US3617421A

US3617421A - Device for folding insulating tape about electrical conductors

Info

Publication number: US3617421A
Application number: US594097A
Authority: US
Inventors: Willard F M Gray; George C Lovejoy
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1966-11-14
Filing date: 1966-11-14
Publication date: 1971-11-02
Anticipated expiration: 1988-11-02

Abstract

A device for wrapping insulating tape longitudinally on electrical wire. The electrical wire and insulating tape will lead together with the wire on top of the tape into a first folding shoe. The first folding shoe folds one side of the tape about one side of the wire. A creasing member creases the tape tightly to the one side of the wire. A second folding shoe is provided beyond the first folding shoe, such second folding shoe folding the other side of the tape about the other side of the wire. A second creasing member creases the tape tightly to such other side of the wire. A strand of yarn is wrapped about the folded and creased tape holding such tape securely to the wire.

Description

United States Patent [72] lnventors [54] DEVICE FOR FOLDING INSULATING TAPE ABOUT ELECTRICAL CONDUCTORS 2 Claims, 10 Drawing Flgs.

[52] U.S. Cl 156/438, 252/54, 252/56, 252/202, 252/428, 252/463 [51] Int.Cl ..II0lb 13/26 [50] Field of Search 156/174,

[56] References Cited UNITED STATES PATENTS 2,133,620 10/1938 lsenberg 156/463 2,372,645 4/1945 Barmack 156/438 Primary Examiner-John T. Goolkasian Assistant Examiner-M. E. McCamish Attorneys-Gilbert P. Tarleton, Francis X. Doyle, Melvin M. Goldenberg, Frank L. Neuhauser and Oscar B. Waddell ABSTRACT: A device for wrapping insulating tape longitudinally on electrical wire. The electrical wire and insulating tape will lead together with the wire on top of the tape into a first folding shoe. The first folding shoe folds one side of the tape about one side of the wire. A creasing member creases the tape tightly to the one side of the wire. A second folding shoe is provided beyond the first folding shoe, such second folding shoe folding the other side of the tape about the other side of the wire. A second creasing member creases the tape tightly to such other side of the wire. A strand of yarn is wrapped about the folded and creased tape holding such tape securely to the wire.

PATENTED NUVZ 1971 SHEET 1 0F 2 DEVICE FOR FOLDING INSULATING TAPE ABOUT ELECTRICAL CONDUCTORS This invention relates to insulated electrical wire and more particularly to a device for applying insulation to an electrical wire and to the wire so insulated.

As is well known to those skilled in the electrical art, substantial use is made of electrical wire or conductors. Much wire is used to fonn electrical coils, to provide lease from one piece of apparatus to another, or to a source of electrical energy, and the like. In most uses of electrical wire it is required that the wire be covered with some type of electrical insulation. In the present state of the art most electrical wire is insulated by a continuous coating of a resinous film or by a helical wrapping of some type of insulating tape. While most resinous films are satisfactory for their intended use, the process for applying such films is relatively expensive and has a tendency to work harden the electrical wire. The helical wrapping is generally unsatisfactory for many uses since the wrapping tends to open or ravel when the wire is sharply bent or cut. Thus while the tape wrapping is less expensive than resinous film insulation its inherent disadvantages prevent its use in many applications.

To overcome some of the problems inherent in helically wound, tape-insulated, wire pairs, which are used mainly in telephone lines, it has been proposed to apply a plurality of layers of paper about each conductor of a pair in a longitudinal direction. This process is reported to require the use of a forming die employing heat and pressure. It is said that a minimum of two complete thicknesses of paper are required to enable the insulation to stay in place. It is understood that the heat and pressure requirements of this process will substantially increase the cost of the process over the helical winding process. However, it apparently can be more closely controlled to provide more reliable insulation and eliminate exposing of the conductor when the insulated pairs are bent. It also is reported that it prevents fraying of the conductors when such conductors are cut to make connections.

