System for controlling air flow to a vehicle air conditioning unit
US5623835A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1995 |
| Grant date | Apr 29, 1997 |
| Priority date | — |
| Expiry date | Aug 31, 2015 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B49/027
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An engine cooling fan control system includes a vehicle speed sensor, a pressure sensor for sensing the pressure of refrigerant provided to a refrigerant condenser forming part of the vehicle air conditioning system and a controller responsive to the vehicle speed and refrigerant pressure signals to operate an engine cooling fan. The engine cooling fan is activated continuously while vehicle speed is below a first speed threshold if the refrigerant pressure exceeds a first pressure. While the vehicle speed is above the first speed threshold, but below a second speed threshold, the engine cooling fan is activated for a predetermined duration if the refrigerant pressure is above the first pressure. Finally, while the vehicle speed is above the second speed threshold, the engine cooling fan is activated in response to the refrigerant pressure exceeding the first pressure and deactivated in response to the refrigerant pressure falling below a second lower pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.