US3030788A - Method and apparatus for yarn end control - Google Patents

Description

April 24, 1962 R. PEEL 3,030,788

' METHOD AND APPARATUS FOR YARN END CONTROL Filed April 28, 1959 2 Sheets-Sheet 1- April 24, 1962 R. PEEL 3,030,788

METHOD AND APPARATUS FOR YARN END CONTROL Filed April 28, 1959 2 Sheets-Sheet 2 3,030,788 METHOD AND APPARATUS FOR YARN END CONTROL Robert Peel, Philadelphia, Pa., assignor, by mesne assignments, to Singer Fidelity, Inc., Philadelphia, Pa, a corporation of Delaware Filed Apr. 28, 1959, Ser. No. 809,439

17 Claims. (Cl. 66-140) The present invention relates to yarn end control apparatus, and more particularly to apparatus of this type for circular knitting machines.

The invention provides a device which removes the yarn ends severed when putting yarns into and out of action, and which also straightens and tensions the yarn ends passing through the inactive yarn fingers, so that when such yarns are put into action the yarn operates satisfactorily.

Standard circular knitting machines employ yarn cutters for severing the leading ends of the inserted yarn, and the trailing end of the withdrawn yarn to prevent excessive lengths of yarns from being carried with the circular knit fabric, thereby eliminating the necessity for trimming the excesive lengths in a subsequent operation and preventing the excessive lengths from being inadvertently knitted into the fabric to form slubs or the like. It is therefore desirable to sever the yarn'closely adjacent the needle circle, and at the same time remove the separated portion of the yarn end to prevent it from fouling the operation of the knitting machine and the severing device, especially when an eleetro-thermal severing device is used.

Prior to the present invention, the severed yarn ends were removed from the dial plate by a suction device having a nozzle overlying the dial plate adjacent the cutter. In normal operation, such devices operate satisfactorily but are expensive to install and maintain, and also obscure the operation of the yarn severing and clamping mechanism on the dial plate.

With the foregoing in mind, the present invention provides a novel yarn-end control apparatus which eliminates the necessity for suction nozzles overlying the dial plate, and which cooperates with the severing device to remove the severed yarn ends. More particularly, the present invention provides a device which may be mounted on the dial plate at a position remote from the severing means, without obstructing the operationof the mechanism of the dial plate.

The present invention simplifies the clamping means by exerting proper tension on all of the inactive yarns throughout their periods of inactivity; more specifically, the present invention provides a yarn take-up operable to be connected with each of the inactive yarns to form a multi-yarn strand, which is advanced upon each insertion or withdrawal to straighten and tension the inactive yarns, as well as being operable to pick up and entrain the severed yarn end in the strand to remove the same from the severing device.

All of the objects of the present invention are more fully set forth hereinafter in thedescription of the construction and operation thereof, with reference to the accompanying drawings wherein:

FIG. 1 is a fragmentary perspective view of the knitting machine head, made in accordance with the invention, showing the yarn paths across the dial plate;

FIG. 2 is a fragmentary plan View of the apparatus shown in FIG. 1;

FIGS. 3, 4 and are sectional views taken on the lines 3*3, 4-4, and 5-5 of FIG. 2, FIGS. 4 and 5 being enlarged;

FIG. 6 is an inverted plan view as seen from the line 6-6 of FIG. 5;

fi fifl Patented Apr. 24, 1962 FIG. 7 is an elevational view, partially in section, of the preferred embodiment of yarn take-up means in accordance with the present invention;

FIG. 8 is a sectional view taken on the line 8-8 of FIG. 7;

FIG. 9 is an inverted perspective view of the yarn-end engaging means of the take-up device;

FIG. 10 is an elevational view of another embodiment of yarn take-up device in accordance with the present invention; and

FIG. 11 is a sectional view, taken on the line 1111 of FIG. 10.

Referring to FIG. 1, the knitting machine head cornprises a needle cylinder 12 surrounding a dial plate 13, and operable to be fed with yarns by feed fingers 14, 15 and 16, respectively, operated identically in the conventional manner to selectively insert and withdraw yarns into and out of action. As shown in the drawings, the feed finger 14 has just inserted a yarn 20 into action in the needle circle 12, and the finger 15 has withdrawn a yarn 21 from action. Prior to the insertion of the yarn 20, the yarn was contained in a twisted, multi-yarn strand 2'3, passing from the inactive feed fingers across the dial plate 13, and up through the hollow spindle 24, as described more fully hereinafter. The spindle 24 is operated intermittently, -i.e. for several revolutions, upon each insertion and withdrawal of yarn to twist the strand 23, the twist tending to run back toward the inactive feed fingers. The strand passes under hold-down guide 26 against a post 27, over a selector guide 28, and under a deflector 29.

