US2332087A - Rotary take-up for sewing machines - Google Patents

Description

Oct. 19, 1943. J. D. KARLE ROTARY TAKE-UP FOR SEWING MACHINES Filed Feb. 12, 1941 6 Sheets-Sheet l mm NQWN a N i m MN H N |l|l 2....1 l] 6% QM uw w j %N mm mm 1 a 'H F W m a i- Z/ J N 0% QM Jo/zn ZZAarZe W. MN m MW g k QR mm 3 Wm. mm EN mN NR w. MQN Sn km W w Oct. 19,1943. J. D. KARLE ROTARY TAKE-UP FOR SEWING MACHINES Filed Feb. 12, 1941 6 Sheets-Sheet 2 John D. Karla any/mug Oct. 19, 1943.

J. D. KARLE ROTARY TAKE-UP FOR SEWING MACHINES Filed Feb. 12, 1941 6 Sheets-Sheet 3 1943. J. D. KARLE 2,332,087

ROTARY TAKE-UP FOR SEWING MACHINES- Filed Feb. 12, 1941 6 Sheets-Sheet 4 ail/0W John 17. Karla 3 Q 7% firm/W Oct. 19, 1943.

J. D. KARLE ROTARY TAKE-UP FOR SEWING MACHINES 6 Shee'ts-Sheet 5 Filed Feb. 12, 1941 Oct. 19, 1943. D, KARLE 2,332,087

ROTARY TAKE-UP FOR SEWING MACHINES Filed Feb. 12, 1941 6 Sheets-Sheet 6 Patented Oct. 19, 1943 UNITED STATES PATENT OFFICE ROTARY TAKE-UP FOR SEWING MACHINES John D. Karle, Roselle Park, N. J., assignor to The Singer Manufacturing Company, Elizabeth, N. J, a corporation of New Jersey Application February 12, 1941, Serial No 378,496

29 Claims. (Cl. 112-248) This invention relates to thread take-ups for sewing machines. 7

In a lock-stitch sewing machine having a reciprocatory eye-pointed needle and a complementai rotary hook and bobbin-thread-case device, it is necessary to have a needle-thread take-up having a fast take-up action timed to occur. immediately after the rotary hook reaches needleloop cast-01f. position. The take-up must then have a comparatively slow slack giving action as the needle descends through the work preparatory to the presentation of a new needle-loop to the rotary hook.

A simple rotary take-up has long been recognized as having the very desirable attribute of being perfectly balanceable for quiet, vibrationless operation at high speeds, as by the simple expedient of adding weight, where needed, to bring it into balance. A simple rotary take-up having a single circularly moving thread-engaging member, however, does not possess the relacompound rotary take-up having no shaft which tively fast take-up and slow slack-giving actions desired. Compound rotary take-ups have heretofore been proposed to secure the desired fast and slow actions, such take-ups including a second thread-engaging member movable differentially with relation to the primary circularly moving thread-engaging member.

Of the compound rotary take-up heretofore devised with the desired fast and slow thread-handling characteristics, none has been perfectly balanceable, except the double-disk type having two take-up elements rotating at different speeds. While a take-up of this latter type has the desired fast and slow thread-handling characteristics, it requires two rotary shafts for its operation and one of these shafts must run in its bearings at a speed which is at least double the speed of the needle-driving shaft of the sewing machine.

The present invention' has for an object to provide a simplified, compact and perfectly balancedtake-up which meets the fast thread takeup and slow thread-delivery requirements of highspeed lock-stitch sewing machin operation. Another object of the invention is to provide a sewing machine thread take-up of the compound rotary type including two concomitantly and differentially acting thread take-up elements operating in perfect balance and actuated by simplified driving mechanism enabling the take-up to be assembled as a unit independently of the sewing machine and applied to or removed from the machine as a unitary assembly. A further object of the invention is to provide a balanced greater than the sewing speed of the needledriving shaft of the machine.

