US 3757276 A
A high-temperature electrical connector including interengageable mating sections each having a central and an outer-tubular metallic contact and an insulating sleeve disposed therebetween with the insulating sleeve of the one section having self-lubricating surfaces of a fluorocarbon engaging the sleeve or its associated outer-tubular metallic contact of the other section, the fluorocarbon having a relatively low heat deflection temperature so as to deform at high temperatures. The other insulating sleeve is composed of a material such as an aromatic polysulfone with a relatively high heat deflection temperature to provide a relatively rigid support for the fluorocarbon sleeve.
Description (OCR text may contain errors)
United States Patent 1 Kailus [451 Sept. 4, 1973 CONNECTOR MODULE  Assignee: Bunker Ramo Corporation, Oak
 Filed: Sept. 7, 1971  Appl. No.: 178,097
Primary Examiner-Richard E. Moore Attorney-Frederick M. Arbuckle [5 7] ABSTRACT A multi-connector bussing module for aircraft use at temperatures of 400500F. including a plurality of two-contact connectors in which a plurality of protected inner contacts are interconnected by a hollow bus ring and protective outer contacts in association with the inner contacts are spacially separated around a hollow interior; an insulative body of hightemperature plastic extending in juxtaposition over the bus ring to the protective contacts; and a relatively thin metallic coating being adherently affixed to the insulative body to provide an electrically protective shield and also to interconnect the protective outer contacts of two or more connectors. The assembly of connectors and bus ring also forms an electrically protective enclosure around the hollow interior, shielding a plurality of one-contact connectors with two or more of the contacts being interconnected by an inner bus ring.
18 Claims, 6 Drawing Figures PATENTEusEr 4mm 3. 757' 276 56 Inventor Wllllam FLKaHus aq'Horne} PATENTEDSEP'MHYS 3,757, 276
SHEET 3 0F 4 nven'l'or PATENTEUSEF 4W 3.757. 276
Inventor William AKailus l'ftornel CONNECTOR MODULE BACKGROUND OF THE INVENTION In the instrumentation field, multi-connector modules have been used to interconnect circuits associated with various sensing elements to instruments for the detection, measurement, or control of the phenomena being sensed. In the measurement of liquid levels in an aircraft fuel tank, such modules have been used to interconnect a plurality of capacitance sensing elements located within the fuel tank with one or more fuel supply indicating instruments in the aircraft. Generally, a number of such sensing elements positioned at spacedapart locations in the fuel tank are'themselves interconnected or bussed" together to compensate for the variations in fuel level produced by changes in the attitude of the aircraft during flight and thus provide a compensated or averaged indication of the fuel supply.
As the performance requirements of aircraft have been increased, there has often been an increase in temperatures and temperature variations to which various components including the multiconnector modules are exposed. In some instances, requirements have been set for modules to perform under temperatures as high as 500"F. and above, together with temperature variations of from sub-zero to 500F. Under these conditions, many modules suffer deterioration, heat distortion, insulation breakdown, unequal expansion of the various metallic and non-metallic connector parts and the like. These effects act to interrupt the individual connections between connectors and adversely affect the impedance characteristics of the modules. As an example of the problem, materials in the modules have an insulative quality which can deteriorate with increasing temperatures, and at 500F., sufficient heat can be generated as to actually cause a breakdown of insulation between contacts. When some of the insulators are buried within the module, it is not always apparent on the instruments when signal valves on the instruments are inaccurate due to deterioration or breakdown of the insulation.
It is also important that these multi-connector modules be constructed so as to be of limited weight and size in view of their use in aircraft. In many instances, the combination of requirements of performance at high temperatures with reasonable valves of weight and size can significantly complicate the design of the modules.
Therefore, it is commercially important that new multi--connector modules be provided for use on aircraft and that these modules perform under extreme temperature conditions without being of excessive weight or size.