As shown in FIG. 2, the newly inserted yarn 20 is carried by the needle circle 12 across the dial plate '13, under the hold-down guide 26. Further travel of the needle circle peels the yarn from the twisted strand 23 and the selector guide 28 elevates the yarn 20 so that it passes into a hook 30 on the deflector 29. As shown in FIG. 2, the portion of the yarn 20 which is peeled from the twisted strand 23, is carried onto the elevated portion of the guide 28 before it passes the outermost portion of the deflector 29. The guide 28 therefore elevates the yarn 20 above the end of the deflector 29 so that it is engaged in the hook 30. The deflector 29 is resilient, and retains the yarn 20 under sufficient tension to be properly knitted into the fabric. In addition, the deflector serves to deflect the yarn 20 out of the path of the pick-up hook 36 mounted at the end of the spindle 24, as described more fully hereinafter.

As the needle circle travels, following the knitting in of the yarn 20, the yarn passes to the severing device 33, mounted closely adjacent to the needle circle 12 to sever the yarn and leave a tail which is sufliciently short to eliminate the necessity for subsequent trimming. In the present instance, the severing device 33 comprises an electro-thermal cutter, as shown in my application Ser. No. 653,368, filed April 17, 1957, and includes a holddown finger 34 which clamps the severed yarn end against the dial plate, as best shown in FIG. 5. The electro-thermal cutter is energized in timed relation with the operation of the feed fingers to be sufliciently hot to sever the yarn on contact when it reaches the severing device 33. Of course other severing devices may be employed if desired.

When the yarn 20 has been severed, the take-up de-I vice is operated to draw the twisted strand 23, including the severed strand 20, upwardly through the spindle 24, the drawing action releasing the yarn from the hold-down finger 34 and drawing it through the hook 30 of the deflector 29.

The yarn 21 is withdrawn from action shortly after the insertion of the yarn 20. The withdrawn yarn 21 is embodied in the fabric and passes over the dial plate to the inactive feed finger as the cylinder rotates. Rotation of the cylinder causes the yarn 21 to pass under the holddown guide 26, and further rotation causes the yarn 21 to pass under the deflector 29 by reason of the low terminal portion of the selector guide 28, as shown in FIG. 1. When the yarn 21 passes the outermost portion of the deflector 29, it overlies the selector guide 28 at a point where the guide is approximately coplanar with the dial plate, with the result that the yarn 21 is not elevated into the hook 30. When the cylinder 12 advances the yarn 21 into the severing device 33, the yarn 21 is drawn against the guide post 27, and a second guide post 35 adjacent the severing device 33 so that the yarn passes over the circular recess 31 in the dial plate which underlies the spindle 24, as indicated by the broken lines in FIG. 1. The severing device is operated to sever the yarn, and upon severence the spindle 24- is rotated.

In order to entrain the yarn 21 into the strand 23, the spindle 24 is provided at its lower extremity with a yam pick-up hook 36 which passes into the circular recess 31 and engages the yarn 21 upon rotation of the spindle 24, and wraps it about a twisted strand 23 to cause the severed strand 21 to be entrained in the strand 23. To prevent the yarn 21 from disengaging the spindle 24 and hook 36, a clamping action is provided by forming the hook 36 of resilient material, and uniting it to the spindle at a point spaced upwardly from the end thereof, as indicated at 37. Thus the yarn-engaging portion of the hook 36 may spring away from the spindle 24 and clamp the yarn between the spindle and the hook. This temporary clamping action insures wrapping of the yarn 21 about the twisted strand 23, and the subsequent withdrawal of the strand 23 through the spindle 24 draws the yarn-end 21 upwardly through the spindle, and incorporates it into the twisted strand. As shown in FIG. 9, the hook 36 is in a radial plane relative to the spindle, and by reason of the inclination of the spindle, the hook clears the yarn engaged in the hook of the deflector 29.

In accordance with the invention, the take-up means simultaneously twists the strand 23 and draws it upwardly through the hollow spindle 24. To this end the take-up means operates similarly to a double-twist spindle, and comprises a support bracket 41 mounting the spindle 24 for rotation therein, and also mounting a drive motor 42, which is operable to drive the spindle through a drive pinion 43 and a bevel gear 44. The spindle at its upper end has a fiyer head 45 mounted thereon for rotation with the spindle. Beyond the fiyer head 45 a flanged take-up cone 46 is rotatably supported on the upper terminal end of the spindle. The cone 46 is held against rotation by a guide bar 47 curving outwardly from the free end of the cone 46, and terminating at its free extremity in a collector 48. The guide bar cooperates with the collector to prevent rotation of the cone 46.

