US2709553A

US2709553A - Method of wire coiling

Info

Publication number: US2709553A
Application number: US242733A
Authority: US
Inventors: Hubert E Wellcome
Original assignee: FLORENCE K WELLCOME
Current assignee: FLORENCE K WELLCOME
Priority date: 1951-08-20
Filing date: 1951-08-20
Publication date: 1955-05-31
Anticipated expiration: 1972-05-31

Description

W 1955 H. E. WELLCOME METHOD OF WIRE comma 2 sheeiswsheet 1 Filed Aug. 20, 1951 FIG. 3

IIIII INVENTOR. HUBERT E. WELLCOME ATTORNEY zfmwsa May 33, W55 H. E. WELLCOME METHOD OF" WIRE COILING 2 Sheets-Sheet 2 Filed Aug. 20, l951 FIG.

hill/11 Ill/W III// II FIG. -6

INVENTQR HUBERT E. WELLCOME 3 Va ATTORNEY United States Patent Ofiice 2,709,553 Patented May 31, 1955 METHOD OF WIRE COILING Hubert E. Wellcome, Fairfield, Conn, assignor to Florence K. Wellcome, Pleasantville, N. Y.

Application August 20, 1951, Serial No. 242,733 2 Claims. (Cl. 242-54) This application is a continuation-in-part of application Serial No. 630,528, filed November 23, 1945, now abandoned.

This invention relates to wire coils and to methods of and machines for making them, and particularly relates to coils of wire from which the wire may be drawn at high delivery speed without rotation of the delivered wire relative to the coil and without development of stress in the delivered wire.

The delivery of soft fiber lines such as hempen and similar rope, is readily obtained since the soft fiber line can be flaked down to pay out readily or wound in a criss-cross pattern to run out without twisting to any extent that gives excessive difficulty. There is no factor of elasticity which offers trouble in such soft fiber lines. But with wire and metal cable, difiiculties arise since they cannot be coiled in any way which produces sharp turns or bends in the wire or cable because this would set the wire or cable. In addition, the elasticity of the metal makes it necessary to provide a coil in which the tendency of the wire to straighten out does not cause the line to snarl at the coil. These considerations are particularly important when the Wire or cable is to be delivered at relatively high speeds such as in excess of one hundred feet per second, or what may be called projectile speeds, as in the paying out of life lines in sea rescue, and in military activities of various types as for example in operations carried out from moving airplanes.

In prior art devices, the problems were never solved. The wire or cable was delivered at very slow speeds, substantially below one hundred feet per second, and frequently there was snarling and kinking also resulting in the Wire or cable snapping and resultant failure of the operation. Special types of winding convolutions and coiling operations did not eliminate the difiiculties.

Among the objects of the present invention is a wire coil which may be unwound as rapidly as feasible with outbodily rotation of the coil.

Other objects include such wire coils in which rapid delivery of the wire at high speed is possible without difiiculty.

Further objects include such wire coils in which the wire leaves the coil in untwisted, relaxed condition.

Additional objects include methods and machines for making such wire coils and their utilization.

Still further objects and advantages of the present invention will appear from the more detailed description set forth below, it being understood that this more detailed description is given by way of illustration and explanation only, and not by way of limitation, since various changes therein may be made by those skilled in the art without departing from the scope and spirit of the present invention.

In connection with that more detailed description, there is shown in the accompanying drawing, in

Figure l, a front elevation, partly in section, of one form of wire coil produced in accordance with the present invention, in

Figure 2, an enlarged fragmentary view illustrating the uncoiling wire and forces operative thereon; in

Figure 3, a plan view of one form of machine that may be utilized in producing the articles of the present invention and carrying out the methods thereof; in

Figure 4, a mandrel ready for the application of wire thereto, partly in section, with fragments of wire in place for illustrative purposes; in

Figure 5 a section of a means for holding the wire in position; and in Figure 6, a front elevation, partly in section, of a modification of the present invention.