SUMMARY The invention is directed to a high temperature multi-connector module for use in aircraft at temperatures of about 400-500 F. and more particularly to a compact multi-connector molule in which two or more connectors are internally interconnected or bussed. The module comprises two or more electrical connectors in juxtaposition with each other, an insulative body, preferably of one-piece construction formed over at least a portion of two or more of the connectors, and a metallic coating adherently affixed to at least a portion of the insulative body to interconnect the connectors.
More particularly, the insulative body is a high temperature thermoplastic and preferably an aromatic polysulfone capable of adherently receiving a thin metallic coating which at temperatures of about 400-500F. does not separate from the insulative body and does not exhibit silver migration. The module is particularly useful with two contact connectors having protected or shielded contacts and in one embodiment comprises a plurality of two-contact connectors arranged around a bus ring or other means for interconnecting at least a portion of at least one of the contacts in each of two or more connectors. An insulative body, preferably of one-piece construction, is molded around the outer surface of the bus ring and serves to insulatively separate the inner contact from the outer contact in each connector while also insulating the portion of the bus ring adjacent to the inner contact. The metallic coating is adherently affixed to the outer surface of the insulative body and extends between two or more of the outer contacts of the connectors. In a particularly useful form, the metallic coating serves as a shielding for both the bus ring and portions of each of the individual connectors. In some instances, the metallic coating may extend around in spaced relationship with each of the inner contacts as individual shields and is adherently affixed to an inner insulative sleeve, preferably composed of a high-temperature plastic.
Advantageously, the two-contact shielded connectors are disposed on a bus ring in an outer connector assembly to form a hollow interior adapted to receive one or more additional assemblies of connectors. In this arrangement, the outer connector assembly both houses and shields the inner connectors. Flat, disc-like spacers are also positioned within the hollow interior and serve to insulatively separate and mount the connectors. Front and rear inserts with passages adapted to receive frontwardly and rearwardly disposed connectors are then positioned around the outer and inner connector assemblies, spacers, and additional connectors.
One of the advantages of the multi-connector module of the invention is that it is capable of satisfactory performance at high temperatures without insulation breakdown. Another advantage is that the metallic coating is adherently attached to the insulative body and also capable of performance at these temperatures without flaking or otherwise becoming separated from the body. A further advantage is that the metallic coating provides individual shielding of the outer connectors and also shields the inner connectors. In addition, the entire assembly provides a housing containing a plurality of one and two-contact connectors while being of relatively low weight and size.
DESCRIPTION OF THE DRAWINGS FIG. 5 is an enlarged front sectional view of the module of FIG. 1.
FIG. 6 is a partial side view of another embodiment of the connector of FIG. 3.
GENERAL DESCRIPTION The module comprises one or more forwardly disposed two-contact connectors in juxtaposition with one or more other two-contact connectors which are'usually rearwardly disposed. Each contact is insulatively separated from the other contact and is adapted for connection to an external conductor. A bussing ring or other means is provided for interconnecting an inner or a first contact of two or more of the connectors and is interposed between the forwardly disposed and rearwardly disposed connectors. An insulative body, preferably of a high'temperature insulation, is molded on or otherwise affixed to at least a portion of the outer surface of the bussing ring and extends to two or more of the second contacts of the interconnected connectors.
A thin metallic coating is adherently affixed to at least a portion of the insulative body and serves to interconnect the second contact of two or more connectors. The metallic coating is usually about 100-200 X 10 inches although it may range up to about 1 X 10 inches in thickness and can include two or more layers of shielding metal such as nickel and gold which in combination are capable of withstanding temperatures of about 400500F. without separation from the insulative body and without silver migration at the high temperatures.
In more detail, the module comprises a plurality of the two-contact connectors arranged around a bus ring to form an outer connector assembly having a hollow interior and a plurality of other connectors on an inner bus ring to form an inner connector assembly. An insulative body composed of a high temperature plastic, preferably of one piece, is molded on the outer surface of the outer bus ring and extends over a portion of a centrally located contact in the two-contact connector. The metallic coating is formed over at least a portion of the insulative body and serves to interconnect outer or second contacts in the two-contact connector.
