US3905668A

US3905668A - Sealing band for electrical connector

Info

Publication number: US3905668A
Application number: US447455A
Authority: US
Inventors: Thomas A Gee
Original assignee: Eaton Corp
Current assignee: Eaton Corp
Priority date: 1974-03-01
Filing date: 1974-03-01
Publication date: 1975-09-16
Anticipated expiration: 1992-09-16

Abstract

An electrical connector is provided of the type including at least a pair of insulated wires, a wire connector electrically attached to each of the wires, and an elastomeric insulating body encasing at least a portion of the wire connectors and the terminal portions of the wires. The insulating body is preferably injection molded, but does not bond to the insulation on the wires. An elongated sealing band is compressively formed about the periphery of the insulating body, to compress the body tightly about each of the insulated wires to minimize the ''''backside leakage.'''' Preferably, the sealing band is formed into a configuration which exerts a force on the insulating body to compress it radially toward each of the insulated wires around a major portion of the wire.

Description

United States Patent [1 1 Gee 1 1 SEALING BAND FOR ELECTRICAL CONNECTOR [75] Inventor: Thomas A. Gee, Allen Park, Mich.

[73] Assignee: Eaton Corporation, Cleveland, Ohio [22] Filed: Mar. 1, 1974 21 Appl. No.; 447,455

[52] [1.8. CI 339/60 M; 174/65 G; 339/101 [51] Int. Cl. A t HOlR 11/28 [58] Field of Search 339/47-49, 339/59-61, I01, 103 M, 103 R; 174/77 R, 65 G [56] References Cited UNITED STATES PATENTS 2,311,427 2/1943 Winkelmeyer..... 174/65 G X 3,026,495 3/1962 Quackenbush. 339/103 R X 3,059,214 10/1962 Heller 339/49 R X 3,199,060 8/1965 Marasco t 339/60 R 3,518,615 6/1970 Sparks et al 339/103 M X FOREIGN PATENTS OR APPLICATIONS 1,073,100 3/1954 France 339/101 [451 Sept. 16, 1975 Primary Examiner-Joseph H. McGlynn Assistant Examinerl-loward N. Goldberg Attorney, Agent, or FirmTeagno & Toddy ABSTRACT An electrical connector is provided of the type including at least a pair of insulated wires, a wire connector electrically attached to each of the wires, and an elastomeric insulating body encasing at least a portion of the wire connectors and the terminal portions of the wires. The insulating body is preferably injection molded, but does not bond to the insulation on the wires. An elongated sealing band is compressively formed about the periphery of the insulating body, to compress the body tightly about each of the insulated wires to minimize the backside leakage. Preferably, the sealing band is formed into a configuration which exerts a force on the insulating body to compress it radially toward each of the insulated wires around a major portion of the wire.

8 Claims, Drawing Figures PMENTEU SEP I 61975 SiIIET 2 OF 3 FIG. 2

FIG. 3

SEALING BAND FOR ELECTRICAL CONNECTOR BACKGROUND OF THE DISCLOSURE The present invention relates to electrical connectors having elastomeric encasements around the wires, and more particularly, to such connectors which are subjected to an atmosphere of moisture and salt, or which connect wires which must maintain a substantially constant electrical resistance.

It is frequently desirable to make an electrical connection, between a pair of circuit elements, which may be readily disconnected. This may be accomplished by forming on each pair of leads, emanating from a circuit element, an electrical connector having a male connector attached to one lead and a female connector attached to the other lead. Around these connectors, an insulating body is provided, having a configuration such that two identical connectors can be mated.

Many uses of this type of connector subject it to various environments including, as matters of example rather than limitation, moisture, salts, acids, tar, asphalt, and oil. For example, a connector of the type described is used in vehicle anti-skid brake systems to effect an electrical connection between the wheel speed sensor and the controller, between the power leads and the controller, and in the fail-safe warning unit connections. Whenever electrical connectors of the class described are utilized in sensing circuits, or in various other sensitive circuits, it is important that the combination of the leads between the circuit elements being connected and the connectors between those leads maintain a substantially constant electrical resistance. Therefore, the backside leakage" of, for example, moisture or moisture mixed with salt into the connector between the wires and the insulating body must be minimized, as the moisture and salt can cause the oxidation of the wires, thereby increasing the resistance.

In addition, the leads from certain circuit elements may include a section of fine wires, emanating from the circuit element, soldered to a section of larger wires. If salt is permitted to enter the connector, it may wick" or be cohesively transferred from the connector along the larger wires to the joint where it may corrode the soldered joint and/or the smaller wires, thus causing an electrical discontinuity.

SUMMARY OF THE INVENTION vention to provide an electrical connector in which a seal is effected by compressing the insulating body radially toward each of the leads around a major portion of the lead.

