Constant air flow control apparatus and method
US5447414A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 1994 |
| Grant date | Sep 5, 1995 |
| Priority date | — |
| Expiry date | May 27, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/929
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Air handling apparatus (10) for delivering a volume of air at a generally constant flow rate regardless of changes in the operating conditions of a system with which the apparatus is used. A blower (12) pushes air from one point to another. The blower is operated by a blower motor (14). A switch (16) controls application of power to the motor. Sensors (20) are used to sense the voltage supplied to the motor, the current drawn by the motor, and the motor's operating speed. A flow controller (22) establishes a desired air flow rate to be provided by the blower. A processor (18) is responsive to the sensed voltage (V), current (I), and speed (S), an input (C) from the flow controller, and constants (K1-K4) related to performance characteristics of the blower to determine a torque required by the motor to produce a predetermined air flow rate. The torque value is determined as a function of the combined motor speed input from the sensor and an input from the flow controller. The processor is responsive to a calculated torque value for the motor. The processor supplies a control signal to the switch to control application of a voltage to the motor. This voltage is sufficient for the mot…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.