Isuzu Motors Limited

Yuji Sasaki

Futoshi Nakano

Koichiro Yomogida

Yusuke Saigo

The common rail fuel injection control device in accordance with the present invention computes a base duty (A) equivalent to a base target opening degree of a metering valve and a correction coefficient (B) based on the engine operation state, adds the value obtained by multiplying an oscillation duty (C) which oscillates periodically by the correction coefficient (B) to the base duty (A), and determines the final duty (D) equivalent to a final target opening degree of the metering valve.

Common rail fuel injection control device

The detected values of a common rail pressure that were detected by a pressure sensor are read within crank angle periods &#x394;t which are at least not more than half of a pumping cycle &#x394;T of a supply pump, the values detected within one pumping cycle preceding a reading time (for example, S(1), S(0), . . . S(&#x2212;4)) are averaged during each of the reading times, and the value thus obtained (for example, Pav()) is used as a common rail pressure after averaging processing, which is a representative value or a control value of the actual common rail pressure. The feedback control of common rail pressure is executed by using the values of common rail pressure after averaging processing thus computed by moving averaging. Consequently, the actual common rail pressure is converted into values suitable for control, and the feedback control of common rail pressure is executed with higher accuracy.

Filter processing device for detecting values of common rail pressure and common rail fuel injection control device

A fuel injection control device for executing multiple injection includes first means for determining the total injection quantity of fuel (Qtotal), second means for determining base injection quantities (QBsub) of each auxiliary injection, and third means which, when the sum (QBsubtotal) of base injection quantities (Qsub) of each of auxiliary injections is not larger than the value obtained by multiplying the total injection quantity (Qtotal) by a coefficient (K) (0<K&lE;1), computes the injection quantity (QTmain) of the main injection by subtracting the sum (QBsubtotal) from the total injection quantity (Qtotal), and when the sum (QBsubtotal) is larger than the value obtained by multiplying the total injection quantity (Qtotal) by the coefficient (K), computes the injection quantity (QTmain) of the main injection by reduction correcting the base injection quantities (QBsub) of auxiliary injections so that the sum (QBsubtotal&prime;) of injection quantities (QBsub&prime;) of auxiliary injections after the correction becomes not larger than the value obtained by multiplying the total injection quantity (Qtotal) by the coefficient (K), and by subtracting the sum (QBsubtotal&prime;) after the correction from the total injection quantity (Qtotal).

Fuel injection control device

A fuel injection quantity control device for controlling an actual revolution speed En of an engine to a target revolution speed Eo, comprises difference computation unit for subtracting the actual revolution speed En from the target revolution speed Eo and finding the difference e therebetween; proportional term computation unit for multiplying the aforesaid difference e by the prescribed proportionality constant Kp and finding a proportional term output value Qp; integral term computation means for finding an integral term output value Qi which is obtained by integrating the product of the aforesaid difference e and the prescribed integration constant Ki; differential term computation unit for finding a differential term output value Qd which is obtained by multiplying the value obtained by differentiating the aforesaid difference e by the prescribed differentiation constant Kd; and injection quantity computation unit for adding up the proportional term output value Qp and the integral term output value Qi and determining the injection quantity.

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Fujisawa, Japan

Yuji Sasaki