The operating principle of contact ignition. Contact battery ignition system. Individual elements of the system

06.07.2020

This is the oldest existing system - in fact, it is the same age as the car itself. Abroad, such systems stopped being installed in series mainly by the end of the 1980s; in Japan even earlier, in our country such systems were installed on “classics” in the 21st century.

A mechanical breaker that directly controls the energy storage device (the primary circuit of the ignition coil). This component is needed to close and open the power supply. primary winding ignition coils. The breaker contacts are located under the ignition distributor cover. The leaf spring of the moving contact constantly presses it against the fixed contact. They open only for a short period of time, when the advancing cam of the drive roller of the breaker-distributor presses on the hammer of the movable contact. A capacitor is connected parallel to the contacts. It is necessary to ensure that the contacts do not burn at the moment of opening. When the moving contact is separated from the stationary one, a powerful spark can jump between them, but the capacitor absorbs most of the electrical discharge and the sparking is reduced to insignificance. But this is only half the useful work of the capacitor - when the breaker contacts are completely open, the capacitor discharges, creating reverse current in a low voltage circuit, and thereby accelerates the disappearance of the magnetic field. And the faster this field disappears, the greater the current appears in the circuit high voltage. If the capacitor fails, the engine will not work normally - the voltage in the secondary circuit will not be large enough for a stable

sparking.

The breaker is located in the same housing with the high-voltage distributor - therefore, the ignition distributor in such a system is called a breaker-distributor.

Brief operating principle looks like this - powered by on-board network is supplied to the primary winding of the ignition coil through a mechanical breaker. The breaker is connected to the crankshaft, which ensures that its contacts close and open at the right time. When the contacts are closed, charging of the primary winding of the coil begins; when it is opened, the primary winding is discharged, but a high voltage current is induced in the secondary winding, which, through a distributor, also connected to the crankshaft, is supplied to the desired spark plug.

This system also contains mechanisms for adjusting ignition timing - centrifugal and vacuum regulators.

The centrifugal ignition timing regulator is designed to change the moment of spark occurrence between the electrodes of the spark plugs, depending on the speed of rotation of the engine crankshaft.

The centrifugal ignition timing regulator is located in the distributor-distributor housing. It consists of two flat metal weights, each of which is fixed at one of its ends to a support plate rigidly connected to the drive roller. The spikes of the weights fit into the slots of the movable plate on which the bushing of the breaker cams is fixed. The plate with the bushing has the ability to rotate at a small angle relative to the drive roller of the breaker-distributor. As the engine crankshaft speed increases, the rotation speed of the distributor shaft also increases. The weights, obeying the centrifugal force, diverge to the sides and move the bushing of the breaker cams “in separation” from the drive roller. That is, the oncoming cam rotates at a certain angle along the rotation towards the contact hammer. Accordingly, the contacts open earlier, and the ignition timing increases.

When the rotation speed of the drive roller decreases, the centrifugal force decreases and, under the influence of the springs, the weights return to their place - the ignition timing decreases.

The vacuum regulator serves to increase the ignition timing when the engine load decreases (and vice versa). For this purpose, the vacuum created in the carburetor diffuser is used. The location of the inlet of the pipeline connecting the carburetor to the regulator is chosen so that at full load, idling and starting the engine, the vacuum does not reach the regulator or is insignificant. Due to these considerations, the inlet

located in front of the throttle valve. When the throttle valve opens, its edge passes past the inlet of the pipeline and the vacuum in it increases.

The vacuum through the elastic pipeline 1 enters the vacuum chamber of the regulator, located on the left side of the diaphragm 3.

When the engine is idling, the vacuum is low and the regulator does not work (Fig. 2.3, a). As the load increases (i.e., as the throttle valve opens), the vacuum in the vacuum chamber of the regulator increases. Due to the pressure difference (rarefaction in the vacuum chamber and atmospheric pressure), the elastic diaphragm 3 bends to the left, overcoming the resistance of spring 2 and dragging rod 5 along with it. This rod is pivotally connected to disk 6, on which contacts or sensors are located.

Moving the rod to the left (with increasing vacuum) leads to rotation of the support plate 7 in the direction opposite to the direction of rotation of the screen (Fig. 2.3, b). There is an earlier supply of a control pulse from the sensor or opening of the contacts and, therefore, earlier ignition. The maximum rotation of the disk, and, consequently, the maximum ignition timing is limited mechanically. When the throttle valve moves to the fully open position, the vacuum decreases, spring 2 causes the diaphragm, rod and disk to move in the opposite direction, resulting in a decrease in the ignition timing (later ignition). When the throttle valve is fully open, the regulator does not work (Fig. 2.3, c).

The ignition system of a gasoline engine is designed to ignite the air-fuel mixture. The combustion of this mixture occurs due to a spark.

Depending on how the process is controlled, the ignition system is divided into 3 types:

contact,
electronic.

In the contact system, the accumulation and distribution of sparks among the cylinders is controlled by a mechanical type device - a breaker-distributor ().

In a contactless ignition system, this function is performed by a transistor switch.

At electronic system ignition, the distribution of electrical energy is controlled by an electronic control unit (ECU).

Egnition lock. The ignition switch is usually located on the steering column or control panel. It controls the flow of current between the battery and the ignition system.
Battery. When the engine is not running, the source of electricity is. It also supplements the electricity produced by the generator if it produces less than 12 volts.
Distributor. The distributor directs the flow of high voltage current from the coil through the distributor handle to each of the spark plugs in turn.
Capacitor. A device called a capacitor is attached to the ignition distributor housing. It ensures that there is no spark between the open contacts of the breaker, which would lead to burning of the contact surfaces.
. A high voltage current passes through the central electrode of the spark plug. Then, a spark is formed in the gap between the central and side electrodes, igniting the fuel mixture in the cylinder.
Drive unit. Typically the distributor is driven directly from the camshaft. Its rotation speed is 1/2 the crankshaft rotation speed.
Coil. The coil consists of a metal housing containing 2 insulated winding wires wound around a mild steel core. The compression of the magnetic fields around the primary winding creates a high voltage current in the secondary winding, which goes through the distributor to the spark plugs.

Operating principle of the contact ignition system

The operating principle of the contact system is in the implementation of collection and conversion of low voltage ignition coil(12V) car electrical network y high voltage(up to 30 thousand volts), after which transmit and distribute voltage to the spark plugs, in order to create sparking on the spark plug at the right moment. Redistribution of high voltage across the cylinders is carried out through contacts.

A mechanical interrupter directly controls the energy storage process (primary circuit) and closes/opens the power supply to the primary winding.

Thus, the essence of the contact system’s operation lies in the following stages:

When the driver turns the ignition key, low voltage current from the battery is supplied to the primary winding of the ignition coil.
The current that appears on the primary winding forms a magnetic field.
Due to the fact that the engine is cranked (initially from the starter), the contacts of the cam breaker periodically open.
At the moment the circuit of the primary winding opens, the magnetic field also disappears, but due to the power lines crossing the turns of the primary and secondary windings, a high voltage current is induced in the secondary winding, and self-induction occurs in the primary winding (voltage no more than 300 volts).
The resulting high voltage current pulse is supplied to the distributor cap.
Where, due to the contacts, the current is distributed to each spark plug.
A spark discharge between the electrodes of the spark plug ignites the fuel-air mixture in the engine cylinder.

