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US 11,430,271 B2Granted
Fuel vapor treatment apparatus
AssigneeDenso Corporation
InventorRyoyu Kishi
Life of this patent
Estimating the term…
Abstract
A fuel vapor treatment apparatus is provided with a fuel tank for storing fuel of an internal combustion engine, a canister for adsorbing fuel vapor generated in the fuel tank, a pump for reducing a pressure inside a detection target system including the fuel tank, a pressure detection sensor for detecting the pressure inside the detection target system, and a fluctuation detection unit for detecting a fluctuation width of the pressure inside the detection target system at the time when the pressure inside the detection target system is reduced to a predetermined pressure value.
Claims15
A fuel vapor treatment apparatus comprising:
- a fuel tank for storing fuel of an internal combustion engine:
- a canister for adsorbing fuel vapor generated in the fuel tank;
- a pump for reducing a pressure in a detection target system including the fuel tank;
- a pressure detection sensor for detecting the pressure inside the detection target system;
- a fluctuation detection unit for detecting a fluctuation width indicating a width of a fluctuation of the pressure inside the detection target system, the fluctuation being generated when the pressure inside the detection target system is reduced to a predetermined pressure value;
- a leak diagnosis unit for diagnosing a leakage of gas between the inside and an outside of the direction target system based on a change amount per unit time of the detection value of the pressure detection sensor after reduction of the pressure inside the detection target system;
- and
- a reference correction unit for correcting a diagnosis reference, with which the detection value of the pressure inside the detection target system is compared to perform the leak diagnosis in the leak diagnosis unit, based on the fluctuation width of the pressure detected by the fluctuation detection unit.
5 more elements
A fuel vapor treatment apparatus comprising:
- a fuel tank for storing fuel of an internal combustion engine;
- a canister for absorbing fuel vapor generated in the fuel tank;
- a pump for reducing a pressure in a detection target system including the fuel tank;
- a pressure detection sensor for detecting the pressure inside the detection target system;
- a fluctuation detection unit for detecting a fluctuation width indicating a width of a fluctuation of the pressure inside the detection target system, the fluctuation being generated when the pressure inside the detection target system is reduced to a predetermined pressure value;
- and
- a leak diagnosis unit for diagnosing a leakage of gas between the inside and an outside of the detection target system based on a change amount per unit time of the detection value of the pressure detection sensor after reduction of the pressure inside the detection target system;
- wherein:
- the leak diagnosis unit diagnoses the leakage of gas between the inside and the outside of the detection target system by comparing the change amount per unit time of the detection value of the pressure detection sensor with a diagnosis reference which is set variably with the fluctuation width of the pressure, and
- the diagnosis reference is set to increase with an increase in the fluctuation width of the pressure.
7 more elements
A fuel vapor treatment apparatus comprising:
- a fuel tank for storing fuel of an internal combustion engine:
- a canister for adsorbing fuel vapor generated in the fuel tank;
- a fuel vapor passage connecting the fuel tank and the canister;
- a pressure detection sensor for detecting a pressure in the fuel tank;
- and
- a microcomputer configured to perform processing of:
- reducing the pressure in the fuel tank to a predetermined pressure value;
- closing the fuel vapor passage to form a closed system, which includes the fuel tank and a part of the vapor passage, as a detection target system;
- detecting a fluctuation width indicating a width of fluctuation of the pressure inside the detection target system after the pressure inside the detection target system is reduced to the predetermined pressure value;
- diagnosing a leakage of gas between the inside and an outside of the detection target system based on a change amount per unit time of the detection value of the pressure detection sensor after reduction of the pressure inside the detection target system;
- and
- correcting a diagnosis reference, which is used to perform the leak diagnosis, based on the fluctuation width of the pressure detected by the fluctuation detection unit.
9 more elements
A fuel vapor treatment apparatus comprising:
- a fuel tank for storing fuel of an internal combustion engine;
- a canister for absorbing fuel vapor generated in the fuel tank;
- a fuel vapor passage connecting the fuel tank and the canister;
- a pressure detection sensor for detecting a pressure in the fuel tank;
- and
- a microcomputer configured to perform processing of:
- reducing the pressure in the fuel tank to a predetermined pressure value;
- closing the fuel vapor passage to form a closed system, which includes the fuel tank and a part of the vapor passage, as a detection target system;
- detecting a fluctuation width indicating a width of fluctuation of the pressure inside the detection target system after the pressure inside the detection target system is reduced to the predetermined pressure value;
- diagnosing a leakage of gas between the inside and an outside of the detection target system based on a change amount per unit time of the detection value of the pressure detection sensor after reduction of the pressure inside the detection target system;
- diagnosing the leakage of gas between the inside and the outside of the detection target system by comparing the change amount per unit time of the detection value of the pressure detection sensor with a diagnosis reference which is set variably with the fluctuation width of the pressure;
- and
- setting the diagnosis reference to increase with an increase in the fluctuation width of the pressure.
10 more elements
Dependencies are inferred from the claim text.