US2329653A - Tool installed wire connector - Google Patents

Description

Sep 1943- J. ROGOFF 2,329,653

TOOL INSTALLED WIRE CONNECTR Filed Oct. 14, 1941 "'iz/l///U///fl//l///////////fl/l///// //1///////// 77 27777777/l/////// lAl//l/ fim JULIAN ROGOFF INVENTOR.

V Patented Sept. 14, 1943 TOOL INSTALLED WIRE CONNECTOR Julian Rogoff, New Rochelle, N. Y., assignor to Burndy Engineering Company, Inc., a corporation of New York Application October l, 1941, Serial No. 414,!)

1 Claim.

My invcntion rclates to wire or cable connectors that are installed by means of pressureexerting tools and which may be used on wires subjected to tension.

The principal object of my invention is to provide a wire splice with a wire gripping surface, which will hold the wire so securely when the Connector is compressed onto the wire, that the wire will break before it will slip in the connector.

A further object is to provide a wire gripping surface that is created by controlled Chemical action. v

Another object of my invention is to provide a wire splice which will not injure or damage the wire in any way so that when tension equal to the ultimate strength of the wire is exerted on the wire, it will break at a point remote from the Connector.

Still another object of my inverition is to obtain a wire Connector which will provide an electrical connection of great eiciency with no unnecessary parts which may increase the current path and add contact resistances.

A further object of my invention is to obtain the objects outlined above in a wire Connector of minimum length and outside diameter. p

An important object of my nvention is to obtain all the preceding objects at minimum cost and in a manner adapted to mass production of r my wire splice.

I accomplish these and other objects and obtain new results as will be apparent from the device described in the following description, particularly pointed out in the attached claim, and illustrated in the accompanying drawing, which:

Fig. 1 is a longitudinal section of my wire splice.

Fig. 2 is an enlarged partial View of a cross section of my splice showing the etch'ed bore surface.

Fig. 3 is a view similar to Fig. 2 with the electroplating added.

Fig. 4 is a side View of my wire splice installed on wire ends with circumferential indentations. Fig. 5 is a section along line A-A of Fig. 3.

Fig. 6 is a view showing my splice provided with end plugs for processing purposes.

Referring to the drawing, and more particularly to Fig. 1, reference numeral !0 designates a wire splicing sleeve IO, comprising a tubular section of metal having a cylindrical bore II.

The conductors |2 and !3 are inserted in the two ends of the sleeve 10, and the walls !4, are compressed by an indenting tool creating preferably, an upper and lower substantially semicylindrical indentations l5 and IE, respectively, in juxtaposition to each other.

Wire splices have hitherto been made of sufllcient length to provide the necessary number of indentations or drawing length to insure proper resistance to the tension placed in the wires. In order to reduce the length of the splice, foreign hard particles have been introduced into the bore to "key" in the splice and the conductors during the indentation process; and increase the resistance values per unit of splice length', to the tension on the wires.

The ideal type of connection is one where the wires will break outside the splice, when the tension is brought to the breaking point of the conductors.

I obtain the keying' eifect by chemical action. This is accomplished by subjecting the bore alone to Corrosive action or by dipping the entire splice into a Corrosive solution, which attacksr the inner and outer surfaces of the splice and roughens them.

For example: If a Copper splice is treated then a solution of the following composition may be used:

H2SO4 ga1lons 1 HNO3 do 1 ZnSO4 pounds 2 ZnO2 d0 2 The splices may be immersed in the 'above solution at a temperature of l F. Alternatively a solution of the following composition may be used:

Sodium Dichromate ounces 3 Sulphuric Acid pints Water gallons 1 When the splices are removed from the solution they have a rough. matte finish. When the splice IU is indented on the wire end, as shown in Fig. 3. the numerous miniature hills l'i 'and valleys l8, shown in Fig. 2, key with the wire surface and provide a tight. secure grip. The roughened surface also bites into the surface of the wires (2 and |3 providing a contact surface of lower electrical resistance than splices provided with hard foreign particles since the electrical current does not have to pass through extra parts and between extra surfaces.

I have taken advantage of the fact that the crystalline structure of mctals facilitai es the process of etching" rough surfaces. Thus, I

the outside surface.

prefer to provide a splice made of alloys with constituent phases which will etch selectively in the manner well known to metallographers. Of especial advantage is the fact that the harder constituent in the alloy is usually attacked least by the etching agent, thereby providing hard mills to bite into the wire.

My Wire splice is cheap to manufacture since it consists simply of drawn tubes which may be imme'sed in large quantities in the etching agent. As a matter of fact, this last operation can be performed instead of the conventional cleaning operation and at approximately the same cost. Thus, my method of roughening the bore of the splice does not add anything to the cost of the splice.

Although I have described one method of providing a roughened bore for my Wire splice, other essentially similar methods can be employed. Thus, if I wish to control the number and shape of the hills and valleys" in the bore of my connector, I can control the etching process by any of the methods which are common amongst photoengravers, etc. These methods are more expensive than my preferred method, but under some circumstances they may prove advantageous.

Upon completion of the etching process on the splice, a hard metal, such as chromium may be electroplated thereon. A deposition of uniform thickness is inherent in electroplating. In this manner, the irregularities caused by the etching process may be covered with a hard metal facilitating the 'gripping action of the sleeve. 'I'he entire sleeve, or just the inside bore may be etched and electroplated.

In Fig. 6, one method is shown of etch'ng or electroplating the inside bore without affecting The ends of the sleeve 20 are provided with plugs 2l, which may be made of Wood, cork, rubber or some such suitable material. The splice is thereafter sprayed, or dipped in some material such as wax, which will prevent electroplating or the action of the etching acid. When this is done, the plug's are removed and the entire splice immersed or sprayed in the treating chemicals to produce the etching or electroplating with just the inside bore affected.

The bore of the splice may also be sprayed with a suitable material to prevent a smooth inner surface. The irregularities are created by electroplating only the unsprayed surface of the bore. These irregularities may dispense with the necessity for selective etching to create an uneven surface.

I have in the aforesaid specification used the words "Chemical action" to include acid etchina or electroplatlng and their Chemical equivalenir; which may be used to create irregularities in the bore in the material of the splice, or by adding other material.

I have found that a splice treated in the foregoing manner may be shorter in length and reduced in diameter over previous methods. My

devce is more economical to prepare, and the electrical joint efficiency is increased over pre vious types.

I have thus described my invention, but I desire it understood that it is not confined to the particular forms or uses shown and described, the same being merely illustrative, and that the invention may be carried out in other ways without departing from the spirit of my invention and, therefore, I claim broadly the right to em.-

.ploy all equivalent instrumentalities coming within the scope of the appended claims, and by means of which objects of my invention are attained and new results accomplished, as it is obvious that the particular embodiments herein shown and described are onlysome of the many that may be employed to attain these objects and accomplish these results;

I claim: i

A connecter for joining a conductor thereto comprising a. tubular sleeve made of malleable metal for transmitting electrical current from the conductor to the sleeve, having a roughened surface covered with a layer of uniform thickness of harder electrolytic metal, whereby the roughened andcovered surface may be compressed into the conductor for securing the two together.

JULIAN ROGOF'F.

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