This type of ignition is used on classic domestic cars and some old foreign cars.

The self-induction current appears not only on the secondary, but also on the primary winding, which leads to burnt contacts and sparking.

1. No spark at the spark plugs

Possible reasons:

poor contact or open circuit in the low voltage circuit;
insufficient gap between the breaker contacts (burn);
failure of the ignition coil, capacitor, distributor cap (cracks or burning), breakdown of explosive wires or the spark plugs themselves.

Troubleshooting methods:

checking high and low voltage circuits;
adjusting the breaker contact gap;
replacement of faulty elements of the ignition system.

2. Engine runs rough

Possible reasons:

spark plug failure;
violation of the gap between the spark plug electrodes or in the breaker contacts;
the distributor cap or its rotor is damaged;
Incorrectly set or the ignition timing is off.

Troubleshooting methods:

checking and adjustment;
replacement of faulty elements;
setting the required gaps on the spark plugs and breaker contacts.

Even in its first modifications, a car engine was a complex structure consisting of a number of systems working together. One of the main components of any gasoline engine is the ignition system. Today we will talk about its structure, varieties and features.

Ignition system

The car's ignition system is a complex of instruments and devices that work to ensure the timely appearance of an electrical discharge that ignites the mixture in the cylinder. It is an integral part of electronic equipment and for the most part depends on the operation of the mechanical components of the motor. This process is inherent in all engines that do not use highly heated air for ignition (diesel, compression carburetor engines). Spark ignition of the mixture is also used in hybrid engines running on gasoline and gas.

The principle of operation of the ignition system depends on its type, but if we summarize its operation, we can distinguish the following stages:

process of high-voltage pulse accumulation;
charge passage through a step-up transformer;
synchronization and pulse distribution;
the occurrence of a spark at the spark plug contacts;
arson of the fuel mixture.

An important parameter is the advance angle or moment - this is the time at which the air-fuel mixture is ignited. The torque is selected so that the maximum pressure occurs when the piston hits the top point. In the case of mechanical systems, it will have to be set manually, but in electronically controlled systems, the setting occurs automatically. The optimal advance angle is influenced by driving speed, gasoline quality, mixture composition and other parameters.

Classification of ignition systems

Based on the ignition synchronization method, a distinction is made between contact and non-contact circuits. Based on the technology for forming the ignition timing, systems with mechanical adjustment and fully automatic or electronic systems can be distinguished.

Based on the type of charge accumulation, to break through the spark gap, devices with accumulation in inductance and with accumulation in capacitance are considered. According to the method of switching the primary circuit, the coils are of mechanical, thyristor and transistor varieties.

Ignition system components

All existing species Ignition systems differ in the way they create a control pulse, but otherwise their design is practically the same. Therefore, it is possible to indicate common elements that are an integral part of any variation of the system.

The primary power supply is the battery (used during startup), and during operation the voltage produced by the generator is used.

A switch is a device that is necessary to supply power to the entire system or turn it off. The switch is the ignition switch or control unit.

A charge accumulator is an element necessary to concentrate energy in the required volume to ignite the mixture. There are two types of components for accumulation:

Inductive - a coil, inside of which there is a step-up transformer that creates a sufficient impulse for high-quality arson. The primary winding of the device is powered from the positive side of the battery and goes through a breaker to its negative side. When the primary circuit is opened by a breaker, a high-voltage charge is created on the secondary circuit, which is transferred to the spark plug.
Capacitive - a capacitor that is charged with increased voltage. At the right time, the accumulated charge is transmitted to the coil via a signal.

Operation scheme depending on the type of energy storage

Candles are a product consisting of an insulator (the base of the candle), a contact terminal for connecting a high-voltage wire, a metal frame for fastening the part and two electrodes, between which a spark is formed.

The distribution system is a subsystem designed to direct the spark to the desired cylinder. Consists of several components:

A distributor or distributor is a device that compares the crankshaft speed and, accordingly, the working position of the cylinders with the cam mechanism. The component may be mechanical or electronic. The first one transmits the rotation of the motor and, using a special slider, distributes the voltage from the drive. The second (static) excludes the presence of rotating parts; distribution occurs due to the operation of the control unit.
A commutator is a device that generates coil charge pulses. The part is connected to the primary winding and breaks the power supply, generating a self-induction voltage.
The control unit is a microprocessor-based device that determines the moment of current transmission to the coil based on sensor readings.

The wire is a single-core high-voltage conductor in insulation that connects the coil to the distributor, as well as the switch contacts to the spark plugs.

Magneto

One of the first ignition systems is a magneto. It consists of a current generator that creates a discharge solely for sparking. The system consists of a permanent magnet, which is driven by the crankshaft and an inductor. A spark capable of breaking through the spark gap is generated by a step-up transformer, one part of which is the rough winding of the inductor. To increase the voltage, a part of the generator winding is used, which is connected to the spark plug electrode.

Magneto ignition system

Control over the supply of a spark can be contact, made in the form of a breaker, or non-contact. With the non-contact spark supply method, capacitors are used to improve the quality of the spark. Unlike the ignition circuits presented below, a magneto does not require a battery, it is lightweight and is actively used in compact equipment - brush cutters, chainsaws, generators, etc.

Contact ignition system

An outdated, common scheme for igniting the fuel mixture. Distinctive feature The system is to create high voltage, up to 30 thousand V per spark plug. This high voltage is created by a coil that is connected to the distribution mechanism. The pulse is transmitted to the coil thanks to special wires connected to the contact group. When the cams open, a discharge and spark are formed. The device also acts as a synchronizer, since the moment of spark formation must coincide with the desired moment of the compression stroke. This parameter set by mechanical adjustment and shifting the spark to an earlier or later point.

The simplest scheme

The vulnerable part of this option is natural mechanical wear. Because of it, the moment of spark formation changes, it is unstable for different positions of the slider. As a result, engine vibrations appear, its dynamics decrease, and the uniformity of operation deteriorates. Fine adjustments can get rid of obvious faults, but the problem may reoccur.

The advantage of contact ignition is its reliability. Even with serious wear, the part will work flawlessly, allowing the motor to work. The circuit is not picky about temperature conditions and is practically not afraid of moisture or water. This type of ignition is common on older cars and is still used on a number of production models today.

Contactless ignition

The principle diagram of the contactless system is somewhat different. It retains the distributor as a structural element, but it only performs the function of synchronizing the cylinders and sends an impulse to the switch. In turn, the transistor element is synchronized with the sensor indicator and determines the ignition angle, as well as other settings, automatically.

