Automatic temperature and humidity regulation – Ventilator type – Electrically actuated
Reexamination Certificate
2006-01-13
2010-06-01
Jiang, Chen-Wen (Department: 3744)
Automatic temperature and humidity regulation
Ventilator type
Electrically actuated
C700S276000, C700S277000, C700S300000
Reexamination Certificate
active
07726582
ABSTRACT:
A control strategy for supply fans in constant-volume heating, ventilating, and air-conditioning (HVAC) systems that reduces the speed of the fan at part-load conditions is provided. The invention consists of a constant-volume HVAC system, wireless discharge air temperature sensors, wireless hot source and cold source temperature sensors, and a wireless controller coupled to a fan modulation device. The controller includes a finite state machine that switches between a high-temperature control mode and a low-temperature control mode. The controller also includes a calculator that calculates a high temperature setpoint and a low temperature setpoint as a function of the hot source and cold source temperatures. In high temperature control mode, the controller compares the maximum discharge air temperature with the high temperature setpoint, and it commands the fan modulating device so that the maximum discharge air temperature remains close to the high temperature setpoint. In low temperature control mode, the controller compares the minimum discharge air temperature with the low temperature setpoint, and it commands the fan modulating device so that the minimum discharge air temperature remains close to the low temperature setpoint. Alternatively, the controller includes a calculator that computes a largest load as a function of previous fan command, discharge air temperatures, and readings from wireless zone temperature sensors. The controller increases the speed of the fan as the largest load increases, and reduces the speed of the fan as the largest load decreases.
REFERENCES:
patent: 2747842 (1956-05-01), Shataloff
patent: 3612164 (1971-10-01), Miner
patent: 3933197 (1976-01-01), Zimmer et al.
patent: 5556335 (1996-09-01), Holyoake
patent: 5558274 (1996-09-01), Ben-Aissa et al.
patent: 5592059 (1997-01-01), Archer
patent: 5931227 (1999-08-01), Graves
patent: 6176777 (2001-01-01), Smith et al.
patent: 6240324 (2001-05-01), Preska et al.
patent: 6296193 (2001-10-01), West et al.
patent: 6736326 (2004-05-01), Hunka
patent: 6879881 (2005-04-01), Attridge, Jr.
patent: 2002/0109011 (2002-08-01), Fleckenstein
patent: 2006/0117769 (2006-06-01), Helt et al.
Liu, M., Claridge, D., and Turner, D., 2002, Continuous Commissioning Guidebook for Federal Energy Managers, Chapter 4, p. 28-30, Doe.
Liu, M. and Claridge, D., 1999, “Converting Dual-Duct Constant-volume Systems to Variable Volume Systems Without Retrofitting the Terminals,” ASHRAE Trans., 101(1), 66-70.
Johnson, G. A., 1984, “Retrofit of a Constant Volume Air System for Variable Speed Fan Control,” ASHRAE Transactions, 90(2B), 201-212.
Federspiel Corporation
Jiang Chen-Wen
Townsend and Townsend / and Crew LLP
LandOfFree
Method and apparatus for converting constant-volume supply... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for converting constant-volume supply..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for converting constant-volume supply... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4213876