Tracking Control of Engine Valve

• Main Authors: Je-Bin Hung, 洪哲彬
• Other Authors: 陳明新
• Format: Others
• Language: en_US
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/13802873120194995864

碩士 === 國立臺灣大學 === 機械工程學研究所 === 95 === The intake/exhaust valve is driven by the camshaft with constant angular velocity while the spark-ignition engine is in operation. Hence, the opening/closing timing of valves is unable to adjust according to engine speed. As a result, the engine has optimum efficiency only at certain engine speeds. Variable valve timing system can change the timing of valve in compliance with the engine speed so that engine’s optimal efficiency can be maintained at all speed. Research shows that such a proved effective for improving engine performance and fuel economy. In this thesis, we propose a new method to implement variable valve timing by positioning the angular position of camshaft. The camshaft then drives the valve to track designed trajectory. The method can eliminate the valve impact on its seating that occurs in electromagnetic engine valve. Moreover, it is able to reduce wear and acoustic noise.