The advantage of the system is the stability of the quality of sparking, which does not depend on manual settings or preservation of the contact surface. If we consider the superiority of this option over the contact circuit, we can highlight:

the system generates a spark High Quality constantly;
the design of the ignition system prevents deterioration of its operation due to wear or contamination;
there is no need to produce fine settings ignition angle;
there is no need to monitor the state of the contacts, control their closure angle and other settings.

As a result of using a contactless system, one can observe a decrease in fuel consumption, improved dynamic characteristics, the absence of strong engine vibrations, and a stable spark makes cold starts easier.

Electronic ignition

A modern, most advanced design that completely eliminates the presence of moving parts. To obtain the necessary data on the position of the crankshaft and others, special sensors are used. Next, the electronic control unit makes calculations and sends appropriate impulses to the working components. This approach allows you to determine the moment of spark supply as accurately as possible, so that the mixture is ignited in a timely manner. This allows you to get more power, improve cylinder purging and reduce harmful emissions due to better fuel combustion.

Electronic system diagram

The electronic ignition system of a car is highly stable and is installed on most modern cars. This popularity is determined by the advantages of this scheme:

Reduced fuel consumption in all engine operating modes.
Improved dynamic performance – response to the gas pedal, acceleration speed, etc.
Smoother motor operation.
The graph of torque and horsepower is aligned.
Power loss at low speeds is minimized.
Compatible with gas equipment.
A programmable electronic unit allows you to configure the engine to save fuel or, conversely, to increase dynamic performance.

The purpose of the ignition system is quite simple; it is an integral part of a gasoline engine, as well as engines equipped with gas equipment. This component is constantly changing and acquiring new forms that meet modern requirements. Despite this, even the simplest ignition models are still used on various equipment, successfully doing their job, just like decades ago.

Autoleek

Ignition coil. The ignition coil serves to convert low voltage current into high voltage current. It is an electrical autotransformer with an open magnetic circuit. The design of all coils is almost the same, the differences are only in the winding data, methods of connecting the secondary winding, design features of individual components and parts, as well as in the material for filling the internal cavities.

On vehicles with a contact ignition system, oil-filled coils B102-B or B13 are installed. The filling improves the insulation of the windings and ensures heat dissipation. Transformer oil is used as a filler.

Ignition coil B13 (Fig. 12.2) consists of a core 15 made up of individual plates of electrical steel, insulated with each other by scale to reduce eddy currents generated by pulsating magnetic field. An insulating tube is put on the core, on which a secondary winding 13 is wound. A primary winding coil 12 is placed on top of the secondary winding, the ends of which are placed in insulating tubes 6 and connected one to terminal 4, and the other to the “VK” terminal. The secondary winding 13 is connected at one end to the end of the primary winding 12, and at the other to the output terminal 1 through conductor 9 and spring 3, which is pressed against the brass insert 19. The primary winding usually has 250-400 turns, and the secondary - 19-26 thousand. turns. To enhance the magnetic flux penetrating the secondary winding, a ring magnetic core 10 is installed on top of the windings.

All parts of the coil are placed in a stamped steel housing 8 and isolated from it by an insulator 14.

An additional resistor-variator 16 (SE 102), which is a spiral of soft steel wire and placed in a ceramic insulator 17 mounted on a bracket 7, is connected in series with the primary winding of the coil. The ends of the additional resistor are connected by buses 18 to the terminals "VK" and "VK- B". The variator prevents a decrease in voltage in the secondary winding when the engine is running at high crankshaft speeds, and also facilitates starting the engine with a starter.

Shielded ignition coils have a metal casing mounted on the cover

Fig. 12.2. Ignition coil

At a low engine speed, the breaker contacts are closed for a sufficiently long time and the current in the primary circuit increases to its maximum value. At the same time, the variator spiral heats up, which increases the resistance of the circuit. This limits the current in the primary circuit, and, consequently, the heating of the coil.

As the crankshaft rotation speed increases, the time the contacts are closed decreases and the current strength in the primary circuit does not have time to increase to the maximum. At the same time, the heating of the variator spiral decreases, its resistance drops and the current passing through the primary winding does not decrease so significantly. Due to this, the voltage induced in the secondary winding remains high enough and ensures uninterrupted operation of the engine.

When starting the engine with the starter, the voltage at the terminals is greatly reduced. battery. At the same time, the starter solenoid relay short-circuits the additional resistor 18 (Fig. 12.1) and thereby compensates for the voltage drop at the ends of the primary winding. As a result, a voltage is induced in the secondary winding of the ignition coil, ensuring reliable engine starting.

The ignition coil is a non-separable unit and cannot be repaired during operation.

Breaker-distributor. This device interrupts the low-voltage current circuit at the required moment and distributes the high-voltage current among the spark plugs in accordance with the operating order of the cylinders, and also adjusts the ignition timing depending on the crankshaft speed and engine load. The breaker-distributor consists of a low-voltage current breaker, a high-voltage distributor, centrifugal and vacuum ignition timing regulators, an octane corrector and a housing. Depending on the number of engine cylinders, distributors are made with four, six or eight sparks, and depending on the direction of working rotation - left and right rotation

Rice. 12.3. Breaker-distributor

a-general device; b-top view without cover and rotor; e-mode operation of the vacuum regulator; g-octane corrector; d-centrifugal regulator

The design and principle of operation of the breaker-distributor is best viewed on a contact-type device (Fig. 12.3).

Two copper-graphite bushings 31 are pressed into the housing 25, serving as a bearing for the drive shaft 29 of the cam clutch 8 of the breaker, the distributor rotor 10 and the centrifugal regulator. The roller 29 receives rotation from the lubrication pump drive shaft.

The breaker is mounted on a movable disk 4, which is mounted on a ball bearing 2, pressed into the hole of a fixed disk 3 attached to the housing 25. Disks 4 and 3 are connected to each other by a flexible copper wire 5 to improve the reliability of the connection of the movable disk to ground.

The movable contact 18 on the textolite block 17 is installed on an axis fixed to the movable disk 4 and is isolated from ground. Under the action of the leaf spring 16, the movable contact of the breaker is pressed against the stationary 19, fixed to the bracket and connected to ground. The contacts are made of tungsten. The bracket together with the fixed contact can be turned by screw 37 (Fig. 12.3.6) of the eccentric, with the help of which the gap between the contacts is adjusted (0.35 - 0.45). The gap is checked with a flat feeler gauge and adjusted at maximum contact separation. After adjustment, the gap is fixed with locking screw 38.

Movable contact 18 (Fig. 12.3, a) through spring 16 and wire 5 is connected to insulated terminal 7 of the housing, to which the low voltage wire from the ignition coil is connected.

To lubricate the edges of the jaw coupling 8 and the upper end of the roller, there are felt wicks 9 and 6, and for lubricating the bushings there is a 31-cap oiler 28.

A capacitor 34 is connected parallel to the contacts. One of its plates is connected to ground, and the other to terminal 7 of the breaker-distributor.