These and other objects of the present invention, which will become apparent upon a reading of the following detailed description, are accomplished by the provision of an electrical connector of the type including at least two spaced-apart, insulated wires, a wire connector electrically attached to each of the insulated Print-W. .M.

wires, and an elastomeric insulating body encasing at least a portion of each of the wire connectors and the adjacent portions of the insulated wires. An elongated sealing band is compressively formed about substantially the entire periphery of the elastomeric insulating body to compress the insulating body tightly about the insulated wires to minimize the leakage of moisture therebetween.

In accordance with another aspect of the present invention, a method is provided for sealing an elastomeric insulating body about a pair of spaced-apart, insulated wires encased by the body. A generally flat sealing band is provided having a length approximately equal to the peripheral dimension of the insulating body. The band is formed about substantially the entire periphery of the insulating body to compress it tightly about each of the insulated wires. Preferably, the band is formed into a configuration, such as a figure-8, which exerts a force on the insulating body which compresses the body radially toward each of the insulated wires around the major portion of the wire.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a connector made in accordance with the present invention.

FIG. 2 is a cross-sectional view of the connector before the sealing band is added.

FIG. 3 is a cross-sectional view taken on line 3-3 of FIG. I, after the sealing band is added.

FIGS. 4 and 5 are partly schematic illustrations of the method of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings which are for the purpose of illustrating preferred embodiments of the present invention and not for limiting the same, FIG. I is a plan view of an electrical connector made in accordance with the present invention. The connector, generally designated by the numeral 10 includes a pair of insulated leads l2 and 14. Electrically attached to the lead 12 is a female wire connector (not shown) and electrically attached to the lead 14 is a male wire con nector 16. An elastomeric insulating body 18 totally encases the female wire connector and encases a portion of the male wire connector 16 as well as the terminal portions of the leads l2 and 14 adjacent the respective connectors. The manner of making an electrical connection using the connector 10 is shown in FIG. I by the position of the mating connector 10' and the male wire connector 16'. It should be clearly understood, however, that the scope of the present invention is in no way limited to the use of the particular malefemale connector arrangement shown, or the configuration of the insulating body 18.

FIG. 2 is a cross-sectional view, similar to FIG. 3, after the insulating body 18 has been formed to encase the wires 12 and I4. Insulating body 18 is preferably made from a material which is electrically nonconductive such as neoprene or polyvinyl chloride. The leads l2 and I4, with the wire connectors attached, may be held in place within a suitable mold and the elastomeric or polymeric material injection molded to encase the wires, the female wire connector and a portion of the male wire connector 16. As used herein, the reference to the material for the body 18 being elastomeric or polymeric is meant to mean and include any organic (carbon-based) material which is classified as an electrical insulator and which displays resilient, elastic properties. The teachings of the present invention are especially advantageous when used on a connector in which the elastomer of the insulating body 18 does not moldbond to the insulation of leads l2 and 14, i.e., become joined thereto by chemical reaction or thermal fusion during the molding and subsequent curing. ln the subject embodiment, the insulation on leads l2 and I4 is a form of cross-linked polyethylene and the insulating body 18 is polyvinyl chloride, typically having a hardness, on the Shore A scale, from about 60 to about 80. Therefore, as shown in FIG. 2, there is no bond or adherence between the insulation and the insulating body to prevent the leakage of moisture and salt therebetween.

FIG. 3 is cross section of the connector after the sealing band 20 has been formed about the periphery of the insulating body 18. To facilitate the positioning and crimping of the sealing band 20 about the insulating body IS, the body 18 may have a recess or depression (not shown) formed in its outer surface during the molding operation to act as a seat for the sealing band. In the subject embodiment, the sealing band 20 is made from cold-rolled steel and is zinc plated, although it should be clearly understood that the band may also be stainless steel or any one of a number of metallic or non-metallic materials as long as the material has a sufficient flexural modulus to enable the sealing band to maintain its configuration about the insulating body once the band has been crimped or swaged to that configuration.

FIGS. 4 and 5 illustrate semi-schematically one of the preferred methods for forming the sealing band in place about the insulating body. In FIG. 4, the straight sealing band 20, in dotted line form, is placed on the upper face of the fixture 30. The forming tool 32 descends, engaging the intermediate portion 22 of the sealing band 20 and forcing it into the fixture cavity 34 until the band is formed as shown in FIG. 4, with

terminal portions

24 and 26 of the band 20 remaining vertical. The succeeding crimping operation may be performed with the band still in fixture 30, or the band may be placed in another, but similar fixture. It will be assumed herein that the band 20 remains in the fixture 30.

FIG. 5 illustrates the crimping operation, by which

terminal portions

24, 26 of the sealing band 20 are formed so as to complete the generally 8-shaped configuration of the band as shown in FIG. 3. As shown in FlG. 5, a crimping tool 36 may be used, having a crimping surface 38, which engages

terminal portions

24 and 26 of the band and forms said portions to complete the desired configuration of the band (refer to FIG. 3). In the subject embodiment, by way of example, the sealing band 20 has a thickness of about 0.060 inch, a length about 1.7 inch and a width of about 0.15 inch. For a band of these particular dimensions, a force of approximately 1,000 lbs. was applied to the forming tool 32, while the crimping operation was performed under a force of approximately 3,000 lbs.