The strand 23 is passed upwardly through the hollow spindle 24, and is directed radially out of the bore of the spindle 24 by a guide roller 51 adjacent the axis of the spindle 24, and a second guide roller 52 spaced outwardly from the axis of the spindle 24 and in alignment with the flange 53 of the take-up cone 46. The strand is wrapped about the body 54 of the take-up cone, so that as the spindle rotates the strand 23 builds up on the body portion 54, thereby drawing the strand upwardly through the bore of the spindle 24, and simultaneously, the fiyer head twists the yarn, the twist tending to run back to the guide post 27 and hold-down guide 26. The body portion 54 of the take-up cone 46 tapers outwardly, so that as the strand 23 builds up on the cone the accumulated strand is forced axially outward on to the guide bar 47, and is free to fall into the collector 48 from which it may be removed during subsequent periods of inactivity. As noted above, the spindle is rotated only intermittently, i.e., for a short period after each yarn insertion or Withdrawal, so that the build-up of yarn in the collector 48 is small. Suitable electrical connections (not shown) are provided to operate the motor 42 in timed relation to the knitting machine, so that the motor operates to rotate the spindle 24 several turns after the inserted or withdrawn yarn is severed by the severing device 33. The advance of the twisted strand 23 up the bore of the spindle 24 takes up any slack which may occur in the inactive yarns, and imparts the necessary tension to these yarns, so that when they are put back into action the yarns operate properly.

A modified form of take-up means is shown in FIGS. 10 and 11. In this embodiment of the invention the spindle 24 is mounted on a frame 41 carrying a motor 42 which drives the spindle 24 similarly to the spindle 24. The spindle 24 carries the flyer head 45 and a take-up cone 46*, which are substantially identical to the head 45 and cone 46, described above. In place of the guide bar 47 and collector 48, a spring clamp 48 is mounted on the frame 41 and is biased in engagement with the tip of the cone 46 to hold it against rotation, and to retain the strand material which is built up there by the fiyer head 45 When the strand material accumulates sufficiently on the cone 46a, the spring clamp 48 is released and the material is removed. Following removal of the material, the free end of the strand from the fiyer head 45 is wrapped on itself about the cone 46 so that the material may build up on the cone during the subsequent operation of the knitting machine.

While particular embodiments of the present invention have been herein illustrated and described, it is not intended to limit the invention to such disclosure, but changes and modifications may be made therein and and thereto within the scope of the following claims.

I claim:

1. Yarn end control apparatus for a knitting machine having a dial, a needle circle surrounding said dial and a feed station having at least three feed fingers each carrying a yarn and being operable selectively between active and inactive positions respectively placing a yarn into the needle circle and taking a yarn out of the needle circle, said apparatus acornprising means guiding yarns from the feed fingers in the inactive position across the dial in a straight-line path to a point, and means to twist said yarns in said path into a twisted strand and to withdraw said strand from the dial to thereby advance and tension the yarns in said inactive fingers.

2. Yarn end control apparatus according to claim 1 wherein displacement of one of said feed fingers from inactive to active position inserts the associated yarn into the needle circle and causes it to span from said straightline path to said circle, at least one finger remaining in the inactive position to retain said twisted strand in its straightline path, said apparatus including severing means operable following said displacement to sever said span of yarn, said twisting and withdrawing means operable upon operation of said severing means to withdraw the severed yarn end with the twisted strand.

3. Apparatus according to claim 2 including means to tension and deflect said span of yarn prior to operation of said severing means.

4. Apparatus according to claim 2 wherein displacement of one of said feed fingers from active to inactive position takes the associated yarn from the needle circle and causes it to span from the needle circle to said feed finger in its inactive position, said guide means including means to dispose the latter span of yarn contig uous with said retained twisted strand, said severing means being operable to sever the latter span of yarn following said displacement of said latter feed finger to inactive position, said twisting and withdrawing means including wrapping means operable upon operation of said severing means to wrap the latter severed span about said retained twisted strand for removal upon operation of said twisting and withdrawing means.

5. Yarn end control apparatus for a knitting machine having a dial plate, a needle circle surrounding said dial plate and a feed station having a plurality of feed fingers with yarns therein, at least two fingers being in inactive position to elevate the yarns above the needle circle, a hollow spindle overlying said dial plate, a fiyer head mounted on said spindle, guide means to direct the yarns from said two feed fingers across said dial plate in a straight-line path to said spindle, throught said hollow spindle and to said flyer head, means to rotate said spindle and flyer head to thereby twist the yarns from said two feed fingers into a twisted strand in said straight-line path, and collector means cooperable with said spindle to withdraw said twisted strand from said dial plate through the spindle.