Capacitor(Fig. 12.4) consists of a body 7, in which a roll 4 is placed, consisting of two plates 9 of tin and zinc, applied in a thin layer to sheets of paper 8. The layer of metals is not applied across the entire width of the paper. Solder is sprayed onto the ends of roll 4, to which flexible wires 2 and 5 are soldered. Roll 4 is wrapped in cable paper 6. Conductor 5 is passed through holes in housing 7 and soldered to it. Conductor 2 from another plate is soldered to a brass terminal in textolite washer 1. Washers 1 and 3 ensure the tightness of the housing. The free space in the housing is filled with transformer oil.

Rice. 12.4. Capacitor:

a-device; b-plating of the capacitor; c-symbol

The capacitance of the capacitor should be in the range of 0.17-0.25 microfarads. With a smaller capacitance, sparking at the breaker contacts increases, which leads to their burning; with a larger capacitance, the voltage in the secondary winding of the ignition coil decreases.

High voltage current distributor consists of a rotor Yu (Fig. 12.3, c) and a cover 11, reinforced with spring latches 15 on the body 25. A brass spacer plate is attached to the carbolite rotor 10. The rotor is mounted on the upper part of the cam clutch 8, which has a flat (cut) for the correct relative position of the rotor and the cam protrusions.

The correct position of the cover relative to the body is ensured by a pin on the body that fits into the groove of the cover.

The lid contains central 14 and lateral 12 electrodes made of brass. A spring is inserted into the hole of the central electrode from below, pressing the carbon contact 13 to the rotor spacer plate.

It takes several thousandths of a second to burn the working mixture. Therefore, the mixture is ignited before the piston reaches TDC. with some advance.

The angle by which the crankshaft crank does not reach TDC. when the working mixture is ignited in the combustion chamber, it is called the ignition timing angle, which for different engines ranges from 28° to 45°. Its value depends on the crankshaft speed, load, type of fuel used and other factors.

The ignition timing angle changes automatically depending on the engine operating mode. Initially it is installed manually.

Centrifugal regulator! ignition timing lator changes the ignition timing depending on the engine speed.

A plate 27 is pressed onto the corrugated part of the roller 29 (Fig. 12.3, a, d), on which weights 26 of the centrifugal ignition timing regulator are installed on the axles. Cam clutch 8 has a number of faces equal to the number of engine cylinders, and can be rotated relative to the axis of the roller 29 at a certain angle. The coupling is fastened to cross-beam 1 with screw 30.

As the rotation speed of the roller 29 increases, the weights 26 of the regulator diverge under the action of centrifugal forces, overcoming the resistance of the springs 32. The pins of the weights rotate the traverse 1 and the cam clutch 8 in the direction of rotation of the breaker-distributor shaft. The cam protrusions approach the moving contact earlier and open the breaker contacts, which increases the ignition timing. When the engine crankshaft speed decreases, the ignition timing decreases, because due to the decrease in centrifugal forces, the weights converge under the action of spring 32.

Vacuum ignition timing regulator changes the ignition angle depending on the engine load.

The vacuum regulator attached to the body 25 of the breaker consists of a chamber 20, a diaphragm 24 with a rod 21 and a spring 23. The operation of the vacuum regulator is shown in Fig. 12.3, c.

As the engine load decreases, the vacuum behind the closed throttle valve increases and is transmitted through a tube connected to fitting 22 to the vacuum regulator. Under the influence of vacuum, diaphragm 24, overcoming the resistance of spring 23, bends to the right. The rod 21 turns the movable disk 4 against the direction of rotation of the distributor roller 29. The cam protrusions approach the moving contact earlier and open the breaker contacts, which increases the ignition timing. As the engine load increases, the vacuum behind the opening throttle valve and in the vacuum regulator drops, spring 23 bends diaphragm 24 to the left, and rod 21 turns disk 4 in the direction of rotation of roller 29. The breaker contacts open later, which reduces the ignition timing.

When the engine is forced to switch to fuel with a higher or lower octane number, the ignition timing is adjusted using an octane corrector. To operate the engine on fuel with a lower octane number, the ignition timing is reduced, and to operate on fuel with a higher octane number, it is increased.

The octane corrector is located at the bottom of the body 25 (Fig. 12.3, a.d) of the breaker and consists of the lower 35, middle 33 and upper 39 plates. The middle plate 33 has an oval hole for a screw 36 securing it to the bottom plate 35, and a bracket 45 with an adjusting screw 43. The bottom plate 35 has a scale and a bracket 41 for holding the adjusting nuts 42 and 44 in bracket 45. The upper plate 39 is attached to the body 25 of the breaker, and with a screw 40 to the middle plate 33.

The ignition timing is changed by rotating the distributor-chopper housing using octane-corrector nuts 42 and 44 and checked using a scale and arrow.

The actual ignition timing angle is the sum of the initial setting angle and the angles set by the octane corrector, centrifugal and vacuum regulators.

Changing the gap in the breaker contacts leads to a decrease or increase in the ignition timing. Therefore, before setting the ignition timing on the engine, it is necessary to first check and, if necessary, adjust the gap between the contacts.

The breaker-distributor described above has one significant drawback, as does the entire contact ignition system, namely the inevitable burning of the breaker contacts. As a result, the starting properties of the engine deteriorate, the voltage of the secondary winding decreases, and, consequently, the spark energy.

The contactless ignition system, which will be discussed below, does not have these shortcomings.

Sweeping candle(Fig. 12.5, a) creates a spark discharge that ignites the working mixture compressed in the engine cylinders. It consists (Fig. 12.5,6) of a steel body 4 with a thread and a side electrode 6. An insulator 3 with a central electrode 5, a contact device and sealing parts are rolled into the body. Insulators have high mechanical strength and insulation resistance at high temperatures. The spark plug electrodes and the knurled central rod are made of nickel-manganese or chromium-nickel steel. The knurling ensures a strong connection with the conductive glass sealant. The gap between spark plug electrodes 5 and 6 is 0.6 - 0.8 mm. During engine operation, the gap increases by an average of 0.015 mm per 1 thousand km of vehicle mileage. A sealing metal washer 8 is installed between the housing and the insulator 3, which ensures the tightness of the connection. The sealed fastening of the spark plug in the block head is ensured by a metal-asbestos sealing ring 9 made of soft metal.

Rice. 12.5.Spark plug

a - general view; b - candle in section; c - shielded candle; 1 - contact nut; 2 - rod; 3 - insulator; 4 and 19 - buildings; 5 - central electrode; 6 and 21 - side electrodes; 7 - sealant; 8 - washer; 9 - sealing ring; 10 - wire shielding; 11 - bushing; 12 - union nut; 13 - rubber bushing; 14 - high voltage wire; 15 - contact device; 16 - ceramic bushing; 17- suppressive resistor; 18 - screen; 20 - ring

Spark plugs operate under very difficult conditions, being exposed to high voltage (up to 25 kV), high gas pressure (up to 4 MPa) and temperature changes from 40 to 2500 ° C.

To ensure uninterrupted operation of the spark plug, the lower part of the thermal cone of the insulator must have a temperature in the range of 500-600 ° C. At this temperature, carbon deposits deposited on the thermal cone of the insulator burns out, i.e. The candle self-cleanses. With less heat, the electrodes of the spark plug will become covered with soot. In this case, the candle will work intermittently.