A still further object of the invention is to provide a take-up which may be quickly and easily adjustable to vary the timing of the beginning of the take-up action relative to the looptaker.

With the above and other objects in view,' as will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of .a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

Fig. 1 is a vertical sectional view taken through a sewing machine embodying my invention.

Fi 2 is a rear elevation of the machine shown in Fig. 1.

Fig. 3 is an enlarged sectional view taken through the head of the machine. a Fig. 4 is a head end elevation of the machine shown in Figs. 1 and 2.

Fig. 5 is a section taken substantially along the line 5-5 of Fig. 4.

Fig. 6 is an inside face view of the rotating take-up elements.

Fig. 7 is a perspective view of the fan for cooling the take-up elements.

Figs. 8-16 are face views of the machine showing the position of the take-up element during a complete stitch-forming cycle.

Figs. 17 and 18 are a top plan and front elevation, respectively, of a portion of the head of the machine with a transparent plate attached thereto which may be used to enclose the takep.

In the embodiment of the invention selected for illustration my invention is shown embodied in a sewing machine of the kind shown in the patent to R. Kaier, No. 2,206,285, dated July 2, 1940.

As shown, the machine comprises a bed ill from which rises a standard ll carrying an overhanging armlZ terminating in a head 13. Journaled in suitable bearings I4 is a needle-bar actuating shaft I5 having a balance-wheel and driving pulley l6 secured to one of its ends. Secured to the shaft 15 is a bevel gear I! which meshes with the bevel gear l8 carried by a vertical shaft l9 journaled in the bearings 20. The

shaft l9 carries a second gear 2| which meshes with a gear 22 fixed to the end of the hookshaft 23 which is Journaled below the bed in the bearings 24, the hook-shaft 23 rotating twice for each rotation of the needle-bar shaft I5. Actuated by the vertical shaft I9 is an oil-pump 25 which i connected with the middle bearing H for the shaft I by a conduit 28 for th purpose of supplying oil under pressure to a bore in the shaft |5. The shaft l5 also carries the eccentrics 29 and 30 which through the pltmans 3|, 32 and the usual connections imparts to the feed-dog 33 its four components of motion.

Fixed to the end of the shaft l5 which extends into the hollow head I3 is a crank-disk 35 carrying a crank-pin 36 which is embraced by a hub 31 on one end of the needle-bar link 38, the other end of the link being operatively connected with the vertically reciprocatory needle-bar 38 by the pivot-stud 40. The needle-bar is journaled in the bearings 4|, 42 and carries an eye-pointed needle 43 which cooperates with the rotary hook 44, fixed to the shaft 23, in the formation of lockstitches. The mechanism described above it all old and well known and is fully described in the patent to R. Kaier, No. 2,206,285, dated July 2,

1940, to which reference may be had for a more end of the bushing 45 and a member 52, secured to the presser-bar 41. For the purpose of preventing the presser-bar 41 from turning about itslongitudinal axis in its bearing the member 52 is formed with a rearwardly extending portion 53 (Fig. 5) which extends into the slot 54 formed in the head I3. The presser-bar may be raised by the lifting lever 55 which is fixed to one end of a pivot-pin 56 Journaled in the head l3 (Figs. 2, 4 and 5). To the end of the pivotpin 56 which extends into the hollow head |3 there is fixed a cam 51 which is located beneath the laterally extending arm 58 of the member 52. From the above it will be obvious that when the hand-lever 55 is raised the pin 58 will turn about its longitudinal axis and turn the cam so that it will engage the under side of the arm 58 and raise the presser-bar 41. The presser-bar may also be raised by other means herein shown as a rod extending upwardly through the bed l0 and having its upper end fixed to one end of the flexible cable 6| which lies over the pulleys 62 Journaled on the arm l2. The other end of the cable extends through an aperture inone of the limbs of the Z-shaped member 63 fixed to the presser-bar 41, there being provided a ball 84 on the end of the cable 6|. With this construction the presser-bar may be raised and lowered by the hand-lever and the member 63 will slide along the cable 6|, thereby eliminating interference between the two raising means for the presser-bar. The rod is operated by the pivoted lever 80' which is actuated by a kneeshift lever as shown in the Kaier patent. The member 63 is also provided with a suitable aperture which receives the rod 65 formed with a depending end 66 which acts as an edge guide for the work. It is obvious that the guide may be adjusted laterally relative to the preser-foot 48 and that it may be shifted from operative to inoperative position by simply turning the rod 65 about its longitudinal axis.

