# US 2014/0209076 A1 · Ignition plug and method for the ignition of a fuel-air mixture by means of an ignition plug of said type > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0209076 A1 - Document ID: US20140209076A1 - Status: Published application - Kind: A1 - Application number: 14/156,288 - Filed: 2014-01-15 - Published: 2014-07-31 - Earliest claimed: 2013-01-25 - Assignees: Ford Global Technologies, LLC - Applicants: Ford Global Technologies, LLC - Inventors: Oliver Berkemeier; Klemens Grieser - Web page: https://patentgrep.com/patent/US20140209076A1 ## CPC - H01T 13/26: for adjusting spark gap otherwise than by bending of electrode - F02P 9/002: {Control of spark intensity, intensifying, lengthening, suppression (by means of current control in the storage devices F02P3/05, F02P3/09, during starting F02P15/12)} - F02P 17/12: Testing characteristics of the spark, ignition voltage or current (testing of sparking plugs H01T13/60) - H01T: SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES (overvoltage protection circuits H02H) - F02P: IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES ({anti-pollution means for internal-combustion engines F02B17/00}; specially adapted for rotary-piston or oscillating-piston engines F02B53/12; {ignition of gas turbine plants F02C7/26; ignition of jet propulsion plants F02K9/95; starting of combustion engines F02N9/00}; ignition of combustion apparatus in general, glowing plugs F23Q; measuring of physical variables in general G01; controlling in general G05; data processing in general G06; electrical components in general see Section H; {ignition coils H01F38/12}; sparking plugs H01T13/00) ## Abstract An adjustable ignition plug, with one or more variable electrodes, and a method to adjust the electrode gap spacing based on various engine operating parameters. This better enables the reliable ignition of the air-fuel mixture in a cylinder of a direct-injection internal combustion engine under various engine operating conditions. ## Claims ### Claim 1 An ignition plug for igniting a fuel-air mixture in a cylinder of a direct-injection, applied-ignition internal combustion engine, comprising: an ignition plug has at least one electrode pair which comprises a two electrodes which are electrically insulated with respect to and spaced apart from one another, of which a first electrode serves as a ground electrode, a spacing between the first electrode and a second electrode in an ignition gap, in which a spark path forms during a course of an applied ignition, being variable, wherein at least one of the two electrodes is designed to be movable for the purpose of adjustment of the spacing in the ignition gap, for which purpose an adjustment device is provided. ### Claim 2 (depends on 1) The ignition plug as claimed in claim 1, wherein the at least one electrode that is designed to be movable is the ground electrode. ### Claim 3 (depends on 1) The ignition plug as claimed in claim 1, wherein both electrodes of the electrode pair are designed to be movable. ### Claim 4 (depends on 1) The ignition plug as claimed in claim 1, wherein a central electrode is provided which is arranged in a housing of the ignition plug and which is electrically insulated from the ground electrode by means of an insulator. ### Claim 5 (depends on 4) The ignition plug as claimed in claim 4, wherein the central electrode is the at least one electrode that is designed to be movable, the ground electrode being designed to be immovable. ### Claim 6 (depends on 5) The ignition plug as claimed in claim 5, wherein the central electrode is displaceable in translatory fashion in a housing by means of an adjustment device, the ground electrode being rigidly connected to the housing. ### Claim 7 (depends on 1) The ignition plug as claimed in claim 1, wherein the adjustment device comprises at least one temperature-reactive wax element whose volume changes as a function of temperature, the change in volume of the wax element leading to a movement of the at least one electrode that is designed to be movable. ### Claim 8 (depends on 7) The ignition plug as claimed in claim 7, wherein the at least one temperature-reactive wax element is arranged in a working chamber and, when activated by means of an increase in temperature, actuates a displacement mechanism which effects a movement of the at least one electrode that is designed to be movable. ### Claim 9 (depends on 8) The ignition plug as claimed in claim 8, wherein the temperature-reactive wax element, when activated by means of an increase in temperature, effects a reduction of the spacing in an ignition gap as a result of a movement of the at least one electrode that is designed to be movable. ### Claim 10 (depends on 7) The ignition plug as claimed in claim 7, wherein the temperature-reactive wax element is actively controllable. ### Claim 11 (depends on 10) The ignition plug as claimed in claim 10, wherein the temperature-reactive wax element is actively controllable by means of a heating element and/or an engine controller. ### Claim 12 An engine control method, comprising: adjusting a spacing between a first electrode and a second electrode of an ignition plug via code stored in memory of controller. ### Claim 13 (depends on 12) A method as claimed in claim 12 wherein the spacing is adjusted by the controller responsive to at least one operating parameter of the engine, wherein the spacing is set variably during engine operation while the engine carries out combustion. ### Claim 14 (depends on 13) The method of claim 13 further wherein the spacing is increased with an increased exhaust gas recirculation rate. ### Claim 15 (depends on 13) A method as claimed in claim 13 wherein the spacing is increased in response to an increased plug age, the plug age determined by the controller based on a number of engine hours, vehicle miles, or combinations thereof. ### Claim 16 (depends on 13) A method as claimed in claim 13 wherein the spacing is further adjusted based on engine temperature. ### Claim 17 (depends on 13) A method as claimed in claim 13 wherein the spacing is increased responsive to an air-fuel ratio in a cylinder being leaner than a lean threshold. ### Claim 18 (depends on 13) A method as claimed in claim 13 further comprising adjusting the spacing responsive to an ignition voltage. ### Claim 19 (depends on 13) A method as claimed in claim 13 further comprising adjusting the spacing responsive to an engine load.