Translation of "Retarded ignition" in German

The advance ignition f is plotted towards the top and the retarded ignition s is plotted towards the bottom.

A typical range for these special values S is approximately 0° through -4° retarded ignition.

Examples of this include operating states where manifold injection is accompanied by retarded ignition timing for catalytic converter heating during warm-up.

A method according to claim 1, wherein the ignition point is displaced in the direction toward retarded ignition during the non-steady operation.

For advanced ignition, the ignition spark necessary for ignition of the fuel/air mixture is emitted by the spark plug arranged on the left side of spark plug 170, and for retarded ignition, correspondingly, by the spark plug arranged on the right side of spark plug 170.

Assuming that spark plug 170 emits an ignition spark at the same time as in the case of the 0-degree position, the forward displacement of the top dead center point with respect to spark plug 170 results in retarded ignition.

A change in the ignition point is brought about by rotating the cam piece from its neutral position either clockwise or counterclockwise, thus displacing the top dead center point (TDC) clockwise or counterclockwise relative to the stationary spark plug or plugs, so that ignition of the fuel/air mixture takes place before or after the top dead center point is reached, corresponding to retarded or advanced ignition.

With this embodiment, advanced or retarded ignition is achieved by various activation of the respective spark plugs in order to generate an ignition spark.

Ignition angle ZW is additionally adjusted as a function of reference torque mdsoll in the direction of retarded ignition.

The time periods tS was selected in such a way that the constant retarded ignition angle was maintained for two to three ignitions.

Upon adjustment of the ignition timing ZZP to retarded ignition timing it is therefore to be expected that the engine speed n will drop, for example, when the ignition timing ZZP is changed from that of the power output curve 23 to the ignition timing ZZP correlated with the power output curve 21 .

Instead of a reduction of the fuel quantity x and an adjustment of the ignition timing to retarded ignition timing, it can also be provided that the fuel quantity is increased according to curve 32 ? shown in FIG.

If the predetermined ignition time point lies in the range of a retarded ignition after the top dead center TDC of the piston, the rpm lock circuit is always switched off when the ignition time point which is set lies later than the predetermined ignition time point.

Thus, deactivation of the rpm lock circuit 33 can already take place when the jump from retarded ignition to advanced ignition takes place, as is shown in FIG.

By means of a corresponding engine control unit with retarded ignition, or multiple fuel injection, during the cold start a hot CO— and hydrogen-rich exhaust gas is produced so that the combustion of hydrogen and CO on the oxidation catalytic converter 2 a, 2 b is rapidly initiated and as a result the exhaust gas quickly heats up the downstream exhaust gas purification components 2 and the outlet channels 4 of the heat exchanger.

If the load state changes from full load to idling, which is indicated at the dashed line 82, this results in section 83 in a change in the mixture quantity which is fed in, with the result that, in order to maintain the rotational speed, the ignition time point is adjusted, in particular, suddenly from retarded ignition in section 81 to advanced ignition, in section 83 .

Since the ignition timing ZZP 1 up to the limit engine speed n G is adjusted constantly to a comparatively late (retarded) ignition timing ZZP 1, even at very high partial load a uniform operation of the internal combustion engine 15 with minimal engine speed fluctuations is possible.

In this way, a wide engine speed range 33 for full load with advanced ignition timing ZZP and a wide engine speed range 32 for partial load with retarded ignition timing ZZP is enabled.

It has been found that in particular in case of a cold internal combustion engine, i.e., when the operating temperature of the internal combustion engine 15 is below a predetermined operating temperature, the retarded first ignition timing ZZP 1 leads to bad acceleration in the first engine speed range 32 .

In this context it is provided that upon engine speed change into the engine speed range 32, i.e., when the engine speed increases from the engine speed range 31 past the coupling engine speed n K or drops from the engine speed range 33 below the limit engine speed n G, the ignition timing ZZP first is adjusted to the second ignition timing ZZP 2 and the ignition timing ZZP is then adjusted stepwise to “retarded” to the ignition timing ZZP 1 as soon as the first criterion has been fulfilled.

If the fuel/air mixture in the combustion chamber has a strong tendency to knock, the adjustment angle will assume large values; in the context of this Application, the adjustment angle may be defined as a positive value, so that the ignition angle may be greatly retarded, i.e. ignition occurs at a time closer to top dead center.

The power increase causes a jerk on the tool member and this causes in turn the engine speed in a subsequent engine cycle to drop again below the limit engine speed resulting in a retarded ignition timing.

The method presented here is characterized in that the poor engine efficiency results primarily from the retarded ignition.

The division according to the invention reduces the wall heat losses, that is, the efficiency can therefore improve during the retarded ignition (which causes deterioration) compared to late ignited homogeneous mixture.

With an adequately large air charge as a consequence of the retarded ignition, critically small injection times can be avoided also with the conventional design of the injection valves which small injection times can occur for smaller air charges and pregiven maximum lambda (running limit condition).