5.14.1. Features of a design
The power supply system structure includes elements of following systems:
– The giving of fuel including a fuel tank, an electrogasoline pump, the fuel filter, a regulator of pressure of fuel, pipelines and a fuel stage with atomizers;
– воздухоподачи into which enter the air filter, throttle knot, an idling regulator;
– Catching of steams of the fuel, consisting of an adsorber, the valve of a purge of an adsorber and connecting pipelines.
Functional purpose of system of giving of fuel — maintenance of giving of necessary quantity of fuel in the engine on all operating conditions. The engine is equipped by an electronic control system with the distributed injection of fuel. In system of the distributed injection of function смесеобразования and giving dispensing топливовоздушной mixes in engine cylinders are divided: air moves system воздухоподачи, consisting of throttle knot and an idling regulator, and necessary during each moment of work of the engine the quantity of fuel is injected by atomizers into an inlet pipe. Such way of management gives the chance to provide optimum structure of a gas mixture during each concrete moment of work of the engine that allows to receive the maximum capacity at is minimum possible expense of fuel and low toxicity of the fulfilled gases. Operates system of injection of fuel (and ignition system too) the electronic block continuously supervising by means of corresponding gauges loading of the engine, speed of movement of the car, a thermal condition of the engine, an optimality of process of combustion in engine cylinders.
The system of catching of steams of fuel prevents food leaving the system in atmosphere of steams of the fuel adversely influencing ecology of environment.
In system the method of absorption of steams is applied by a coal adsorber. It is established on the basis of a body on the right behind and connected by pipelines to a fuel tank and an inlet pipe. On an arm established on an inlet pipe, the electromagnetic valve of a purge of an adsorber which on signals of the block of engine management switches system operating modes is located.
Steams of fuel from a fuel tank on the pipeline constantly are taken away and collect in the adsorber filled with activated coal (адсорбентом). At engine work there is a regeneration (restoration) адсорбента an adsorber purge the fresh air arriving in system under the influence of depression, transferred on the pipeline from an inlet pipe in an adsorber cavity at valve opening. Size of opening of the valve and consequently, and intensity of a purge of an adsorber depend on an angle of rotation throttle заслонки and are defined by depression which arises in a cavity of an inlet pipe of the working engine.
Steams of fuel from an adsorber on the pipeline arrive in an inlet pipe of the engine and burn down in cylinders.
Malfunctions of system of catching of steams of fuel involve instability of idling, the engine stop, the raised toxicity of the fulfilled gases and deterioration of road performance of the car.
Fig. 5.21. The scheme of a contour of management of structure топливовоздушной mixes: 1 – the gauge of concentration of oxygen in the fulfilled gases (ljambda-probe); 2 – a final collector; 3 – the engine; 4 – an atomizer; 5 – the engine management block; 6 – каталитический neutralizer of the fulfilled gases
The basic gauge for maintenance of optimum process of combustion is the gauge of concentration of oxygen in the fulfilled gases (ljambda-probe). It is established in a final collector of the engine and together with the electronic block and atomizers forms a contour of updating of structure топливовоздушной a mix submitted to the engine (fig. 5.21). On signals of the gauge the engine management block defines quantity of not burnt down oxygen in the fulfilled gases and accordingly estimates a structure optimality топливовоздушной a mix arriving in cylinders of the engine during each moment of time. Having fixed a deviation of structure from optimum 1:14 (accordingly fuel and air), providing the most effective work catalytic neutralizer of the fulfilled gases, the block of management by means of atomizers changes mix structure. As a result the contour of management of structure топливовоздушной mixes is closed.
The fuel tank welded, stamped, is established under a body floor in its back part and attached by four bolts. That fuel steams did not get to atmosphere, the tank is connected by the pipeline to an adsorber. In фланцевое an aperture in the top part of a tank the electric fuel pump is established. From the pump fuel moves in the fuel filter established in подкапотном space on a board передка, and therefrom arrives in the fuel stage of the engine fixed on an inlet pipe. From a fuel stage fuel is injected by atomizers into an inlet pipe.
