Research For Digital Ignition System Of Motorcycle Engine

The digital ignition technology is brought forward to satisfy the stricter fuel consume and waste gas discharge standards of motorcycle, which owns benefits such as progressing well at the right moment, responding quickly and controlling ignition time precisely, compared with other ignition ways. It can effectively reduce fuel consumption and discharge of engine and improves the performance of engine by a large margin. Recently high-performance, multi-functional sensors and Large Scale Integrated circuits also promoted the application of this technology.A digital ignition system based on PIC single-chip for motorcycle is discussed in this paper. It flexibly adjusts ignition advance angle according to engine's working condition and keep engine working in the optimum condition to realize the digital control of ignition advance angle and improve the performance of engine .The digital ignition system makes most use of the original motorcycle magneto CDI system to lessen cost thus has high practical and economical value.The research work of this paper mainly includes two aspects:1. Design digital ignition system based on PIC single-chip for motorcycle The digital ignition system is supported by both hardware and software parts. The hardware part, using PIC single-chip as CPU, includes the realization of shaping circuits of rotation rate signals, throttle position circuit, ignition circuits and external communication circuits. The software part, programming by PIC language, includes capturing trigger signal model, scanning throttle position model, checking ignition MAP model, calculating model and time-lapse model. Meanwhile, a flow control model is developed creatively to improve the reliability of the digital ignition system. The digital ignition system is developed and tested by C120 magneto produced by Tianbo Keda Company. Results prove that the digital ignition system work stably and control ignition advance angle precisely.2. Testify the performance of engine using the digital ignition system through bed experimentThe bed experiment is carried out with CG125 engine in order to testify the utility and reliability of the digital ignition system. Compared with data obtained by original engine, the digital ignition system proves to improve the performance of engine and achieve the prospective goal.