In accordance with the present invention a coil of wire or metallic cable is produced adapted to deliver the wire by Withdrawal therefrom even at high delivery speed without rotation of the delivered wire relative to the coil and without development of torsional stress in the delivered wire, the latter leaving the coil in untwisted relaxed condition. These results are made possible even at delivery speeds of one hundred feet a second and as high as is obtainable with present day projection as for example 900 to 1000 feet per second, by utilization of the wire in coil form under conditions of stress that upon delivery exactly neutralize any stress that would normally arise in paying out such wire or cable if not compensated. For these purposes, the coil is a close, substantially cylindrical spiral of helically wound wire (or cable), of elastic metal, supported between spaced rigid end flanges that confine the coil. The end flanges are maintained in spaced relation in contact with the ends of the coil in any desired way.

The wire in the coil is in a state of elastic deformation, the angle of said torsional deformation being substantially the same for each convolution of the coil. It is essential that such deformation be within the elastic limit of the material of the wire. Consequently the wire must be metallic and of metal with a sufiiciently high elastic limit for the particular purposes in hand. It may be noted, however, that if a wire is of a material that can be formed into a circle of the desired diameter (i. e. of the smallest convolution of the desired coil) without taking a permanent set, it has been empirically determined that the material is satisfactory for the purpose intended. V

The coil of wire under elastic torsional deformation is adapted to deliver the wire very rapidly in unkinked and unstressed condition. The wire does not take any permanent set in the coiled condition, and is free from kinks or twists in the relaxed condition. Thus, the coil of wire under torsional deformation in the coiled condition restrained by the end flanges presents a live wound coil which maybe instantaneously converted into the straightened relaxed wire; the delivery of the wire from the coil taking place at startling speeds of from 900 to 1000 feet per second.

One method for determination of utility of any particular material for a specific article may be made in accordance with the formulation given below which will indicate the minimum coil diameter which may be used, namely:

E X at where D is the diameter of the smallest convolution of the coil, E is Youngs modulus, d is the diameter of the individual wire (whether single or stranded, laid or cabled into a larger diameter wire line), and S is the tensile strength of the material within its elastic limit.v

In theory, this equation relates to closely wound coils, but modification for coils with a spacing of ten wire diameters (which is about as widely as they are wound), is relatively slight. By taking S at a good safe value (which must be done in any event because of variation in any ordinary material), no difficulty is experienced in properly coiling the wire without endangering the operation due to permanent set.

From these considerations it can be seen that steel sufficiently work-hardened or tempered is very suitable, since E is high, but S is very high. A material such as bronze wire, with E half that of steel, has however a value of S which may be one-third to one-fifth that of steel. Accordingly, bronze wire may be used to make articles under the present invention but for a given individual wire diameter (d a coil from bronze wire would require a larger diameter D than one from steel wire.

In actual practice, given a sample of wire desired to be coiled, it is feasible merely to form the wire successively into circles of varying diameter, noting the diameter at which the wire does not straighten out. The coil diameter should then be larger than the diameter of the circle which did not straighten out.

The angle oi the torsional deformation is substantially the same for each convolution of the coil, and desirably is made equal to one turn per convolution opposite in direction to the direction of unwinding of the wire as viewed from the end of the coil from which the wire is drawn. The term wire is used herein as intended to cover any metallic line whether wire or cable, and whether of single or multiple strand, etc.

Where the line is paid out from the inner periphery of the coil, the coil may be placed within a rigid casing that is substantially cylindrical and is in direct contact with the outer peripheral layer of the coil, the casing being attached to the flanges to hold them in spaced relation. One of the flanges may be provided with an opening through which the wire is delivered. Where the line is delivered from the outer periphery of the coil, the coil is retained on the rigid mandrel on which it was initially wound, the mandrel carrying the end flanges attached thereto, and the flanges being in direct contact with the ends of the wire coil.

The term substantially cylindrical is used herein since it is not essential to have the coil exactly cylindrical. in fact it is preferable to have the coil taper slightly from end to end, for example about 4. In such case the mandrel on which the winding of the coil is carried out may be given the desired taper. The main purpose of the taper is to permit withdrawal of the mandrel when desired. An included angle of 2 may be used, but withdrawal of the mandrel may be more ditficult than desired. Also the outer casing when used, will taper in the same way in order to maintain its contiguity with the outer layer of the coil. The end flanges may be set at right angles to the mandrel, or may taper either inwardly or outwardly. In the case of a coil which is withdrawn from the interior periphery, an outward flare, that is, one in which the outside layer of wire is longer than those in the center, should not be so great as to lead to kinking of the wire as it is withdrawn. It will be uiiderstood that in the case of a coil dispensed from the exterior periphery of the coil, the flare may be considerable. This dishing of the flanges serves the purpose, among others, of making them rigid, especially if they are of thin material. The number of layers in the coil may be as desired.

