>> Power supply systems, managements of engine/decrease in toxicity of the fulfilled gases and production of the fulfilled gases
>> Power supply system of diesel engines
Power supply system of diesel engines
At operation of the diesel engine in its cylinders external air which is compressed to a high pressure is soaked up. Thus air temperature as a result of adiabatichesky heating rises to level 700-900°C, ignition of diesel fuel exceeding a point. Fuel is injected into the cylinder with some advancing and ignites. Thus, need for use of spark plugs disappears.
As well as on petrol models the power supply system consists of two paths: supply of fuel and supply of air; management of functioning of system carries out the special electronic module (ECM). In more detail the principle of functioning of a control system diesel engines/decrease in toxicity of the fulfilled gases is stated in the Section System of self-diagnostics of diesel models (see. A part of the Control system of the engine and decrease in toxicity of the fulfilled gases).
System of supply of air
The main features of a design of an inlet air path of the diesel engine considered in the real Management are use in it of the turbokompressor given in rotation by a stream of fulfilled gases, and lack of a drosselirovaniye on an admission (it is characteristic for the diesel engines equipped with TNVD of distributive type). The additional increase in a consumption of air of pressurization is provided at the expense of its thermal compression in the heat exchanger of an intermediate cooler (Intercooler).
Design of an inlet air path of the diesel engine
For rotation of the compressor of system of pressurization the stream of the fulfilled gases of the engine, submitted to the case of turbine assembly is used, - the driving wheel of the compressor is planted on one shaft with a wheel of the turbine and the rotation provides compression of air passing through an air purifier and its giving under a pressure in the inlet pipeline of the engine. Such design of the compressor guarantees immediacy of reaction of system of pressurization on change of loads of the engine, outright connected with intensity of release of the engine.
Two sensors are switched on in structure of a turbokompressor: temperatures (TA) and pressure of air of pressurization. On the basis of the analysis of the data arriving from these PCM sensors defines amount of air arriving in the engine.
Intermediate cooler (Intercooler)
Included in an inlet air path of the turbirovanny engine the heat exchanger of an intermediate cooler serves for compensation of effect of an adiabatichesky warming up of air forced by the compressor. The heat exchanger is established on an exit from the compressor and during movement of the car is continuously blown by a running stream of the air grasped by formed in a cover of a cowl by an air inlet, - when cooling air is compressed that in addition increases efficiency of functioning of system of pressurization.
||The heat exchanger of an intermediate cooler of system of pressurization is established on an exit from a turbokompressor.
System of supply of fuel
The system of supply of fuel of diesel engines differs high degree of reliability and at diligent performance of procedures of regular service with observance of requirements of Specifications of Head of the Power supply system, managements of engine/decrease in toxicity of the fulfilled gases and production of the fulfilled gases to type of used fuel should function regularly during all service life of the car.
As a result of long use internal components of nozzles can wear out. It will be correct to charge performance of regenerative repair of nozzles to specialists of car-care center.
Basic element of a fuel path of the diesel engine of considered models is the pump of a high pressure (TNVD) of distributive type (VE) with the electronic control, carrying out fuel absorption via the filter from the fuel tank located behind under the car and its dosed-out distribution through nozzles in chambers of combustion of the engine.
Scheme of the organization of system of supply of fuel of the diesel engine
Fuel pump of a high pressure (TNVD)
The principle of absorption and fuel compression in electronic TNVD is similar to a principle used in pumps of mechanical type. The main difference of the electronic pump is use instead of the centrifugal proof-reader of the moments of injection of an electronic regulator with a hummock drive (instead of lever).
onstruktsiya of electronic TNVD of distributive type
Electronic regulator (GE)
The executive GE mechanism is fixed on the regulator chamber in the top part of assembly of TNVD.
Design of an electronic regulator of TNVD of distributive type
The phenomenon of emergence of a magnetic field is put in a basis of functioning of a regulator when giving on a winding of the coil of an electric current. Intensity of an induced field will be directly proportional to force of a current passed through a winding that provides possibility of deployment of a rotor of a regulator in demanded situation with overcoming of effort developed by a returnable spring, - at the expense of rotation of a rotor controllable linear moving of the managing director of the coupling is provided.
||Principle of functioning of a regulator.
The magnetic filter a part of a regulator provides protection of working chambers of pump assembly against hit of extraneous subjects in them.
Valve of management of distribution of the moments of injection (TCV)
TCV is located between high-pressure head and low-pressure head chambers and provides pressure adjustment at the expense of opening when giving power supply.
When a food on the valve does not move, chambers remain isolated. Opening of TCV leads to their association, as a result the distributive piston is displaced under the influence of effort developed by a spring in the situation providing alignment of pressure, - correction of the moment of injection is carried out at the expense of a simultaneous povorachivaniye of the roller holder.
The sensor of position of the operating coupling (CSP)
The sensor is located in the top part of assembly of a regulator and delivers to ECM information on position of the operating coupling which moving leads to a povorachivaniye on a certain corner of a sensitive element of the sensor at the expense of change of a difference of induktivnost in its top and bottom windings. ECM compares the obtained data with demanded value and in case of need gives out command for performance of the corresponding adjustment by change of force of a current passed through windings.
The special fixed plate provides compensation of temperature changes of inductance.
Sensor of position of the distributive piston (TPS)
TPS is connected to the low-voltage party of the switching center, consists of the rod core and the reel and serves for ECM notification about moving of the distributive piston, - moving of the piston leads to change of inductance of the coil of the sensor as a result of the corresponding moving of the core.
Sensor of turns of TNVD (Np)
The Np sensor delivers to ECM information on TNVD turns. The sensor represents the solenoid reacting to passing by its magnet of each of the 4th teeths of the rotating alarm plate. Developed when passing by teeths through a magnetic field the alternating current will be transformed to the pulse signals which are given out on the module of management.