US2227355A

US2227355A - Feeding apparatus

Info

Publication number: US2227355A
Application number: US197749A
Authority: US
Inventors: Robert H Lawson
Original assignee: Scott and Williams Inc
Current assignee: Scott and Williams Inc
Priority date: 1938-03-23
Filing date: 1938-03-23
Publication date: 1940-12-31
Anticipated expiration: 1957-12-31

Description

Dec. 31, 1940. R, H LAWSON 2,227,355

FEEDING APPARATUS Filed Narn 23, 193s sheets-sheet 1 Iwveror ROBE/3T H. LAWSON Dec. 3l, 1940. R. H. I AwsoN FEEDING APPARATUS Filed March 25, 1938 4 Sheets-Sheet 2 gg I 1706715014 EOBEET H. LAweo/v @owwy Dec. 31, 1940. R, H AwsoN 2,227,355

FEEDING APPARATUS Filed March 25, 1958 4 Sheets-Sheet 3 n lumai/Mor Fo ET H. LAwso/v 4 Sheets-Sheet 4 R. H.- LAWSON FEEDING APPARATUS Filed March 25, 1938 www Dec. 31, 1940.

Patented Dec. 3l, 1940 UNITED STATES PATENT OFFICE Scott 8a Williams, Inc., Laconia, N. H

ration of Massachusetts a corpo- Application March 23,1938, Serial No. 197,749

5 Claims.

This invention relates to feeding apparatus.

It is a primary object of the invention to provide apparatus for positively feeding material under substantially uniform tension irrespective of the nature of the material or of the speed at which it is moved. The tension desired may be almost negligible or may be considerable depending upon the kind of material being fed and what happens to it beyond the apparatus of this invention. The normal speed of travel of the material may be either constant or variable, in either event it is a feature of the invention to positively feed the material at a speed determined by the demand for it.

The principles of the invention are herein disclosed in their particular application to the feeding of yarn, but this is merely illustrative and not limiting. In one embodiment shown the yarn being fed is representative of rather delicate and practically unstretchable material which can be subjected to only ,a very light tension. In another illustrative example the yarn being fed is representative of strong and greatly stretchable material which can be fed at a comparatively high tension. These embodiments, as before stated, are to be taken as merely illustrative of the best mode in which I have contemplated applying the principles of my invention for it is intended that the patent shall cover by suitable expression in the appended claims whatever features of patentable novelty exist in the invention as a whole.l

In the accompanying drawings:

Figure 1 is a front elevation of apparatus embodying my invention particularly adapted to the feeding of small delicate yarn;

Figure 2 is a side elevation, looking from the right toward Figure 1;

Figure 3 is a diagrammatic showing of a simple electric circuit employed in my apparatus;

Figure 4 is a plan taken partly in section as on line 4-4 of Figure 1;

Figure 5 is an elevation partly in section as on line 5 5 of Figure 4; l

Figure 6 is a sectional elevation taken as on r line 6-8 of Figure 4;

the elements shown in Figure 9:

Figure 11 is a front elevation, similar to Figure 1, showing an added feature;

Figure 121s a front elevation, similar to Figure 1, showing a feature which may be employed to take up slack in the yarn;

Figure 13 is a side elevation of parts of Figure l2;

Figure 14 is a iront elevation showing the adaptation of the invention for feeding strong and greatly stretchable rubber yarn at high 10 tension;

Figure 15 is an enlarged front elevation of certain details of Figure 14;

Figure 16 is a plan view of the details of Figure 15;

Figure 17 is a sectional elevation taken as on line l'l--ll oi.' Figure 15;

Figure 18 is a side elevation of other details of Figure 14; and

Figure 19 is a rear elevation of the details of Figure 18.

Referring now to the drawings and particularly to Figures 1 to 8 inclusive, the apparatus shown in these figures is especially applicable to the feeding of rather delicate material which should be subjected to but very light tension, for example the yarn which might be used in a knitting machine. Such yarn A is illustrated as coming from any convenient source of supply (not shown) and passing through a guide 20, then between

feed gears

22, 24 and thence through the ring end 26 of a rather long light element 26, whence the yarn passes along to the machine by which it is processed. The

feed gears

22, 24 are driven by an electric motor 28 mounted on a bracket 30 secured to any convenient support 32 such as a part of the frame of the machine using the yarn. As shown, the gear 24 is secured to the shaft of the motor and is driven directly. The other gear 22 is mounted on a shaft 34 carried by an arm 36 which is adjustable on the bracket 30 by virtue of a pivot pin 38, slot 40, and clamp bolt 42. As shown in Figure 1, the adjustment of the arm 36 and the gear 22 is for a thin yarn A, while in Figure 8, the adjustment of the same parts is for a comparatively thick yarn A.

