US 10,378,461 B2 · Engine device

Abstract

An engine device (21) including: an intake manifold (67) configured to supply air into a cylinder (77), an exhaust manifold (44) configured to output exhaust gas from the cylinder; a gas injector (98) which mixes a gaseous fuel with the air supplied from the intake manifold; and a main fuel injection valve (79) configured to inject a liquid fuel into the cylinder for combustion. At the time of switching the operation mode from one to another between a gas mode and a diesel mode, a supply amount of a first fuel to be supplied in a post-switching operation mode is increased to a switching threshold value through an increase control which monotonously increases the supply amount, and then is controlled by a speed-governing control based on the engine rotation number. The switching threshold value is set based on the engine rotation number or the engine load.

Claims20

Dependent claims

An engine device comprising:

an intake manifold configured to supply air into a cylinder;
an exhaust manifold configured to output an exhaust gas from the cylinder;
a gas injector configured to mix a gaseous fuel with the air supplied from the intake manifold;
and
a main fuel injection valve configured to inject a liquid fuel into the cylinder for combustion, the gas injector and the main fuel injection valve being coupled to the cylinder, and
an engine controlling device configured to switch operation modes between:
a gas mode in which the gaseous fuel is supplied into the cylinder;
and
a diesel mode in which the liquid fuel is supplied into the cylinder,
wherein, to switch between the operation modes, the engine controlling device is configured to:
calculate a switching threshold value based on an engine rotation number;
and
based on a determination that a first fuel supply amount of a first fuel is greater than or equal to the switching threshold value, perform a speed-governing control of the first fuel supply amount.

10 more elements

An engine system comprising:

an engine controlling device configured to drive an engine in either:
a gas mode in which gaseous fuel is supplied into a cylinder of the engine;
or
a diesel mode in which liquid fuel is supplied into the cylinder,
wherein:
prior to a time of switching an operation mode from one to another between the gas mode and the diesel mode:
a supply amount of a second fuel to be supplied in a pre-switching operation mode is controlled by a speed-governing control based on an engine rotation number;
at the time of switching an operation mode from one to another between the gas mode and the diesel mode:
a supply amount of a first fuel to be supplied in a post-switching operation mode is increased to a switching threshold value through an increase control which monotonously increases the supply amount, the switching threshold value is set based on an engine rotation number or an engine load;
and
after the supply amount of the first fuel reaches the switching threshold value through the increase control:
the first fuel to be supplied in the post-switching operation mode is controlled by the speed-governing control based on the engine rotation number;
and
the supply amount of the second fuel is decreased by a decrease control which monotonously decreases the supply amount.

11 more elements

Dependencies are inferred from the claim text.

Engine device

Life of this patent

Engine device

Life of this patent

Abstract

Claims20