Rotary Valve Train A thesis submitted to the Faculty of the Mechanical Engineering Technology Program of the University of Cincinnati in partial fulfillment of the requirements for the degree of Bachelor of Science in Mechanical Engineering Technology at the College of Engineering & Applied Science by CLINTON C. LAFFERTY Bachelor of Science University of Cincinnati May 2011 Faculty Advisor: Dr. Ahmed Elgafy ABSTRACT This project was designed to fulfill the requirements of the Mechanical Engineering Department at the University of Cincinnati. The idea to redesign a cylinder head and valve train is not new however this design would aim to solve many of the common issues with current systems. By increasing the efficiency of the valve train while simplifying its design and keeping the majority of the system constant, this technology could be easily integrated into modern internal combustion engines. The end result would be an engine that is less expensive and quicker to manufacture, and produces more power while using less fuel. After conducting surveys of a wide breadth of potential consumers, from race engine builders to the everyday driver, compatibility with Variable Valve Timing was deemed most important. The design attempted to use the same geometry as a ball valve to control both the flow into and out of each cylinder, while also dictating the timing. This would combine the valves and camshaft into one part and also eliminate the valve springs. In order to maintain the stock timing a geometric relationship was calculated between the diameter of the valve openings and the overall diameter of the valve shaft. Again the design attempted to keep as many of the variables similar to the cylinder head and valve train they were modeled from. Ultimately a one quarter scale SLA rapid prototype model was created to demonstrate the design and provide a basis for some comparative testing. Both the original cylinder head and the scale model were tested on a flowbench in order to measure how efficiently they would allow air into and out of the cylinder. Although the area of passage for both the original and model were the same, the prototype flowed up to twenty five percent more air when increased to full scale using dimensional analysis. The design itself demonstrates a fulfillment of the remaining product objectives. The details of the process and development can be found in the following report. ii TABLE OF CONTENTS ABSTRACT .............................................................................................................................. II TABLE OF CONTENTS ........................................................................................................ III LIST OF FIGURES ................................................................................................................ IV LIST OF TABLES .................................................................................................................. IV INTRODUCTION .................................................................................................................... 1 BACKGROUND .................................................................................................................................................... 1 EXISTING METHODS ............................................................................................................ 2 DESIGN AND CONSTRUCTION OF A ROTARY INTAKE VALVE FOR A ONE CYLINDER INTERNAL COMBUSTION ENGINE ............................................................................................................................................................... 2 COATES INTERNATIONAL LTD. CSRV ROTARY CYLINDER HEAD ...................................................................... 3 EXISTING PATENTS ............................................................................................................................................. 4 SUMMARY .......................................................................................................................................................... 6 CUSTOMER FEEDBACK, FEATURES, AND OBJECTIVES ............................................. 6 SURVEY ANALYSIS ............................................................................................................................................. 6 ENGINEERING CHARACTERISTICS ....................................................................................................................... 8 PRODUCT FEATURES AND OBJECTIVES ............................................................................................................... 9 CONCEPT GENERATION AND SELECTION ................................................................... 11 SINGLE SHAFT DESIGN ..................................................................................................................................... 11 DUAL SHAFT DESIGN ....................................................................................................................................... 11 ROTARY ACTUATOR DESIGN ............................................................................................................................ 12 WEIGHTED DECISION MATRIX ......................................................................................................................... 12 CONCEPT SELECTION........................................................................................................................................ 13 COMPONENT DESIGN AND CALCULATIONS ............................................................... 14 FABRICATION AND ASSEMBLY ...................................................................................... 21 TESTING AND RESULTS .................................................................................................... 23 SCHEDULE AND BUDGET ................................................................................................. 26 CONCLUSION ....................................................................................................................... 27 REFERENCES ....................................................................................................................... 28 APPENDIX A - RESEARCH ................................................................................................... 1 APPENDIX B – CUSTOMER SURVEY AND RESULTS .................................................... 1 APPENDIX C – QUALITY FUNCTION DEPLOYMENT .................................................... 1 APPENDIX D – PRODUCT OBJECTIVES ............................................................................ 1 APPENDIX E – SCHEDULE .................................................................................................. 1 APPENDIX F – BUDGET ....................................................................................................... 1 APPENDIX G – DRAWINGS ................................................................................................. 1 iii LIST OF FIGURES Figure 1 - CSRV system with top half of head removed .......................................................... 3 Figure 2 - Valve Gear for Internal Combustion Engines .......................................................... 4 Figure 3 - Engine using a rotary valve system .......................................................................... 5 Figure 4 - Single Shaft Concept .............................................................................................. 12 Figure 5 - Dual Shaft Concept ................................................................................................ 13 Figure 6 - Rotary Actuator Concept........................................................................................ 14 Figure 7 - Toyota 4A-FE Timing Card ................................................................................... 15 Figure 8 - Intake shaft loading conditions .............................................................................. 17 Figure 9 - Intake Shaft Loading Conditions ........................................................................... 18 Figure 10 - Intake Shaft Shear and Moment Diagrams .......................................................... 18 Figure 11 - Exhaust Shaft Loading Conditions....................................................................... 19 Figure 12 - Exhaust Shaft Loading Conditions....................................................................... 19 Figure 13 - Exhaust Shaft Shear and Moment Diagrams ....................................................... 19 Figure 14 - Exploded View of Valve Train ............................................................................ 20 Figure 15 - Completely Assembled SLA Rapid Prototype of Rotary Valve Train ................ 21 Figure 16 - SLA Model with top half of cylinder head removed ........................................... 22 Figure 17 - SLA Model with top half of head and valve shafts removed ............................... 22 Figure 18 - Top of adapter plate showing gasket and locator pins ......................................... 23 Figure 19 - Bottom of adapter plate showing support legs ..................................................... 24 Figure 20 - Main orifice in flowbench where all adapters are placed .................................... 24 Figure 21 - Schedule of key project milestones ...................................................................... 26 LIST OF TABLES Table 1 - Average survey results .............................................................................................