The current for the electric motor 28 is supplied thereto from any convenient source by way of a rheostat 44 shown mounted on a depending L-shaped arm 46 which in turn i: rigidly supyported by distance sleeves 48 and bolts Sli to a straight arm 52 extending downward from bracket 30. This L-shaped arm 46 is made of nonconductive material such as Bakelite or the like and at the end of its horizontal portion 46a (see u arm 52 on which is secured by clamp screw 54 a` strip of resilient metal 65 which is a good conductor of electricity. One end 55a of this strip is hooked around the exposed end 55m ofthe axle and the other end 55h is curved and extended over the rods 58 so as to rest on only one of them at a time. This yoke arm 52 also carries the element 25. previously mentioned, which terminates in the ring end 25 that engages the material being fed. To the axle 55 is secured a wire 58 leading from a source of Aelectrical supply. circuit for the motor can now be readily traced, being shown diagrammatically in Figure 3. From the source of electric current the lead wire 55 connects with the axle 55. passes by way of the resilient strip 55 to one of the bars 58, thence by its connecting Wire 50 to the rheostat 44 and thence by wire 18 to the motor. From the motor another wire 12 connects with the source of supply.

'I'he speed of the motor lis controlled by the amount of current reaching it from the rheostat 44 and the effectiveness of the rheostat is determined bythe contact between the end 55h of the resilient strip 55 with one of the rods 58. As shown in Figure 5, the strip is in contact with the fourth rod 58, starting from the right and counting in an anti-clockwise direction. This contact means a certain speed of the motor depending upon the effect imposed by the rheostat. If the brush enclv 55h moves counterclockwise to make successive contacts with each successive rod 58, the motor will speed up, as each contact in a counterclockwise direction means a greater supvply of current to the motor. If the brush end 55h reaches the endmost rod 58 in its countericlockwise movement, the circuit is fully opened to the motor by way of the wire 14 which bypasses, as it were, the rheostat 44. Reversely,

` movement of the brush end 55h in a-clockwise direction reduces the speed of the motor as each successive rod 58 is contacted. In the drawings,

the particular'rheostat 44 shown has only ive stages, but this is to be understood as representative of a rheostat havingas many stages as there are rods 58 on the hub 45, except that the last rod 58a on the right-hand end of the series has no electrical connection whatever with the rheostat ormotor. Although I have particularly disclosed and described a rheostat as the means for effecting a change in thespeed of the motor, this is to be understood as merely illustrative of suitable means for varying the motor speed.

This last rod 58a is so located that when itis in contact with the end 65h` of the resilient strip, the yoke arm 52 and elementl 25 will be in the position PI indicated in dotted outline in Figure 5. When this position is reached, the circuit to the motor is broken and in the embodiment of the invention shown in Figures 1', 2, 'l and 11, a brake is applied 'to the gear 22 to check the motor.

This is accomplished by a lever 15, pivoted. on the The current then/ fected by a link connecting its outer end to the yoke arm 52.- When the latter is in its dotted position P, the leverwlll engage the gear 22, as indicated in Figure 7, and quickly stop the motor.

When feedingmaterial on which a Very light tension is to be imposed, the combined weight of `the element 25, yoke arm 52, resilient strip 55,

link 80, and lever 15 are relied upon to impose such tension. These respective parts rotate very easily, are all very light and their total weight is not large, but even if this should impose a larger tension than desired, a light counterweight 82' may be provided on the yoke 52 as indicated in dotted outline in Figure 4. Conversely, if a greater tension is desired than the weight of the moving parts mentioned will afford, a suitable weight may be added or a spring arranged to exert a pull on the yoke arm 52 in a clockwise direction. Normally, the tension and speed of the yarn will hold the element 25 substantially at the fullline position shown in Figure l. If the machine using the yarn should slow up momentarily, the length of yarn between the feed gears 22, 24

and the machine would momentarily increase, but` this would immediately allow element 25 to swing downward and thereby move the brush end 55h of the resilient strip to a different rod 58 and reduce the speed of the -motor correspondingly. Likewise if the demand for yarn increases, the