Топливопроводы power supply systems represent the tubes connecting among themselves various elements of system.
It is forbidden to replace steel pipelines with hoses, copper or aluminium tubes as only steel pipelines satisfy to working conditions at an elevated pressure and vibration.
Power supply system hoses are made on special technology from маслобензостойких materials. Application of the hoses different on a design from recommended, can lead to power supply system refusal, and in certain cases and to a fire.
In connections of pipelines with power supply system elements apply round sealing rings. Use of consolidations of other design is forbidden
The module of the fuel pump includes the electric pump and the gauge of the index of level of fuel.
The module of the fuel pump provides giving of fuel and is established in a fuel tank that reduces possibility of formation of steam stoppers as fuel moves under pressure, instead of under the influence of depression.
The fuel pump погружной, роторного type, with the electric drive. The pump of not folding design is not subject to repair, at failure it is necessary to replace it.
The fuel filter of thin clearing — полнопоточный, is fixed in an arm established on a board передка in подкапотном space. The filter not folding, consists of the steel case with a paper filtering element.
The fuel stage
2 (fig. 5.22
) represents a cast hollow detail with apertures for installation of atomizers 3, with a flange for installation of a regulator of pressure of fuel and with the union for joining топливопровода a
high pressure. Atomizers are condensed in apertures of a stage and in nests of an inlet pipe by rubber rings 4 and fixed by spring clamps 1. On a flange of a stage two screws attach a regulator of 5 pressure of fuel to which the pipeline fuel plum is attached. The stage with atomizers and a regulator in gathering is inserted by shafts of atomizers into apertures of an inlet pipe and fixed by two bolts.
|Fig. 5.22. A fuel stage: 1 – an atomizer clamp; 2 – a stage; 3 – an atomizer; 4 – a sealing ring of an atomizer; 5 – a regulator of pressure of fuel
) are attached to a stage from which to them fuel moves, and the sprays enter into apertures of an inlet pipe. In apertures of a stage and an inlet pipe of an atomizer are condensed by rubber sealing rings 1 and 3. The atomizer is intended for the dosed out injection of fuel in the cylinder of the engine and represents the high-precision electromechanical valve. Fuel under pressure arrives from a stage on channels in the atomizer case to запорному
to the valve. The spring draws in a needle запорного the
valve to конусному
to an aperture of a plate of a spray, keeping the valve in the closed position. The pressure submitted from the block of engine management through штекерные
conclusions 2 on winding of an electromagnet of an atomizer, creates in it a magnetic field involving the core together with a needle запорного
of the valve in an electromagnet. Конусное the
ring aperture in a spray plate opens, and fuel is injected through диффузор
spray cases into the inlet channel of a head of the block of cylinders and further in the engine cylinder. After the termination of receipt of an electric impulse the spring returns the core and a needle запорного the
valve in an initial condition — the valve is locked. The quantity of fuel injected by an atomizer, depends on duration of an electric impulse.
|Fig. 5.23. An atomizer of system of injection of fuel: 1 – the bottom sealing ring; 2 – штекерные conclusions of a winding of an electromagnet; 3 – the top sealing ring
The regulator of pressure of the fuel, established on a fuel stage, supports constant pressure of fuel in the central channel of a stage on all power setting. Regulation of pressure of the fuel submitted to atomizers, is based on a principle of tracking value of pressure difference in a stage and an inlet pipe which under any conditions should make not less than 300 кПа (3,0 kgs/sm2). Giving of the electric fuel pump more than it is necessary for maintenance of working capacity of system. Therefore at work of the engine by means of a regulator of pressure the fuel part constantly merges through the return pipeline in a fuel tank. Depending on depression in an inlet pipe the pressure regulator reduces or increases plums of excessive fuel, supporting constant pressure in a stage.
The pressure regulator represents the closed cavity divided by a diaphragm on vacuum and fuel chambers.
