Ventilation device
US8669730B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 2010 |
| Grant date | Mar 11, 2014 |
| Priority date | — |
| Expiry date | Sep 10, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B30/70
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A ventilating system that can make an air flow rate variable includes a DC motor that drives blades and a control circuit that controls the DC motor. The control circuit includes a first current detecting unit that detects a current flowing in the DC motor, a rotating speed detecting unit that detects a rotating speed of the DC motor, and a control unit that controls the DC motor based on a rotating speed detected by the rotating speed detecting unit and a current detected by the first current detecting unit. The current detecting unit includes a plurality of low-resistance resistors, detects a motor current by using divided voltages of the low-resistance resistors, and calculates a ventilation air flow rate based on the rotating speed detected by the rotating speed detecting unit and the current detected by the first current detecting unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.