It has recently been discovered that a longitudinal tape insulation may be applied to electrical conductors without the use of heat and pressure. The device used to fold the insulating tape around the conductor is relatively simple and uncomplicated, thus providing a longitudinal tape insulation that is less expensive than comparable helically wound tape insula- IIOIIS.

It is therefore one object of this invention to provide a device for placing insulating tape longitudinally along an electrical conductor.

A further object of this invention is to provide an electrical conductor having a longitudinal tape insulation.

A still further object of this invention is to provide a device for placing tape longitudinally along an electrical conductor with means to secure the tape on the conductor.

in carrying out this invention in one form a device is provided for longitudinally folding an insulating tape along an electrical conductor. The device includes a pair of folding shoes mounted on opposite sides of the direction of travel of the electrical conductor and the insulating tape through the folding device. The conductor and tape are carried through the device in any desired manner such as by a driven takeup reel on which the insulated wire is wound. Means are also provided in the device for securing the folded tape to the conductor.

The invention which is sought to be protected will be particularly pointed out and distinctly claimed in the claims appended hereto.

However, it is believed that this invention, and the manner in which its various objects and advantages are obtained, as well as other objects and advantages thereof, will be more fully understood by reference to the following detailed description of a preferred embodiment thereof, particularly when considered in the light of the accompanying drawings, in which:

FIG. I is a diagrammatic view showing one type of apparatus for carrying out this invention;

FIG. 2 is an exploded perspective view of a folding and securing device according to a preferred embodiment of this invention;

FIG. 3 is a perspective view showing the operation of the folding means;

FIG. 4 is a sectional view of the wire and tape taken along the lines 4-4 of FIG. 3;

FIG. 5 is a sectional view of the wire and tape taken on the lines 5-5 of FIG. 3;

FIG. 6 is a perspective view of a rectangular wire insulated by a longitudinal folded tape according to the form of invention shown in FIGS. 2 thru 5;

FIG. 7 is a sectional view similar to FIG. 5 showing another form of tape fold according to this invention;

FIG. 8 is a sectional view similar to FIG. 4 showing two layers of tape folded about a conductor;

FIG. 9 is a sectional view similar to FIG. 5 showing the final fold of the form of folding shown in FIG. 8; and

FIG. 10 is a sectional view similar to FIG. 5 showing still another form of the folded tape insulation according to this invention.

Reference will now be made to the drawings in which like numerals are used to indicate like parts throughout the various views thereof. Referring first to FIG. I there is shown, in diagrammatic form, one type of apparatus for carrying out this invention. As is shown in FIG. 1 supply reels [0 and 12 are provided, reel I0 containing an uninsulated electrical wire 14 while reel 12 contains electrical grade insulating tape 16, such as, for example, kraft paper. Wire 14 may be any desired type and size of uninsulated electrical wire. A rectangular wire is shown throughout for purposes of illustration. Tape 16 is in the form of a flat ribbon, preferably being of a width such that it may be folded around wire 14 providing an overlapping segment, as will be more fully discussed. Both wire 14 and tape 16 are led through

rollers

18 and 20 to a tape-folding device 22 with wire 14 being fed on top of tape 16 as shown. Tape'folding device 22 folds the tape 16 tightly about wire 14 and secures tape 16 thereto preferably with an overlapped segment as will be more fully discussed. The insulated wire 24 is then fed to take up reel 26 where the insulated wire 24 may be stored until needed.

As will be understood, wire 14 and tape 16 may be fed through folding device 22 in any desired manner. For example, the tape 16 and wire 14 may be threaded through tapefolding device 22 and on to the takeup reel 26. Takeup reel 26 may then be driven in any desired manner drawing tape I6 and wire 14 through the tape-folding device 22.