The module 10, illustrated in FIGS. l-5, includes outer connector ring assembly 11 positioned around inner connector assembly 12, offset connectors 14 and 16, and spacers l8 and 20, with the combination being housed between front insert 22 and rear insert 24. In turn, inserts 22 and 24 are housed within an exterior metal shell 26 of aluminum, illustrated in FIG. 4, and provided withvexterior threaded portion 28 for connection to suitable rear housing and complimentary connectors (not shown) to those connectors rearwardly directed in module 10. Exterior metal shell 26 is also provided with interior radial grooves 30 and 31 for gasket 32 and retainer ring 33 which act with gasket 34 to secure module 10 within shell 26 and to keep inserts 22 and 24 in snug engagement. An exterior radial rib 36 is provided on the front end 37 of shell 26 forengagement with a suitable hermetically-sealed module (not shown) mounted on the wall of an aircraft fuel tank or other liquid container.
Included in outer connector assembly 11 are outer ring 38, a plurality of forwardly disposed, closely positioned connectors 39 arranged on the front surface 40 of ring 38 to form hollow interior 41, and one or more rearwardly disposed connectors 42 extending rearwardly from rear 43 of hollow interior 41 and in juxtaposition with rear surface 44 of ring 38. Connecting plate 45 (as illustrated in FIG. 2) serves to interconnect outer ring 38 to rear connector 42 although in some arrangements, connector 42 can be conveniently connected directly to rear surface 44. As illustrated, outer ring 38 includes cutout portion 46 so that one or more of front connectors 39' can be interconnected to one or more rear connectors 42 by connecting plate 47 or other suitable means without being bussed by ring 38.
Each of the connectors 39 and 42 is constructed of beryllium copper and includes an inner, centrally-- located, protected contact 48 and outer, surrounding, protective contact 49 on connectors 39 and similar inner and outer contacts 50 and 51 on connectors 42. Although illustrated in the form of a socket, the inner contact 48 can be shaped as a pin or other form of Iongitudinally extending contact. Outer contact 49 is disposed around socket 48 as a second wire and includes shoulder 52 with front surface 53 which, as illustrated in FIG. 4, acts as a stop for front insert 22.
Thus, each of the forwardly and rearwardly directed inner contacts 48 and 50 are provided with individual shields 49 and 51 against magnetic and electrical fields from external sources as well as from adjacent contacts. In addition, as discussed in more detail below, connectors 39 are arranged around hollow interior 41 to provide a shielding effect in respect to inner connector assembly 12 and offset connectors 14 and 16.
Together'with connecting plates 45 and 47, outer bus ring 38 serves as a means for interconnecting contact 48 with one or more other contacts 48 or contacts 50 or combination thereof. As illustrated, 12 parallel front connectors 39 are arranged in juxtaposition with bus ring 38, with eleven connectors being connected to ring 38 and thereby bussed down to one rear connector 42. The remaining front connector 39 is interconnected by plate 47 to rear connector 42'. In a similar manner, bus ring 38 can be formed with more than one cutout portion 46 to provide two or more bus bars for interconnecting a number of individual groups of connectors 39 and 42.
Outer bus ring 38 is of brass construction and is provided with outer surface 54 and an insulative body 55 of high-temperature insulation capable of withstanding temperatures in the order of 400-500F. such as an aromatic polysulfone affixed to at least a portion of surface 54 and extends to two or more of the outer contacts of connectors 39 and 42 interconnected by bus ring 38. Preferably, insulative body 55 extends to all of contacts 49 and 51 on outer connector assembly 11.
In FIG. 3, a cross-sectional view of individual twocontact connector 39 illustrates the manner in which insulative body 55 is affixed on outer surface 54 of ring 38 and extends under and provides support for contact 49. Advantageously, body 55 extends longitudinally with section 56 in juxtaposition with contacts 48 and 49 to insulatively separate and seal the two contacts near bus ring 38. Inner radial grooves 57 and 58 are provided in contact 49 for sealing and mounting purposes. These and other features of the individual connectors 39 and 42 are described in my copending application Ser. No. 177,730 entitled ELECTRICAL CONNEC- TOR and filed Sept. 3, I971 which is incorporated herein by reference.
