Shut-off valve fault diagnosis device and fuel supply system
View Patent ↗Provided is a shut-off valve fault diagnosis device that performs fault diagnosis of a first shut-off valve that is disposed immediately after a gaseous fuel tank and a second shut-off valve that is disposed immediately before a regulator in a gaseous fuel supply system. The shut-off valve fault diagnosis device includes a diagnosis processing unit that performs a valve-shutting control of the first shut-off valve, performs a valve-shutting control of the second shut-off valve after a predetermined time has passed since the valve-shutting control of the first shut-off valve, and performs fault diagnosis of the first shut-off valve and the second shut-off valve based on a variation tendency in a fuel pressure between the first shut-off valve and the second shut-off valve after performing the valve-shutting control of the second shut-off valve.
1. A shut-off valve fault diagnosis device that performs fault diagnosis of a first shut-off valve that is disposed immediately after a gaseous fuel tank and a second shut-off valve that is disposed immediately before a regulator in a gaseous fuel supply system, the shut-off valve fault diagnosis device comprising:
a diagnosis processing unit that performs a valve-shutting control of the first shut-off valve, performs a valve-shutting control of the second shut-off valve after a predetermined time has passed since the valve-shutting control of the first shut-off valve, and performs fault diagnosis of the first shut-off valve and the second shut-off valve based on a variation tendency in a fuel pressure between the first shut-off valve and the second shut-off valve after performing the valve-shutting control of the second shut-off valve.
2. The shut-off valve fault diagnosis device according to claim 1 ,
wherein in a case where the variation tendency in the fuel pressure after performing the valve-shutting control of the second shut-off valve is in an upward tendency, the diagnosis processing unit determines that the first shut-off valve is in a fault state.
3. The shut-off valve fault diagnosis device according to claim 1 ,
wherein in a case where the variation tendency in the fuel pressure after performing the valve-shutting control of the second shut-off valve is in a downward tendency, the diagnosis processing unit determines that the second shut-off valve is in a fault state.
4. The shut-off valve fault diagnosis device according to claim 1 ,
wherein the diagnosis processing unit performs the fault diagnosis of the first shut-off valve and the second shut-off valve when an engine operation is stopped.
5. The shut-off valve fault diagnosis device according to claim 1 ,
wherein the diagnosis processing unit performs the fault diagnosis of the first shut-off valve and the second shut-off valve when gaseous fuel supply by the gaseous fuel supply system is switched to liquid fuel supply by a liquid fuel supply system.
6. A fuel supply system that is provided with a first shut-off valve that is disposed immediately after a gaseous fuel tank and a second shut-off valve that is disposed immediately before a regulator in a gaseous fuel supply system, the fuel supply system comprising:
a pressure sensor that detects a fuel pressure between the first shut-off valve and the second shut-off valve; and
a shut-off valve fault diagnosis device that performs a valve-shutting control of the first shut-off valve, performs a valve-shutting control of the second shut-off valve after a predetermined time has passed since the valve-shutting control of the first shut-off valve, and performs fault diagnosis of the first shut-off valve and the second shut-off valve based on a variation tendency in the fuel pressure after performing the valve-shutting control of the second shut-off valve.
7. The fuel supply system according to claim 6 ,
wherein in a case where the variation tendency in the fuel pressure after performing the valve-shutting control of the second shut-off valve is in an upward tendency, the shut-off valve fault diagnosis device determines that the first shut-off valve is in a fault state.
8. The fuel supply system according to claim 6 ,
wherein in a case where the variation tendency in the fuel pressure after performing the valve-shutting control of the second shut-off valve is in a downward tendency, the shut-off valve fault diagnosis device determines that the second shut-off valve is in a fault state.
9. The fuel supply system according to claim 6 ,
wherein the shut-off valve fault diagnosis device performs the fault diagnosis of the first shut-off valve and the second shut-off valve when an engine operation is stopped.
10. The fuel supply system according to claim 6 , further comprising:
a liquid fuel supply system in addition to the gaseous fuel supply system,
wherein the shut-off valve fault diagnosis device performs the fault diagnosis of the first shut-off valve and the second shut-off valve when gaseous fuel supply by the gaseous fuel supply system is switched to liquid fuel supply by the liquid fuel supply system.