Continuously Variable Valve Mechanism for Spark Ignition Engines Using Linear Actuator

(Fundamental Consideration on Effect of Permanent Magnet Arrangement on Thrust Characteristics)

Abstract

In order to achieve higher performance in spark-ignition engines, it is required to control the intake and exhaust valves in stepless manner according to the engine speed. Our research group has been continuously studying the electromagnetic drive valve system using a linear actuator. In this report, we have designed a linear actuator with a dual Halbach array of permanent magnets in the stator to further increase the thrust of the linear actuator. The thrust characteristics of the proposed model were investigated using electromagnetic field analysis based on the finite element method. The analysis confirmed that the Halbach array concentrates the magnetic flux on the coil side, which generates Lorentz force.