Automobile Engine Flexible Flywheel Design And Manufacturing Technology And Research For Experimental

Automotive industry has been developed rapidly since the China’s Reform andOpening Up. Many car manufacturers gradually attach importance to the performanceand environmental friendly feature of the vehicle along with the increasing requirementof environmental friendly and energy saving since21stcentury. In order to meet theenvironmental friendly and energy saving requirement, many car manufacturers havepaid great attention to the design and development of vehicle transmission andpowertrain system, among which powertrain system accounts a big share. The core ofpowertrain system is engine which includes a very important component determiningthe start and operation of engine. That component is flywheel. Flywheel is acomparatively simple structured engine part, but of critical importance to the engine.This thesis focuses on the design and development of flexplate(a type offlywheel)which is mainly used on cars with automatic transmission. Flexplate is a partwith relatively big size and thin wall(typically2to3mm). This thesis mainly elaborateson the history of automotive engine flywheel, working principles, flexplate design,3Dmodeling, theoretical analysis, finite element stress analysis, sample parts build, sampleparts DV test, comparison between test data and theoretical data, mass production andmachining process etc.Features like flexplate appearance, tensile depth, balancing holes position etc. arestudied in design phase to determine a few flexplate complying with design requirement.PRO/E is used to set up the3D model. Then select the best design scenario by analyzingthe shape, structure and rotational inertia of these flexplate, and analyzing tresscondition by static and dynamic analysis with theoretical calculation and ANSYSworkbench. Production processes need be analyzed and compared for the selectedscenario. Then determine the optimal process: blanking, hole punching, shaping,reshaping, hole punching, balancing hole punching, de-burring, ring gear welding, etc.Dies cannot be built till mass production. Sample parts are prototype parts. Prototypeparts need to pass DV (design validation) and PV(production validation) tests beforemass production. The performance of flexplate directly affects that of vehicle. Thereforetest data needs to be collected after DV and PV tests and compared to the theoreticaldata. Data model needs to be set up to make the result clearer and easier to understand.Process will be designed after meeting all the requirements. Study stroke pattern of the die under minimum stress condition and find the best process. Process tests are carriedout thereafter and test result is consistent with the theoretical result. The mechanicalproperty of the flexplate meets the developing requirement of the company. Now thatflexplate has been in trial production.