Nippondenso Co., Ltd.

Yasuhiro Kariya

Takashi Iwanaga

Kenji Funai

Mitsuru Ban

Kenji Magario

Takayoshi Kawaguchi

Nobuhiko Shima

In a system in which a common rail accumulates fuel pressurized by a high pressure supply pump, when a pipe connected to the common rail is damaged or a pulsation of fuel injection is caused in the system, reliability of the system is greatly affected because of high pressure. According to the present invention, a mechanism to prevent leakage of fuel from the common rail even when the pipe is damaged, or a mechanism to damp a pulsation of fuel pressure, is provided in a pipe close to the common rail. Therefore, reliability of the system is improved.

Accumulator type of fuel injection device

A safety valve provided in a fuel injection apparatus includes an accumulator in which fuel is accumulated. The housing has an inside passage for introducing high-pressure fuel of the accumulator into the inside of the housing and a seat face formed at a portion of the inside passage. A valve element provided movably within the housing includes a valve body to open/close the seat face and an elastic member for pressing and biasing the valve element in a closing direction. A fuel chamber defined between the inner surface of the housing and the valve element maintains pressure for pressing the valve element in a valve-opening direction, and high pressure fuel from the inside passage is introduced into the fuel chamber when the valve body of the valve element is separated from the seat face. With this safety valve, the high-pressure fuel of the accumulator is introduced into the fuel chamber in order to press the valve element in the valve-opening direction so that the valve element will be rapidly opened, with the result that the fuel pressure in the accumulator can recover a predetermined value instantaneously.

Safety valve for fuel injection apparatus

Growing community of inventors

Hino, Japan

Yasuhiro Kariya