A novel electromagnetic latching device for variable valve timing in automotive engine

One of the most promising ways to improve fuel economy, reduce CO2 emissions and increase torque output is to achieve variable valve timing (VVT). Some of the devices developed in the past years include mechanical, hydraulic, motor-driven and electromagnetic actuators. Existing most advanced system is an electromagnetic actuator using solenoids to activate engine valves. It, however, needs the current continuously in all operation period and has difficult starting problem resulting in low power efficiency. In this paper, we propose a novel electromagnetic valve drive system, and discuss the design, finite element analysis and construction of the experimental apparatus.