If the temperature of the insulator and the central electrode is too high (more than 800°C), glow ignition occurs when the working mixture ignites from contact with the heated cone of the insulator and the central electrode until a spark appears between the electrodes of the spark plug. As a result, the working mixture ignites too early.

A characteristic of the thermal properties of a candle is the glow number, which is determined in a special installation for the occurrence of glow ignition.

Non-separable design spark plugs produced by the domestic industry are designed for specific types of cars and are marked accordingly. The symbol of the candle contains the designation of the thread on the body (A-metric thread 14x1.25 or M-metric thread 18x1.5), heat number 8, 11, 14, 17, 20, 23 or 26, designation of the length of the threaded part of the body (H- 11mm, D-19mm), designation of the protrusion of the thermal cone of the insulator beyond the end of the body B, designation of sealing at the connection of the insulator - the central electrode with thermal cement -T.

The length of the threaded part of the body (12 mm), the absence of protrusion of the thermal cone of the insulator beyond the end of the body and the sealing of the insulator-central electrode connection with a sealant other than thermal cement are not indicated.

The shielded spark plug kit (Fig. 12.5c) includes a rubber sealing sleeve 13 that seals the wire entry into the spark plug, a ceramic insulating sleeve 16 of the screen, a copper sealing ring 20 and a ceramic liner with a built-in suppression resistor 17. This resistor is designed to reduce the level of radio interference by the system ignition and reducing burnout of spark plug electrodes.

Contact of the wire with the electrode is carried out using contact devices of the KU-20A type. The connection is made as follows. The rubber sealing sleeve 13 of the spark plug is put on the end of the high voltage wire 14 coming out of the shielded hose 10, and then the wire is inserted into the contact device. The wire core, exposed to a length of 8 mm, is inserted into the hole of the sleeve, flared in the bottom of the ceramic cup of the contact device 15, and fluffs out so that the contact device is clamped on the wire. Spark plugs of this type (SN-307) are installed on ZIL-131 vehicles.

Ignition switch. This device is designed to turn on and off ignition devices and connect control and measuring instruments, windshield wiper and heater motors, radio receivers and starter switching relays (at the moment of starting) to the power source. The switch and lock itself are placed in the switch housing, cast from a zinc alloy. On the plastic cover of the switch there are terminals “AM” (ammeter), “KZ” (ignition coil), “ST” (starter) and “PR” (receiver). Using the key, the lock contact group can occupy four positions: 0 - all off; When the key is turned clockwise to a fixed position 1, the ignition and receiver are turned on, as well as instrumentation. To start the engine, you must turn the key clockwise to the “P” position - the starter switch relay and ignition devices are connected to the current source. When turning on the receiver while parked, you must turn the ignition key counterclockwise to the fixed position.

Sparking between the spark plug electrodes, the rotor and distributor cap electrodes, breaker contacts, as well as in other electrical equipment causes high-frequency electromagnetic oscillations that interfere with radio and television reception. The most severe interference is caused by the ignition system. To eliminate interference use:

Inclusion of suppressive resistances in high voltage wires;

Shielding of the electrical equipment system;

Blocking sparking contacts with high-capacity capacitors;

The use of special radio interference filter devices.

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Introduction

In the first engines (for example, the Daimler engine, as well as the so-called semi-diesel), the mixture of fuel and air was ignited at the end of the compression stroke from a red-hot glow head - a chamber communicating with the combustion chamber (synonym - glow tube). Before starting, the glow head had to be heated with a blowtorch, then its temperature was maintained by the combustion of fuel while the engine was running. Currently, glow engines used in industrial applications operate on this principle. various models(aircraft, auto, ship models). Glow ignition in this case benefits from its simplicity and unsurpassed compactness.

Diesel engines also do not have an ignition system; the fuel ignites at the end of the compression stroke from the highly heated air in the cylinders.

Compression carburetor engines do not require an ignition system; the air-fuel mixture is ignited by compression. These engines are also used in modeling.

But the spark ignition system has really taken root on gasoline engines, that is, a system whose distinctive feature is the ignition of the mixture by an electric discharge breaking through the air gap between the electrodes of the spark plug.

There are currently three ignition systems: magneto ignition, battery ignition using a car battery, and batteryless ignition using a motorcycle alternator.

We can distinguish: circuits without the use of radio-electronic components (“classical”) and electronic.

My thesis examines the classic contact ignition system.

The contact ignition system is the oldest type of ignition system. Currently this system used on some models of domestic cars (the so-called “classics”). The creation of high voltage and its distribution among the cylinders in this system occurs using contacts.

1. Contact ignition system design

1.1 Purpose of the contact ignition system

The ignition system is a set of all instruments and devices that provide the appearance of an electric spark that ignites the air-fuel mixture in the cylinders of an internal combustion engine at the right moment. This system is part common system electrical equipment. The ignition system serves to ignite the working mixture in the engine cylinders at strictly defined moments. Ignition of the mixture can be carried out by a battery ignition system or from a magneto. The vehicles studied use a battery ignition system. Based on the method of interrupting the primary circuit current, battery ignition systems are divided into contact, contact-transistor and contactless transistor. Until 1960, cars were mainly equipped with a contact ignition system. Currently, transistor ignition systems are increasingly used, especially on eight-cylinder engines.

1.2 Operating principle of the contact ignition system

Ignition system

The ignition system is used only in gasoline and gas engines. With its help, the air-fuel mixture entering the engine cylinders is ignited at a strictly defined point in time. Ignition of the mixture inside the cylinder occurs when a spark forms between the electrodes of the spark plug when a current of 18,000-20,000 V is supplied to it.

There are three types of ignition systems:

· contact,

· contactless and

· microprocessor.

The contact system is not used on modern cars. However, it was previously widespread. Let's give it its due, since it served faithfully for many years, and consider its fundamental structure. The operating principle is based on the law of electromagnetic induction. From the battery, when the ignition is on and the breaker contacts are closed, a low voltage current passes through the primary winding of the ignition coil, forming a magnetic field around it. Opening the contacts of the breaker leads to the disappearance of the current in the primary winding and the magnetic field around it. The disappearing magnetic field induces a high voltage (about 20-25 kilovolts) in the secondary winding. The distributor alternately supplies high voltage current to high-voltage wires and spark plugs, between the electrodes of which a spark charge jumps, and the air-fuel mixture in the engine cylinders ignites.

The disappearing magnetic field crosses not only the turns of the secondary, but also the primary winding, as a result of which a self-induction current of about 250-300 volts appears in it. This leads to sparking and burnt contacts, in addition, the interruption of current in the primary winding slows down, which leads to a decrease in voltage in the secondary winding. Therefore, a capacitor (usually with a capacity of 0.25 μF) is connected in parallel with the contacts of the breaker.