FIG. 2 is an exploded perspective view of one form of tape folding device according to a preferred embodiment of this invention. As shown in FIG. 2, a preferred fonn of tape-folding device 22 includes the

rollers

18 and 20 through which the wire 14 and tape 16 are fed. A first folding shoe 28 is provided having a tapered and curved folding member 30 and a creasing member 32. Folding member 30 and creasing member 32 are mounted on a baseplate 34 which may be secured to tapefolding device 22 in any desired manner. As will be apparent from FIG. 2, wire 14 and tape 16 travel through the first folding shoe 28. As they travel through the shoe 28 the curved and tapered folding member 30 curves one side of tape I6 about wire 14. The taper forms tape l6 tightly against wire 14. The creasing member 32 then creases or sets the first fold of tape 16 against the side of wire I4, as is shown, and tightly against the top.

A second folding shoe 36 is provided including the curved, tapered member 38 and the creasing member 40. The curved member 38 and creasing member 40 are mounted on baseplate 42 which is also secured to folding device 22 in any desired manner. As can be seen, curved member 38 folds the other side of tape 16 tightly about wire 14 while creasing member 40 creases the folded tape l6 tightly thereto. In the preferred embodiment shown, creasing

members

32 and 40 are adjustably mounted on baseplates 34 and 42 respectively. As will be understood, the creasing

members

32 and 40 will be adjustable above the surface of wire 14 in accordance with the thickness of tape 16 being used. It is desirable that the creasing

members

32 and 40 be set just slightly higher over the surface of wire 14 than the thickness of tape 16 so as to provide a tight fold in tape 16 without tearing or wrinkling the tape. bviously, the exact height above the surface of wire 14 will depend upon the type of tape being used for insulation. It will generally be necessary to set the creasing members slightly higher for use of a paper tape than for one of the more durable plastic tapes which might be used for the insulation.

Where tape 16 is relatively stifl or thick or, for example, where more than one thickness of tape 16 is to be wrapped about conductor 14 at the same time, it is desirable to provide a flattening and bending member 44 between folding shoes 28 and 36. In the preferred embodiment shown in FIG. 2, the flattening member 44 is provided with a spring mounted flattening plate 46 which aids in the flattening of the first fold of tape 16 firmly to the top of wire 14. The baseplate 48 fits tightly against one side of wire 14, that is the side about which the tape has already been folded. The other side of baseplate 48 is provided with a curved side 50 which is slightly displaced from the opposite side of the wire 14. As will be understood the curved side 50 starts the fold on the other side of tape 16 before it travels through the second folding member 38 -of the folding shoe 36. Obviously, the curved member 50 of baseplate 48 may be displaced from the edge of wire 14 as desired to provide the beginning of the fold of the, second side of tape 16.

After tape 16 has been folded about wire 14 it is secured thereto. In the preferred form shown, tape 16 is secured in its folded position about wire 14 by means of a yarn wrapping. As is shown in FIG. 2, a yarn reel 52 is rotatably mounted in a carrier 54. Carrier 54 rotates about the insulated wire placing a serving of yarn 56 around insulated wire 24 thus firmly securing tape 16 in place to wire 14. It will be understood that carrier 54 may be driven about the insulated wire 24 in any desired manner, for example, by means of a driving gear (not shown).

FIG. 3 shows the sequence of folding tape 16 about wire 14 according to the preferred form of this invention. As is apparent from FIG. 3, tape 16 travels into folding device 22 with wire 14. The wire 14 is on top of and substantially in the center portion of tape 16. Folding shoe 28 first folds up one side of tape 16 about one side of wire 14 and flattens and creases the folded portion of tape 16 securely to the side and top of wire 14. The other side of tape 16 is then folded about the other side of wire 14 with the end of the second side overlapping the end of thefirst side on the top of wire 14 as shown. FIGS. 4 and 5 are sectional views taken on the lines 4-4 and 55 of FIG. 3, showing the first fold and beginning of the second fold, and then the flattening of the second fold, respectively. As can be seen, the wire 14 is completely surrounded by folded tape 16 which completely insulates the wire 14.