Referring to the article as illustrated in Figure l of the drawing, the body it) of the coil of wire is retained within the torus-shaped end flanges 11., 11 which are in direct contact with the ends of the body of the coil. Each flange carries an opening 12 through one of which the wire may be withdrawn for delivery from the inner periphery of the coil. In the illustrated form, the wire is withdrawn through the opening in flange 11. At this point it might be noted that after the coil is formed, it is necessary to draw the line through the proper flange, otherwise a severe twist will be imparted to the line upon withdrawal. The end flanges 11, 11 are maintained in spaced relation by rigid casing 13 in direct contact with the outer periphery of the coil body it The casing may carry these flanges 11, 11' in any desired way as for example by providing the casing 13 with an inturned flange or bead 14 at one end, and an outwardly turned flange 14 on the other end, to match with corresponding parts on the peripheries of the end flanges. The casing can be assembled on the completed coil by slipping over the beaded flange and bolting to the other flange, so that the casing and end flanges will mutually support each other in desired position. The article as shown in Figure l is provided with a taper, the coil of wire and casing both showing such taper in equal amount.

it is desirable to provide means to assure that the wire remain in position before it is intended to be with drawn. One desirable expedient that may be used for this purpose is illustrated in Figure l, and in section, in rotated position, in Figure 5. The flange and mandrel have been omitted from Figure 5 for the purposes of clarity, although it is to be understood that of course the relation of wire to bushing does not exist except in conjunction with the flanges. As shown, it may take the form of a thin tear-out bushing B, of any desired material such as soft aluminum or the like, shaped to conform closely with the inner periphery of the coil of wire it It is thus substantially cylindrical in shape, in the form of a collar, as shown at 44, having its outer peripheral edge 45 flared to lie contiguous to the end convolution of the wire at that point. The bushing has an opening 46 through which the pulling end of the wire passes. The opening 46 may be a hole, but is preferably simply a notch or slot in the edge of the bushing. When the wire is withdrawn, it bears against the aluminum, the latter tears and distorts and passes out of the casing, releasing the wire for ready withdrawal. If the preferred notch in the edge of the bushing is utilized, the bushing is free of the line once it is distorted and collapsed, no tearing being necessary which would be required to free the wire of the bushing if a hole were used.

In the enlarged fragmentary View shown in Figure 2, a dot-dash line 15 ,is shown on the wire leaving the coil 10. In the uncoiled portion 16 of the wire, the line 15 is parallel to the axis of the wire, and may be considered an element of its cylindrical surface in the normal, relaxed condition of the wire there being no torsional strain. However, in the body 10 of the coil, the line 15 is shown as extending helically with respect to the axis of the wire, thus representing the twist or torsional strain in which the wire is coiled. While the direction of this twist is represented in the drawing, it can most readily be described as follow: looking at that end of the coil 10 from which the wire is withdrawn, and looking along the wire coming from the coil, the coil (Figure 2) appears to unwind clockwise, while the twist, as the point of observation advances along the wire, is counterclockwise. This is true both when the wire is being taken from a layer wound as shown or from an adjacent layer where the winding is from the opposite end. Quan' titatively, the twist is equal to approximately one turn per convolution of the wire in the coil. This amount of twist presupposes a closely wound helix of comparatively large diameter, compared to the diameter of the line. This is the usual case with steel rope or wire, as the minimum diameter of coil is fixed by the ability of the rope to bend without taking a permanent set.

The degree of twist is dependent on the diameter of the coil, the diameter of the wire, the pitch of the convolution, i. e. how closely wound the helix is, and on the metal of the wire. All these factors must be taken into account in producing a coil in which the wire has not been converted into a condition of permanent set. The latter must be avoided, and accounts for the failure of the prior art to eliminate the difficulties. In general, the riecessary condition is satisfied by specifying that the torsional deformation is within the elastic limit of the wire.

While as illustrated, the coil convolutions may be wound close, that is, with adjacent convolutions touching, the convolutions need not touch but may be spaced from one another for example as much as tenwire diameters between turns in random winding.

