US2340889A - Apparatus for feeding warp thread to knitting machines - Google Patents

Description

- 1944- F. .KLUMPP ETAL 2,340,889

APPARATUS FOR FEEDING WARP THREAD TO KNITTING MACHINES I Filed Dec. 50, 1942 4 Sheets-Sheet 1 271 29 30 3/ 35 I 26 33 I "1 1 I I T I25 26a 24a. 22 23 22 a: 2 w 38a. 23 25 38 1: 2 1? 42 40 is Z/ O v O INVENTORS F: a .1 lfLl/M P gala: kuy gz a tifb F 1944- F. KLUMFP ETAL I APPARATUS FOR FEEDING WARP THREAD TO KNITTING MACHINES Filed Dec. 30, 1942 4 Sheets-Sheet 2 I mll llll] IIHI "um" INVENTO S r [all I f C/lsrle; H; al-VI Z ATTORNEYIY,

Feb. 8, UM ETAL APPARATUS FOR FEEDING WARP THREAD TO KNITTING MACHINES Filed Dec. 30, 1942 4 SheetS-Shegt 3 ,1 C1. 4-

Charles 1?. caLw/v Ai :ORN EY Feb. 8, 1944.

APPARATUS FOR FEEDING WARE THREAD T0 F. KLUMPP ETAL Filed Dec. 30, 1942 KNITTING MACHINES 4' Sheets-Sheet 4 INVENTORS:

Ferd trzand Khan o muse; 4 B) Bessz Klumpp, EAElUrR/X, II f Char! (alvin A TTORNEY.

Patented yet. a, 1944 APPARATUS FOR FEEDING WARP 7 TO KNITTING MACHINES rnnnan" Ferdinand Klumpp, deceased, late of Union City, v

N. J., by Bessie Klumpp, N. 1., and Charles H. Colvin, assignors to Robert Relner,

executrix, Union City, Morrlstown, N. 1., Inc., Weehawkcn,

Application December 30. 1942, Sam No. 410,540 In Great Britain February 5, 1942 This application is a continuation in part of our patent application Serial #278,392, filed on June 10, 1939, for an apparatus for feeding filler thread to a knitting machine.

The invention relates to textile machines, and more particularly to an apparatus for feeding thread to a knitting machine.

One object of the invention is to provide an apparatus by means of which threads of any kind, for example elastic threads or non-elastic threads, may be fed to a-knitting machine under a substantially constant tension.

Another object of the invention is to provide an apparatus, by means ofwhich threads of any kind may be fed to the knitting instrumentalities of a knitting machine in such a manner that the threads are in a proper predetermined condition of tautness as they are formed into a fabric.

A further object of the invention is to provide warp feeding mechanisms for a knitting machine of the type generally referred to as a warp knitting machine which are practical and efllcient in operation and which are automatically responsive to a condition of the warp.

Other objects and advantages of the invention will be pointed out in the detailed description thereof which follows or will be apparent from such description.

In order to carry out the invention in practice we provide an apparatus for feeding warp thread to a knitting machine comprising, in combination, a beam, means including an electric motor for driving said'beam, means for tensioning the thread as it is fed from said beam, and means responsive to a variation in the tension of said thread for affecting the operative condition of said electric motor.

In order that the invention may be readily understood and its practical advantages fully appreciated reference may be had to the accompanying drawings wherein a convenient form of apparatus for feeding threads to a warp knitting machine is shown. However, it will be understood that the invention is susceptible of embodiment in other forms of construction than that shown and that the feeding apparatus according to the invention may be used for the feeding of threads to textile machines or the like other than warp knitting machines, for example straight bar knitting machines or circular knitting machines.