.element 25 is swung upward and the motor promptly swing downward to the dotted position PI, open the circuit to the motor 28; and apply the brake 15 to gear22. Upon the machine being again started the pull on the yarn will raise element 25, release the brake 15, and again establish the circuit through the motor so that the latter will again drive the gears to positively feed the yarn at the proper speed as determined by the demand. Incase the yarn between the

gears

22, 24 and the Amachine should break, the element 25 will drop immediately to the dot-anddash line position P2 shown in Figures 1 and 5. As it passes the dotted position PI, the circuit t0 the motor will be broken and the brake applied to the gear 22. Just before reaching the dot-anddash position P2, the yoke arm 52 strikes a rod 84 and pushes it to the left to open a stop motion switch 85 associatedl with the main power circuit to the machine. This will cause the latter to stop and a similar stoppage will occur if the supply is allowed to run out and the end of the yarn passes out from between the feed gears.

In Figures 9 and 10 there are shown grooved rolls 22' and 24' in place of the feed gears 22 and 24 of the apparatus hereinbefore described.

These are particularly suited to the feeding of u 'thm rubber yarn A" which is subject to a iight tension. A modified arm 55' is mounted on the .bracket 30, and grooved pulleys 88 and 90 are provided on the shafts of the feed rolls so that the upper feed roll 22' may be driven by a rubber tension because the resilient force of the yarn, upon the circuit to the motor being broken, will impose sufficient -resistance to the turning of the feed rolls to promptly stop the motor.

Figure 11 discloses an added feature particularly useful when the material is being fed to a machine which when starting demands immediately that the yarn assume its full normal speed of travel.l Such rapid acceleration of the yarn from rest to full normal speed would swing the element 26 almost instantly from its lower position, corresponding lto no movement of the yarn, to its uppermost position P3, shown in dot-anddash outline in Figure 11. Even though this would by-pass the rheostat and connect the circuit direct to the motor, there would nevertheless be a momentary lag of the feed gears while the motor is getting up to speed. To avoid breakage of the light yarn, a pivoted rod 94 is provided on bracket 30, having a short arm 94a engaged by a light coiled spring 96 whose Strength is sufficient during ordinary feeding of the yarn to maintain the rod 94 in the full line position shown. In the event of the sudden acceleration of the yarn just described, the force of this spring is temporarily overcome and rod 94 may be swung to some such position as P4 shown in dot-anddash outline. This will occur following the movement of element 26 to the position P3. The swing of lever 94 makes available for immediate travel a portion of the yarn between the feed gears 22, 24 and the machine, and this added portion, as it were, enables the motor to get up to speed before a breaking tension is imposed on the yarn. As the motor speeds up, rod 94 returns promptly to its full line position and element 26 then swings downward until the normal speed of the motor is restored corresponding to the normal demand of the yarn.

Figures 12 and 13 show a. simple attachment which may be employed with light material in lieu of a braking device for the motor. An arm 91 is mounted on the previously described arm 36 Vand this new arm has an arcuate portion 91a on which is secured a wire 98 to form an elongated slot |00 close by a portion of the path traveled by the ring end 26 of the element 26. On the latter is added a ring 02 of rather large diameter, so that when the element 26 is in its normal working range, as shown in full lines in Figures 12 and 13, the yarn A will extend from the feed gears 22, 24 directly through the ring |02 and slot |00 to the ring end 26. Thus in normal movement of the yarn the ring |02 and slot |00 play no part. But if the machine stops and there is no longer any demand by the machine for the yarn, the element 26 falls down- 4ward as previously described to effect breaking of the circuit to motor 28. Since now there is no brake applied to the motor, its momentum will cause a slight overtravel after its supply of current is cut off. This causes a corresponding feeding of the yarn by the feed rolls and in the absence of the ring |02 and slot |00 might cause the yarn to snarl and twist on itself. However, as the element 26 svn'ngs downward, the yarn reaches the bottom end of slot |00 and is there engaged by the wire 98. At about the same time the yarn is also engaged by the ring |02. Accordingly a new loop, of a sort, is established in the yarn extending from the ring |02 to the wire 98 and -thence to the ring end 26', clearly shown in heavy dot-and-dash lines in Figure 12. This readily takes up the yarn fed by the overtravel of the motor and keeps the yarn from snarling or twisting on itself.