It should be noted that the illustration of a two-wire connector and the generally 8-shaped configuration of the band are not intended as limitations on the scope of the invention. Rather, the more important aspect of the band configuration is that it compresses the insulating body radially toward each of the insulated leads around a major portion of each lead. The figure-8 shape is preferred because it is simple to form and provide generally uniform compression of the insulating body, even in the central portion of the body where the band is indented to form the figure-8.

The invention has been described in great detail sufficient to enable one of ordinary skill in the art to make and use the same. Obviously, modifications and alterations in the preferred embodiments will occur to others upon a reading and understanding of the specifica tion and it is my intention to include all such modifications and alterations as part of my invention insofar as they come within the scope of the appended claims.

I claim:

1. An electrical apparatus of the type subjected to an atmosphere of moisture and salt, comprising:

a. first and second circuit elements, said elements including, respectively, first and second pairs of insulated leads having terminal portions;

b. first and second mating electrical connectors attached, respectively, to said first and second pairs of insulated leads, each of said electrical connectors comprising:

i. a wire connector electrically attached to said terminal portions of each of said leads,

ii. an elastomeric insulating body, having a lead end and a connector end, and encasing at least a portion of each of said wire connectors and said terminal portions of said leads, said elastomeric insulating body having a generally oval cross section in its uncompressed state; and

iii. an elongated sealing band compressively formed about substantially the entire periphery of said elastomeric insulating body, adjacent said lead end thereof, said sealing band being formed into a non-circular configuration which exerts a force on said insulating body to compress the portions of said insulating body adjacent said conductors radially toward each of said conductors around a major circumferential portion thereof to minimize the leakage of moisture therebetween.

2. The electrical apparatus of claim 1 wherein said first and second circuit elements comprise a portion of a vehicle anti-skid brake system.

3. The electrical apparatus of claim 2 wherein said first circuit element is a wheel speed sensor and said second circuit element is a logic controller.

4. The apparatus of claim 1 wherein said leads are required to maintain a substantially constant electrical resistance.

5. The apparatus of claim 1 wherein said sealing band is formed into a configuration which is generally 8- shaped.

6. An electrical connector including at least two spaced apart insulated conductors, a connector electrically attached to each of the insulated conductors, an elastomeric insulating body having a conductor end and a connector end:

a. said insulating body encasing at least a portion of each of the connectors and the adjacent portions of the conductors and having a non-circular cross section in its uncompressed state;

b. an elongated sealing band compressively formed about substantially the entire periphery of said insulating body, adjacent the wire end thereof; and

c. said sealing band being formed intoa non-circular 7. An electrical connector as defined in claim 6 configuration which exerts a force on said insulatwherein said insulating body has a generally oval cross ing body to compress the portions of said insulating section in its uncompressed state. body adjacent said conductors radially toward each 8. An electrical connector as defined in claim 7 of said conductors around a major circumferential 5 wherein said sealing band is formed into a configuraportion thereof to minimize the leakage of moistion which is generally 8-shaped. ture therebetween.

Claims

1. An electrical apparatus of the type subjected to an atmosphere of moisture and salt, comprising: a. first and second circuit elements, said elements including, respectively, first and second pairs of insulated leads having terminal portions; b. first and second mating electrical connectors attached, respectively, to said first and second pairs of insulated leads, each of said electrical connectors comprising: i. a wire connector electrically attached to said terminal portions of each of said leads, ii. an elastomeric insulating body, having a lead end and a connector end, and encasing at least a portion of each of said wire connectors and said terminal portions of said leads, said elastomeric insulating body having a generally oval cross section in its uncompressed state; and iii. an elongated sealing band compressively formed about substantially the entire periphery of said elastomeric insulating body, adjacent said lead end thereof, said sealing band being formed into a non-circular configuration which exerts a force on said insulating body to compress the portions of said insulating body adjacent said conductors radially toward each of said conductors around a major circumferential portion thereof to minimize the leakage of moisture therebetween.

5. The apparatus of claim 1 wherein said sealing band is formed into a configuration which is generally 8-shaped.

6. An electrical connector including at least two spaced apart insulated conductors, a connector electrically attached to each of the insulated conductors, an elastomeric insulating body having a conductor end and a connector end: a. said insulating body encasing at least a portion of each of the connectors and the adjacent portions of the conductors and having a non-circular cross section in its uncompressed state; b. an elongated sealing band compressively formed about substantially the entire periphery of said insulating body, adjacent the wire end thereof; and c. said sealing band being formed into a non-circular configuration which exerts a force on said insulating body to compress the portions of said insulating body adjacent said conductors radially toward each of said conductors around a major circumferential portion thereof to minimize the leakage of moisture therebetween.

7. An electrical connector as defined in claim 6 wherein said insulating body has a generally oval cross section in its uncompressed state.

8. An electrical connector as defined in claim 7 wherein said sealing band is formed into a configuration which is generally 8-shaped.