# US 4,398,779 A · Keying apparatus for interconnecting electrical components > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,398,779 A - Document ID: US4398779A - Status: Granted - Kind: A - Application number: 06/217,708 - Filed: 1980-12-18 - Granted: 1983-08-16 - Earliest claimed: 1980-12-18 - Assignees: Bell Telephone Laboratories, Incorporated - Inventors: Dean D. Ling - Web page: https://patentgrep.com/patent/US4398779A ## CPC - H01R 13/645: by exchangeable elements on case or base - H01R 12/712: {co-operating with the surface of the printed circuit or with a coupling device exclusively provided on the surface of the printed circuit (H01R12/72 takes precedence)} - H01R: ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS ## Abstract Apparatus for ensuring the proper interconnection of an electrical component (11) and the terminal pins (15) of a backplane (10). A keying member (14) having a pair of dowels (26, 27) at a predetermined spacing uniquely selected from a plurality of possible spacings (a.sub.1 -a.sub.4 ; b.sub.1 -b.sub.4) is associated with an array of pins (15) to which connection is to be made. The component (11) presents a vertical plate, the leading edge of which is notched (40, 42) to correspond to the dowel spacing so that, as the component is fitted to the pin array, the dowels (26, 27) freely enter the notches (40, 42). A connector block (34) and a stiffener member (38) on opposite sides of the plate are fluted (43, 44) to correspond to the plurality of possible spacings and to present possible cylindrical holes thereat, completed cylindrical holes being presented only where the plate is correspondingly notched. Polarization is achieved by avoiding a symmetrical spacing of the dowels along the keying member. ## Claims ### Claim 1 In combination, an electrical component presenting a keying plate on at least one side, said plate having a first and an opposite, second face and a leading edge, and a connector block adapted to engage an array of backplane terminal pins said block having a surface abutting said first keying plate face, said plate having a first and a second notch formed inwardly from said leading edge, said notches being spaced and located at predetermined locations on said plate selected from a plurality of possible fixed locations on said plate, said notches being dimensioned to admit a first and a second dowel correspondingly spaced associated with said array of terminal pins, said surface of said connector block having flutings formed therein dimensioned to admit said dowels, said flutings being spaced to correspond to said plurality of possible fixed locations on said plate. ### Claim 2 (depends on 1) The combination as claimed in claim 1 in which said electrical component comprises an electrical circuit board. ### Claim 3 Electrical interconnection apparatus comprising an array of terminal pins (15), a connector block (34) adapted to fit over said pins (15), and an electrical component (11) presenting a plate leading edge characterized in a keying member (12, 13, 14) associated with said array of terminal pins (15), said member (14) having a pair of dowels (26, 27) extending outwardly therefrom having a predetermined spacing uniquely selected from a plurality of possible spacings, in that said plate leading edge of said component (11) has a pair of notches (40, 42) formed therein spaced apart to correspond to said predetermined spacing of said pair of dowels (26, 27) and dimensioned to admit said last-mentioned dowels when said connector block (34) is fitted over said array of terminal pins (15), and in that said connector block (34) is formed to present a face in contact with one side of said component (11) plate and having a plurality of flutings (43) in said face dimensioned to admit said dowels (26, 27) and spaced to correspond to said plurality of possible spacings. ### Claim 4 (depends on 3) Electrical interconnection apparatus as claimed in claim 3 further characterized in a flat stiffener member (38) having a face in contact with the other side of said component (11) plate and having a plurality of flutings (44) dimensioned to admit said dowels (26, 27) and spaced to correspond to said plurality of possible spacings. ### Claim 5 (depends on 4) Electrical interconnection apparatus as claimed in claim 4 further characterized in that said electrical component (11) comprises an electrical circuit board. ### Claim 6 (depends on 4) Electrical interconnection apparatus as claimed in claim 4 further characterized in that said keying member (12, 13, 14) has an electrically conductive, third dowel (32) extending outwardly therefrom and connected to an additional terminal pin, said face of said connector block (34) has a fluting (47) dimensioned to admit said third dowel (32) and located to correspond to the position of said third dowel (32) and in an electrical contact spring (48) positioned in said last-mentioned fluting (47) to make electrical contact with said third dowel (32) when said connector block (34) is fitted over said array of terminal pins (15). ### Claim 7 Electrical interconnection apparatus comprising an array of terminal pins (15), a connector block (34) adapted to fit over said pins (15), and an electrical component (11) presenting a plate leading edge characterized in a keying member (12, 13, 14) associated with said array of terminal pins (15), said member (14) having a pair of dowels (26, 27) extending outwardly therefrom having a predetermined spacing uniquely selected from a plurality of possible spacings and in that said plate leading edge of said component (11) has a pair of notches (40, 42) formed therein spaced apart to correspond to said predetermined spacing of said pair of dowels (26, 27) and dimensioned to admit said last mentioned dowels when said connector block (34) is fitted over said array of terminal pins (15), and in that said connector block (34) is formed to present a face in contact with one side of said component (11) plate and having a plurality of flutings (43) in said face dimensioned to admit said dowels (26, 27) and spaced to correspond to said plurality of possible spacings, and further characterized in a flat stiffener member (38) having a face in contact with the other side of said component (11) plate and having a plurality of flutings (44) dimensioned to admit said dowels (26, 27) and spaced to correspond to said plurality of possible spacings. ### Claim 8 (depends on 7) Electrical interconnection apparatus as claimed in claim 7 further characterized in that said electrical component (11) comprises an electrical circuit board. ### Claim 9 (depends on 7) Electrical interconnection apparatus as claimed in claim 7 further characterized in that said keying member (12, 13, 14) has an electrically conductive, third dowel (32) extending outwardly therefrom and connected to an additional terminal pin, said face of said connector block (34) has a fluting (47) dimensioned to admit said third dowel (32) and located to correspond to the position of said third dowel (32) and in an electrical contact spring (48) positioned in said last-mentioned fluting (47) to make electrical contact with said third dowel (32) when said connector block (34) is fitted over said array of terminal pins (15). ### Claim 10 In combination, an electrical component presenting a keying plate on at least one side, said plate having a first and an opposite, second face and leading edge, a connector block adapted to engage an array of backplane terminal pins, said block having a surface abutting said first keying plate face, and a stiffener plate having a surface abutting said opposite second face of said keying plate, said keying plate having a first and a second notch formed inwardly from said leading edge, said notches being spaced and located at predetermined locations on said keying plate selected from a plurality of possible fixed locations of said keying plate, said notches being dimensioned to admit a first and a second dowel correspondingly spaced associated with said array of terminal pins, said surface of said connector block having flutings formed therein dimensioned to admit said dowels, said flutings being spaced to correspond to said plurality of possible fixed locations on said keying plate, said surface of said stiffener plate having flutings formed therein dimensioned to admit said dowels and spaced to correspond to the spacings of said flutings on said surface of said connector block. ### Claim 11 (depends on 10) The combination as claimed in claim 10 in which said electrical component comprises an electrical circuit board.