In forming the outer connector assembly 11, a plurality of two-contact connectors 39 and 42 without insulative body 55 are positioned around ring 38 to form hollow interior 41. Inner contacts 48 are swaged or otherwise forced into abutting engagement in apertures 59 in brass bus ring 38 and connecting plates 45 and 47 are interconnected to bus ring 38 and contact 50. A moldable high-temperature plastic, and preferably an aromatic polysulfone, is transferred into the mold and forced between contacts 48 and 49 and contacts 50 and 51 as well as around surfaces 54 and 60 of ring 38 and plates 45 and 47. After the insulated assembly is removed from the mold, openings 106-107 resulting from mold supporting surfaces are filled with the plastic forming plugs 108-109.
In the preferred embodiment, the aromatic polysulfone is of the type available from Minnesota Mining & Manufacturing as generally described on page 182 of Modern Plastics Encyclopedia, 1970-1971 and has only aromatic groups as the organic portion of the polymer. This polymer provides a combination of hightemperature properties, dimensional stability, sealing characteristics, and platability particularly important for the high-temperature connector. Mixtures of the aromatic polysulfone with other high-temperature plastics such as Teflon can also be utilized for the insulative body.
Next, metallic coating 62 is adherently affixed to outer surface 63 of insulative body 55 and serves to interconnect two or more contacts 49 and 51. Since insulative body 55 extends over bus ring 38, metallic coating 62 provides a shield over bus ring 38 without electrically interferring with the internal bussing provided thereby.
Metallic coating 62 is composed of one or more metals which are capable of withstanding temperatures of about 400-500F. without separation from the underlying insulative body 55, without flaking associated with silver migration at these temperatures, and without excessive corrosive effects. Advantageously, the coating includes an outer corrosion resistant metallic layer such as gold, nickel or the like and includes metallic shields for magnetic and electrical fields of nickel and gold, copper and nickel, iron and gold, and the like. In the preferred embodiment with an aromatic polysulfone, coating 62 is composed of nickel inner layer 65 on body 55 and a gold outer layer 66 on at least a portion of the nickel inner layer. The nickel and gold layers 65 and 66 act in combination as a shield against both magnetic and electrical fields. In contrast, tests with a coating composed of copper, silver and gold revealed that at the high temperatures, portions of the coating could easily be manually removed.
Advantageously, coating 62 extends over a portion of contacts 49 and 51 and in the preferred embodiment, over the entire surface 67 of the contacts. In the process of forming coating 62, surfaces 63 and 67 of insulative body 55 and contact 49 are treated to adapt them to adherently receive one or more layers of a metal. Treatment can include the use of an adhesive on surface 63 and separate coating steps on plastic surface 63 and metal surface 67. In the preferred embodiment, plastic surface 63 is treated to receive electrolessly deposited metal and a nickel layer is deposited in this manner over surface 63 as well as over at least a portion of metallic surface 67. The gold is then electroplated over the nickel inner layer. To avoid coating contact 48, a plug (not shown) is first inserted around contact 48 and surface 68 of the body 55. As an alternative, contact 49 (illustrated in FIG. 6) can be formed by extending metal coating 62 over body 55 surrounding contact 48. In this instance, body 55 is extended as a plastic sleeve 69 spacially surrounding and separated from contact 48 to form a socket and in juxtaposition with coating 62 which forms a metallic sleeve to serve as the outer contact 49.
Disposed within an outer connector assembly 11 is inner connector assembly 12, offset connectors 14 and 16 and spacers 18 and 20 (of aromatic polysulfone). Connector assembly 12 comprises a plurality of forwardly disposed connectors 70, inner bus ring 71, and one or more rearwardly disposed connectors 72. In the preferred embodiment, ten single-contact front connectors 70 extend frontwardly from front surface 73 of bus ring 71 and are bussed thereby to rear singlecontact connector 72 extending from rear surface 74 of ring 71. One or more cutout portions 75 in ring 71 permit the extension of separate single-contact front connector 76 Of offset connector 14 while hollow interior 77 of ring assembly 12 provides a passage for singlecontact front connector 78 of offset connector 16. As illustrated, offset connectors 14 and 16 include flat bars 79 and 80 for interconnecting front and rear connectors 76 and 81 and 78 and 82 respectively and serve to mount connectors 14 and 16 in cavities 83 and 84 of spacer 18 in an arrangement which resists axial and lateral movement.
