US2431250A - Insulating device - Google Patents

Description

Nov. 18, 1947. 1.. R. HILL ET AL 2 L INSULATING DEVICE Filed Sept. 8, 1945 WITNESSES: 1

Patented Nov. 18, 1947 INSULATING DEVICE Lawrence R. Hill and John J. Keyes, Pittsburgh,

Pa., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application September 8, 1945, Serial No. 615,170

2 Claims.

This invention relates to devices for applying fibrous material to wire, 'and the like.

In the manufacture of insulated conductors, it is a common practice to apply a wrapping of fibrous material about a wire. The fibrous material is applied by some form of mechanism which usually spins about the wire and wraps the fibrous material helically thereon. Numerous devices for wrapping fibrous material have been proposed heretofore, and have been employed in the art. The prior are devices which have been employed for applying the fibrous material are characterized by certain disadvantages. A particularly undesirable feature is caused by the pull of the fibrous material on the wire during the wrapping operation. The devices have not held the wire satisfactorily, and the smaller and more flexible wire, or cable, has been pulled out of shape, or distorted, during the wrapping operation by the tension of the fibrous material. Furthermore, the fibrous material, particularly sliver, roving and yarn, has not been spread as effectively as desired so that the coating of fibrous material on the wire is relatively uneven and bunched. In many cases, polishers have been provided to cooperate with the prior art devices, in order to eliminate some of the unevenness of the applied wrapping. In many cases, the prior art devices had to be operated at a low rate of speed since the distortion of the wire caused excessive vibration and gave rise to other difiiculties.

The object of this invention is to provide a device for wrapping fibrous material upon wire, or the like, without causing deformation of the wire.

A further object of the invention is to provide a device for wrapping fibrous material upon wire, the device being capable of efficiently spreading the fibrous material on the wire to secure a smooth even wrapping and simultaneously polishing the wrapped fibrous material.

Other objects of the invention will, in part, be obvious and will, in part, appear hereinafter. For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description and drawing, in which:

Figure 1 is a view in elevation, partly in crosssection, of a machine for wrapping wire with fibrous material;

Fig. 2 is an enlarged View, in elevation, of the wrapping device proper;

Fig. 3 is a plan View of the device of Fig. 2;

Fig. 4 is a view, in elevation, of a modified form of device;

Fig. 5 is a plan view of the device of Fig. 4;

Fig. 6 is a schematic view, in plan, of still another modification of the invention;

Fig. '7 is a plan view of a fourth modification of the invention;

Fig. 8 is a schematic view of one mode of operation of the device of Fig. 2;

Fig. 9 is a schematic plan view of another mode of operation of the device of Fig. 2;

Fig. 10 is a schematic plan view of the third mode of operation of the device of Fig. 2; and

Fig. 11 is a schematic plan View of a fourth mode of operation of the device of Fig. 2.

Numerous forms and compositions of fibrous material may be applied to wire for producing insulated conductors and wrapped products. For example, cotton, paper, asbestos, glass fibers, cellulose acetate, regenerated cellulose, silk, superpolyamides, and similar materials may be applied as a wrapping. Thesematerials may be used as sliver, yarn, roving, continuous filament threads, highly twisted threads, and even in the form of tape. Combinations of two or more materials may be employed, such, for example, as a continuous filament fiber in combination with glass sliver, or asbestos sliver. Strips of paper tape, cambric tape, asbestos tape, regenerated cellulose tape, ethyl cellulose, and the like, treated with resins, adhesives and the like or untreated, may be applied to wire. The term fibrous material is intended to apply to these various materials.

The term wire, as employed herein, is intended to designate not only solid cylindrical material, but also to include stranded conductors and similar elongated strip material. The wire may be composed of copper, silver, iron, nickel, aluminum, and other selected materials suitable for any desired purposes. In some cases, the wire to be wrapped may be coated with enamels, adhesives, or other surface coatings in order to provide for any predetermined need.

We have produced a, wrapping device capable of applying any of the fibrous materials herein listed to wire of any size, including the finest wires, without causing deformation of the wire The fibrous materials are wrapped by the devicein a smooth and uniform coating or wrapping on the wire.

The wrapping device of this invention may be best understood by referring to Figure 1 of the drawing, showing a flier cup l0 having vertical side walls I! which may be rotated at a high.

rate of speed through the gear i4 driven from a suitable source of power. The flier cup ii] carries a hollow guide tube IE to permit the continuous passage of the wire 18 to be wrapped with a fibrous material 2%. The fibrous material 20 is supplied from a spool 22 fixed to and rotating with the flier cup I 0. The fibrous material 20 may be drawn from the spool 22 to the wall l2 of the casing by the post 2d fastened therein, and thence to the rings 26 and 28 fastened to the support 30 likewise attached to the wall i2. The fibrous material 20 is then returned.inwardly to the wrapping device proper 32 fastened to the flier cup ID by the threaded means 34 for rotation therewith. The wrapping applied to the wire I8 is shown as a coating 35.