FIG. 6 is a perspective view of the single tape 16 overlapped on the wire 14 providing insulated wire 24. As is apparent from FIG. 6, the tape 16 completely surrounds the wire 14 overlapping at the top as shown. Thus it is apparent that by means of the folding device of this invention that a longitudinally insulated taped wire is provided, with neither heat nor pressure being required to fold the tape about the wire member.

of course, it will be apparent that it is not necessary that the folded tape 16 overlap on the top of wire 14. FIG. 7 shows a folded insulation in which tape 16a is provided with a butt wrap about wire 14. Sometimes it is desired that the insulation be completely uniform without any irregularities as would occur with an overlapping of the tape 16. In such instances, the tape may be made just wide enough to butt when folded over wire 14. By using tape 160 the ends of the tape may just touch at the top of wire 14 providing a butt wrap, as shown in l FIG. 7. This folded insulation may be especially useful in winding certain type of precision coils.

Other types of folded insulation may also be provided according to this invention. For example, instead of a single tape, two or more strips of insulated tape-may be fed into folding device 22. Of course, these tapes may come from a single reel, or from a plurality of reels. FIGS. 8 and 9 show one form of double insulation that may be provided according to this invention. As is shown in FIGS. 8 and 9, a pair of insulated tapes 16b and are folded together about the wire 14. Tape 16b is slightly narrower than tape 16c such that as shown, particularly in FIG. 9, tape 16b provides a butt wrap about wire 14, while tape 16c provides an overlap wrap about wire 14. In the form shown in FIGS. 8 and 9, both insulating tapes 16b and 160 are fed to folding device 22 at the same time, with tape 16b on top of tape 16c and closest to wire 14.

In another form of the invention additional folding shoes may be provided and separate layers of insulated tape placed about the wire 14, one after the other. One type of folded insulation that may be obtained by this means is shown in FIG. 10. As shown in FIG. 10, a first layer of insulated tape 16d is folded about wire 14. This may be either a butt wrap or an overlap wrap as desired. A Butt wrap is shown in FIG. 10. Then a second layer of insulated tape 16 is folded over the first layer as shown. This also may be with either a butt wrap or an overlap wrap. As is shown in FIG. 10, both layers are provided as a butt wrap, with the butt ends being staggered over the top of wire 14. Thus it is apparent, that by means of the invention, various types of folded insulation may be provided longitudinally along an electrical conductor to provide any desired type of insulation.

From the above it will be apparent that this invention provides a means of placing an insulated tape longitudinally about an electrical conductor to properly insulate such conductor. Obviously, many different types of insulated tape may be used and any desired form of wrap may be used. While there has been shown and described, the present preferred embodiment of the invention, it will be apparent that various changes may be made without departing from the invention particularly as it is set forth in the appended claims.

What is claimed as new and which it is desired to secure by Letters Patent of the United States is:

1. A folding device for longitudinally folding insulating tape about an electrical conductor comprising:

a. roller means for leading an electrical conductor and at least one layer of insulating tape into a folding device,

b. a folding shoe on one side of the direction of travel of'said conductor and said tape,

1. said folding shoe including a curved, tapered member for folding one side of said tape about one side of said conductor,

2. a creasing member as part of said folding shoe for creasing said one side of said tape tightly to one side of said conductor,

c. a second folding shoe mounted opposite to said one folding shoe along the direction of travel of said conductor and said tape,

1. said second folding shoe including a curved and tapered member for folding the other side of said tape about the other side of said conductor;

2. a creasing member as part of said second folding shoe for creasing said other side of said tape tightly to said other side of said conductor whereby said tape is folded longitudinally about said conductor.

2. A folding device for longitudinally folding insulated tape about an electrical conductor as set forth in claim I in which means are provided for securing said tape in said folded position about said conductor.

Claims

2. a creasing member as part of said folding shoe for creasing said one side of said tape tightly to one side of said conductor, c. a second folding shoe mounted opposite to said one folding shoe along the direction of travel of said conductor and said tape,
2. a creasing member as part of said second folding shoe for creasing said other side of said tape tightly to said other side of said conductor whereby said tape is folded longitudinally about said conductor.
2. A folding device for longitudinally folding insulated tape about an electrical conductor as set forth in claim 1 in which means are provided for securing said tape in said folded position about said conductor.