Articles as disclosed herein may be made in any desired way as for example by the machine shown in Figure 3, which is illustrative.

The mandrel 20, having a portion tapered to produce the taper evident in Figure l, is supported in

bearings

21 and 22 for rotation. Hearing 21 is removable, to permit the flanges 11, 11' to be placed thereon, and the withdrawal of the completed coil. In order to rigidly support the flanges, which may be of sheet material as shown,

collars

50 and 51 may be provided aflixed to the mandrel 20, and against which the flanges 11, 11' engage. Collar 50 must, of course, be removable, in order to permit the withdrawal of the mandrel, the collar 51 may also be removable if desired. The mandrel is driven by the bevel gears 23, which in turn are driven by shaft 24. Shaft 24 may be driven by a belt 25 or any other suitable drive. In order to assure even spooling of the wire on the mandrel, the distributor mechanism 26 is provided, which consists of a conventional double threaded screw and traveler provided with limit stops reversing the direction of motion of the traveler, as is well known in the art. The distributor screw is driven by

gears

27 and 28 from the mandrel shaft, thus assuring a definite distributing motion for every revolution of the mandrel.

When a bushing B is used as explained above, the mandrel may be provided with a slight shoulder 47 as shown in Fig. 4, the depth of which is equal to the thickness of the metal of the bushing B so that the latter will be flush with the mandrel surface on which the wire is coiled. In the event that the standing end of the coil is secured to another, similar, coil, it is desirable to have the standing end pass through the center opening of the flange opposite to the flange through which the wire is withdrawn. To this end, the flange 11 is provided with a projecting or upstruck spiral, in which the standing end may be inserted. When this is done, it is of course necessary for the mandrel to be grooved, as shown at 48 (Fig. 4), to permit withdrawal of the completed coil without shearing oil the wire. Of course, a notch in the flange could be provided, to obviate the necessity of a groove in the mandrel, but this may sometimes result in a tendency of the wire from the adjacent dispenser to bind as it runs out of its dispenser.

In order to produce the twist referred to, the supply reel 29 is mounted in such a fashion as to rotate about an axis parallel to the line of the wire. The reel is mounted on a shaft 30, which is held by separable bearings 31 to the flier frame 32. This frame is mounted to rotate in bearings 33, and is driven by the chain 34 which engages sprocket 35 fixed to the shaft 36 and sprocket 37 on shaft 24. The two sprockets have been shown the same size, as are bevel gears 23, which is one way of achieving the required one twist per revolution of the mandrel 20.

The shaft 38 of the flier 32 has a bore 39 through which the wire passes to the mandrel. It is desirable to provide the guide wheels 40 which help to transmit the twist to the wire being paid otf from the supply reel 29. These wheels may be rotatably mounted on the hollow shaft 38.

A suitable brake mechanism (not shown) may be applied to the supply reel or its supporting shaft to impart the desired tension to the wire being wound on the mandrel.

The article thus made includes the coil mounted on a rigid mandrel 20 between

rigid end flanges

11, 11. This article is removed from the

bearings

21 and 22 and the casing such as 13 in Figure l is applied before the mandrel 20 is removed. When the casing 13 is in position, the mandrel. 20 is removed giving the finished article as shown in Figure 1.

In order to make the entire winding and withdrawal of the mandrel entirely clear, reference is bad to Figure 4. The flanges I1, 11 and the bushing B, as well as the collar 51 being in position on the mandrel, the wire end (which is to be the pulling end of the wire) is passed through the opening 46 of the bushing, through a slot 42 in the mandrel 20, and wrapped around the mandrel at the reduced region 54. This is a mere matter of convenience, and any other means may be utilized to provide the necessary end for pulling. The collar or flange 50 is then placed on the mandrel, and pinches the right hand flange 11 against the end of the tapered portion of the mandrel. The assembly is mounted in the

bearings

20 and 21, and the machine is started. No real stress is exerted on either

flange

11 or 11, and it is therefore unnecessary to provide anysupport except for the

collars

50, 51. Collar 51 may be grooved at 52 to provide clearance for the struck-out spiral referred to before.

After the machine has run suificiently to bring the level of the wire in the coil to the proper height it is stopped, and the wire cut and threaded into the struck-out spiral in flange 11'. It will issue from a slot 53 in the collar 51, and is drawn out to make the last turn on the outer periphery of the coil flush with the others. The outer casing 13 is slipped in place, and bolted or riveted to the flange 11. If desired, the bead 14 may be clinched for greater rigidity of the casing.