Spacer 18 also includes apertures 85, 86, and 87 which serve as passages for rear connectors 72, 81, and 82 of inner bus ring assembly 12 and offset connectors 14 and 16. Spacer 18 is a disc-like polygon with outer concave surfaces 88 to resist radial movement in respect to outer bus ring assembly 11.
Cavity 89 in spacer 20 serves to position and insulate inner bus ring assembly 12 from the other metallic components in assembly 10. Apertures 90, 91, and 92 are provided as passages for rear connector 72 and front connectors 76 and 78 of offset connectors 14 and 16. Spacer 20 is also shaped as a disc-like polygon with concave surfaces 93 for resisting radial movement in assembly 10.
In forming assembly 10, outer connector assembly 11 is placed around the combination of spacer 18, offset connectors 14 and 16, spacer 20 and inner connector assembly 12. Front and rear inserts 22 and 24 (of aromatic polysulfone) are then positioned on and around outer assembly 11. Apertures 95 and 96 of front insert 22 are adapted to respectively receive 12 two-contact front connectors 39 of assembly 11 and 12 singlecontact connectors 70, 76, and 78 of assembly 12 and offset connectors 14 and 16. Similarly, rear insert 24 includes apertures 97 and 98 to receive 2 two-contact connectors 42 of assembly 11 and 3 single-member rear connectors 72, 81, and 82 of assembly 12 and connectors 14 and 16. The entire combination, as illustrated in FIG. 4, is then housed in shell 26.
IN FIG. 4, a cross-sectional view of the internal bussing arrangement is illustrated and depicts the arrangement by which 12 two-contact connectors are internally reduced to 2 connectors and 12 single-contact connectors are internally reduced to 3 connectors. As illustrated, front connectors 39 extend through apertures 95 of front insert 22 and are internally bussed by outer bus ring 38 to rear connectors 42. In a similar manner, connectors 70 extend through apertures 96 and front insert 22 and are internally interconnected by inner bus ring 71 to rear connectors 72. Spacers 18 and 20 serve as means for mounting offset connectors 14 and 16 and insulatively separating these connectors from outer assembly 11 and inner assembly 12. As illustrated, (FIG. 1) cavities 83-84 and 89 are respectively formed in spacers l8 and 20 and are separated by spacer 20. Spacer 18 is also provided on its rear surface 99 with rearwardly extending surfaces 100 and 101 (FIG. 4) for positioning of the spacer in rear insert 24. Rear insert 24 is also provided with forward extension 102 which fits in complimentary groove 103 in outer assembly 11 and spacer 18.
FIG. 5 further illustrates the relative positions of front connectors 39, 70, and 76, and 78. The front view of exterior shell 26 is also illustrated together with the projections 104 and 105 for keying assembly in shell 26 and for a mating housing (not shown) containing complimentary connectors into shell 26. Cutaway portions of the assembly 10 also reveal flat bars 79 and 80 of offset connectors 14 and 16 within the assembly.
The foregoing description of the present invention is only illustrative of an exemplary form which the invention may take. Still other modifications and variations will suggest themselves to persons skilled in the art. It is intended, therefore, that the foregoing detailed description be considered as exemplary only and that the scope of the invention be ascertained from the following claims.
What is claimed is:
1. A multi-connector module comprising at least one forwardly disposed two-contact connector, at least one other two-contact connector in juxtaposition with said forwardly disposed connector, each connector having first and second contacts being insulatively separated and each adapted for connection to an external con- 'ductor, means for interconnecting said first contact of at least two of said connectors, said means having an outer surface, a high temperature insulative body affixed to at least a portion of said outer surface and extending to at least two of said second contacts of said interconnected connectors, and a metallic coating adherently affixed to at least a portion of said insulative body and interconnecting said second contacts said insulative body and said metallic coating remaining intact and adherently affixed at temperatures of about 400-S00F.
