Mazda Motor Corporation

Hirofumi Yamauchi

Masanori Sahara

Shigeru Sakurai

Yoshitaka Nomoto

Tsutomu Matsuoka

Takumi Nishida

Kenji Ohkubo

Saburo Nakamura

Yosihtaka Nomoto

Kunihiro Yagi

Hideaki Kurita

A fuel injection system for a diesel engine is provided with a needle-lift-suppressing type fuel injection nozzle such as the central plunger type pintle fuel injection nozzle which has a valve needle adapted to be lifted under fuel pressure fed from a fuel injection pump to increase the effective spray area with increase in the lift of the valve needle and a needle-lift-suppressing means which limits the lift of the valve needle to a pre-lift of a predetermined amount at low load and/or low speed, and a starting detecting means for detecting starting of the engine, said needle-lift-suppressing means being arranged to permit lift of the valve needle beyond said pre-lift irrespective of the engine load and engine speed when the engine is started.

Fuel injection system for diesel engine

An internal combustion engine is provided in its exhaust system with a particulate filter for trapping combustible particulates contained in exhaust gas. A combustion promoting material injection device is provided for injecting a material for promoting combustion of the combustible particulates into the exhaust system upstream of the particulate filter. Further there are provided a bypass exhaust passage which bypasses the combustion promoting material injection device and the particulate filter, and a flow control valve which controls the amount of exhaust gas flowing through the bypass exhaust passage to control the amount of exhaust gas flowing into the particulate filter when said combustion promoting material is to be injected from the injecting device. When the combustion promoting material is injected, the flow control valve controls the amount of exhaust gas flowing into the particulate filter so that the combustion promoting material can uniformly adhere to the surface of the combustible particulates over the entire area thereof and so that the combustion temperature of the combustible particulates is prevented from rising abnormally high.

Exhaust gas cleaning system for vehicle

The fuel injection system for a diesel engine comprises a pintle type fuel injection nozzle having a valve needle slidable back and forth in the axial direction thereof between a first position in which its front end portion is inserted in a spray hole and a second position in which its front end portion is retracted from the spray hole, fuel supply means for feeding pressurized fuel to the fuel injection nozzle, and a plunger member which is slidable in the axial direction of the valve needle and provided with a front end face opposed to the rear end face of the valve needle and a rear end face adapted to receive the pressure of the pressurized fuel fed to the fuel injection nozzle from the fuel supply means, the valve needle being adapted to be lifted by a predetermined fuel pressure to a pre-lift position where the rear end face of the valve needle abuts against the front end face of the plunger member so that further lift of the valve needle is suppressed by the fuel pressure acting on the rear end face of the plunger member, thereby changing the valve opening pressure stepwise with change in the amount of lift of the valve. The injection system is provided with pre-lift change means for changing the amount of the pre-lift of the valve needle, an operating condition detecting means for detecting the operating condition of the engine, and a control means for controlling the pre-lift change means according to the output of the operating condition detecting means.

Growing community of inventors

Hiroshima, Japan

Hirofumi Yamauchi