An engine torque estimator for an internal combustion engine, includes a cylinder internal pressure sensor, an indicated-torque calculator, a pump loss torque calculator, and an engine torque calculator. The cylinder internal pressure sensor detects a cylinder internal pressure in a cylinder. The indicated-torque calculator calculates an indicated torque in a second combustion cycle based on the cylinder internal pressure detected in a period from an exhaust stroke in a first combustion cycle to an expansion stroke in the second combustion cycle. The second combustion cycle that follows the first combustion cycle. The pump loss torque calculator calculates a pump loss torque in the second combustion cycle based on the cylinder internal pressure detected in the period. The engine torque calculator calculates an engine torque of the internal combustion based on the indicated torque and the pump loss torque.

A pressure sensor includes: a diaphragm joined to a front side of a housing via a joint portion; a sensor portion; a connection portion connecting the diaphragm to the sensor portion; and a heat receiving portion disposed at the front side of the diaphragm. When: a minimum value of an area of a minimum inclusion region which is a virtual region, which include a cross-section of a portion from the heat receiving portion to the diaphragm and of which an overall length of a contour become minimum on a cross-section perpendicular to the axial line, is defined as a connection area Sn; and an area of a region surrounded by the joint portion on a projection plane perpendicular to the axial line when the diaphragm and the heat receiving portion are projected onto the projection plane is defined as a diaphragm effective area Sd, (Sn/Sd)0.25 is satisfied.

An ignition system for an engine is disclosed. The ignition system may have an igniter connected to selectively ignite a fuel mixture within the engine, at least one sensor configured to sense operation information of the engine and generate corresponding signals, and a controller in communication with the igniter and the at least one sensor. The controller may be configured to cause a first striking of the igniter to ignite the fuel mixture, make a determination that the fuel mixture has been ignited by the igniter based on the signals, and selectively cease striking of the igniter based on the determination.

A cylinder head includes: a cylinder head body; multiple fuel ports extending to cylinders from a sidewall surface of the cylinder head body, the sidewall surface being located on one side of a longitudinal axis, on which intake ports are disposed; multiple injection valve attachment bosses projecting from the sidewall surface, surrounding openings of the fuel ports, and adapted to attach cylinder fuel injection valves to the fuel ports; and multiple projections projecting from the sidewall surface and disposed adjacent to the corresponding injection valve attachment bosses. A cylinder block includes: a cylinder block body; and a sensor attachment boss projecting from a sidewall surface of the cylinder block body, the sidewall surface being located on the one side of the longitudinal axis, on which the sidewall surface of the cylinder head body is located. The sensor attachment boss is adapted to attach a knock sensor to the cylinder block.

An engine assembly for a vehicle and method for determining piston component temperature. The assembly includes an engine defining at least one cylinder, the engine including at least one piston disposed in the at least one cylinder, the at least one piston and the at least one cylinder together defining at least in part at least one variable volume combustion chamber; and at least one temperature sensor connected to the engine, the at least one temperature sensor being arranged to measure a temperature of fluid within the at least one combustion chamber.

Methods are provided for reliably self-testing a water injection system that injects water into the engine responsive to engine operating conditions such as knock, the water injection system refilled manually or via the collection of water on-board the vehicle. Responsive to a water injection error, learned based on a change in a defined set of engine parameters while ramping water injection during selected conditions, the presence of clogging in a water line may be determined. Based on a degree of clogging, subsequent water injection may be appropriately adjusted.

PROBLEMS TO BE SOLVED To provide an in-cylinder flow measuring method and a system thereof in an internal combustion engine configured to grasp simultaneously an air-fuel mixture flow and the flame behavior in the flow field under the firing condition.

MEANS FOR SOLVING PROBLEMS The in-cylinder flow measuring system comprises an engine 10 having an optically-visible cylinder from at least one direction selected from three directions comprising a direction from a cylinder linear, a direction from a pent-roof, and a direction from a piston top such that a flow occurring inside the cylinder can be measured, a solid tracer particle supplier 2A configured to supply a solid tracer particle into the cylinder of the engine during an intake stroke, a liquid tracer particle supplier 2B configured to supply a liquid tracer particle into the cylinder of the engine during the intake stroke, a laser irradiation apparatus 3 comprising a light source 30 for irradiating a laser light and configured to form a laser sheet inside the cylinder by the laser light irradiated from the light source 30, an imaging apparatus 4 configured to capture an image of the inside of the cylinder in which the laser sheet is formed by the laser irradiation apparatus 3, a controller 6 configured to synchronize an oscillation period for the laser irradiation apparatus 3 to irradiate the laser light with a frame rate for the imaging apparatus 4 to capture the image, and an analyzer 5 configured to analyze the image captured by the imaging apparatus 4.

An internal combustion engine system includes: an in-cylinder pressure sensor; a crank angle sensor; and a seal portion that seals a space between an outer face of a housing and a wall surface of a cylinder head. A slope that is a ratio of the amount of decrease in a heat release amount relative to the amount of increase in a crank angle is calculated in a period during an expansion stroke from a combustion end point until an opening timing of an exhaust valve. The existence or nonexistence of an abnormality in the sealing function of the seal portion is determined based on whether or not a ratio of the amount of decrease in the slope to the amount of increase in an engine speed is greater than a threshold value.

A method of monitoring an operating event of a combustion engine includes receiving a noise signal sensed by a knock sensor disposed in or proximate to the combustion engine, correlating the noise signal with a fingerprint having at least an ADSR envelope indicative of the operating event, and detecting if the operating event has occurred based on the correlating of the noise signal with the fingerprint.

An enforced one-time snap connection system mounts a first component to a second component. The first component has a circumferentially extending groove formed into an exterior surface. The second component has an annular mounting adapter having an internal bore. An annular retainer is secured on an end of the second component at the internal bore, the annular retainer includes an axially extending annular portion having a radially inwardly projecting annular locking rib received into the circumferentially extending groove during installation of the first component into the second component such that the annular locking rib or locking tabs and/or the circumferentially extending groove are critically damaged or destroyed if the first component is removed from the second component, thereby preventing re-assembly and re-locking of the components together again.