WO1990008387A1

WO1990008387A1 - Rigid electrical wire

Info

Publication number: WO1990008387A1
Application number: PCT/US1990/000299
Authority: WO
Inventors: Mark Spencer
Original assignee: W.L. Gore & Associates, Inc.
Priority date: 1989-01-17
Filing date: 1990-01-16
Publication date: 1990-07-26
Also published as: AU5040490A

Abstract

A process is described for rigidifying desired portions of flexible electrical wire by applying a settable composition and bending the wire to a desired configuration, followed by setting the settable composition.

Description

RIGID ELECTRICAL WIRE

FIELD OF THE INVENTION

This invention relates to electrical cable having at least one rigidified portion, and to a process for making the cable.

BACKGROUND OF THE INVENTION Electrical wire and cable comes in many forms, from ordinary house wiring to more complex and precise coaxial cable. In virtually all instances, the wire and cable is flexible.

However, it is sometimes desirable to maintain portions of the wire or cable in a rigidified configuration; as for example, in confined applications where space is limited and the natural bend radius of a flexible cable is to large to allow efficient routing, or where it is necessary for cables to follow the contour of a chassis for various reasons. Heretofore, the cable has been held in place with clamps. Another instance is when it is necessary to have a low profile bend in a cable immediately behind a connector for routing requirements and have such bend oriented at some degree in relationship to a connector at the other end of said cable which may also have such a bend. Various mechanical devices, such as tubes, cast elbows and polymer sleeves are presently used for the later instance. The method of rigidizing flexible cable herein described alleviates the necessity of external mechanical fastening and forming devices described above.

It is desirable to provide a cable with rigid portions that can be formed when and as desired. SUMMARY OF THE INVENTION

This invention provides a process for transforming portions of a flexible cable into any desired rigid configuration by:

(1) applying a settable composition, such as solder or an epoxy, to a flexible electrical wire or cable at an area of the wire or cable wherein dielectric material surrounding the conductor element is exposed; (2) conforming, to a desired configuration, as for example by bending the wire or cable at the area where the settable compound has been applied; and

(3) causing said settable composition to set.

Among the preferred embodiments of the invention are the following:

A process in which the steps are to:

(1) remove the insulation, if present, from the cable in the portion to be rigidified; (2) wrap said portion with a suitable strip of solder; (3) bend or form said portion to a desired configuration; (4) apply heat adequate to melt solder; (5) cool in place.

A process in which the steps are to:

(1) remove the insulation, if present, from the cable in the portion to be rigidified; (2) massage solder paste into the shieldings in said portion of cable; (3) bend or form said portion to a desired configuration; (4) apply heat adequate to melt solder; (5) cool in place.

A process in which the steps are to:

(1) remove the insulation, if present, from cable in the portion to be rigidified; (2) bend or form said portion to a desired configuration; (3) submerge said portion into a molten solder bath; (4) remove from said bath and cool in place.

A process in which the steps are to:

(1) remove the insulation, if present, from cable in the portion to be rigidified; (2) massage an adequate epoxy into the shielding in said area; (3) bend or form said portion to a desired configuration; (4) cure epoxy in place.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 depicts an electrical wire or cable in which the outer layers have partially stripped away. Figurs 2 depicts the same wire or cable wrapped with a solder strip in the stripped away area. Any other settable, or

rigidizing agent, can be used in place of the solder strip.

DESCRIPTION OF THE INVENTION In wires and cables, various conductor wires are surrounded with insulating material. These constructions are frequently then surrounded with a conductive braid or shielding and then with a final outer covering of protective insulation.

The interior configuration of the wire or cable is not important in this invention. The invention is equally applicable to single wire construction or multiple wire construction, twisted or otherwise. The terms "wire" and "cable" are used

interchangeably.

These wire and cable construction can usually be flexed to fit any desired configuration. In such instances the outer protective insulation may be stripped away, allowing the rigidifications, previously described, as without seriously degrading the

electrical performance of such a wire or cable.

This layer needs stripping away so that the outer

shielding/conductor of the cable is exposed such that one of various materials may be either wrapped around or massaged into this shielding. Stripping can be accomplished by desired means, such as slitting and radial cutting with a knife or razor blade. The next step can be to apply a material or substance (settable or rigidizing agent) to the exposed shielding which can or will subsequently be transformed into a semi homogeneous binder or rigidizer. Any suitable material may be applied, such as solder wrapping with wire or strip solder, massaging solder paste into the exposed area or massaging an epoxy/glue into the exposed area. The area can then be formed to a desired shape and the material then set by transformation into semi homogeneous or binding form. In the case of solder wire, strip, or paste, heat is applied from a source adequate to melt said solder. Some heat sources that can be used include a resistance soldering unit, an induction unit, a heat gun, a solder iron, an oven and the like. If desired, nothing may be applied to the exposed area but the area may be formed and then simply submerged into a solder bath and removed to cool. If epoxy is used curing methods recommended by the epoxy manufacturer may be followed.

The invention is now described with reference to the

drawings. Figure 1 shows a typical coaxial electrical cable construction with an outer protective insulative jacket 1 stripped back to expose underlying remainder of the conductor or shield 2. These layers surround the principal dielectric material 3 of the cable which surrounds an electrical conductor 4. Figure 2 depicts the wire of Figure 1 in which the stripped area has been wrapped with solder wire 5. The wire can then be shaped and the solder melted to obtain the rigid product.

Claims

I Claim:

1. Process for transforming a portion of a flexible wire or cable into a rigid configuration, which comprises: (a) applying a settable composition to a flexible electrical wire or cable at an area of the wire or cable wherein dielectric material surrounding the conductor element is exposed;

(b) conforming the wire or cable at the area where the settable compound has been applied to a desired configuration;

(c) causing said settable composition to set.

2. Process of Claim 1 in which the settable composition is solder wire.

3. Process of Claim 1 in which the settable composition is solder paste.

4. Process of Claim 1 in which the settable composition is an uncured epoxy compound.

5. Process of Claim 2 wherein in step (3) the solder is heated until it melts and is then cooled.

6. Process of Claim 3 wherein in step (3) solder paste is heated until it melts and is then cooled.

7. The process of Claim 4 wherein in step (3) uncured epoxy is caused to cure.