The link-type take-up shown in the Kaier patent has been replaced by mechanism comprising a spiral gear 10 fixed to the shaft |5 which meshes with a second spiral gear 1| fixed to one end of a shaft 12 which extends through and is journaled in the bearing 13 carried by the overhanging arm I2 of the machine. The shaft 12 extends through the hollow head and through a ball bearing 15 carried by the coverplate 16 which is fixed to the hollow head by the screws 11. The plate 16 is formed with an aperture through which the shaft extends and around the aperture the plate 16 extends forwardly forming a sleeve-like portion 18 which is embraced by a stationary sun'gear 19 fixed by a screw to the plate. From the above it will be understood that the shaft 12 extends through the stationary gear 19 and is adapted to rotate relative thereto.

Fixed to the end of the shaft 12 and rotatable therewith is a disk 82 carrying a ball-bearing 83, the inner race of which carries a member 84 having a reduced end portion 85 which is embraced by the metal insert 88 of a fiber planetgear 81 which meshes with the stationary sungear 19. The ratio of these gears is as 1 is to 1. Extending into the hollow end of the member 84 is the hub of a small disk 89. The gear 81, member 85 and disk 89 operate as a unit and are rigidly clamped in assembled relationship by a bolt 90 which extends through the hub of the disk 89, and the member 85, the threaded end of the bolt being received by a nut 9| which is fixed to the metal insert 86 of the gear 81 by pins 92. Carried by the disk 89, at a distance from its axis of rotation, is a thread-engaging element or stud 93 which supports a thread-guide or guard 94 (Fig. 4) which extends across the axis about which the disk, 89 rotates and has the end opposite the stud 93 flared outwardly to form a. counterweight for the stud 93 and thus place the disk 89, stud 93 and guard 94 in balance.

I The large disk 82 carries two spaced threadengaging elements 96 and 91 each of which is in the form of a collar and these elements are held clamped between the outer guard disk 98 and the disk 82 by the screws 99 (Fig. 4). The disk 98 is held in spaced relation to the disk 82 by the elements and 91 and the inner face of the disk 98 is in the same vertical plane as the inner face of the guard 94. The small disk-89 is set into the disk 82 so that their outer faces are in the same vertical plane. This construction affords a guiding channel I00 (Figs. 1 and 3) for the needle-thread.

To place a slight pulling action on the thread at certain points in the stitch-forming cycle the disk 98 is provided with two openings into which the shouldered buttons 02 and I03 are set. shown in Fig. 3 these buttons are formed wi a curved head in the form of a segment of a sphere and each button is constantly urged against the disk 82 by a light spring I04. From the above it will be obvious that thread in the channel )0 will wipe between these buttons and the face of the disk 82 each time the take-up is rotated and a slight pull on the thread will cause the buttons to move towards the disk 98 against the action of the spring 14 and thereby permit the thread to pass.

From the foregoing it will be understood that the disk 82 may be pressed onto the knurled end of the shaft 12 and the remaining parts assembled on the disk. The entire assembly is then v assaoe'r placed in operative position on the machine by insertin the end of the shaft 12 through the Y protruding sleeve-like portion 19, ball bearing 18,

