Durability and Reliability Demonstration for Switching Roller Finger Follower in Cylinder Deactivation Systems

Overview of the potential and limitations of cylinder deactivation

“…The primary measurable factor for durability testing was lash increase. High load system and switching durability testing showed that the lash increase maintained a greater than 70% and 50% margin to the target after completing one life [95]. The system was proven to be robust to a 200,000-mile target.…”

“…The switching pressure port is connected to the oil control valve. When no electrical signal is sent to the oil control valve, the pressure at the switching port is regulated to 0.2-0.4 bar [95]. If the cylinder should be deactivated, an electrical signal from the ECU triggers the oil control valve to open the switching pressure port.…”

“…All the switching mechanisms need to pass fatigue and durability tests. The switchable roller finger follower mechanism was tested on a 3.6 l V6 and a 2.5 l in-line 4-cylinder engine [95].…”