The vacuum chamber is informed through a vacuum hose with an inlet pipe of the engine, fuel — through the channel in the case of a regulator with a cavity of a fuel stage. In an operating time of the engine under the influence of a spring the regulator valve is closed, if pressure difference in an inlet pipe and a fuel stage no more than 0,3 МПа. Plum of fuel is not present the return — pressure in топливопроводе starts to raise. At pressure difference from above 300 кПа (3,0 kgs/sm2) the regulator diaphragm caves in and between the valve and its saddle the backlash through which in other channel of a regulator connected to the drain pipeline, excessive fuel merges is formed — pressure decreases. At increase in loading of the engine working at the big opening throttle заслонки, the fuel expense increases also pressure in a fuel stage falls. Simultaneously with it depression in an inlet pipe decreases. The spring presses the valve of a regulator of pressure to a saddle, fuel plums in a fuel tank stops — pressure raises. These processes repeat continuously therefore in a fuel stage constant pressure is supported.
The air filter is established in the right forward part of a motor compartment on an engine mudguard. The bottom branch pipe of the filter is inserted into an air line of the muffler of noise of the admission established under the right forward wing.
The filter is connected rubber goffered воздухоподводящим by a sleeve to throttle knot.
Filtering element of the air filter paper, flat, with the big area of a filtering surface.
The throttle knot represents the elementary regulating device and serves for change of quantity of the basic air submitted to inlet system of the engine. It is established on an entrance flange of an inlet pipe. The formed rubber sleeve fixed by a collar and connecting throttle knot with the air filter is put on an entrance branch pipe of throttle knot.
In the case of throttle knot the aperture for a supply of additional air to an idling regulator is executed.
|Fig. 5.24. Throttle knot: 1 – the gauge of position throttle заслонки; 2 – an idling regulator; 3 – throttle заслонка; 4 – sector of a drive throttle заслонки; 5 – the case of throttle knot
In the case 5 (fig. 5.24
) it is established turning on an axis заслонка
3. On one end of an axis the gauge of 1 position throttle заслонки
control systems of the engine, on other — sector 4 to which the cable of a drive throttle заслонки
is attached is established. On the case 5 the regulator 2 idlings which is dosing out a stream of air at closed throttle заслонке
In the air filter there is no device of seasonal adjustment, therefore the throttle knot is equipped by the system of heating preventing an icing throttle заслонки in a cold season and connected to system of cooling of the engine by hoses.
While in service the throttle knot does not demand service and adjustment, watch only a condition of rubber consolidations to avoid подсоса air.
The idling regulator supports the set frequency of rotation of idling of the engine at completely closed throttle заслонке during its start-up, warming up and at loading change at auxiliaries inclusion.
The regulator changes quantity of the additional air submitted to inlet system besides throttle заслонки, and represents the electromechanical valve attached by two bolts to a flange of the case of throttle knot. Executed in a flange of throttle knot channels and a saddle of the valve of a regulator form system of giving of additional air, passing throttle заслонку.
Fig. 5.25. An idling regulator: 1 – the valve; 2 – the regulator case; 3 – a winding статора; 4 – the running screw; 5 – штекерный a winding conclusion статора; 6 – the ball bearing; 7 – the winding case статора; 8 – a rotor; 9 – a spring
The engine management block, having processed signals from gauges, defines necessity of opening of the valve 1 (fig. 5.25) a regulator and transfers impulses on штекерный a conclusion of 5 windings 3 статора a regulator. At each operating impulse the rotor 8 turns on a certain corner, moving by means of the running screw 4 valve 1 concerning a saddle. In an inlet pipe through channels in throttle knot additional air arrives. Defining depression in an inlet pipe of the engine, the management block aspires to support it at the set level, periodically opening and closing the valve of a regulator of idling. It gives the chance to provide giving of constant quantity of additional air for maintenance of constant frequency of rotation of idling. Changing size of opening and closing of the valve of a regulator, the management block compensates substantial growth or reduction of quantity of the submitted air, caused it подсосом through not tight inlet system or, on the contrary, a contamination of the air filter.
Inclusion of additional units causes increase in loading of the engine, accompanied by decrease in frequency of rotation of idling and change of depression in an inlet pipe that also is compensated by the block of management by means of a regulator.