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//-->Ignition TechnologyDiesel Cold-Start TechnologyCoolingSensorsAll about ignition coilsTechnicalInformationNo. 07®Perfectionbuilt in2Table of ContentsIntroductionThe spark-ignition engineOperation of ignition coils in the spark-ignition engineDemands on modern ignition coils3445Ignition coils –design and mode of operationIgnition technology terminologyHow many ignition sparks does an engine need?Ignition coil specifications / characteristics5677Ignition coils –types and systemsCanister-type ignition coilsElectronic distributor ignition coilsDouble-spark ignition coilsIgnition coil railsPlug shaft / plug / smart plug top coil ignition coilsDual coil ignition coils8899111113Ignition coil – productionStep-by-step to a precision productTested qualityThe genuine article and fakes14141515Workshop tipsReasons for replacementProfessional removal / installationSpecial tool for ignition coil replacementTesting and checkingStep-by-step defect identification171718182021Self-test223IntroductionFewer emissions, lower fuel consumption, higherignition voltage, restricted space in the drive unit andengine compartment: The design demands on modernignition coils are constantly increasing. Although thetask of spark-ignition engines remains the same: thefuel / air mixture must be ignited at the right time withthe optimum ignition energy so that complete combusti-on occurs. To reduce fuel consumption and emissionsand to increase the efficiency, engine technologies areconstantly developed further – and thus also the BERUignition systems.In particular, the company runs its own R&D departmentsat its Ludwigsburg, Germany headquarters and in Asia,in which ignition technologies are driven forward incooperation with the international automotive industry.Thus BERU ignition coils are being precisely adapted tothe requirements of modern spark-ignition engines suchas turbocharging, downsizing, direct injection, lean mix,high exhaust gas recirculation rates etc. In the process,the company is able to fall back on a whole century ofvaluable experience as an ignition technology expert.BERU ignition coils are produced in state-of-the-artfacilities at its own production plants in Ludwigsburgand Muggendorf, Germany, as well as in Asia. BERUsupplies OEM's with ignition coils for nearly all signi-ficant European volume applications. The companycurrently offers a range of over 400 ignition coils to themaintenance and repair markets – needless to say inoriginal equipment quality. Today the market penetrationof the range in VW vehicles is 99%, in BMW Groupvehicles 80%, in the VW Group as a whole 95% – andtoday the range is being continuously extended inaccordance with market requirements.4The spark-ignition engineOperation of ignition coils in the spark-ignition engineOptimum ignition of the compressed fuel / air mixture has beenone of the greatest challenges for designers since the early daysof engine construction. In the case of ignited sparked engines,this conventionally occurs in sequence with the compression cycleby an electrical spark from the spark plug. So that the voltagecan make the jump between the electrodes, a charge must firstbe accumulated by the vehicles' low voltage electrical system,then stored and finally discharged at the spark plug at the ignitiontiming. This is the job of the ignition coil as an integral part of theignition system.An ignition coil must be exactly attuned to the respective ignitionsystem. The required parameters include:The spark energy, which is available to the spark plugThe spark current at the time of the spark dischargeThe combustion duration of the spark at the ignition plugThe ignition voltage under all operating conditionsThe spark count at all speedsSpark-ignition engines with turbocharger or direct fuel injectionrequire higher spark energies. The high voltage connectionbetween ignition coil and spark plug must be functional and safe.This is where BERU comes in with high-quality ignition cableswith suitable contacts or high-voltage ignition coil connectors.5Demands on modern ignition coilsIgnition coils in the ignition systems of modern cars generatevoltages of up to 45,000 V. It is essential that misfiring – and asa consequence incomplete combustion – is avoided. It is notonly that the vehicles' catalytic converter could be damaged.Incomplete combustion also increases emissions and thus envi-ronmental pollution.Ignition coils are – regardless of the system (static high voltagedistribution, rotating high voltage distribution, double spark coil,single spark coil) – electrically, mechanically and chemicallyhighly stressed components of the spark-ignition engines. Theymust perform faultlessly under a wide variety of installation con-ditions (on the body, engine block or directly on the spark plug inthe cylinder head) over a long service life.Plug shaft ignition coils are mounteddeep in the engine compartmentand must withstand extreme thermalloads.Ignition coils: electrical, mechanical, thermal,electrochemical requirementsTemperature range -40 °C to +180 °CSecondary voltage to 45,000 VPrimary current 6 to 20 ASpark energy 10 mJ up to approx. 100 mJ (at present)or 200 mJ (future)Vibration range to 55 gResistance to gasoline, oil, brake fluidIgnition coils – design and mode of operationIgnition coils work on the transformer principle. They basi-cally consist of a primary winding, a secondary winding, theiron core and a housing with isolation material, nowadaystwo-component epoxy resin.On the iron core of individual thin steel sheets two coilelements are applied e.g.:The primary winding is made of thick copper wire withapprox. 200 windings (diameter approx. 0.75 mm²),The secondary winding is made of thin copper wire withapprox. 20,000 windings (diameter approx. 0.063 mm²) [ Pobierz całość w formacie PDF ]