- Nov 01, 2016 -

1,Can produce enough spark plug gap Breakdown voltage

Spark needed to breakdown and spark voltage called the breakdown voltage. Ignition system must be higher than the breakdown voltage of the secondary voltagecan jump the spark plug fires. Breakdown voltage is affected by many factors, which include:

(1) spark plug electrode clearance and shapes

Spark plug electrode gap larger, higher breakdown voltage;

Electrode tip of the angular, low Breakdown voltage required.

(2) gas mixture in the cylinder pressure and temperature

Mixture of more stress, lower temperature, higher breakdown voltage,

(3) the temperature of the electrode

Higher the temperature of the spark plug electrodes, electrode surrounding gas density is smaller, lower the breakdown voltage.

2,Spark with enough energy

When the engine is functioning, due to spontaneous combustion of gas mixture compression end temperatures close to their temperature, only 1~5mJ spark energy.But when the air/fuel mixture too thick or too thin, engine starting, idling, or when throttle opened sharply, you need high spark energy. And with modern engine of economy and improvement of exhaust gas purification requirements, all require increased spark energy. Therefore, in order to guarantee a reliable ignition, high energy electronic ignition systems generally should have 80~100mJ spark energy, starting the spark energy to be higher than 100mJ.

3,Ignition time should be adapted to the engine's working condition

First, the ignition system ignition in engine work order. Secondly, the ignition must be at the best of times.

Because the combustion in the air/fuel mixture in the cylinders take up a certain amount of time, so the mixture should not be ignition at TDC on the compression stroke, but should be well in advance, so that when the piston reaches TDC, the mixture had been burned, so that the engine for a larger power. Ignition ignition advance angle is commonly used to represent, that is, starting from issue spark until the piston reaches TDC of turn of the crank angle for some time.

If the ignition is too late, only ignition when the piston reaches the TDC, the blended combustion of gas, mainly in the piston downward in the course of, the combustion process in the case of volume increases, the hot gas to the cylinder wall increases the contact area, and into a relative reduction in the effective work of the heat,maximum combustion pressure in the cylinder and cause the engine to overheat, power is reduced.

If ignited prematurely, due to complete combustion of the mixture during compression, sharp increase in pressure within the cylinder, when the piston reaches TDC isreached before the largest piston recoil, negative work of the engine, not only reduced engine power, and may lead to a conflagration and run rough, accelerated damage to moving parts and bearings.

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