Automatic temperature and humidity regulation – With timing element – Timer other than clock
Reexamination Certificate
1999-07-23
2001-03-06
McDermott, Corrine (Department: 3744)
Automatic temperature and humidity regulation
With timing element
Timer other than clock
C062S131000, C062S158000, C165S237000, C236S04600F, C236S051000
Reexamination Certificate
active
06196468
ABSTRACT:
This invention relates to an apparatus and process for controlling heating, air conditioning, and ventilation (HVAC) and other environmental control systems to prevent excessive and wasteful electricity consumption and premature maintenance and replacement costs.
Air conditioning and heating systems are commonly used in both residential and commercial buildings, and are commonly controlled by thermostats. However, people using these systems may leave doors or windows open for fresh air or other reasons, therefore causing the air conditioning or heating system to operate at a nearly continuous level. This continuous operation of the air conditioning or heating system creates high electricity consumption and maintenance costs because leaving the door or window open will prevent the environment from reaching the temperature setting for the thermostat. This problem is especially acute in hotels and resort vacation rental facilities in which occupants are not responsible for, and probably are unaware of, high electricity, repair and maintenance costs. These costs are therefore borne by the owner or operator of the hotel, rental facility, or other building.
A related problem arises when the air conditioner or heater in a room is turned on in the morning and throughout the entire day, even though the room has been unoccupied.
BACKGROUND ART
U.S. Pat. No. 5,476,221 to Seymour, which is incorporated herein by reference, discloses a wireless thermostatic control system including a door sensor to detect whether a room door is open and a sensor to determine whether a room is occupied, with two thermostatic controls: one for a room occupant and one for an energy saving setback mode when the room is not occupied, as detected by an infrared sensor.
U.S. Pat. No. 4,391,406 to Fried, which is incorporated herein by reference, discloses a power saving unit containing a timer and two time delays. It also assures room security by requiring the door to be properly locked before particular electric loads will be energized.
U.S. Pat. No. 4,232,819 to Bost discloses the use of a control box mounted adjacent to a door which must be activated by the room user, permitting the user to control the thermostat.
U.S. Pat. No. 4,502,290 to Suzuki, et al., discloses an air conditioner which is controlled based on illumination detected by a photo detector.
U.S. Pat. No. 4,585,162 to Evans discloses an improved automatic energy temperature control system for a room involving a second thermostat which uses less heating or cooling, with the second thermostat activated by the entry or departure of persons from the room, sensed through a switch responsive to the presence of a door chain.
U.S. Pat. No. 4,719,763 to Tietze discloses an air conditioner having a control system arranged to start operation of the fan and the cooling circuit in response to a person entering the room, and to stop operation of the fan and the cooling system in response to a person leaving the room, as determined when a hotel guest unlocks the door of the room.
U.S. Pat. No. 5,285,961 to Rodriguez, Jr. discloses a means for preventing unnecessary expense in a heating, ventilation and air condition system by using two thermostats, one with fixed limits for ambient temperatures accessible only by authorized personnel, and the other having variable limits actuated to override the fixed limits when an infrared motion sensor unit detects movement and activates the variable limit thermostat.
U.S. Pat. No. 5,318,224 to Darby, et al., discloses an energy efficient system for controlling heating and cooling equipment in which the system can be operated at various levels depending on whether motion is detected or a control signal is received from a telephone.
U.S. Pat. No. 5,538,181 to Simmons, et al., discloses an air conditioner/heater which automatically turns off the power when the room is unoccupied, with minimal installation costs and rewiring, having a digital timer.
It is therefore an object of this invention to provide an apparatus and system for deactivating an air conditioner or heater when a window or door is open or when a room is unoccupied that requires minimal installation time, especially of electricians.
It is a further object of this invention to provide such an apparatus or system that avoids unnecessary wear upon the compressor unit in an air conditioner.
It is astill further object of the present invention to provide such an apparatus and system that uses readily available components.
It is a still further object of this invention to provide such an apparatus and system in which the system controls may be located anywhere within a building.
It is a still further object of the present invention to provide an apparatus and system that separately controls the evaporator fan and the compressor.
It is a still further object of the present invention to provide such an apparatus and system in which malfunctions can be easily and quickly diagnosed to reduce the costs of repair and maintenance.
It is a still further object of the present invention to provide such an apparatus and system that can be easily and economically installed by a person of limited skill.
DISCLOSURE OF INVENTION
These and other objects are achieved by a device for controlling an HVAC (heating, ventilation and air conditioning) system, such as an air conditioner, having an evaporator fan (or, in a heating system, a blower) and a compressor (or, in a heating system, a heating element) for a room, including (1) a door/window sensor to sense whether any of the door or windows are open or closed; (2) a fan relay to activate the evaporator fan; (3) a compressor relay to activate the compressor; (4) a system timer connected to the door/window sensor to deactivate the fan relay and the compressor relay, after a shutoff delay, when the door/window sensor indicates that any of the door and windows has been opened (with the fan and compressor remaining activated if the door and windows are closed within a time less than the shutoff delay); (5) a compressor timer that delays reactivation of the compressor for a startup delay after the compressor relay has been deactivated and that overrides the system timer when the door and windows have been closed for less than that startup delay.
Preferably, the relays are normally closed to allow the compressor and fan to operate.
With this device, if the door and windows have been opened for a time period less than the shutoff delay, the system timer prevents deactivation of the fan relay and the compressor relay. Thus, for example, if the shutoff delay is set for 15 seconds, opening and closing a door within 15 seconds (such as when entering and leaving the room) will not deactivate the fan or compressor.
If the door and windows have been opened for a period exceeding the shutoff delay and the startup delay, then the fan relay and compressor relay will be reactivated immediately when all of the door and windows are closed. Thus, if the shutoff delay is set for 15 seconds and the startup delay is set for five minutes, if the door and windows have been opened for a period longer than five minutes and 15 seconds, the fan and compressor will be reactivated immediately after the door and windows are closed.
However, if the door and windows are opened for longer than the shutoff delay (so that the fan and compressor have been turned off), but less than the startup delay (for example, five minutes), the compressor timer will prevent reactivation of the compressor until the expiration of the startup delay, thus preventing the compressor from being turned on and off more frequently than the startup delay allows. This prevents wear and tear on the compressor and reduces the need for maintenance that would be caused if the compressor were turned on and off more frequently than allowed by the startup delay.
Preferably, the shutoff delay can be preselected by setting the system timer, and the delay is preferably approximately 15 seconds, but can be in a range between 5 seconds and 1 minute. Preferably the startup delay can be preselected by setting th
Hsia Martin E.
McDermott Corrine
Norman Marc
LandOfFree
Air conditioning and heating environmental control sensing... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Air conditioning and heating environmental control sensing..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Air conditioning and heating environmental control sensing... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2462580