bearing 18. The thrust washer 18 and gear 1i are slipped over the end of the shaft as it is be ing inserted and after the parts are all in place the disk 82 is set to theproper point for timing and the gear 1i is then looked in position on the shaft. It will be understood that access to the end of the shaft 12 for the purpose of placing the gears in operative position is had through the cover-plate 2 which is held on the top part The lead of the needle-thread T is from the source of supply to the thread-guide Ill, thread tension H8, check spring II8, guide 1, the channel I between the disks 82 and 98, the guides H8, H9 and thence to the needle. Assuming the parts to be in the position shown in Fig. 8, the needle at this point in the stitchforming cycle is in its lowest position and the thread-controlling elements 93, 88 and 91 as well as the button I03 control the amount of slack in the needle-thread. When the machine is operated the shaft I5 rotates in a clockwise direction and through the gears 10, 1i the shaft 12 is rotated in a counterclockwise direction as viewed in Fig. 4. The disk or carrier 82, being fixed to the shaft 12, also rotates in a counterclockwise direction and carries with it the primary take-up elements 98 and 91. As the disk 82 also carries the disk 89 to which is fixed the secondary take-up element 93 the disk is rotated about the axis of the shaft 12 and due to the stationary gear 19, which meshes with the gear 81 fixed to the disk 89, the disk 89 also rotates about the axis of the member 88. The threadcontrolling element 93 is thus caused to execute an epithrochoidal movement.

The parts being in the position shown in Fig. 8 the first few degrees of motion of the needlebar shaft I5 cause the parts to assume the positions shown in Fig. 9. In this position the needle has been slightly raised to form a loop and the hook is just entering the loop. The lead of the thread is from the guide II1 across the button I03, the controller 98 and one of the primary take-up elements 81. After the loop has been taken, as shown in Fig. 10, the controller 93 and the take-up element 91 will give up thread, and as the thread is being detained by the button I03 some additional thread can be obtained by drawing the thread under this button. In Fig. 11 the loop-taker has traveled about 90 passed loop-seizing position, the thread at this time having been pulled from under the button I08 so that it is now detained by the button I02 and the controller 98 continues to give up thread. At this point the primary take-up element 96 is beginning to take a small amount of thread. Fig, 12 illustrates the position of the thread just before the hook of the loop-taker has reached 180. At this point of the cycle the thread has been pulled from under the button I02 and is now controlled entirely by the primary take-up element 98 which is taking up thread and the controller 93 which is giving up thread at this particular point of the cycle of operation. Fig. 18 represents one of the critical points in the stitch-forming cycle i. e. the point at which the needle-loop begins to slip over the beak of the hook. At this point the primary take-up element 98 is taking up thread and the secondary element 99 continues to give up thread. The amount of thread taken up by the element 98 is slightly more than the amount given up by the controlling element 98 with the result that there is a slight tightening of the thread at this point which causes the thread to slip along the hook-beak as shown in Fig. 14.

Between the positions shown in Figs. 12 through 14 the take-up action of pin 98 is practically balanced by the give up action of the controller element 98. This is the beginning of a very rapid take-up action and as illustrated the primary take-up element 98 is taking up thread and the primary element 91 is Just engaging the thread to begin its take-up action while the element 93 is still giving up a small quantity of thread. Fig. 15 illustrates the position'of the parts after the loop has left the beak or the hook and is now on the loop-controlling tail of the hook. At this point of the cycle the primary take-up elements 98 and 91 control the take-up action and the controlling element 99 has no function. Fig. 16 represents the stitch setting point in the cycle. At this point the thread is drawn taut across the two take-up elements 98 and 91 which are at the peak of their take-up action and the stitch is Q set in the material. The stitch setting action is very gentle in that the last few degrees of movement of the take-up elements 98 and 91 pull only a small amount of thread through the needleeyes; from this it would be seen that the stitch setting action occurs slowly and gently and properly anchors the stitch in the material.

