US2422599A

US2422599A - Yarn take-up

Info

Publication number: US2422599A
Authority: US
Publication date: 1947-06-17
Anticipated expiration: 1964-06-17

Description

June 17, 5 S PIERRE I 2,422,599

YARN TAKE-UP Filed March 20, 1945 f/w/zwm:

Patented June 17, 1947 YARN TAKE-UP Eugene St. Pierre, Pawtucket, R. I., assignor to Hemphill Company, Central Falls, R. I., a corporation of Massachusetts Application March 20, 1945, Serial No. 583,721

8 Claims.

This invention relates to a new and useful improvement in yarn take-ups such as are used on knitting machines of the circular, independent needle type. Take-up mechanisms of the same general type are not new. One is disclosed in Patent #2,l93,311. The take-up of this invention is superior to those already known primarily in a control of the tension of the take-up spring which varies its effective tension and adapts the take-up to the exacting requirements of fine gauge knitting such as the knitting of sheer ladies stockings.

One form of the invention, designed for a circular, independent needle, knitting machine of the Banner type, is shown in the drawing of which:

Fig. 1 is a side elevation of a pair of take-ups and their controlling mechanism;

Fig. 2 is a plan View of similar scope; and

Fig. 3 is a view illustrating the free end of a take-up.

As many take-ups as desired may be used. They may be identical. Two are shown in the drawing, one in inoperative and one in operative position.

As shown in Fig. 1 the take-up consists of the usual light wire arm identical with the similar arm 2 of the other take-up, the free end of which is bent down and terminates in a yarn guiding loop similar to loop 3 of the other take-up and through which the yarn passes on its way from the cone to the yarn lever.

The other end of arm I is fixed in a block 4 pivoted on a horizontal shaft 5. In the form shown block 4 is slotted as at 5 so that the take-up arm 1 can be slid into it sideways after which it is fixed in position by set screw 1. Extending rearwardly of block 4 is a tail 8 which may be integral with arm i. This tail is offset laterally of arm l as best shown in Fig. 2. Below tail 8 is an arm 9 of substantially rectangular shape one end of which terminates in a loop I!!! through which tail 8 passes.

On the frame ll of the take-up is pivoted as at l2 a rocker I3, the other end M of which is adapted to be engaged and lifted by a cam [5 on a pattern drum l6. Intermediate the ends of rocker i3 is a clamp i1 consisting of a disc l8 and a screw l9 threaded into rocker [3. Arm 9 has a semi-circular bend 2!) at this point and terminates in a substantially circular loop 2! around pivot 12. In this way, an adjustment is provided for arm 9 since it can be moved vertically towards and away from screw I9 within the limits of clamp i1.

At the bend 22 of arm 9 is attached a spring 23, the other end of which is fastened to any suitable fixed part of the machine frame. Nor

maliy the downward pull of spring 23 causes arm 8 to urge arm I upward against the resistance of the yarn. In so doing loop In at the end of arm 9 slides along tail 8. In this way, the effectiv length of tail 8 with respect to shaft 5 upon which the take-up is pivoted is varied so that the tension exerted by the spring is also varied from what it would be were the spring attached directly to the take-up as has been customary in the past. By shaping tail 8 in a suitable manner, as best shown in Fig. 1, the efiect of spring 23 can be additionally adjusted. In former take-ups the spring had to be strong enough to lift the take-up arm quickly to its highest position, say degrees or more above the horizontal. As a result, when the take-up arm moved down the tension of the spring increased constantly and unavoidably became too great within the working range of the take-up while knitting is being carried on.

When knitting extremely sheer fabric such as a ladies stocking, very small errors in method, particularly those affecting the yarn, produce very noticeable fabric defects. It has been found that the tensioning effect of spring 23 upon take-up arm I should be substantially uniform throughout the movement of the take-up and, in some in stances, should be lighter when the take-up is down than when it is raised so that the take-up will exert a negligible or minimum effect upon the yarn during knitting.

Often it is desirable that the lifting effect of spring 23 upon arm I should increase as the arm rises in spite of the decreasing actual tension of the spring. All of these things can be accomplished by the hook-up described above through the proper shaping and proportioning of arm I, tail 8, arm 9 and spring 23. Since an infinite variety of conditions are met in the knitting of various fabrics these matters must and can be left for determination by those skilled in the art. The manner in which a take-up of this character operates is otherwise too well-known to require further description.

Whenever the take-up is to be made inoper tive it is accomplished by rotating drum is so that cam [5 will be lifted by it. This raises arm 9 and permits arm I to drop to a horizontal position. This is the position shownfor take-up arm 2, its arm 25 (the equivalent of arm 9) having been raised by lever 26 under the influence of cam 21 which is the equivalent of cam l5. The length of upwardly extending part 28 of arm 25 is such that when this arm is raised, as just described, the bottom of loop 29 at its end will press against the underside of tail 30 thus locking the takeup in its down position. The length of each earn and 2'! is such that the respective rocker will continue to ride upon it and the corresponding take-up remain locked until it is to function again. In other words, the length and position of each of these cams and the rate of rotation of drum it corresponds with the timing of the knitting operation with which they are concerned.