6. Apparatus according to claim including severing means on said dial plate intermediate said spindle and said needle circle operable to sever a newly-inserted yarn running from said twisted strand to said needle circle and through said circle to a feed finger in active position, and a newly-withdrawn yarn running from said needle circle to an inactive feed finger, said guide means including means to direct said newly withdrawn yarn into a path contiguous to said twisted strand, and means on said spindle to wrap the newly-withdrawn yarn in said contiguous path after its severance about said twisted strand whereby the latter strand carries the wrapped yarn through said spindle to said collector means.

-7. Apparatus according to claim 6 wherein said severing means is mounted on the edge of said dial plate adjacent said needle circle to sever the newly-inserted and newly-withdrawn yarns adjacent said needle circle.

8. Apparatus according to claim 6 wherein said wrap ping means comprises a hook on said spindle projecting from said spindle in a plane radial to said spindle and operable to engage and clamp the newly-withdrawn yarn in said contiguous path so that upon rotation of said spindle the hook wraps the newly-withdrawn yarn about the strand to incorporate the same into the strand.

9. Apparatus according to claim 8 including means defining a recess in said dial plate underlying said spindle, said spindle being mounted at an angle to said plate so that the hook passes into and out of said recess upon rotation thereof to thereby engage said newly-withdrawn yarn in the contiguous path.

10. Apparatus according to claim 9 including a defiector operable upon said newly-inserted yarn to deflect it out of the path of said hook.

11. Apparatus according to claim 10 wherein said means to rotate said spindle and flyer head comprises an intermittently operable motor operated upon actuation of said severing means.

12. Apparatus according to claim 5 wherein said collector means comprises a cone mounted against rotation in axial alignment with said spindle and cooperable with said fiyer head to engage the strand from said head and draw the same through said head and said spindle.

13. Apparatus according to claim 12 wherein said cone is mounted on said spindle for rotation relative thereto and includes means to immobilize the cone.

14. Apparatus according to claim 13 wherein said immobilizing means comprises an extension extending from the free end of said cone, said cone being tapered so that the strand engaged thereby is displaced from said cone onto said extension, said extension terminating in a collecting device receiving said displaced strand.

15. Apparatus according to claim 13 wherein said immobilizing means comprises a spring clip normally engag ing said cone to immobilize the same and displaceable therefrom to alford removal of the strand engaged there- 16. The method of controlling yarns in a circular knitting machine having a needle circle, a dial and at least two feed fingers at a feed station comprising the steps of passing a first yarn through one of said feed fingers and a second yarn through the other of said feed fingers, disposing both of said feed fingers in inactive position so as not to feed the first and second yarns to the needle circle at said station, and passing the first and second yarns from the feed fingers across the dial to a collector, thereafter shifting the feed finger containing said first yarn to active position to displace the first yarn passing through said feed finger into the needle circle to knit a portion of the same into the fabric produced by the machine, severing the portion of the inserted yarn which remains across the dial extending from the collector to the portion knit into the fabric, and twisting and withdrawing the severed portion of the first yarn and the second yarn toward said collector to form said yarns into a twisted strand for withdrawal to the collector, said twisting and withdrawing operation being initiated after severance of the first yarn and being terminated prior to subsequent withdrawal of said yarn from the needle circle.

17. The method of controlling yarns in a circular knitting machine having a needle circle, a dial and at least two feed fingers at a feed station comprising the steps of passing a first yarn through one of said feed fingers and a second yarn through the other of said feed fingers, disposing one of said feed fingers in inactive position so as not to feed the first yarn to the needle circle at said station, disposing the other of said feed fingers in active position to knit said second yarn into the fabric produced by the machine, and passing the first yarn from the inactive feed finger across the dial to a collector, thereafter shifting the active finger to inactive position to displace a portion of the second yarn passing through said feed finger from the circle, disposing said displaced portion contiguous to said first yarn, severing said displaced portion of the second yarn from the portion knit into the fabric, engaging and wrapping said severed portion of the second yarn about said first yarn, and twisting and withdrawing said first yarn toward said collector to incorporate therein said severed portion of the second yarn to form a twisted strand for withdrawal to the collector, said twisting and withdrawing operation being initiated after severance of the second yarn and being terminated prior to subsequent reinsertion of said yarn into said needle into said circle.

West June 29, 1909 Walker Feb. 10, 1914

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