# US 8,569,658 B2 · Composite conductor, in particular for glow plugs for diesel engines > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,569,658 B2 - Document ID: US8569658B2 - Status: Granted - Kind: B2 - Application number: 11/992,395 - Filed: 2006-09-21 - Published: 2010-01-07 - Granted: 2013-10-29 - Earliest claimed: 2005-09-22 - Assignees: Beru AG - Applicants: Martin Allgaier; Hans Peter Kasimirski; Rainer Hain; Bernhard Graf; Oliver Göb; Lutz Frassek; Johannes Hasenkamp; Jochen Hammer; Henning Von Watzdorf; Hans Houben - Inventors: Martin Allgaier; Hans Peter Kasimirski; Rainer Hain; Bernhard Graf; Oliver Göb; Lutz Frassek; Johannes Hasenkamp; Jochen Hammer; Henning Von Watzdorf; Hans Houben - Web page: https://patentgrep.com/patent/US8569658B2 ## CPC - F23Q 7/001: {Glowing plugs for internal-combustion engines} - Y10T 29/49117: Conductor or circuit manufacturing - F23Q: IGNITION (devices or installations peculiar to internal-combustion engines F02P; of cigarettes or tobacco A24F; compositions therefor, chemical igniters C06C); EXTINGUISHING-DEVICES - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Composite conductor comprising a metallic conductor and a ceramic conductor or non-conductor, at least one of them being elongate, the two being connected with each other in an electrically conductive manner. The ceramic conductor or non-conductor and the metallic conductor are hard-soldered to each other by a contact surface extending obliquely to the longitudinal direction of the at least one elongate conductor, and has one of the conductors tapers at its end and the other conductor has a matching tapering recess. The tapering end of the conductor is fitted into the tapering recess. ## Claims ### Claim 1 Composite electric conductor comprising: an elongate ceramic inner conductor; an elongate ceramic outer conductor enclosing the ceramic inner conductor, and an insulator arranged between the ceramic inner conductor and the ceramic outer conductor; an elongate metallic inner conductor which is connected to the ceramic inner conductor in an electrically conductive manner; and an elongate metallic outer conductor which is connected to the ceramic outer conductor in an electrically conductive manner, wherein both of the ceramic conductors and their corresponding metallic conductors are fitted one in the other and make contact primarily via a lateral surface extending obliquely to their longitudinal direction and via an oppositely arranged inner surface, said surfaces being hard-soldered one to the other. ### Claim 2 (depends on 1) Conductor according to claim 1, wherein the metallic outer conductor encloses the metallic inner conductor. ### Claim 3 (depends on 1) Conductor according to claim 1, wherein the inner conductors and the outer conductors are arranged coaxially one relative to the other. ### Claim 4 (depends on 1) Conductor according to claim 1, wherein the contact-making lateral surfaces are frustum-shaped surfaces. ### Claim 5 (depends on 1) Conductor according to claim 1, wherein the ceramic inner conductor has a frustum-shaped inner surface which transitions to a cylindrical blind hole. ### Claim 6 (depends on 1) Conductor according to claim 1, wherein the insulator, separating the ceramic inner conductor from the ceramic outer conductor, has a blunt end face. ### Claim 7 (depends on 1) Conductor according to claim 1, wherein the metallic inner conductor has a neck in the neighborhood of the point of connection to the ceramic inner conductor. ### Claim 8 (depends on 1) Conductor according to claim 1, wherein an annular insulator is only in some places in an annular gap between the metallic outer conductor and the metallic inner conductor. ### Claim 9 (depends on 1) Conductor according to claim 1, wherein it is designed as a glow plug for a diesel engine. ### Claim 10 (depends on 9) Conductor according to claim 9 comprising a metallic housing, which is the metallic outer conductor or part of the metallic outer conductor. ### Claim 11 (depends on 10) Conductor according to claim 10, wherein a metallic sleeve, being part of the outer conductor is fitted in a forward end of the metallic housing which faces in use the combustion chamber of a diesel engine. ### Claim 12 (depends on 11) Glow plug according to claim 11, wherein the metallic sleeve is pressed into the metallic housing from the forward end. ### Claim 13 (depends on 11) Conductor according to claim 11, wherein the sleeve projects beyond the forward end of the metallic housing. ### Claim 14 (depends on 11) Conductor according to claim 11, wherein the ceramic inner conductor and the ceramic outer conductor project beyond the forward end of the metallic sleeve and are connected one to the other at their tips by a ceramic heating element. ### Claim 15 (depends on 11) Conductor according to claim 11, wherein the metallic housing is subdivided in trans-verse direction. ### Claim 16 (depends on 15) Conductor according to claim 15, wherein the metallic housing is subdivided in the neighborhood of an annular insulator. ### Claim 17 (depends on 15) Conductor according to claim 15, wherein the metallic inner conductor is subdivided in transverse direction. ### Claim 18 (depends on 17) Conductor according to claim 17, wherein the areas where the metallic inner conductor and the metallic housing are subdivided in transverse direction are positioned close to each other. ### Claim 19 Composite electric conductor comprising: an elongate ceramic inner conductor; an elongate ceramic outer conductor enclosing the ceramic inner conductor, and an insulator arranged between the ceramic inner conductor and the ceramic outer conductor; an elongate metallic inner conductor which is connected to the ceramic inner conductor in an electrically conductive manner; and an elongate metallic outer conductor which is connected to the ceramic outer conductor in an electrically conductive manner, wherein both of the ceramic conductors and their corresponding metallic conductors are fitted one in the other and make contact primarily via a common lateral surface extending obliquely to their longitudinal direction and via an oppositely arranged inner surface, said surfaces being hard-soldered one to the other.