Thus far the invention has been described in its application to the feeding of rather delicate material which can be subjected to only a very light tension. It is within the scope of the invention, however, to feed heavier material under a relatively high tension. One such application of my invention is the feeding of rubber yarn such as is commonly used in the make-up of a golf ball center. a very considerable tension, in the neighborhood of two pounds, and this amount of tension must be maintained throughout the complete winding of the center. When the latter is started, it is small in diameter but as the winding proceeds the center grows larger. The center may be rotated at a uniform speed of rotation in which case the linear speed at its surface increases as theI center grows larger. Or the center may be turned by a moving surface which may move at a uniform or an accelerated velocity. When this surface moves at uniform speed the surface speed of the center remains constant since it is rotated by contact with a-uniformly moving surface. When the velocity of the moving surface is accelerated as the center grows larger then the surface speed of the center increases and the speed of the yarn being fed to the center is an accelerated one. The adaptation of my invention to this specific problem is disclosed in Figures 14-19 inclusive, but this disclosure is to be taken as illustrative of the application of the invention generally to feeding heavy material under considerable tension and at a variable speed.

In the application shown, the machine |014 for winding the golf ball center C is shown on a support such as the bench |06. The golf ball center is made by winding the rubber yarn on a small spherical core (not shown). This core with a convolution or two of the rubber yarn around it is placed on a belt |08 which is driven by the mechanism of the winding machine |04. This mechanism moves the belt |08 at an accelerated speed as the center of the golf ball grows larger. A,springhe'ld arm ||0 with a suitable roll ||2 holds the core and the wound-on yarn rmly in contact with the belt |08. Mounted on the topof the winding machine is a spool ||4 of the rubber yarn to be wound. The yarn is fed from the spool through a guide I6 to between a series of pairs of novel feed gears, I8, |20, thence downward around a roll |22 at the end of a relatively long lever |24, and then upward around a guide roll |26 to the center.

Such yarn must be fed under downward to swing the bell-crank |34 and apply a braking force by way of the strap |30 to the brake drum |28 of the motor.

Beyond the brake drum onl the motor shaft is 'secured a driving gear |48 lwhich meshes with another gear |50 mounted cn a sub-shaft |52. Beyond these gears, on-each shaft, are the novel feeding gears |18, |28 for the rubber yarn. Each feed gear (see Figure 17) is in essence a deeply grooved pulley preferably made in two parts. Each tapered surface of each part is provided with teeth which partly ntermesh when the two parts of the gear are brought together. The yarn passes through the guide ||6, thence nearly around the feed gear H8 and then partly around the other feed gear |20. As it sinks in between the internieshing teeth of the feed gears it is rmly grasped thereby and positively fed.

From the feed gears the yarn goes to and partly around the roll |22 on the lever |24. This lever is secured to a short shaft |60 suitably journaled on a standard |06a on the bench. (See Figure 19.)

` and a drum |64. A strap |66 attached tot the drum extends downward to a spring |68, the other end of which is suitably anchored. By selecting a spring of proper strength, any desired tension may be imposed on the yarn, since the spring tends to swing the lever |24 downward against the resistance offered by the por-tion or the yarn which is between the feed gears H8, |20 and the center C.

The gear |62 on the lever shaft |60 mesnes,

with a much smaller pinion |10 mounted on a shaft |12 of insulating material which extends through a bracket journal |14 on the standard |06a. On the left end of this shaft |12, as seen in Figure 18, is secured the yoke arm 62, hereinbefore described. On the axle 56, (coaxially arranged with the shaft |12) is the insulated hub 46carrying the bars 58, connected as before described (but not so shown in Figures 18 and 19) to the rheostat 44. The resilient brush strip 66 is mounted on the yoke arm 62 as before, and proper wires lead from the rheostat to the motor. Thus it is that as` lever |24 swings and rotates gear |62, the pinion |10 and yoke arm 62 are rotated to cause the brush strip 66 to contact with different bars 58 and thus vary the current supply to the motor and thereby alter its speed.

