Cylinder DeactivationAshish Patwal

Content

• Introduction• Cylinder deactivation mechanism• Methods used for cyllinder deactivation• Advantages• Disadvantages• Key players using cylinder deactivation• Future trends• Conclusion• Bibliography

Introduction

• Reducing fuel consumption• Cutting emission of green house gases• Reduce pumping losses• Cylinders are shutdown during light load• 8-25% reduction in fuel consumption

Introduction

Cylinder deactivation mechanism

• Coolant temperature, vehicle speed, engine load parameters.

• Disable inlet/exhaust valves, spark plug, fuel.• Disable after power stroke to have a gas

spring.• Lifter Oil Manifold Assembly, solenoid control

valves.

Methods used for cylinder deactivation

• Lifter Pin Control Mechanism (General Motors• Variable Profile Cam shaft (Lotus Automotive

System)• Active Valve Train Technology

Lifter Pin Control Mechanism

Components:• Electronic Control Module• Solenoid valves• Hydraulic subsytem• Lifter locking pin mechanism

Electronic Control Module• Measuring multiple instantaneous events• Control solenoid valve of the lifter pin

mechanism• Dynamic response for coordinating the

deactivation hardware with other engine control functions.

• Dynamic response:solenoid plunger, hydraulic subsytem, lifter locking pin

Solenoid Valve operation

Solenoid valve operation

• Control cylinder deactivation• Common port of the solenoid control valve

connected to the locking pins inside the valve lifter

• Common portEngine oil pressure: deactivationEngine sump: activation

Locking Pin Mechanism• Lost motion: engine oil pressure is applied

spring based locking pins inside the lifter• Deactivation is done on the camshaft of the

base circle.• Transition from v8 to v4 mode in one cycle.

Methods used in LPCM

• Cylinder bank control• Individual cylinder controlControl type: control algo in ecmCylinder deactivation: engine firing order

even firing orderCylinder mode: 2 cylinder deactivate at same

time

Bank mode

• Both cylinder from each bank switched same time.

• Two control valves required• Used in v engines, Boxer engines.• Switching window is half of the invidual

cylinder mode.

Advantages

• Increased fuel efficiency (10-20%) • Decreased emissions from deactivated

cylinders • Better breathing capability of the engine,

thereby reducing power consumed in suction stroke.

Disadvantages

• Engine balancing. • Increased cost of manufacturing• Overall increase in weight

Key Players

• GENERAL MOTORS: uses displacement on demand system which is said to save fuel by 20%• HONDA: Is conducting research to incorporate cylinder deactivation with its patented VTECH engine• PORSHE and SUBARU: Uses lotus designed various cam plus which works almost similar to V-tech

engine• Mercedes-Benz: optional on certain European market V-8s since 1998; U.S. market V-12 mileage

improved by a claimed 20 percent in 2001 and 2002 model years. Technology retired (in U.S.) with 2003 arrival of turbocharged V-12 engines.

• INA: German bearing and valve train specialist supplies switching lifters for DC’s 5.7L Hemi V-8 and GM’s 3.9L V-6.

• Eaton Automotive: supplies a portion of the LOMAs and switching lifters for GM’s 5.3L V-8. Also developing valve deactivation systems for light- and heavy-duty European diesel engines.

• Siemens-VDO Automotive: exploring cylinder deactivation for possible future use. Delphi Automotive: supplies a portion of the LOMAs and switching lifters for GM’s 5.3L V-8.

• Ford Motor Company: has investigated cylinder deactivation but no applications planned for near future.

• Nissan and Toyota: no near-term plans to implement cylinder deactivation.

Future Trends

• Research is under progress for a new technology named as Active Valve Train Technology, which uses valve controls with high speed hydraulic actuators there by eliminating the use of Cam shaft.

• Also a new technology called controlled auto ignition (CAI) which replaces the conventional spark plugs and fires at carefully timed moment to set the compressed charge of fuel alight.

Conclusion

• The yell for a pollution free environment can be seen even now with developed countries the number of norms like EUROIII is there in the present world itself and the number of vehicles is increasing even under developed countries are planning to impose such norms Future world demands automobile which burn less fuel .Cylinder deactivation seems to be a good answer to this problem.

Bibliography

• Automotive Industries Ltd • www.wikipedia.com • Research paper published by Quant Zheng , Delphi

Motors • Society of Automobile Engineers (SAE) Technical

papers