Abstract: Based on patent analysis into 3 kinds of diesel engine fuel injection system (electronically controlled unit pump system, electric control unit injector system, common rail fuel injection system), the competitive situation of these systems were investigated from 5 aspects, including patent application trend, technology development trend, regional distribution, rival agencies and applications in agricultural machinery engine. It was shown that the development of electronically controlled unit pump system and electric control unit injector system tended to be stable, with new technical inventions laying out in system components and new materials. Common rail fuel injection system related technologies were going to be mature. Germany and Japan hold absolutely leading positions in this field, while the research and development of China in this field was still in its infancy.

Key words: agricultural machinery, fuel injection system, unit pump system, unit injector system, common rail, patent analysis