Should the yarn break, or for any reason should the winding machine stop,lthe lever |24 swings downward and, by virtue of the gears |62 and |10, yokej 62 and strip 60, breaks the circuit to the motor. At the same time the downwardly moving lever |24 engages the washer |46 and through spring |44 pulls the rod |40 downward and applies the brake to the motor thus stopping it promptly.

As the center of the ball grows larger, the speed of travel of the yarn becomes greater. This causes lever |24 to swing upward and thus increases the speed of the motor and the feed of the yarn. While this upward swing of the lever does to some extent increase the pull on spring |68, it does not materially alter the tension on the yarn, because the moment arm of the spring with respect to the fulcrum is so short, that the slight increased tension in the spring is negligible. Accordingly, it follows that regardless of the speed of the yarn, the tension imposed upon it is substantially uniform throughout the entire winding of the center.

I claim: 1. Feeding apparatus for feeding material un- Onthis shaft is also secured` a gear |62 der substantially uniform tension comprising geared elements positively engaging the material to draw it from a' source of supply and to feed it; means for driving said elements comprising a variable speed electric motor; means creating a demand for said'material; control means for altering the speed of said driving means including an element engaged by .the material and moved-thereby rotatably about an axis in accordance with the demand therefor, a series of contact wires distributed about said axis and individually connected to a rheostat, there being a contact brush carried by said element and rotatable therewith to make contact with only one of said contact wires at a time whereby the power input to said motor is varied according to the movements of said element to vary the speed of said Adriving means and braking means for said feeding apparatus controlled by the material and arranged to interlock with a geared element.

2. Feeding apparatus for. feeding material under substantially uniform tension comprising eleer input to said motor, a rotatable element en- I gaging the material and rotated thereby as the demand for said material varies and means rotatable by and with said element to vary the effective resistance imposed by said rheostat thereby to vary the speed of the said driving means,

a slotted guide for the material along which said rotatable element moves and means on said rotatable element cooperating with said guide only upon rotation of said element beyond a predetermined position for increasing the slack of the material held by said rotatable element.

3. Feeding apparatus for feeding material under substantially uniform tension comprising means creating a demand for said material; geared feeding elements capable of positively engaging the material to draw it from its source of supply and to feed it; an electric motor driving said elements; a rheostat controlling the current supply to said motor and thereby its speed; means including a. pivoted element engaged by Ithe material and moved thereby in accordance with variations in the demand for the material; and means associated with said element `close by its axis of rotation and affected by the movements of said element to cause a change in the eiect of said rheostat to vary the speed of said motor in accordance with said demand and thereby maintain a substantially uniform tension in the'material and braking means for said feeding apparatus controlled by the material and arranged to engage a tooth of a geared element.

4. Feeding apparatus for feeding material under substantially uniform tension to a machine which demands Ithe material, comprising geared feeding means positively engaging the material between its source of supply and its entry into the machine; a variable speed motor for driving said feeding means; braking means for said feeding apparatus controlled by the material and arranged to interlock with a geared element and control means including an element engaging the material between the feeding means and machine and adapted to be actuated by variation in the demand for said material to effect a corresponding variation in the speed of said driving means whereby the speed of travel of the material is adjusted to maintain substantially uniform tension in the material being fed, there being a series of separate electrical conduits having terminals distributed about the axis of rotation of said element and means moved by the rotation of said element to establish connection between one of said series of conduits and a source of electrical supply, and means associated with said series of conduits for changing the power input to said motor in accordance with the particular circuit established by rotation of said element.

5. Feeding apparatus for feeding material under substantially uniform tension while supplying a variable demand comprising feeding means having rotating surfaces positively engaging the material to feed it; a variable speed motor connected to said feeding means to rotate the said surfaces; means for varying the current input to said motor to thereby vary its speed including an element pivoted on an axis and having a re1- atively long feeler arm arranged so that its end engages the material and is rotated thereby in accordance with changes in the demand of said material, and a series of separate conduits having an end of each terminating close by the axis of rotation of said feeler element and means actuated by the rotation of said element to establish connection between one of said ends and a source of electrical power, the effective power input to said motor being determined by the connection thus established thereby causing the motor to vary its speed and the speed of the feeding means to supply the material in accordance with the variable demand, a slotted guide for the material along which said pivoted element moves and means on said pivoted element cooperating with said guide only upon pivoting of said element beyond a predetermined position for increasing the slack held by said pivoted element. ROBERT H. LAWSON.