An additional resistance (or additional resistor). At low speeds, the breaker contacts are in the closed state most of the time and a current flows through the winding, more than sufficient to saturate the magnet wire. Excess current heats up the coil unnecessarily. When the engine starts, the additional resistance is shunted by the contacts of the starter relay, thereby increasing the energy of the electric spark at the spark plug. Operating principle of the contact ignition system

When the breaker contact is closed, low voltage current flows through the primary winding of the ignition coil. When the contacts open, a high voltage current is induced in the secondary winding of the ignition coil. Via high-voltage wires, high-voltage current is supplied to the distributor cap, from which it is distributed to the corresponding spark plugs with a certain ignition timing.

As the engine crankshaft speed increases, the distributor chopper shaft speed increases. The weights of the centrifugal ignition timing regulator diverge under the influence of centrifugal force, moving the movable plate with the breaker cams. The breaker contacts open earlier, thereby increasing the ignition timing. When the engine crankshaft speed decreases, the ignition timing decreases.

A further development of the contact ignition system is the contact-transistor ignition system. In the circuit of the primary winding of the ignition coil, a transistor switch is used, controlled by the breaker contacts. In this system, due to the use of a transistor switch, the current in the primary winding circuit is reduced, thereby increasing the service life of the breaker contacts.

Scheme 1.2.1

1. The ignition key is turned, which allows low voltage battery current to flow to the primary winding of the ignition coil.

2. When a current appears on the primary winding, a magnetic field appears.

3. The breaker contacts open due to cranking of the engine, which is initially driven by the starter.

4. The low voltage current and the magnetic field, which induces a high voltage current on the secondary winding, disappears.

5. The generated high voltage current flows to the central terminal of the ignition coil, and from there to the distributor cap.

6. The distributor distributes current to each spark plug.

7. The current that appears on the spark plug forms a spark discharge between the electrodes, which ignites the fuel-air mixture.

The self-induction current appears not only on the secondary, but also on the primary winding, which leads to burnt contacts and sparking. Another influence is interruption of the current in the primary winding, which reduces the voltage in the secondary. To reduce the effect, a capacitor connected in parallel to the breaker contacts is used

Scheme 1.2.2 of the classic contact ignition system:

1 -- battery; 2, 3 -- ignition switch contacts; 4 -- additional resistor; 5 -- ignition coil; 6 -- breaker; 7, 8 -- movable and fixed contacts of the breaker; 9 -- cam; 10 -- distributor; 11 -- rotor (runner); 12 -- fixed electrode; 13 -- spark plugs; 14 -- capacitor.

1.3 Contact ignition system devices

ignition system engine

The design features of contact ignition system devices are as follows.

The contact ignition system consists of the following elements: power supply, ignition switch, low voltage mechanical circuit breaker, ignition coil, high voltage mechanical distributor, centrifugal ignition timing regulator, vacuum ignition timing regulator, spark plugs and high voltage wires.

The mechanical breaker is designed to open the low voltage circuit (the primary winding circuit of the ignition coil). When the contacts open, a high voltage is induced in the secondary circuit of the ignition coil. To protect the contacts from burning, a capacitor is connected in parallel to the contacts.

The ignition coil serves to convert low voltage current into high voltage current. The coil has two windings - low and high voltage.

The mechanical distributor ensures the distribution of high voltage current across the engine cylinder spark plugs. The distributor consists of a rotor (commonly called a “runner”) and a cover. The cover has central and side contacts. The central contact is supplied with high voltage from the ignition coil. Via the side contacts, high voltage is transmitted to the corresponding spark plugs.

The chopper and distributor are structurally combined in one housing and are driven by the engine crankshaft. This device has the general name of a breaker-distributor (the common name is “distributor”).

The centrifugal ignition timing regulator is used to change the ignition timing depending on the engine crankshaft speed. Structurally, the centrifugal regulator consists of two weights. The weights act on the movable plate on which the breaker cams are located.

The ignition timing is the angle of rotation of the engine crankshaft at which high voltage current is supplied to the spark plugs. In order for the fuel-air mixture to burn completely and efficiently, ignition is carried out in advance, i.e. until the piston reaches top dead center.

The ignition timing is set by adjusting the position of the distributor-distributor in the engine.

The vacuum ignition timing regulator provides a change in the ignition timing depending on the engine load. The load on the engine is determined by the degree of throttle opening (gas pedal position). The vacuum regulator is connected to the cavity behind the throttle valve and, depending on the degree of vacuum in the cavity, changes the ignition timing.

The high voltage wires carry high voltage current from the ignition coil to the distributor and from the distributor to the spark plugs.

The spark plug is designed to ignite the fuel-air mixture by generating a spark discharge.

1.3.1 Contact ignition system devices

1.3.2 Diagram of ignition elements on a Moskvich (AZLK) 2140 car

Description of ignition system elements

1 Drive coupling.

2 Cam plate.

3 Oiler spring.

4 Oil can.

5 Capacitor.

6 Distributor housing.

7 Low voltage terminal.

8 Cam.

9 Distributor cap.

10 Runner.

11 Slider contact plate

12 Contact carbon spring.

13 Contact angle.

14 Cam oil seal.

15 Spring for securing the distributor cap.

16 Centrifugal regulator spring.

17 Centrifugal regulator weight.

18 Bearing.

19 Distributor roller with plate.

20 Filz cam.

21 Fixed breaker plate.

22 Vacuum regulator rod.

23 Vacuum regulator.

24 Movable breaker plate.

25 Fixed contact.

26 Screw securing the contact post.

27 Contact stand.

28 Breaker lever.

29 High voltage wire.

30 Rubber cap.

31 Linen core.

32 Insulation.

33 Conductive conductor.

34 Wire tip.

35 Vacuum regulator diaphragm.

36 Vacuum regulator spring.

37 Spark plug body.

38 Contact terminal.

39 Spring bracket.

40 Side electrode.

41 Central electrode.

42 Heat sink washer.

43 Gasket.

44 Spark plug body.

45 Insulator.

46 Glass sealant.

47 Contact rod.

1.4 Specifications ignition systems Moskvich 2140

Rated supply voltage - 12±0.2V

Allowable voltage changes - from -7.8 to +18.2 V

Voltage amplitude developed in the primary short-circuit circuit - ± 500 V

Average current consumption, no more than - 2.5 A

Current consumption at 600 ±60 rpm of the distributor shaft - 0.4 A

Current consumption at 4000 ±400 rpm of the distributor shaft - 4.5 A

Current consumption through breaker contacts, no more than - 0.3 A

2. T.O. and repair of contact ignition system

2.1 Organization of a car repair mechanic’s workplace

The main workplace of a car mechanic outside of the posts and lines of maintenance and repair is a post equipped with a mechanic's workbench, on which components and devices removed from the car are disassembled and assembled and fitting and other work is performed.

The workbench cover is covered with thin sheet (roofing) steel, which protects it from damage and makes it easier to keep clean.

When starting work, a car mechanic must prepare all the tools and devices necessary to complete it and correctly position them on the workbench.