The end collar 50 is then removed, and the mandrel 20 withdrawn. The slot 48, which of course must register with the point of exit of the wire from the struck-up spiral, permits such withdrawal of the mandrel 20 without shearing the standing end of the completed coil.

To exemplify articles produced in accordance with the present invention, 576 feet of 93 7 x 7 aircraft cable may be formed into a solenoidal coil having an internal diameter of 6 /2, an outside diameter of 8%", and a length of 8%", the convolutions in the coil being contiguous to one another. The angle of the torsional defor mation was equal to one turn per convolution of the coil. The wire may be of steel.

A modified form of spool is shown in Figure 6 adapted for use on machines for taking back-twisted wire from a stationary spool to deliver torsion free wire to a fabricating machine. In this case the wire coil 10 is wound on the spool barrel having

end flanges

71, 72 attached thereto. The mounting mandrel 73 carries a corrugated rubber layer 73 bonded to the mandrel '73 and wedged between the barrel 70 and mandrel 73 so that a unitary structure is obtained. Mandrel 73 is provided on its inner end with an annular lip 74 enabling the mandrel to be attached to wall plate 75 on wall 76. A stop 77 bolted to wall 76 is shown at the upper portion of the inner flange 71, against which the flange engages. A conventional rotating flier (not shown) is used to remove wire from the spool. The spool may be wound in this case as described above for other modification, with as many convolutions of back twisted wire as desired. For securing the end of the wire after coiling, cellulose tape has been found suificient.

In both types of articles produced in accordance with the present invention, there is no rotation of the delivered wire relative to the coil, the wire is delivered in unstrained, relaxed condition, high speed of delivery such as from to 1000 feet/ second is possible, without kink, snap or other difliculty.

Having thus set forth my invention, I claim:

1. The method of making a coil of wire adapted to deliver said wire by withdrawal therefrom at high delivery speed without rotation of the delivered wire relative to the coil and without development of torsional stress in the delivered wire, said method comprising winding wire of elastic metal on a rigid mandrel between rigid end flanges carried on said mandrel, rotating said mandrel to wind the wire thereon in a close substantially cylindrical helical coil the ends of the coil being in direct contact with said flanges, twisting said wire about its axis as said wire is winding on said mandrel to give said wire torsional deformation within the elastic limit of the material of the wire, there being one complete twist for each convolution of the wire on the mandrel whereby the angle of said torsional deformation is substantially the same for each convolution of the coil, the direction of twist being opposite to the direction of ultimate unwinding during withdrawal of the wire from the coil, applying a rigid casing over and in direct contact with the outer layer of the coil, and anchoring said casing to said flanges to retain the latter in spaced relation.

2. The method of making a coil of wire adapted to deliver said wire by withdrawal therefrom at high delivery speed without rotation of the delivered wire relative to the coil and without development of torsional stress in the delivered wire, said method comprising winding wire of elastic metal on a rigid mandrel between rigid end flanges carried on said mandrel, rotating said mandrel to wind the wire thereon in a close substantially cylindrical helical coil the ends of the coil being in direct contact with said flanges, twisting said wire about its axis as said wire is winding on said mandrel to give said wire torsional deformation within the elastic limit of the material of the wire, there being one complete twist for each convolution of the wire on the mandrel whereby the angle of said torsional deformation is substantially the same for each convolution of the coil, the direction of twist being opposite to the direction of ultimate unwinding during withdrawal of the wire from the coil, applying a rigid casing over and in direct contact with the outer layer of the coil, anchoring said casing to said flanges to retain the latter in spaced relation, and removing the mandrel from within the coil after the casing has been anchored in position.

References Cited in the file of this patent UNITED STATES PATENTS 460,745 Duchemin Oct. 6, 1891 896,655 Monahan et al Aug. 18, 1908 1,063,646 Bournonville June 3, 1913 1,513,403 Lebeis Oct. 28, 1924 1,541,683 Buehler June 9, 1925 2,552,594 Scott, Jr. May 15, 1951 FOREIGN PATENTS 182,574 Great Britain Jan. 5,, 1922 745,997 France Feb. 27, 1933