The object of the invention is to obtain a thermal flowmeter which effectively causes water droplets to be directed to a discharge port when the water droplets adhered to a wall surface of a first passage are drawn into a third passage portion. A thermal flowmeter of the present invention includes a sub-passage that takes a measurement gas flowing through a main passage; and a flow detection unit that measures a flow rate of the measurement gas by performing heat transfer with the measurement gas flowing through a sub-passage. Further, the sub-passage includes a first passage, a second passage portion branching in the middle of the first passage portion to be directed toward the flow detection unit; and a third passage portion branching in the middle of the second passage portion to be directed toward a third outlet, and a pressure loss generation means is provided between a third inlet and the third outlet of the third passage portion.

A system and method for controlling operation of an internal combustion engine having at least one fuel injector. A controller is configured to selectively command the at least one fuel injector to deliver a primary fuel injection of a first fuel quantity and a secondary fuel injection of a second fuel quantity. The first fuel quantity is above a predefined threshold and the second fuel quantity is at or below the predefined threshold. The controller is configured to command a primary pulse width and a secondary pulse width, based in part on a respective desired fuel injection mass and respective initialized values of fuel injector slope. Operation of the fuel injectors is controlled based in part on a converged primary fuel injector slope and a converged secondary fuel injector slope determined at partially from a comparison of a calculated fuel mass and an estimated fuel mass.

A method of controlling a high pressure gas injection internal combustion engine includes injecting, in a first combustion mode, by a first as injection system, a first gaseous fuel into a cylinder of the engine, and accumulating in a container of a second gas injection system excess gaseous fuel from the first fuel system, shifting, in the cylinder, from the first combustion mode to a second combustion mode including determining a value of an air flow related parameter indicative of an air mass flow into the cylinder, determining, based on the determined air flow related parameter value, a value of a fuel flow related parameter indicative of a mass flow of the excess gaseous fuel, and supplying from the container, in accordance with the determined fuel flow related parameter value, the excess gaseous fuel to provide a premix of air and the excess gaseous fuel to the cylinder.

A flow rate detector includes a detection circuit, which is configured to output as an analog signal a voltage in accordance with a flow rate of air flowing through an intake pipe, and a conversion circuit, which is configured to convert the analog signal input from the detection circuit to a digital signal based on an analog-to-digital conversion characteristic to output the digital signal. The analog signal that corresponds to a forward flow direction and is input to the conversion circuit is set to have a value larger than an input voltage range in which a missing code may occur in the analog-to-digital conversion characteristic.

A method for operating an internal combustion engine having at least two cylinders and having a single injector for central point injection of fuel into an air intake connected to the cylinders, wherein for each of the cylinders an injection quantity of the fuel and a starting time of the injection are specified and set as a function of the present engine load and the present engine speed. The invention further relates to such an internal combustion engine.

Control of fuel flow in a uniflow-scavenged, two-stroke cycle, opposed-piston engine includes limiting an amount of torque or fuel in response to a torque demand, based upon a comparison and a selection of fuel delivery options derived from a global airflow parameter and/or a trapped airflow parameter.

A multi-injection process includes performing intake synchronized injection in which fuel is injected in synchronism with an open valve period of an intake valve, and an intake asynchronous injection in which fuel is injected at a more advanced timing than during intake synchronized injection. A single-injection process includes injecting a required injection amount of fuel by intake asynchronous injection. An operating process includes operating a port injection valve for injecting fuel into an intake passageway. A selection process includes selecting the single-injection process if the temperature of an intake system of an internal combustion engine is not lower than a prescribed temperature, and selecting the multi-injection process if the temperature of the intake system is less than the prescribed temperature.

An injector injection amount control device includes: acquiring a measured value of a crank angle that is a rotation angle of a crankshaft of an engine, determining instruction injection amounts of fuel from respective injectors, the respective injectors corresponding to a plurality of cylinders of the engine, estimating a torque arising in each of the plurality of cylinders of the engine based on a non-linear Kalman filter employing an error between the acquired measured value of the crank angle and an estimate value of the crank angle, and correcting the instruction injection amounts for the respective injectors corresponding to the plurality of cylinders such that each of the plurality of estimated torques falls within the same range.

A method for controlling the air-fuel ratio of a vehicle includes: calculating the air amount charged in a cylinder of an engine by using a fresh air amount, a residual air amount remaining inside the cylinder of the engine, and a backflow gas amount flowing back into the cylinder upon the valve overlap of an intake vale and an exhaust valve of the engine, correcting it with the purge gas flow rate supplied to an intake manifold of the engine when the active purge system is operated, calculating the final fuel amount by correcting the fuel amount injected by a fuel injection device with the amount of the fuel component contained in the purge gas when the active purge system is operated, and controlling the air-fuel ratio based on the final air amount and the final fuel amount.

Provided is a device for controlling a fuel injection device capable of suppressing deterioration of exhaust performance while ensuring driving performance when acceleration of a vehicle is requested during an intake stroke. Therefore, when the acceleration of a vehicle is requested during an intake stroke in one combustion cycle, an engine control unit 9 estimates an increase (acceleration intake air amount Qad) of the amount of air taken in a combustion chamber 19 of an internal combustion engine 1 associated with the acceleration of the vehicle after the acceleration of the vehicle is requested in one combustion cycle based on a lift amount of an intake valve 3. The engine control unit 9 controls a fuel injection valve 5 so as to increase a fuel injection amount in one combustion cycle according to the acceleration intake air amount Qad.