In the drawings is:

Fig. 1 an elevation, partly in section, of a warp knitting machine having warp and filler feed- 13 Claims.

ing mechanisms according to the invention associated therewith, a portion of the warp knitting machine being broken away,

Fig. 2 a fragmentary top plan view of the warp feeding mechanism,

Fig. 3 a fragmentary front elevation of the warp feeding mechanism,

Fig. 4 a fragmentary elevation of the filler feeding mechanism,

Fig. 5 a fragmentary elevation of a portion of the warp feeding mechanism illustrating a mercury switch controlled by a balanced member of the mechanism,

Fig. 6 a fragmentary elevation, partly in section taken on line 6-6 of Fig. 7, of a portion of a different embodiment of the warp feeding mechanism illustrating photo-electrical control means controlled by a balanced member of the mechanism, and

Fig. 7 is a sectional view of the detail shown in Fig. 6, taken on line 1-1 of Fig. 6.

Flat knitting machines, for example, warp knitting machines, in many instances employ warp beams on which are wound a desired number of warp threads or ends which are drawn from the beam as they are knitted into fabric by the needles of the machine. As these threads are knitted, the beam revolves, and in most instances it is necessary to provide some sort of a beam brake to prevent the beam from running free and permitting a loose or slack condition of the warp thread at the knitting needles. Various types of friction brakes have been devised for preventing free rotation of the beams, but have met with indifferent success because they are inherently incapable of permitting rotation of the beam at the time and in the amount required. If the friction device has a suflicient braking action on the beam to prevent the beam from over-running because of its momentum, the pull of the warp threads necessary to turn the beam initially against the friction of the brake places the threads under greater tension than is usually desired, this being particularly so in the case of highly elastic yarns such as certain worsted yarns and lastex yarns.

In the case of elastic threads, such as lastex yarns, it is practically impossible with friction brakes to control the feed of the yam' in such a way that it is under a substantially constant tension. This lack of control often results in a fabric of uneven texture with promiscuously scalloped edges. In the case of loosely spun yarns, such as 7 line gauge loosely spun worsted yarns of slight tensile strength, a friction brake device for controlling mm mum is practically useless and sometimes harmful. Furthermore, the weight'of the beam is often so substantial that the force to overcome its inertia is greater than the coijhbinedqtensilestrength f the threads which'pull the beam, with the result that the threads part; This condition is particularly evident in the manufacture of narrow fabrics where the total warp ends are relatively few'in relation to the size and weight of the beam.- Still other types of warp threads such as, for exainple,

asbestos, have practically no-tensile strength at all and cannot properly be formed into a fabric unless they are slack at the needles. It will be apparent that under such conditions a friction brake for the beam would actually be disadvantageous and a freer mining beam would not solve inflexibility of the metal. In some cases a cer-,

tain amount of slack is required in the metal warp threads where certain types of metal cloth are being made. Either condition of the metal thread is difllcult, if not impossible to obtain with the conventional frictionally restrained beam.

Often the above-noted fabrics, in addition to others, require the incorporation therein of filler threads. Here again it is desired to control accurately the tension of such threads as they are corporated into the fabric, regardless of the texture of the threads or their tensile strength. In so far as we havebeen able to determine, there has been no satisfactory solution of the problems encountered in properly tensioning such filler threads as desired in different types and kinds of fabrics. Often but a single strand is incorporated as a filler, and where the thread being used has but slight tensile strength, it is clear that the forces exerted on the thread by the pull of the machine must be accommodated or counteracted in order to avoid breakage. Where an'elastic filler is being incorporated into the fabric, it is often desirable to maintain the tension of the thread at a predetermined, constant value, and for the reason pointed out hereinabove, conventional friction brakes devices are unsatisfactory.

It is accordingly another object of this invention to obviate the above mentioned difllculties, and to provide warp and filler feeding mechanism which solves the several problems referred to in a thoroughly efficient and practical manner.

