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The contact system of ignition
Compressed working mixture in the cylinder ignites electric discharge — a spark generated between the electrodes of the spark plug. For the formation of electrical discharge in the conditions of JUA- the working mixture requires a voltage of not less than 12 16 sq. Converting low voltage current into high voltage and distribution to the engine cylinders is devices battery ignition. System mA ignition battery consists of current sources bottom who voltage, ignition coil, interrupter distribution- divider, condenser, spark plugs, switch for- jihane and wires low and high voltage circuit — low and high voltage. Low voltage circuit powered by a battery battery or generator. In this circuit except power sources consistently included the ignition switch, the primary Naya winding of the ignition coil with an additional resistor and breaker. The high voltage circuit consists of the secondary abmat- CI ignition coil, distributor, wires high voltage spark plugs. Education high voltage in coil for- gigane based on the principle of mutual induction. Including- turning the ignition switch contacts closed and pre- rivately the current from a battery or generator supplied to the primary winding of the ignition coil, after- of which is formed around the magnetic field. When mikania breaker contacts, the current in the primary winding ignition coils and magnetic flux around icesa- Ute. Disappearing magnetic flux crosses the coils of the WTO- hexadecimal and primary windings of the ignition coil and each house of them there is a small EMF. Thanks to larg- th number of turns of the secondary winding, in series with- United among themselves, the total voltage at its ends reaches 20...24 kV. From the ignition coil through high voltage wire- tion, distributor and wires high voltage is supplied to the spark plugs, resulting in between elek- the transfer electrodes of the spark occurs spark discharge, ignition the working mixture. The self-induction EMF that arises in the primary winding ignition coil, reaches 200...300 V, which calls for- the return of the disappearance of the magnetic flux and the appearance of sa my spark between the breaker contacts. For preventing the illumination of this phenomenon in parallel with the breaker contacts the capacitor is installed. The ignition coil transforms the current low voltage to high voltage (12 V to From 20 to 24 kV). It consists of the following main parts : the core, the primary winding of 250...400 Vit- Cove of thick insulated copper wire with a diameter of 0.8 mm, cardboard tube, the secondary winding 19 of 25 thousand... turns of thin wire of diameter 0.1 mm, of iron cor- with a span of magnetic circuits, karbolovoj caps, plugs and additional resistor. The secondary winding is located under primary and separated from it by a layer of insulation. The ends of the TRANS- primary winding the terminals karbolovoj roof CI. One end of the secondary winding is connected to the primary winding, and the second is displayed on the Central terminal Carbo- litovoi cover. The core is made from separate, isolated apart strips of transformer steel to reduce the stitching the formation of eddy currents. The lower end of the gel core- ka is installed in the porcelain insulator. Inside the coil is gigane filled with transformer oil. The extension consists of a spiral resistor, ceramic nests and two tires. Resistance ranges from 0.7 to 20 Ohms. One end of the resistor is connected by bus to the terminal VC, and other GOI to CMA. At low engine speed engine La breaker contacts for a long time are- Xia is closed, the current in the primary circuit of the who- melts, the resistor heats up, resistance increases in the circuit, the ignition coil receives a current of small force, it is protected from overheating. When the rotational speed of a crankshaft of the engine increase increases, the time closed state of the contacts is reduced- decreases, the current in the primary circuit decreases, the heating and the incremental resistance of the resistor decreases, prevents the voltage in the secondary circuit. When the starter motor is the resistor and zamorachivatsja start the engine is facilitated. The interrupter-distributor. Education current high who stress and its distribution in the cylinders of the engine the tell for timely ignition of the working mixture Dol- zhno to match the order of the cylinders. To induct a high voltage to the WTO- hex winding of the ignition coil, it is necessary periodand- Cesky release the primary circuit battery ignition that 249 and performs the circuit breaker. For current distribution of highly voltage in the cylinders respectively order work you engine is the distributor. Both of these device volun- the report contains one — breaker-distributor. The breaker is mounted on the engine and found in action by a camshaft. The main the breaker parts are the housing, drive shaft. Under- rolling equipment disk (which contains insulated growling- Joc contact and the stationary contact hour), servic- rolling equipment drive, centrifugal and vacuum regulators OPE- conservation, octane-corrector and a Cam with projections on the number cylinders. The Cam is connected with a drive roller via a centrifugal Governor. The breaker contacts napravle- us refractory metal is tungsten. The lever Prairie the user is mounted on the drive hinge and a contact in- imeetsya to a stationary contact spring. Torque- Xia drive roller Cams clicks on textolite the protrusion of the lever of the breaker and one turnover, breaks, and the spring will close the contacts as many times as there projections on the Cam. Opening the primary circuit of the ignition coil causing for the disappearance of magnetic flux crossing not only the coils of the secondary winding, and a primary, due what induces a current of self-induction voltage 200...300 V. This current, slowing down the disappearance of the current in the primary Noah chain, reduces EMF in the secondary circuit. Current self-induction also resulted in intensive spark- of between the breaker contacts and their destruction. That to prevent the harmful effects of EMF, apply the capacitor. The capacitor includes the parallel- but the breaker contacts and at the time of the existence of EMF sa monducci charged, preventing sparking on contact tah. In addition, a charged capacitor, discharging in the opposite direction leads to a rapid disappearance of the the current in the primary circuit, and hence the magnetic flux is ka, whereby the voltage in the secondary circuit of the dis- is. The capacitor consists of a varnished boom- GI, on which is deposited a thin layer of zinc and tin. This Boo the magician is the capacitor tube and rolled up. To the ends of the coil soldered one patch cord- nick. The roll is wrapped with cable paper and oil impregnated. The capacitor is mounted on the body outside or in MOV- dimensional disk breaker. The capacitance of the capacitor of 0.2 UF...0,17. Capacitors from metallized paper have the ability to samosas- to ostanavlivatsya in the breakdown of the dielectric by filling holes oil. Great impact on the operation of battery ignition Oka shows the gap between the breaker contacts. Normal the operation of battery ignition will be when the gap between the con- the bars of the breaker within 0,35...0,45 mm. If the gap is large enough, then the closed state States of the contacts will decrease and the current in the primary about- motke coils of ignition do not have time to rise to demand- value and, as a consequence, the EMF of the secondary circuit will not be sufficient. In addition, when the frequency rotation of the crankshaft will be interruptions to the RA- the bot engine. With a small gap occurs between the sparking strong contacts, their destruction and, as consequence, faults in all the operating conditions of the engine. The gap between the contacts of the Prairie- the user regulate the movement of the plate with the bar- sliding contact and with the help of the eccentric by loosening the pre-locking screw (Fig. 123). After control toos locking screw needs to be turned. Measure the gap at fully open contacts of the probe plate. |
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