Abstract:
A device that automatically disables an air-moving device if smoke is detected in a building by a smoke detector is disclosed in which a smoke detector and a control circuit that use signals generated by the smoke detector disrupts the current flowing through either the control or power wiring for the air-moving device. The device is hard wired or wireless and eliminates the distribution of smoke throughout the building by an air-moving device thus preventing unnecessary property damage, smoke inhalation and smoke-filled escape routes, saving money and lives.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of priority of U.S. Provisional Application No. 60/274,625, titled “The Automatic Disabling of a Forced Air Furnace or Other Air-Moving Device When the Presence of Smoke is Detected” and filed Mar. 12, 2001, incorporated by reference herein as if set forth in full. 
     
    
     
       BACKGROUND OF INVENTION  
         [0002]    This invention relates to the automatic control of an air-moving device if smoke is detected in a building, utilizing the combination of a smoke detection device and a control circuit.  
           [0003]    In a typical fire in a building, a significant amount of property damage and human injury, including most fire-related fatalities, are caused by smoke. When a fire begins, the building&#39;s forced-air furnace or other air-moving device circulates the smoke and hot air that result throughout the rest of the structure. This is especially true when cold air returns and/or furnace air intakes are located near the ceiling where smoke tends to collect. When smoke is circulated throughout the structure, preventable smoke damage occurs to property. Circulating smoke creates difficulties for rescue personnel to pinpoint the location of the fire. Circulating smoke may also prevent people in the building from being able to breathe, see clearly to escape and survive.  
           [0004]    The present invention automatically disables air-moving devices when smoke is detected within a structure thereby limiting the amount of smoke that may be circulated through the rest of the building.  
           [0005]    Several existing patents use smoke detectors to turn off devices that actually cause or add fuel to a fire, but no system currently exists to prevent the circulation of smoke throughout a building in response to any smoke-related event. U.S. Pat. No. 5,670,074 to Kass provides an internal apparatus to shut off a furnace if the furnace catches fire, leaks fuel, or exhausts gases. Similarly, U.S. Pat. No. 4,659,909 to Knutson provides a system for shutting off an electric range when smoke is detected at the appliance itself. However, neither of these systems takes into account smoke from any other sources or locations throughout a building. Neither of these systems is designed to prevent the circulation of smoke throughout the building by any potential air-moving device.  
           [0006]    U.S. Pat. No. 6,130,412 to Sizemore details a system that monitors its own remote sensors and turns off/on household appliances to prevent further fuel from being added to an existing fire. Sizemore does not address the problem of an air-moving device such as used with a forced air furnace or other HVAC cooling or heating device when smoke is present.  
           [0007]    The present invention is designed to stop the unnecessary circulation of smoke by any air-moving apparatus during a fire. An advantage of the present invention is that the invention uses existing smoke detectors and smoke detection technology, rather than its own sensor array. Individuals around the world could use the proposed invention to retrofit or replace their existing smoke detectors cheaply and easily, preventing a potentially devastating circulation of smoke.  
           [0008]    The principal object of the invention presented is to eliminate the possibility of smoke being distributed throughout a building by the operation of a forced air furnace or other air-moving or powered ventilation device such as air conditioners, evaporative coolers, attic fans, ceiling fans, airtight fireplaces, etc. The present invention works by automatically disabling the air-moving apparatus when smoke is detected within the building. This invention builds upon existing smoke detection capabilities to create a new device and method that may potentially save lives.  
           [0009]    A smoke detector consists of a circuit that detects the presence of smoke and sends a signal to an alarm such as a siren, bell, whistle, or horn (herein a siren), which provides an audible notification that smoke is present. In the present invention the smoke detector also sends a signal (either the same signal sent to the siren or a separately generated signal) to a control circuit, which automatically disrupts the operation of an air-moving apparatus such as a forced-air furnace.  
