looper mechanism shown and described may be used for making one or more independent lines of stitching, in which 139 case, the trimming devices and the thread covering devices might be dispensed with. The operating means for the loopers and also for the feed dogs include parts extending lengthwise of the work arm, and therefore, the work arm may be 1 5 made of small cross sectional dimensions. They also include operating parts which are directly connected to the actuating shaft and extend downwardly through the depending member carrying the work arm, so that the number of connected parts and the angles about which said parts must transmit motion are reduced to a The work arm being suspended from a bracket and extending at an angle to the hori-- zontal member containing the main actuating 145 shaft, provides a machine wherein the fabric sections may be easily guided and a clear vision of the stitching point given the operator.

It will be obvious that minor changes in the details of construction and the arrangement of 150 the parts may be made 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. In a sewing machine, a supporting bracket, a horizontal member carried thereby, an actuating shaft in said member, a depending member at one end of said horizontal member, a work arin suspended at the lower end of said depending member, a looper in said work arm, a carrier for said looper, an oscillating and endwise moving lever extending lengthwise of said work arm on which said carrier is mounted, means located intermediate the ends of said lever providing an oscillating center for said lever, an oscillating and endwise moving lever in said depending member, means intermediate the ends thereof providing an oscillating center for said lever, means for transmitting the oscillating and endwise movements of the lever in the depending member to the lever in the work arm, and means carried by said shaft and directly connected to said lever in the depending member for imparting the endwise and oscillating movements to said lever.

2. In a sewing machine, a supporting bracket, a horizontal member carried thereby, an actuating shaft in said member, a depending member at one end of said horizontal member, a work arm suspended at the lower end of said depending member, a looper in said work arm, a carrier for said looper, an oscillating and endwise moving lever extending lengthwise of said work arm on which said carrier is mounted, means located intermediate the ends of said lever providing an oscillating center for said lever, an oscillating and endwise moving lever in said depending member, means intermediate the ends thereof providing an oscillating center for said lever, means for transmitting the oscillating and endwise movements of the lever in the depending member to the lever in the work arm, and means carried by said shaft and directly connected to said lever in the depending member for imparting the endwise and oscillating movements to said lever, said means in the work arm being shiftable for varying the center of oscillation of the lever controlled thereby.

3. In a sewing machine, a supporting bracket, a horizontal member carried thereby, an actuating shaft in said member, a depending member at one end of said horizontal member, a work arm suspended at the lower end of said depending member, a looper-in said work arm, a carrier for said looper, an oscillating and endwise moving lever extending lengthwise of said work arm on which said carrier is mounted, means located intermediate the ends of said carrier providing an oscillating center for said lever, an oscillating and endwise moving lever in said depending member, means intermediate the ends thereof providing an oscillating center for said lever, means for transmitting the oscillating and endwise movements of the lever in the depending member to a the lever in the work arm, and means carried by said shaft and directly connected to said lever in the depending member for imparting the endwise and oscillating movements to said lever, said means in the work arm including shiftable and interchangeable parts for varying the center of oscillation of the lever controlled thereby.

4. In a sewing machine, a supporting bracket, a horizontal member carried thereby, an actuating shaft in said member, a depending member at one end of said horizontal member, a work arm suspended at the -'lower end of said depending member, a looper in said work arm, a carrier for said looper, an oscillating and endwise moving lever extending lengthwise of said work arm on which said carrier is mounted, means located intermediate the ends of said lever providing an oscillating center for said lever, an oscillating and endwise moving lever in said depending member, means intermediate the ends thereof providing an oscillating center .for said lever, means for transmitting the oscillating and endwise movements of the lever in the depending member to the lever in the work arm, means carried by saidshaft and directly connected to said lever in the depending member for imparting the endwise and oscillating movements to said lever, said means in the work arm including a cylindrical fulcrum member in which said lever moves endwise, and devices for supporting said member whereby the same may oscillate.

5. In a sewing machine, a supporting bracket, 9. horizontal member carried thereby, an actuating shaft in said member, a depending member at one end of said horizontal member, a work arm suspended at the lower end of said depending member, a looper in said work arm, a carrier for said looper, an oscillating and endwise moving lever extending lengthwise of said work arm on which said carrier is mounted, means located intermediate the ends of said lever providing an oscillating center for said lever, an oscillating and endwise moving lever in said depending member, means intermediate the ends thereof providing an oscillating center for said lever, means for transmitting the oscillating and endwise movements of the lever in the depending member to the lever in the work arm, means carried by' said shaft and directly connected to said lever in the depending member for imparting the endwise and oscillating movements to said lever, said means in the work arm including a cylindrical fulcrum member in which said lever moves endwise, devices for supporting said member whereby the same may oscillate, and interchangeable devices for shifting the oscillating position of said membet.

6. In a sewing machine, a supporting bracket, a horizontal member carried thereby, an actuating shaft in said member, a depending member at one end of said horizontal member, a work arm suspended at the lower end of said depending member, a looper in said work arm, a carrier for said looper, an oscillating and endwise moving lever extending lengthwise of said work arm on which said carrier is mounted, means located intermediate the ends of said lever providing an oscillating center for said lever, an oscillating and endwise moving lever in said depending member, means intermediate the ends thereof providing an oscillating center for said lever, means for transmitting the oscillating and endwise movements of the lever in the depending member to the lever in the work arm, and means carried by said shaft and directly connected to said lever in the depending member for imparting the endwise and oscillating movements to said lever, said means in said depending member being shiftable for varying the center of oscillation of the lever controlled thereby.

'1. In a sewing machine, a supporting bracket, 9. horizontal member carried thereby, an actuating shaft in said member, a depending member at one end of said horizontal member, a work arm

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