Cooling device for internal combustion engine and failure diagnosis method for cooling device for internal combustion engine
US9695736B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 2014 |
| Grant date | Jul 4, 2017 |
| Priority date | — |
| Expiry date | Jun 25, 2035 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01P2031/00
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An ECU sets a leakage flow rate flowing through a radiator circulation passage in a closed state of a thermostat valve, calculates an estimated temperature of coolant water in the radiator circulation passage based on a set leakage flow rate and a detected water temperature of an engine-side coolant water temperature sensor, and performs a failure diagnosis for the thermostat valve based on a difference between the calculated estimated temperature and the detected water temperature of the radiator-side coolant water temperature sensor. The leakage flow rate during operation of the electric pump is set to be a larger value as compared to the leakage flow rate during stopping of the pump. As a result, a diagnostic can be prevented by improving an accuracy of failure detection for the thermostat valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.