           [0010]    In the preferred embodiment, the current flowing from the air-moving apparatus to its control mechanism (i.e. thermostat or timer) will be disrupted automatically by the control circuit, preventing the apparatus from being activated while smoke is present. In situations where a control mechanism is not available, the current used to power the air-moving apparatus is disrupted directly by the control circuit. The control circuit consists of a relay that uses the signal supplied by the smoke detector to open or close the switches through which the power to the control mechanism or air-moving apparatus is routed.  
           [0011]    The present invention includes the advantage of resumption of power to the control mechanism or air-moving apparatus when the smoke sensor no longer detects smoke in the structure. In cases where the fire is quickly contained, this feature allows automatic reactivation of the air-moving apparatus.  
           [0012]    Three configurations of the invention with variations are described (one single smoke detector/control circuit unit and multiple smoke detector/control circuit units; both wireless and electrically connected): 1. A single smoke detector either AC or DC powered with one control circuit system. Power to the air-moving apparatus (or control unit) is disabled when smoke reaches the area containing the smoke detector. Systems, operating independently, may be placed throughout the building.  
           [0013]    2. Stand-alone multiple smoke detectors, each with one control circuit system. The control unit (such as the furnace thermostat) wiring or power wiring for the air-moving apparatus is routed through the control circuit of each smoke detector. The air-moving apparatus is disabled when smoke reaches any area containing a smoke detector.  
           [0014]    3. Interconnected multiple smoke detectors with one control circuit system. When one smoke detector in the system detects the presence of smoke, a signal is sent to all other smoke detectors (via a wire or wirelessly) closing the switch in the other smoke detectors and activating the siren. The control unit (such as the furnace thermostat) wiring or the air-moving apparatus” power wiring is routed through a single control circuit attached to one of the smoke detectors in the system or located remotely.  
           [0015]    The use of multiple smoke detector systems (in configuration) is more likely to ensure that any unnecessary circulation of smoke is prevented. The more smoke detectors that are used, the more likely smoke will be detected prior to reaching any air-moving apparatuses and channels within the building. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0016]    [0016]FIG. 1 is a schematic drawing of a device for automatically controlling an air-moving apparatus with a smoke detector.  
         [0017]    [0017]FIG. 2 is a schematic drawing of a device for automatically controlling an air-moving apparatus with multiple smoke detectors and control circuits.  
         [0018]    [0018]FIG. 3 is a schematic drawing of a device for automatically controlling an air-moving apparatus with multiple interactive smoke detectors.  
         [0019]    [0019]FIG. 4 is a schematic drawing of a wireless version of a device for automatically controlling an air-moving apparatus with smoke detectors.  
         [0020]    [0020]FIG. 5 is a schematic drawing of a device for automatically controlling an air-moving apparatus with multiple interactive smoke detectors using a wireless configuration. 
     
    
     DETAILED DESCRIPTION  
       [0021]    Referring to FIG. 1, the preferred embodiment employs a smoke detector  1  and a control circuit  6 . When a smoke sensor  2 , detects smoke, a switch  3  interconnected the smoke sensor  2  and a siren  4 , is activated. Connected to the switch  3  are control wires  5 , which are further connected to a relay  7  of a control circuit  6 . In the open position, no current flows through the switch  3 . When the switch  3  is closed, a signal is sent through the control wires  5  to the normally closed relay  7  connected to the control circuit  6 . The relay  7  opens and disrupts the current flowing through the wires  8 ,  8   a  to the air-moving apparatus  1   2  control unit  11 . The system may also be directly connected to the air-moving apparatus  12  as shown in FIG. 1A. The opened relay  7  disrupts the circuit and prevents the air-moving apparatus  12  from operating as long as smoke is detected by the smoke sensor  2 . If the smoke sensor  2  no longer detects smoke, the switch  3  returns to the open position, closing the relay  7  and restoring the circuit to the air-moving apparatus  1   2  or the control unit  11 .  
         [0022]    [0022]FIG. 2 shows multiple smoke detectors  1 - 1  n each with a control circuit  6 - 6   n.    
