| 摘要 |
PURPOSE:To aim at widening the flow regulating range of an injection valve by dividing a fuel pressure chamber into an ordinary fuel pressure chamber and an atmospheric air chamber. CONSTITUTION:Below a diaphragm 2 is provided a metallic bellows 5, and then, inward the bellows 5 is formed a fuel pressure chamber B, and outward the bellows 5 is formed an atmospheric air chamber C. The pressure receiving area S1 of the diaphragm 2 on the side facing a pressure chamber A and the pressure receiving area S2 thereof on the side facing the fuel pressure chamber B are varied from each other, where S1>S2. The pressure fluctuation in the pressure chamber A becomes a value S1/S2 times this amount in the fuel pressure chamber B, and varies at an inclination of S1/S2 in response to the pressure fluctuation in an intake pipe. Hereby, when an engine is in its light-load conditions where the intake pipe pressure is low, the injection differential pressure decreases so that injection at a lower rate of flow is obtainable. On the other hand, when an engine is in its heavy-load conditions where the intake pipe pressure is high, the injection differential pressure increases so that injection at a higher rate of flow is obtainable. |
