Technology of maintenance and repair work of the fuel supply system of the car engin

Figure 1. Distributed spray system.
1-fuel tank; 2-electric pump; 3-fine cleaning filter; 4-Electronic Control Unit; 5-electromagnet forsunka; 6-driving trunk; 7-reduction valve;
8-input pipeline path; 9-drossel zaslonka condition sensor; 10-air consumption connector; 11 - probe in the form; 12-temperature sensor; 13-ignition distributor;
14-additional air regulator; 15-battery; 16-ignition lock.

The fuel is sucked out of the tank (1) with an electric gasoline pump (2). Then the oil is driven into the trunk (3) through a cleaning filter (6). In the trunk, the pressure difference is constantly maintained at the input and output of fuel into the forcible (7) by means of a reduction valve (5). Excess fuel returns from the reduction valve (7) to the tank.

From the fuel driving trunk, a separate electromagnetic forceps (5) is sent, which spray the fuel into the zone of the inlet valves. Air enters the cylinders, through the consumption meter (10) and through the input pipeline (3). The amount of air is adjusted through the drossel zaslonka. The electronic control system, which normalizes the fuel, is supplied by a current from the battery (15) and is connected to the chain by the ignition lock (16).
The air consumption meter (10) and the ignition distribution meter (shaft rotation frequency signal) are studied in the Electronic Control Unit (4) and pulses are released in accordance with the program included in it. These pulses control the opening of the farsunka valves and acquire a duration corresponding to each operating mode of the engine. The periodic supply of fuel with forsunka (1) will depend only on the open standing time of the forsunka Valve, since the reduction valve (5) holds the constant excess pressure of the fuel with an accuracy of 2 KPa in relation to the pressure of the air in the inlet pipe path.


Methods
The duration of spraying, depending on the temperature of the coolant (sensor 12), is corrected (straightened) with the control unit, the economizer effect in the acceleration mode and the thickening of the mixture are provided on the basis of the sensor (9) signals that are mechanically combined with the Drossel zaslonka axis.
The sensor also provides for a pair with a contact that signals to stop the fuel supply in the forced salt operation mode. Stopping fuel sending, while the frequency of revolutions in the closed position of the drossel zamlonkas decreases from about 1500 min–1, the fuel supply is connected again. Depending on the temperature regime of the engine, the threshold for stopping refueling is corrected.
In order for the reduction valve and forceps to work for a long time without damage, it is important to filter the fuel with good quality.
The measurement of air consumption is carried out by means of a thermoanemometer with high accuracy and allows the composition of the mixture to be kept in an unchanged state even when the atmospheric pressure changes[3]. A sensitive element made of thin platinum wire with a thickness of 70 µm is placed along the transverse cross-section of the input pipeline and connected to the resistance bridge chain. The thin wire is heated to a constant temperature of 150 degrees C. The greater the air consumption, the stronger the heat removal from the thin wire, consequently, the lower the temperature and resistance of the wire. The heating current increases. The thrust force, which is proportional to air consumption, is measured continuously through a set of resistances and determines the amount of air consumed. After the engine stops (thermoanemometer), the thin cable, according to the command of the control unit, heats up for a short time to high temperatures and is cleaned of impurities that can disrupt the air consumption signal [4].
The accuracy of rationing and the uniformity of sending fuel to the cylinders largely depend on the quality of the Forsaken. The principle drawing of electromagnetic forsunks is shown in Figure 2.