An important role is played by maintaining tools and devices in good condition and following the rules for using them. For ease of work, the vice must be mounted on the workbench at a certain height, depending on the height of the worker. The vice is installed correctly if the hand of the worker, resting his elbow on the jaws of the vice, touches the chin with the ends of his fingers.

Hammers must be firmly mounted on handles made of hardwood.

The end of the working part of chisels and crossbars must be sharpened well at a certain angle. From the upper end of the chisel, the crosspiece, as well as the bit and drift, the formed burrs should be removed, which, flying off when the hammer hits, can cause injury.

Wooden file handles must be reinforced with metal rings that protect the handles from splitting and allow them to be placed more tightly on the file shanks.

When preparing a hacksaw for work, you should correctly (the hacksaw teeth should be directed forward) install the blade into the hacksaw machine and tighten the thumb well so that the blade does not bend when cutting.

When performing work directly at the car, the car mechanic's workplace is a maintenance or repair station.

Both when performing work on a workbench and directly at the car, its organization is important.

Before starting work, a car mechanic must receive an order to perform it. The work order indicates what work needs to be done, the time limit and the price. The spare parts or materials required to complete the work are issued from the warehouse.

If the car mechanic himself needs to make a new part, he is given a drawing or a sample of the part. Having received a task (order) for work, a car mechanic must first of all prepare the tools, devices and materials necessary to complete the task, and correctly arrange them on the workbench or near the car.

Each tool must be placed in a specific place so that any item can be taken immediately, without making unnecessary movements and without spending extra time searching for it. It is advisable to train yourself to pick up an instrument without looking.

Tools that are taken with the left hand are placed on the left, and those that are taken with the right hand are placed-- on right. Everything that is used more often is placed closer to you. Items not related to the work being performed are removed from the workbench.

Job responsibilities

An auto electrician must:

1.Come to work 10 minutes before the start of the working day, change into clean work clothes, prepare workplace to work.

2. Carry out electrical equipment repairs and vehicle diagnostics, according to the instructions received from the shift foreman:

Carry out diagnostics of electrical equipment using an existing computer to diagnose the generator and engine;

If necessary, disassemble and reassemble electrical equipment to repair the starter;

Place the car on a lift to identify and eliminate chassis faults;

If necessary, disassemble and repair vehicle components to perform gearbox repairs;

Diagnose mechanical engine faults, disassemble and repair the engine;

Hand over the finished car to a replacement technician.

3. Carry out a full list of ordered work on the car.

4. In all cases of relationships with clients, act technologically, observing the established standards for the relationship between auto center employees and clients.

5. Prevent the emergence of conflict issues with clients of the auto center, trying in all cases to satisfy the requirements of clients and maintain their friendly attitude towards the auto center.

6.Ensure proper safety of vehicles accepted for service.

7. Monitor the working condition of tools and equipment; use them correctly.

8.If any malfunctions are detected that affect the safe operation of the vehicle, bring this information to the receptionist and the client.

9. Observe safety precautions, fire safety rules, industrial sanitation standards.

10. Treat the issued protective clothing with care.

11.Ensure quality of work and rhythm.

2.2 Tools and devices used in the maintenance and repair of the contact ignition system

To work with automotive wiring, you need high-quality auto electrician tools and instruments for testing and diagnosing electrical equipment and batteries.

A measuring probe is a tool for measuring very small distances using the contact method, which is a set of thin metal plates of various thicknesses with a size printed on them (plate thickness). The plates of the set are inserted into the gap until the next thickest plate no longer fits into the gap being measured.

Flat measuring probes

Flat measuring probes are used to control gaps between planes.

The probe looks like a plate of a certain thickness.

Measuring probes are manufactured with a thickness of 0.02 to 1 mm.

Measuring probes are produced in the form of sets of measuring plates of different thicknesses in one holder.

Probes can be used separately or in various combinations.

Technical characteristics of flat measuring probes:

No. of probe plates

	nominal thicknesses, mm

Fig. 2.2.2 Electrical probe for checking electrical circuits on vehicles, for 6-12 and 24 V.

With test tip, protective cap, alligator clip cable.

Length 120 mm

Fig 2.2.3 Pliers

Fig 2.2.4 Combination wrenches

Fig 2.2.5 Screwdriver set

How efficiently and safely a screwdriver works every day depends primarily on the quality of the tool. Not only the use of high-quality materials, but also the shape of the tool itself is of particular importance to ensure that the hand always has a strong grip on the tool.

Fig 2.2.6 Auto electrician set 226 items

1 - Pliers for stripping wires and crimping terminals 5 functions. 225mm (TCP-10353)

1 - Phillips screwdriver VDE PH1 x 80 mm

1 - Slotted screwdriver VDE SL0.8 x 4.0 x 80 mm

1 - Probe 6-12-24V

1 - Fuse puller

1 - Brush for battery terminals

Fuse set - 5A, 7.5A, 10A, 15A, 20A, 25A, 30A

Fuse set 6.35*32 mm (glass) - 5A, 10A, 15A

Euro fuse set - 8A, 10A, 16A

1 - Electrical tape 19 mm x 9 m

1 - Wire 1.25 mm² x 1.5 m

Set of terminals (fork, ring, bayonet)

Set of heat-shrinkable connecting sleeves

Set of heat shrink sleeves - W10 x 50mm, W5 x 50mm, W3 x 50mm

Set of plastic clamps - 2.5 x 100 mm, 2.5 x 160 mm, 3.6 x 200 mm

9 - Car lamps

1 - Wire with alligator clips

Quantity per box: 12 pcs; Net weight: 1.11 kg; Gross weight: 1.9 kg; Volume: 0.005 m

Fig 2.2.7 Multitestor

2.3 List of work performed in the scope of daily maintenance (ETO), TO-1, TO-2 for the contact ignition system

Maintenance elements of ignition systems (distributor breaker, coil, switch and spark plugs) are carried out during each regular TO-2 vehicle with in-depth diagnostics of the technical condition.

In progress daily maintenance and maintenance-1 check the serviceability of the ignition switch, the reliability of electrical contacts, the condition of high-voltage wires and their insulation, and the fastening of all ignition devices. It is necessary to systematically lubricate the drive roller bearings, parts of the centrifugal ignition timing regulator, the axis of the moving contact and cam clutch, and the felt cam wick.

In the contact ignition system, burning and electrical erosion of the breaker contacts occurs, which increases the resistance in the primary circle of the induction coil and reduces the angle of the closed state of the contacts. To eliminate these shortcomings, you should promptly clean them from carbon deposits and dirt and adjust the gap between them.

During operation, it is necessary to keep high-voltage parts of the ignition system clean and prevent moisture, dust and dirt from getting on them, which can lead to partial shunting and loss of current, breakdown of high-voltage parts or surface overlap.

Spark plugs are unscrewed during TO-2 with a special key, after cleaning the socket with compressed air, and check for cracks and carbon deposits on the insulator. The gap between the electrodes is checked with a round feeler gauge and adjusted by bending the side electrode.

It is prohibited to burn out spark plugs, as this will cause microcracks to appear on the insulator, which will lead to deterioration in performance and failure of the spark plugs.

