Backflow prevention device and fan assembly
US9157536B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 24, 2011 |
| Grant date | Oct 13, 2015 |
| Priority date | — |
| Expiry date | Jan 2, 2034 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/3149
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A backflow prevention device includes at least one backflow prevention unit. The backflow prevention unit includes a frame, a first edge shutter plate, a second edge shutter plate and plural intermediate shutter plates. The frame includes an airflow channel. If the first inner sidewall is disposed over the second inner sidewall, the first edge shutter plate and the plural intermediate shutter plates are configured to open or close the airflow channel, and the slab of the second edge shutter plate is inactive. Whereas, if the second inner sidewall is disposed over the first inner sidewall, the second edge shutter plate and the plural intermediate shutter plates are configured to open or close the airflow channel, and the slab of the first edge shutter plate is inactive.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.