Gasoline Fuel Injection System K Jetronic

Gasoline Fuel Injection System K Jetronic-PDF Download

  • Date:28 Jun 2020
  • Views:4
  • Downloads:0
  • Pages:42
  • Size:1,010.64 KB

Share Pdf : Gasoline Fuel Injection System K Jetronic

Download and Preview : Gasoline Fuel Injection System K Jetronic


Report CopyRight/DMCA Form For : Gasoline Fuel Injection System K Jetronic


Transcription:

Published by,Robert Bosch GmbH 2000,Postfach 30 02 20. D 70442 Stuttgart,Automotive Equipment Business Sector. Department for Automotive Services,Technical Publications KH PDI2. Editor in Chief,Dipl Ing FH Horst Bauer,Editorial staff. Dipl Ing Karl Heinz Dietsche,Dipl Ing BA J rgen Crepin.
Presentation,Dipl Ing FH Ulrich Adler,Joachim Kaiser. Berthold Gauder Leinfelden Echterdingen,Translation. Peter Girling,Technical graphics,Bauer Partner Stuttgart. Unless otherwise stated the above are all,employees of Robert Bosch GmbH Stuttgart. Reproduction copying or translation of this, publication including excerpts therefrom is only to.
ensue with our previous written consent and with,source credit. Illustrations descriptions schematic diagrams, and other data only serve for explanatory purposes. and for presentation of the text They cannot be, used as the basis for design installation or scope. of delivery We assume no liability for conformity of. the contents with national or local legal regulations. We are exempt from liability,We reserve the right to make changes at any time. Printed in Germany,Imprim en Allemagne,4th Edition February 2000.
English translation of the German edition dated,September 1998. K Jetronic, Since its introduction the K Jetronic Combustion in the gasoline engine. gasoline injection system has pro The spark ignition or. ved itself in millions of vehicles Otto cycle engine 2. This development was a direct result Gasoline engine management. of the advantages which are inherent Technical requirements 4. in the injection of gasoline with Cylinder charge 5. regard to demands for economy of Mixture formation 7. operation high output power and Gasoline injection systems. last but not least improvements to Overview 10,the quality of the exhaust gases K Jetronic. emitted by the vehicle Whereas the System overview 13. call for higher engine output was the Fuel supply 14. foremost consideration at the start of Fuel metering 18. the development work on gasoline Adapting to operating conditions 24. injection today the target is to Supplementary functions 30. achieve higher fuel economy and Exhaust gas treatment 32. lower toxic emissions Electrical circuitry 36, Between the years 1973 and 1995 Workshop testing techniques 38. the highly reliable mechanical multi,point injection system K Jetronic.
was installed as Original Equipment,in series production vehicles Today. it has been superseded by gasoline,injection systems which thanks to. electronics have been vastly im,proved and expanded in their func. tions Since this point the K Jetronic,has now become particularly impor. tant with regard to maintenance and,This manual will describe the.
K Jetronic s function and its particu,lar features. Combustion in,the gasoline,Combustion in,the gasoline engine. combustion process pressurizes the, The spark ignition cylinder propelling the piston back down. or Otto cycle engine exerting force against the crankshaft and. performing work After each combustion,stroke the spent gases are expelled from. Operating concept the cylinder in preparation for ingestion of. The spark ignition or Otto cycle1 a fresh charge of air fuel mixture The. powerplant is an internal combustion IC primary design concept used to govern. engine that relies on an externally this gas transfer in powerplants for. generated ignition spark to transform the automotive applications is the four stroke. chemical energy contained in fuel into principle with two crankshaft revolutions. kinetic energy being required for each complete cycle. Today s standard spark ignition engines,employ manifold injection for mixture.
formation outside the combustion,The four stroke principle. chamber The mixture formation system The four stroke engine employs flow. produces an air fuel mixture based on control valves to govern gas transfer. gasoline or a gaseous fuel which is charge control These valves open and. then drawn into the engine by the suction close the intake and exhaust tracts. generated as the pistons descend The leading to and from the cylinder. future will see increasing application of, systems that inject the fuel directly into the 1st stroke Induction. combustion chamber as an alternate 2nd stroke Compression and ignition. concept As the piston rises it compresses 3rd stroke Combustion and work. the mixture in preparation for the timed 4th stroke Exhaust. ignition process in which externally, generated energy initiates combustion via Induction stroke. the spark plug The heat released in the Intake valve open. Fig 1 Exhaust valve closed, Reciprocating piston engine design concept Piston travel downward. OT TDC Top Dead Center UT BDC Bottom Combustion none. Dead Center Vh Swept volume VC Compressed, volume s Piston stroke The piston s downward motion increases.