Referring now to Fig. 1 of the drawings, a warp knitting machine is generally indicated at I 0, and this machine may be similar to that shown in the U. S. Patent #2',247,092, Knitting machine, issued to Ferdinand Klumpp and Fritz Lambach on June 24, 1941. Machine III, which corresponds generally to that type of knitting machine generally referred to as a warp knitting machine, comprises suitable frames I l and I2 rising from a base It which with the frame supports the operating -mechanism of the machine substantially as described in detail in the aforementioned U. S.'Patent #2,24'l,092. Machine III also includes knitting instrumentalities which in general comprise one or more needle banks, a plurality of longituaaaaaaa dinally arranged sinkers l3 and cooperating sets of loopers l3. Needles l4, sinkers l5, and loopers I3 coact upon operation of the machine to knit thread or yarn supplied thereto into a fabric which, if desired, may have incorporated therein a filler through the operation of a carrier or filler laying mechanism II. If desired, a complete deuprights 20 and 2|.

scription of these several instrumentalities may be found in the above noted U. S. Patent Frames II and I2 support a suitable number of arms l8 and I! which in turn support posts or These posts have mounted thereon suitable hangers or brackets 22 disposed at opposite ends of the machine and between which supporting tubes 23 extend. Any suitable number of supporting tubes 23 may be provided, but for illustrative purposes the drawings show a pair at the left hand side or front of the machine. as viewed in Fig. 1, and a pair at the rear of the machine. Tubes 23 therefore comprise suitable supports for pairs of notched bars 24 and 25, these bars being located at opposite ends of the machine to provide suitable beam supports.

The yarn or thread knitted in-a knitting machine of the type under consideration is usually wound in suitable lengths on a beam, and as the yarn is knitted into fabric by the machine, it is drawn from the beam effecting rotation thereof. Such a beam (see the top of Fig. l) is indicated at 26 and is supported on upper beam supports 24, being maintained against displacement by notches 24a in upper supports 24. Beam 26 has a suitable supply of warp yarn or thread W. As noted hereinabove, conventional beam rotation controls usually take the form of a friction brake or the like which prevents free running of the beam. As noted, however, there are many disadvantages to this type of beam control, and to the preclusion thereof the mechanism now to be described has been provided for.

As shown in Fig. 1, the upper left hand tube support 23 has mounted thereon a discoid 21, the upper portion 21a of which (see Figs. 2 and 3) carries an electric motor 28. The upper end of the motor housing has attached thereto a casing 29 which contains suitable speed reduction gears comprising a self-locking worm meshing with a worm gear. Said speed reduction gears are connected to a pinion 30 which meshes with a gear 3| (Figs. 1 and 2) mounted on the axle or spindle 26a of beam 26. Operation of motor 28, as will be described in detail hereinafter, thus effects rotation of beam 26 through the action of gears 30 and 3|, but because of the speed reduction afforded by the gears in housing 29, beam 26 is rotated at suitably slow speed.

As shown in Figs. 2 and 3, a pair of brackets 33 and 34 are suitably mounted on upper tubular support 23, and as is more clearly shown in Fig. 1, the upper surfaces of these brackets are inclined with respect to the horizontal, and are provided with a series of notches 33a and 34a (Fig. 3) respectively. A drum or roller 35 is suitably supported on a spindle 36, and the opposite ends of the spindle are carried in corresponding notches 33a and 34a of supports 33 and 34.

suitably pivoted to the hangers and adapted to adjustably receive respectively frame bars 4| and 42, the left hand ends of which, as viewed in Fig. 2, are connected by a rod 43 or the like. The opposite ends of bars 4| and 42 are also connected by a rod 44, and between rods 48 and 44 we provide a tension bar or roller 45, the oppo-- site ends of which are supported or iournalled in rods 4| and 42 (see Fig. 3). As shown in Figs. 1 and 2, rod 44 carries a depending weight 48, the mass of which may be varied in accordance with the tension desired to be imparted to warp W as will be described below.

