An Overview Study of Camless Combustion Engines

The internal combustion engine (ICE) finds its place in the market with latest design modifications in various components to improve efficiency, economy and overall performance. However, one component has remained unchanged in the internal combustion engine development i.e., the camshaft, has been the primary means of controlling the valve actuation and timing, and therefore, influencing the overall performance of the vehicle. Camless technology is capturing the future of internal combustion engines. It has been known to man that if valves could be controlled independently in an Internal Combustion Engine then there would be benefits like increased power, reduced emissions and increased fuel economy. In the camless technology valve motion is operated by valve actuators of electro-mechanical and electro-hydraulic type. In this paper we compare camless valve operation with conventional valve operation and we deal with the valve actuating mechanisms of camless engine by considering the electromechanical and electrohydraulic actuators as the important types of actuating valves in camless engines.

THE DESIGN OF HYBRID ELECTROMECHANICAL VALVE ACTUATOR: EFFECTS OF CONSTRUCTION PARAMETERS

In this paper, a novel modified cylindrical core, axis symmetric, low-inductance, hybrid permanent magnet (PM)/electromagnet (EM) magnetomotive force (MMF) actuator is proposed for variable valve timing camless engine. The new design provides large magnetic force with low energy consumption (startup and holding force), permanent magnet demagnetization isolation and improved transient response. The design and construction parameter sensitivity simulation results confirm the force of approximately 200 N (in the presence of coil current) and 500 N (in the absence of coil current) at equilibrium position and armature seat, respectively. An improvement in transition time due to low coil inductance, flexible control with parallel coils and 41.96% low energy dissipation is observed.