>> Power supply systems, managements of the engine/decrease of toxicity of the fulfilled gases and release of the fulfilled gases
>> The power supply system of diesel engines
The power supply system of diesel engines
The general information
At work 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 адиабатического heating rises to level 700-900С, ignition of diesel fuel exceeding a point. Fuel is injected into the cylinder with some advancing and ignites. Thus, necessity for use of spark plugs disappears.
As well as on petrol models the power supply system consists of two paths: givings of fuel and air giving; management of system functioning carries out the special electronic module (ECM). In more details the principle of functioning of a control system is stated by the diesel engine/decrease of toxicity of the fulfilled gases in Section System of self-diagnostics of diesel models (the Part of the Control system of the engine and decrease in toxicity of the fulfilled gases see).
System of giving of air
The main features of a design of an inlet air path of the diesel engine considered in the present Management are use in it турбокомпрессора, resulted in rotation by a stream of the fulfilled gases, and absence дросселирования on an admission (it is characteristic for the diesel engines equipped ТНВД of distributive type). The additional increase in the expense of air of pressurisation 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 pressurisation the stream of the fulfilled gases of the engine, submitted to the case of turbine assemblage is used, - the compressor driving wheel is planted on one shaft with a wheel of the turbine and the rotation provides compression of air passing through an air cleaner 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 pressurisation on change of loadings on the engine, outright connected with intensity of release of the engine.
Two gauges are included in structure турбокомпрессора: temperatures (TA) and pressure of air of pressurisation. On the basis of the analysis of the data arriving from given gauges PCM defines quantity of air arriving in the engine.
Intermediate cooler (Intercooler)
Included in an inlet air path турбированного the engine the heat exchanger of an intermediate cooler serves for effect indemnification адиабатического a warming up of air forced by the compressor. The heat exchanger is established on an exit from the compressor and during car movement is continuously blown by a running stream of air grasped formed in cover of a cowl by an air inlet, - at cooling air is compressed that in addition raises efficiency of functioning of system of pressurisation.
|The heat exchanger of an intermediate cooler of system of pressurisation is established on an exit from турбокомпрессора.
System of giving of fuel
The system of giving 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 the Head of the Power supply system, managements of the engine/decrease of toxicity of the fulfilled gases and release 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 atomizers can wear out. Performance of regenerative repair of atomizers will correctly charge to experts of car-care centre.
Basic element of a fuel path of the diesel engine of considered models is the high pressure pump (ТНВД) distributive type (VE) with the electronic control, carrying out всасывание fuel through the filter from the fuel tank located behind under the car and its dosed out distribution through atomizers in chambers of combustion of the engine.
The scheme of the organisation of system of giving of fuel of the diesel engine
The fuel pump of a high pressure (ТНВД)
The principle всасывания and fuel compression in electronic ТНВД 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 тросовым a drive (instead of lever).
онструкция electronic ТНВД distributive type
Electronic regulator (GE)
Executive mechanism GE is fixed on the regulator chamber in the top part of assemblage ТНВД.
Design of electronic regulator ТНВД of distributive type
The phenomenon of occurrence of a magnetic field is put in a basis of functioning of a regulator at 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 position with overcoming of effort developed by a returnable spring, - at the expense of rotor rotation controllable linear moving of the managing director муфты is provided.
|Principle of functioning of a regulator.
The magnetic filter a part of a regulator provides protection of working chambers of pump assemblage against hit in them of extraneous subjects.
The valve of management of distribution of the moments of injection (TCV)
TCV is located between высоконапорной and низконапорной with chambers and provides adjustment of pressure at the expense of opening at power supplies giving.
When a food on the valve does not move, chambers remain isolated. Opening TCV leads to their association, as a result the distributive piston is displaced under the influence of effort developed by a spring in the position providing alignment of pressure, - updating of the moment of injection is carried out at the expense of simultaneous поворачивания the roller holder.
The gauge of position of operating муфты (CSP)
The gauge is located in the top part of assemblage of a regulator and delivers ECM the information on position of the managing director муфты which moving leads поворачиванию on a certain corner of a sensitive element of the gauge at the expense of difference change индуктивностей in its top and bottom windings. ECM compares the obtained data to demanded value and in case of need gives out a command on performance of corresponding updating by change of force of a current passed through windings.
The special fixed plate provides indemnification of temperature changes of inductance.
The gauge of position of the distributive piston (TPS)
TPS it is connected to the low-voltage party of the switching centre, consists of the rod core and the reel and serves for notification ECM about moving of the distributive piston, - piston moving leads to change of inductance of the coil of the gauge as a result of corresponding moving of the core.
The gauge of turns ТНВД (Np)
Gauge Np delivers ECM the information on turns ТНВД. The gauge represents the solenoid reacting to passage by its magnet of each of 4 teeths of the rotating alarm plate. Developed at passage 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.