It will be apparent that a plurality of the coatings 36 may be applied in any desired fashion to the wire It by a plurality of devices such as shown in Figure 1. The thickness of the coating of fibrous material will depend on the rate of passage of the wire l8 through the device of Fig. 1, as well as the speed of rotation of the device iii. Likewise, the amount of fibrous material in each strand 2'0 being applied will deter mine the relative thickness of the coating.

For a better understanding of the structure and operation of the wrapping device 32, reference could be had to Figs. 2 and 3 of the drawing, showing an enlarged view thereof. The device 32 comprises a main body 38 capable of being engaged by the spinning flier cup Hi. The body 38 is provided with a coned entrance 40 to permit the ready insertion of the wire to be wrapped into a longitudinal passageway :22. The longitudinal passageway 42 is slightly larger than the largest size of the wire to be wrapped by the device. In general, the size of the wire capable of being wrapped efiiciently by a single device will range from three to five sizes in the A. W. G. The upper part of the body is provided with an enlarged portion 44 having two flats 46 cut therein to provide for holding the device when it is being fitted into and being removed from the flier cup ID. The flange portion 44 carries two parallel pins 48 disposed longitudinally with respect to the passageway '42. A third guide pin '50 is provided behind the two pins 43. The two pins 4 8 are so spaced that there is an angle A of less than 180 between them with respectto the passageway 42. Furthermore, the two pins 50 are so spaced as to provide a narrow slotlike portion 52 for passage of the fibrous material between the pins to the wire l8 being wrapped. Each pin has a smooth longitudinal bearing surface 51 that extends over the passageway 42. The bearing surfaces will bear against and support the wire I8 as the wrapping of fibrous material is applied thereto. Furthermore, the bearing surfaces'tend to hold the wire l8 closely tothe center of rotation of the flier cup.

Referenceshould behad .toFig. l .of .the .drawmg showing agreatly enlarged schematic view of the device of Figs. '2 and .3, in operation ac cording to one mode of use .of the device. The fibrousmaterial 20 isdrawnaround the guide pin 50 into the slot 52 and wrappedabout the relativelynonerotating wire 18 as the entire .device 32 rotates in a counterclockwise direction. The fibrous material 20 is applied under tension and, in p g .over the guide pin 5i) and bearing against one of the longitudinal pins 48 thefibrous material isspread orfiattenedout. The tension oft-he fibrous materialfon wire 18 draws the wire l8 tightly against the pins 48 and center it in the axis of rotation, where it is supported on the two smooth longitudinal bearing surfaces 5|. The surfaces 5| are always in contact with the wire i8 over practically their entire length and prevent distortion or deformation thereof. The device 32' rotates about the center of the wire [8. Due to this continuous support and centering of the wire I8 undesirable vibration does not occur. The tension exerted by the fibrous material'2B not only provides for a tight wrapping thereof .on the wire I8, but also regulates the relative polishing action produced as the bearing surfaces 51 rotate in contact with the applied fibrous .material in coating 36. The joint result is that .a smooth, polished, and relatively uniform layer or coating 36 of fibrous material is .applied'to the wire l8.

A modified form of the wrapping device is illustrated in Figs. 4 and 5. of the drawing. The body be provided with the coned entrance 56 has a sector-shaped opening defined by walls 58 at one side leading to a longitudinal passageway 69 for the wire being treated. The flange portion 62 of the body carries two parallel longitudinal-pins 54 each provided with an eccentric cylindrical projection 65 fitting into a suitable cylindrical aperture in the flange portion 52.. The setscrews 66 provide for holding the projections 65 in any predetermined position. Behind the pinsfi i are located a pair of stationary guide pins 68. The advantages of the device of Fig. 4 are that the sector opening formed by walls 58 permits the device to be installed into or re moved from the wrapping machine without cutting the wire as would be necessitated bythe form of device shown in Fig. 2. Furthermore, a greater number of wire sizes may be accommodated satisfactorily by the single device of Fig. 4, simply by adjusting the pins 54 on the eccentric projections E5'to accommodate any size wire within its capacity most efiiciently.

in some cases, a somewhat simpler construction of wrapping device may be operated satisfactorily, such device being shown in Fig. 6 of the drawing. The device of Fig. 6, comprises a flange portion F2 to which are fastened longitudinally disposed pins M. The pins have bearing surfaces 5! for supporting the wire is as it is being wrapped by fibrous material that passes through the slot 52. The guide pin 59 as employed in the modification of Fig. 2 has been eliminated in the modification of Fig. 6. The mode-of operation of the device of Figure 6 will be detailed hereinafter.

