Toyota Jidosha Kabushiki Kaisha

Kabushiki Kaisha Toyota Jidoshokki

Tsutomu Kawae

Noriyuki Takada

Hisaki Ito

Hiroshi Kuzuyama

Shiro Tanno

Masahiro Machida

Takehito Hamamatsu

A compression-ignition internal combustion engine includes a fuel injection nozzle including a tip end portion exposed in a combustion chamber and a nozzle hole formed at the tip end portion; and a passage forming member forming a flow guide passage through which fuel injected from the nozzle hole passes. The passage forming member includes a passage wall portion located radially outward of the flow guide passage. The passage wall portion includes a first layer that is a base portion connected to a cylinder head, and a second layer located radially outward or radially inward of the first layer. The toughness of the first layer is higher than the toughness of the second layer. The thermal conductivity of the second layer is lower than the thermal conductivity of the first layer.

Compression-ignition internal combustion engine

A fuel injection valve has first injection holes, second injection holes, a first needle that opens and closes the first injection holes, and a second needle. The fuel injection valve is arranged such that a part of fuel injected from the first injection hole and a part of fuel injected from the second injection hole are gathered together at a position spaced from the side wall of the cavity by a predetermined distance. The second needle starts operating to open the second injection holes, after a predetermined time elapses from a point in time at which the first needle starts operating to open the first injection holes.

Internal combustion engine

An object of the present invention is to further improve the characteristic of the fuel spray of a fuel injection valve which has a plurality of stepped injection holes having a hole diameter of an outlet side injection hole larger than a hole diameter of an inlet side injection hole and which injects fuel from the stepped injection holes into a cylinder of an internal combustion engine. A cutout portion, which guides a flow of gas flowing into an outlet side injection hole from a lateral position of a fuel outlet of the outlet side injection hole during fuel injection, in a circumferential direction of the outlet side injection hole, is provided for at least one of both lateral portions between which the fuel outlet is interposed along with an arrangement direction of a plurality of injection holes, on a circumferential edge of the fuel outlet of the outlet side injection hole, in relation to at lease some of the injection holes of a fuel injection valve having the plurality of stepped injection holes.

Fuel injection valve

An object of the present invention is to improve the exhaust emission for a fuel injection valve having a stepped injection hole constructed so that a small diameter portion and a large diameter portion are communicated with each other with a stepped portion intervening therebetween. The present invention resides in a fuel injection valve comprising a cylindrical nozzle body which has a tip portion formed to have a conical shape, an injection hole which penetrates from an inner circumferential surface to an outer circumferential surface of the nozzle body, the injection hole being constructed so that a small diameter portion, which is positioned on a side of the inner circumferential surface of the nozzle body, is communicated with a large diameter portion which is positioned on a side of the outer circumferential surface of the nozzle body, with a stepped portion intervening therebetween, and a valve plug which is accommodated slidably in the nozzle body and which opens/closes the injection hole, wherein a ratio of the hole diameter of the large diameter portion with respect to the hole diameter of the small diameter portion is not less than 3.1 and not more than 4.0, a ratio of a length of the large diameter portion with respect to a length of the small diameter portion is not less than 0.25 and not more than 0.55, and a ratio of the length of the large diameter portion with respect to the hole diameter of the large diameter portion is not less than 0.4 and not more than 1.6.

A fuel injection device is provided with a fuel injection valve to inject fuel into a combustion chamber of an engine, and an electronic control unit to operate the fuel injection valve to inject the fuel in multiple separate injections. The electronic control unit controls a timing of a first fuel injection by the fuel injection valve to carry out the first fuel injection on the retard side with respect to a timing when a premix duration immediately after the first fuel injection is minimum, and controls a timing of a second fuel injection by the fuel injection valve in such a manner that a heat release rate waveform produced by the first fuel injection and the second fuel injection carried out thereafter has a double-peaked shape.

Growing community of inventors

Kariya, Japan

Tsutomu Kawae