Referring to the upper left hand portion of Fig. 1, the warp threads W are taken from beam 28, led beneath tension bar 45, passed over roller 38 and thence trained downwardly across a guide 41 suitably secured to machine II and finally through loopers It to needles l4. It may now be seen that by reason of the warp threads W passing under tension roller 45 frame bars 4| and 42 together with tension roller 45, rod 44 and weight 48 comprise a balance member having opposed forces acting thereon, i. e., the upward pull of warp threads W and the downward force exerted by weight 48. It will also be clear that the force exerted by weight 48, and hence the tension on warp threads W, may be varied as desired either by varying the distance between tension roller 45 and pivot blocks 38 and 40, or by varying weight 48.

As best shown in Fig. 5, motor 28 is connected in circuit with a mercury switch 48, which is supported in a cradle 48 mounted on the upper end- 31a of the hanger 31. Cradle 48 includes a downwardly extending arm 50 from which extends a stud which is received in a fork 52 secured to the end of a rod 53, the lower end of rod 53 being fixed to pivot Brook 33 (see Fig. 3). As rod 53 is related to frame bars 4| and 42 at the pivotal axis thereof, slight angular movement of the bars effects substantial angular displacement of fork 52. Thus, as viewed in Fig. 5, clockwise movement of rod 53 and fork 52 causes counter-clockwise movement of switch 48 causing the mercury therein to flow away from switch contacts 48a and 48b to break the circuit to motor 28. Similarly, counter-clockwise movement of rod 53 causes clockwise movement of mercury switch 48 to close the circuit to the motor.

From the above it will now be clear that as warp threads W (Fig. 1) are drawn into machine It by the action of the knitting instrumentalities therein, the threads pull against tension roller 45 to cause counter-clockwise movement of frame bars 4| and 42. As hereinbefore noted, this effects clockwise movement of mercury switch 48 to energize motor 28. Energization of the motor causes rotation of beam 28, and thus warp thread is positively fed by the beam, which'preeludes an increase in thread tension. Feeding of the warp thread, however, by motor 28, eases the pull of the warp threads and thus permits tension roller 45 and the associated frame bars 4| and 42 to drop, 1. e., the frame bars move clockwise. This effects counter-clockwise movement of mercury switch 48, which breaks the circuit to motor 28 and feeding of warp by beam 25 ceases. creases in the tension of the warp thread W, beam 28 is operated or its rotation is stopped, and in effect the tension of the warp threads is maintained at a constant uniform value for the following reasons: The warp threads W are maintained under tension by the weight 48 acting on Thus, for but slight increases or dethe frame bars or levers 4| and 42. The angle of rotation of the levers 4| and 42 about the pivots of the pivot blocks 88 and 48 between their lower end position and their upper end position for controlling the mercury switch 48 is extremely small (it has been found in practice that the stroke of the weight is as low as 15 or less), so

that the moment of torsion caused by the action of the weight 48 on the levers 4i and 42 remains the same for all positions of said levers. A constant moment of torsion in turn result in a constant tension of the warp threads W during the feeding thereof.

Furthermore, it may be mentioned that the self-locking worm of the speed reduction gears enclosed in the casing 28 and connected to the beam 28 by the Bears 88 and 8| serves to lock the beam when the beam is not driven b the motor 28, so that the tensioning means 4| to 48 remains in the position shown in Fig. 1 when the beam is not driven. In other words, the warp beam drive comprising the motor 28, the speed reduction ears including the self-locking worm in the housing 28, the pinion 88 and-the gear 3| acts as a positive brake against rotation of the beam when not driving the beam.

While the drawings illustrate but one warp beam and but a single control thereof, it will be obvious that a plurality of beams and controls may be used to supply as many sets of warp threads as are desired up to practical limitations. It will also be clear from the above that regardless of the type of warp threads being used, its tension or lack of tension can be readily and closely controlled so that in the case of elastic warp threads, such threads can be knitted while under tension so as to result in an elastic fabric.

Where warp threads of little or no tensile.

strength are being knitted, there is no danger of the threads being torn by reason of the pull exerted thereon by the knitting action, as the threads can be positively fed through the action of motor 28, as described. Similarly, where a metal cloth is being manufactured, and it is desired to maintain the metal warp threads under high tension, this substantial tension can readily be maintained by the control herein described, where it would be difllcult if not impossible to do so with a conventional friction beam brake.

