Internal combustion engine system
AssigneeToyota Jidosha Kabushiki Kaisha
InventorHiromichi YASUDA
Life of this patent
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Abstract
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.
Claims12
An internal combustion engine system, comprising:
- an in-cylinder pressure sensor that includes:
- a housing that is formed into a cylindrical shape;
- a pressure receiving member that is provided at one end of the housing and configured to receive an in-cylinder pressure, the in-cylinder pressure being a pressure of a gas inside a combustion chamber;
- and a pressure detecting element that is arranged inside the housing and into which a compressive load that is based on the in-cylinder pressure configured to be input from the pressure receiving member, the pressure detecting element being configured to emit an output in accordance with the input compressive load;
- a crank angle sensor configured to detect a crank angle;
- a seal portion configured to, at a position that is further on the combustion chamber side than the pressure detecting element in an axial direction of the housing, seal a space between an outer face of the housing and a wall surface of the combustion chamber that surrounds the housing;
- and
- a controller, the controller programmed to:
- calculate a heat release amount in a cylinder that is an amount of heat released by combustion, based on in-cylinder pressure data that is data regarding an in-cylinder pressure that is detected by the in-cylinder pressure sensor;
- calculate a first ratio that is a ratio of an amount of decrease in a heat release amount relative to an amount of increase in a crank angle in a period during an expansion stroke from an crank angle at which a calculated heat release amount exhibits a maximum value until an opening timing of an exhaust valve;
- and
- determine existence or nonexistence of an abnormality in a sealing function of the seal portion based on the first ratio and an engine speed.
Dependencies are inferred from the claim text.