Associated with each take-up and operating thereby is a yarn clamp which opposes the feed ing of the yarn from the cone whenever the takeup rises beyond its normal range of operation during knitting. This consists of a pivoted arm 3 l, the front end of which constitutes an operating lever 32. The other end 33 of lever 35 is fixed to a similar end 34 of another lever, the other end 35 of which comprises one element of a yarn clamp. The other element of the clamp consists of a block 30, the upper end of Which is in exact alignment with the lower edge of clamp element 35.

Block 4 which carries the take-up arm i is also provided with an extension 37 adapted to engage the end of arm 32 and swing it downward. When this occurs part 35 of the yarn clamp is swung up and away from part 36 so that the clamp has no effect upon the feeding of the yarn. This is the situation shown with respect to the take-up represented by arm 2. Part 38 of its yarn clamp has been swung away from the other part by the engagement of end 39 of block 60 with the end of arm 4!, the equivalent of arm 32.

The clamp is closed when the take-up arm 1 reaches the position indicated in dotted line at 12 which is somewhat higher than its normal upper most position while knitting is going on. Thus the yarn is free to be fed from the cone to the needles during knitting but will be clamped so that it cannot be fed from the cone whenever the take-up rises appreciably higher; The connection between ends 33 and 34 of the lever which operate each yarn clamp is'by means of a screw or bolt 43 passing through elongated slots. Consequently, the position of part 35 of the clamp in relation to arm 33 can be varied so as to insure that the clamp operates efiiciently and at the desired position of the take-up arm.

Part 33 of the yarn clamp is also mounted upon its support 44 so that it can be adjusted verticall and. fixed at its correct position by a screw 45.

The entire take-up and its operating drum can be mounted in any desirable way. Here its bracket H is shown attached to the upright 46 which supports the bobbin stand and other parts of the upper part of the machine. Drum I 5 may be operated by any suitable mechanismunder the control of a pattern drum or any other suitable timing device.

I claim:

1. A yarn take-up for a knitting machine which includes an arm, one end of which is supported by a horizontal pivot so that it is swingable in a vertical plane, an extension of said arm, a lever associated therewith for swinging said arm upwardly and means associated with said lever for energizing said lever.

2. A yarn take-up for a knitting machine which includes an arm, one end of which is supported by a horizontal pivot so that it is swingable in a vertical plane, an extension of said arm, a lever associated therewith for swinging said arm upwardly and resilient means associated with said lever for energizing said lever.

3. A yarn take-up for a knitting machine which includes an arm, one end of which is supported by a horizontal pivot so that it is swingabl in a vertical plane, an extension of said arm, a lever associated therewith for swinging said arm upwardly, resilient means associated with said lever for energizing said lever and means for looking said arm in its lowermost position.

4. A yarn take-up for a knitting machine which includes an arm, one end of which is supported by a horizontal pivot so that it is swingable in a vertical plane, an extension of said arm, means associated therewith for swinging said arm upwardly, resilient means associated with said last mentioned means for energizing said last mentioned means and means for isolating said arm from said resilient means.

5. A yarn take-up for a knitting machine which includes a vertically swingable take-up arm having an extension, mean for swinging said arm upwardly which consists of a source of energy which is greatest when the arm is down and which decreases progressively as the arm rises and a lever associated with said source of energy and said extension for applying the decerasing energy of said source to said arm so that its raising power with respect to said arm increases progressively as its inherent energy decreases.

6. A yarn take-up for a knitting machine which includes a vertically swingable take-up arm having an extension, resilient means for swinging said arm upwardly which consists of a source of energy which is greatest when the arm is down and which decreases progressively as the arm rises and a lever operatively interposed between said extension and said resilient means for applying the decreasing energy of said source to said arm so that its raising power with respect to said arm increases progressively as its inherent energy decreases.

' 7. A yarn take-up for a knitting machine which includes a vertically swingable take-up arm having an extension, a tension spring for raising said arm, the inherent energy of said spring being greatest when said arm is down and progressively decreasing as said arm rises and a lever operatively connected to said spring and said extension for causing the raising power of said" spring to increase with respect to said arm as its inherent energy decreases.

8. A yarn take-up for a knitting machine accordingto claim 5 which also includes means operable by the knitting machinefor isolating said arm from said swinging means at any desired time.

EUGENE ST. PIERRE.

REFERENCES CETED llhe following references are of record in the file of this patent:

UNITED STATES PATENTS