Yanmar Co., Ltd.

Isao Takagawa

Takeshi Takahashi

Kazuhiro Yamada

Takashi Miyamoto

Hitoshi Adachi

Hideo Shiomi

Go Asai

Tomohiro Fukuda

Gou Asai

Hokuto Kusaka

An object is to provide an electronically controlled diesel engine capable of inhibiting the drastic increase of the fuel injection quantity from the fuel injection quantity before acceleration without the measurement of the relation between the number of revolutions of an engine, boost pressure, and the upper smoke limit of the fuel injection quantity. An electronically controlled diesel engine includes an judge part of an acceleration () that judges whether a control of acceleration is finished or not based on a difference between a target number of revolutions of the engine (Nset) and an actual number of revolutions of the engine (Ne). The electronically controlled diesel engine includes that the calculate part of a third upper limit of a fuel injection quantity () that is included in the calculate part of the upper limit of the fuel injection quantity () that sets an initial upper limit of a fuel injection quantity (Q) to a bigger injection quantity either of an injection quantity at the time of the judgment and a limit of a injection quantity based on the actual number of revolutions of the engine (Ne) at the time of the judgment when the judge part of an acceleration () determines that the condition of acceleration in the low speed area are satisfied and recover the limit value to the normal limit value until the judgment means of cancel of acceleration in the low speed area determines that the condition of cancel of acceleration in the low speed area are satisfied.

Electronically controlled diesel engine

Provided is an engine rpm control device which gradually reduces the output speed of an engine drive object when reducing the engine rpm. The engine rpm control device () includes a target engine rpm correction means used upon detection of an engine failure. The target engine rpm correction means has a storage device () containing a map of the correlation characteristic between the engine rpm and the output speed of object to be driven by an engine (). The target engine rpm correction means corrects the target engine rpm so that an instructed engine rpm (Nset) or a derating target engine rpm (Nset') is shifted to a predetermined failure-preventing engine rpm (N) while maintaining the reduction ratio of the output speed of the drive object at a predetermined ratio.

Engine RPM control device

In an electronic control governor that adjusts the amount of fuel supplied to an engine so as to coincide an engine rotation speed with a target rotation speed, by driving an actuator for actuating a fuel adjusting mean due to an actuator driving current overlapped with a dither current, an amplitude or frequency of the dither current is changed, corresponding to a change in the supply quantity of the actuator driving current. Or, the amplitude and frequency of the dither current are changed corresponding to a change in the engine rotation speed. Alternatively, a ratio between turn-on time and turn-off time during one period of the dither current is changed, depending on the velocity ratio between the increased velocity and the decreased velocity of the actuator driving current. Preferably, the ratio of the turn-on time to one period of the dither current is set at 20 to 40%.

Electronic control governor

A method for controlling an internal combustion engine, in which a traveling with reduced cylinders is controlled according to the idle-speed after the engine starting, so as to restrain the discharge of white smokes at the time lag for temperature equilibration soon after a cold starting. The method comprises a coolant water temperature detecting meansfor detecting the coolant water temperature in the internal combustion engine, a rotation speed detecting meansfor detecting the rotation speed of the internal combustion engineand a control means for controlling the operation of the internal combustion enginein accordance with the coolant water temperature and the rotation speed. When the internal combustion engine is evaluated that it is at the cold starting and the rotation speed reaches the predetermined rotation speed after the engine starting, a traveling with reduces cylinders is performed, which reduces the number of cylinders injecting fuels for a certain period of time.

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Osaka, Japan

Isao Takagawa