For applying certain forms of fibrous materials to the wire, the modification shown in Fig. '7 has certainadvantages over the other modificationsshown. The device of Fig. '7 comprises a flange portion -16 upon whichare mounted two parallel pins 18 extending longitudinally of the passageway 42 and providing-a slot 52 for passage of the fibrous 2material'to the wire I8 being wrapped. Two guide pins .80 are disposed directly behind and parallel to-the pins E8. The device of Fig. 7 may be employed for wrapping fibrous materialin either direction about a conductor. Likewise, two different wrappings may be applied simultaneously, one wrapping being fed-over one of the guide pins .80 and the other wrappingoverpthe other guide pin-the innermost wrapping on the Wire beingapplied higher up on the one pin Eli! than the outermost wrapping being applied from the otherguide pin. The fibrousmaterial in passingovera pin-.80 and D 48 follows an S-shaped path which materially assists in spreading fibrous material.

In addition to the mode of operation of the device of Fig. 2 according to the schematic showing in Fig. 8, there are three other possible means of using the wrapping device. As illustrated in Fig. 9 of the drawing, the wrapping device may be operated in a clockwise direction about the relatively non-rotating wire 18. In this case, the fibrous material 20 passes over the pin 50 and thence through the slot 52 on the wire.

In Fig. 10, the wrapping device is operated in a clockwise direction, but the fibrous material 20 is fed over one pin 48 without making use of the guide pin 50. This causes less spreading of the fibrous material 20 than is secured by the modes of operation of Figs. 8 and 9.

In the mode of operation shown in Fig. 11 of the drawing, the device 32 operates counterclockwise and the fibrous material 20 passes over one pin 48 through the slot 52 and then to the wire l8 without passing over guide pin 50.

The modes of operation shown in Figs. 10 and 11 are necessarily employed in using the form of the device shown in Fig. 6 of the drawing, due to the absence of a guide pin in this modification of the device.

It will be appreciated that, since the wire upon which the fibrous material is being wrapped by the devices of this invention is supported effectively over substantially the full length of the pins, the wire will not be deformed or bent. Furthermore, the rigid, smooth, and centralized support afforded the wire greatly reduces, or practically eliminates, the vibration associated with devices hitherto employed in wrapping fibrous material on wire. No device known heretofore was capable of spreading loose fibrous material to the extent secured by the devices shown herein. Unusually smooth and uniform coatings of fibrous material have been produced on wire with the devices illustrated. The bearing surfaces of the pins in contact with the wire operate to polish the applied fibrous material in a manner highly satisfactory without crushing the applied material as occurs in many prior art devices. Less fuzz or nap is removed from the fibrous material by the present device than with prior art wrapping mechanisms. We have been able to operate the devices of this invention at a much higher rate of speed than devices previously employed in the art.

Since certain changes may be made in the above invention and different embodiments thereof can be made without departing from the scope thereof, it is intended that all matter contained in the above description or taken in connection with the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

We claim as our invention:

1. In a device for wrapping fibrous material on wire, in combination, a body having a longitudinal passageway for the wire, a pair of parallel pins on .the body disposed longitudinally of the passageway, the pins being located less than apart with respect to the passageway and providing a slot therebetween for passage of the fibrous material, one longitudinal surface on each pin being so disposed with respect to the passageway that wire being wrapped bears against and is supported by the surfaces, and a third longitudinal guide pin fastened to the body back of the slot parallel to the pair of pins and so located to guide the fibrous material ;to the slot that the fibrous material in passing over the third longitudinal pin and one of the pair of parallel pins follows an S-shaped path.

2. In a device for wrapping fibrous material on wire, in combination, a body having a longitudinal passageway for the wire and two differential recesses, and a pair of parallel pins on the body disposed longitudinally of the passageway, the pins having an eccentric cylindrical projection fitting into recesses in the body to provide for adjusting the relative positions of the pins to the body, the pins being located less than 180 apart with respect to the passageway and providing a slot therebetween for passage of the fibrous material, one longitudinal surface of each pin being so disposed with respect to the passageway that wire being wrapped bears against and is supported by the surfaces.

LAWRENCE R. HILL. JOHN J. KEYES.

REFERENCES CITED The following references are of record in the file of this patent:

Images