As hereinbefore noted, it is often desirable to incorporate a filler thread or threads into the fabrics as it is being knitted. To this end, we have provided the filler feed mechanism generally indicated at 54 (left hand side of Fig. 1). Filler feed mechanism 54 comprises a standard or support 55 which carries a lower platform 58 and an upper support 51. shown in Fig. 4, a spindle 58 has its inner end rotatably mounted in platform 51, the spindle extending from the platform so as to support a spool 59 of filler thread F. Spindle 58 also carn'es a spur gear which meshes with a gear 8|, adapted to be driven by a motor 82 through a speed reduction mechanism including a worm meshing with a worm gear arranged within the casing 53. Preferably, the worm is of the selflocking type. Thus, as gears 6| and 58 are operated by the motor, spool 59 is rotated at a suitable rate of speed to unwind filler thread F therefrom, and, on the other hand, the filler spool drive comprising the motor 52, the speed reduction gears including the self-locking worm in the housing 83, the pinion 58 and the gear 8| acts as a positive brake against rotation of the spool when not driving the spool.

As is more clearly.

Filler thread-F is led through an eye 04 carricd by arm 85 suitably secured to support 55, and from this eye it is passed through another eye 66 secured to the top of a weighted shutter 61. Shutter 61 is provided with guide arms 68 which embrace vertical guide posts 69 and 09a (Fig. 1) which constrain the weighted shutter to movement in a vertical plane, as will be described.

Platform 56 includes an extension 50a on which a source of light 10 is mounted. Lighting device 10 is arranged and adapted to cast a beam B of light in the direction of a photoelectric cell II, which is connected in a conventional manner to a suitable switch generally indicated at I2, switch I2, in turn, being connected to motor 62 to effect energization and deenergization thereof as the beam B falls on photocell 'II, or is cut off there from by shutter 61.

It will thus appear that weighted shutter 61 is the controlling factor of the feed of filler thread F.

From eye 66 on weighted shutter 61 filler thread F is led through another eye I3 in arms 65 (Fig, l) and from this eye the filler thread leads to I suitable eyes on carrier H, which reciprocates, as

described in the above mentioned U. S. Patent #2247092, to lay the filler in the fabric as it is knitted. As the carrier I'I reciprocates, it draws filler thread F into machine I with the result that weighted shutter 61, which hangs on a loop of the filler, is pulled upwardly along guide rods 69 and 69a. However, as soon as the shutter rises sufficiently so that beam B from light source I0 can fall on photocell II, motor 63 is energized to cause rotation of filler spool 50. This effects a positive feed of filler thread F, and therefore there is no tension created on the filler by the reciprocation of carrier II other than that resulting from the weight of weighted shutter 61. If but little tension is desired in filler thread F, the weight of shutter 6'! may be adjusted accordingly. If substantial tension in the filler thread is desired, it is obvious that the attainment thereof is readily effected by increasing the weight of the shutter. In any event, the value of the tension under which filler thread F is drawn into the machine is maintained substantially constant, which assures an evenly textured fabric free from a ruiiied or scalloped effect. It will be clear that this condition will obtain regardless of the nature of the filler thread, and it also will appear that by reason of the positive feed of filler thread, a thread of very low tensile strength may be used without risk of the threads parting,

Thus, the above described mechanisms provide for an automatic feed for both warp and filler threads of such a nature that regardless of the kind of thread or arn being used, the tension under which it is being fabricated may be maintained at a predetermined constant value with the result that an evenly textured fabric is readily attainable. Furthermore, by reason of the positive feed effected by the warp and filler feed devices, warp and filler threads of extremely low tensile strength may be fabricated to form a fabric of a fineness heretoforeunattainable in a machine of this character. As substantial flexibility of adjustment is afforded by the controls according to the invention, elastic yarns may be readily fabricated to form fabrics of substantially any desired elasticity up to the elastic limits of the threads employed.

