DE2734034A1 - IGNITION SYSTEM - Google Patents

Description

COHAUSZ & FLORACK

I ¹ ATN NTANWA 1, THHf) HO l) -4 HÜBHKl.DOIir. 8 (! ΙΙΓΜΛΝΝϊϊΤΙΙ. 117 2 7 3 A 0 3 A

PATf NT ANWAIl Γ Dipl. Ing W COHAUSZ Dipl Ing W FIORACK Dipl ing R KNAUF Di Ing D. ,, 1 Wnu.h In ₉ A GIRBIR [> ψΙ Im, HB COHAUSZ

ERIC H * FORD RESEARCH AHD DEVELOPMENT LIMITED 77- ^ 51 Hev / iivjton Causeway

CD-London July 27th 1977

Zündun / -; sanlar, e The invention relates to an ignition system.

Eg it is known that from the 3eirundärwindung of the ignition coil Energy with high voltage, but with comparatively less Amperage is supplied. En int a characteristic of spark plugs that they carry a much higher voltage Achieving the initial ionization; need the electrodon gap, Aln never to maintain the current flow across the gap, naclidem the ionization has taken place. This difference bdrä ^ t /; rob 6,000 Volts up to 3,000 volts with a warning engine, but it can go up to 17,000 volts to 1,000 volts with a cold engine increase.

Because modern burners cn ma; ercre mixtures for large ones Ignition ^ advance angles must burn to low [; e The standard ignition coil is to create emission values no longer able to achieve the high ignition energy supply, which is necessary for these operating conditions.

The invention is therefore based on the object of the above To partially or completely eliminate the disadvantage.

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According to the invention an ignition system is provided which has two coils, the secondary windings of the two ignition coils being connected so that the same spark plug or energy is supplied to the same distribution system.

The two coils are preferably arranged so that one coil always ionizes the gap before the other does.

In a preferred embodiment, a first coil starts supplying voltage before the other coil.

In a second preferred embodiment, the two coils start supplying voltage simultaneously.

In the first case, the two primary windings of the ignition coils are triggered by respective bistable optoelectronic triggers on and off, one of which is designed to work shortly before the other. With this arrangement the energy delivered by the first secondary ionizes the gap on the spark plug, and then both deliver Selaindarwicklungs ignition energy at the same time for the Duration of 2-3 milliseconds after the ignition gap has been ionized once with the second secondary winding Provides most of the energy needed to maintain the spark after the gap once has been ionized.

In the second case there are two possible arrangements for supplying power from the two ignition coils. For the first the ignition coils are both operated by the same bistable optoelectronic trigger, and the coils have that same turns ratio so that after one coil has ionized the gap, both supply energy at the same time. Second, the ignition coils, which in turn are both operated by the same trigger, have different windings.

709886/0761

ratio, and delay means are in the secondary circuit of the coil provided, which has the faster secondary voltage rise time so that once the other coil has ionized the gap, both coils have their energy simultaneously deliver.

The secondary windings preferably each discharge their energy through a respective diode. In the latter Arrangement is preferably a capacitor with the connection between a diode and the secondary winding, which is the higher Has rise time, and connected to ground, the capacitor forming the delay means.

The invention is explained in more detail below on the basis of exemplary embodiments with reference to the drawings. In the drawings are:

Pig. 1 shows a circuit diagram of a preferred embodiment of a double ignition coil system using two optoelectronic Trigger to deliver high ignition energy to an internal combustion engine that is running with a lean Fuel mixture is operated,

Figure 2 is a circuit diagram of another preferred embodiment of a double ignition coil system using a single optoelectronic trigger, with the delay means to increase the secondary voltage rise time the coil with the lower turns ratio are provided, and

Pig. 3 is a circuit diagram of a modified version of the double ignition coil system shown in Pig * 2 in which the two coils have the same turns ratio

As shown in Pig * 1, the ignition system has a Ignition coil 1 and an ignition coil 2, each with a primary winding P1 or P2 and a secondary winding S1 or s2.

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The primary windings P1 and P2 are in series with respective power transistors Ϊ1 and Τ2 between the 12 volt battery network of the internal combustion engine switched. The ends of the secondary windings S1 and S2 that are not connected to the primary windings concerned are connected to a distributor Z via respective diodes D1 and D2. The distributor Z distributes the energy to the spark plugs 3 in the correct sequence of the cylinder ignition according to conventional practice.

The power transistors T1 and T2 are turned into bistable by respective "lumenition" triggers (registered trademarks) optoelectronic version switched, consisting of respective trigger modules X1 and X2. The trigger modules X1 and X2 are supplied with power from respective phototransistors B1 and B2 as a result of infrared radiation of respective gallium arsenide lamps A1 and A2 after passage through the holes or slots of respective disks C1 and C2, which run synchronously with the engine.

The primary windings P1 and P2 have about 200 turns, while the secondary windings S1 and S2 have Θ20,000 and 2,000 turns, respectively. The secondary winding S2 consists of wire with a much greater thickness so that it has a lower resistance. The voltages with an open circuit on the secondary windings S1 and S2 are in the order of 35,000 ^v olt or 3,500 volts.