From the foregoing it will be observed that the controller 99 does not act to set the stitch, this important function is accomplished by the take-up elements 98 and 91. The controller 98 begins to function shortly after the stitch is set at which time it takes up the slack thread. Its

most important function is to give up thread when the take-up element begins its take-up action. This delays the time of the beginning of the take-up action of the primary elements and reduces the time required for the take-up action. In the present instance the take-up and stitch setting action occurs in about 127 of motion of the take-up elements 98 and 91. As the stitch setting point is not effected by the element 98 it will be obvious that it may be adjusted to vary the beginning of the take-up action by the elements 98 and 91 to coordinate it with the beginning of the cast 0d of the rotary hook. This is accomplished by loosening the screw and then turning the disk 89. which carries the controller 98, relative to the gear 91. If it is turned counterclockwise, as viewed in Fig. '4, the start of the take-up of the needle-loop will be delayed; and if it is turned in a clockwise direction the take-up of the needle-loop will begin earlier. In this way variation in the machines and irregularities in the manufacture of the hook may be overcome. The timing of thetake-up elements 98 and 91 may also be varied. This is accomplished by loosening the set screw 1! which fixes the gear H to the shaft 12 and then turning the disk 82 relative to the gear 1|. This, of course, will change the relation of the take-up elements to the position of the hook 44. From the above it will be seen that the take-up can be readily and easily adjusted to meet varying conditions which may occur during the manufacture of the machine.

Another important feature is the rotation of the element 93 within the orbit described by the primary take-up elements 90 and 91. It will be noted that the element 93 moves towards and away from the elements 90 and 91 and as the element 98 is within the orbit described by the elements 98 and 91 if the thread should break and begin to wind about the elements, the motion of the element 93 towards and away from the other elements will break the needle thread and prevent it from winding about the elements.

It will be understood that the buttons I02 and I03 serve only to take-up surplus needlethread slack and that the take-up will operate without the use of the buttons and consequently they are not considered to be essential'to my invention. I have shown in Figs. 17 and 18 a covering which may be used to enclose parts of my improved take-up. As shown the covering comprises a hinge I2I for pivotally securing a disk of transparent material I22 to the plate I6. This transparent material is provided at a point diametrically opposite the hinge with a spring catch I23 which is adapted to engage the other side of the plate I and hold it in position. It will be obvious that the disk I22 may swing about its pivot I2I to provide access to the take-u and that the needle thread may be slipped into channel I00 between the take- up disk 82 and 98 for the purpose of threading the take-up.

I am aware of the prior rotary take-ups of U. S. patents No. 923,031 of May 25, 1909, and No. 1,941,943 of Jan. 2, 1934. Each of these take-ups, however, has only one movable takeup element, as distinguished from two take-up elements movable differentially relative to each other, as in the take-up herein claimed. These two prior take-ups do not effect the required nicety of thread control essential to the highspeed operation of the modern dry-thread lockstitch sewing machine.

I am also aware of the prior take-up of U. S. Patent No. 1,941,942 of Jan. 2, 1934, but this take-up embodies a reciprocatory slide to carry one of two differentially movable take-up elements and is not perfectly balanceable. Furthermore, it is designed for use with a wax-thread hooked-needle lock-stitch sewing machine of the shoe-sole sewing type which runs at a comparatively low speed.

I do not claim any of the constructive features of the prior take-ups discussed above.

Having thus set forth the nature of the invention what I claim herein is:

1. A compound rotary take-up for sewing machines having, in combination, a rotary carrier, a circularly moving primary thread take-up element carried thereby, a planet-wheel journaled in said carrier, a thread-controller actuated by said planet-wheel, and a stationary sun-wheel connected to operate said planet-wheel by rotation of said carrier.

2. In a sewing machine, a thread-controlling element, a carrier having a bearing in which said thread-controlling element is journaled, means to rotate said carrier about an axis offset from the axis of said bearing, means to rotate said controlling element at a uniform angular veloc ity in said bearing, and a second thread take-up element carried by said carrier.

3. A compound rotary take-up for sewing machines comprising, in combination, a rotary thread-controlling element, one-toone sunand-planet gearing for actuating said element, said gearing including a planet member and a rotary carrier therefor, and a rotary take-up element fixed to said rotary carrier.

