Abstract
Keywords:
Fuel injection, Turnover, Fuel cut valve, Fuel feed pump, FFP, In-line FI system, Two-wheeled vehicle
Abstract
Demanding of exhaust gas purification and further fuel economy improvement is increasing for small two-wheeled vehicles. Therefore, the adoption of fuel injection systems is increasing. The fuel injection system requires a fuel feed pump to supply fuel to the injector at high pressure. When a two-wheeled vehicle equipped with fuel injection system falls while the engine is operating, a rider cannot stop the engine immediately. Therefore a mechanism that can automatically stop the engine to prevent engine breakdown is necessary. The authors studied a valve mechanism which mechanically intercepts the fuel line upstream of the fuel injector. The structure equips a pendulum in the fuel passage, and the valve for fuel shutoff is attached in a housing that holds the pendulum. The housing is held at the vehicle side. The pendulum can be moved freely in the fuel within the housing. When a two-wheeled vehicle falls, a relative angle occurs into the pendulum and its vehicle, if the relative angle reaches the designated limit angle, the valve intercepts the fuel passage mechanically. This mechanism contributes to cost reduction. The engine stop performance when falling using the turnover fuel cut valve is more than the equal to the conventional electronic sensor. The purpose has been attained with a comparatively simple structure.