초록 ▼

This invention relates to a fuel feeding system for an internal combustion engine, which is suited for use in an in-cylinder injection internal combustion engine. In a system provided with a control valve so that a fuel pressure can be changed over for an adjustment, it is an object of the present i

This invention relates to a fuel feeding system for an internal combustion engine, which is suited for use in an in-cylinder injection internal combustion engine. In a system provided with a control valve so that a fuel pressure can be changed over for an adjustment, it is an object of the present invention to permit good combustion in the engine even when the control valve becomes inoperative. The system is composed of a fuel line (3) arranged between a fuel injection valve (1) and a fuel tank (2), a low-pressure fuel pump (4), a high-pressure fuel pump (5), a high pressure control unit (10) for controlling a pressure of fuel from the high-pressure fuel pump (5), a fuel pressure control valve (14) for opening or closing a bypass passage (13), which bypasses the high pressure control unit (10), in accordance with a state of operation of the internal combustion engine, a low pressure control unit (9) for controlling to a lower pressure than the high pressure control unit (10), a fault detection unit (31) for detecting a fault in the fuel pressure control valve (14) and a resulting restriction of an opening of the bypass passage (13), and a drive duration changing unit (32) for changing, upon detection of a fault, a drive duration of the fuel injection valve (1) in accordance with a predetermined fuel pressure higher than a pressure controlled by the low-pressure control unit (9).

대표청구항 ▼

[ I claim:] [1.] A fuel feeding system for an internal combustion engine, comprising:a low-pressure fuel pump (4) arranged between a fuel injection valve (1) disposed in said internal combustion engine and a fuel tank (2);a fuel line (3) constituted as a recirculating circuit which extends from said

[ I claim:] [1.] A fuel feeding system for an internal combustion engine, comprising:a low-pressure fuel pump (4) arranged between a fuel injection valve (1) disposed in said internal combustion engine and a fuel tank (2);a fuel line (3) constituted as a recirculating circuit which extends from said fuel tank (2) to said fuel injection valve (1) and further returns from said fuel injection valve (1) to said fuel tank (2);a high-pressure fuel pump (5) arranged in said fuel line (3) between said low-pressure fuel pump (4) and said fuel injection valve (1) and driven by said internal combustion engine;a high-pressure control unit (10) arranged in said fuel line on a downstream side of said high-pressure fuel pump (5) for controlling a pressure of fuel delivered from said high-pressure fuel pump (5);a fuel pressure control valve (14) arranged in a bypass passage (13), which extends from an upstream side to a downstream side of said high-pressure control unit (10), for opening or closing said bypass passage (13) in accordance with a state of operation of said internal combustion engine;a low-pressure control unit (9) for controlling, upon opening said bypass passage (13) by said fuel pressure control valve (14), a fuel pressure in said fuel line on an upstream side of said bypass passage (13) to a pressure lower than a pressure controlled by said high-pressure control unit (10);a fault detection unit (31) for detecting a fault in said fuel pressure control valve (14) and a resulting restriction of an opening of said bypass passage (13); anda drive duration changing unit (32) for changing, upon detection of a fault by said fault detection unit (31), a drive duration of said fuel injection valve (1) in accordance with a predetermined fuel pressure higher than a pressure controlled by said low-pressure control unit (9).