2. The multi-connector module of claim 1 wherein said insulative body is of one-piece thermoplastic and said metallic coating remains affixed to said insulative body attemperatures of about 400-500F.
3. The multi-connector module of claim 2 wherein said plastic is an aromatic polysulfone and said coating is a nickel inner layer on said plastic and a gold outer layer on at least a portion of the inner layer.
4. The multi-connector module of claim 1 wherein said insulative body extends under and provides support for at least a portion of said second contact.
5. The multi-connector module of claim 4 wherein said second contact is an extension of said metallic coating.
6. The multi-connector module of claim ll wherein a plurality of said forwardly disposed two-contact connectors are arranged in a parallel pattern, said pattern forming and surrounding a hollow interior, said insulative body extends on said second contacts around said hollow interior, and said metallic coating is affixed over said insulative body and electrically shields said hollow interior.
7. The multi-connector module of claim 6 which includes an inner connector assembly disposed within said hollow interior, shielded by said metallic coating and insulatively separated from said two-contact connectors.
8. The multi-connector module of claim 6 wherein said insulative body is of one-piece insulative thermoplastic capable of withstanding temperatures of about 400500F. without deformation and said metal coating includes a nickel inner layer and a gold outer layer on at least a portion of said inner layer.
9. The connector assembly of claim 6 wherein said interconnecting means is a metallic ring interposed between at least a portion of said forwardly disposed and said rearwardly disposed connectors.
10. A multi-connector module comprising an outer connector assembly including an outer metallic bus ring having front and rearsurfaces, a plurality of connectors frontwardly disposed around at least a portion of the front surface of said ring, each of said connectors including first and second contacts, said ring being connected to at least a portion of said first contacts, at least one other connector including first and second contacts connected to the rear surface of said ring by said first contact and extending rearwardly therefrom, each of said second contacts including a metallic sleeve coaxially disposed around each of at least a portion of said frontwardly and rearwardly disposed first contacts and insulatively separated from said ring, an insulative body disposed on said ring and including a section insulatively separating a portion of each first contact from its associated metallic sleeve, said-insulative body having an outer surface, a metallic layer affixed to at least a portion of said outer surface of said insulative body and at least a portion of said metallic sleeves including those of at least two of said frontwardly disposed connectors to electrically interconnect said metallic sleeves, said interconnected metallic sleeves on said frontwardly disposed connectors being in juxtaposition on said front surface of said ring to form a hollow interior, and an inner connector assembly comprising an inner bus ring disposed within said hollow interior and insulatively separated from said outer ring, connectors, and metallic coating, said inner ring having front and rear surfaces, a plurality of forwardly disposed connectors affixed to the front surface of said inner ring, and at least one rearwardly disposed connector extending rearwardly from said ring.
11. The multi-connector module of claim 10 wherein at least one of said forwardly disposed connectors is insulatively separated from said outer bus ring and at least one rearwardly disposed connector is interconnected to said insulatively separated connector.
12. The multi-connector module of claim 10 wherein the metallic coating is an inner layer of nickel and outer layer of gold on at least a portion of said inner layer.
13. The multi-connector module of claim 12 wherein said insulative body is composed of an aromatic polysulfone.
14. The multi-connector module of claim 10 wherein the section of said insulative body which insulatively separates a portion of said first contact and metallic sleeve includes an insulative sleeve in juxtaposition with said metallic sleeve.
rearwardly disposed connectors and a second insulativc spacer having a front surface bearing against the rear surface of said inner ring, each of said pair of connectors including a positioning section between and separating said first and second spacers.
18. The multi-connector module of claim 15 which includes a frontwardly positioned insert having apertures in registered alignment with said metallic sleeves, said forwardly disposed connectors on said inner ring, and said forwardly disposed contact on said pair of connectors.