ABNORMALITY SENSING DEVICE FOR EVAPORATION FUEL PURGE SYSTEM

• US 20160017849A1
• Filed: 07/07/2015
• Published: 01/21/2016
• Est. Priority Date: 07/15/2014
• Status: Active Grant

• Current Assignee: DENSO Corporation, Hamanako Denso Company Limited (DENSO Corporation)
• Original Assignee: DENSO Corporation, Hamanako Denso Company Limited (DENSO Corporation)
• Inventors: SHIRAI, Kosuke
• Granted Patent: US 10,294,895 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F02D 41/004 Control of the valve or purge actuator, e.g. duty cycle, closed loop control of position
• CPC Class Codes: F02M 25/0809 Judging failure of purge control system
• CPC Class Codes: F02M 25/0818 having means for pressurising the evaporative emission space
• CPC Class Codes: F02M 25/0836 Arrangement of valves controlling the admission of fuel vapour to an engine, e.g. valve being disposed between fuel tank or absorption canister and intake manifold
• CPC Class Codes: F02M 25/0854 Details of the absorption canister
• CPC Class Codes: F02M 25/089 Layout of the fuel vapour installation
• CPC Class Codes: F02M 35/10222 Exhaust gas recirculation [EGR]; Positive crankcase ventilation [PCV]; Additional air admission, lubricant or fuel vapour admission

Abstract

An abnormality sensing device for an evaporation fuel purge system is equipped with a purge passage that connects a canister to an intake passage of an internal combustion engine, a purge pump, a purge control valve, and a valve component that closes and opens the purge passage at a target passage including at least a first purge passage defined between the purge control valve and the intake passage. An abnormality determining portion detects a physical quantity relevant to a pressure change in the target passage in a determination possible state where the purge control valve allows the evaporation fuel to flow through the first purge passage and where the valve component prohibits the evaporation fuel from being supplied to the intake passage.

Claims

1. An abnormality sensing device for an evaporation fuel purge system comprising:

a fuel tank storing fuel;

a canister that adsorbs evaporation fuel generated in the fuel tank and that desorbs the evaporation fuel;

an intake passage of an internal combustion engine in which the evaporation fuel desorbed from the canister is mixed with fuel for combustion to be combusted;

a purge passage that connects the canister to the intake passage of the internal combustion engine;

a purge pump that pumps the evaporation fuel from the canister to the intake passage of the internal combustion engine;

a purge control valve disposed in the purge passage to control a flow of the evaporation fuel pumped by the purge pump to flow through the purge passage;

a valve component that closes and opens the purge passage to control the evaporation fuel to flow into the intake passage of the internal combustion engine at a target passage of the purge passage, the target passage including at least a first purge passage defined between the purge control valve and the intake passage of the internal combustion engine; and

an abnormality determining portion that determines whether there is an abnormality in the evaporation fuel purge system in a state where the evaporation fuel is pumped by the purge pump toward the intake passage of the internal combustion engine, wherein

the abnormality determining portion is in a determination possible state when the evaporation fuel is pumped toward the intake passage of the internal combustion engine by the purge pump, when the purge control valve allows the evaporation fuel to flow through the first purge passage, and when the valve component prohibits the evaporation fuel from being supplied to the intake passage of the internal combustion engine, and

the abnormality determining portion detects a predetermined physical quantity relevant to a pressure change in the target passage in the determination possible state, and determines whether there is an abnormality in the evaporation fuel purge system according to the predetermined physical quantity.

2. The abnormality sensing device according to claim 1, wherein

the valve component is disposed in a duct component that defines the intake passage of the internal combustion engine and that does not define the target passage.

3. The abnormality sensing device according to claim 1, wherein

the predetermined physical quantity is a pressure detected in the first purge passage.

4. The abnormality sensing device according to claim 1, wherein

the predetermined physical quantity is a consumption current or consumption voltage of the purge pump.

5. The abnormality sensing device according to claim 1, wherein

when the abnormality determining portion determines that the evaporation fuel purge system is abnormal in the determination possible state, as a first passage prohibition state, the purge pump pumps the evaporation fuel toward the intake passage of the internal combustion engine, and the purge control valve controls the evaporation fuel not to flow through the first purge passage,

in the first passage prohibition state, the abnormality determining portion detects a pressure change in a second purge passage that connects the purge pump to the purge control valve, and determines whether there is an abnormality in the second purge passage according to the pressure change, and

the abnormality determining portion determines that an abnormality is generated in the first purge passage when it is determined that there is no abnormality in the second purge passage.

6. The abnormality sensing device according to claim 1, wherein

when the abnormality determining portion determines that the evaporation fuel purge system is abnormal in the determination possible state, as a first passage confined state, the purge control valve is closed to confine the evaporation fuel in the first purge passage,

in the first passage confined state, the abnormality determining portion detects a pressure change in the first purge passage, and determines whether there is an abnormality in the first purge passage according to the pressure change, and

the abnormality determining portion determines that an abnormality is generated in a second purge passage that connects the purge pump to the purge control valve when it is determined that there is no abnormality in the first purge passage.

7. The abnormality sensing device according to claim 1, wherein

the purge control valve has a valve object that is configured to operate to close the purge passage when the first purge passage adjacent to the valve component has a negative pressure by operation of the internal combustion engine.