OT the cylinder s effective volume to draw,fresh air fuel mixture through the passage. s exposed by the open intake valve,UT Compression stroke. Intake valve closed,Exhaust valve closed,OT Piston travel upward. Combustion initial ignition phase,1 After Nikolaus August Otto 1832 1891 who. UT unveiled the first four stroke gas compression engine. 2 at the Paris World Exhibition in 1876, As the piston travels upward it reduces The ignition spark at the spark plug Otto cycle.
the cylinder s effective volume to ignites the compressed air fuel mixture. compress the air fuel mixture Just before thus initiating combustion and the. the piston reaches top dead center TDC attendant temperature rise. the spark plug ignites the concentrated This raises pressure levels within the. air fuel mixture to initiate combustion cylinder to propel the piston downward. Stroke volume Vh The piston in turn exerts force against. and compression volume VC the crankshaft to perform work this. provide the basis for calculating the process is the source of the engine s. compression ratio power, Vh VC VC Power rises as a function of engine speed. Compression ratios range from 7 13 and torque P M, depending upon specific engine design A transmission incorporating various. Raising an IC engine s compression ratio conversion ratios is required to adapt the. increases its thermal efficiency allowing combustion engine s power and torque. more efficient use of the fuel As an curves to the demands of automotive. example increasing the compression ratio operation under real world conditions. from 6 1 to 8 1 enhances thermal, efficiency by a factor of 12 The latitude Exhaust stroke. for increasing compression ratio is Intake valve closed. restricted by knock This term refers to Exhaust valve open. uncontrolled mixture inflammation charac Piston travel upward. terized by radical pressure peaks Combustion none,Combustion knock leads to engine. damage Suitable fuels and favorable As the piston travels upward it forces the. combustion chamber configurations can spent gases exhaust out through the. be applied to shift the knock threshold into passage exposed by the open exhaust. higher compression ranges valve The entire cycle then recommences. with a new intake stroke The intake and, Power stroke exhaust valves are open simultaneously.
Intake valve closed during part of the cycle This overlap. Exhaust valve closed exploits gas flow and resonance patterns. Piston travel upward to promote cylinder charging and. Combustion combustion post combus scavenging,tion phase. Operating cycle of the 4 stroke spark ignition engine. Stroke 1 Induction Stroke 2 Compression Stroke 3 Combustion Stroke 4 Exhaust. management,engine management,Technical requirements Primary engine. management functions,The engine management system s first. Spark ignition SI and foremost task is to regulate the. engine torque engine s torque generation by controlling. all of those functions and factors in the, The power P furnished by the spark various engine management subsystems. ignition engine is determined by the that determine how much torque is. available net flywheel torque and the generated,engine speed.
The net flywheel torque consists of the Cylinder charge control. force generated in the combustion In Bosch engine management systems. process minus frictional losses internal featuring electronic throttle control ETC. friction within the engine the gas the cylinder charge control subsystem. exchange losses and the torque required determines the required induction air. to drive the engine ancillaries Figure 1 mass and adjusts the throttle valve. The combustion force is generated opening accordingly The driver exercises. during the power stroke and is defined by direct control over throttle valve opening. the following factors on conventional injection systems via the. The mass of the air available for physical link with the accelerator pedal. combustion once the intake valves,have closed Mixture formation. The mass of the simultaneously The mixture formation subsystem cal. available fuel and culates the instantaneous mass fuel. The point at which the ignition spark requirement as the basis for determining. initiates combustion of the air fuel the correct injection duration and optimal. mixture injection timing,Driveline torque factors,1 Ancillary equipment 1 1 2 3 4. alternator,a c compressor etc,4 Transmission,Air mass fresh induction charge. Combustion Engine Flywheel Drive, Fuel mass output torque output torque torque Trans force. Engine Clutch,Ignition angle firing point,Gas transfer and friction.