In the case shown in Fig. 1, the slotted or perforated disks C1 and 02 are arranged so that the disk C1 its associated power transistor T1 a few camshaft angles before switching the second power transistor 12 by the disk 02 turns off. The power transistor T1 causes a high secondary voltage of 35,000 volts in the secondary winding S1 when it is switched off, to initiate the initial ionization of the compressed fuel mixture between the ignition gap. Some crankshaft degrees the second power transistor T2 also switches

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out to the emergence of a voltage of 3,500 volts at the To effect secondary winding S2. Because this secondary winding S2 has a wire with a larger diameter than the secondary winding S1, it can carry a higher amperage, and this current supplements that flowing in winding S1 Electricity to maintain the required energy to the spark plug and therefore complete combustion of the lean Ensure fuel mixture in the cylinder.

In Pig. 2, the second embodiment uses only a single bistable optoelectronic trigger X and a single one Power module Q, consisting of a power Darlington pair. The collectors of the power Darlington pair are to the positive terminal of the battery via the relevant primary windings P1 and P2 connected. The turns ratios between the secondary windings and primary windings for the both ignition coils are 100 and 40, i.e.

N (S1) / N (P1) = 100
N (S2) / N (P2) = 40

To ensure that the coil with the higher turns ratio ionizes the gap first, a 50pP capacitor is used C between the connection between the ^ iode D2 and the secondary winding S2 and ground connected to the secondary voltage rise time of the coil with the smaller turns ratio. As in the first embodiment the first ignition coil supplies the high voltage to ionize the gap and the second ignition coil supplies the current to maintain the ignition.

The one in Pig. 3 shown modified version of the in Fig. The system shown provides two ignition coils with the same winding ratios. Because consequently both coils are able are to deliver essentially the same secondary voltage and the rise times of the voltages in their respective

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Jolamdlrwicklun, en ii: i \ v *; rontlichon are equal, Wein dan Lei: jtuii '3-l) arlin _t ; ton pair in module ■■ is switched off, is dc:, · capacitor G not me] ir required, and or is therefore taken out of the ochaltun ;:. It goes without saying that as a pole,; e, differentiated from Ferti, mn, ^, it is not possible to obtain coils v: it with identical characteristics, so that one coil always ionizes the gap before the other does. To you; Circuit, and its function is otherwise identical to the dei ^ jeni ^ s, which in connection with Fi ^. 2 has been described.

Usually in the examples according to Fig _{. 1} ^. 2 and J is only a single ignition gap / time, the system can of course be applied to a cylinder engine by providing a distributor as in the embodiment according to FIG. 1,; ezeir; t is.

Most of the above-mentioned plants ran in that a higher ignition energy is available in the combustion chamber represents, un with it a complete combustion of lean Allow fuel mixes while ensuring Wirt3 that the ignition is such that no ignition during the duration of the burn is present.

The j ^ rfindun / '; does not use petrol or diesel ignition limited, and it is in the same way for fuel gas or so.'ir oil burners applicable in industrial areas.

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Claims (8)

273403 « i'at en ban »prüche Zündun-jsanlaio,.; ο 1: c η η ζ e i c h η e t d u r υ Ii Coils whose GelcmidHrv / icklun-Jen go ^ eochaltet are dai3 same spark plug or the same ycrteilersysben i) ner _t; he is fed. 2. Zündungsanla ^ e according to claim 1, characterized in that υ inc Celnindärwickliuitf the The gap of the spark plug or spark plugs is always ionized before the other one does. 3. ZUndungsanlace according to jlnopruch 2, thereby; e indicates that the Cekunclärv / ickliuv- an ignition coil voltage; before the secondary cycle; ¹ ; the other Ziindspie 25U start delivering. 4 · Zündunijaanla ^ e according to claim 2, characterized in that the two secondary windings at the same time ;: voltage to supply bc inside. 5. Zündungsanla. ~ C according to one of claims 1 to 4, since through .- · α ] :. ο η η ζ eich η eb, thnß the 200 700Rftr, / Π761 BATH ORIGINAL v / ickluri -en joi / ciLs their energy through oino jeveili f.- diode unload. 6. 'iiindun:; anla e according to claim' 3, d a through e - 1: c η η ν, .. · rejects that the 3 second ^; irwicklun, en durcli jev / oili. ; e bistable optoelectronic l'ri ;;:; or ein und uus-,; e: jclial be ti / uL'dca, from which one etv / as triggers before the other. 7. Ziindui! ,.: Ulla, e after Anspziich 4, d a d u r c h.; ο - ke η η · ζ eieh η et that the Jelaindaiwicklun ^ en of a single; i eil bistable optoelectronisclien fri.; ,, it switched on and off! sclmellero Gtei-jzeit has, 8. Zündun ;; s.anln, '; e according to claims 7, dadurc ti; ek e η η ν, r pays that the verse ;; erun, should 1 be a capacitor, y. Ciuidiui.; Sanla /, e according to claim 4, characterized in that ·; e ken η ι; υ L c knot, that the two ignition coils have the same Hindun relationship and that their 'lekundärwicklun,; s of,. In em single optoeLektronir; f: hjn Tri ;,, it is switched on and off. 7 η π R & f. / Η 7