Komatsu Corporation

Takashi Sakasai

Daisuke Yoshida

Tadashi Iijima

Shuki Akushichi

Jiro Akagi

Hideo Furukawa

Shouhei Nagasaka

Hiroshi Ohta

Hiroyasu Sato

Kouichi Okaya

Norifumi Abe

Mitsuru Nakashima

Kinichirou Watanabe

Takanobu Akutsu

Kaoru Sakurai

Tooru Okazaki

A diesel engine, includes: an exhaust gas recirculation device that recirculates an exhaust gas emitted from the diesel engine to an intake side of the diesel engine; an intake air amount sensor that measures an intake air amount of the diesel engine; a NOx measurement sensor that measures NOx contained in the exhaust gas emitted from the diesel engine; and a control device that obtains a correction value for correcting a measured value by the intake air amount sensor based on a difference between first information on NOx obtained based on information on a rotation speed of the diesel engine and information on a load and second information on NOx measured by the NOx measurement sensor to control the exhaust gas recirculation device based on the measured value by the intake air amount sensor corrected using the correction value.

Diesel engine and method for controlling diesel engine

A diesel engine capable of favorably preventing the generation of white smoke even when an engine load is shifted from a high load side to a low load side. For this purpose, a diesel engine () includes fuel injection timing control means () for controlling fuel injection timing, the fuel injection timing control means () advances the fuel injection timing by predetermined time when an engine load becomes a predetermined load (Ff) or lower in an engine stopping step of stopping the diesel engine while gradually reducing the engine load.

Diesel engine

In a fuel injection apparatus , a fuel injection rate from which is controlled by a fuel pressure, a branch pipe comprising a tubular member with the tip end closed is provided between a second pressure control valve and a second pressure sensor . The branch pipe extends in a direction along a flow direction of the fuel just before the branch pipe , and has a capacity not less than one fifth of that of a fuel flow path between the second pressure control valve and a fuel chamber . When a pressure difference in the pressure control valve becomes larger and vibration of the fuel pressure is generated, the branch pipe absorbs and reduces the vibration. As the vibration of the fuel pressure is reduced, a stable fuel injection rate is realized.

Fuel injection apparatus

A diesel engine ( ) has: a flow adjuster ( ) for throttling exhaust flow; an intake heater ( ) for heating intake air; a thermal medium circulator ( ) for circulating a thermal medium to warm the diesel engine ( ); a cylinder cut-off device ( ) for conducting cylinder cut-off; and a fuel injection timing advancing device ( ) for advancing timing for supplying fuel to a cylinder, the respective devices being actuated at least from pre-high-idle step to a neighborhood of high-idle condition, so that fuel combustion stabilization of the diesel engine ( ) can be rapidly enhanced during a period where less fuel is supplied into the cylinder and fuel combustion time is short, thus greatly reducing discharge of white smoke and possibility of engine bunching.

The invention provides a voltage control apparatus of an engine generator having a simple structure and capable of being made compact, and a control method thereof. Accordingly, in a method of controlling a voltage of an engine generator, the method includes steps of detecting an actually measured value (Ne) of an engine rotational speed at every predetermined time and controlling an output voltage of the power generator ( ) in accordance with a deviation value (&agr;1) between a predetermined target value (Ne1) and the actually measured value when the actually measured value is equal to or less than the target value. Further, the method includes the steps of detecting an actually measured value (Q) of a fuel injection amount of an engine ( ) and an actually measured value (Ne) of a rotational speed at every predetermined time and controlling an output voltage of the power generator in accordance with a deviation value (&agr;2) between a predetermined target value (Q1) of the fuel injection amount with respect to the actually measured value of the rotational speed and the actually measured value of the fuel injection amount. Further, the method can be made such as to detect the actually measured value of the engine rotational speed at every predetermined time and control the output voltage of the power generator on the basis of the time change rate of the actually measured value.

Voltage control apparatus of engine generator and control method thereof

An inductive load driving device in which the rise of load current at an initial stage of driving can be executed at high speed includes a plurality of step-up circuits (,), for alternately applying a high voltage to the same inductive load within a predetermined period of time, to thereby allow each load current to rise at a high speed; a holding current output circuit (,), for applying a predetermined voltage to the same inductive load after the load current has risen, to thereby hold the load current at a predetermined value; a plurality of switching means (,), adapted to be switched in such a manner that the respective outputs of the plurality of step-up circuits (,) and the holding current output circuit (,) can be alternately connected to the same inductive load; and a control logic circuit (,), for switching the plurality of switching means (,) in a predetermined sequence.

Inductive load driving device and driving method

The present invention is a control device and a control method for a cam driving type electronic control unit injector, in which driving force transmitting parts do not separate from a cam even when a high injection pressure is used. For this purpose, the control device includes a feed and pressure passage (,) for providing communication between an oil reservoir (,) and a plunger chamber (,), a valve (,) for opening and closing the feed and pressure passage (,), a first solenoid (,) for moving the valve (,) during an injection stroke to close the feed and pressure passage (,) to raise a pressure in the plunger chamber (,), a spring (,) for pressing the valve (,) to open the feed and pressure passage (,), and a control means (,) for supplying a smaller current than that when the valve (,) is moving during the aforesaid injection stroke, through the first solenoid (,) for a predetermined period (AV,) after the lapse of a predetermined period of time (T,) immediately after completion of main injection to move the valve (,) in a closing direction of the feed and pressure passage (,) to thereby output a command for raising the pressure in the plunger chamber (,).

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Oyama, Japan

Takashi Sakasai