According to the provision of the above described apparatus, the various objects hereinbefore described are attained in a thoroughly practical and efficient manner.

The photoelectric control means I0--'I2,controlled by the shutter 61 of the filler feeding mechanism may be replaced by any other suitable control means such as a mercury switch or any other switch which, in turn, is controlled by a suitable controlling member substituted for the shutter 61.

Likewise, the controlling mercury switch 48 of the warp feeding mechanism controlled bythe balanced member 4I-46 may be replaced by any other suitable control means, for example by photo-electrical means. Figs. 6 and 7 illustrate an embodiment of our invention according to which such photo-electrical control means are used in the warp feeding mechanism. Said Figs. 6 and 7 show some parts corresponding to parts shown in Fig. 5, and similar reference numerals are usedto indicate such corresponding parts. The swingable loaded member or frame bar 4| engaged with the pivot block 39 is pivotally mounted on the lower end of the hanger 31 at I00. The hanger3'I adjustably embracing the bar has an enlarged head IN. A bracket generally indicated by I02 is secured to the hanger 31 by means of screws I03 or the like. The upper end of rod 53 fixed to the block 39 has a fork 52 in engagement with a stud I04 mounted on a control member or plate I05 swingably arranged on the head IOI of the hanger 31 at I06. The movable control member I05 passes through a slot I01 of the bracket I02. If the loaded frame bar '4I is in the position shown in Fig. 6, the swingable plate I05 is in such a position that it is in the path of the light rays emanating from a source I08 of light mounted on top of the bracket I02, so that the light rays cannot reach the photo-electric cell I09 mounted on the bracket I02 and electrically connected with the motor coupled with the warp beam; in this position of the movable parts of the warp feeding mechanism, the motor is not energized. If, however, owing to a change in the tension of the warp threads, the frame bar M and rod 53 are moved in counter-clockwise direction as viewed in Fig. 6, the control plate I05 is swung in clockwise direction out of the path of the light rays, so that the latter reach the photo-electric cell I09 and cause an energization of the motor for driving the warp beam, until, upon'a clockwise movement of the loaded frame bar M and rod 31, the control plate I05 is again moved into the path of light rays for interrupting same and causing a stoppage of the motor.

As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth, or shown in the accompanying drawings is to ,be .interpreted as illustrative and not in a limiting sense.

What we claim is:

1. An apparatus for feeding warp thread to a knitting machine comprising, in combination, a beam, means including an electric motor for driving said beam, means for tensioning the thread as it is fed from said beam, and means responsive to a variation in the tension of said thread for affecting the operative condition of said electric motor.

2. An apparatus for feeding warp thread to a knitting machine comprising, in combination, a beam, an electromotor for rotating said beam to feed thread therefrom, means for maintaining the thread under tension, and electrical means controlled by said tensioning means for altering the operative condition of said electromotor in response to a variation in the thread tension.

3. An apparatus for feeding warp thread to a knitting machine comprising, in combination, a beam, an electromotor for rotating said beam to feed thread therefrom, means for maintaining the thread under tension, and electrical means including a controlling switch in circuit with said electromotor and operatively connected with said tensioning means for altering the operative condiiton of said electromotor in response to a variation in the thread tension.

4. An apparatus for feeding warp thread to a knitting machine comprising, in combination, a beam, an electromotor for rotating said beam to feed therad therefrom, means for maintaining the thread under tension, and. electrical means including photo-electric means in circuit with said electromotor and controlled by said tensioning means for altering the operative condition of said electromotor in response to a variation in the thread tension.

5. An apparatus for feeding warp thread to a knitting machine comprising, in combination, a beam, an electromotor for rotating said beam to feed thread therefrom, means for locking the beam when not driven by said electromotor, means for maintaining the thread under tension, and means responsive to a variation in the thread tension for affecting the operative condition of said electromotor.