During maintenance, you should check whether the wires that connect to the terminals of the ignition coil, additional resistance and transistor switch are mixed up, which can lead to damage to the latter

2.4 Possible faults ignition systems

No spark
1). The ignition distributor is faulty	Find the cause and fix the problem.
2). Ignition coil is faulty	Replace with a new one.
3). The ignition switch is faulty	Check the lock and replace the lock contact device.
4). The spark plugs are out of order	Clean or replace spark plugs.
Interruptions in engine operation
1). Distributor faulty	Check and repair the damage.
2). Poor contact in the primary circuit	Eliminate the defect.

4). Ignition coil malfunction	Check or replace.
5). Cracks in the distributor cap	Replace the cover.
6). Dirty or wet distributor cap contacts or wires	Clean and dry contacts or wires.
7). Incorrect contact gap	Adjust the gap (0.35-0.45 mm).
8). Capacitor broken	Replace.
9). The spark plug is faulty: oily or burnt electrodes, incorrect gap size, cracks in the insulator	With the engine running, check the spark plugs. Unscrew the faulty spark plug and clean it from carbon deposits. Replace the spark plug with a crack in the insulator.
Interruptions in one of several engine cylinders
1). Burning and contamination of breaker contacts	Eliminate the defect.
2). Violation of the gap between the breaker contacts	Set the gap within 0.35-0.45 mm.
3). High-voltage wires are loose or damaged	Reconnect or replace wires.
The engine suddenly stops working and cannot be started
1). Capacitor broken	Check and correct the defect.
2). Broken contact in the ignition power supply circuit	Inspect the contact points of the wires.
The engine only runs when starting until the starter is turned off.
1). Open circuit in the additional resistor of the ignition coil	Replace the resistor.

2.5 Setting the ignition timing

Fig. 2.5.1 Distributor (with removed runner and cover) of engine mod. 331 and 3317

Fig. 2.5.2 Installation duplicate marks on the flywheel and clutch housing of the engine mod. 331 and 3317

Installation of ignition on engines mod. 331 and 3317 are produced when the new car has a mileage of 1.5 thousand km. and subsequently every 15 thousand km.

For engines mod. 331 and 3317 ignition distributors 47.3706 are installed.

Checking the condition of the working surface of the breaker contacts, cleaning them, and lubricating the distributor are carried out similarly to the ignition distributor of an engine mod. 2106 every 15 thousand km of vehicle mileage. Additionally, it is necessary to lubricate the cam bushing by first removing the rotor and the felt washer under it.

Adjusting the gap between the breaker contacts

1. Rotate the distributor shaft so that the gap between the contacts becomes maximum.

2. Loosen screws 3 (Fig. Distributor (with removed slider and cover) of engine mod. 331 and 3317) securing contact post 8.

3. Insert a screwdriver into groove 9 and, moving closer (or removing) contact post 8 to (from) contact(s) on breaker lever 1, set the gap between the contacts to 0.45 ± 0.05 mm.

4. After completing the adjustment, tighten screws 3.

Setting the ignition timing with the following options:

A) The distributor was not removed from the engine

1. Remove the distributor cap.

2. Rotating the crankshaft, bring the current carrying plate of the runner to the low-voltage terminal of the distributor (to the high-voltage terminal to the spark plug of the first cylinder on the distributor cover).

3. Continuing to slowly rotate the crankshaft, align mark 3 on the crankshaft pulley with the alignment pin 1 on the lower cover of the timing sprockets (duplicate mark 3 (Fig. Installation duplicate marks on the flywheel and clutch housing of the engine mod. 331 and 3317) on the flywheel should coincide with mounting lug 2 on the clutch housing). In this case, the piston of the first cylinder will be in the compression stroke, and the ignition timing will be 10° (before TDC).

4. Connect a test lamp to the low voltage terminal of the distributor 5 (see Fig. Distributor (with the slider and cover removed) (you can use any car lamp) and to ground and turn on the ignition. Turn the distributor housing counterclockwise until the breaker contacts close (the lamp goes out).

5. Press the slider clockwise with your finger and slowly turn the distributor body in the same direction until the warning light comes on.

6. Check the accuracy of setting the breaker contacts to open by pressing the cam clockwise and at the same time lightly pressing the lever against it with your finger. In this case, the control lamp will either go out or the glow of its filament will decrease.

7. Tighten nut 6 securing the distributor shank to the drive housing.

8. Place the plastic cover on the distributor and secure it with two spring latches.

9. Insert the high-voltage wires coming from the spark plugs in accordance with the order of operation of the engine cylinders and taking into account the direction of rotation of the distributor rotor. Install the tip of the high-voltage wire from the spark plug of the first cylinder in the terminal socket of the distributor cover, located above the low-voltage terminal in the housing.

10. Insert the high-voltage wire coming from the ignition coil into the central socket of the cover until it stops.

B) The distributor was removed from the engine, the crankshaft was turned

1. Unscrew the spark plug of the first cylinder, close the spark plug hole in the cylinder head with a plug made of crumpled paper and rotate the crankshaft until this plug is pushed out, thus determining the beginning of the compression stroke in the first cylinder.

2. Remove the distributor cap.

3. Rotating the distributor shaft, bring the current-carrying plate of the runner to the low-voltage terminal.

4. Insert the distributor shank into the distributor drive housing on the engine.

5. Rotate the distributor shaft by the slider until the floating clutch pins align with the shaft groove in the distributor drive housing and engage them. It should be taken into account that the spikes of the floating clutch of the distributor roller and the counter groove in the drive are shifted to the side relative to the axis of symmetry. Therefore, it will not be possible to install the distributor without first turning the slider with the current carrying plate towards the low-voltage terminal. Next, the ignition installation is carried out in accordance with paragraphs 3-10.

Direction of rotation of the rotor of the ignition distributor 47.3706 engines mod. 331 and 3317 counterclockwise.

The operating order of engine cylinders is 1-3-4-2.

To install an earlier ignition, the ignition distributor housing must be turned clockwise, and a later one - counterclockwise

Conclusion

The purpose of this thesis is to study the technology of repairing the ignition system.

The thesis consists of an explanatory note and a stand with installed devices of the contact ignition system.

In the explanatory note of the diploma project, the main part discusses:

General description of the ignition system design;

Designs of repair and diagnostic devices are proposed.

The special part of the thesis examines:

Stand with devices connected in electrical circuits low and high voltage;

The main devices intended for repairing the ignition system are considered.

The topic of this thesis is very relevant and has broad practical and theoretical significance.

Used in the diploma modern methods studying, analyzing and systematizing the material.

Consequently, the goals set for the thesis have been achieved.

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Operating principle of the contact ignition system

1. No spark at the spark plugs

2. Engine runs rough

Ignition system

Classification of ignition systems

Ignition system components

Magneto

Contact ignition system

Contactless ignition

Electronic ignition

Send your good work in the knowledge base is simple. Use the form below

Ignition system

Flat measuring probes

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