Camless engines eliminate mechanical linkages like camshafts that traditionally open and close intake and exhaust valves. Instead, camless engines use electro-hydraulic or electromechanical systems to provide infinite control over valve timing, lift, and duration. This allows for greater engine efficiency and power. Sensors detect operating conditions and an electronic control unit actuates solenoids and hydraulic systems to optimize valve behavior for each situation. While camless engines are more expensive and complex than traditional designs, their performance advantages are expected to lead to their increased adoption over time.

1. Camless
Engines
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2. Introduction
Thenew emerging technology for automotivetechnology arethe
Camlessenginewhich theenginedoesnot havecamshaft to lift theboth
intakeand exhaust valve.

3. CAMS
• Control thebreathing channels(valves) of an IC engine
• Connected to camshaft which isoperated by crankshaft
• Camspush open valvesat proper time& guidetheir closure
• But they areinflexibleexcept VTEC & VVT-I
• Engineerscould not vary timing, lift & duration of valveopening infinitely

4. CAMLESS ENGINES
• Eliminated mechanical linkages
• Could provideinfinitevariation of valveparameters
• It can makeenginesclean, efficient & responsive

5. Working Of Conventional Engines
• Thecrankshaft turnscamshaft which operatesvalvesby mechanism
• Spring bringsback valveto initial position
• Timing of enginevalvesdependson shapeof cams

6. Conventional Engine Valves

7. • Engineersmust design camsin thedevelopment stages
• Thisdesign compromisesb/n enginepower & fuel efficiency
• Considering thiscompromiseautomobilecompaniesbrought variable
valvetiming mechanisms
• But iseffectswerelimited

8. Camless engines overview
• Main sensors-
 Engineload sensor Exhaust gassensor
 Valveposition sensor Enginespeed sensor
ELECTRONIC
CONTROL UNIT
SENSORS ACTUATORS

9. • Sensorssenseparameters& send signalsto ECU
• ECU containsmicroprocessorswith associated software
• ThisECU controlstheactuatorsto work according to requirements

10. Actuators
• It isaelectro-hydraulic camlessvalvetrain (ECV)
Useselastic property of compressed hydraulic fluid which actslikea
liquid spring, accelerates& deceleratesthevalves

11. Hydraulic pendulum
• Involvesconversion of PE to KE and back to PE with minimum
energy loss
• During acceleration of valvesPE isconverted to KE
• During deceleration of valveenergy of moving valveisreturned to
fluid

12. Detailed view of Hydraulic Pendulum

13. Operation of hydraulic pendulum

16. • Lift, timing & duration of valveopening isvaried by controlling
solenoid valves
• Thisisdoneby ECU when signalsaresent from thesensors

17. Modifier Rod
• Used to impart
 Unequal lift to thepaired valves
 Zero motion to any valve

18. Modifier Rod Operation

20. Advantages
• Enablesthedevelopment of higher torquethroughout theentirerev range
which in turn improvesfuel economy
• Cylinder Deactivation can beachieved during theidling phase
• Exhaust gasrecirculation isimproved
• Reducesfriction losses
• Reducestheinertiaof moving parts

21. Resultant Advantages
• Better fuel economy- 7 to 10 % increase
• Higher torque& power- 10 to 15 % increase
• Lower exhaust emissions- EGR system iseliminated sinceEGR effect
occurson itsown & thusreducesNOx emissions
• Reduction in size& weight

22. Disadvantages
• High Cost
• Increased power consumption
• Air gap between thesolenoidsmay demand ahigher magnitudeof
current during certain periods
• Thecontrol strategy for valveseating velocity needsto bemodified

23. Conclusion
Even though somedisadvantagesarepresent, wecan expect
electrohydraulic & electromechanical valvesto replacethe
conventional camshaft technology.

24. References
• http://www.cvel.clemson.edu/auto/AuE835_Projects_2011/Shroff_project.h
• http://en.wikipedia.org/wiki/Camless
• http://www.autospeed.com/cms/article.html?&A=0910

25. Thanks
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