Ancillaries,UMM0545 1E,Clutch converter losses and conversion ratios. Transmission losses and conversion ratios, Ignition emissions control system Figure 2 The Cylinder. Finally the ignition subsystem de air entering through the throttle valve and charge. termines the crankshaft angle that remaining in the cylinder after intake. corresponds to precisely the ideal instant valve closure is the decisive factor. for the spark to ignite the mixture defining the amount of work transferred. through the piston during combustion, The purpose of this closed loop control and thus the prime determinant for the. system is to provide the torque amount of torque generated by the. demanded by the driver while at the engine In consequence modifications to. same time satisfying strict criteria in the enhance maximum engine power and. areas of torque almost always entail increasing, Exhaust emissions the maximum possible cylinder charge. Fuel consumption The theoretical maximum charge is. Power defined by the volumetric capacity,Comfort and convenience and.
Safety Residual gases,The portion of the charge consisting of. residual gases is composed of,The exhaust gas mass that is not. Cylinder charge discharged while the exhaust valve is. open and thus remains in the cylinder,Elements and. The gas mixture found in the cylinder The mass of recirculated exhaust gas. once the intake valve closes is referred to on systems with exhaust gas recircu. as the cylinder charge and consists of lation Figure 2. the inducted fresh air fuel mixture along The proportion of residual gas is de. with residual gases termined by the gas exchange process. Although the residual gas does not, Fresh gas participate directly in combustion it does. The fresh mixture drawn into the cylinder influence ignition patterns and the actual. is a combination of fresh air and the fuel combustion sequence The effects of this. entrained with it While most of the fresh residual gas component may be thoroughly. air enters through the throttle valve desirable under part throttle operation. supplementary fresh gas can also be Larger throttle valve openings to com. drawn in through the evaporative pensate for reductions in fresh gas filling. Cylinder charge in the spark ignition engine,1 Air and fuel vapor.
2 Purge valve,with variable aperture 2 3,3 Link to evaporative emissions. control system 1,4 Exhaust gas,5 EGR valve with 4 5. variable aperture,6 Mass airflow barometric pressure pU 11 12. 7 Mass airflow,intake manifold pressure ps 6 7 10,8 Fresh air charge 8. combustion chamber pressure pB,9 Residual gas charge 9.
combustion chamber pressure pB,10 Exhaust gas back pressure pA. UMM0544 1Y,11 Intake valve,12 Exhaust valve,Throttle valve angle. Gasoline are needed to meet higher torque on a supplementary EGR valve linking. engine demand These higher angles reduce the the intake and exhaust manifolds The. management engine s pumping losses leading to engine ingests a mixture of fresh air and. lower fuel consumption Precisely reg exhaust gas when this valve is open. ulated injection of residual gases can, also modify the combustion process to Pressure charging. reduce emissions of nitrous oxides NOx Because maximum possible torque is. and unburned hydrocarbons HC proportional to fresh air charge density it. is possible to raise power output by,compressing the air before it enters the. Control elements cylinder,Throttle valve Dynamic pressure charging.
The power produced by the spark A supercharging or boost effect can be. ignition engine is directly proportional to obtained by exploiting dynamics within. the mass airflow entering it Control of the intake manifold The actual degree of. This manual will describe the K Jetronic s function and its particu lar features The spark ignition or Otto cycle engine Operating concept The spark ignition or Otto cycle1 powerplant is an internal combustion IC engine that relies on an externally generated ignition spark to transform the chemical energy contained in fuel into kinetic energy Today s standard spark ignition engines

Related Books