4. In a sewing machine, a rotary thread-controlling member, a bearing therefor, carrier means to move said bearing around a field, means to rotate said member relative to its bearing at a uniform angular velocity, and a rotary thread take-up member fixed relative to said carrier means.

5. A sewing machine thread take-up device comprising, a pair of rotary shafts having spaced parallel axes, rotary means to carry one shaft about the axis of the other shaft, means to continuously rotate said one shaft about its own axis and relative to said rotary means, and two thread-engaging elements carried, respectively, by said shafts.

6. A compound rotary take-up for sewing machines having, in combination, a primary shaft, a primary thread-engaging member carried thereby and traversing a path concentric with said shaft, a secondary shaft journaled eccentrically to said primary shaft and carried by the latter, a secondary thread-engaging element carried by said secondary shaft, and means to continuously and unidirectionally rotate said secondary shaft about its own axis as said axis is carried around a field by rotation of said primary shaft.

7. A sewing machine thread take-up device comprising, a continuously rotating primary thread-engaging element, a secondary threadengaging element continuously rotatable in one direction about an axis spaced from the axis of rotation of said primary thread-engaging element, and means to carry the axis of rotation of said secondary thread-engaging element around a field.

8. A sewing machine thread take-up device comprising, a continuously rotating primary thread-engaging element, a secondary threadengaging element continuously rotatable in one direction about an axis spaced from the axis of rotation of said primary thread-engaging element, and means to carry the axis of rotation of said secondary thread-engaging element around a circular field the center of which lies in the axis of rotation of said primary thread-engaging element.

9. A compound rotary take-up device for sewing machines having, in combination, two spaced parallel shafts, a bearing for one of said shafts, means to rotate said bearing about the axis of the other shaft, thread-engaging elements carried. respectively, by said shafts, and means to unidirectionally drive said shafts in timed relation to one another.

10. A take-up device for sewing machines having, in combination, a primary thread-engaging device, means to move said device in a circular path, a secondary movable thread-engagin vice, epicycloidal gearing for imparting an epitrochoidal movement to the latter, and means'to uide a thread relative to said primary and secondary devices for their concomitant action thereon.

11. A compound rotary take-up device for sewing machines comprising, a stationary sungear, a planetary gear meshing with said stationary sun-gear, a carrier for said planetary gear, a primary thread-engaging element fixed relatively to said carrier, and a secondary thread-engaging rotate said auxiliary thread-engaging element in a circular path in said first-mentioned bearing.

13. In a sewing machine, in combination, a thread-controller, a bearing therefor, a rotary carrier for said bearing, a bearing for said rotary carrier axially offset from said first mentioned bearing, a thread take-up element carrried by said carrier, means to continuously rotate said carrier in said last mentioned bearing, and means to continuously rotate said thread-controller in and relative to said first mentioned bearing, said take-up element and controller being relatively timed each to execute one complete rotation in its respective bearing in the same time interval.

14. A sewing machine thread take-up device comprising, two rotary crank take-up elements, relatively offset bearings therefor, means to carry and so move one of said bearings that its axis travels in an orbit around the axis of the other bearing, and means to unidirectionally rotate each take-up element in its respective bearing.

15. A sewing machine having a frame including a bed and an overhanging bracket-arm terminating in a head, a reciprocatory needle-bar journaled in said head, a needle-bar-operating shaft Journaled in said bracket-arm, said head being formed with a circular recess, a needle-thread take-up device including a casing fitted to said circular recess, a shaft journaled in said casing and carrying a disk having thread take-up means journaled therein and means for removing said casing and take-up means from said head as a unit.

16. A rotary take-up for sewing machines comprising, a primary shaft, a disk carried thereby and concentric therewith, a take-up element fixedly positioned on said disk, a secondary shaft Journaled in said disk in parallelism with and spaced from the axis of said primary shaft, a thread-controller carried by said secondary shaft, a gear on said secondary shaft, and an externally toothed stationary gear coaxial with said primary shaft and operatively connected with said firstmentioned gear.

