Electronically controlled hydraulic actuation type fuel injection device utilizing oil viscosity detection device and method

摘要

In an electronically controlled hydraulic actuation type fuel injection device, a viscosity value (mu) of hydraulic oil is detected by an oil viscosity detection sensor and then an aimed base valve opening time T.sub.injBASE during which a solenoid valve of a unit injector to be kept open is corrected based on the detected viscosity value. Lubricating oil for lubricating an engine is used as the hydraulic oil. The oil viscosity detection sensor includes an oil pump for supplying the lubricating oil to each sliding part of the engine and an oil sensor for detecting a delivery pressure Po of the oil pump. All of the sliding parts of the engine is regarded as one "throttle" and the viscosity (mu) of the hydraulic oil is determined according to a pre-prepared map from the engine speed Ne and the delivery pressure Po, utilizing change in passage resistance at the "throttle" caused by oil viscosity change. This oil viscosity detection device and the oil viscosity detection method utilizing that device can be easily added to every conventional engine as an option.