The ignition system in the car is designed to supply spark at the spark plug at a given time with the engine. In diesel engines, the fuel supply is called the ignition in the compression stroke. There are models of cars, in which the ignition system controls the fuel pump submerged.
There are 3 kinds of ignition systems:
1. Contact – control pulses occur when the contacts break.
2. Non-contact – switch pulses are generated (pulse generator), which is based on transistor circuits.
3. The microprocessor – the time of submission of the control pulses microprocessor controlled device that can simultaneously manage all the electric systems of the car.
All types of ignition systems have a similar principle. The scheme of the ignition system is shown in the figure below.
- 1 – ignition
- 2 – ignition coil
- 3 – way valve
- 4 – Candles
- 5 – chopper
- 6 – weight
To power the ignition system while driving generator is used, and when the engine is started – the battery. The ignition switch or the ignition switch is designed to supply power to the ignition system. It also provides power to the onboard network and retractor starter relay.
An important part of the ignition system is an energy storage device that collects and converts energy sufficient for the occurrence of discharge between the electrodes of a spark plug.Energy drives are inductive and capacitive.
The easiest inductive storage – a coil, is essentially an auto, which is connected to the power supply through the gap. The gap is set a special device such as cams ignition. At the exit of the coil creates a high voltage sufficient to breakdown airspace candles. Capacitive storage – storage capacity, which accumulated charge, and at the right time discharges a high voltage to the spark plug.
How do the spark plug?
Spark Plug – a device with two electrodes at a distance of 0.15-0.25 mm. Structurally, the candle – a porcelain insulator, attached to a metal thread – the first conclusion. The second conclusion – electrode is outputted through the center of the candle.
An important part of the ignition system is a distribution system consisting of distributor (timer), the switch (optional), the control unit. The objective of this system – feeding discharge from the drive to the spark at the right time.
Timer – a device for the distribution of the spark voltage. Distribution may be static and mechanical. Mechanical distribution includes a shaft, which distributes the voltage on wires runner and driven by a motor. Static allocation is made by the control unit, and each candle has a separate ignition coil.
Switch – a pulse generator, which is connected in series with the primary winding of the coil and receiving a signal from the control unit breaks the contact, due to which the self-induction voltage generated.
Control unit – microprocessor device which provides the necessary impetus to the coil at certain times. On the effect of BU affect the signals from the camshaft position sensor, crankshaft, temperature, oxygen sensors.
Also in the ignition system uses high voltage solid wire with a maximum insulation. For maximum discharge capacity at the candle should be made at the exact moment in time, a little before the fuel supply. Otherwise, due to high detonation engine to lose power.