Vehicular HVAC system with modified air recirculation for start-stop engine
US9657976B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 11, 2012 |
| Grant date | May 23, 2017 |
| Priority date | — |
| Expiry date | Oct 17, 2035 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B2700/2106
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A method and apparatus controls a recirculation position of a return vent in an HVAC system for a vehicle with a compressor driven by a start/stop engine. A partial recirculation position is set according to a basic recirculation strategy while the engine is operating. An auto stop event is entered at a time with the compressor operating. A full recirculation position is set during the stop event by an HVAC controller if a plurality of low fogging probability indicators are true. The low fogging probability indicators include a sensed ambient temperature being above a predetermined temperature, a sensed state of a windshield wiper being an off state, and a sensed sunload being above a predetermined sunload. The return vent is set at other than the full recirculation position by the HVAC controller according to the basic recirculation strategy if the low fogging probability indicators are not true.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.