6. An apparatus for feeding Warp thread to a knitting machine comprising, in combination, a beam, an electromotor for rotating said beam to feed thread therefrom, means for locking the beam when not driven by said electromotor, means for maintaining the thread under tension, and electrical means controlled by said tensioning means for altering the operative condition of said electromotor in response to a variation in the thread tension.

7. An apparatus for feeding warp thread to a knitting machine comprising, in combination, a beam, an electromotor for rotating said beam to feed thread therefrom, means for locking the beam when not driven by said electromotor, means for maintaining the thread under tension, and electrical means including a controlling switch in circuit with said electromotor and operatively connected with said tensioning means for altering the operative condition of said electromotor in response to a variation in the thread tension.

8. An apparatus for feeding warp thread to a knitting machine comprising, in combination, a beam, an electromotor for rotating said beam to feed thread therefrom, means for locking the beam when not driven by said electromotor, means for maintaining the thread under tension, and electrical means including photo-electrical means in circuit with said electromotor and controlled by said tensioning means for altering the operative condition of said electromotor in response to a variation in the thread tension.

9. A warp feeding mechanism for knitting machines or the like comprising, in combination, a beam, an electromotor for rotating said beam to feed warp thread therefrom, a-balanced member for maintaining the warp thread under tension, and a controlling switch in circuit with said electromotor and operatively associated with said balanced member. said switch being adapted to alter the operative condition of said electromtor upon the creation of an unbalanced condition of said balanced member by a change in the value of the tension of the warp thread.

10. A warp feeding mechanism for knitting machines or the like comprising, in combination, a beam, an electromotor for rotating said beam to feed warp thread therefrom, means for locking the beam when not driven by said electromotor, a swingable loaded member for maintaining the warp thread under tension, and a controlling switch in circuit with said electromotor and operatively associated with said swingable loaded member, said switch being adapted to alter the operative condition of said electromotor upon a change in the position of said swingable loaded member by a change in the value of the tension of the warp thread.

11. A warp feeding mechanism for knitting machines or the like comprising, in combination, a beam, on electromotor for rotating said beam to feed warp thread therefrom, speed reduction gears incluomg a self-locking worm arranged between said beam and said electromotor whereby said beam is locked when not driven by said electromotor, a swingable loaded member for maintaining the warp thread under tension, and a controlling switch in circuit with said electromotor and operatively associated with said swingable loaded member, said switch being adapted to alter the operative condition of said electromotor upon a, change in the position of said swingabie loaded member by a change in the value of the tension of the warp thread.

12. A warp feeding mechanism for knitting machines or the like compris' in combination, a beam, an electromotor for rotating said beam to feed warp thread therefrom, means for locking the beam when not driven by said electromotor, a swingable loaded member for maintaining the warp thread under tension, photo-electhe means including a light source and a light sensitive cell in circuit withv said electromotor, and a, movable control member operatively connected with said swingable loaded member for control of the passage of light between said light source and said light sensitive cell, said light sensitive cell being adapted to alter the operative condition of said electromotor upon a change in the position of said control member by a change in the value of the tension of the warp thread.

13. A warp feeding mechanism for knitting machines or the like comprising, in combination, a beam, an electromotor for rotating said beam to feed warp thread therefrom, speed reduction gears including a self-locking worm arranged between said beam and said electromotor whereby said beam is locked when not driven by said electromotor, a swingable loaded member for maintaining the warp thread under tension, photo-electric means including a light source and a lightsensitive cell in circuit with said electromotor, and a movable control member operatively connected with said swingable loaded member for control of the passage of light between said light source and said light sensitive cell, said light sensitive cell being adapted to alter the operative condition of said electromotor upon a. change in the position of said control member by a change in the value of the tension of the warp thread.

- BESSIE KLUMPP, Executm: of the Estate I Ferdinand Klumpp,

Deceased.

CHARLES H. COLVIN.

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