         [0023]    Each control circuit  6 - 6   n  is independently connected to a smoke detector  1 - 1   n  and additionally connected through wires  8 ,  8   a  traveling to the air-moving apparatus  12  in series. If any one smoke detector  1 - 1   n  is energized by a smoke sensor  2 , a switch  3  sends current through wires  5  to open the relay  7  of the control circuit  6 - 6   n  to disrupt the current flowing through the wire  8  and deactivate the control unit  11  of the air-moving apparatus  12 .  
         [0024]    [0024]FIG. 3 shows a wired interactive system. In this system, any smoke sensor  2  detecting smoke closes the switch  3  of that smoke detector  1 . The closed switch  3  sends a signal via a wire  5   b  to the relay  7  and via a wire  5   c  to a second smoke detector  1   n . The signal closes the second smoke detector  1   n  switch  3   n  to activate a second siren  4   n . The second smoke detector  1   n  in turn sends a second signal via a wire  5   b - 5   bn  to the relay  7  and via a wire  5   c - 5   cn  to an additional smoke detector  1   n  and the process repeats. The system shown in FIG. 3 is advantageous if a fire has destroyed the wiring of a smoke detector  1  leading to the control circuit  6 .  
         [0025]    The control circuit  6  may also be remote from the smoke detector  1 . As shown in FIG. 4, a control circuit  6  placed near one or more than one smoke detector  1 - 1   n  includes a microphone  9   a  connected to the relay  7  of the control circuit  6 . When the siren  4  is activated, the microphone  9   a  hears the audible signal. The microphone  9   a  sends an output to the relay  7 . The output opens the relay  7 , disrupting the current flowing through the air-moving apparatus  12  control unit  11  or power wiring  8 . When the smoke sensor  2  no longer detects smoke, the switch  3  opens, deactivating the siren  4 , and the microphone  9   a  discontinues output to the relay  7 . The relay  7  reverts to the closed position restoring the circuit to the air-moving apparatus  12 .  
         [0026]    [0026]FIG. 5 depicts interactive smoke detectors in a wireless system. When smoke is detected by any smoke sensor  2 - 2   n  of one or more than one smoke detector  1 - 1  n, the switch  3 - 3   n  closes and sends a signal to an input/output component  10 - 10   n  interconnected to the switch  3 - 3   n  and the sensor  2 - 2   n . The energized input/output component  10 - 10   n  sends a signal to a sensor  9  connected to the control circuit  6  and to a second input/output component  10 - 10   n  interconnected to one or more than one smoke detector  1 - 1   n . The signal energizes the sensor  9  of the control circuit  6  and the sensor  9  sends an output to the relay  7  to open the relay  7 . The opened relay  7  disrupts the current flowing through the air-moving apparatus  12  or control unit  11 . The signal to the second input/output component  10 - 10   n  activates the switch  3   n  of that smoke detector  1 - 1   n , which activates the siren  4   n . The second input/output component  10 - 10   n  additionally sends a signal to the sensor  9  as well as to additional input/output components  10 - 10   n  and the process repeats.  
         [0027]    Should the smoke sensor  2 - 2   n  no longer detect smoke, the input/output component  10 - 10   n  discontinues the signal to the sensor  9  and to the second input/output component  10 - 10   n . The sensor  9  discontinues sending output to the relay  7 , which closes the relay  7 . The closed relay  7  restores the current flowing through the air-moving apparatus  12  or control unit  11 .  
         [0028]    The preferred embodiments herein disclosed are not intended to be exhaustive or to unnecessarily limit the scope of the invention. The preferred embodiments were chosen and described in order to explain the principles of the present invention so that others skilled in the art may practice the invention. Having shown and described preferred embodiments of the present invention, those skilled in the art will realize that many variations and modifications may be made to affect the described invention. Many of those variations and modifications will provide the same result and fall within the spirit of the claimed invention. It is the intention, therefore, to limit the invention only as indicated by the scope of the claims.