17. A compound rotary take-up for sewing machines having, in combination. a pair of spaced disks, and circularly moving primary and epitrochoidally moving secondary take-ups running in the space between said disks.

18. In a compound rotary take-up for sewing machines, the combination with a circularly movable thread-engaging member, of an apitrochoidally movable thread-engaging member, and means to guide a thread to said members for their concomitant action thereon.

19. In a compound rotary take-up for sewing machines, the combination with a circularly movable thread-engaging member, of an epitrochoidally movable thread-engaging member, arranged to circumscribe a field about the axis oi revolution of said circularly movable take-up'member.

20. A compound rotary take-up for sewing machines having, in combination, a stationary sungear, a planet gear, means to revolve said planetgear about the axis of said sun-gear. a driving connection between said sun and planet-gears for revolving the latter about its own axis in timed relation with its period of revolution about the axis of said sun-gear, a thread-controlling mem-- ber secured to said planet-gear and offset from the axis of the latter, a thread-engaging member movable circularly about the axis of said sungear, and means to guide a thread to said threadengaging members for their Joint action thereon.

21. A compound rotary take-up for sewing machines having, in combination. a stationary sungear, a planet-gear, means to revolve said planetgear about the axis of said sun-gear, a driving connection between said sun and planet-gears for revolving the latter about its own axis in timed relation with its period of revolution about the axis of said sun-gear, a thread-controlling member secured to said planet-gear and offset from the axis of the latter, means for adjusting said controlling member relative to said planetgear, a thread-engaging member movable circularly about the axis of said sun-gear, and means to guide a thread to said thread-engaging members for their Joint action thereon.

22. A rotary thread take-up for sewing machines having, in combination, a primary threadengaging member rotatable about a primary axis,

a secondary thread-engaging member, and means form angular velocities about their respective axes, including means to carry one of said axes about a field.

24. A take-up for sewing machines having a reciprocatory needle and a rotary hook formed with a looping seizing beak comprising primary thread-engaging members which are adapted to pull the needle-thread-loop from the beak of the hook and set the stitch, a secondary thread-engaging member, and means to vary the timing of the secondary thread-engaging member relative to the primary thread-engaging members to thereby control the time at which the primary thread-engaging members become eflective to begin to pull the needle-thread loop from the beak of the hook.

25. A sewing machine having'in combination, an eye-pointed needle, a rotary hook cooperating with said needle, means for actuating said needle and hook, rotary take-up elements for pulling the thread-loop from the hook and setting the stitch, a rotary thread-engaging member, and

means to vary the timing of said thread-engaging member relative to said rotary take-up elements for controlling the point in the stitchforming cycle at which the pulling action of th take-up begins.

26. In a sewing machine having a reciprocat- .ing needle and a loop-taker cooperating thereing the timing of said controlling member relative to the thread-engaging elements to thereby control the time at which the thread-engaging elements will begin their take-up action.

27. In a sewing machine having a reciprocating needle and a loop-taker cooperating therewith to produce lock-stitches the combination of, rotary thread-engaging elements for taking up the needle-loop after it is cast oil! by the looptaker and drawing the thread up to set the stitch and a controlling member for determining the time at which the thread-engaging elements will begin their take-up action, and means for adjusting the control member to vary the time at which the take-up action begins.

28. A take-up for a sewing machine comprising, a member rotatable about an axis, take-up elements carried thereby, a gear fixed to the machine with its central point in line with the axis about which the member rotates, a thread-controller carried by said member, a gear secured to said thread-controller and meshing with the first mentioned gear. and means for adjusting said controller relative to said last mentioned gear.

29. In a compound rotary take-up for sewing machines the combination with a circularly movable thread-engaging member, of an epitrochoidally movable thread-engaging member, means to guide a thread to said members for their combined action thereon, and means for shifting the path or movement of the epitrochoidally movable member relative to the circularly movable member.

JOHN D. KARLE.

Images