Heat exchange – With valve or movable deflector for heat exchange fluid flow – With by-pass of heat exchanger or heat exchanger section
Patent
1979-04-30
1981-03-24
Yuen, Henry C.
Heat exchange
With valve or movable deflector for heat exchange fluid flow
With by-pass of heat exchanger or heat exchanger section
165 15, 165 31, 236 78D, B64D 1300
Patent
active
042573181
ABSTRACT:
A pressure control system for an air distribution system which includes a supply blower (10), a distribution duct network (20) and a plurality of air outlets (22a, 22b), includes a plurality of pressure sensors (25a, 25n) positioned at various points in the air ducts to measure pressure therein. Controls are provided for selecting the lowest of the sensed pressures (42) and the low pressure signal becomes one input to a variable dead band controller (44). Another input is an adjustment (45) for commanding the desired system pressure. The controller compares the pressure to a dead band threshold established about the set point and delivers appropriate signals to an actuator (31) which operates through a linkage (32) to control the inlet vortex vanes (33) and hence the air flow of the supply blower. A wide dead band is used to avoid hunting of the system, but when a response is required a narrow dead band is used to ensure that the system drives to the set point. Controls are provided (47) to periodically reset the controller to its narrow dead band position to prevent drift of the system. For systems also including a return blower (11) an additional controller (54) is provided to operate its actuator (35) to control its inlet vanes (37). Controls are provided (31b, 35b) for developing feedback signals indicative of air flow in the supply and return blowers, and these signals are applied to calibration circuits (52, 56) to the controller (54). The calibration circuits are specially designed to provide independent adjustment of maximum and minimum air flow tracking between the supply and return blowers.
REFERENCES:
patent: 2112520 (1938-03-01), Crawford
patent: 2282210 (1942-05-01), Plum
patent: 3591077 (1971-07-01), Alton
patent: 4011735 (1977-03-01), Martz
patent: 4044947 (1977-08-01), Spethmann
Bennett Henry
McQuay-Perfex Inc.
Yuen Henry C.
LandOfFree
Variable dead band pressure control system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Variable dead band pressure control system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Variable dead band pressure control system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2404987