Breaker is an important appliance, car battery ignition system because of the breaker contact work repeatedly opening and closing, bearing ignition system of the primary circuit connected or cut off, and the ignition coil secondary circuit with high voltage is induced.
Due to the ignition secondary circuit is a typical resistor, inductor series circuit, and creates a continuously on the breaker contacts by electric spark ablation of bad environment, making it a battery ignition system and multiple parts of the engine failure.
, a battery ignition characteristics of battery ignition system consists of ignition coils, spark plug, breaker, distributor, ignition switch, high-voltage wire, etc, belong to the inductive energy storage type ignition system.
Battery ignition characteristics of ignition system can be summarized as follows: (
Ignition coil storage is directly proportional to the square of the ignition energy and the primary current.
In the case of primary current is constant, the greater the inductance, the more ignition energy storage.
As a result of the existence of inductance, determines the primary current changes according to the index law.
That is to say, after the contact closure, due to the potential function, the primary current will not immediately increases to a certain value, but increased gradually from zero.
When closing time infinite, primary current to reach a certain extreme.
Closing time depends on the engine speed and the closed contact Angle.
Under the condition of invariable in the Angle of contact closure, closure time inverse ratio to the engine speed.
It is not hard to see, the higher the engine speed, the primary current is smaller, the smaller the ignition energy.
This is a prominent characteristic of battery ignition system, also cannot overcome shortcomings.
It is because of the existence of the inductance, the ignition coil at the instant of the off contact, not only the secondary back emf is induced, at the same time also induced the primary voltage, make contacts between spark, ablation of contact.
The occurrence of the potential, not only make a spark between the contacts, and can reduce the rate of primary current is cut off, make secondary potential increase rate decrease.
Battery ignition system is sensitive to the spark plug carbon deposition, root right here.
According to the outstanding characteristics of battery ignition system, people take corresponding countermeasures, including ways to from the structure of the breaker.
Second, the structure characteristics of the breaker breaker is mainly composed of CAM, the contact pair, ignition advance device, etc.
Breaker CAM repeatedly in the process of rotary controls the closure of the contacts, on and off the primary current.
Is parallel capacitor and contact, its task is to give primary induction electric potential to form circuit, reduce contact ablation, speed up the rate of the primary current on and off.
Centrifugal ignition advance device and vacuum ignition advance device of the final effect is also reflected on the contact pair, the ignition advance Angle changes as the engine speed and load, in order to obtain the best ignition advance Angle.
Working condition of ignition system is not only affected by contact, and ignition advance device, capacitors and CAM technology conditions are closely related.
So when people analysis of working condition of ignition system should be linked to the related appliances and parts.
For example, when the edges and corners of CAM serious wear and tear, can affect the opening of the contact time.
Capacitor leakage, the contact will quickly ablation.
3, contact technology using analysis in terms of contact pair, the technical conditions include: the size of the gap, the size of contact area, contact surface ablation rate, spring tension.
The direct factors influencing the spring tension is the heating effect of the primary current.
When the generator voltage is on the high side, the primary current is larger, and the engine at low speed when work time is too long, when additional resistance short or ignition coil secondary coil short-circuit, spring will be due to the enhancement of thermal effect leads to annealing, tension.
Contact between the spark despite the capacitor protection, but still can not completely eliminate, so spark ablation function to contact nature is inevitable.
Contact ablation involves more factors;
(1) generator to adjust the voltage on the high side, the primary current is too large;
(2) the ignition coil and the capacity of capacitor mismatch;
(3) contact surface dirt or smaller contact area;
(4) capacitor defective or poor contact;
5. Contact gap is too big or too small;
6. The primary coil or additional resistance short-circuit;
All landowners engine at low speed running time is too long.
Affect both the size of the closed contact clearance Angle, the primary current and secondary voltage, also influence the ignition timing.
So the ignition timing adjustment, you must adjust the contact gap.
Contact gap of standard, general is 0.
35 mm -
In use, the ablation or wear the contact clearance, lead to the ignition voltage and ignition timing to change.
Contact the contact surface of influence on contact resistance, the primary current and secondary voltage, so to ensure that the contact two parallel interface is an important content of contact maintenance.
Anyhow, for ignition system of storage battery, breaker is both the key components, which is the most weak link.
Therefore, the daily maintenance of contact is vital.